d(-)-α-aminobenzylpenicillin

d(-)-α-aminobenzylpenicillin (a-me-no-ben′zil-pen-i-sil′in)

SYN: ampicillin.

δ-aminobutyric acid amino transferase
δ-aminobutyric acid amino transferase

An enzyme catalyzing the reversible transfer of an amino group from δ-aminobutyric acid to 2-oxoglutarate, thus forming a l-glutamic acid and succinate semialdehyde. An important step in the catabolism of δ-aminobutyric acid.

δ-aminolevulinate dehydratase
δ-aminolevulinate dehydratase (a-me′no-lev-u-lin′at)

SYN: porphobilinogen synthase.

δ-aminolevulinic acid
δ-aminolevulinic acid (ALA) (a-me′no-lev-u-lin′ik)

An acid formed by δ-aminolevulinate synthase from glycine and succinyl-coenzyme A; a precursor of porphobilinogen, hence an important intermediate in the biosynthesis of heme. ALA levels are elevated in cases of lead poisoning.
δ-aminolevulinic acid synthase an enzyme that catalyzes the reaction of succinyl-CoA with glycine to form δ-aminolevulinic acid, coenzyme A, and CO₂. The committed step in porphyrin biosynthesis.

d-amphetamine phosphate
d-amphetamine phosphate

SYN: dextroamphetamine phosphate.

d-amphetamine sulfate
d-amphetamine sulfate

SYN: dextroamphetamine sulfate.

Δ check
Δ check

SYN: delta check.

Δ
Δ, δ

1. Fourth letter of the Greek alphabet, delta. 2. In chemistry, denotes a double bond, usually with a superscript to indicate position in a chain (Δ⁵); application of heat in a reaction (A B); absence of heat treatment (&&slash;); distance between two atoms in a molecule; or position of a substituent located on the fourth atom from the carboxyl or other primary functional group (δ); change (Δ); thickness (δ); chemical shift in NMR (δ).

D
D

1. Symbol for the vitamin D potency of cod liver oil, multiples of which (5D, 100D, etc.) are used to designate the vitamin D potency of irradiated ergosterol (viosterol) or other substances; for deuterium; for dihydrouridine in nucleic acids; for diffusing capacity; for aspartic acid; dihydrouridine; diffusion coefficient (in italics). 2. In optics, abbreviation for diopter; for dexter (right). 3. In electrodiagnosis, abbreviation for duration, the current flowing and the circuit being closed. 4. In dental formulas, abbreviation for deciduous (2) . 5. As a subscript, refers to dead space. See physiologic dead space. 6. D line in Na emission spectra.

2,4-D
2,4-D

Abbreviation for (2,4-dichlorophenoxy) acetic acid.

d
d

Symbol for deci-; abbreviation for dexter [L], right; diameter; day.

d- d-

Prefix indicating a chemical compound to be dextrorotatory; should be avoided when (+) or (−) could be used. Cf.:l-.

d- d-

Prefix indicating that a chemical compound is sterically related to d-glyceraldehyde, the basis of stereochemical nomenclature. Cf.:l-.

-d -d

Suffix indicating the presence of deuterium in a compound in concentrations above normal, thus labeling the compound; subscripts (d₂, d₃, etc.) indicate the number of such atoms so fortified.

DA
DA

Abbreviation for developmental age (2) .

Da
Da

Symbol for dalton.

dA
dA, dAdo

Abbreviation for deoxyadenosine.

da
da

Symbol for deca-.

Daae
Daae

Anders, Norwegian physician, 1838–1910. See D. disease.

DAB
DAB

Abbreviation for 3′3-diaminobenzidine HCl; in the immunoperoxidase technique, used to produce a colored complex at the site of peroxidase activity.

dacarbazine
dacarbazine (DTIC) (da-kar′ba-zen)

An antineoplastic agent used in the treatment of malignant melanoma and sarcoma.

dacry- dacry-

See dacryo-.

dacryadenitis
dacryadenitis (dak′re-ad-e-ni′tis)

SYN: dacryoadenitis.

dacryo- dacryo-, dacry-

Tears; lacrimal sac or duct. [G. dakryon, tear]

dacryoadenitis
dacryoadenitis (dak-re-o-ad-e-ni′tis)

Inflammation of the lacrimal gland. SYN: dacryadenitis. [dacryo- + G. aden, gland, + -itis, inflammation]

dacryoblennorrhea
dacryoblennorrhea (dak-re-o-blen-o-re′a)

A chronic discharge of mucus from a lacrimal sac. [dacryo- + G. blenna, mucus, + rhoia, flow]

dacryocele
dacryocele (dak′re-o-sel)

SYN: dacryocystocele.

dacryocyst
dacryocyst (dak′re-o-sist)

SYN: lacrimal sac. [dacryo- + G. kystis, sac]

dacryocystalgia
dacryocystalgia (dak′re-o-sis-tal′je-a)

Pain in the lacrimal sac. [dacryocyst + G. algos, pain]

dacryocystectomy
dacryocystectomy (dak′re-o-sis-tek′to-me)

Surgical removal of the lacrimal sac. [dacryocyst + G. ektome, excision]

dacryocystitis
dacryocystitis (dak′re-o-sis-ti′tis)

Inflammation of the lacrimal sac. [dacryocyst + G. -itis, inflammation]

dacryocystocele
dacryocystocele (dak′re-o-sis′to-sel)

Enlargement of the lacrimal sac with fluid. SYN: dacryocele. [dacryocyst + G. kele, hernia]

dacryocystogram
dacryocystogram (dak′re-o-sis′to-gram)

A radiograph of the lacrimal apparatus obtained after injection of contrast material for the purpose of determining the presence of and localizing a site of obstruction; this procedure has been largely replaced by the CT and MRI. [dacryocyst + G. gramma, a writing]

dacryocystorhinostomy
dacryocystorhinostomy (dak′re-o-sis′to-ri-nos′to-me)

An operation providing an anastomosis between the lacrimal sac and the nasal mucosa through an opening in the lacrimal bone. [dacryocyst + G. rhis (rhin-), nose, + stoma, mouth]

dacryocystotomy
dacryocystotomy (dak′re-o-sis-tot′o-me)

Incision of the lacrimal sac. [dacryocyst + G. tome, incision]

dacryohemorrhea
dacryohemorrhea (dak′re-o-hem-o-re′a)

Bloody tears. [dacryo- + G. haima, blood, + rhoia, flow]

dacryolith
dacryolith (dak′re-o-lith)

A concretion in the lacrimal apparatus. SYN: lacrimal calculus, ophthalmolith, tear stone. [dacryo- + G. lithos, stone]
Desmarres dacryoliths SYN: Nocardia dacryoliths.
Nocardia dacryoliths white pseudoconcretions, composed of masses of Nocardia species found in the lacrimal canaliculi. SYN: Desmarres dacryoliths.

dacryolithiasis
dacryolithiasis (dak′re-o-li-thi′a-sis)

The formation and presence of dacryoliths.

dacryon
dacryon (dak′re-on)

The point of junction of the frontomaxillary and lacrimomaxillary sutures on the medial wall of the orbit.See figure under craniometric points, under point. [G. a tear]

dacryops
dacryops (dak′re-ops)

1. Excess of tears in the eye. 2. A cyst of a duct of the lacrimal gland. [dacryo- + G. ops, eye]

dacryopyorrhea
dacryopyorrhea (dak′re-o-pi-o-re′a)

The discharge of tears containing leukocytes. [dacryo- + G. pyon, pus, + rhoia, flow]

dacryorrhea
dacryorrhea (dak′re-o-re′a)

An excessive secretion of tears. [dacryo- + G. rhoia, flow]

dacryostenosis
dacryostenosis (dak′re-o-ste-no′sis)

Stricture of the lacrimal duct. [dacryo- + G. stenosis, narrowing]

dactinomycin
dactinomycin (dak′ti-no-mi′sin)

Produced by several species of Streptomyces ( e.g., S. parvulus); an antineoplastic antibiotic used especially for Ewing sarcoma, rhabdomyosarcoma, and Wilms tumor in children and for trophoblastic disease in women. SEE ALSO: actinomycin. SYN: actinomycin D.

dactyl
dactyl (dak′til)

SYN: digit. [G. daktylos]

dactyl- dactyl-

See dactylo-.

dactylalgia
dactylalgia (dak-ti-lal′je-a)

Pain in the fingers. SYN: dactylodynia. [dactyl- + G. algos, pain]

Dactylaria
Dactylaria (dak-ti-la′re-a)

A genus of dematiaceous soil-dwelling fungi. D. gallopava is a causative agent of phaeohyphomycosis in chickens and turkeys. [G. daktylos, finger]

dactylitis
dactylitis (dak-ti-li′tis)

Inflammation of one or more fingers.
blistering distal d. infection of the volar fat pad of the distal phalanx of the finger by group A β-hemolytic streptococci.
sickle cell d. SYN: hand-and-foot syndrome.

dactylo- dactylo-, dactyl-

The fingers and (less often) toes. See entries under digit. [G. daktylos, finger]

dactylocampsis
dactylocampsis (dak′ti-lo-kamp′sis)

Permanent flexion of the fingers. [dactylo- + G. kampsis, bending]

dactylocampsodynia
dactylocampsodynia (dak′ti-lo-kamp′so-din′e-a)

Painful contraction of one or more fingers. [dactylo- + G. kampsis, a bending, + odyne, pain]

dactylodynia
dactylodynia (dak′ti-lo-din′e-a)

SYN: dactylalgia.

dactylogryposis
dactylogryposis (dak′ti-lo-gri-po′sis)

Contraction of the fingers. [dactylo- + G. gryposis, a crooking]

dactylology
dactylology (dak′ti-lol′o-je)

The use of the finger alphabet in communicating. SYN: cheirology, chirology. [dactylo- + G. logos, word]

dactylomegaly
dactylomegaly (dak′til-o-meg′a-le)

SYN: megadactyly. [dactylo- + G. megas, large]

dactyloscopy
dactyloscopy (dak-ti-los′ko-pe)

An examination of the markings in prints made from the fingertips; employed as a method of personal identification. See Galton system of classification of fingerprints, under fingerprint. [dactylo- + G. skopeo, to examine]

dactylospasm
dactylospasm (dak′ti-lo-spazm)

Spasmodic contraction of the fingers or toes.

dactylus
dactylus, pl .dactyli (dak′ti-lus, -li)

SYN: digit. [G. daktylos]

dacuronium
dacuronium (dak-u-ro′ne-um)

A nondepolarizing steroid neuromuscular blocking agent with more rapid onset and shorter duration of action than pancuronium.

Da Fano
Da Fano

Corrado D., Italian-American anatomist, 1879–1927. See D. stain.

DAG
DAG

Abbreviation for diacylglycerol.

dagga
dagga (dag′a)

Leaves of Leonotis leonurus, a plant found in South Africa, where it is smoked like tobacco with mild sedative effect; a term mistakenly applied to Indian hemp, Cannabis sativa. [aborigines' term]

Dagnini
Dagnini

Giuseppe, Italian physician, 1866–1928. See Aschner-D. reflex.

DAH
DAH

Abbreviation for disordered action of heart.

dahlia
dahlia (dal′yah)

A violet dye, methyl-triethyl-amino-triphenyl-carbinol chloride. Also called Hoffman violet.

dahlin
dahlin

SYN: inulin. [fr. dahlia, after A. Dahl, Swedish botanist, 1751–1789]

dahllite
dahllite (dah′lit)

A naturally occurring calcium phosphate, similar in structure to the mineral portions of bones and teeth. SYN: podolite.

daisy
daisy (da′ze)

Colloquial term descriptive of the segmented forms (merozoites) of the mature schizont of Plasmodium malariae.

Dakin
Dakin

Henry, U.S. chemist, 1880–1952. See D. fluid, D. solution, D.-Carrel treatment.

Dale
Dale

Sir Henry Hallett, English physiologist and Nobel laureate, 1875–1968. See D. reaction, D.-Feldberg law, Schultz-D. reaction.

Dalen
Dalen

Johan A., Swedish ophthalmologist, 1866–1940. See D.-Fuchs nodules, under nodule.

Dalgarno
Dalgarno

Lynn, contemporary Australian molecular biologist.

Dalrymple
Dalrymple

John, English oculist, 1803–1852. See D. sign.

Dalton
Dalton

John, English chemist, mathematician, and natural philosopher, 1766–1844. See D. law, D.-Henry law, daltonian, daltonism.

dalton
dalton (Da) (dawl′ton)

Term unofficially used to indicate a unit of mass equal to ¹/₁₂ the mass of a carbon-12 atom, 1.0000 in the atomic mass scale; numerically, but not dimensionally, equal to molecular or particle weight (atomic mass units). [J D.]

daltonian
daltonian (dawl-to′ne-an)

1. Attributed to or described by John Dalton. 2. Pertaining to daltonism.

daltonism
daltonism (dawl′ton-izm)

A color vision deficiency, especially deuteranomaly or deuteranopia. [J. Dalton]

DALYs
DALYs

Abbreviation for disability-adjusted life years, under year.

DAM
DAM

Abbreviation for diacetylmonoxime.

Dam
Dam

C.P. Henrik, Danish biochemist and Nobel laureate, 1895–1976. See D. unit.

dam
dam

1. Any barrier to the flow of fluid. 2. In surgery and dentistry, a sheet of thin rubber arranged so as to shut off the part operated upon from the access of fluid. [A.S. fordemman, to stop up]
post d. SYN: posterior palatal seal.
rubber d. 1. in surgery, thin strips of rubber used as a surgical drain or barrier; 2. a thin sheet of rubber with holes that is placed over teeth to isolate them from the oral cavity.

damage
damage

diffuse alveolar d. SYN: adult respiratory distress syndrome.

Damalinia
Damalinia (dam-a-lin′e-a)

A genus of biting lice containing a number of species found on domestic and wild animals; they are all highly host-specific, one species being confined to each species of mammal. SEE ALSO: Bovicola, Trichodectes.

dammar
dammar

A resin resembling copal, obtained from various species of Shorea (family Dipterocarpaceae) in the East Indies; used, dissolved in chloroform, for mounting microscopic specimens. [Hind. damar, resin]

dam methylase
dam methylase

An enzyme responsible for the methylation of adenine residues in specific sequences. SYN: deoxyadenosine methylase.

dAMP
dAMP

Abbreviation for deoxyadenylic acid.

damp
damp

1. Humid; moist. 2. Atmospheric moisture. 3. Foul air in a mine; air charged with carbon oxides (black or choke d.) or with various explosive hydrocarbon vapors (firedamp).

damping
damping

Bringing a mechanism to rest with minimal oscillation; e.g., in echocardiography, electrical or mechanical loading to reduce duration of echo, transmitter pulse, and transmitter complex. [M.E. damp, poisonous vapor]

Damus-Kaye-Stancel procedure
Damus-Kaye-Stancel procedure

See under procedure.

Dana
Dana

Charles L., U.S. neurologist, 1852–1935. See D. operation, Putnam-D. syndrome.

danazol
danazol (da′na-zol)

An anterior pituitary suppressant used in the treatment of endometriosis, fibrocystic breast disease, and angioedema.

Dance
Dance

Jean B.H., French physician, 1797–1832. See D. sign.

dance
dance (dans)

Involuntary movements related to brain damage.
hilar d. vigorous pulmonary arterial pulsations due to increased blood flow, often seen fluoroscopically in patients with congenital left-to-right shunts, especially atrial septal defects.
Saint Anthony d., Saint Vitus d., Saint John d. obsolete eponyms for Sydenham chorea.

dander
dander

1. A fine scaling of the skin and scalp. SEE ALSO: dandruff. 2. A normal effluvium of animal hair or coat capable of causing allergic responses in atopic persons.

dandruff
dandruff (dan′druf)

The presence, in varying amounts, of white or gray scales in the hair of the scalp, due to excessive or normal branny exfoliation of the epidermis. SEE ALSO: seborrheic dermatitis. SYN: pityriasis capitis, scurf, seborrhea sicca (2) .

Dandy
Dandy

Walter E., U.S. neurosurgeon, 1886–1946. See D. operation, D.-Walker syndrome.

Dane
Dane

D.S., 20th century British virologist. See D. particles, under particle.

Dane stain
Dane stain

See under stain.

Danforth
Danforth

William Clark, U.S. obstetrician-gynecologist, 1878–1949. See D. sign.

Danielssen
Danielssen

Daniel C., Norwegian physician, 1815–1894. See D. disease, D.-Boeck disease.

Danlos
Danlos

Henri A., French dermatologist, 1844–1912. See Ehlers-D. syndrome.

DANS
DANS

Abbreviation for 1-dimethylaminonaphthalene-5-sulfonic acid; a green fluorescing compound used in immunohistochemistry to detect antigens.

dansyl
dansyl (Dns, DNS) (dan′sil)

The 5-dimethylaminonaphthalene-1-sulfonyl radical;a blocking agent for NH₂ groups, used in peptide synthesis.

danthron
danthron

An anthraquinone laxative. SYN: chrysazine.

dantrolene sodium
dantrolene sodium (dan′tro-len)

A synthetic skeletal muscle relaxant that acts directly on muscle by uncoupling electrical from mechanical events; also, the specific agent for prevention and treatment of malignant hyperthermia.

Danysz
Danysz

Jan, Polish pathologist in France, 1860–1928. See D. phenomenon.

DAPI
DAPI

Abbreviation for 4′6-diamidino-2-phenylindole&chmpnt;2HCl, a fluorescent probe for DNA. See D. stain.

dapsone
dapsone (dap′son)

An antibiotic used in the treatment of leprosy and certain cutaneous diseases such as dermatitis herpetiformis, is active against the tubercle bacillus, is used in the treatment of bovine coccidiosis and streptococcal mastitis, and is used as a second-line agent in Pneumocystis carinii pneumonia, a disease common in AIDS patients.

d'Arcet
d'Arcet

Jean, French chemist, 1725–1801. See d'Arcet metal.

Darier
Darier

Jean F., French dermatologist, 1856–1938. See D. disease, D. sign.

Darkschewitsch
Darkschewitsch, Darkshevich

Liverij O., Russian neurologist, 1858–1925. See nucleus of D..

Darling
Darling

Samuel Taylor, U.S. physician in Panama, 1872–1925. See D. disease.

Darrow red
Darrow red

A basic oxazin dye used as a substitute for cresyl violet acetate in the staining of Nissl substance. [Mary A. Darrow, U.S. stain technologist, 1894–1973]

d'Arsonval
d'Arsonval

Jacques Arsène, French biophysicist, 1851–1940. See d'Arsonval current, d'Arsonval galvanometer.

dartoic
dartoic, dartoid (dar-to′ik, dar′toyd)

Resembling tunica dartos in its slow involuntary contractions. [G. dartos, flayed]

dartos
dartos (dar′tos)

See d. fascia. [G. skinned or flayed, fr. dero, to skin]
d. muliebris a very thin layer of smooth muscle in the integument of the labia majora; less well-developed than the tunica d. of the scrotum.

Darwin
Darwin

Charles R., English biologist and evolutionist, 1809–1882. See darwinian ear, darwinian evolution, darwinian reflex, darwinian theory, darwinian tubercle.

darwinian
darwinian (dar-win′e-an)

Relating to or ascribed to Darwin.

Dasyprocta
Dasyprocta (das′e-prok′ta)

A genus of rodents of the guinea pig family, a reservoir host of Trypanosoma cruzi. SYN: agouti. [G. dasyproktos, having hairy buttocks]

data
data

Multiple facts (usually but not necessarily empirical) used as a basis for inference, testing, models, etc. The word is plural and takes a plural verb.

data processing
data processing

Conversion of crude information into usable or storable form; statistical analysis of data by a computer program.

datum
datum (da′tum)

An individual piece of information used in a scholarly field. [L., given, fr. do, pp. d., to give]

Datura
Datura (da-too′ra)

A genus of solanaceous plants. Several species (D. arborea, D. fastuosa, D. ferox, and D. sanguinea) are used in Brazil, India, and Peru to produce unconsciousness. The seeds contain hyoscine (scopolamine), an alkaloid with an anticholinergic action similar to that of atropine. [Hind.]
D. metel D. fastuosa L. var. alba; a species that contains scopolamine as its chief alkaloid and traces of hyoscyamine and atropine.
D. stramonium a species that is the main source of stramonium. SYN: Jamestown weed, jimson weed, stink weed, thorn apple.

daturine
daturine (da-too′rin, -ren)

SYN: hyoscyamine.

Daubenton
Daubenton, D'Aubenton

Louis J.M., French physician, 1716–1799. See D. angle, D. line, D. plane.

daughter
daughter (daw′ter)

In nuclear medicine, an isotope that is the disintegration product of a radionuclide. See d. isotope, radionuclide generator. [O.E. dohtor]
DES (diethylstilbestrol) d. the d. of a woman who received diethylstilbestrol during pregnancy; DES daughters are at risk of deformity, adenosis, and other epithelial changes of the vagina and cervix, including clear cell adenocarcinoma.

daunomycin
daunomycin (daw-no-mi′sin)

SYN: daunorubicin.

daunorubicin
daunorubicin (daw-no-roo′bi-sin)

An antibiotic of the rhodomycin group, obtained from Streptomyces peucetius; used in the treatment of acute leukemia; also used in cytogenetics to produce Q-type chromosome bands. SYN: daunomycin.

Davidoff
Davidoff

M. von, German histologist, &dag;1904. See D. cells, under cell.

Davidson
Davidson

Edward C., U.S. surgeon, 1894–1933. See D. syringe.

Daviel
Daviel

Jacques, French oculist, 1693–1762. See D. operation, D. spoon.

Davies
Davies

J.N.P., U.S. pathologist, *1915. See D. disease.

Davis
Davis

John Staige, U.S. surgeon, 1872–1946. See D. graft, Crowe-D. mouth gag.

Davis
Davis

Hallowell, U.S. physiologist, 1896–1992. See D. battery model of transduction.

Davis
Davis

David M., U.S. urologist, *1886.

Davis interlocking sound
Davis interlocking sound

See under sound.

Dawson
Dawson

James R., U.S. pathologist, *1908. See D. encephalitis.

Day
Day

Richard H., U.S. physician, 1813–1892. See D. test.

Day
Day

Richard L., U.S. pediatrician, *1905. See Riley-D. syndrome.

dazzling
dazzling

The consequence of illumination too intense for adaptation by the eye; in contrast to glare, d. is alleviated by appropriate tinted glasses.

dB
dB, db

Abbreviation for decibel.

DBP
DBP

Abbreviation for vitamin D–binding protein.

DC
DC

Abbreviation for direct current.

D & C
D & C

Abbreviation for dilation and curettage.

D.C.
D.C.

Abbreviation for Doctor of Chiropractic.

dCMP
dCMP

Abbreviation for deoxycytidylic acid.

DDA
DDA

Abbreviation for dideoxyadenosine.

DDI
DDI

Abbreviation for dideoxyinosine.

d-dimer
d-dimer (di′mer)

A covalently cross-linked degradation product released from the cross-linked fibrin polymer during plasmin-mediated fibrinolysis; laboratory measurements of this product made using latex bead or ELISA assays can be used to identify the presence of fibrinolysis.

D.D.S.
D.D.S.

Abbreviation for Doctor of Dental Surgery.

DDT
DDT

Abbreviation for dichlorodiphenyltrichloroethane.

D & E
D & E

Abbreviation for dilation and evacuation. 2. Abbreviation for dilation and extraction

de- de-

1. Away from, cessation, without; sometimes has an intensive force. 2. For names with this prefix not found here, see under the principal part of the name. [L. de, from, away]

deacidification
deacidification (de-a-sid′i-fi-ka′shun)

The removal or neutralization of acid.

deactivation
deactivation (de-ak-ti-va′shun)

The process of rendering or of becoming inactive.

deacylase
deacylase (de-as′il-as)

1. A member of the subclass of hydrolases (EC class 3), especially of that subclass of esterases, lipases, lactonases, and hydrolases (EC subclass 3.1). 2. Any enzyme catalyzing the hydrolytic cleavage of an acyl group (R&cbond;CO&cbond;) in an ester linkage; also includes enzymes cleaving amide linkages (EC subclass 3.5) and similar acyl compounds.

dead
dead (ded)

1. Without life. SEE ALSO: death. 2. Numb.

DEAE-cellulose
DEAE-cellulose

SYN: O-diethylaminoethyl cellulose.

deaf
deaf (def)

Unable to hear. [A.S. deáf]

deafferentation
deafferentation (de-af′er-en-ta′shun)

A loss of the sensory input from a portion of the body, usually caused by interruption of the peripheral sensory fibers. [L. de, from, + afferent]

deafness
deafness (def′nes)

General term for inability to hear.
central d. d. due to disorder of the auditory system of the brainstem or cerebral cortex.
cortical d. d. resulting from bilateral lesions of the primary receptive area of the temporal lobe.
hereditary d. See hereditary hearing impairment.
nerve d., neural d. former terms for sensorineural hearing loss.
postlingual d. hearing impairment occurring after speech and language skills have been developed.
prelingual d. hearing impairment occurring before development of speech and language skills.
sudden d. a profound sensory hearing loss that develops in 24 hrs or less; generally thought to be due to a viral infection in the inner ear.
word d. SYN: auditory aphasia.

dealbation
dealbation (de-al-ba′shun)

The act of whitening, bleaching, or blanching. [L. de-albo, pp. -atus, to whiten]

dealcoholization
dealcoholization (de-al′ko-hol-i-za′shun)

The removal of alcohol from a fluid; in histologic technique, the removal of alcohol from a specimen that has been previously immersed in this fluid.

deallergize
deallergize (de-al′er-jiz)

Obsolete term for desensitize.

deamidases
deamidases (de-am′i-da-sez)

SYN: amidohydrolases.

deamidation
deamidation, deamidization (de-am-i-da′shun, de-am′i-di-za′shun)

The hydrolytic removal of an amide group.

deamidize
deamidize (de-am′i-diz)

To perform deamidation. SYN: desamidize.

deaminases
deaminases (de-am′i-na-sez) [EC 3.5.4.x]

Enzymes catalyzing simple hydrolysis of C&cbond;NH₂ bonds of purines, pyrimidines, and pterins, thus producing ammonia (usually named in terms of the substrate, e.g., guanine d., adenosine d., AMP d., pterin d.); not generally used for deamination of noncyclic amides. D. are distinguished from ammonia-lyases (EC 4.3.1.x) in that the latter produce an unsaturation at the point of NH₃ removal. SYN: deaminating enzymes.

deamination
deamination, deaminization (de-am-i-na′shun, de-am′i-ni-za′shun)

Removal, usually by hydrolysis, of the NH₂ group from an amino compound.
oxidative d. d. by enzymes that uses flavin or pyridine nucleotides (such as FAD or NAD⁺).

deaminize
deaminize (de-am′i-niz)

To perform deamination.

Dean
Dean

Henry Trendley, U.S. dentist and epidemiologist, 1893–1962. See D. fluorosis index.

deanol acetamidobenzoate
deanol acetamidobenzoate (de′a-nol as-e-tam′i-do-ben′zo-at)

The p-acetamidobenzoic acid salt of 2-dimethylaminoethanol; a central nervous system stimulant.

death
death (deth)

The cessation of life. In lower multicellular organisms, d. is a gradual process at the cellular level, because tissues vary in their ability to withstand deprivation of oxygen; in higher organisms, a cessation of integrated tissue and organ functions; in humans, manifested by the loss of heartbeat, by the absence of spontaneous breathing, and by cerebral d.. SYN: mors. [A.S. d.]
black d. term applied to the worldwide epidemic of the 14th century, of which some 60 million persons are said to have died; the descriptions indicate that it was pneumonic plague.
brain d. SYN: cerebral d..
cerebral d. a clinical syndrome characterized by the permanent loss of cerebral and brainstem function, manifested by absence of responsiveness to external stimuli, absence of cephalic reflexes, and apnea. An isoelectric electroencephalogram for at least 30 minutes in the absence of hypothermia and poisoning by central nervous system depressants supports the diagnosis. SYN: brain d..
d. certificate official, legal document and vital record, signed by a licensed physician or other designated authority, that includes cause of d., decedent's name, sex, place of residence, date of d.; other information, e.g., birth date, birth place, occupation may be included; the immediate cause of d. is recorded on the first line of the certificate, followed by the condition(s) giving rise to this, with the underlying cause on the last line; the underlying cause is coded and tabulated in official publications of mortality.
cot d. SYN: sudden infant d. syndrome.
crib d. SYN: sudden infant d. syndrome.
crude d. rate SYN: d. rate.
fetal d. d. prior to the complete expulsion or extraction from the mother of a product of conception, irrespective of the duration of pregnancy. Fetal d. is considered early if it takes place in the first 20 weeks of gestation; middle (intermediate) if it takes place from 21–28 weeks of gestation, and late if it takes place after 28 weeks.
genetic d. d. of the bearer of a gene at any age before generating living offspring. May be compatible with good health and long life. SEE ALSO: genetic lethal.
infant d. d. of a liveborn infant within the first year.
local d. d. of a part of the body or of a tissue by necrosis.
maternal d. d. of a woman while pregnant or within 42 days after the termination of gestation, irrespective of the duration and site of pregnancy and the cause of d.; two periods are recognized in the 42-day interval: period one includes day 1 to day 7; period two includes day 8 to day 42. Maternal deaths are further classified as: direct maternal d., d. resulting from obstetric complications of the gestation, labor, or puerperium, and from interventions, omissions, incorrect treatment, or a chain of events caused by any of the above; indirect maternal d., an obstetric d. resulting from previously existing disease or from disease developing during pregnancy, labor, or the puerperium; it is not directly due to obstetric causes, but to conditions aggravated by the physiologic effects of pregnancy.
neonatal d. d. of a young, liveborn infant; classified as: early neonatal d., d. of a liveborn infant occurring fewer than 7 completed days (168 hours) from the time of birth; late neonatal d., d. of a liveborn infant occurring after 7 completed days of age but before 28 completed days.
perinatal d. an inclusive term referring to both stillborn infants and neonatal deaths.
programmed cell d. SYN: apoptosis.
somatic d., systemic d. d. of the entire body, as distinguished from local d..
sudden d. d. occurring rapidly and generally unexpectedly; usually from a cardiac dysrhythmia or myocardial infarction, but also from any cause of rapid d., e.g., pulmonary embolus, stroke, ruptured aortic aneurysm, aortic dissection.

death-rattle
death-rattle (deth′rat′l)

A respiratory gurgling or rattling in the pharynx or trachea of a dying person, caused by the loss of the cough reflex and accumulation of mucus.

Deaver
Deaver

John Blair, U.S. surgeon, 1855–1931. See D. incision.

Deaver
Deaver

George G., U.S. physiatrist, 1890–1973. See D. method.

DeBakey
DeBakey

Michael Ellis, U.S. heart surgeon, *1908. See D. classification, D. forceps.

debanding
debanding (de-band′ing)

The removal of fixed orthodontic appliances.

debilitant
debilitant (de-bil′i-tant)

1. Weakening; causing debility. 2. Obsolete term for a quieting agent or one that subdues excitement. [L. debilito, to weaken, fr. de, neg., + habilis, able]

debilitating
debilitating (de-bil′i-tat-ing)

Denoting or characteristic of a morbid process that causes weakness.

debility
debility (de-bil′i-te)

Weakness. [L. debilitas, fr. debilis, weak, fr. de- priv. + habilis, able]

debond
debond (de-bond′)

To separate a dental appliance such as an orthodontic band from the tooth to which it has been attached or bonded by a resin cement. [de- + bond]

debouch
debouch (de-boosh′)

To open or empty into another part. [Fr. bouche, mouth]

débouchement
débouchement (da-boosh-mon′)

Opening or emptying into another part. [Fr.]

Debré
Debré

Robert, French pediatrician and infectious disease specialist, 1882–1978. See Debré phenomenon, Debré-Sémélaigne syndrome, Kocher-Debré-Sémélaigne syndrome.

débridement
débridement (da-bred-mon′)

Excision of devitalized tissue and foreign matter from a wound. [Fr. unbridle]

debris
debris (de-bre)

A useless accumulation of miscellaneous particles; waste in the form of fragments. [Fr. débris, fr. O.Fr. desbrisier, to break apart, (fr. des- down, away + brisier to break) rubble, rubbish]
particulate wear d. microscopic particles produced by friction between articulating surfaces in a total joint replacement; d. can include particles of metal, polyethylene, and polymethylmethacrylate cement, and can induce osteolysis.

debrisoquine sulfate
debrisoquine sulfate (de-bris′o-kwin)

An antihypertensive agent resembling guanethidine; also used in drug metabolism studies.

debt
debt (det)

A deficit; a liability. [L. debitum, d.]
alactic oxygen d. that part of the oxygen d. that is not lactacid oxygen d.; during recovery, stores of ATP and creatine phosphate must be replenished by oxidative metabolism, and a small amount of oxygen is also needed to restore the normal oxyhemoglobin levels throughout the circulating blood.
lactacid oxygen d. that part of an oxygen d. represented by the production of lactic acid by anaerobic glycolysis during exercise and, therefore, by the need to eliminate it by oxidative metabolism during recovery.
oxygen d. the extra oxygen, taken in by the body during recovery from exercise, beyond the resting needs of the body; sometimes used as if synonymous with oxygen deficit.

deca- deca- (da)

Prefix used in the SI and metric system to signify multiples of 10. Also spelled deka-. [G. deka, ten]

decagram
decagram (dek′a-gram)

Ten grams.

decalcification
decalcification (de′kal-si-fi-ka′shun)

1. Removal of lime or calcium salts, chiefly tricalcium phosphate, from bones and teeth, either in vitro or in vivo as a result of a pathologic process. 2. Precipitation of calcium from blood as by oxalate or fluoride, or the conversion of blood calcium to an un-ionized form as by citrate, thus preventing or delaying coagulation. [L. de-, away, + calx (calc-), lime, + facio, to make]

decalcify
decalcify (de-kal′si-fi)

To remove lime or calcium salts, especially from bones or teeth.

decalcifying
decalcifying (de-kal′si-fi-ing)

Denoting an agent, measure, or process that causes decalcification.

decaliter
decaliter (dek′a-le-ter)

Ten liters.

decalvant
decalvant (de-kal′vant)

Removing the hair; making bald. [L. decalvare, to make bald]

decameter
decameter (dek′a-me-ter)

Ten meters.

decamethonium bromide
decamethonium bromide (dek-a-me-tho′ne-um)

A synthetic nondepolarizing neuromuscular blocking agent used to produce muscular relaxation during general anesthesia.

decamine
decamine (dek′a-men)

SYN: dequalinium acetate.

decannulation
decannulation (de-kan-u-la′shun)

Planned or accidental removal of a tracheostomy tube.

decanoin
decanoin (dek-a-no′in)

SYN: caprin.

decanormal
decanormal (dek-a-nor′mal)

Rarely used term denoting the concentration of a solution 10 times that of normal.

decant
decant (de-kant′)

To pour off gently the upper clear portion of a fluid, leaving the sediment in the vessel. [Mediev. L. decantho, fr. de- + canthus, the beak of a jug, fr. G. kanthos, corner of the eye]

decantation
decantation (de-kan-ta′shun)

Pouring off the clear upper portion of a fluid, leaving a sediment or precipitate.

decapacitation
decapacitation (de′ka-pas-i-ta′shun)

Prevention of spermatozoa from undergoing capacitation and thus from becoming able to fertilize ova. SEE ALSO: d. factor.

decapeptide
decapeptide (dek′a-pep′tid)

An oligopeptide containing 10 amino acids.

decapitate
decapitate (de-kap′i-tat)

1. To cut off the head; specifically, to remove the head of a fetus to facilitate delivery in cases of irremediable dystocia; to cut off the head of an animal in preparation for certain physiologic experiments; obsolete term. 2. Relating to an experimental animal with the head removed. [L. de-, away, + caput, head]

decapitation
decapitation (de-kap-i-ta′shun)

Removal of a head. See decapitate.

decapsulation
decapsulation (de-kap-soo-la′shun)

Incision and removal of a capsule or enveloping membrane.
d. of kidney removing or stripping off the capsule of the kidney.

decarbonization
decarbonization (de-kar′bon-i-za′shun)

Rarely used term denoting the process of arterialization of the blood by oxygenation and the removal of carbon dioxide in the lungs.

decarboxylase
decarboxylase (de-kar-boks′e-las)

Any enzyme (EC 4.1.1.x) that removes a molecule of carbon dioxide from a carboxylic group ( e.g., from an α-amino acid, converting it into an amine).

decarboxylation
decarboxylation (de′kar-boks-e-la′shun)

A reaction involving the removal of a molecule of carbon dioxide from a carboxylic acid.
oxidative d. d. requiring the participation of coenzymes such as NAD⁺, NADP⁺, FAD, or FMN.

decay
decay (de-ka′)

1. Destruction of an organic substance by slow combustion or gradual oxidation. 2. SYN: putrefaction. 3. To deteriorate; to undergo slow combustion or putrefaction. 4. In dentistry, caries. 5. In psychology, loss of information registered by the senses and processed into short-term memory. SEE ALSO: memory. 6. Loss of radioactivity with time; spontaneous emission of radiation or charged particles or both from an unstable nucleus. [L. de, down, + cado, to fall]
free induction d. (FID) in magnetic resonance imaging, the d. curve that is detected by the receiver coil after the application of an excitation pulse, without additional pulses.

deceleration
deceleration (de-sel-er-a′shun)

1. The act of decelerating. 2. The rate of decrease in velocity per unit of time.
early d. slowing of the fetal heart rate early in the uterine contraction phase, denoting compression of the fetal head.
late d. any transient fetal bradycardia, the nadir of which occurs after the peak of the uterine contraction. This may represent uteroplacental insufficiency.
variable d. transient fetal bradycardia usually denoting compression of the umbilical cord, which may occur at any time in relation to a uterine contraction.

decentration
decentration (de-sen-tra′shun)

Removal from the center.

decerebrate
decerebrate (de-ser′e-brat)

1. To cause decerebration. 2. Denoting an animal so prepared, or a patient whose brain has suffered an injury which renders the patient, in neurologic behavior, comparable to a d. animal.

decerebration
decerebration (de-ser′e-bra′shun)

Removal of the brain above the lower border of the corpora quadrigemina, or a complete section of the brain at this level or somewhat below.
bloodless d. destroying the function of the cerebrum by tying the basilar artery at about the middle of the pons and the common carotid arteries in the neck.

decerebrize
decerebrize (de-ser′e-briz)

To remove the brain.

dechloridation
dechloridation (de′klor-i-da′shun)

Reduction of sodium chloride in the tissues and fluids of the body by reducing its intake or increasing its excretion. SYN: dechlorination, dechloruration.

dechlorination
dechlorination (de′klor-i-na′shun)

SYN: dechloridation.

dechloruration
dechloruration (de′klor-oo-ra′shun)

SYN: dechloridation.

decholesterolization
decholesterolization (de′ko-les′ter-ol-i-za′shun)

Therapeutic reduction of the cholesterol concentration of the blood.

deci- deci- (d)

Prefix used in the SI and metric system to signify one-tenth (10⁻¹). [L. decimus, tenth]

decibel
decibel (dB, db) (des′i-bel)

One-tenth of a bel; unit for expressing the relative intensity of sound on a logarithmic scale. [L. decimus, tenth, + bel]

decidua
decidua (de-sid′u-a)

SYN: deciduous membrane. [L. deciduus, falling off (qualifying membrana, membrane, understood)]
d. basalis the area of endometrium between the implanted chorionic vesicle and the myometrium, which develops into the maternal part of the placenta. SYN: d. serotina.
d. capsularis the layer of endometrium overlying the implanted chorionic vesicle; it becomes progressively attenuated as the chorionic vesicle enlarges and, by the fourth month, is squeezed against the d. parietalis and thereafter undergoes rapid regression. SYN: d. reflexa, membrana adventitia (2) .
ectopic d. decidual cells which may be found in the cervix, appendix, or areas other than the endometrium.
d. menstrualis the succulent mucous membrane of the nonpregnant uterus at the menstrual period.
d. parietalis the altered mucous membrane lining the main cavity of the pregnant uterus other than at the site of attachment of the chorionic vesicle. SYN: d. vera.
d. polyposa d. parietalis showing polypoid projections of the endometrial surface.
d. reflexa SYN: d. capsularis.
d. serotina SYN: d. basalis.
d. spongiosa the portion of the d. basalis attached to the myometrium.
d. vera SYN: d. parietalis.

decidual
decidual (de-sid′u-al)

Relating to the decidua.

deciduate
deciduate (de-sid′u-at)

Relating to those mammals ( e.g., humans, dogs, rodents) that shed maternal uterine tissue when expelling the placenta at birth, in contrast to indeciduate mammals (horse, pig). [see deciduation]

deciduation
deciduation (de-sid-u-a′shun)

Shedding of endometrial tissue during menstruation. [L. deciduus, falling off]

deciduitis
deciduitis (de-sid-u-i′tis)

Inflammation of the decidua.

deciduoma
deciduoma (de-sid-u-o′ma)

An intrauterine mass of decidual tissue, probably the result of hyperplasia of decidual cells retained in the uterus. SYN: placentoma.
Loeb d. mass of decidual tissue produced in the uterus, in the absence of a fertilized ovum, by means of mechanical or hormonal stimulation.

deciduous
deciduous (de-sid′u-us)

1. Not permanent; denoting that which eventually falls off. 2. (D) (in dental formulas)In dentistry, often used to designate the first or primary dentition. See d. tooth. [L. deciduus, falling off]

decigram
decigram (des′i-gram)

One-tenth of a gram.

deciliter
deciliter (des′i-le-ter)

One-tenth of a liter.

decimeter
decimeter (des′i-me-ter)

One-tenth of a meter.

decimorgan
decimorgan (des′i-mor-gan)

See morgan.

decinormal
decinormal (des-i-nor′mal)

One-tenth of normal, denoting the concentration of a solution.

decision
decision

limiting d. an understanding of self achieved as a result of response to a significant or traumatic event. SEE ALSO: Time-Line therapy.

decision tree
decision tree

Alternative choices available at each stage of deciding how to manage a clinical problem, displayed graphically; at each branch or decision node, the probabilities of each outcome that can be predicted are shown; the relative worth of each outcome is described in terms of its utility or quality of life, e.g., as measured by probability of death, life expectancy, or freedom from disability.

de Clerambault
de Clerambault

G., French psychiatrist, 1872–1934. See de Clerambault syndrome.

declinator
declinator (dek′lin-a-ter, -tor)

A retractor that holds certain structures out of the way during an operation.

declive
declive (de-kliv′) [TA]

The posterior sloping portion of the monticulus of the vermis of the cerebellum; vermal lobule immediately caudal to the primary fissure; lobule VI. SYN: declivis, lobulus clivi. [L. declivis, sloping downward, fr. clivus, a slope]

declivis
declivis (de-kli′vis)

SYN: declive.

decoction
decoction (de-kok′shun)

1. The process of boiling. 2. The pharmacopeial name for preparations made by boiling crude vegetable drugs, and then straining, in the proportion of 50 g of the drug to 1000 mL of water. SYN: apozem, apozema. [L. decoctio, fr. de-coquo, pp. -coctus, to boil down]

décollement
décollement (da-kul-mon′)

Rarely used term for surgical separation of tissues or organs which are adherent, either normally or pathologically. [Fr. ungluing]

decompensation
decompensation (de′kom-pen-sa′shun)

1. A failure of compensation in heart disease. 2. The appearance or exacerbation of a mental disorder due to failure of defense mechanisms.
corneal d. corneal edema resulting from failure of the corneal endothelium to maintain deturgescence.

decompose
decompose (de′kom-poz)

1. To resolve a compound into its component parts; to disintegrate. 2. To decay; to putrefy. [L. de, from, down, + com-pono, pp. -positus, to put together]

decomposition
decomposition (de′kom-po-zish′un)

SYN: putrefaction.

decompression
decompression (de′kom-presh-un)

Removal of pressure. [L. de-, from, down, + com-primo, pp. -pressus, to press together]
cardiac d. incision into the pericardium or aspiration of fluid from the pericardium to relieve pressure due to blood or other fluid in the pericardial sac. SYN: pericardial d..
cerebral d. removal of a piece of the cranium, with incision of the dura, to relieve intracranial pressure.
explosive d. SYN: rapid d..
internal d. removal of intracranial tissue, usually tumor, hematoma, or brain tissue; to relieve pressure.
nerve d. release of pressure on a nerve trunk by the surgical excision of constricting bands or widening of a bony canal.
optic nerve sheath d. a venting of the optic nerve sheath into the retrobulbar space, by slitting or by fenestrating the sheath. See optic nerve sheath fenestration.
orbital d. removal of a portion of the bony orbit, usually superior (Naffziger operation), lateral (Krönlein operation), or inferior (Ogura operation).
pericardial d. SYN: cardiac d..
rapid d. sudden severe expansion of gases due to a reduction in ambient pressure. SYN: explosive d..
spinal d. the removal of pressure upon the spinal cord as created by a tumor, cyst, hematoma, herniated nucleus pulposus, abscess, or bone.
suboccipital d. d. of the posterior fossa by occipital craniectomy and opening of the dura.
subtemporal d. d. of the brain by temporal craniectomy and opening of the dura over the inferolateral surface of the temporal lobe.
trigeminal d. d. of the trigeminal nerve root.

decongestant
decongestant (de-kon-jes′tant)

1. SYN: decongestive. 2. An agent that possesses this action.

decongestive
decongestive (de-kon-jes′tiv)

Having the property of reducing tissue swelling. SYN: decongestant (1) .

decontamination
decontamination (de′kon-tam-i-na′shun)

Removal or neutralization of poisonous gas or other injurious agents from the environment.

deconvolution
deconvolution (de-con-vo-loo′shun)

A mathematic technique for solution of functions whose input includes their output; used to solve for the image elements in computed tomography or magnetic resonance imaging. [de- + L. convulutio, a rolling up, fr. convolvo, to roll up]

decortication
decortication (de-kor-ti-ka′shun)

1. Removal of the cortex, or external layer, beneath the capsule from any organ or structure. 2. An operation for removal of the residual clot and/or newly organized scar tissue that form after a hemothorax or neglected empyema. [L. decortico, pp. -atus, to deprive of bark, fr. de, from, + cortex, rind, bark]
cerebral d. destruction of the cerebral cortex, usually due to anoxia.
reversible d. a temporary loss of function of the cerebral cortex.

decrement
decrement (dek′re-ment)

1. Decrease. 2. Decrease in conduction velocity at a particular point; a result of altered properties at that point. SEE ALSO: decremental conduction. [L. decrementum, fr. decresco, to decrease]

decrepitation
decrepitation (de-krep-i-ta′shun)

Crackling; the snapping of certain salts when heated. [L. de, from, + crepo, pp. crepitus, to crackle]

decrudescence
decrudescence (de-kroo-des′ens)

Abatement of the symptoms of disease. [L. de, from, + crudesco, to become worse, fr. crudus, crude]

decubital
decubital (de-ku′bi-tal)

Relating to a decubitus ulcer.

decubitus
decubitus (de-ku′bi-tus)

1. The position of the patient in bed; e.g., dorsal d., lateral d.. See d. film. 2. Sometimes used in referring to a d. ulcer. [L. decumbo, to lie down]
Andral d. position assumed by the patient who lies on the sound side in cases of beginning pleurisy.
ventral d. pressure sores (d. ulceration) occurring in ventral locations, such as the abdominal wall or the anterior surface of an extremity.

decurrent
decurrent (de-kur′ent)

Extending downward. [L. de-curro, pp. -cursus, to run down]

decussate
decussate (de′ku-sat, de-kus′at)

1. To cross. 2. Crossed like the arms of an X. [L. decusso, pp. -atus, to make in the form of an X, fr. decussis, a large, bronze Roman (2nd c. BC), 10-unit coin marked with an X to indicate its denomination]

decussatio
decussatio, pl .decussationes (de-ku-sa′she-o, -o′nez) [TA]

1. In general, any crossing over or intersection of parts. 2. The intercrossing of two homonymous fiber bundles as each crosses over to the opposite side of the brain in the course of its ascent or descent through the brainstem or spinal cord. SYN: decussation. [L. (see decussate)]
d. brachii conjunctivi SYN: decussation of superior cerebellar peduncles.
d. fibrarum nervorum trochlearium [TA] SYN: decussation of trochlear nerve fibers.
d. fontinalis decussationes tegmentales.
d. lemnisci mediales [TA] SYN: decussation of medial lemniscus.
d. motoria SYN: decussation of pyramids.
d. pedunculorum cerebellarium superiorum [TA] SYN: decussation of superior cerebellar peduncles.
d. pyramidum [TA] SYN: decussation of pyramids.
d. sensoria SYN: decussation of medial lemniscus.
decussationes tegmentales [TA] SYN: tegmental decussations, under decussation.
d. tegmentalis anterior [TA] See tegmental decussations, under decussation.
d. tegmentalis posterior [TA] See tegmental decussations, under decussation.

decussation
decussation (de-ku-sa′shun)

SYN: decussatio. [L. decussatio]
anterior tegmental d. [TA] See tegmental decussations (2) .
d. of brachia conjunctiva SYN: d. of superior cerebellar peduncles.
dorsal tegmental d. [TA] See tegmental decussations.
d. of the fillet SYN: d. of medial lemniscus.
Forel d. tegmental decussations (2) .
fountain d. tegmental decussations (1) .
Held d. the crossing of some of the fibers arising from the cochlear nuclei to form the lateral lemniscus.
d. of medial lemniscus the intercrossing of the fibers of the left and right medial lemniscus ascending from the gracile and cuneate nuclei, immediately rostral to the level of the d. of the pyramidal tracts in the medulla oblongata. SYN: decussatio lemnisci mediales [TA] , decussatio sensoria, d. of the fillet, sensory d. of medulla oblongata.
Meynert d. tegmental decussations (1) .
motor d. SYN: d. of pyramids.
optic d. SYN: optic chiasm.
posterior tegmental d. [TA] tegmental decussations (1) .
d. of pyramids [TA] the intercrossing of the bundles of corticospinal fibers at the lower border region of the medulla oblongata. SYN: decussatio pyramidum [TA] , decussatio motoria, motor d..
rubrospinal d. tegmental decussations (2) .
sensory d. of medulla oblongata SYN: d. of medial lemniscus.
d. of superior cerebellar peduncles [TA] the d. of the left and right superior cerebellar peduncles in the tegmentum of the caudal mesencephalon. SYN: decussatio pedunculorum cerebellarium superiorum [TA] , decussatio brachii conjunctivi, d. of brachia conjunctiva, Wernekinck d..
tectospinal d. tegmental decussations (1) .
tegmental decussations 1. the posterior tegmental d. [TA] (dorsal tegmental d. [TA], fountain d., Meynert's d.) is formed by the crossing of the left and right tectospinal and tectobulbar tracts; 2. the anterior tegmental d. [TA] (ventral tegmental d. [TA], Forel's d.) is formed by the crossing of the left and right rubrospinal and rubrobulbar tracts; both decussations are located in the mesencephalon. SYN: decussationes tegmentales [TA] .
d. of trochlear nerve fibers [TA] the crossing of the two trochlear nerves at their exit through the velum medullare anterius. SYN: decussatio fibrarum nervorum trochlearium [TA] .
ventral tegmental d. See tegmental decussations (2) .
Wernekinck d. SYN: d. of superior cerebellar peduncles.

decussationes
decussationes (de-kus-a-she-o′nez)

Plural of decussatio.

dedentition
dedentition (de-den-tish′un)

Obsolete term denoting loss of teeth.

dedifferentiation
dedifferentiation (de-dif′er-en-she-a′shun)

1. The return of parts to a more homogeneous state. 2. SYN: anaplasia.

dedolation
dedolation (de-do-la′shun)

A slicing wound made by a sharp instrument grazing the surface. [L. de-dolo, pp. -atus, to hew away]

deduction
deduction (de-duk′shun)

The logical derivation of a conclusion from certain premises. The conclusion will be true if the premises are true and the deductive argument is valid. Cf.:induction (9) .

de-efferentation
de-efferentation (de-ef-er-en-ta′shun)

A loss of the motor nerve fibers to an area of the body. [L. de, from, + efferent]

deep
deep (dep) [TA]

Situated at a deeper level in relation to a specific reference point. Cf.:superficialis. SYN: profundus [TA] .

de-epicardialization
de-epicardialization (de-ep-i-kar′de-al-i-za′shun)

Obsolete surgical destruction of the epicardium, usually by the application of phenol, designed (unsuccessfully) to promote collateral circulation to the myocardium.

Deetjen
Deetjen

Hermann, German physician, 1867–1915. See D. bodies, under body.

def
def, DEF

Abbreviation for decayed, extracted, and filled tooth. See d. caries index.

defatigation
defatigation (de-fat-i-ga′shun)

Weariness, exhaustion, or extreme fatigue. [L. de-fatigo, pp. -atus, to tire out]

defecate
defecate (def′e-kat)

To perform defecation.

defecation
defecation (def-e-ka′shun)

The discharge of feces from the rectum. SYN: motion (2) , movement (3) . [L. defaeco, pp. -atus, to remove the dregs, purify]

defecography
defecography (de-fe-kog′ra-fe)

Radiographic examination of the act of defecation of a radiopaque stool. [defecation + G. grapho, to write]

defect
defect (de′fekt)

An imperfection, malformation, dysfunction, or absence; an attribute of quality, in contrast with deficiency, which is an attribute of quantity. [L. deficio, pp. -fectus, to fail, to lack]
aortic septal d., aorticopulmonary septal d. a small congenital opening between the aorta and pulmonary artery about 1 cm above the semilunar valves, e.g., aorticopulmonary window. SYN: aorticopulmonary window.
atrial septal d. a congenital d. in the septum between the atria of the heart, due to failure of the foramen primum or secundum to close normally; may involve atrioventricular canal cushions; occasionally there is strong evidence of autosomal dominant inheritance [MIM*108800]. In varying degree, it is also a common feature of the autosomal recessive Ellis-van Creveld syndrome [MIM*225500] and the autosomal dominant Holt-Oram syndrome [MIM*142900].
atrial ventricular canal d. a d. caused by deficient or absent septal tissue immediately above and below the normal level of the atrioventricular valves, including the region normally occupied by the A-V septum in hearts with two ventricles. The A-V valves are abnormal to a varying degree.
birth d. d. present at birth; sometimes referred to as congenital d..
congenital ectodermal d. SYN: congenital ectodermal dysplasia.
coupling d. familial goiter.
Eisenmenger d. SYN: Eisenmenger complex.
endocardial cushion d. SYN: persistent atrioventricular canal.
fibrous cortical d. a common 1 to 3 cm d. in the cortex of a bone, most commonly the lower femoral shaft of a child, filled with fibrous tissue. Nonosteogenic or nonossifying fibroma by convention refers to lesions greater than 3 cm in diameter. SEE ALSO: nonossifying fibroma. SYN: nonosteogenic fibroma.
filling d. displacement of contrast medium by a space-occupying lesion in a radiographic study of a contrast-filled hollow viscus, such as a polyp on a barium enema; also applied to defects in the otherwise uniform distribution of radionuclide in an organ, such as a metastasis in the liver on a ^99mTc-sulfur colloid scan.
Gerbode d. a d. in the interventricular portion of the membranous septum, associated with a communication between the right ventricle and the right atrium through an abnormality in the tricuspid valve.
iodide transport d. familial goiter.
iodotyrosine deiodinase d. familial goiter.
luteal phase d. a condition characterized by inadequate secretion of progesterone during the luteal phase of the menstrual cycle, with resultant infertility; subnormal luteal function commonly attributed to abnormal pituitary gonadotropin secretion. SYN: luteal phase deficiency.
metaphyseal fibrous cortical d. a small fibrous cortical d. located in the metaphysis of a long bone.
organification d. familial goiter.
osteoporotic marrow d. (os′te-o-po-ro′tik) focal osteoporotic bone marrow d. of the jaw; a focal radiolucent d. composed of normal marrow.
postinfarction ventricular septal d. a d. developed in the ventricular septum resulting from rupture of an acute myocardial infarction.
relative afferent pupillary d. relative afferent pupillary d..
salt-losing d. renal tubular abnormality causing loss of sodium in the urine.
ventricular septal d. a congenital d. in the septum (membranous or muscular) between the cardiac ventricles, usually resulting from failure of the spiral septum to close the interventricular foramen.

defective
defective (de-fek′tiv)

Denoting or exhibiting a defect; imperfect; a failure of quality.

defemination
defemination (de-fem-i-na′shun)

A weakening or loss of feminine characteristics. [L. de-, away, + femina, woman]

defense
defense (de-fens′)

The psychological mechanisms used to control anxiety, e.g., rationalization, projection. [L. defendo, to ward off]
screen d. the use of falsified or incomplete memories or affects to cover repressed but associated memories and affects.
ur-defenses ur-defenses.

defensins
defensins (de-fen′sinz)

A class of basic antibiotic polypeptides, found in neutrophils, that kill bacteria by causing membrane damage. These cytotoxic peptides contain 29–38 amino acid residues. [L. de-fendo, pp. de-fensum, to repel, avert, + -in]

deferent
deferent (def′er-ent)

Carrying away. [L. deferens, pres. p. of defero, to carry away]

deferential
deferential (def-er-en′shal)

Relating to the ductus deferens.

deferentitis
deferentitis (def′er-en-ti′tis)

Inflammation of the ductus deferens. SYN: vasitis.

deferoxamine mesylate
deferoxamine mesylate (de-fer-ok′sa-men)

Chelate used in the treatment of iron poisoning. SYN: desferrioxamine mesylate.

defervescence
defervescence (def-er-ves′ens)

Falling of an elevated temperature; abatement of fever. [L. de-fervesco, to cease boiling, fr. de- neg. + fervesco, to begin to boil]

defibrillation
defibrillation (de-fib-ri-la′shun)

The arrest of fibrillation of the cardiac muscle (atrial or ventricular) with restoration of the normal rhythm, if successful.

defibrillator
defibrillator (de-fib′ri-la-ter)

1. Any agent or measure, e.g., an electric shock, that arrests fibrillation of the ventricular muscle and restores the normal beat. 2. The machine designed to administer a defibrillating electric shock.
external d. a d. that delivers its defibrillating shock through the unopened chest wall.

defibrination
defibrination (de-fi-bri-na′shun)

Removal of fibrin from the blood, usually by means of constant agitation while the blood is collected in a container with glass beads or chips.

deficiency
deficiency (de-fish′en-se)

An insufficient quantity of some substance (as in dietary d. or hemoglobin d. in marrow aplasia); organization (as in mental d.); activity (as in enzyme d. or reduced oxygen-carrying capacity of the blood), etc., of which the amount present is of normal quality. SEE ALSO: d. disease. [L. deficio, to fail, fr. facio, to do]
adult lactase d. onset of lactase d., with resulting milk intolerance and malabsorption, in adulthood. Inherited forms may not be manifested until adulthood; any process that damages the intestinal lining cells can cause lactase d. in adults.
antitrypsin d. d. of α₁-antitrypsin, a serum protease inhibitor (PI), is associated with emphysema and/or liver cirrhosis. By isoelectric focusing, numerous variants have been identified, with different levels of normal activity; autosomal recessive inheritance, caused by mutation in the P1 gene on chromosomal 14q.
α₁-antitrypsin d. absence of a serum proteinase inhibitor that may cause relapsing nodular nonsuppurative panniculitis.
arch length d. the difference between the available circumference of the dental arch and that required to accommodate the succedaneous teeth in proper alignment.
arginosuccinate lyase d. SYN: argininosuccinic aciduria.
arylsulfatase A d. SYN: metachromatic leukodystrophy.
arylsulfatase B d. SYN: Maroteaux-Lamy syndrome.
biotinidase d. a rare, autosomal recessive disease causing loss of excessive biotin; clinical manifestations may be absent, but extreme manifestations include seizures, alopecia, dermatitis, hypotonia, optic atrophy, ataxia, developmental delay, hearing deficits, and occasionally immunodeficiency; trait has a prevalence of 1 in 60,000.
carnitine d. a condition associated with many disorders of fatty acid oxidation. Fatty acids are linked to carnitine as they are transported across the inner mitochondrial membrane; errors in this process lead to problems with energy production; patients may experience episodes of hypoglycemia or metabolic acidosis and may have cardiomyopathy or skeletal muscle weakness.
debrancher d. SYN: brancher glycogen storage disease.
familial high density lipoprotein d. SYN: analphalipoproteinemia.
fructokinase d. SYN: essential fructosuria.
galactokinase d. [MIM*230200] an inborn error of metabolism due to congenital d. of galactokinase (GALK), resulting in increased blood galactose concentration (galactosemia), cataracts, hepatomegaly, and mental d.; autosomal recessive inheritance, caused by mutation in the GALK gene on 17q. Galactose epimerase d. [MIM*230350] and galactose-1-phosphate uridyl transferase d. [MIM*230400] produce much the same clinical picture.
glucose-6-phosphate dehydrogenase d. a d. of glucose-6-phosphate dehydrogenase, an enzyme important for maintaining cellular concentrations of reduced nucleotides. An X-linked disorder with various polymorphic forms, it can cause a variety of anemias including favism, primaquine sensitivity and other drug sensitivity anemias, anemia of the newborn, and chronic nonspherocytic hemolytic anemia.
glucosephosphate isomerase d. [MIM*172400] an enzyme d. characterized by chronic nonspherocytic hemolytic anemia; autosomal recessive inheritance. SYN: phosphohexose isomerase d..
β-d-glucuronidase d. a rare d. of β-d-glucuronidase; an autosomal recessive disorder with several allelic forms, characterized by abnormal mucopolysaccharide metabolism leading to progressive mental deterioration, splenic and hepatic enlargement, and dysostosis multiplex. SYN: mucopolysaccharidase.
glutathione synthetase d. an inborn error of metabolism associated with massive urinary excretion of 5-oxyproline, elevated levels of 5-oxyproline in the blood and cerebrospinal fluid, severe metabolic acidosis, tendency toward hemolysis, and defective central nervous systems function. Glutathione synthetase d. has been reported as a generalized condition or with a d. restricted to erythrocytes.
11-hydroxylase d. a type of congenital adrenal hyperplasia, with multiple manifestations, including hypertensive types and salt-wasting varieties.
21-hydroxylase d. one form of congenital adrenal hyperplasia, with variable presentations, including simple virilizing, salt-wasting, or nonclassic types.
hypoxanthine guanine phosphoribosyltransferase d. a sex-linked inherited metabolic disorder; complete d. results in Lesch-Nyhan syndrome; incomplete d. is associated with acute gouty arthritis and renal stones.
immune d. SYN: immunodeficiency.
immunity d. SYN: immunodeficiency.
immunologic d. SYN: immunodeficiency.
LCAT d. a rare condition characterized by corneal opacities, hemolytic anemia, proteinuria, renal insufficiency, and premature atherosclerosis, and very low levels of lecithin cholesterol acyltransferase (LCAT) activity; results in accumulation of unesterfied cholesterol in plasma and tissues.
leukocyte adhesion d. (LAD) an inherited disorder (autosomal recessive) in which there is a defective CD18 adherence complex that disturbs chemotaxis. It is characterized by recurrent bacterial pyogenic infections and impaired wound healing.
long-chain 3-hydroxyacyl-CoA dehydrogenase d. a fatty acid oxidation disorder; patients may experience episodes of acute hypoketotic hypoglycemia (similar to that found in MCAD d.), cardiomyopathy, muscle weakness, and liver abnormalities.
long-chain/very long-chain acyl-CoA dehydrogenase d. a disorder of fatty acid oxidation in patients who lack the enzyme very long chain acyl-CoA dehydrogenase; sometimes manifested as weakness, hypotonia, cardiomyopathy, rhabdomyolysis, and episodes of hypoglycemia during fasting.
luteal phase d. SYN: luteal phase defect.
medium-chain acyl-CoA dehydrogenase d. the most common fatty acid oxidation disorder, presenting as acute episodes triggered by prolonged fasting for more than 12–16 hours, with hypoglycemia, vomiting, and lethargy, which may progress to seizures, coma, or cardiopulmonary collapse, usually presenting before age 3.
mental d. SYN: mental retardation.
muscle phosphorylase d. type V glycogen storage disease, affecting muscle, caused by d. of muscle phosphorylase.
phosphohexose isomerase d. SYN: glucosephosphate isomerase d..
placental sulfatase d. an enzyme defect in the placenta which results in failure of conversion of 16α-hydroxydehydroepiandrosterone to estriol; women with this condition rarely enter into spontaneous labor.
primary carnitine d. a rare defect in carnitine metabolism due to a defect in carnitine transport; patients may present with hypoketotic hypoglycemia and develop cardiomyopathy or skeletal muscle weakness.
proximal femoral focal d. (PFFD) a congenital defect in which variable portions of the upper end of the femur are reduced or absent.
pseudocholinesterase d. [MIM*177400] an autosomal dominant disorder manifested by exaggerated responses to drugs ordinarily hydrolyzed by serum pseudocholinesterase ( e.g., succinylcholine); believed to entail production of a variant enzyme that is less active than the normal enzyme in hydrolyzing appropriate substrates, but also abnormally resistant to the effects of anticholinesterases, caused by mutation in the pseudocholinesterase E1 gene (CHE1) on 3q.
pyruvate kinase d. [MIM*266200] a disorder in which there is a d. of pyruvate kinase in red blood cells; characterized by hemolytic anemia varying in degree from one patient to another; autosomal recessive inheritance, caused by mutation in the pyruvate kinase liver and red blood cell gene (PKLR) on chromosome 1q.
riboflavin d. ariboflavinosis.
secondary antibody d. SYN: secondary immunodeficiency.
short-chain acyl-CoA dehydrogenase d. a disorder of fatty acid oxidation; patients may have chronic acidosis, failure to thrive, muscle weakness, and developmental delay.
taste d. [MIM*171200] reduced or absent ability to detect a bitter taste in a group of compounds of which phenylthiocarbamide is the prototype, due to the homozygous state of a common allele. SEE ALSO: phenylthiourea.

deficit
deficit (def′i-sit)

The result of consuming or using something faster than it is being replenished or replaced. [L. deficio, to fail]
base d. a decrease in the total concentration of blood buffer base, indicative of metabolic acidosis or compensated respiratory alkalosis.
oxygen d. the difference between oxygen uptake of the body during early stages of exercise and during a similar duration in a steady state of exercise; sometimes considered as the formation of the oxygen debt.
pulse d. 1. the absence of palpable pulse waves in a peripheral artery for one or more heart beats, as is often seen in atrial fibrillation; 2. the number of such missing pulse waves (usually expressed as heart rate minus pulse rate per minute).
sleep d. a lack of sleep time or a relative lack of one of the stages of sleep as determined by a sleep study.

definition
definition (def′i-nish′un)

In optics, the power of a lens to give a distinct image. SEE ALSO: resolving power. [L. de-finio, pp. -finitus, to bound, fr. finis, limit]

deflection
deflection (de-flek′shun)

1. A moving to one side. 2. In the electrocardiogram, a deviation of the curve from the isoelectric base line; any wave or complex of the electrocardiogram. [L. de-flecto, pp. -flexus, to bend aside]
intrinsic d. with the electrode in direct contact with the muscle fiber, a rapid downward d. from the peak of latest positivity, signifying that the activation front has reached the subjacent muscle.
intrinsicoid d. the abrupt downstroke from latest positivity when the electrode is placed not directly on the muscle but at a distance, as in the unipolar chest leads in clinical electrocardiography.

deflexion
deflexion (de′fleks-shun)

Term used to describe the position of the fetal head in relation to the maternal pelvis in which the head is descending in a nonflexed or extended attitude. [de- + L. flexio, a bending, fr. flecto, pp. flexum, to bend]

deflorescence
deflorescence (de-flo-res′ens)

Disappearance of the eruption in scarlet fever or other exanthemas. [L. de-floresco, to fade, wither, fr. flos (flor-), flower]

defluoridation
defluoridation (de-flor′i-da′shun)

Removal of excess fluorides from a community water supply.

defluvium
defluvium (de-floo′ve-um)

SYN: defluxion. [L., fr. de-fluo, pp. -fluxus, to flow down]

defluxion
defluxion (de-fluk′shun)

1. A falling down or out, as of the hair. SEE ALSO: effluvium. 2. A flowing down or discharge of fluid. SYN: defluvium. [L. defluxio, de-fluo, pp. -fluxus, to flow down]

deformability
deformability (de-form′a-bil′i-te)

The ability of cells, such as erythrocytes, to change shape as they pass through narrow spaces, such as the microvasculature.

deformation
deformation (de-for-ma′shun)

1. Deviation of form from the normal; specifically, an alteration in shape and/or structure of a previously normally formed part. It occurs after organogenesis and often involves the musculoskeletal system ( e.g., clubfoot). 2. In rheology, the change in the physical shape of a mass by applied stress. [L. de-formo, pp. -atus, to deform, fr. forma, form]

deforming
deforming (de-form′ing)

Causing a deviation from the normal form.

deformity
deformity (de-for′mi-te)

A permanent structural deviation from the normal shape, size, or alignment, resulting in disfigurement; may be congenital or acquired. SEE ALSO: deformation (1) .
Åkerlund d. indentation (incisura) with niche of duodenal cap as demonstrated radiographically.
Arnold-Chiari d. [MIM*207950] SYN: Arnold-Chiari malformation.
bell clapper d. a testis and epididymis free of the usual posterior attachment of the tunica vaginalis such that the tunic inserts high on the spermatic cord leaving the gonad more likely to undergo torsion.
boutonnière d. flexion of the proximal interphalangeal joint with hyperextension of the distal interphalangeal joint of the finger, caused by separation of the extensor hood and protrusion of the head of the proximal phalanx through the resulting “buttonhole”; can result from degeneration (rheumatoid arthritis) or trauma.
contracture d. d. of a limb without discernable primary changes of bone.
Erlenmeyer flask d. a d. at the distal end of the femur caused by a failure of the shaft of the bone to develop to its normal tubular shape, with the result that the bone is wide for a much longer distance up the shaft than normal; encountered in Gaucher disease. [resemblance to an E. flask]
gunstock d. a form of cubitus varus resulting from supracondylar or condylar fracture at the elbow in which the axis of the extended forearm is not continuous with that of the arm but is displaced toward midline.
Haglund d. SYN: Haglund disease.
J-sella d. pear-shaped or J-shaped d. of sella turcica caused by increased pressure on growing sphenoid bone; noted in the mucopolysaccharide storage diseases.
keyhole d. mucosal ectropion at the posterior edge of the anus following sphincterotomy at that location.
lobster-claw d. See ectrodactyly.
Madelung d. a distal radioulnar subluxation due to a relative deficiency of axial growth of the medial side of the distal radius, which, as a consequence, is abnormally inclined proximally and ulnarwards. SYN: carpus curvus.
mermaid malformation SYN: sirenomelia.
parachute d. SYN: parachute mitral valve.
reduction d. congenital absence or attenuation of one or more body parts; usually of the limbs or limb components.
silver-fork d. the d. resembling the curve of the back of a fork seen in Colles (distal radius) fracture.
Sprengel d. congenital elevation of the scapula. SYN: scapula elevata.
swan-neck d. hyperextension of the proximal interphalangeal joint with flexion of the distal interphalangeal joint of the finger.
torsional d. in orthopedics, a d. caused by an abnormal rotation of a portion of an extremity with relationship to the long axis of the entire extremity.
whistling d. d. caused by insufficient tissue in the lower border of a repaired cleft lip, giving the appearance of whistling.
Whitehead d. circumferential mucosal ectropion at the anus following Whitehead operation.

defurfuration
defurfuration (de-fer-fer-a′shun)

The shedding of the epidermis in the form of fine scales. SYN: branny desquamation. [L. de, away from, + furfur, bran]

deganglionate
deganglionate (de-gang′gle-on-at)

To deprive of ganglia.

degeneracy
degeneracy (de-jen′er-a-se)

1. A condition marked by deterioration of mental, physical, or moral processes. 2. The fact that several different triplet codons encode the same amino acid. [L. de, from, + genus, (gener-), race]

degenerate
degenerate

1. (de-jen′er-at)To pass to a lower level of mental, physical, or moral state; to fall below the normal or acceptable type or state. 2. (de-jen′e-rat)Below the normal or acceptable; that which has passed to a lower level.

degeneratio
degeneratio (de-jen-er-a′she-o)

SYN: degeneration. [L. degenero, pp. -atus, fr. de, from, + genus, race]

degeneration
degeneration (de-jen-er-a′shun)

1. Deterioration; passing from a higher to a lower level or type. 2. A worsening of mental, physical, or moral qualities. 3. A retrogressive pathologic change in cells or tissues, in consequence of which their functions are often impaired or destroyed; sometimes reversible; in the early stages, necrosis results. SYN: retrograde metamorphosis. SYN: degeneratio. [L. degeneratio]
adipose d. SYN: fatty d..
adiposogenital d. SYN: adiposogenital dystrophy.
age-related macular d. a common macular d. beginning with drusen of the macula and pigment disruption and sometimes leading to severe loss of central vision.
amyloid d. infiltration of amyloid between cells and fibers of tissues and organs. SYN: waxy d. (1) .
angiolithic d. calcareous d. of the walls of the blood vessels.
ascending d. 1. retrograde d. of an injured nerve fiber; i.e., toward the nerve cell of the fiber; 2. spinal cord d. that begins in one region and then progresses cephalad.
atheromatous d. focal accumulation of lipid material (atheroma) in the intima and subintimal portion of arteries, eventually resulting in fibrous thickening or calcification.
axon d. SYN: axonal d..
axonal d. a type of peripheral nerve fiber response to insult, wherein axon death and subsequent breakdown occurs, with secondary breakdown of the myelin sheath associated; caused by focal injury to peripheral nerve fibers; often referred to as wallerian d.. SYN: axon d..
ballooning d. an obsolete term for cells that are infected with certain viruses, resulting in conspicuous swelling of the cell and cytoplasmic vacuolation.
basophilic d. blue staining of connective tissues when hematoxylin-eosin stain is used; found in such conditions as solar elastosis.
calcareous d. in a precise sense, not a degenerative process per se, but the deposition of insoluble calcium salts in tissue that has degenerated and become necrotic, as in dystrophic calcification.
carneous d. SYN: red d..
caseous d. SYN: caseous necrosis.
colloid d. a d. similar to mucoid d., in which the material is inspissated.
cone d. SYN: cone dystrophy.
corticobasal d. a rare, progressive disease involving both cerebral cortex and extrapyramidal structures; clinically manifest as disturbances of voluntary movements and rigidity; pathologic characteristics include d. of the cerebral cortex with balloon neurons and d. of the substantia nigra.
Crooke hyaline d. SYN: Crooke hyaline change.
descending d. 1. wallerian d. of an injured nerve fiber; i.e., d. distal to the lesion; 2. d. caudal to the level of a spinal cord lesion.
disciform d. foveal or parafoveal subretinal neovascularization with retinal separation and hemorrhage leading finally to a circular mass of fibrous tissue with marked loss of visual acuity. SYN: disciform macular d..
disciform macular d. SYN: disciform d..
ectatic marginal d. of cornea SYN: pellucid marginal corneal d..
elastoid d. 1. SYN: elastosis (2) . 2. hyaline d. of the elastic tissue of the arterial wall, seen during involution of the uterus.
elastotic d. SYN: elastosis (2) .
familial pseudoinflammatory macular d. [MIM*136900] macular d. that occurs during the fifth decade of life, with sudden development of a central scotoma in one eye followed rapidly by a similar lesion in the opposite eye; autosomal dominant inheritance. SYN: Sorsby macular d..
fascicular d. d. restricted to certain fascicles of nerves or muscles.
fatty d. abnormal formation of microscopically visible droplets of fat in the cytoplasm of cells, as a result of injury. SYN: adipose d., steatosis (2) .
fibrinoid d., fibrinous d. a process resulting in poorly defined, deeply acidophilic, homogeneous refractile deposits with some staining reactions that resemble fibrin, occurring in connective tissue, blood vessel walls, and other sites.
fibrous d. not a d. per se, but rather a reparative process; cells and foci of tissue previously affected with degenerative processes, and necrosis, are replaced by cellular fibrous tissue.
granular d. SYN: cloudy swelling.
granulovacuolar d. d. of hippocampal brain cells in elderly persons, characterized by basophilic granules surrounded by a clear zone in hippocampal neurons; occurs more frequently in Alzheimer disease.
gray d. d. of the white substance of the spinal cord, the fibers of which lose their myelin sheaths and become darker in color.
hepatolenticular d. SYN: Wilson disease (1) .
hyaline d. a group of several degenerative processes that affect various cells and tissues, resulting in the formation of rounded masses (“droplets”) or relatively broad bands of substances that are homogeneous, translucent, refractile, and moderately to deeply acidophilic; may occur in the collagen of old fibrous tissue, smooth muscle of arterioles or the uterus, and as droplets in parenchymal cells.
hyaloideoretinal d. [MIM*143200] progressive liquefaction and destruction of the vitreous humor with grayish-white preretinal membranes, myopia, cataract, retinal detachment, and hyper- and hypopigmentation; autosomal dominant inheritance. SYN: Wagner disease, Wagner syndrome.
hydropic d. SYN: cloudy swelling.
infantile neuronal d. degenerative disorder of infants with widespread neuronal loss in thalamus, cerebellum, pons, and spinal cord, resembling infantile muscular atrophy.
liquefaction d. 1. necrosis with softening, as in ischemic brain tissue; 2. dissolution of the basal epidermal layer by necrosis of scattered cells with vacuolization, observed in lichen planus, lupus erythematosus, and other dermatologic conditions.
macular d. any ocular d. affecting predominately the posterior fundus, but most commonly age-related macular d..
Mönckeberg d. SYN: Mönckeberg arteriosclerosis.
mucinoid d. a term including both mucoid and colloid d., the essential cellular changes in both being similar, the only difference being that, in colloid d., the substance is firmer and more inspissated than in mucoid d., in which it is thin and jellylike.
mucoid d. a conversion of any of the connective tissues into a gelatinous or mucoid substance. SYN: myxoid d., myxomatous d., myxomatosis (1) .
mucoid medial d. SYN: cystic medial necrosis.
myelinic d. formation of myelin figures in the cytoplasm of cells, possibly by degradation or hydration of lipoprotein of self-digested organelles.
myopic d. association of crescent of the optic disk, atrophy of the choroid and macular pigment, subretinal neovascularization, hemorrhage, and pigment proliferation in pathologic myopia.
myxoid d., myxomatous d. SYN: mucoid d..
neurofibrillary d. formation of coarse, argentophilic, intracytoplasmic fibers, often in complex tangles within intracranial nerve cells. SEE ALSO: Alzheimer disease.
Nissl d. d. of the cell body occurring after transection of the axon; characterized by dispersion of the granular endoplasmic reticulum, swelling of the soma, and an eccentric position of the nucleus of the cell.
olivopontocerebellar d. SYN: olivopontocerebellar atrophy.
parenchymatous d. SYN: cloudy swelling.
pellucid marginal corneal d. bilateral opacification and vascularization of the periphery of the cornea, progressing to formation of a gutter and ectasia. SYN: ectatic marginal d. of cornea.
primary neuronal d. SYN: Alzheimer disease.
primary pigmentary d. of retina SYN: tapetoretinal d..
primary progressive cerebellar d. a familial ataxic condition related to cerebellar d..
pseudotubular d. obsolete term for a form of d. observed in adrenal glands, especially those of patients with febrile infectious disease; the shrunken, lipid-depleted cells of the zona fasciculata (and sometimes the zona glomerulosa) are arranged in a circular pattern about spaces that may be empty or partly filled with fibrin, necrotic cells, or amorphous material.
red d. obsolete term for necrosis, with staining by hemoglobin, which may occur in uterine myomas, especially during pregnancy; marked by softening and a red color resembling partly cooked meat. SYN: carneous d..
reticular d. severe epidermal edema resulting in multilocular bullae.
retrograde d. retrograde cell d. with chromatolysis of Nissl bodies and peripheral displacement of the nucleus of the cell of origin of a nerve fiber injured or sectioned.
Salzmann nodular corneal d. large and prominent nodules of a solid, opaque material that stands out from the surface of the cornea; occurs occasionally in persons previously affected by phlyctenular keratitis.
senile d. the process of involution occurring in old age.
snail track d. circumferential line of fine white dots in the peripheral retina associated with atrophic retinal holes.
Sorsby macular d. SYN: familial pseudoinflammatory macular d..
spheroidal d. SYN: climatic keratopathy.
spongy d. of infancy SYN: Canavan disease.
subacute combined d. of the spinal cord a subacute or chronic disorder of the spinal cord, such as that occurring in certain patients with vitamin B₁₂ deficiency, characterized by a slight to moderate degree of gliosis in association with spongiform d. of the posterior and lateral columns. SYN: combined sclerosis, combined system disease, funicular myelitis (2) , Putnam-Dana syndrome, vitamin B₁₂ neuropathy.
tapetoretinal d. [MIM*272600] a hereditary disorder of the retina mainly affecting photoreceptors and retinal pigment epithelium; this may be a manifestation of Friedreich ataxia, Refsum disease, and abetalipoproteinemia. SYN: primary pigmentary d. of retina.
Terrien marginal d. a form of pellucid marginal corneal d..
transsynaptic d. an atrophy of nerve cells following damage to the axons that make synaptic connection with them; noted especially in the lateral geniculate body. SYN: transneuronal atrophy, transsynaptic chromatolysis.
Türck d. d. of a nerve fiber and its sheath distal to the point of injury or section of the axon; usually applied to d. within the central nervous system.
vacuolar d. formation of nonlipid vacuoles in cytoplasm, most frequently due to accumulation of water by cloudy swelling.
vitelliform d. [MIM*153700] SYN: Best disease. SYN: vitelliruptive d..
vitelliruptive d. SYN: vitelliform d..
wallerian d. the degenerative changes the distal segment of a peripheral nerve fiber (axon and myelin) undergoes when its continuity with its cell body is interrupted by a focal lesion.
waxy d. 1. SYN: amyloid d.. 2. SYN: Zenker d..
xerotic d. scarring of the conjunctiva associated with keratinized epithelium.
Zenker d. obsolete term for a form of severe hyaline d. or necrosis in skeletal muscle, occurring in severe infections. SYN: waxy d. (2) .

degenerative
degenerative (de-jen′er-a-tiv)

Relating to degeneration.

degloving
degloving (de-glov′ing)

1. Intraoral surgical exposure of the anterior mandible used in various orthognathic surgical operations such as genioplasty or mandibular alveolar surgery. 2. Intraoral exposure of the midfacial skeleton used in various operations on the nose and paranasal sinuses particularly for excision of neoplasms. 3. See d. injury.

deglut.
deglut.

Abbreviation for L. deglutiatur, swallow.

deglutition
deglutition (de-gloo-tish′un)

The act of swallowing. [L. de-glutio, to swallow]

deglutitive
deglutitive (de-gloo′ti-tiv)

Relating to deglutition.

Degos
Degos

Robert, French dermatologist, *1904. See D. disease, D. syndrome, Kohlmeier-D. syndrome.

degradation
degradation (deg-ra-da′shun)

The change of a chemical compound into a less complex compound. [L. degradatus, degrade]

degranulation
degranulation (de-gran-u-la′shun)

Disappearance or loss of cytoplasmic granules (lysosomes) from a cell.

degree
degree (de-gre′)

1. One of the divisions on the scale of a measuring instrument such as a thermometer, barometer, etc. See Comparative Temperature Scales appendix. See scale. 2. The 360th part of the circumference of a circle. 3. A position or rank within a graded series. 4. A measure of damage to tissue. [Fr. degré; L. gradus, a step]
degrees of freedom in statistics, the number of independent comparisons that can be made between the members of a sample ( e.g., subjects, test items and scores, trials, conditions); in a contingency table it is one less than the number of row categories multiplied by one less than the number of column categories.

degustation
degustation (de-gus-ta′shun)

1. The act of tasting. 2. The sense of taste. [L. degustatio, fr. de-gusto, pp. -atus, to taste]

dehalogenase
dehalogenase (de-hal′o-jen-as)

Any enzyme (EC subclass 3.8) removing halogen atoms from organic halides.

Dehio
Dehio

Karl K., Russian physician, 1851–1927. See D. test.

dehiscence
dehiscence (de-his′ens)

A bursting open, splitting, or gaping along natural or sutured lines. [L. dehisco, to split apart or open]
iris d. a defect of the eye characterized by multiple holes in the iris.
root d. a loss of the buccal or lingual bone overlaying the root portion of a tooth, leaving that area covered by soft tissue only.
wound d. disruption of apposed surfaces of a wound.

dehumanization
dehumanization (de-hu′man-i-za′shun)

Loss of human characteristics; brutalization by either mental or physical means; stripping one of self-esteem. [de- + humanus, human, fr. homo, man]

dehydrase
dehydrase (de-hi′dras)

Former name for dehydratase.

dehydratase
dehydratase (de-hi′dra-tas)

A subclass (EC 4.2.1.x) of lyases (hydro-lyases) that remove H and OH as H₂O from a substrate, leaving a double bond, or add a group to a double bond by the elimination of water from two substances to form a third; synthase is sometimes used when the synthetic aspect of the reaction is emphasized. Some trivial names of enzymes in this subclass bear the generic term hydratase, emphasizing the reverse reaction.

dehydrate
dehydrate (de-hi′drat)

1. To extract water from. 2. To lose water. [L. de, from + G. hydor (hydr-), water]

dehydration
dehydration (de-hi-dra′shun)

1. Deprivation of water. SYN: anhydration. 2. Reduction of water content. 3. SYN: exsiccation (2) . 4. SYN: desiccation.
absolute d. actual water deficit as measured by a difference from the normal or from a given water content.
relative d. water deficit relative to content of solutes contributing effective osmotic pressure; a state of increased effective osmotic pressure of body fluids.
voluntary d. that physiologic lag or deficit that results when sensations of thirst are not strong enough to bring about complete replacement of water loss, as in rapid sweating.

dehydro- dehydro-

Prefix used in the names of those chemical compounds that differ from other and more familiar compounds in the absence of two hydrogen atoms; e.g., dehydroascorbic acid, which resembles ascorbic acid in all structural features except for its lack of two hydrogen atoms that are present in the ascorbic acid molecule. In systematic nomenclature, didehydro- is preferred as being more exact.

dehydroacetic acid
dehydroacetic acid (de-hi′dro-a-se′tik)

An antimicrobial agent used as a preservative in cosmetics.

dehydrobilirubin
dehydrobilirubin (de-hi′dro-bil-e-roo′bin)

SYN: biliverdin.

dehydrocholate
dehydrocholate (de-hi-dro-ko′lat)

A salt or ester of dehydrocholic acid.

7-dehydrocholesterol
7-dehydrocholesterol (de-hi′dro-ko-les′ter-ol)

A zoosterol in skin and other animal tissues that upon activation by ultraviolet light becomes antirachitic and is then referred to as cholecalciferol (vitamin D₃). SYN: provitamin D₃.

24-dehydrocholesterol
24-dehydrocholesterol

SYN: desmosterol.

dehydrocholic acid
dehydrocholic acid (de-hi-dro-kol′ik)

Has a stimulating effect upon the secretion of bile by the liver (choleretic), and improves the absorption of essential food materials in states associated with deficient bile formation.

11-dehydrocorticosterone
11-dehydrocorticosterone (de-hi′dro-kor-ti-ko-s′ter-on)

Principally, a metabolite of corticosterone, found in the adrenal cortex.

dehydroemetine
dehydroemetine (de-hi-dro-em′e-ten)

A synthetic derivative of emetine; used in the treatment of intestinal amebiasis.
d. resinate a derivative of emetine.

dehydroepiandrosterone
dehydroepiandrosterone

Steroid agent related to male hormones that have been advocated as able to prevent physiologic consequences of aging, without studies that show benefit or safety.

dehydro-3-epiandrosterone dehydro-3-epiandrosterone (DHEA) (de-hi′dro-ep-e-an-dros′ter-on)

a steroid secreted chiefly by the adrenal cortex, but also by the testis; it is the principal precursor of urinary 17-ketosteroids. Weakly androgenic itself, it is metabolized to delta-5 androstenediol, a hormone with both androgenic and estrogenic effects, and is one of the precursors of testosterone. Serum levels are elevated in adrenal virilism. It may function as a neurotransmitter. SYN: androstenolone, dehydroisoandrosterone.DHEA secretion begins during fetal life, reaches a peak in the 3rd decade, and declines steadily thereafter; the level at age 80 is only 10–20% of the peak level. This decline has been speculatively associated with the changes of aging. Commercial formulations of DHEA are marketed as dietary supplements, although this substance is neither a nutrient nor a component of the human food chain. Available from health food stores in 10-, 25-, and 50-mg capsules, DHEA has been promoted for the prevention of degenerative diseases including atherosclerosis, Alzheimer dementia, and parkinsonism, and other effects of aging. None of the alleged benefits have been demonstrated in large, randomized clinical trials. Long-term administration to postmenopausal women has been associated with insulin resistance, hypertension, and reduction of LDL cholesterol. An analysis of 16 preparations of DHEA by high-performance liquid chromatography showed a variation in content from 0–150% of the labeled strength; only 7 products fell between the expected 90–110% of labeled strength.

dehydrogenase
dehydrogenase (de-hi′dro-jen-as)

Class name for those enzymes that oxidize substrates by catalyzing removal of hydrogen from metabolites (hydrogen donors) and transferring it to other substances (hydrogen acceptors), which are thus reduced; most of the oxidative enzymes (oxidoreductases, EC class 1) perform their oxidations in this manner.
aerobic d. an enzyme (usually a metalloflavoenzyme) catalyzing the transfer of hydrogen from some metabolite to oxygen, forming hydrogen peroxide in the process; e.g., xanthine oxidase and others in several sub-subclasses ( e.g., EC 1.1.3, 1.2.3, 1.7.3, 1.8.3, 1.10.3).
anaerobic d. an enzyme (usually a pyridinoenzyme) catalyzing the transfer of hydrogen from some metabolite to some acceptor molecule ( e.g., NAD⁺, cytochrome) other than oxygen; e.g., lactate dehydrogenases, isocitrate dehydrogenases, and others in EC class 1, excluding those listed under aerobic d..
α-keto acid d. See α-keto acid d..
Robison ester d. SYN: glucose-6-phosphate d..

dehydrogenate
dehydrogenate (de-hi′dro-jen-at)

To subject to dehydrogenation.

dehydrogenation
dehydrogenation (de-hi′dro-jen-a′shun)

Removal of a pair of hydrogen atoms from a compound by the action of enzymes (dehydrogenases) or other catalysts.

dehydroisoandrosterone
dehydroisoandrosterone (de-hi′dro-i-so-an-dros′ter-on)

SYN: dehydro-3-epiandrosterone.

dehydroretinaldehyde
dehydroretinaldehyde (de-hi′dro-ret-i-nal′de-hid)

Dehydroretinol with –CHO instead of –CH₂OH at the terminal carbon of the side chain. SYN: retinene-2, vitamin A₂ aldehyde.

dehydroretinoic acid
dehydroretinoic acid (de-hi′dro-ret-i-no′ik)

Dehydroretinol with –COOH in place of –CH₂OH at the terminal carbon of the side chain.

dehydroretinol
dehydroretinol (de-hi-dro-ret′i-nol)

Retinol with an additional double bond in the 3-4 position of the cyclohexane ring. SYN: vitamin A₂.

dehydrosugars
dehydrosugars (de-hi′dro-shug-erz)

SYN: anhydrosugars.

dehypnotize
dehypnotize (de-hip′no-tiz)

To bring out of the hypnotic state.

deiminases
deiminases (de-im′i-nas-ez)

SYN: iminohydrolases.

deinstitutionalization
deinstitutionalization (de′in-sti-too′shun-al-i-za-shun)

The discharge of institutionalized patients from a mental hospital into treatment programs in half-way houses and other community-based programs.

deionization
deionization (de-i′-on-i-za′shun)

The production of a mineral-free state by the removal of ions.

Deiters
Deiters

Otto F.K., German anatomist, 1834–1863. See D. cells, under cell, D. terminal frames, under frame, D. nucleus.

déjà voulu
déjà voulu (da-zha′ voo-loo′)

A term for a type of disturbance of memory in which the individual believes that his or her present desires are exactly the same as the desires the individual had some time before.

déjà vu
déjà vu (da-zhah-voo′)

Feeling of having been in a place before. See d. phenomenon. See phenomenon. [Fr. already seen]

dejecta
dejecta (de-jek′ta)

SYN: dejection (3) . [L. neut, pl. of de-jectus, fr. de-jicio, to cast down]

dejection
dejection (de-jek′shun)

1. SYN: depression (4) . 2. The discharge of excrementitious matter. 3. The matter so discharged. SYN: dejecta. [L. dejectio, fr. de- jicio, pp. -jectus, to cast down]

Dejerine
Dejerine

Joseph J., Paris neurologist, 1849–1917. See D. disease, D. hand phenomenon, D. reflex, D. sign, D.-Roussy syndrome, D.-Sottas disease, D.-Klumpke syndrome, Landouzy-D. dystrophy.

Dejerine-Klumpke
Dejerine-Klumpke

Augusta, French neurologist (born in the U.S.), 1859–1927. See Klumpke palsy, Klumpke paralysis, D. palsy, D. syndrome.

deka- deka-

See deca-.

Delafield
Delafield

Francis, U.S. physician and pathologist, 1841–1915. See D. hematoxylin.

delamination
delamination (de-lam-i-na′shun)

Division into separate layers. [L. de, from, + lamina, a thin plate]

Delaney clause
Delaney clause

A clause of the Food Additive Amendment of the U.S. Federal law specifying that no substance that has been found to induce cancer in any animal may be incorporated into food. [James F. Delaney, U.S. Congressman]

de Lange
de Lange

Cornelia, Dutch pediatrician, 1871–1950. See de Lange syndrome.

Delbet
Delbet

Pierre L.E., French surgeon, 1861–1925. See D. sign.

Del Castillo
Del Castillo

E.B., 20th century Argentinian physician. See D. syndrome.

de-lead
de-lead (de-led′)

To cause the mobilization and excretion of lead deposited in the bones and other tissues, as by the administration of a chelating agent.

deleterious
deleterious (del-e-ter′e-us)

Injurious; noxious; harmful. [G. deleterios, fr. deleomai, to injure]

deletion
deletion (de-le′shun)

In genetics, any spontaneous elimination of part of the normal genetic complement, whether cytogenetically visible (chromosomal d.) or found by molecular techniques. [L. deletio, destruction]
chromosomal d. a microscopically evident loss of part of a chromosome. SEE ALSO: monosomy.
gene d. d. of a segment of a chromosome too small to be detected cytogenetically, inferred from the phenotype at one particular locus.
interstitial d. d. that does not involve the terminal parts of a chromosome.
nucleotide d. d. of a single nucleotide, which in a transcribed gene will lead to a frame-shift mutation. SYN: point d. (2) .
point d. 1. d. involving a submicroscopic loss of genetic material too small to be resolved by linkage analysis; 2. SYN: nucleotide d..
terminal d. d. involving the terminal part of a chromosome and leading to a adhesive terminus.

delicate
delicate (del′i-kat)

Of feeble resisting power. [L. delicatus, soft, luxurious, fr. de, from, + lacio, to entice]

delimitation
delimitation (de-lim-i-ta′shun)

Marking off; putting bounds or limits; preventing the spread of a morbid process in the body or of a disease in the community. [L. de-limito, pp. -atus, to bound, fr. limes, boundary]

deliquesce
deliquesce (del-i-kwes′)

To undergo deliquescence.

deliquescence
deliquescence (del-i-kwes′ens)

Becoming damp or liquid by absorption of water from the atmosphere and then dissolving in the water taken up; a property found in certain salts, such as CaCl₂. [L. de-liquesco, to melt or become liquid]

deliquescent
deliquescent (del-i-kwes′ent)

Denoting a solid capable of deliquescence.

deliria
deliria (de-lir′e-a)

Plural of delirium. See delirium.

delirious
delirious (de-lir′e-us)

In a state of delirium.

delirium
delirium, pl .deliria (de-lir′e-um, de-lir′e-a)

An altered state of consciousness, consisting of confusion, distractibility, disorientation, disordered thinking and memory, defective perception (illusions and hallucinations), prominent hyperactivity, agitation and autonomic nervous system overactivity; caused by a number of toxic, structural, and metabolic disorders. [L. fr. deliro, to be crazy, fr. de- + lira, a furrow (i.e., go out of the furrow)]
acute d. d. of recent, rapid onset.
alcohol withdrawal d. the d. experienced by an alcohol-habituated individual caused by the abrupt cessation of alcohol intake.
anxious d. d. in which the predominating symptom is an incoherent apprehension or anxiety.
d. cordis obsolete term for atrial fibrillation.
posttraumatic d. d. caused by a structural traumatic brain injury.
senile d. d. associated with senile dementia.
toxic d. d. caused by the action of a poison.
d. tremens (DT) a severe, sometimes fatal, form of d. due to alcoholic withdrawal following a period of sustained intoxication. [L. pres. p. of tremo, to tremble]

delitescence
delitescence (del-i-tes′ens)

Rarely used term for: 1. Sudden subsidence of symptoms; disappearance of a tumor or a cutaneous lesion. 2. Period of incubation of an infectious disease. [L. delitesco, to lie hidden away]

deliver
deliver (de-liv′er)

1. To assist a woman in childbirth. 2. To extract from an enclosed place, as the fetus from the womb, an object or foreign body, e.g., a tumor from its capsule or surroundings, or the lens of the eye in cases of cataract. [fr. O. Fr. fr. L. de- + liber, free]

delivery
delivery (de-liv′er-e)

Passage of the fetus and the placenta from the genital canal into the external world.
assisted cephalic d. extraction of a fetus that presents by the head.
breech d. extraction or expulsion of a fetus that presents by the buttocks or feet.
forceps d. assisted birth of the child by an instrument designed to grasp the fetal head.
high forceps d. d. by forceps applied to the fetal head before engagement has taken place.
low forceps d. d. by forceps applied to the fetal head at station ≥ +2 cm and not on the pelvic floor. This classification of forceps d. may be with or without rotation of the fetal head.
midforceps d. d. by forceps applied to the fetal head at above +2 station, but after engagement has taken place.
outlet forceps d. d. by forceps applied to the fetal head when it has reached the perineal floor and is visible between contractions.
perimortem d. SYN: postmortem d..
postmortem d. extraction of the fetus after the death of its mother. SYN: perimortem d..
premature d. birth of a fetus between 20 and 37 weeks' gestation. SEE ALSO: premature birth.
spontaneous cephalic d. unassisted expulsion of a fetus that presents by the head.

delle
delle (del′eh)

The central lighter-colored portion of the erythrocyte, as observed in a stained film of blood. [Ger. D., low ground, pit]

dellen
dellen

Shallow, saucerlike, clearly defined excavations at the margin of the cornea, about 1.5 by 2 mm, due to localized dehydration; also called Fuchs d.. [Ger. pl. of Delle, low ground, pit]

delomorphous
delomorphous (del-o-mor′fus)

Of definite form and shape; a term applied in the past to the parietal cells of the gastric glands. [G. delos, manifest, + morphe, form]

delouse
delouse (de-lows′)

To remove lice from; to free from infestation with lice; used especially of prophylaxis of louse-borne diseases.

delphinine
delphinine (del′fin-en)

A toxic alkaloid, an aconine derivative, from Delphinium staphisagria; it resembles aconitine in its action and chemical structure.

Delphinium ajacis
Delphinium ajacis (del-fin′e-um a-ja′sis)

A species of plant (family Ranuculaceae) containing the alkaloids ajacine and ajaconine; the dried ripe seeds have been used externally as a parasiticide in pediculosis; rarely used now because of its toxicity. SYN: larkspur. [G. delphinion, larkspur]

delta
delta (Δ) (del′ta)

1. Fourth letter of the Greek alphabet, &D.; (capital), &d.; (lower case). 2. In anatomy, a triangular surface.
d. check a comparison of consecutive values for a given test in a patient's laboratory file used to detect abrupt changes, usually generated as a part of computer-based quality control programs. SYN: &D.; check.
d. fornicis SYN: commissura fornicis.
Galton d. 1. a more or less well-marked triangle, in a fingerprint, on either side where the straight ridges near the joint of the distal phalanx are succeeded by arches, loops, or whorls; SEE ALSO: Galton system of classification of fingerprints, under fingerprint. 2. SYN: triradius.
d. mesoscapulae the flat triangular surface at the vertebral extremity of the spine of the scapula over which glides the tendon for the lower fibers of the trapezius muscle.

deltoid
deltoid (del′toyd)

Resembling the Greek letter delta (Δ); triangular. [G. deltoeides, shaped like the letter delta]

delusion
delusion (de-loo′zhun)

A false belief or wrong judgment held with conviction despite incontrovertible evidence to the contrary. [L. de-ludo, pp. -lusus, to play false, deceive, fr. ludo, to play]
d. of control, d. of being controlled a d. in which one experiences one's feelings, impulses, thoughts, or actions as not one's own, but as being imposed on by some external force. SYN: d. of passivity.
encapsulated d. a d. that usually relates to one specific topic or belief but does not pervade an individual's life or level of functioning.
expansive d. SYN: d. of grandeur.
d. of grandeur a d. in which one believes oneself possessed of great wealth, intellect, importance, power, etc. SYN: expansive d., grandiose d..
grandiose d. SYN: d. of grandeur.
d. of negation a d. in which one imagines that the world and all that relates to it have ceased to exist. SYN: nihilistic d..
nihilistic d. SYN: d. of negation.
organic delusions false beliefs experienced in the delirium associated with dementia in conjunction with traumatic injury to the brain, or an organic change in the brain such as in Alzheimer syndrome, or in cocaine or other drug intoxication.
d. of passivity SYN: d. of control.
d. of persecution, persecutory d. a false notion that one is being persecuted; characteristic symptom of paranoid schizophrenia.
d. of reference a delusional idea that external events, etc., refer to the self.
somatic d. a d. having reference to a nonexistent lesion or alteration of some organ or part of the body; sometimes indistinguishable from hypochondriasis.
systematized d. a d. that is logically constructed from a false premise and embraces a specific sector of the patient's life.
unsystematized d. one of a group of apparently discrete, disconnected delusions.

delusional
delusional (de-loo′zhun-al)

Relating to a delusion.

demand
demand (de-mand′)

A quantity of a substance, commodity, or service wanted or required.
biochemical oxygen d. (BOD) the rate at which dissolved oxygen is consumed by an organism (often, a microorganism) or a culture of cells.

demarcation
demarcation (de-mar-ka′shun)

A setting of limits; a boundary. [Fr. fr. L. de, from, + Mediev. L. marco, to mark]

Demarquay
Demarquay

Jean N., French surgeon, 1814–1875. See D. sign.

demasculinizing
demasculinizing (de-mas′ku-lin-iz′ing)

Depriving of male characteristics or inhibiting development of such characteristics.

Dematiaceae
Dematiaceae (de-mat-e-a′se-e)

A family of soil-inhabiting, brown or black melanin-producing fungi found in decaying vegetables, rotting wood, and forest carpets, and including several of the dark-colored genera that cause chromoblastomycosis in humans, such as Exophiala, Phialophora, Fonsecaea, and Cladosporium.

dematiaceous
dematiaceous (de-mat-e-a′shus)

Denoting dark conidia and/or hyphae, usually brown or black; used frequently to denote dark-colored fungi.

deme
deme (dem)

A local, small, highly inbred group or kinship. Cf.:isolate. [G. demos, people]

demecarium bromide
demecarium bromide (dem-e-kar′e-um)

A potent cholinesterase inhibitor used in the treatment of glaucoma and accommodative esotropia; it is stable in aqueous solution.

demeclocycline
demeclocycline (dem′e-klo-si′klen)

A broad-spectrum antibiotic that is more slowly excreted and more stable in acid and alkali than are other forms of the tetracyclines; available as the hydrochloride.

demecolcine
demecolcine (dem-e-kol′sen)

An alkaloid from Colchicum autumnale (family Liliaceae) similar chemically to colchicine except that the acetyl group is replaced by a methyl group; used for gout and leukemia, is said to be less toxic than colchicine, and has an action upon mitosis similar to that of colchicine.

demented
demented (de-ment′ed)

Suffering from dementia.

dementia
dementia (de-men′she-a)

The loss, usually progressive, of cognitive and intellectual functions, without impairment of perception or consciousness; caused by a variety of disorders including severe infections and toxins, but most commonly associated with structural brain disease. Characterized by disorientation, impaired memory, judgment, and intellect, and a shallow labile affect. SYN: amentia (2) . [L. fr. de- priv. + mens, mind]
AIDS d. SYN: AIDS d. complex.
Alzheimer d. SYN: Alzheimer disease.
catatonic d. d. with catatonic symptoms.
dialysis d. SYN: dialysis encephalopathy syndrome.
epileptic d. d. occurring in an individual afflicted with epilepsy, and thought to be a result of prolonged seizures, the epileptogenic brain lesion, or antiepileptic drugs.
hebephrenic d. d. with hebephrenic symptoms.
Lewy body d. SYN: diffuse Lewy body disease.
multi-infarct d. SYN: vascular d..
paralytic d. d. and paralysis resulting from a chronic syphilitic meningoencephalitis. SYN: d. paralytica.
d. paralytica SYN: paralytic d..
posttraumatic d. d. caused by traumatic brain injury.
d. praecox any one of the group of psychotic disorders known as the schizophrenias; formerly used to describe schizophrenia as a single entity. [L. precocious]
presenile d., d. presenilis 1. d. of Alzheimer disease developing before age 65; 2. SYN: Alzheimer disease.
primary d. d. occurring independently as a mental disorder.
primary senile d. SYN: Alzheimer disease.
secondary d. chronic d. following and due to a psychosis or some other underlying disease process.
senile d. d. of Alzheimer disease developing after age 65.
toxic d. d. caused by an exogenous agent.
vascular d. a steplike deterioration in intellectual functions with focal neurologic signs, as the result of multiple infarctions of the cerebral hemispheres. SYN: multi-infarct d..

demethylase
demethylase (de-meth′i-las)

SYN: methyltransferase.

demethylation
demethylation

The enzymatic removal of methyl groups.

demi- demi-

Half, lesser. SEE ALSO: hemi-, semi-. [Fr. fr. L. dimidius, half]

demigauntlet
demigauntlet (dem-e-gawnt′let)

A glovelike bandage for the fingers and hand. [demi- + gauntlet, armored glove, fr. M.E., fr. O.Fr., fr. Germanic]

demilune
demilune (dem′e-loon)

1. A small body with a form similar to that of a half-moon or a crescent. 2. Term frequently used for the gametocyte of Plasmodium falciparum. [Fr. half-moon]
Giannuzzi demilunes SYN: serous demilunes.
Heidenhain demilunes SYN: serous demilunes.
serous demilunes the serous cells at the distal end of a mucous, tubuloalveolar secretory unit of certain salivary glands. SYN: Giannuzzi crescents, Giannuzzi demilunes, Heidenhain crescents, Heidenhain demilunes.

demineralization
demineralization (de-min′er-al-i-za′shun)

A loss or decrease of the mineral constituents of the body or individual tissues, especially of bone.

demipenniform
demipenniform (dem′e-pen′i-form)

SYN: semipennate.

Demodex
Demodex (dem′o-deks)

A genus of very minute (0.1–0.4 mm) follicular mites (family Demodicidae) that inhabit the skin and are usually found in the sebaceous glands and hair follicles of mammals, including humans. Some cases of blepharitis in humans have been attributed to D. infection; use of facial creams promotes D. infection in older women, resulting in facial erythema with follicular scaling. [G. demos, tallow, + dex, a woodworm]
D. folliculorum a very common, universally distributed, and usually nonpathogenic species of mite that inhabits the hair follicles and sebaceous glands of humans, commonly of the face around the nose and scalp margins. SYN: Acarus folliculorum.

demography
demography (de-mog′ra-fe)

The study of populations, especially with reference to size, density, fertility, mortality, growth rate, age distribution, migration, and vital statistics. [G. demos, people, + grapho, to write]
dynamic d. a study of the functioning of a community, including statistical records.

Demoivre
Demoivre

Abraham, English mathematician, 1667–1754. See D. formula.

demoniac
demoniac (de-mo′ne-ak)

Frenzied, fiendish, as if possessed by evil spirits. [G. daimon, a spirit]

demonstrator
demonstrator (dem′on-stra-ter, -tor)

An assistant to a professor of anatomy, surgery, etc., who prepares for the lecture by dissections or collection of patients, or who instructs small classes supplementary to the regular lectures; a d. corresponds in a general way to the Dozent of a German university. [L. de-monstro, pp. -atus, to point out]

De Morgan
De Morgan

Campbell, English physician, 1811–1876. See D. spots, under spot.

demorphinization
demorphinization (de-mor′fin-i-za′shun)

1. Removal of morphine from an opiate. 2. Gradual withdrawal of morphine as a method of overcoming morphine dependence.

de Morsier
de Morsier

Georges, 20th century Swiss neurologist. See de Morsier syndrome.

demucosation
demucosation (de-mu-ko-sa′shun)

Rarely used term for excision or stripping of the mucosa of any part.

demulcent
demulcent (de-mul′sent)

1. Soothing; relieving irritation. 2. An agent, such as a mucilage or oil, that soothes and relieves irritation, especially of the mucous surfaces. [L. de-mulceo, pp. -mulctus, to stroke lightly, to soften]

de Musset
de Musset

Alfred. See Musset.

demyelination
demyelination, demyelinization (de-mi′e-li-na′shun, de-mi′e-lin-i-za′shun)

Loss of myelin with preservation of the axons or fiber tracts. Central d. occurs within the central nervous system ( e.g., the d. seen with multiple sclerosis); peripheral d. affects the peripheral nervous system ( e.g., the d. seen with Guillain-Barré syndrome).

denarcotize
denarcotize (de-nar′ko-tiz)

To remove narcotic properties from an opiate; to deprive of narcotic properties.

denatonium benzoate
denatonium benzoate (de-na-to′ne-um)

An alcohol denaturant.

denaturation
denaturation (de-na-tu-ra′shun)

The process of becoming denatured.

denatured
denatured (de-na′turd)

1. Made unnatural or changed from the normal in any of its characteristics; often applied to proteins or nucleic acids heated or otherwise treated to the point where tertiary structural characteristics are altered. 2. Adulterated, as by addition of methanol to ethanol.

dendriform
dendriform (den′dri-form)

Tree-shaped, or branching. SYN: arborescent, dendritic (1) , dendroid. [G. dendron, tree, + L. forma, form]

dendrite
dendrite (den′drit)

1. One of the two types of branching protoplasmic processes of the nerve cell (the other being the axon). SYN: dendritic process, dendron, neurodendrite, neurodendron. 2. A crystalline treelike structure formed during the freezing of an alloy. [G. dendrites, relating to a tree]
apical d. SYN: apical process.

dendritic
dendritic (den-drit′ik)

1. SYN: dendriform. 2. Relating to the dendrites of nerve cells.

dendrogram
dendrogram (den′dro-gram)

A treelike figure used to represent graphically a hierarchy. [dendron, tree, + gramma, a drawing]

dendroid
dendroid (den′droyd)

SYN: dendriform. [G. dendron, tree, + eidos, appearance]

dendron
dendron

SYN: dendrite (1) . [G. a tree]

denervate
denervate (de-ner′vat)

To cause denervation.

denervation
denervation (de-ner-va′shun)

Loss of nerve supply.

dengue
dengue (den′ga)

A disease of tropical and subtropical regions that occurs epidemically, is caused by d. virus, a member of the family Flaviviridae. There are 4 antigenic types, and they are transmitted by a mosquito of the genus Aedes (usually A. aegypti, but frequently A. albopictus). Four grades of severity are recognized: grade I, fever and constitutional symptoms; grade II, grade I plus spontaneous bleeding (of skin, gums, or gastrointestinal tract); grade III, grade II plus agitation and circulatory failure; grade IV, profound shock. SYN: Aden fever, bouquet fever, breakbone fever, dandy fever, date fever, d. fever, d. hemorrhagic fever, exanthesis arthrosia, polka fever, scarlatina rheumatica, solar fever (1) . [Sp. corruption of “dandy” fever]
hemorrhagic d. a more severe form of d. characterized by hemorrhagic skin lesions, which has erupted in a number of epidemic outbreaks in the Pacific basin.

denial
denial (de-ni′al)

An unconscious defense mechanism used to allay anxiety by denying the existence of important conflicts, troublesome impulses, events, actions, or illness. SYN: negation. [M.E., fr, O.Fr., fr. L. denegare, to say no]

denidation
denidation (den-i-da′shun)

Exfoliation of the superficial portion of the mucous membrane of the uterus; stripping off of the menstrual decidua. [L. de, from, + nidus, nest]

denitration
denitration (de-ni-tra′shun)

SYN: denitrification.

denitrification
denitrification (de-ni′tri-fi-ka′shun)

1. Removal of nitrogen from any material or chemical compound; especially from the soil, as by certain (denitrifying) bacteria that render the nitrogen unavailable for plant growth. 2. Withdrawal of nitrogen from soil by plant growth. SYN: denitration.

denitrify
denitrify (de-ni′tri-fi)

To remove nitrogen from any material or chemical compound.

denitrogenation
denitrogenation (de-ni′tro-je-na′shun)

Elimination of nitrogen from lungs and body tissues by breathing gases devoid of nitrogen.

Dennie
Dennie

Charles Clayton, U.S. dermatologist, 1883–1971. See D.-Morgan fold, D. line.

denominator
denominator (de-nom′i-na-tor)

The lower portion of a fraction used to calculate a rate or ratio; the population at risk in the calculation of a rate or ratio.

Denonvilliers
Denonvilliers

Charles P., French surgeon, 1808–1872. See D. aponeurosis, D. ligament.

de novo
de novo (di-no′vo)

Anew; often applied to particular biochemical pathways in which metabolites are newly biosynthesized ( e.g., d. purine biosynthesis). [L.]

dens
dens, pl .dentes (denz, den′tez) [TA]

1. SYN: tooth. 2. A strong toothlike process projecting upward from the body of the axis, or epistropheus, around which the atlas rotates. SYN: d. axis [TA] , odontoid process of epistropheus, odontoid process. [L.]
dentes acustici [TA] SYN: acoustic teeth.
d. angularis SYN: canine tooth.
d. axis [TA] SYN: d. (2) .
d. bicuspidus, pl .dentes bicuspidi SYN: premolar tooth.
d. caninus, pl .dentes canini [TA] SYN: canine tooth.
d. cuspidatus, pl .dentes cuspidati SYN: canine tooth.
d. deciduus, pl .dentes decidui [TA] SYN: deciduous tooth.
d. in dente a developmental disturbance in tooth formation resulting from invagination of the epithelium associated with crown development into the area destined to become pulp space; after calcification there is an invagination of enamel and dentin into the pulp space, giving the radiographic appearance of a “tooth within a tooth.” SYN: d. invaginatus.
d. incisivus, pl .dentes incisivi [TA] SYN: incisor tooth.
d. invaginatus (denz in′va-ge-na′-tus) SYN: d. in dente. [Mediev. L. folded inward, fr. L. vagina, sheath]
d. lacteus SYN: deciduous tooth.
d. molaris, pl .dentes molares [TA] SYN: molar tooth. SEE ALSO: molar.
d. molaris tertius [TA] SYN: third-year molar tooth.
d. permanens, pl .dentes permanentes [TA] SYN: permanent tooth.
d. premolaris, pl .dentes premolares [TA] SYN: premolar tooth.
d. sapientiae SYN: third-year molar tooth. [L. sapientia, wisdom]
d. serotinus third-year molar tooth.
d. succedaneus SYN: permanent tooth.

densimeter
densimeter (den-sim′e-ter)

SYN: densitometer (1) . [L. densitas, density, + G. metron, measure]

densitometer
densitometer (den-si-tom′e-ter)

1. An instrument for measuring the density of a fluid. SYN: densimeter. 2. An instrument for measuring, by virtue of relative turbidity, the growth of bacteria in broth; useful in microbiologic assay of nutrients and antibiotics, phage studies, etc. 3. An instrument for measuring the density of components ( e.g., protein fractions) separated by electrophoresis or chromatography, utilizing light absorption or reflection. 4. An electronic instrument for measuring the blackening of radiographic film by x-ray exposure; used for film sensitometry, bone densitometry, measurement of line spread function (microdensitometer). 5. An instrument for measuring the extent to which a material absorbs or reflects light. [L. densitas, density, + G. metron, measure]

densitometry
densitometry (den-si-tom′e-tre)

A procedure utilizing a densitometer.

density
density (ρ) (den′si-te)

1. The compactness of a substance; the ratio of mass to unit volume, usually expressed as g/cm³ (kg/m³ in the SI system). 2. The quantity of electricity on a given surface or in a given time per unit of volume. 3. In radiological physics, the opacity to light of an exposed radiographic or photographic film; the darker the film, the greater the measured d.. 4. In clinical radiology, a less exposed area on a film, corresponding to a region of greater x-ray attenuation (radiopacity) in the subject; the more light transmitted by the film, the greater the d. of the subject; this is not actually the opposite of the prior definition, since one concerns film d. and the other subject d.. [L. densitas, fr. densus, thick]
bone d. quantitative measurement of the mineral content of bone, used as an indicator of the structural strength of the bone and as a screen for osteoporosis
buoyant d. the d. that allows a substance to float in some standard fluid.
count d. SYN: photon d..
flux d. 1. SYN: flux (4) . 2. either particle flux d., the particle fluence rate, or energy flux d., the energy fluence rate of intensity. Cf.:fluence.
incidence d. the person-time incidence rate.
optic d. (OD) SYN: absorbance.
photon d. the number of counted events recorded in scintigraphy per square centimeter or per square inch of imaged area. SYN: count d..
spin d. the number of nuclear dipoles per unit volume.
vapor d. the mass per unit volume of a vapor; since the vapor d. changes with temperature and pressure, it is commonly expressed as a specific gravity, i.e., the weight of the vapor divided by the weight of an equal volume of a reference gas ( e.g., oxygen or hydrogen) at the same temperature and pressure.

dent- dent-, denti-, dento-

Teeth; dental. SEE ALSO: odonto-. [L. dens, tooth]

dental
dental (den′tal)

Relating to the teeth. [L. dens, tooth]

dental engine
dental engine

The motive power of a dental handpiece that causes it to rotate.

dentalgia
dentalgia (den-tal′je-a)

SYN: toothache. [L. dens, tooth, + G. algos, pain]

dentate
dentate (den′tat)

Notched; toothed; cogged. [L. dentatus, toothed]

dentatectomy
dentatectomy (den-ta-tek′to-me)

Surgical destruction of the dentate nucleus of the cerebellum. [dentate (nucleus) + G. ectome, excision]

dentatum
dentatum (den-ta′tum, den-tah′tum)

SYN: dentate nucleus of cerebellum. [L. neut. of dentatus, toothed]

dentes
dentes (den′tez)

Plural of dens. [L.]

denti- denti-

See dent-.

dentia
dentia (den-te′a)

The process of tooth development or eruption. Also serves to denote a relationship to the teeth. [dent- + suffix -ia, condition, process]
d. praecox (den-te′a pre-coks) premature tooth eruption. [L. premature]
d. tarda (den-tea′ tar′da) delayed tooth eruption. [L. delayed]

denticle
denticle (den′ti-kl)

1. SYN: endolith. 2. A toothlike projection from a hard surface. [L. denticulus, a small tooth]

denticulate
denticulate, denticulated (den-tik′u-lat, -lat-ed)

1. Finely dentated, notched, or serrated. 2. Having small teeth.

dentiform
dentiform (den′ti-form)

Tooth-shaped; pegged. SEE ALSO: odontoid (1) . [denti- + L. forma, form]

dentifrice
dentifrice (den′ti-fris)

Any preparation used in the cleansing of the teeth, e.g., a tooth powder, toothpaste, or tooth wash. [L. dentifricium, fr. dens, tooth, + frico, pp. frictus, to rub]

dentigerous
dentigerous (den-tij′er-us)

Arising from or associated with teeth, as a d. cyst. [denti- + L. gero, to bear]

dentilabial
dentilabial (den′ti-la′be-al)

Relating to the teeth and lips. [denti- + L. labium, lip]

dentilingual
dentilingual (den-ti-ling′gwal)

Relating to the teeth and tongue. [denti- + L. lingua, tongue]

dentin
dentin (den′tin)

SYN: dentine. [L. dens, tooth]
hereditary opalescent d. 1. SYN: dentinogenesis imperfecta. 2. SYN: opalescent d..
hypersensitive d. exposed d., usually at the cervical portion of a tooth, painful to touch, sweetness, or temperature changes.
interglobular d. imperfectly calcified matrix of d. situated between the calcified globules near the dentinal periphery.
irregular d., irritation d. SYN: tertiary d..
opalescent d. d. usually associated with dentinogenesis imperfecta. It gives an unusual opalescent or translucent appearance to the teeth. SYN: hereditary opalescent d. (2) .
peritubular d. an electron-dense layer of d. observed adjacent to the odontoblastic process.
primary d. d. which forms until the root is completed.
reparative d. SYN: tertiary d..
sclerotic d. d. characterized by calcification of the dentinal tubules as a result of injury or normal aging. SYN: transparent d..
secondary d. d. formed by normal pulp function after root end formation is complete.
tertiary d. morphologically irregular d. formed in response to an irritant. SYN: irregular d., irritation d., reparative d..
transparent d. SYN: sclerotic d..
vascular d. SYN: vasodentin.

dentinal
dentinal (den′ti-nal)

Relating to dentin.

dentinalgia
dentinalgia (den-ti-nal′je-a)

Dentinal sensitivity or pain. [dentin + G. algos, pain]

dentine
dentine (den′ten) [TA]

The ivory forming the mass of the tooth. About 20% is organic matrix, mostly collagen, with some elastin and a small amount of mucopolysaccharide; the inorganic fraction (70%) is mainly hydroxyapatite, with some carbonate, magnesium, and fluoride. The dentinum is traversed by a large number of fine tubules running from the pulp cavity outward; within the tubules are processes from the odontoblasts. SYN: dentinum [TA] , dentin, ebur dentis, substantia eburnea.

dentinocemental
dentinocemental (den′ti-no-se-men′tal)

Relating to the dentin and cementum of teeth. SYN: cementodentinal.

dentinoenamel
dentinoenamel (den′ti-no-e-nam′el)

Relating to the dentin and enamel of teeth. SYN: amelodentinal.

dentinogenesis
dentinogenesis (den′ti-no-jen′e-sis)

The process of dentin formation in the development of teeth. [dentin + G. genesis, production]
d. imperfecta [MIM*125490 & MIM*125500] an autosomal dominant disorder of the teeth characterized clinically by translucent gray to yellow-brown teeth involving both primary and permanent dentition; the enamel fractures easily, leaving exposed dentin, which undergoes rapid attrition; radiographically, the pulp chambers and canals appear obliterated and the roots are short and blunted; sometimes occurs in association with osteogenesis imperfecta; autosomal dominant inheritance. SYN: hereditary opalescent dentin (1) .

dentinoid
dentinoid (den′ti-noyd)

1. Resembling dentin. 2. SYN: dentinoma. [dentin + G. eidos, resembling]

dentinoma
dentinoma (den′ti-no′ma)

A rare benign odontogenic tumor consisting microscopically of dysplastic dentin and strands of epithelium within a fibrous stroma. SYN: dentinoid (2) . [dentin + G. -oma, tumor]

dentinum
dentinum (den′ti-num) [TA]

SYN: dentine. [L. dens, tooth]

dentiparous
dentiparous (den-tip′a-rus)

Tooth-bearing. [denti- + L. pario, to bear]

dentist
dentist

A legally qualified practitioner of dentistry.

dentistry
dentistry (den′tis-tre)

The healing science and art concerned with the structure and function of the oral-facial complex, and with the prevention, diagnosis, and treatment of deformities, pathoses, and traumatic injuries thereof. SYN: odontology, odontonosology.
community d. public health d., with an academic base, emphasizing the professional obligation to foster the delivery of prevention, education, and care to populations.
esthetic d. a field of d. concerned especially with the appearance of the dentition as achieved through its arrangement, form, and color.
forensic d. 1. the relation and application of dental facts to legal problems, as in using the teeth for identifying the dead; 2. the law in its bearing on the practice of d.. SYN: dental jurisprudence, forensic odontology, legal d..
legal d. SYN: forensic d..
operative d. usually, the individual restoration of teeth by means of metallic or nonmetallic materials. SYN: restorative d..
pediatric d. SYN: pedodontics.
preventive d. a philosophy and method of dental practice that seeks to prevent the initiation, progression, and recurrence of dental disease.
prosthetic d. SYN: prosthodontics.
public health d. that specialty of d. concerned with the prevention and control of dental diseases and promotion of oral health through organized community efforts.
restorative d. SYN: operative d..

dentition
dentition (den-tish′un)

The natural teeth, as considered collectively, in the dental arch; may be deciduous, permanent, or mixed. [L. dentitio, teething]
artificial d. SYN: denture (1) .
deciduous d. SYN: deciduous tooth.
delayed d. delayed eruption of the teeth.
first d. SYN: deciduous tooth.
mandibular d. SYN: mandibular dental arcade.
maxillary d. SYN: maxillary dental arcade.
natural d. d..
primary d. SYN: deciduous tooth.
retarded d. d. in which growth phenomena such as calcification, elongation, and eruption occur later than in the average range of normal variation as a result of some systemic metabolic dysfunction ( e.g., hypothyroidism).
secondary d. SYN: permanent tooth.
succedaneous d. SYN: permanent tooth.

dento- dento-

See dent-.

dentoalveolar
dentoalveolar (den′to-al-ve′o-lar)

Usually, denoting that portion of the alveolar bone immediately about the teeth; used also to denote the functional unity of teeth and alveolar bone.

dentode
dentode (den′tod)

An exact reproduction of a tooth on a gnathographically mounted cast.

dentoid
dentoid (den′toyd)

SYN: odontoid (1) . SEE ALSO: dentiform. [dent- + G. eidos, resemblance]

dentolegal
dentolegal (den-to-le′gal)

Relating to both dentistry and the law. See forensic dentistry.

dentoliva
dentoliva (den-to-li′va)

Rarely used term for oliva. [L. dens, tooth, + oliva, olive]

dentulous
dentulous (den′tu-lus)

Having natural teeth present in the mouth.

denture
denture (den′tur)

1. An artificial substitute for missing natural teeth and adjacent tissues. SYN: artificial dentition. 2. Sometimes used to denote the dentition of animals.
bar joint d. SYN: overlay d..
complete d. a dental prosthesis which is a substitute for the lost natural dentition and associated structures of the maxillae or mandible. SYN: full d..
design d. a planned visualization of the form and extent of a dental prosthesis, made after a study of all factors involved.
fixed partial d. a restoration of one or more missing teeth which cannot be readily removed by the patient or dentist; it is permanently attached to natural teeth or roots which furnish the primary support to the appliance. SYN: bridge (3) , fixed bridge.
full d. SYN: complete d..
immediate d. a complete or partial d. constructed for insertion immediately following the removal of natural teeth. SYN: immediate insertion d..
immediate insertion d. SYN: immediate d..
implant d. a d. that receives its stability and retention from a substructure which is partially or wholly implanted under the soft tissues of the d. basal seat. SEE ALSO: implant d. substructure, implant d. superstructure, subperiosteal implant.
interim d. a dental prosthesis to be used for a short interval of time for reasons of esthetics, mastication, occlusal support, or convenience, or to condition the patient to accept an artificial substitute for missing natural teeth until more definite prosthetic dental treatment can be provided. SYN: provisional d., temporary d..
overlay d. a complete d. that is supported by both soft tissue and natural teeth that have been altered so as to permit the d. to fit over them. The altered teeth may have been fitted with short or long copings, locking devices, or connecting bars. SYN: bar joint d., hybrid prosthesis, overdenture, telescopic d..
partial d. a dental prosthesis which restores one or more, but less than all, of the natural teeth and/or associated parts and which is supported by the teeth and/or the mucosa; it may be removable or fixed. SYN: bridgework.
partial d., distal extension a removable partial d. that is retained by natural teeth at one end of the d. base segments only, and in which a portion of the functional load is carried by the residual ridge.
provisional d. SYN: interim d..
removable partial d. a partial d. which supplies teeth and associated structures on a partially edentulous jaw, and which can be readily removed from the mouth. SYN: removable bridge.
telescopic d. SYN: overlay d..
temporary d. SYN: interim d..
transitional d. a partial d. which is to serve as a temporary prosthesis to which teeth will be added as more teeth are lost, and which will be replaced after postextraction tissue changes have occurred; a transitional d. may become an interim d. when all of the teeth have been removed from the dental arch.
treatment d. a dental prosthesis used for the purpose of treating or conditioning the tissues which are called upon to support and retain a d. base.
trial d. a setup of artificial teeth so fabricated that it may be placed in the patient's mouth to verify esthetics, for the making of records, or for any other operation deemed necessary before final completion of the d.. SYN: wax model d..
wax model d. SYN: trial d..

denture service
denture service

Those procedures performed in the diagnosis, construction, and maintenance of artificial substitutes for missing natural teeth.

denturist
denturist (den′tur-ist)

A dental technician who fabricates and fits dentures without supervision of a dentist.

Denucé
Denucé

Jean L.P., French surgeon, 1824–1889. See Denucé ligament.

denucleated
denucleated (de-noo′kle-a-ted)

Deprived of a nucleus.

denudation
denudation (den-u-da′shun)

Depriving of a covering or protecting layer; the act of laying bare, as in the removal of the epithelium from a surface. [L. de-nudo, to lay bare, fr. de, from, + nudus, naked]

denude
denude (de′nood)

To perform denudation.

Denys
Denys

Joseph, Belgian bacteriologist, 1857–1932. See D.-Leclef phenomenon.

deodorant
deodorant (de-o′der-ant)

1. Eliminating or masking a smell, especially an unpleasant one. 2. An agent having such an action; especially a cosmetic combined with an antiperspirant. SYN: deodorizer. [L. de- priv. + odoro, pp. -atus, to give an odor to, fr. odor, a smell]

deodorize
deodorize (de-o′der-iz)

To use a deodorant.

deodorizer
deodorizer (de-o′der-iz-er)

SYN: deodorant (2) .

deontology
deontology (de-on-tol′o-je)

The study of professional ethics and duties. [G. deon (deont-), that which is binding, pr. part. ntr. of dei, (impers.) it behooves, fr. deo, to bind, + logos, study]

deorsumduction
deorsumduction (de-or′sum-duk′shun)

Rotation of one eye downward. SYN: infraduction. [L. deorsum, downward, + duco, to lead]

deossification
deossification (de-os′i-fi-ka′shun)

Removal of the mineral constituents of bone. See demineralization. [L. de, from, + os, bone, + facio, to make]

deoxidation
deoxidation (de′oks-i-da′shun)

Depriving a chemical compound of its oxygen.

deoxidize
deoxidize (de-oks′i-diz)

To remove oxygen from its chemical combination.

deoxy- deoxy-

Prefix to chemical names of substances to indicate replacement of an –OH by an H. The older desoxy- has been retained in some instances.

deoxyadenosine
deoxyadenosine (dA, dAdo) (de-oks′e-a-den′o-sen)

2′-Deoxyribosyladenine, one of the four major nucleosides of DNA (the others being deoxycytidine, deoxyguanosine, and thymidine). The 5′ derivative is also an important component of one form of vitamin B₁₂. D. accumulates in individuals with severe combined immunodeficiency disease.

deoxyadenosine methylase
deoxyadenosine methylase

SYN: dam methylase.

5′-deoxyadenosylcobalamin
5′-deoxyadenosylcobalamin (de-oks′e-a-den-o-sil-ko-bal′a-min)

An active coenzyme form of vitamin B₁₂; required in the conversion of methylmalonyl-CoA to succinyl-CoA. A deficiency of d. will result in methylmalonic acidemia.

deoxyadenylic acid
deoxyadenylic acid (dAMP) (de-oks′e-ad-en-il′ik)

Deoxyadenosine monophosphate, a hydrolysis product of DNA, differing from adenylic acid in containing deoxyribose in place of ribose. SYN: adenine deoxyribonucleotide.

deoxybarbiturate
deoxybarbiturate (de-oks-e-bar-bit′ur-at)

A barbiturate compound lacking the oxygen atom at the #2 position in the ring; example of a d. is the antiepileptic drug, primidone. SEE ALSO: barbiturate.

deoxycholate
deoxycholate (DOC) (de-oks-e-ko′lat)

A salt or ester of deoxycholic acid.

deoxycholic acid
deoxycholic acid (de-oks-e-ko′lik)

7-D.; 3α,12α-dihydroxy-5β-cholanic acid;a bile acid and choleretic; used in biochemical preparations as a detergent.

deoxycoformycin
deoxycoformycin (de′oks-e-co-for-mi′sin)

A purine analog which acts as an antimetabolite; potent inhibitor of adenosine deaminase. Used as an antineoplastic agent. SEE ALSO: pentostatin.

2-deoxycoformycin
2-deoxycoformycin

SYN: pentostatin.

deoxycorticosterone
deoxycorticosterone (DOC) (de-oks′e-kor-ti-kos′ter-on)

An adrenocortical steroid, principally a biosynthetic precursor of corticosterone, that occasionally appears in adrenocortical secretions; a potent mineralocorticoid with no appreciable glucocorticoid activity. SYN: 21-hydroxyprogesterone, cortexone, deoxycortone, desoxycortone.
d. acetate acetate salt used for intramuscular injection for replacement therapy of the adrenocortical steroid.
d. pivalate pivalate salt of the steroid.

deoxycortone
deoxycortone (de-oks-e-kor′ton)

SYN: deoxycorticosterone.

deoxycytidine
deoxycytidine (de-oks-e-si′ti-den)

2′-Deoxyribosylcytosine, one of the four major nucleosides of DNA (the others being deoxyadenosine, deoxyguanosine, and thymidine).

deoxycytidylic acid
deoxycytidylic acid (dCMP) (de-oks′e-si-ti-dil′ik)

Deoxycytidine monophosphate, a hydrolysis product of DNA.

deoxyepinephrine
deoxyepinephrine (de-oks′e-ep-i-nef′ren)

A sympathomimetic amine used as a vasoconstrictor.

deoxyguanosine
deoxyguanosine (de-oks-e-gwan′o-sen)

2′-Deoxyribosylguanine, one of the four major nucleosides of DNA (the others being deoxyadenosine, deoxycytidine, and thymidine). Found to accumulate in individuals with purine nucleoside phosphorylase deficiency.

deoxyguanylic acid
deoxyguanylic acid (dGMP) (de-oks-e-gwan-il′ik)

Deoxyguanosine monophosphate, a hydrolysis product of DNA. SYN: guanine deoxyribonucleotide.

deoxyhexose
deoxyhexose (de-oks-e-heks′os)

A 6-carbon deoxy-sugar in which one OH is replaced by H.

deoxynucleoside
deoxynucleoside (de-oks′e-noo′kle-o-sid)

See deoxyribonucleoside.

deoxynucleotide
deoxynucleotide (de-oks′e-noo′kle-o-tid)

See deoxyribonucleoside.

deoxypentose
deoxypentose (de-oks-e-pen′tos)

A 5-carbon deoxy-sugar in which one OH is replaced by H.

deoxyriboaldolase
deoxyriboaldolase (de-oks′e-ri-bo-al′do-las)

SYN: deoxyribosephosphate aldolase.

deoxyribodipyrimidine photolyase
deoxyribodipyrimidine photolyase (de-oks′e-ri′bo-di-pi-rim′i-den)

An enzyme in yeast that is activated by light, whereupon it can reverse a previous photochemical reaction by cleaving the cyclobutane ring of the thymine dimer. SYN: dipyrimidine photolyase, photoreactivating enzyme.

deoxyribonuclease
deoxyribonuclease (DNAse, DNAase, DNase) (de-oks′e-ri-bo-noo′kle-as)

Any enzyme (phosphodiesterase) hydrolyzing phosphodiester bonds in DNA. SEE ALSO: endonuclease, nuclease.
acid d. SYN: d. II.
d. I, DNase I an endonuclease that cleaves primarily double-stranded DNA to a mixture of oligodeoxyribonucleotides, each ending in a 5′-phosphate; streptodornase is a similar enzyme. Under appropriate conditions, it can produce single-strand nicks in DNA; used in nick translation and in the mapping of hypersensitive sites. SYN: pancreatic d., thymonuclease.
d. II, DNase II an endonuclease that cleaves both strands of native DNA (as well as single-stranded DNA) to produce a mixture of oligodeoxynucleotides, each ending in a 3′-phosphate. SYN: acid d..
pancreatic d. SYN: d. I.
d. S₁ SYN: endonuclease S₁ Aspergillus.
spleen d. former name for micrococcal endonuclease.

deoxyribonucleic acid
deoxyribonucleic acid (DNA) (de-oks′e-ri′bo-noo-kle′ic)

The type of nucleic acid containing deoxyribose as the sugar component and found principally in the nuclei (chromatin, chromosomes) and mitochondria of animal and plant cells, usually loosely bound to protein (hence the term deoxyribonucleoprotein); considered to be the autoreproducing component of chromosomes and of many viruses, and the repository of hereditary characteristics. Its linear macromolecular chain consists of deoxyribose molecules esterified with phosphate groups between the 3′- and 5′-hydroxyl groups; linked to this structure are the purines adenine (A) and guanine (G) and the pyrimidines cytosine (C) and thymine (T). DNA may be open-ended or circular, single- or double-stranded, and many forms are known, the most commonly described of which is double-stranded, wherein the pyrimidines and purines cross-link through hydrogen bonding in the schema A-T and C-G, bringing two antiparallel strands into a double helix. Chromosomes are composed of double-stranded DNA; mitochondrial DNA is circular.
A-DNA a form of DNA in which the helix is right-handed and the overall appearance is short and broad.
antisense DNA the strand of DNA complementary to the one bearing the genetic message and from which it may be reconstructed. A DNA sequence complementary to a portion of mRNA. Used as potential therapeutic to stop transcription or translation of pathogens or inappropriately expressed host gene.
B-DNA a form of DNA in which the helix is right-handed and the overall appearance is long and thin.
blunt-ended DNA double-stranded DNA in which at least one of the ends has no unpaired bases.
competitor DNA dNA from a test organism that is denatured and then used in in vitro hybridization experiments in which it competes with DNA (homologous) from a reference organism; used to determine the relationship of the test organism to the reference organism.
complementary DNA (cDNA) 1. single-stranded DNA that is complementary to messenger RNA; 2. dNA that has been synthesized from mRNA by the action of reverse transcriptase.
extrachromosomal DNA dNA that occurs naturally outside of the nucleus ( e.g., mitochondrial DNA).
DNA fingerprinting a technique used to compare individuals by molecular genotyping. DNA isolated from a biological specimen is digested and fractionated. Southern hybridization with a radiolabeled repetitive DNA provides an autoradiographic pattern unique to the individual. SYN: DNA profiling, DNA typing.A technique developed in 1985 for comparing sets of DNA by locating identical sequences of nucleotides. Forensic applications of DNA fingerprinting are based on the premise that no 2 persons have exactly the same genetic makeup. The most distinctive features of an individual's genome are not the genes themselves but the variable number of tandem repeats (VNTRs) that occur between genes. While these do not transmit genetic information, they are highly consistent within the cells of an individual and highly variable from one individual to another. In DNA fingerprinting, the specimen is split into nucleotide fragments by treatment with restriction enzymes and then subjected to gel electrophoresis so as to yield a characteristic pattern of banding. Radioactive probes, composed of short nucleotide sequences (10–15 base pairs), then identify sites of tandem repeats and hybridize with them. Comparing the results from 2 or more DNA sources reveals their degree of relatedness. DNA fingerprinting offers a statistical basis for evaluating the probability that samples of blood, hair, semen, or tissue have originated from a given person. It also offers a means of determining lineages of humans and animals. The U.S. National Academy of Sciences has cautiously endorsed the use of DNA fingerprints as criminal evidence, while calling for further research and standardization of the technique.
genomic DNA dNA that contains both introns and exons.
junk DNA selfish DNA; that portion of DNA that is not transcribed and expressed, comprising a major fraction of the base pairs of the human genome; its function is not known.
DNA ligase an enzyme that leads to the formation of a phosphodiester bond at a break of one strand in duplex DNA; a part of the DNA repair system.
linker DNA the DNA found between nucleosomes on chromatin; since it is not complexed to proteins as strongly as other forms of DNA, it is accessible to exonuclease hydrolysis.
DNA nucleotidylexotransferase an enzyme that can catalyze the addition of a nucleotide, presented as a nucleoside triphosphate, on a DNA or similar polydeoxynucleotide; has been used in DNA recombination studies to add nucleotides to form homopolymer tails. SYN: terminal addition enzyme, terminal deoxynucleotidyltransferase.
palindromic DNA a segment of DNA in which the sequence is symmetrical about its midpoint.
DNA polymerase nucleotidyltransferases.
DNA profiling SYN: DNA fingerprinting.
recombinant DNA altered DNA resulting from the insertion into the chain, by chemical, enzymatic, or biologic means, of a sequence (a whole or partial chain of DNA) not originally (biologically) present in that chain.
repetitive DNA a segment of DNA that consists of a linear array of multiple copies of the same sequence of nucleotides.
satellite DNA dNA in the satellite regions of acrocentric chromosomes.
sticky-ended DNA double-stranded DNA in which one of the strands protrudes from the other strand ( I.E., has a number of unpaired bases) at one end or more.
DNA typing SYN: DNA fingerprinting.
Z-DNA a form of DNA in which the helix is left-handed, and the overall appearance is elongated and slim.
zero time-binding DNA DNA that has become the duplex form at the start of a reassociation process.

deoxyribonucleoprotein
deoxyribonucleoprotein (DNP, Dnp) (de-oks′e-ri-bo-noo′kle-o-pro′ten)

The complex of DNA and protein in which DNA is usually found upon cell disruption and isolation.

deoxyribonucleoside
deoxyribonucleoside (de-oks′e-ri-bo-noo′kle-o-sid)

A nucleoside component of DNA containing 2-deoxy-d-ribose; the condensation product of deoxy-d-ribose with purines or pyrimidines.

deoxyribonucleotide
deoxyribonucleotide (de-oks′e-ri-bo-noo′kle-o-tid)

A nucleotide component of DNA containing 2-deoxy-d-ribose; the phosphoric ester of deoxyribonucleoside; formed in nucleotide biosynthesis.

deoxyribose
deoxyribose (de-oks-e-ri′bos)

A deoxypentose, 2-deoxy-d-ribose being the most common example, occurring in DNA and responsible for its name.
d. phosphate deoxyribonucleotide.

deoxyribosephosphate aldolase
deoxyribosephosphate aldolase (de-oks′e-ri-bos-fos′fat)

An enzyme catalyzing cleavage of 2-deoxy-d-ribose 5-phosphate to d-glyceraldehyde 3-phosphate and acetaldehyde. SYN: deoxyriboaldolase.

deoxyriboside
deoxyriboside (de-oks-e-ri′bo-sid)

Deoxyribose combined via its 1-O atom with a radical derived from an alcohol; not to be confused with deoxyribosyl compounds such as deoxyribonucleosides. Cf.:deoxyribosyl.

deoxyribosyl
deoxyribosyl (de-oks-e-ri′bo-sil)

The radical formed from deoxyribose by removal of the OH from the C-1 carbon; e.g., deoxyadenosine. Cf.:deoxyriboside.

deoxyribosyltransferases
deoxyribosyltransferases (de-oks′e-ri′bo-sil-trans′fer- as-es)

Enzymes that catalyze the transfer of 2-deoxy-d-ribose from deoxyribosides to free bases.

deoxyribotide
deoxyribotide (de-oks-e-ri′bo-tid)

Misnomer for deoxyribonucleotide or deoxynucleotide derived, by analogy with nucleoside-nucleotide, from incorrect usage of deoxyriboside.

deoxyribovirus
deoxyribovirus (de-ok′se-vi′rus)

SYN: DNA virus.

deoxythymidine
deoxythymidine (dT) (de-oks′e-thi′mi-den)

SYN: thymidine.

deoxythymidylic acid
deoxythymidylic acid (dTMP) (de-oks′e-thi-mi-dil′ik)

A component of DNA; originally and properly called thymidylic acid, but use of deoxy- is less ambiguous, as ribothymidylic acid is now known to exist. SYN: thymine deoxyribonucleotide.

deoxyuridine
deoxyuridine (de-oks′e-ur′i-den)

A derivative of uridine in which one or more of the hydroxyl groups on the ribose moiety has been replaced by a hydrogen; e.g., 2′-d. is a rare naturally occurring deoxynucleoside.

deozonize
deozonize (de-o′zo-niz)

To deprive of ozone.

dependence
dependence (de-pen′dens)

The quality or condition of relying upon, being influenced by, or being subservient to a person or object reflecting a particular need. [L. dependeo, to hang from]
anchorage d. the need of normal cells to have an appropriate surface to attach to in order for them to grow in culture.
substance d. a pattern of behavioral, physiologic, and cognitive symptoms that develop due to substance use or abuse; usually indicated by tolerance to the effects of the substance and withdrawal symptoms that develop when use of the substance is terminated.

dependency
dependency (de-pen′dens-e)

The state of being dependent.
pyridoxine d. with seizure an inherited disorder (autosomal recessive) apparently associated with deficient brain type I glutamate decarboxylase; seizures can be controlled with vitamin B₆.

Dependovirus
Dependovirus (de-pen′do-vi-rus)

A genus of small defective single-stranded DNA viruses in the family Parvoviridae that depend on adenoviruses for replication. SYN: adeno-associated virus, adenosatellite virus. [L. dependeo, to be dependent upon, + virus]

depersonalization
depersonalization (de-per′son-al-i-za′shun)

A state in which one loses the feeling of one's own identity in relation to others in one's family or peer group, or loses the feeling of one's own reality. SYN: d. syndrome.

de Pezzer
de Pezzer

O., 19th century French physician. See de Pezzer catheter.

dephasing
dephasing

In magnetic resonance imaging, following alignment by a radiofrequency pulse, the gradual loss of orientation of the magnetic atomic nuclei due to random molecular energy transfer or relaxation.

dephosphorylation
dephosphorylation (de-fos′for-i-la′shun)

Removal of a phosphoric group, usually hydrolytically and by enzyme action, from a compound.

depigmentation
depigmentation (de-pig-men-ta′shun)

Loss of pigment which may be partial or complete. SEE ALSO: achromia (1) .

depilate
depilate (dep′i-lat)

To remove hair by any means. Cf.:epilate. [L. de-pilo, pp. -atus, to deprive of hair, fr. de- neg. + pilo, to grow hair]

depilation
depilation (dep-i-la′shun)

SYN: epilation.

depilatory
depilatory (de-pil′a-to-re)

1. SYN: epilatory (1) . 2. An agent that causes the falling out of hair. SYN: epilatory (2) .
chemical d. a topically applied d. substance.

depletion
depletion (de-ple′shun)

1. The removal of accumulated fluids or solids. 2. A reduced state of strength from too many free discharges. 3. Excessive loss of a constituent, usually essential, of the body, e.g., salt, water, etc.
salt d. excessive loss of sodium chloride from the body in urine, sweat, etc.; a cause of secondary dehydration.
water d. reduction in the total volume of body water; dehydration.

depolarization
depolarization (de-po′lar-i-za′shun)

1. A relative reduction in magnitude of polarization; in nerve cells, d. may result from an increase in the permeability of the cell membrane to sodium ions. 2. The destruction, neutralization, or change in direction of polarity.
dendritic d. the loss of a negative charge in the dendrites of a nerve cell.

depolarize
depolarize (de-po′lar-iz)

To deprive of polarity.

depolymerase
depolymerase (de-pol′i-mer-as)

Name used originally, before hydrolytic action was understood, for an enzyme catalyzing the hydrolysis of a macromolecule to simpler components. See nuclease.

deposit
deposit (de-poz′it)

1. A sediment or precipitate. 2. A pathological accumulation of inorganic material in a tissue. [L. de-pono, pp. -positus, to lay down]
brickdust d. a sediment of urates in the urine. SYN: sedimentum lateritium.

depravation
depravation (dep′ra-va′shun)

SYN: depravity. [L. depravatio, fr. depravo, pp. -atus, to corrupt]

depraved
depraved (de-pravd′)

Deteriorated or degenerate; corrupt. [L. depravo, to corrupt]

depravity
depravity (de-prav′i-te)

A depraved act or the condition of being depraved. SYN: depravation.

deprenyl
deprenyl (de′pren-il)

An inhibitor of monoamine oxidase selective for the type B isozyme. The drug is used as an antiparkinsonian agent. It does not give rise to the hypertensive crisis that can occur when nonselective monoamine oxidase inhibitors are taken in the presence of dietary sources of tyramine. SYN: selegiline.

depressant
depressant (de-pres′ant)

1. Diminishing functional tone or activity. 2. An agent that reduces nervous or functional activity, such as a sedative or anesthetic. [L. de-primo, pp. -pressus, to press down]

depressed
depressed (de-prest′)

1. Flattened from above downward. 2. Below the normal level or the level of the surrounding parts. 3. Below the normal functional level. 4. Dejected; lowered in spirits.

depression
depression (de-presh′un) [TA]

1. Reduction of the level of functioning. 2. SYN: excavation (1) . 3. Displacement of a part downward or inward. 4. A temporary mental state or chronic mental disorder characterized by feelings of sadness, loneliness, despair, low self-esteem, and self-reproach; accompanying signs include psychomotor retardation or less frequently agitation, withdrawal from social contact, and vegetative states such as loss of appetite and insomnia. SYN: dejection (1) , depressive reaction, depressive syndrome. [L. depressio, fr. deprimo, to press down]
agitated d. d. with excitement and restlessness.
anaclitic d. impairment of an infant's physical, social, and intellectual development following separation from its mother or from a mothering surrogate; characterized by listlessness, withdrawal, and anorexia.
endogenous d. any depressive disorder occurring in the absence of external precipitants and believed to have a biologic origin. SYN: endogenomorphic d., nonreactive d..
exogenous d. similar signs and symptoms as endogenous d. but the precipitating factors are social or environmental and outside the individual.
involutional d. d. or psychosis first occurring in the involutional years (40 to 55 for women, 50 to 65 for men).
lingual salivary gland d. an indentation on the lingual surface of the mandible within which a portion of the submandibular gland lies; it appears radiographically as a sharply circumscribed ovoid radiolucency between the mandibular canal and the inferior border of the posterior mandible. SYN: Stafne bone cyst, static bone cyst.
major d. a mental disorder characterized by sustained d. of mood, anhedonia, sleep and appetite disturbances, and feelings of worthlessness, guilt, and hopelessness. Diagnostic criteria (DSM-IV) for a major depressive episode include a depressed mood, a marked reduction of interest or pleasure in virtually all activities, or both, lasting for at least 2 weeks. In addition, 3 or more of the following must be present: gain or loss of weight, increased or decreased sleep, increased or decreased level of psychomotor activity, fatigue, feelings of guilt or worthlessness, diminished ability to concentrate, and recurring thoughts of death or suicide. See endogenous d., exogenous d., bipolar disorder. SYN: clinical d., major depressive disorder.Approximately 20 million persons a year suffer depressive illness in the U.S. About 10% of men and 25% of women experience major d. at some time in their lives, and 15–30% of these commit suicide. The negative impact of this disease on the economy of the U.S. is estimated at $16 billion annually. Risk factors for d. are drug or alcohol abuse, chronic physical illness, stressful life events, social isolation, a history of physical or sexual abuse, and a family history of depressive illness. D. can be masked by substance abuse. In elderly persons it may be mistaken for senile dementia, and vice versa; the two may coexist. The disorder is believed to represent an electrochemical malfunction of the limbic system involving disturbances in the metabolism of the neurotransmitters dopamine and serotonin. In persons with familial d., the number of glial cells in the subgenual prefrontal cortex is significantly smaller than in mentally healthy persons. Treatment with psychopharmaceutical agents, including tricyclic antidepressants, selective serotonin reuptake inhibitors (SSRIs), monoamine oxidase (MAO) inhibitors, and others, effectively controls most cases of clinical d.. Cognitive psychotherapy has demonstrated some success in reversing d.. Refined methods of electroconvulsive shock therapy (ECT) have been used with increasing frequency since the 1980s, generally for cases that do not respond to other treatment. Even in severe d. the response rate with ECT is 80% or higher. This mode of therapy has a faster onset of action, causes fewer side effects than drug therapy, and is particularly useful in elderly patients.
nonreactive d. SYN: endogenous d..
d. of optic disk [TA] the normally occurring d. or pit in the center of the optic disk. SYN: excavatio disci [TA] , excavatio papillae, excavation of optic disk, physiologic cup, physiologic excavation.
pacchionian depressions SYN: granular foveolae, under foveola.
postdrive d. slowing of the heart, often with a rate-dependent blockade of AV and/or VA conduction following rapid atrial stimulation.
pterygoid d. SYN: pterygoid fovea.
reactive d. a psychological state occasioned directly by an intensely sad external situation (frequently loss of a loved person), relieved by the removal of the external situation ( e.g., reunion with a loved person).
spreading d. a decrease of activity evoked by local stimulation of the cerebral cortex and spreading slowly over the whole cortex.

depressive
depressive (de-pres′iv)

1. Pushing down. 2. Pertaining to or causing depression.

depressor
depressor (de-pres′or)

1. A muscle that flattens or lowers a part. 2. Anything that depresses or retards functional activity. 3. An instrument or device used to push certain structures out of the way during an operation or examination. 4. An agent that decreases blood pressure. SYN: hypotensor, vasodepressor (2) . [L. de-primo, pp. -pressus, to press down]
tongue d. an instrument with a broad flat extremity used for pressing down the tongue to facilitate examination of the oral cavity and pharynx.

deprivation
deprivation (dep′ri-va′shun)

Absence, loss, or withholding of something needed.
emotional d. lack of adequate and appropriate interpersonal or environmental experiences, or both, usually in the early developmental years.
sensory d. diminution or absence of usual external stimuli or perceptual experiences, commonly resulting in psychological distress and aberrant functioning if continued too long.

depsipeptide
depsipeptide (dep′se-pep′tid)

An oligo- or polypeptide containing one or more ester bonds as well as peptide bonds. SEE ALSO: peptolide. [G. deseo, to knead, blend, + peptide]

depth
depth (depth)

Distance from the surface downward.
anesthetic d. the degree of central nervous system depression produced by a general anesthetic agent; a function of potency of the anesthetic and the concentration in which it is administered.
focal d., d. of focus the greatest distance through which an object point can be moved while maintaining a clear image. SYN: penetration (3) .

deptropine citrate
deptropine citrate (dep′tro-pen)

An antihistaminic agent with anticholinergic properties. SYN: dibenzheptropine citrate.

depulization
depulization (de-pu′li-za′shun)

Destruction of fleas which convey the plague bacillus from animals to humans. [L. de, from, + pulex (pulic-), flea]

depurant
depurant (dep′u-rant)

1. An agent or means used to effect purification. 2. An agent that promotes the excretion and removal of waste material. [L. de- intens. + puro, pp. -atus, to make pure]

depuration
depuration (dep-u-ra′shun)

Purification; removal of waste products or foul excretions.

depurative
depurative (dep′u-ra-tiv)

Tending to depurate; depurant.

dequalinium acetate
dequalinium acetate (de-kwah-lin′e-um)

An antimicrobial agent. SYN: decamine.

dequalinium chloride
dequalinium chloride

Dequalinium acetate, with chloride replacing acetate, used as an antimicrobial agent primarily in lozenges for the treatment of mouth and throat infections.

de Quervain
de Quervain

Friedrich Joseph, Swiss surgeon, 1868–1940. See de Quervain disease, de Quervain tenosynovitis, de Quervain thyroiditis.

deradelphus
deradelphus (dar-a-del′fus)

Conjoined twins with a single head and neck and separate bodies below the thoracic level. See conjoined twins, under twin. [G. dere, neck, + adelphos, brother]

derailment
derailment (de-ral′ment)

A symptom of a thought disorder in which one constantly gets “off the track” in one's thoughts and speech; similar to loosening of association.

deranencephaly
deranencephaly, deranencephalia (dar-an′en-sef′a-le, -se-fa′le-a)

1. Congenital malformation in which the head is absent, although there is a rudimentary neck. 2. Defect of the brain and upper part of the spinal cord. [G. dere, neck, + an-, priv., + kephale, head]

derangement
derangement (de-ranj′ment)

1. A disturbance of the regular order or arrangement. 2. Rarely used term for a mental disturbance or disorder. [Fr.]

Dercum
Dercum

Francis X., U.S. neurologist, 1856–1931. See D. disease.

derealization
derealization (de-re′a-li-za′shun)

An alteration in one's perception of the environment such that things that are ordinarily familiar seem strange, unreal, or two-dimensional.

dereism
dereism (de′re-izm)

Mental activity in fantasy in contrast to reality. [L. de, away, + res, thing]

dereistic
dereistic (de-re-is′tik)

Living in imagination or fantasy with thoughts that are incongruent with logic or experience.

derencephalia
derencephalia (dar-en-se-fa′le-a)

SYN: derencephaly.

derencephalocele
derencephalocele (dar-en-sef′a-lo-sel)

In derencephaly, protrusion of the rudimentary brain through a defect in the upper cervical spinal canal. [G. dere, neck, + enkephalos, brain, + kele, hernia]

derencephaly
derencephaly (dar-en-sef′a-le)

Cervical rachischisis and anencephaly, a malformation involving an open cranial vault with a rudimentary brain usually crowded back toward bifid cervical vertebrae. SYN: derencephalia. [G. dere, neck, + enkephalos, brain]

derepression
derepression (de-re-presh′un)

A homeostatic mechanism for regulating enzyme production in an inducible enzyme system: an inducer, usually a substrate of a specific enzyme pathway, by combining with an active repressor (produced by a regulator gene) deactivates it; the release of the previously repressed operator is followed by enzyme production.

derivation
derivation (dar-i-va′shun)

1. The source or process of an evolution. SYN: revulsion. 2. The drawing of blood or the body fluids to one part to relieve congestion in another. [L. derivatio, fr. derivo, pp. -atus, to draw off, fr. rivus, a stream]

derivative
derivative (de-riv′a-tiv)

1. Relating to or producing derivation. 2. Something produced by modification of something preexisting. 3. Specifically, a chemical compound that may be produced from another compound of similar structure in one or more steps, as in replacement of H by an alkyl, acyl, or amino group.

derm- derm-, derma-

The skin; corresponds to L. cut-. See entries under cut. [G. derma]

dermabrader
dermabrader (derm′a-brad-er)

A motor-driven device used in dermabrasion.

dermabrasion
dermabrasion (der-ma-bra′zhun)

Operative procedure to efface acne scars or pits performed with sandpaper, rotating wire brushes, or other abrasive materials.

Dermacentor
Dermacentor (der-ma-sen′ter)

An ornate, characteristically marked genus of hard ticks (family Ixodidae) that possess eyes and 11 festoons; it consists of some 20 species whose members commonly attack dogs, humans, and other mammals. [derm- + G. kentor, a goader]
D. albopictus the winter tick, a species found principally on horses, cattle, elk, moose, and deer in Canada and the northern and western United States; it is a one-host tick, but humans are sometimes attacked when skinning or dressing deer.
D. andersoni the wood tick; the vector of Rocky Mountain spotted fever; also transmits tularemia and causes tick paralysis; there are characteristic black and white markings on the large scutum of the male.
D. marginatus a tick species found across Europe and the vector of a human rickettsiosis caused by Rickettsia slovaca.
D. occidentalis the Pacific Coast tick, a species found on all domestic herbivores, deer, dogs, humans, and other animals in California and Oregon.
D. reticulatus a common species attacking sheep, oxen, goats, and deer, and sometimes troublesome to humans; it is found in Europe, Asia, and America.
D. variabilis the American dog tick, a species that is a common pest of dogs along the eastern seaboard of the U.S., a vector of tularemia, and a principal vector of Rickettsia rickettsii which causes Rocky Mountain spotted fever in the central and eastern U.S.; may also cause tick paralysis.

Dermacoccus
Dermacoccus (der-ma-kok′us)

A genus of Gram-positive, aerobic cocci found on human skin.

dermad
dermad (der′mad)

In the direction of the outer integument. [derm- + L. ad, to]

dermal
dermal (der′mal)

Relating to the skin. SYN: dermatoid (2) .

Dermanyssus gallinae
Dermanyssus gallinae (der-ma-nis′us ga-le′-ne)

The red hen-mite, a parasite of chickens, pigeons, and other birds; it sometimes attacks humans and causes an itching eruption, especially in sensitized individuals. SYN: Acarus gallinae. [derm- + G. nysso, to prick; L. gallina, hen]

dermat- dermat-

The skin. SEE ALSO: derm-, dermato-, dermo-. [G. derma]

dermatalgia
dermatalgia (der-ma-tal′je-a)

Localized pain, usually confined to the skin. SYN: dermatodynia. [dermat- + G. algos, pain]

dermatitis
dermatitis, pl .dermatitides (der-ma-ti′tis, -tit′i-dez)

Inflammation of the skin. [derm- + G. -itis, inflammation]
actinic d. SYN: photodermatitis.
d. aestivalis eczema recurring during the summer.
allergic contact d. a delayed type IV allergic reaction of the skin with varying degrees of erythema, edema, and vesiculation resulting from cutaneous contact with a specific allergen. SYN: contact allergy.
ancylostoma d. SYN: cutaneous larva migrans.
d. artefacta self-induced skin lesions resulting from habitual rubbing, scratching or hair-pulling, malingering, or mental disturbance. SYN: factitial d., feigned eruption.
atopic d. d. characterized by the distinctive phenomena of atopy, including infantile and flexural eczema. SYN: atopic eczema.
berloque d., berlock d. a type of photosensitization resulting in deep brown pigmentation on exposure to sunlight after application of bergamot oil and other essential oils in perfumes and colognes.
blastomycetic d., d. blastomycotica cutaneous blastomycosis.
bubble gum d. allergic contact d. developing about the lips in children who chew bubble gum; caused by plastics in the gum substance.
d. calorica SYN: erythema ab igne.
caterpillar d. allergic contact d. caused by the larva of the brown-tail moth, puss caterpillar, gypsy moths, and other caterpillars. SYN: caterpillar rash.
chemical d. allergic contact d. or primary irritation d. due to application of chemicals; usually characterized by erythema, edema, and vesiculation of the exposed or contacted site, and in some cases acne or pigmentary disturbances.
d. combustionis inflammation of the skin following a burn.
contact d. a T lymphocyte–mediated d. (type IV hypersensitivity) resulting from cutaneous contact with a specific allergen (allergic contact d.) or irritant (nonallergic contact d.). SYN: contact hypersensitivity (1) .
contagious pustular d. SYN: orf virus.
cosmetic d. a cutaneous eruption that results from the application of a cosmetic; due to allergic sensitization or primary irritation.
diaper d. colloquially referred to as diaper rash; d. of thighs and buttocks resulting from exposure to urine and feces in infants' diapers. Formerly attributed to ammonia formation; moisture, bacterial growth, and alkalinity may all induce lesions. SEE ALSO: intertrigo. SYN: diaper rash.
d. exfoliativa infantum, d. exfoliativa neonatorum a generalized pyoderma accompanied by exfoliative d., with constitutional symptoms, affecting young infants, which may result from atopic d., Leiner disease, or staphylococcal scalded skin syndrome. SYN: impetigo neonatorum (1) .
exfoliative d. rapidly extending erythema followed in a few days by generalized exfoliation with scaling of the skin and associated in some cases with lymphadenopathy or loss of water and electrolytes; may be a drug reaction or associated with various benign dermatoses, lupus erythematosus, or lymphoma, or be of undetermined cause. SYN: Wilson disease (2) .
exudative discoid and lichenoid d. discoid resembling an exudative form of nummular eczema, occurs especially in Jewish males, with oval lesions on the penis, trunk, and face. SYN: Sulzberger-Garbe disease, Sulzberger-Garbe syndrome.
factitial d. SYN: d. artefacta.
d. gangrenosa infantum a bullous or pustular eruption, of uncertain origin, followed by necrotic ulcers or extensive gangrene in children under 2 years of age; if untreated, death may result from hematogenous infection, such as liver abscess. SYN: disseminated cutaneous gangrene, ecthyma gangrenosum, pemphigus gangrenosus (1) .
d. herpetiformis a chronic disease of the skin marked by a symmetric itching eruption of vesicles and papules that occur in groups; relapses are common; associated with gluten-sensitive enteropathy and IgA together with neutrophils beneath the epidermis of lesional and perilesional skin. SYN: Duhring disease.
d. hiemalis SYN: winter itch.
infectious eczematoid d. an inflammatory reaction of skin adjacent to the site of a pyogenic infection; e.g., purulent otitis, the area around a colostomy, or intranasal infection; thought to spread by autoinoculation.
irritant contact d. skin reactions ranging from erythema and scaling to necrotic burns resulting from nonimmunologic damage by chemicals in contact with the skin immediately or repeatedly.
mango d. a perioral contact d. resulting from sensitization to the resinous coating on the peel of the mango fruit.
meadow d., meadow grass d. a photoallergic reaction to contact with a plant containing furocoumarin in which the bizarre configuration of the eruption is that of the streaky pattern of the plant contact; often occurs after sunbathing.
d. medicamentosa SYN: drug eruption.
nickel d. allergic d. due to contact with, or in some cases ingestion of, nickel or other metals containing nickel ( e.g., stainless steel).
d. nodosa a papular eruption on the legs, related to onchocerciasis (q.v.).
d. nodularis necrotica a recurrent eruption of vesicles, papules, and papulonecrotic lesions on the buttocks and extensor surfaces of the extremities, accompanied by fever, sore throat, diarrhea, and eosinophilia; probably a variant of vasculitis, it can be of varying and increasing severity and duration and can occasionally involve the heart, kidneys, and gastrointestinal tract. SYN: Werther disease.
nummular d. SYN: nummular eczema.
papular d. of pregnancy intensely pruritic papular eruption of torso and extremities occurring throughout pregnancy, with no systemic toxicity; may be similar to pruritic urticarial papules and plaques of pregnancy.
d. pediculoides ventricosus SYN: straw itch.
primary irritant d. a frequently cumulative reaction of irritation on exposure of the skin to substances which are toxic to epidermal or connective tissue cells; lesions are usually erythematous and papular, but can be purulent or necrotic, depending on the nature of the toxic material applied.
proliferative d. SYN: dermatophilosis.
rat mite d. an eruption of wheals, papules, or vesicles caused by the rat mite.
d. repens SYN: pustulosis palmaris et plantaris. [L. creeping]
rhus d. contact d. caused by cutaneous exposure to urushiol from species of Toxicodendron (Rhus), such as poison ivy, oak, or sumac.
sandal strap d. allergic contact on the dorsal surfaces of the feet, caused by synthetic rubber sandal straps or additives to natural rubber.
schistosomal d. a sensitization response to repeated cutaneous invasion by cercariae of bird, mammal, or human schistosomes. SYN: swimmer's itch, water itch (2) .
seborrheic d., d. seborrheica a common scaly macular eruption that occurs primarily on the face, scalp (dandruff), and other areas of increased sebaceous gland secretion, especially during infancy and after puberty; the lesions are covered with a slightly adherent oily scale. Effectiveness of treatment with betaconazole supports an etiologic role for Pityrosporum ovale infection. SYN: seborrheic eczema, Unna disease.
solar d. a d. in photosensitive persons caused by exposure to the sun's rays.
stasis d. erythema and scaling of the lower extremities due to impaired venous circulation, seen commonly in older women or secondary to deep vein thrombosis, the latter with rapid onset and swelling.
subcorneal pustular d. SYN: subcorneal pustular dermatosis.
traumatic d. any d. caused by an irritant substance or by a physical agent.
d. vegetans a benign fungating granulomatous mass caused by chronic pyogenic infection. SYN: pyoderma vegetans.

dermato- dermato-

See derm-. [G. derma, skin]

dermatoarthritis
dermatoarthritis (der′ma-to-ar-thri′tis)

Associated skin disease and arthritis.
lipoid d. a multicentric reticulohistiocytosis.

Dermatobia
Dermatobia (der-ma-to′be-a)

A genus of flies (family Oestridae) found in tropical America. [dermato- + G. bios, way of living]
D. cyaniventris SYN: D. hominis.
D. hominis a large, blue, brown-winged species whose larvae develop in open boillike lesions in the skin of humans, many domestic animals, and some fowl. It is a very serious and damaging cattle parasite and frequently attacks small children in Central and South America. Its eggs are laid on the legs or abdomen of another insect, such as the mosquito; the eggs later hatch, when stimulated by warmth or other factors, to release the botfly larvae on the skin of the mosquito's bloodmeal host, and the larvae quickly invade the skin to initiate myiasis. SYN: D. cyaniventris, human botfly, skin botflies, warble botfly.

dermatobiasis
dermatobiasis (der′ma-to-bi′a-sis)

Infection of humans and animals with larvae of the fly Dermatobia hominis. SYN: human botfly myiasis.

dermatocellulitis
dermatocellulitis (der′ma-to-sel-u-li′tis)

Inflammation of the skin and subcutaneous connective tissue.

dermatochalasis
dermatochalasis (der′ma-to-ka-la′sis)

A congenital or acquired condition characterized by deficient elastic fibers of the skin, which may hang in folds; vascular anomalies may be present; inheritance is either autosomal dominant or recessive, the latter sometimes in association with pulmonary emphysema and diverticula of the alimentary tract or bladder. The dominant form is caused by mutation in the elastin gene (ELN) on 7q. There is also an X-linked form that is due to mutation in the Menkes gene (MNK), encoding copper-transporting ATPase on Xq. SYN: cutis laxa, generalized elastolysis, loose skin. [conjunctiva + G. chalasis, a loosening]

dermatoconiosis
dermatoconiosis (der′ma-to-ko-ni-o′sis)

An occupational dermatitis caused by local irritation from dust. [dermato- + G. konis, dust, + -osis, condition]

dermatocyst
dermatocyst (der′ma-to-sist)

A cyst of the skin.

dermatodynia
dermatodynia (der′ma-to-din′e-a)

SYN: dermatalgia. [dermato- + G. odyne, pain]

dermatofibroma
dermatofibroma (der′ma-to-fi-bro′ma)

A slowly growing benign skin nodule consisting of poorly demarcated cellular fibrous tissue enclosing collapsed capillaries, with scattered hemosiderin-pigmented and lipid macrophages. The following terms are considered by some to be synonymous with, and by others to be varieties of, d.: sclerosing hemangioma (2), fibrous histiocytoma, nodular subepidermal fibrosis. SYN: fibrous histiocytoma, sclerosing hemangioma (2) .

dermatofibrosarcoma protuberans
dermatofibrosarcoma protuberans (der′ma-to-fi′bro-sar-ko′ma pro-too′ber-ans)

A relatively slowly growing dermal neoplasm consisting of one or several firm nodules that are usually covered by dark red-blue skin, which tends to be fixed to the palpable masses; histologically, the neoplasm resembles a cellular dermatofibroma with a pronounced storiform pattern; metastases are unusual, but the incidence of recurrence is fairly high.
pigmented d. an uncommon variant of d. containing heavily pigmented dendritic melanocytes scattered between spindle cells of the tumor. SYN: Bednar tumor, storiform neurofibroma.

dermatofibrosis lenticularis disseminata
dermatofibrosis lenticularis disseminata (der′ma-to-fi-bro′sis len-tik-u-la′ris di-sem-i-na′ta) [MIM*166700]

Small papules or discs of increased dermal elastic tissue appearing in early life; when osteopoikilosis is also present, the condition is called osteodermatopoikilosis or Buschke-Ollendorf syndrome; autosomal dominant inheritance.

dermatoglyphics
dermatoglyphics (der′ma-to-glif′iks)

1. The configurations of the characteristic ridge patterns of the volar surfaces of the skin; in the human hand, the distal segment of each digit has three types of configurations: whorl, loop, and arch. SEE ALSO: fingerprint. 2. The science or study of these configurations or patterns. [dermato- + glyphe, carved work]

dermatograph
dermatograph (der-mat′o-graf)

The linear wheal made in the skin in dermatographism.

dermatographism
dermatographism (der-ma-tog′ra-fizm)

A form of urticaria in which whealing occurs in the site and in the configuration of application of stroking (pressure, friction) of the skin. The resulting white line response appears early in flares of atopic dermatitis. SYN: autographism, factitious urticaria, skin writing. [dermato- + G. grapho, to write]

dermatoid
dermatoid (der′ma-toyd)

1. Resembling skin. SYN: dermoid (1) . 2. SYN: dermal.

dermatologist
dermatologist (der-ma-tol′o-jist)

A physician who specializes in the diagnosis and treatment of cutaneous diseases and related systemic diseases.

dermatology
dermatology (der-ma-tol′o-je)

The branch of medicine concerned with the study of the skin, diseases of the skin, and the relationship of cutaneous lesions to systemic disease. [dermato- + G. logos, study]

dermatolysis
dermatolysis (der-ma-tol′i-sis)

Loosening of the skin or atrophy of the skin by disease; erroneously used as a synonym for cutis laxa. SYN: dermolysis. [dermato- + G. lysis, a loosening]

dermatoma
dermatoma (der-ma-to′ma)

A circumscribed thickening or hypertrophy of the skin. [dermato- + G. -oma, tumor]

dermatome
dermatome (der′ma-tom)

1. An instrument for cutting thin sections of epidermis/dermis for grafting, or excising small lesions. 2. The dorsolateral part of an embryonic somite. SYN: cutis plate. 3. The area of skin supplied by cutaneous branches from a single spinal nerve; neighboring dermatomes can overlap. SYN: dermatomal distribution, dermatomic area. [dermato- + G. tome, a cutting]

dermatomegaly
dermatomegaly (der′ma-to-meg′a-le)

Congenital or acquired defect in which the skin hangs in folds; may be part of a syndrome or may occur in isolation as cutis laxa, dermatochalasis, or dermatolysis. [dermato- + G. megas, large]

dermatomere
dermatomere (der′ma-to-mer)

A metameric area of the embryonic integument. [dermato- + G. meros, part]

dermatomycosis
dermatomycosis (der′ma-to-mi-ko′sis)

Fungus infection of the skin caused by dermatophytes, yeasts, and other fungi. Cf.:dermatophytosis.
d. pedis SYN: tinea pedis.

dermatomyoma
dermatomyoma (der′ma-to-mi-o′ma)

SYN: leiomyoma cutis. [dermato- + G. mys, muscle, + -oma, tumor]

dermatomyositis
dermatomyositis (der′ma-to-mi-o-si′tis)

A progressive condition characterized by symmetric proximal muscular weakness with elevated serum levels of muscle enzymes and a skin rash, typically a purplish-red erythema on the face, and edema of the eyelids and periorbital tissue; affected muscle tissue shows degeneration of fibers with a chronic inflammatory reaction; occurs in children and adults, and in the latter may be associated with visceral cancer or other disorders of connective tissue. [dermato- + G. mys, muscle, + -itis, inflammation]

dermatoneurosis
dermatoneurosis (der′ma-to-noo-ro′sis)

Any cutaneous eruption due to emotional stimuli.

dermatonosology
dermatonosology (der′ma-to-no-sol′o-je)

The science of the nomenclature and classification of diseases of the skin. [dermato- + G. nosos, disease, + logos, treatise]

dermatopathia
dermatopathia (der′ma-to-path′e-a)

SYN: dermatopathy.
d. pigmentosa reticularis SYN: livedo reticularis.

dermatopathology
dermatopathology (der′ma-to-pa-thol′o-je)

Histopathology of the skin and subcutis, and study of the causes of skin disease.

dermatopathy
dermatopathy (der′ma-top′a-the)

Any disease of the skin. SYN: dermatopathia. [dermato- + G. pathos, suffering]

Dermatophagoides pteronyssinus
Dermatophagoides pteronyssinus (der-ma-tof-a-goy′dez ter-o-ni-si′nus)

A common species of cosmopolitan mites found in house dust and a common contributory cause of atopic asthma. [dermato- + G. phago, to eat; ptero- + G. nysso, to prick, stab]

dermatophilosis
dermatophilosis (der′ma-to-fi-lo′sis)

An infectious exudative dermatitis of cattle, sheep, goats, horses, and other animals (occasionally humans) caused by the bacterium Dermatophilus congolensis; severe (sometimes fatal) d. is seen in cattle in Africa and the Caribbean, invariably in association with Amblyomma variegatum tick infestations. SYN: proliferative dermatitis, streptothrichosis, streptotrichiasis, streptotrichosis.

Dermatophilus congolensis
Dermatophilus congolensis (der-ma-tof′i-lus kon-go-len′sis)

A species of motile, nonacid fast, aerobic to facultatively anaerobic, Gram-positive bacteria that is the etiologic agent of dermatophilosis; also causes proliferative dermatitis. [dermato- + G. philos, fond]

dermatophobia
dermatophobia (der′ma-to-fo′be-a)

Morbid fear of acquiring a skin disease. [dermatosis + G. phobos, fear]

dermatophylaxis
dermatophylaxis (der′ma-to-fi-lak′sis)

Protection of the skin against potentially harmful agents; e.g., infection, excessive sunlight, noxious agents. [dermato- + G. phylaxis, protection]

dermatophyte
dermatophyte (der′ma-to-fit)

A fungus that causes superficial infections of the skin, hair, and/or nails, i.e., keratinized tissues. Species of Epidermophyton, Microsporum, and Trichophyton are regarded as dermatophytes, but causative agents of tinea versicolor, tinea nigra, and cutaneous candidiasis are not so classified. [dermato- + G. phyton, plant]

dermatophytid
dermatophytid (der-ma-tof′i-tid)

An allergic manifestation of dermatophytosis at a site distant from that of the primary fungous infection. The lesions, usually small vesicles on the hands and/or arms, are devoid of the fungus and may become extensive, covering wide areas of the body and causing extreme discomfort to the patient. SEE ALSO: -id (1) , id reaction.

dermatophytosis
dermatophytosis (der′ma-to-fi-to′sis)

An infection of the hair, skin, or nails caused by any one of the dermatophytes. The lesions may occur at any site on the body and, on the skin, are characterized by erythema, small papular vesicles, fissures, and scaling. Common sites of infection are the feet (tinea pedis), nails (onychomycosis), and scalp (tinea capitis). Cf.:dermatomycosis.

dermatopolyneuritis
dermatopolyneuritis (der′ma-to-pol′e-noo-ri′tis)

SYN: acrodynia (2) .

dermatorrhagia
dermatorrhagia (der′ma-to-ra′je-a)

Hemorrhage from or into the skin. [dermato- + G. rhegnymi, to break forth]

dermatorrhea
dermatorrhea (der′ma-to-re′a)

An excessive secretion of the sebaceous or sweat glands of the skin. [dermato- + G. rhoia, flow]

dermatorrhexis
dermatorrhexis (der′ma-to-rek′sis)

Rupture of the skin; e.g., as is seen in striae cutis distensae or in Ehlers-Danlos syndrome. [dermato- + G. rhexis, rupture]

dermatoscopy
dermatoscopy (der-ma-tos′ko-pe)

Inspection of the skin, usually with the aid of a lens or by epiluminescence microscopy, (q.v.). [dermato- + G. skopeo, to view]

dermatosis
dermatosis, pl .dermatoses (der-ma-to′sis, -sez)

Nonspecific term used to denote any cutaneous abnormality or eruption. [dermato- + G. -osis, condition]
acute febrile neutrophilic d. a rare d., predominant in women, of rapid onset and characterized by plaquelike lesions, usually multiple, on the face, neck, and upper extremities, accompanied by conjunctivitis, mucosal lesions, fever, malaise, arthralgia, and peripheral blood neutrophilia in many cases; biopsy reveals polymorphonuclear infiltrate of the dermis; rapid remission occurs with systemic steroid therapy. SYN: Sweet disease.
ashy d. SYN: erythema dyschromicum perstans.
Bowen precancerous d. SYN: Bowen disease.
chronic bullous d. of childhood a rare, self-limiting bullous disease, chiefly of the trunk, perioral, and pelvic areas, with onset in the first decade, successively less severe recurrences, and total remission at adolescence; linear epidermal basement membrane zone deposit of IgA is found in involved and in normal skin. SYN: linear IgA bullous disease in children.
dermolytic bullous d. SYN: epidermolysis bullosa dystrophica.
digitate d. See parapsoriasis en plaque. SYN: small plaque parapsoriasis.
juvenile plantar d. a painful dermatitis, occurring primarily in children, that causes the plantar skin to appear glazed and fissured; may be associated with hyperhidrosis.
lichenoid d. any chronic skin eruption, characterized clinically by induration and thickening of the skin with accentuation of skin markings, and microscopically by a bandlike lymphocytic infiltration of the papillary dermis.
d. medicamentosa SYN: drug eruption.
d. papulosa nigra dark brown papular lesions, observed in blacks, on the face and upper trunk; histologically and clinically, they resemble seborrheic keratoses.
pigmented purpuric lichenoid d. an eruption comprised of lichenoid papules variously pigmented from the hemosiderin of the associated purpura; found on the legs, usually in men over 40 years of age. SYN: Gougerot and Blum disease.
progressive pigmentary d. chronic purpura, especially of the legs in men, spreading to form red-brown patches and puncta described as cayenne pepper spots; associated microscopically with perivascular lymphocytic infiltration, diapedesis, and hemosiderosis. SYN: Schamberg fever.
radiation d. skin changes at the site of ionizing radiation, particularly erythema in the acute stage, temporary or permanent epilation, and chronic changes in the epidermis and dermis resembling actinic keratosis, from which squamous cell carcinoma may develop.
subcorneal pustular d. a pruritic chronic annular eruption of sterile vesicles and pustules beneath the stratum corneum. SYN: Sneddon-Wilkinson disease, subcorneal pustular dermatitis.
transient acantholytic d. a pruritic papular eruption, with histologic suprabasal acantholysis, of the chest, with scattered lesions of the back and lateral aspects of the extremities, lasting from a few weeks to several months; seen predominantly in males over 40. SYN: Grover disease.

dermatotherapy
dermatotherapy (der′ma-to-thar′a-pe)

Treatment of skin diseases.

dermatothlasia
dermatothlasia (der′ma-to-thla′ze-a)

An uncontrollable impulse to pinch and bruise the skin. [dermato- + G. thlasis, a bruising]

dermatotropic
dermatotropic (der′ma-to-trop′ik)

Having an affinity for the skin. SYN: dermotropic. [dermato- + G. trope, a turning]

dermatozoon
dermatozoon (der′ma-to-zo′on)

An animal parasite of the skin. [dermato- + G. zoon, animal]

dermatozoonosis
dermatozoonosis (der′ma-to-zo-o-no′sis, -zo-on′o-sis)

Infestation of the skin by an animal parasite. [dermato- + G. zoon, animal, + nosos, disease]

dermatrophia
dermatrophia, dermatrophy (der-ma-tro′fe-a, der-mat′ro-fe)

Atrophy or thinning of the skin.

dermenchysis
dermenchysis (der-men′ki-sis)

Rarely used term for subcutaneous administration of remedies. [derm- + G. enchysis, a pouring in]

dermis
dermis [TA]

A layer of skin composed of a superficial thin layer that interdigitates with the epidermis, the stratum papillare, and the stratum reticulare; it contains blood and lymphatic vessels, nerves and nerve endings, glands, and, except for glabrous skin, hair follicles. SYN: corium&star, cutis vera. [G. derma, skin]

dermo- dermo-

See derm-. [G. derma, skin]

Dermobacter
Dermobacter (der-mo-bak′ter)

A bacterial genus of nonmotile, non–spore-bearing Gram-positive rods, recovered on human skin. D. hominis has been associated with positive blood cultures.

dermoblast
dermoblast (der′mo-blast)

One of the mesodermal cells from which the dermis is developed. [dermo- + G. blastos, germ]

dermocyma
dermocyma (der′mo-si′ma)

Unequal conjoined twins in which the smaller parasite is buried in the integument of the autosite. [dermo- + G. kyma, fetus]

dermoid
dermoid (der′moyd)

1. SYN: dermatoid (1) . 2. SYN: d. cyst. [dermo- + G. eidos, resemblance]
inclusion d. SYN: epidermal cyst.

dermoidectomy
dermoidectomy (der-moy-dek′to-me)

Rarely used term for operative removal of a dermoid cyst. [dermoid + G. ektome, excision]

dermolysis
dermolysis (der-mol′i-sis)

SYN: dermatolysis.

dermonecrotic
dermonecrotic (der′mo-ne-krot′ik)

Pertaining to any application or illness which may cause necrosis of the skin.

dermopathy
dermopathy (der-mop′a-the)

SYN: dermatopathy.
diabetic d. small macules and papules of the extensor surfaces of the extremities, most commonly the shins of diabetics, which become atrophic, hyperpigmented, and occasionally undergo ulceration with scarring; may be a manifestation of microangiopathy.

dermophlebitis
dermophlebitis (der′mo-fle-bi′tis)

Inflammation of the superficial veins and the surrounding skin. [dermo- + G. phleps, vein, + -itis, inflammation]

dermoskeleton
dermoskeleton (der-mo-skel′e-ton)

SYN: exoskeleton (1) .

dermostenosis
dermostenosis (der′mo-ste-no′sis)

Pathologic contraction of the skin. [dermo- + G. stenosis, a narrowing]

dermotoxin
dermotoxin (der-mo-tok′sin)

A substance elaborated by a living agent, especially an exotoxin formed by bacteria, and characterized by its ability to cause pathologic changes in skin, e.g., erythema, degenerative changes, necrosis.

dermotropic
dermotropic (der-mo-trop′ik)

SYN: dermatotropic.

dermovascular
dermovascular (der-mo-vas′ku-lar)

Pertaining to the blood vessels of the skin. [dermo- + L. vasculum, small vessel]

derodidymus
derodidymus (dar′o-did′i-mus)

SYN: dicephalus diauchenos. [G. dere, neck, + didymos, twin]

derotation
derotation (de-ro-ta′shun)

1. A turning back. 2. In orthopedics, the correction of a rotation deformity by turning or rotating the deformed structure toward a normal position. [L. de, away, + rotatio, turning]

DES
DES

Abbreviation for diethylstilbestrol.

des- des-

In chemistry, a prefix indicating absence of some component of the principal part of the name; largely replaced by “de-” ( e.g., deoxyribonucleic acid, dehydro-) but retained where “de-” could be taken for d- or d-, as part of “desmo-” ( e.g., desmosterol), and in such terms as desoxycortone.

desamidize
desamidize (de-sam′i-diz)

SYN: deamidize.

De Sanctis
De Sanctis

Carlo, Italian psychiatrist, *1888. See D.-Cacchione syndrome.

desaturate
desaturate (de-sat′u-rat)

To produce desaturation.

desaturation
desaturation (de′sat-u-ra′shun)

1. The act, or the result of the act, of making something less completely saturated; more specifically, the percentage of total binding sites remaining unfilled, e.g., when hemoglobin is 70% saturated with oxygen and nothing else, its d. is 30%. Cf.:saturation (5) . 2. The process or reaction of removal of two hydrogen atoms from a molecule, resulting in the formation of a double bond.

Desault
Desault

Pierre-Joseph, French surgeon, 1744–1795. See D. bandage.

Descartes
Descartes, Cartesius

René, French philosopher, mathematician, physiologist, 1596–1650. The founder of modern philosophy and proponent of the mechanistic school or iatromathematical school. See D. law.

Descemet
Descemet

Jean, French physician, 1732–1810. See D. membrane.

descemetitis
descemetitis (des′e-me-ti′tis)

Inflammation of Descemet membrane.

descemetocele
descemetocele (des-e-met′o-sel)

A bulging forward of Descemet membrane caused by the destruction of the substance of the cornea by infection.

descendens
descendens (de-sen′denz)

SYN: descending. [L.]
d. cervicalis SYN: inferior root of ansa cervicalis.
d. hypoglossi SYN: superior root of ansa cervicalis.

descending
descending (de-send′ing)

Running downward or toward the periphery. SYN: descendens. [L. de-scendo, pp. -scensus, to come down, fr. scando, to climb]

descensus
descensus (de-sen′sus)

A falling away from a higher position. SEE ALSO: ptosis, procidentia. SYN: descent (1) . [L.]
d. testis descent of the testis from the abdomen into the scrotum during the seventh and eighth months of intrauterine life.
d. uteri SYN: prolapse of the uterus.
d. ventriculi SYN: gastroptosis.

descent
descent (de-sent′)

1. SYN: descensus. 2. In obstetrics, the passage of the presenting part of the fetus into and through the birth canal. [L. descensus]

Deschamps
Deschamps

Joseph F.L., French surgeon, 1740–1824. See D. needle.

desensitization
desensitization (de-sen′si-ti-za′shun)

1. The reduction or abolition of allergic sensitivity or reactions to the specific antigen (allergen). SYN: antianaphylaxis. 2. The act of removing an emotional complex. SYN: hyposensitization.
heterologous d. stimulation by one agonist which leads to a broad pattern of unresponsiveness to further stimulation by a variety of other agonists.
homologous d. loss of sensitivity only to the class of agonist used to desensitize the tissue.
systematic d. a type of behavior therapy for eliminating phobias or anxieties: the patient and therapist construct a list of imagined scenes eliciting the phobia, ranked from least to most anxiety producing; the patient then is trained in deep muscle relaxation, and is repeatedly asked to imagine him or herself in the presence of the least anxiety-producing scene on the list until the patient feels fully relaxed while doing so; the procedure is repeated for each scene on the list until the patient develops the capacity to feel relaxed with any of the anxiety-producing scenes; real life scenes are then substituted for the imagined scenes. SYN: reciprocal inhibition (2) .

desensitize
desensitize (de-sen′si-tiz)

1. To reduce or remove any form of sensitivity. 2. To effect desensitization (1). 3. In dentistry, to eliminate or subdue the painful response of exposed, vital dentin to irritative agents or thermal changes.

deserpidine
deserpidine (de-ser′pi-den)

Ester alkaloid isolated from Rauwolfia canescens (family Apocynaceae) with the same actions and uses as reserpine.

desetope
desetope (de′se-top)

That part of the Class II major histocompatibility molecule that interacts with the antigen. The term d. is derived from determinant selection. [determinant selection + -tope]

desferrioxamine mesylate
desferrioxamine mesylate (des′far-e-ok′sa-men)

SYN: deferoxamine mesylate.

desflurane
desflurane (dés′floor′an)

An inhalation anesthetic with physical characteristics that provide rapid induction of and recovery from anesthesia.

deshydremia
deshydremia (des′hi-dre′me-a)

Hemoconcentration due to the loss of water from blood plasma. [L. de-, away from, + G. hydor, water, + haima, blood + -ia]

desiccant
desiccant (des′i-kant)

1. Drying; causing or promoting dryness. SYN: desiccative. 2. An agent that absorbs moisture; a drying agent. SYN: desiccator (1) . SYN: exsiccant. [L. de-sicco, pp. -siccatus, to dry up]

desiccate
desiccate (des′i-kat)

To dry thoroughly; to render free from moisture. SYN: exsiccate.

desiccation
desiccation (des-i-ka′shun)

The process of being desiccated. SYN: dehydration (4) , exsiccation (1) .

desiccative
desiccative (des-i-ka′tiv)

SYN: desiccant (1) .

desiccator
desiccator (des′i-ka-ter, tor)

1. SYN: desiccant (2) . 2. An apparatus, such as a glass chamber containing calcium chloride, sulfuric acid, or other drying agent, in which a material is placed for drying.
vacuum d. a d. that can be evacuated.

desipramine hydrochloride
desipramine hydrochloride (des-ip′ra-men)

A dibenzazepine derivative; an antidepressant similar to imipramine hydrochloride. Selectively blocks reuptake of norepinephrine back into central aminergic neurons.

deslanoside
deslanoside (des-lan′o-sid)

A rapidly acting steroid glycoside obtained from lanatoside C (Digitalis lanata) by alkaline hydrolysis; a cardiotonic.

desm- desm-

See desmo-.

Desmarres
Desmarres

Louis A., French ophthalmologist, 1810–1882. See D. dacryoliths, under dacryolith, D. retractor.

desmin
desmin (dez′minz)

Proteins found in intermediate filaments that copolymerizes with vimentin to form constituents of connective tissue, cell walls, filaments, etc. Found in Z disk of skeletal and cardiac muscle cells.

desmitis
desmitis (dez-mi′tis)

Inflammation of a ligament. [desm- + G. -itis, inflammation]

desmo- desmo-, desm-

Fibrous connection; ligament. [G. desmos, a band]

desmocranium
desmocranium (dez-mo-kra′ne-um) [TA]

The mesenchymal primordium of the cranium.

desmodentium
desmodentium [TA]

The collagen fibers, running from the cementum to the alveolar bone, that suspend a tooth in its socket; they include apical, oblique, horizontal, and alveolar crest fibers, indicating that the orientation of the fibers varies at different levels. SYN: desmodontium [TA] , periodontal fiber&star, periodontal ligament fibers.

desmodontium
desmodontium [TA]

SYN: desmodentium.

Desmodus
Desmodus (dez′mo-dus)

A blood-feeding genus of Chiroptera, known generally as vampire bats, found in Trinidad, Mexico, and Central and South America; D. artibaeus, D. rotundus, and D. rufus, three species present in Trinidad and South America, are reservoir hosts of rabies virus. [desmo- + G. odous, tooth]

desmogenous
desmogenous (dez-moj′e-nus)

Of connective tissue or ligamentous origin or causation; e.g., denoting a deformity due to contraction of ligaments, fascia, or a scar. [desmo- + G. -gen, producing]

desmography
desmography (dez-mog′ra-fe)

A description of, or treatise on, the ligaments. [desmo- + G. grapho, to describe]

desmoid
desmoid (dez′moyd)

1. Fibrous or ligamentous. 2. A nodule or relatively large mass of unusually firm scarlike connective tissue resulting from active proliferation of fibroblasts, occurring most frequently in the abdominal muscles of women who have borne children; the fibroblasts infiltrate surrounding muscle and fascia. SYN: abdominal fibromatosis, d. tumor. [desmo- + G. eidos, appearance, form]
extra-abdominal d. a deep-seated firm tumor, most frequently occurring on the shoulders, chest, or back of young men or women, consisting of collagenous fibrous tissue that infiltrates surrounding muscle; frequently recurs but does not metastasize.

desmolases
desmolases (dez′mo-la′sez)

Old and nonspecific term for enzymes catalyzing reactions other than those involving hydrolysis; e.g., those involving oxidation and reduction, isomerization, the breaking of carbon-carbon bonds.

desmology
desmology (dez-mol′o-je)

The branch of anatomy concerned with the ligaments. [desmo- + G. logos, study]

desmopathy
desmopathy (dez-mop′a-the)

Any disease of the ligaments. [desmo- + G. pathos, suffering]

desmoplasia
desmoplasia (dez-mo-pla′ze-a)

Hyperplasia of fibroblasts and disproportionate formation of fibrous connective tissue, especially in the stroma of a carcinoma. [desmo- + G. plasis, a molding]

desmoplastic
desmoplastic (des-mo-plas′tik)

1. Causing or forming adhesions. 2. Causing fibrosis in the vascular stroma of a neoplasm.

desmopressin
desmopressin (des-mo-pres′in)

An analog of vasopressin (antidiuretic hormone, ADH) possessing powerful antidiuretic activity.
d. acetate a synthetic analog of vasopressin and an antidiuretic hormone.

desmosine
desmosine (dez′mo-sen)

A cross-linking amino acid formed from lysyl residues found in elastin. [G. desmos, bond, fr. deo, to bind, + -ine]

desmosome
desmosome (dez′mo-som)

A site of adhesion between two epithelial cells, consisting of a dense attachment plaque separated from a similar structure in the other cell by a thin layer of extracellular material. SYN: bridge corpuscle, macula adherens. [desmo- + G. soma, body]

desmosterol
desmosterol (dez-mos′ter-ol)

5α-Cholesta-5,24-diene-3β-ol;postulated intermediate in cholesterol biosynthesis from lanosterol via zymosterol; accumulates after prolonged administration of substances interfering with cholesterol biosynthesis. SYN: 24-dehydrocholesterol.

desonide
desonide (des′o-nid)

An anti-inflammatory corticosteroid used in topical preparations.

desoximetasone
desoximetasone (des-ok-si-met′a-son)

An anti-inflammatory corticosteroid used in topical preparations.

desoxy- desoxy-

See deoxy-.

desoxycorticosterone
desoxycorticosterone (des-oks-e-kor′ti-kos-ter-on)

A steroid derived from the adrenal cortex with strong mineralocorticoid activity.

desoxycortone
desoxycortone (des-oks-e-kor′ton)

SYN: deoxycorticosterone.

despeciation
despeciation (de-spe′she-a′shun)

1. Alteration of, or loss of species characteristics. 2. Removal of species-specific antigenic properties from a foreign protein.

D'Éspine
D'Éspine

Jean H.A., French physician, 1846–1930. See D. sign.

despumation
despumation (des-pu-ma′shun)

1. The rising of impurities to the surface of a liquid. 2. The skimming off of impurities on the surface of a liquid. [L. de-spumo, pp. -atus, to skim, fr. spumo, to foam, fr. spuma, foam]

desquamate
desquamate (des′kwa-mat)

To shred, peel, or scale off, as the casting off of the epidermis in scales or shreds, or the shedding of the outer layer of any surface. [L. desquamo, pp. -atus, to scale off, fr. squama, a scale]

desquamation
desquamation (des-kwa-ma′shun)

The shedding of the cuticle in scales or of the outer layer of any surface.
branny d. SYN: defurfuration.

desquamative
desquamative (des-kwam′a-tiv)

Relating to or marked by desquamation.

desthiobiotin
desthiobiotin (des′thi-o-bi′o-tin)

A compound derived from biotin by the removal of the sulfur atom; a precursor of biotin in bacteria and molds; it can substitute for biotin in some microorganisms, but is without effect on or is inhibitory to the growth of others.

destrudo
destrudo (de-stroo′do)

Energy associated with the death or destructive instinct. [coinage on the analogy of libido fr. L. destruo, to destroy]

desulfhydrases
desulfhydrases (de′sulf-hi′dra-sez)

Enzymes or groups of enzymes catalyzing the removal of a molecule of H₂S or substituted H₂S from a compound, as in the conversion of cysteine to pyruvic acid by cysteine desulfhydrase (cystathionine γ-lyase). SYN: desulfurases.

desulfinase
desulfinase (de-sul′fi-nas)

Term sometimes applied to the enzyme (aspartate-4-decarboxylase) removing sulfite: 1) from cysteinesulfinate, an intermediate in cysteine degradation, yielding alanine; 2) from sulfinylpyruvate, previously postulated to be formed by deamination of cysteinesulfinate, yielding pyruvate; degradation of sulfinylpyruvate is now considered to be spontaneous, not requiring an enzyme.

Desulfotomaculum
Desulfotomaculum (de-sul-fo-to-mak′u-lum)

A genus of rod-shaped (straight or curved), anaerobic, chemoorganotrophic motile bacteria that stain Gram-negative but have Gram-positive cell walls. Found in soil, the rumen and elsewhere. The type species is D. nigrificans.
D. nigrificans a species found in spoiled foods showing “sulfur stinker ” spoilage as a result of hydrogen sulfide production. It is not pathogenic.

desulfurases
desulfurases (de-sul′fur-as-ez)

SYN: desulfhydrases.

desynchronous
desynchronous (de-sin′kron-us)

Lack of synchrony, as in brain waves. [de- + G. syn, with, + chronos, time]

DET
DET

Abbreviation for diethyltryptamine.

det.
det.

Abbreviation for L. detur, give. [let it be given]

detachment
detachment (de-tach′ment)

1. A voluntary or involuntary feeling or emotion that accompanies a sense of separation from normal associations or environment. 2. Separation of a structure from its support.
exudative retinal d. d. of the retina without retinal breaks, arising from inflammatory disease of choroid, retinal tumors, and retinal angiomatosis.
retinal d., d. of retina loss of apposition between the sensory retina and the retinal pigment epithelium. SYN: detached retina, separation of retina.
rhegmatogenous retinal d. retinal separation associated with a break, a hole, or a tear in the sensory retina.
vitreous d. separation of the peripheral vitreous humor from the retina.

detection
detection (de-tek′shun)

1. The act of discovery. 2. In chromatography, visualization of the separated material.

detector
detector (de-tek′ter, -tor)

The component of a laboratory instrument which detects the chemical or physical signal indicating the presence or quantity of the substance of interest.
solid-state d. a d. that uses a crystalline scintillating material rather than an ionization chamber to detect or measure radiation.

detergent
detergent (de-ter′jent)

1. Cleansing. 2. A cleansing or purging agent, usually salts of long-chain aliphatic bases or acids ( e.g., quaternary ammonium or sulfonic acid compounds) which, through a surface action that depends on their possessing both hydrophilic and hydrophobic properties, exert cleansing (oil-dissolving) and antibacterial effects; acridine derivatives ( e.g., acriflavine, proflavine) as well as other dyes ( e.g., brilliant green, crystal violet) have d. properties for the same reasons. SYN: detersive. [L. de-tergeo, pp. -tersus, to wipe off]
anionic detergents detergents, such as soaps (alkali metal salts of long-chain fatty acids), that carry a negative electric charge on a lipidlike molecule and exert a limited antibacterial effect.
cationic detergents detergents, such as the amine salts or quaternary ammonium or pyridinium compounds of long-chain fatty acids, that have positively charged groups attached to the larger hydrophobic portions.
zwitterionic d. SYN: zwittergents.

deterioration
deterioration (de-ter′i-o-ra′shun)

The process or condition of becoming worse. [L. deterior, worse]
alcoholic d. dementia occurring in persons chronically addicted to alcohol. See chronic alcoholism.
senile d. a slowly progressing decline in physical and mental health, apparently due to natural causes attendant upon the processes of aging. See Alzheimer disease.

determinant
determinant (de-ter′mi-nant)

The factor that contributes to the generation of a trait. [L. determans, determining, limiting]
allotypic determinants antigenic determinants of allotypes.
antigenic d. the particular chemical group of a molecule that determines immunological specificity. SYN: d. group.
disease determinants any variables that directly or indirectly influence the frequency of occurrence and/or the distribution of any given disease; they include specific disease agents, host characteristics, and environmental factors.
genetic d. any antigenic d. or identifying characteristic, particularly those of allotypes. SYN: genetic marker.
idiotypic antigenic d. SYN: idiotope.
isoallotypic determinants genetic determinants that are both isotypic and allotypic in that they appear on heavy chains of all members of at least one subclass of immunoglobulin but also on heavy chains of another subclass of the same species.
mathematical d. a formal algebraic operation on the terms of a square matrix of quantities, fundamental in solving multiple simultaneous equations and widely used in regression analysis, notably in epidemiology and quantitative genetics. If d. is zero, the equations have no unambiguous solution.

determination
determination (de-ter-mi-na′shun)

1. A change, for the better or for the worse, in the course of a disease. 2. A general move toward a given point. 3. The measurement or estimation of any quantity or quality in scientific or laboratory investigation. 4. Discernment of a state or category ( e.g., in diagnosis). 5. A process, both necessary and sufficient, whereby an effect is caused. [L. de-termino, pp. -atus, to limit, determine, fr. terminus, a boundary]
cell d. the process by which embryonic cells, previously undifferentiated, take on a specific developmental character. See morphogenesis, induction, evocator.
sex d. d. of the sex of a fetus in utero by identification of fetal chromosomes.

determinism
determinism (de-ter′mi-nizm)

The proposition that all behavior is caused exclusively by genetic and environmental influences with no random components, and independent of free will. [L. determino, to limit, fr. terminus, boundary + -ism]
psychic d. in psychoanalysis, the concept that all psychological and behavioral phenomena result from antecedent, unconsciously operating causes.

detersive
detersive (de-ter′siv)

SYN: detergent.

detoxicate
detoxicate (de-tok′si-kat)

To diminish or remove the poisonous quality of any substance; to lessen the virulence of any pathogenic organism. SYN: detoxify. [L. de, from, + toxicum, poison]

detoxication
detoxication (de-tok-si-ka′shun)

SYN: detoxification.
ammonia d. the d. of ammonia and ammonium ion by the formation of ammonium salts, specific nitrogen-excretion products, or l-glutamine.

detoxification
detoxification (de-tok′si-fi-ka′shun)

1. Recovery from the toxic effects of a drug. 2. Removal of the toxic properties from a poison. 3. Metabolic conversion of pharmacologically active principles to pharmacologically less active principles. SYN: detoxication.

detoxify
detoxify (de-tok′si-fi)

SYN: detoxicate.

detrition
detrition (de-trish′un)

A wearing away by use or friction. [L. de-tero, pp. -tritus, to rub off]

detritus
detritus (de-tri′tus)

Any broken-down material, carious or gangrenous matter, gravel, etc. [L. (see detrition)]

detrusor
detrusor (de-troo′ser, -sor)

1. A muscle that has the action of expelling a substance. 2. See d. (muscle). [L. detrudo, to drive away]

detrusorrhaphy
detrusorrhaphy (de-troo′-sor-a-fe)

A procedure in which bladder muscle (detrusor) is reconstructed around the ureterovesical junction to form a competent one-way valve. SEE ALSO: ureteroneocystostomy. SYN: extravesical reimplantation. [detrusor + G. rhaphe, a seam]

detumescence
detumescence (de-too-mes′ens)

Subsidence of a swelling. [L. de, from, + tumesco, to swell up, fr. tumeo, to swell]

deturgescence
deturgescence (de-toor-ges′ens)

The mechanism by which the stroma of the cornea remains relatively dehydrated. [L. de, from, + turgesco, to begin to swell]

deut- deut-

See deutero-.

deutencephalon
deutencephalon (doo′ten-sef′a-lon)

Rarely used term for diencephalon. [G. deuteros, second, + enkephalos, brain]

deuteranomaly
deuteranomaly (doo′ter-a-nom′a-le)

A form of anomalous trichromatism due to a defect of the green-sensitive retinal cones. [G. deuteros, second, + anomalia, anomaly]

deuteranope
deuteranope (doo′ter-a-nop)

A person affected with deuteranopia.

deuteranopia
deuteranopia (doo′ter-a-no′pe-a)

A congenital abnormality of the retina in which there are two rather than three retinal cone pigments (dichromatism) and complete insensitivity to middle wavelengths (green). [G. deuteros, second, + anopia]

deuterio- deuterio-

Prefix indicating “containing deuterium.”

deuterium
deuterium (D) (doo-te-r′e-um)

SYN: hydrogen-2. [G. deuteros, second]
d. oxide SYN: heavy water.

deutero- deutero-, deut-, deuto-

Combining forms meaning two, or second (in a series); secondary. [G. deuteros, second]

deuteromycetes
deuteromycetes (du′ter-o-mi-se′tez)

Members of the class D. or the phylum Deuteromycota.

Deuteromycota
Deuteromycota (doo′ter-o-mi-ko-ta)

A phylum in which the sexual (teleomorph or perfect) part of the life cycle has not been discovered; only the asexual (anamorph or imperfect) part of the life cycle has been found. SEE ALSO: Fungi Imperfecti.

deuteron
deuteron (doo′ter-on)

The nucleus of hydrogen-2, composed of one neutron and one proton; it thus has the one positive charge characteristic of a hydrogen nucleus. SYN: deuton, diplon.

deuteropathic
deuteropathic (doo′ter-o-path′ik)

Relating to a deuteropathy.

deuteropathy
deuteropathy (doo-ter-op′a-the)

A secondary disease or symptom. [deutero- + G. pathos, suffering]

deuteroplasm
deuteroplasm (doo′ter-o-plazm)

SYN: deutoplasm. [deutero- + G. plasma, thing formed]

deuteroporphyrin
deuteroporphyrin (doo′ter-o-por′fi-rin)

A porphyrin derivative resembling the protoporphyrins except that the two vinyl side chains are replaced by hydrogen.

deuterosome
deuterosome (doo′ter-o-som)

Dense spherical fibrous granules that occur in the centrosphere and act in the development of centrioles or basal bodies. SYN: procentriole organizer.

deuterotocia
deuterotocia (doo′ter-o-to′se-a)

A form of parthenogenesis in which the female has offspring of both sexes. SYN: deuterotoky. [deutero- + G. tokos, childbirth]

deuterotoky
deuterotoky (doo-ter-ot′o-ke)

SYN: deuterotocia.

deuto- deuto-

See deutero-.

deutogenic
deutogenic (doo-to-jen′ik)

Of secondary origin following an inductive influence. [deuto- + G. -gen, production]

deutomerite
deutomerite (doo-tom′er-it)

The posterior nucleated portion of an attached cephalont in a gregarine protozoan, separated by an ectoplasmic septum from the anterior portion, or protomerite. [deuto- + L. meros, part]

deuton
deuton (doo′ton)

SYN: deuteron.

deutonymph
deutonymph (doo′to-nimt)

The third stage of a mite.

deutoplasm
deutoplasm (doo′to-plazm)

The yolk of a meroblastic egg; the nonliving material in the cytoplasm, especially that stored in the ovum as food for the developing embryo, the commonest types being lipoid droplets and yolk granules. SYN: deuteroplasm. [deuto- + G. plasma, thing formed]

deutoplasmic
deutoplasmic (doo-to-plaz′mik)

Relating to the deutoplasm.

deutoplasmigenon
deutoplasmigenon (doo′to-plaz-mi-jen′on)

That which produces or gives rise to deutoplasm. [deutoplasm + G. genos, birth]

deutoplasmolysis
deutoplasmolysis (doo′to-plaz-mol′i-sis)

The disintegration of deutoplasm. [deutoplasm + G. lysis, dissolution]

Deutschländer
Deutschländer

Carl E. W., German surgeon, 1872–1942. See D. disease.

DEV
DEV

Abbreviation for duck embryo origin vaccine.

devascularization
devascularization (de-vas′ku-lar-i-za′shun)

Occlusion of all or most of the blood vessels to any part or organ. [L. de, away, + vasculum, small vessel, + G. izo, to cause]

develop
develop (de-vel′op)

To process an exposed photographic or radiographic film in order to turn the latent image into a permanent one. [O.Fr. desveloper, to unwrap, fr. voloper, to wrap]

developer
developer (de-vel′op-er)

1. An individual or procedure that develops. 2. SYN: eluent. 3. The chemicals used to develop film by reducing the light-activated silver halide molecules to atomic silver. 4. The factor(s) causing a cell, organ, or organism to undergo a series of orderly changes.

development
development (de-vel′op-ment)

1. The act or process of natural progression in physical and psychological maturation from a previous, lower, or embryonic stage to a later, more complex, or adult stage. 2. The process of chromatography.
cognitive d. the evolving d. of the infant's and child's intellectual functions.
life-span d. d. and mastery (or loss) of differing biologic, intellectual, behavioral, and social skills in different epochs of the life-span from the prenatal through the gerontological periods of growth.
psychosexual d. maturation and d. of the psychic and behavioral phases of sexuality from birth to adult life through the oral, anal, phallic, latency, and genital phases.

Deventer
Deventer

Hendrik van, Dutch obstetrician, 1651–1724. See D. pelvis.

deviance
deviance (de′ve-ans)

SYN: deviation (3) .

deviant
deviant (de′ve-ant)

1. Denoting or indicative of deviation. 2. An individual exhibiting deviation, especially sexual.

deviation
deviation (de-ve-a′shun)

1. A turning away or aside from the normal point or course. 2. An abnormality. 3. In psychiatry and the behavioral sciences, a departure from an accepted norm, role, or rule. SYN: deviance. 4. A statistical measure representing the difference between an individual value in a set of values and the mean value in that set. [L. devio, to turn from the straight path, fr. de, from, + via, way]
axis d. deflection of the electrical axis of the heart to the right or left of the normal. SEE ALSO: left axis d., right axis d., axis. SYN: axis shift.
conjugate d. of the eyes 1. rotation of the eyes equally and simultaneously in the same direction, as occurs normally; 2. a condition in which both eyes are turned to the same side as a result of either paralysis or muscular spasm.
dissociated horizontal d. a tendency often associated with repaired congenital esotropia in which an eye abducts when it is covered, in violation of Herring law.
dissociated vertical d. a tendency often associated with congenital esotropia, in which an eye elevates, abducts, and extorts when covered, in violation of Herring law.
immune d. SYN: split tolerance.
d. to the left SYN: shift to the left (1) .
left axis d. a mean electrical axis of the heart pointing to −30° or more negative. See hexaxial reference system.
primary d. the ocular d. seen in paralysis of an ocular muscle when the nonparalyzed eye is used for fixation.
d. to the right SYN: shift to the right (1) .
right axis d. a mean electrical axis of the heart pointing to the right of +90°. See hexaxial reference system.
secondary d. ocular d. seen in paralysis of an ocular muscle when the paralyzed eye is used for fixation.
sexual d. a sexual practice that is biologically atypical, considered morally wrong, or legally prohibited. See bestiality, pedophilia. SYN: sexual perversion.
skew d. a hypertropia in which the eyes move in opposite directions equally; an acquired hypertropia, often fairly comitant, not fitting the characteristic pattern of trochlear nerve damage or of ocular muscle abnormality; often due to a brainstem or cerebellar lesion.
standard d. (SD, σ) 1. statistical index of the degree of d. from central tendency, namely, of the variability within a distribution; the square root of the average of the squared deviations from the mean. 2. a measure of dispersion or variation used to describe a characteristic of a frequency distribution.

Devic
Devic

Eugène, French physician, 1869–1930. See D. disease.

device
device (de-vis′)

An appliance, usually mechanical, designed to perform a specific function, such as prosthesis or orthesis. [M.E., fr. O.Fr. devis, fr. L. divisum, divided]
central-bearing d. in dentistry, a d. which provides a central point of bearing, or support, between upper and lower record bases; it consists of a contacting point which is attached to one base and a plate attached to the other which provides the surface on which the bearing point rests or moves.
central-bearing tracing d. in dentistry, a central-bearing d. used for making a tracing and/or for support between upper and lower bases.
contraceptive d. a d. used to prevent pregnancy; e.g., occlusive diaphragm, condom, intrauterine d..
intrauterine devices (IUD) pieces of plastic or metal of various shapes ( e.g., coil, loop, bow “T”) inserted into the uterus to exert a contraceptive effect. SYN: intrauterine contraceptive devices.
intrauterine contraceptive devices (IUCD) SYN: intrauterine devices.
left-ventricular assist d. mechanical pump inserted at some point in the circulation to parallel the activity of the left ventricle and thereby reduce its load.
ventricular assist d. any of a variety of mechanical devices that support or replace the pumping function of the left (LVAD) or right ventricle (RVAD). The inflow end of the pump is connected to the ventricle and the outflow end to the aorta (LVAD) or pulmonary artery (RVAD). Most or all of the cardiac output is directed through the d. to allow time for recovery of the patient's damaged heart muscle after myocardial infraction or heart surgery. Also used as “a bridge to transplantation,” i.e., to maintain the patient whose heart will not recover until a donor heart becomes available.

deviometer
deviometer (de-ve-om′e-ter)

A form of strabismometer.

devitalization
devitalization (de-vi′tal-i-za′shun)

1. Deprivation of vitality or of vital properties. 2. In dentistry, the process by which tooth pulp is destroyed; e.g., by chemical means, by infection, or by extirpation.

devitalize
devitalize (de-vi′tal-iz)

To deprive of vitality or of vital properties.

devitalized
devitalized (de-vi′tal-izd)

Devoid of life; dead.

devolution
devolution (dev-o-loo′shun)

A continuing process of degeneration or breaking down, in contrast to evolution. SEE ALSO: involution, catabolism. [L. de-volvo, pp. -volutus, to roll down]

Dewar
Dewar

Sir James, English chemist, 1842–1923. See D. flask.

de Wecker
de Wecker

Louis H., French physician, 1832–1906. See de Wecker scissors.

dexamethasone
dexamethasone (dek-sa-meth′a-son)

A potent synthetic analogue of cortisol, with similar biological action; used as an anti-inflammatory agent and as a test material for adrenal cortical function.

dexamphetamine
dexamphetamine (deks-am-fet′a-men)

SYN: dextroamphetamine sulfate.
d. sodium phosphate the water-soluble ester of d., with the same actions and uses.

dexbrompheniramine maleate
dexbrompheniramine maleate (deks′brom-fen-ir′a-men)

The dextrorotatory isomer of brompheniramine; an antihistamine.

dexchlorpheniramine maleate
dexchlorpheniramine maleate (deks′klor-fen-ir′a-men)

The dextrorotatory isomer of chlorpheniramine; an antihistamine.

dexiocardia
dexiocardia (deks-e-o-kar′de-a)

SYN: dextrocardia.

dexpanthenol
dexpanthenol (deks-pan′the-nol)

Pantothenic acid with –CH₂OH replacing the terminal –COOH; a cholinergic agent and a dietary source of pantothenic acid. SYN: panthenol, pantothenyl alcohol.

dexter
dexter (D) (deks′ter)

Located on or relating to the right side. [L. fr. dextra, neut. dextrum]

dextr- dextr-

See dextro-.

dextrad
dextrad (deks′trad)

Toward the right side. [L. dexter, right, + ad, to]

dextral
dextral (deks′tral)

SYN: right-handed.

dextrality
dextrality (deks-tral′i-te)

Right-handedness; preference for the right hand in performing manual tasks.

dextran
dextran (deks′tran)

1. Any of several water-soluble high molecular weight glucose polymers (average MW 75,000; ranging between 1,000 and 40,000,000) produced by the action of members of the family Lactobacillaceae and certain other microorganisms on sucrose; used in isotonic sodium chloride solution for the treatment of shock, and in distilled water for the relief of the edema of nephrosis; lower molecular weight d. ( e.g., MW 40,000) improves blood flow in areas of stasis by reducing cellular aggregation. 2. Poly(α-1,6-glucose);α-1,6-glucan with branch points (1,2; 1,3; 1,4) and spacing of these characteristic of the species; used as plasma substitutes or expanders. See dextransucrase.
d. 110 d. (average MW 110,000) available as 5% solution in water or saline solution; used as a plasma volume expander.
d. 40 d. (average MW 40,000) used as a plasma volume expander and blood flow adjuvant.
d. 70 d. (average MW 70,000) used as a plasma volume expander.
d. 75 d. (average MW 75,000) used as a plasma volume expander.
acid d. the product of acid and heat treatment of d..
animal d. SYN: glycogen.
blue d. high molecular weight d. containing a blue chlorotriazine dye, Cibacron Blue; used to measure the void volumes in gel filtration columns, as well as checking column packing.
d. sulfate the sodium salt of sulfuric acid esters of the polysaccharide d.; it contains not less than 10 units per mg and not less than 14% of sulfate; an anticoagulant.

dextranase
dextranase (deks′tran-as)

An enzyme hydrolyzing α-1,6-d-glucosidic linkages in dextran; used in the prevention of caries.

dextransucrase
dextransucrase (deks-tran-su′kras)

A glucosyltransferase that builds poly(α-1,6-d-glucosyl), i.e., polyglucoses, dextrans, or α-glucans, from sucrose, releasing d-fructose residues.

dextrase
dextrase (deks′tras)

Nonspecific term for the complex of enzymes that converts dextrose (d-glucose) into lactic acid.

dextriferron
dextriferron (deks-tri-fer′on)

A colloidal solution of ferric hydroxide in complex with partially hydrolyzed dextrin, used in the treatment of iron-deficiency anemia; it is suitable for intravenous administration and contains 20 mg of iron per ml.

dextrin
dextrin (deks′trin)

A mixture of oligo(α-1,4-d-glucose) molecules formed during the enzymic or acid hydrolysis of starch, amylopectin, or glycogen; on further hydrolysis they are converted into d-glucose. Dextrins are of much lower molecular weight than dextrans, hence are not suitable as plasma expanders; d. (usually white d.) is used in pharmaceutical preparations. SYN: starch gum.
acid d. the product of acid and heat treatment of d..
limit d. the polysaccharide fragments remaining at the end (limit) of exhaustive hydrolysis of amylopectin or glycogen by α-1,4-glucan maltohydrolase or β-amylase, which cannot hydrolyze the α-1,6 bonds at branch points; accumulates in individuals with type III glycogen storage disease. SYN: d. limit.
Schardinger dextrins cyclic rings of glucose monomer (usually 6 to 8) linked α-1,4; the result of action of Bacillus macerans on starch.

dextrinase
dextrinase (deks′tri-nas)

Any of the enzymes catalyzing the hydrolysis of dextrins; e.g., amylo-1,6-glucosidase, dextrin dextranase.
limit d. 1. SYN: α-dextrin endo-1,6-α-glucosidase. 2. SYN: oligo-α-1,6-glucosidase.

dextrin dextranase
dextrin dextranase

A glucosyltransferase transferring 1,4-α-d-glucosyl residues, thus catalyzing the synthesis of dextrans (with 1,6 links between monosaccharide units) from dextrins (with 1,4 links) by glucose transfer. SYN: dextrin → dextran transglucosidase, dextrin 6-glucosyltransferase.

dextrin → dextran transglucosidase
dextrin → dextran transglucosidase

SYN: dextrin dextranase.

dextrin 6-α-d-glucosidase
dextrin 6-α-d-glucosidase

SYN: amylo-1,6-glucosidase.

dextrin 6-glucosyltransferase
dextrin 6-glucosyltransferase

SYN: dextrin dextranase.

dextrin glycosyltransferase
dextrin glycosyltransferase

SYN: 4-α-d-glucanotransferase.

dextrin limit
dextrin limit

SYN: limit dextrin.

dextrinogenic
dextrinogenic (deks′trin-o-jen′ik)

Capable of producing dextrin.

dextrinosis
dextrinosis (deks-trin-o′sis)

SYN: glycogenosis.
debranching deficiency limit d., limit d. SYN: type 3 glycogenosis.

dextrin transglycosylase
dextrin transglycosylase

SYN: 4-α-d-glucanotransferase.

dextrinuria
dextrinuria (deks-tri-noo′re-a)

The passage of dextrin in the urine.

dextro- dextro-, dextr-

1. Prefixes meaning right, toward, or on the right side. 2. Chemical prefixes meaning dextrorotatory. [L. dexter, on the right-hand side]

dextroamphetamine phosphate
dextroamphetamine phosphate (deks′tro-am-fet′a-men)

Same actions and uses as dextroamphetamine sulfate. SYN: d-amphetamine phosphate.

dextroamphetamine sulfate
dextroamphetamine sulfate

Similar in action to racemic amphetamine sulfate, but is more stimulating to the central nervous system; sympathomimetic and appetite depressant. SYN: d-amphetamine sulfate, dexamphetamine.

dextrocardia
dextrocardia (deks′tro-kar′de-a)

Displacement of the heart to the right, either as dextroposition, with simple displacement to the right, or as cardiac heterotaxia, with complete transposition of the right and left chambers, resulting in a heart that is the mirror image of a normal heart. SYN: dexiocardia. [dextro- + G. kardia, heart]
corrected d. displacement and rotation of the heart into the right side of the chest but without mirror transposition of the cardiac chambers. SYN: dextroversion of the heart, false d., type 3 d..
false d. SYN: corrected d..
isolated d. d. with mirror-image transposition of the cardiac chambers but without displacement of the abdominal viscera. SYN: type 2 d..
mirror image d. perfect right to left congenital reversal of the heart sometimes with other congenital abnormalities, sometimes normal except for position.
secondary d. dextroposition of the heart by some disease of the lungs, pleura, or diaphragm. SYN: type 4 d..
type 1 d. SYN: d. with situs inversus.
type 2 d. SYN: isolated d..
type 3 d. SYN: corrected d..
type 4 d. SYN: secondary d..
d. with situs inversus displacement of the heart to the right side of the chest with mirror-image transposition of the cardiac chambers together with transposition of the abdominal viscera. SYN: type 1 d..

dextrocardiogram
dextrocardiogram (deks′tro-kar′de-o-gram)

That part of the electrocardiogram that is derived from the right ventricle.

dextrocerebral
dextrocerebral (deks′tro-ser′e-bral)

Having a dominant right cerebral hemisphere.

dextrocular
dextrocular (deks-trok′u-lar)

Rarely used term for indicating right ocular dominance; denoting one who prefers the right eye in monocular work, such as microscopy. SYN: right-eyed. [dextro- + L. oculus, eye]

dextrocycloduction
dextrocycloduction (deks′tro-si-klo-duk′shun)

Rotation of the upper pole of the cornea to the right. See excycloduction. [dextro- + cyclo- + L. duco, pp. ductus, to lead]

dextroduction
dextroduction (deks-tro-duk′shun)

Rarely used term for rotation of one eye to the right. [dextro- + L. duco, pp. ductus, to lead]

dextrogastria
dextrogastria (deks-tro-gas′tre-a)

Condition in which the stomach is displaced to the right; may represent either simple displacement or situs inversus. Usually associated with dextrocardia. [dextro- + G. gaster, stomach]

dextroglucose
dextroglucose (deks-tro-gloo′kos)

See d-glucose.

dextrogram
dextrogram (deks′tro-gram)

Electrocardiographic record in an experimental animal representing spread of impulse through the right ventricle alone.

dextrogyration
dextrogyration (deks′tro-ji-ra′shun)

A twisting to the right. [dextro- + L. gyro, pp. -atus, to turn in a circle, fr. gyrus, circle]

dextromanual
dextromanual (deks-tro-man′u-al)

SYN: right-handed. [dextro- + L. manus, hand]

dextromethorphan hydrobromide
dextromethorphan hydrobromide (deks′tro-meth-or′fan hi-dro-bro′mid)

A synthetic morphine derivative used as an antitussive agent. Inferior to codeine but seemingly lacking in dependence production. It has weak central depressant action.

dextromoramide tartrate
dextromoramide tartrate (deks-tro-mor′a-mid)

A narcotic analgesic related chemically and pharmacologically to methadone.

dextropedal
dextropedal (deks-trop′e-dal)

Denoting one who uses the right leg in preference to the left. SYN: right-footed. [dextro- + L. pes (ped-), foot]

dextroposition
dextroposition (deks′tro-po-zi′shun)

Abnormal right-sided location or origin of a normally left-sided structure, e.g., origin of the aorta from the right ventricle.
d. of the heart dextrocardia.

dextropropoxyphene hydrochloride
dextropropoxyphene hydrochloride (deks′tro-pro-pok′se-fen)

SYN: propoxyphene hydrochloride.

dextropropoxyphene napsylate
dextropropoxyphene napsylate

SYN: propoxyphene napsylate.

dextrorotation
dextrorotation (deks′tro-ro-ta′shun)

A turning or twisting to the right; especially, the clockwise twist given the plane of plane-polarized light by solutions of certain optically active substances. Cf.:levorotation.

dextrorotatory
dextrorotatory (deks-tro-ro′ta-tor-e)

Denoting dextrorotation, or certain crystals or solutions capable of such action; as a chemical prefix, usually abbreviated d-. Cf.:levorotatory.

dextrose
dextrose (deks′tros)

See d-glucose.

dextrosinistral
dextrosinistral (deks′tro-si-nis′tral)

In a direction from right to left. [dextro- + L. sinister, left]

dextrothyroxine sodium
dextrothyroxine sodium (deks-tro-thi-roks′en)

An antihypercholesterolemic agent.

dextrotorsion
dextrotorsion (deks-tro-tor′shun)

1. A twisting to the right. 2. In ophthalmology, a seldom-used term for a conjugate rotation of the upper pole of both corneas to the right. [dextro- + L. torsio, a twisting]

dextrotropic
dextrotropic (dek-tro-trop′ik)

Turning to the right. [dextro- + G. tropos, a turn]

dextroversion
dextroversion (deks′tro-ver′zhun)

1. Version toward the right. 2. In ophthalmology, a conjugate rotation of both eyes to the right. [dextro- + L. verto, pp. versus, to turn]
d. of the heart SYN: corrected dextrocardia.

d.f.
d.f.

Abbreviation for degrees of freedom, under degree.

df
df, DF

Abbreviation for decayed and filled teeth. SYN: d. caries index.

DFP
DFP

Abbreviation for diisopropyl fluorophosphate.

dGlc
dGlc

Abbreviation for 2-deoxyglucose.

dGMP
dGMP

Abbreviation for deoxyguanylic acid.

DHAP
DHAP

Abbreviation for dihydroxyacetone phosphate.

Dharmendra antigen
Dharmendra antigen

See under antigen.

DHEA
DHEA

Abbreviation for dehydro-3-epiandrosterone.

DHEA
DHEA

Abbreviation for dehydroepiandrosterone.

DHEAS
DHEAS

Abbreviation for the sulfate salt of dehydroepiandrosterone.

d'Herelle
d'Herelle

Felix H., Canadian physician and bacteriologist, 1873–1949. See d'Herelle phenomenon, Twort-d'Herelle phenomenon.

DHF
DHF

Abbreviation for dihydrofolic acid.

DHFR
DHFR

Abbreviation for dihydrofolate reductase.

D. Hy.
D. Hy.

Abbreviation for Doctor of Hygiene.

DI
DI

Abbreviation for dental index.

di- di-

1. Two, twice. 2. In chemistry, often used in place of bis- when not likely to be confusing; e.g., dichloro- compounds. Cf.:bi-, bis-. [G. dis, two]

dia- dia-

Through, throughout, completely. [G. dia, through]

diabetes
diabetes (di-a-be′tez)

Either d. insipidus or d. mellitus, diseases having in common the symptom polyuria; when used without qualification, refers to d. mellitus. [G. d., a compass, a siphon, d.]
adult-onset d. non-insulin-dependent d. mellitus.
alimentary d. SYN: alimentary glycosuria.
alloxan d. experimental d. mellitus produced in animals by the administration of alloxan, which damages the insulin-producing islet cells of the pancreas.
brittle d. d. mellitus in which there are marked fluctuations in blood glucose concentrations that are difficult to control.
bronze d. d. mellitus associated with hemochromatosis, with iron deposits in the skin, liver, pancreas, and other viscera, often with severe liver damage and glycosuria. SEE ALSO: hemochromatosis. SYN: bronzed d., bronzed disease.
bronzed d. SYN: bronze d..
calcinuric d. SYN: hypercalciuria.
chemical d. SYN: latent d..
galactose d. SYN: galactosemia.
gestational d. carbohydrate intolerance of variable severity with onset or first recognition during pregnancy.Gestational d. occurs in 3–6% of all pregnancies, and although it typically resolves after delivery, as many as 60% of women with this disorder eventually develop type 2 d.. D. occurring during pregnancy increases the risk of maternal pyelonephritis and of certain congenital anomalies, and is often associated with polyhydramnios and fetal macrosomia, with resultant dystocia. It is recommended that all pregnant women be screened for gestational d. between the 24th and 28th week of pregnancy by determination of the plasma glucose level 1 hour after a 50 g oral glucose load. A level above 140 mg/dL (7.8 mmol/L) is an indication for a 3-hour glucose tolerance test. Gestational d. can usually be managed by diet alone, but insulin is sometimes required.
growth-onset d. SYN: insulin-dependent d. mellitus.
d. innocens obsolete term for renal glycosuria.
d. insipidus chronic excretion of very large amounts of pale urine of low specific gravity, causing dehydration and extreme thirst; ordinarily results from inadequate output of pituitary antidiuretic hormone; the urine abnormalities may be mimicked as a result of excessive fluid intake, as in psychogenic polydipsia. Several types exist: central, neurohypophyseal, and nephrogenic. Autosomal dominant [MIM*125700, *125800, *192340], X-linked [MIM*304800 and *304900], and even autosomal recessive forms [MIM*222000] have been described. SEE ALSO: nephrogenic d. insipidus.
insulin-dependent d. mellitus (IDDM) severe d. mellitus, often brittle, usually of abrupt onset during the first two decades of life but can develop at any age; characterized by polydipsia, polyuria, increased appetite, weight loss, low plasma insulin levels, and susceptibility to ketoacidosis; immune-mediated destruction of pancreatic B cells; insulin therapy and dietary regulation are necessary. Term declared obsolete by American D. Association. SYN: growth-onset d., juvenile-onset d., type I d..
insulinopenic d. any form of d. mellitus resulting from inadequate secretion of insulin.
d. intermittens d. mellitus in which there are periods of relatively normal carbohydrate metabolism followed by relapses to the previous diabetic state.
juvenile d. d. mellitus appearing in a child or adolescent; often fatal before the discovery of insulin, usually of abrupt onset during first or second decades of life; characterized by polyuria, polydipsia, weight loss; usually severe, insulin dependent, and prone to periods of ketoacidosis; can be familial, follow a viral infection such as mumps; thought to be due to virus-induced or immune destruction of pancreatic islets. SYN: type I d. mellitus.
juvenile-onset d. SYN: insulin-dependent d. mellitus.
ketosis-prone d. type I or juvenile d. mellitus, in which inadequate treatment leads to development of ketoacidosis.
ketosis-resistant d. type II or adult onset d. mellitus, in which episodes of ketoacidosis rarely occur.
latent d. a mild form of d. mellitus in which the patient displays no overt symptoms, but displays certain abnormal responses to diagnostic procedures, such as an elevated fasting blood glucose concentration or reduced glucose tolerance. Term declared obsolete by American D. Association. SYN: chemical d..
lipoatrophic d. SYN: lipoatrophy.
lipogenous d. d. and obesity combined.
maturity-onset d. non-insulin-dependent d. mellitus.
maturity onset d. of youth a relatively mild, non-insulin requiring form of d. mellitus beginning at a younger age than usual.
d. mellitus (DM) a chronic metabolic disorder in which utilization of carbohydrate is impaired and that of lipid and protein enhanced; it is caused by an absolute or relative deficiency of insulin and is characterized, in more severe cases, by chronic hyperglycemia, glycosuria, water and electrolyte loss, ketoacidosis, and coma; long-term complications include neuropathy, retinopathy, nephropathy, generalized degenerative changes in large and small blood vessels, and increased susceptibility to infection. [L. sweetened with honey] D. mellitus affects at least 16 million Americans, ranks seventh as a cause of death in the United States, and costs the national economy over $100 billion yearly. About 95% of persons with DM have type 2, in which the pancreatic beta cells retain some insulin-producing potential, and the rest have type 1, in which exogenous insulin is required for long-term survival. In type 1 DM, which typically causes symptoms before age 25, an autoimmune process is responsible for beta cell destruction. Type 2 DM is characterized by insulin resistance in peripheral tissues as well as a defect in insulin secretion by beta cells. Insulin regulates carbohydrate metabolism by mediating the rapid transport of glucose and amino acids from the circulation into muscle and other tissue cells, by promoting the storage of glucose in liver cells as glycogen, and by inhibiting gluconeogenesis. The normal stimulus for the release of insulin from the pancreas is a rise in the concentration of glucose in circulating blood, which typically occurs within a few minutes after a meal. When such a rise elicits an appropriate insulin response, so that the blood level of glucose falls again as it is taken into cells, glucose tolerance is said to be normal. The central fact in d. mellitus is an impairment of glucose tolerance of such a degree as to threaten or impair health. Revised diagnostic criteria for DM were published by the American D. Association in June 1997. All criteria depend on the glucose concentration of venous plasma. The diagnosis is confirmed when any 2 tests performed on different days yield levels at or above established thresholds: in the fasting state, 126 mg/dL (7.0 mmol/L); 2 hours postprandially (after a 75-g glucose load), or at random, 200 mg/dL (11.1 mmol/L). Long recognized as an independent risk factor for cardiovascular disease, DM is often associated with other risk factors, including disorders of lipid metabolism, obesity, hypertension, and impairment of renal function. Current recommendations for the management of DM emphasize education and individualization of therapy. Controlled studies have shown that rigorous maintenance of plasma glucose levels as near to normal as possible at all times substantially reduces the incidence and severity of long-term complications, particularly microvascular complications (retinopathy, neuropathy, and nephropathy). Such control involves limitation of dietary carbohydrate and saturated fat; monitoring of blood glucose, including self-testing by the patient and periodic determination of glycosylated hemoglobin; and administration of insulin (particularly in type 1 DM), drugs that stimulate endogenous insulin production (in type 2 DM), or both. Some studies suggest that the risk of cardiovascular disease may be increased in some patients by intensive treatment of DM because of elevation of body weight, blood pressure, triglycerides, and total and low-density cholesterol. Pharmaceutical agents developed during the 1990s have improved control of DM by enhancing responsiveness of cells to insulin, counteracting insulin resistance, and reducing postprandial carbohydrate absorption. See Also insulin resistance; alpha-reductase inhibitor.
metahypophysial d. 1. d. mellitus caused by large quantities of endogenous or exogenous pituitary growth hormone; 2. term used to designate the irreversible phase of d. mellitus in acromegaly.
Mosler d. inosituria with excretion of large quantities of water.
nephrogenic d. insipidus [MIM*304800] d. insipidus due to inability of the kidney tubules to respond to antidiuretic hormone; X-linked inheritance, caused by mutation in the vasopressin V2 receptor gene (AVPR2) on Xq. There is also an autosomal dominant form [MIM*125800], caused by mutation in the aquaphorin 2 gene (AQP2) on 12q. SYN: vasopressin-resistant d..
non-insulin-dependent d. mellitus (NIDDM) an often mild form of d. mellitus of gradual onset, usually in obese individuals over age 35; absolute plasma insulin levels are normal to high, but relatively low in relation to plasma glucose levels; ketoacidosis is rare, but hyperosmolar coma can occur; responds well to dietary regulation and/or oral hypoglycemic agents, but diabetic complications and degenerative changes can develop. Term declared obsolete by American D. Association.
pancreatic d. 1. d. mellitus demonstrably dependent upon a pancreatic lesion; 2. d. following removal of the pancreas in an animal.
phlorizin d. (flo-rid′zin) SYN: phlorizin glycosuria.
phosphate d. excessive secretion of phosphate in the urine due to a defect in tubular reabsorption; usually part of a more generalized abnormality, such as Fanconi syndrome.
piqûre d. SYN: puncture d.. [Fr.]
pregnancy d. subclinical d..
puncture d. experimental d. produced in animals by puncture of the floor of the fourth ventricle of the brain. SYN: piqûre d..
renal d. SYN: renal glycosuria.
starvation d. after prolonged fasting, glycosuria following the ingestion of carbohydrate or glucose because of reduced output of insulin and/or reduced rate of glucose metabolism with a reduced ability to form glycogen.
steroid d. d. mellitus produced by pharmacological doses of steroid hormones, particularly glucocorticoids or estrogens; characterized by one or more of the typical manifestations of d. mellitus.
steroidogenic d. abnormal glucose tolerance, often frank d. mellitus, induced by the metabolic effects of adrenocortical steroid hormones such as cortisone or therapeutic analogues such as prednisone. The effect may be temporary, resolving when the steroid therapy is discontinued, or d. mellitus may persist.
subclinical d. a form of d. mellitus that is clinically evident only under certain circumstances, such as pregnancy or extreme stress; persons so afflicted may, in time, manifest more severe forms of the disease. Term declared obsolete by American D. Association.
thiazide d. impaired carbohydrate metabolism associated with the use of thiazide diuretic drugs; severe manifestations are seen in persons having d. mellitus, but impairment is mild or absent in nondiabetic individuals.
type I d. SYN: insulin-dependent d. mellitus.
type II d. non-insulin-dependent d. mellitus.
type I d. mellitus SYN: juvenile d..
vasopressin-resistant d. SYN: nephrogenic d. insipidus.

diabetic
diabetic (di-a-bet′ik)

1. Relating to or suffering from diabetes. 2. One who suffers from diabetes.

diabetogenic
diabetogenic (di′a-bet-o-jen′ik, -be-to-jen′ik)

Causing diabetes.

diabetogenous
diabetogenous (di′a-be-toj′en-us)

Caused by diabetes.

diabetology
diabetology (di′a-be-tol′o-je)

The field of medicine concerned with diabetes.

diacele
diacele (di′a-sel)

Rarely used term for third ventricle. [G. dia-, through, + koilia, a hollow]

diacetal
diacetal (di-as′e-tal)

See diacetyl.

diacetate
diacetate (di-as′e-tat)

1. SYN: acetoacetate. 2. A compound containing two acetate residues.

diacetemia
diacetemia (di-as-e-te′me-a)

A form of acidosis resulting from the presence of acetoacetic (diacetic) acid in the blood.

diacetonuria
diacetonuria (di-as′e-to-noo′re-a)

SYN: diaceturia.

diaceturia
diaceturia (di-as-e-too′re-a)

The urinary excretion of acetoacetic (diacetic) acid. SYN: diacetonuria.

diacetyl
diacetyl, diacetal (di-as′e-til, di-as′e-tal)

A yellow liquid, (CH₃CO)₂, having the pungent odor of quinone and carrying the aromas of coffee, vinegar, butter, and other foods; a byproduct of carbohydrate degradation.

diacetylcholine
diacetylcholine (di-as′e-til-ko′len)

SYN: succinylcholine.

diacetylmonoxime
diacetylmonoxime (DAM) (di-as′e-til-mon-ok′sim)

A 2-oxo-oxime that can reactivate phosphorylated acetylcholinesterase in vitro and in vivo; it penetrates the blood-brain barrier. SImilar to 2-PAM.

diacetylmorphine
diacetylmorphine (di-as′e-til-mor′fen)

SYN: heroin.

diacetyltannic acid
diacetyltannic acid (di-as′e-til-tan′ik)

SYN: acetyltannic acid.

diachronic
diachronic (di-a-kron′ik)

Systematically observed over time in the same subjects throughout as opposed to synchronic or cross-sectional; the inferences are equivalent only where there is strict stability of all elements. [dia- + G. chronos, time]

diacid
diacid (di-as′id)

Denoting a substance containing two ionizable hydrogen atoms per molecule; more generally, a base capable of combining with two hydrogen ions per molecule.

diaclasis
diaclasis, diaclasia (di-ak′la-sis, di-a-kla′ze-a)

SYN: osteoclasis. [G. diaklasis, a breaking up, fr. dia, through, + klasis, a breaking]

diacrinous
diacrinous (di-ak′ri-nus)

Excreting by simple passage through a gland cell. [G. diakrino, to separate one from another]

diacrisis
diacrisis (di-ak′ri-sis)

SYN: diagnosis. [G. dia-, through, + krisis, a judgment]

diacritic
diacritic, diacritical (di-a-krit′ik, -krit′i-kal)

Distinguishing; diagnostic; allowing of distinction. [G. diakritikos, able to distinguish]

diactinic
diactinic (di′ak-tin′ik)

Having the property of transmitting light capable of bringing about chemical reactions. [G. dia, through, + aktis, ray]

diacylglycerol
diacylglycerol (DAG) (di′as-il-glis′er-ol)

Diglyceride; glycerol with two esterified acyl moieties, either 1,3-d. or 1,2-d.; if the two acyl groups are nonidentical, there are four possible stereoisomers; 1,2-d. is an intermediate in the synthesis of triacylglycerols and of lecithin; also serves as a second messenger in stimulating the activity of protein kinase C.
d. acyltransferase an enzyme, in fat biosynthesis, that catalyzes the transfer of an acyl moiety from acyl-CoA to 1,2-d. thus forming free coenzyme A and triacylglycerol.
d. lipase SYN: lipoprotein lipase.

diad
diad (di′ad)

1. The transverse tubule and a cisterna in cardiac muscle fibers. 2. SYN: dyad (1) .

diadochocinesia
diadochocinesia (di-ad′o-ko-si-ne′ze-a)

SYN: diadochokinesia.

diadochokinesia
diadochokinesia, diadochokinesis (di-ad′o-ko-ki-ne′ze-a, -ki-ne′sis)

The normal power of alternately bringing a limb into opposite positions, as of flexion and extention or of pronation and supination. SYN: diadochocinesia. [G. diadochos, working in turn, + kinesis, movement]

diadochokinetic
diadochokinetic (di-ad′o-ko-ki-net′ik)

Relating to diadochokinesia.

diagnose
diagnose (di-ag-nos′)

To make a diagnosis.

diagnosis
diagnosis (di-ag-no′sis)

The determination of the nature of a disease, injury, or congenital defect. SYN: diacrisis. [G. d., a deciding]
antenatal d. SYN: prenatal d..
clinical d. a d. made from a study of the signs and symptoms of a disease.
differential d. the determination of which of two or more diseases with similar symptoms is the one from which the patient is suffering, by a systematic comparison and contrasting of the clinical findings. SYN: differentiation (2) .
d. by exclusion a d. made by excluding those diseases to which only some of the patient's symptoms might belong, leaving one disease as the most likely d., although no definitive tests or findings establish that d..
laboratory d. a d. made by a chemical, microscopic, microbiologic, immunologic, or pathologic study of secretions, discharges, blood, or tissue.
neonatal d. systematic evaluation of the newborn for evidence of disease or malformations, and the conclusion reached.
pathologic d. a d., sometimes postmortem, made from an anatomic and/or histologic study of the lesions present.
physical d. 1. a d. made by means of physical examination of the patient. 2. the process of a physical examination.
prenatal d. d. utilizing procedures available for the recognition of diseases and malformations in utero, and the conclusion reached. SYN: antenatal d..

diagnostic
diagnostic (di-ag-nos′tik)

1. Relating to or aiding in diagnosis. 2. Establishing or confirming a diagnosis.

diagnostician
diagnostician (di′ag-nos-tish′an)

One who is skilled in making diagnoses; formerly, a name for specialists in internal medicine.

Diagnostic and Statistical Manual of Mental Disorders Diagnostic and Statistical Manual of Mental Disorders (DSM)

A system of classification, published by the American Psychiatric Association, that divides recognized mental disorders into clearly defined categories based on sets of objective criteria. Representing a majority view (rather than a consensus) of hundreds of contributors and consultants, DSM is widely recognized as a diagnostic standard and widely used for reporting, coding, and statistical purposes.The first edition (1952), based on the sixth revision of the International Classification of Diseases (ICD-6), was intended to promote uniformity in the naming and reporting of psychiatric disorders. It contained definitions of all named disorders, but no sets of diagnostic criteria. While its classification of mental disorders showed the influence of Freudian psychoanalysis, its nomenclature (e.g., depressive reaction, anxiety reaction, schizophrenic reaction) reflected the theories of Adolf Meyer (1866–1950). The second edition (DSM-II, 1968) preserved the psychoanalytic orientation but dropped the “reaction” terminology. The third edition (DSM-III, 1980) abandoned much of the rigidly psychodynamic thinking of the earlier editions and, for the first time, provided explicit diagnostic criteria and introduced a multiaxial system whereby different aspects of a patient's condition could be separately assessed. Briefly stated, the axes are I, clinical disorders; II, personality disorders and mental retardation; III, general medical disorders; IV, psychosocial and environmental stressors; and V, overall level of functioning. A revised version of the third edition (DSM-IIIR, 1987) incorporated a number of improvements and clarifications. The fourth edition (DSM-IV) appeared in May, 1994. It follows its two predecessors closely in general outline, and like them is coordinated with and partly derived from ICD-9. For many observers, the most significant change in DSM-IV is the renaming of the category formerly called “Organic Mental Syndromes and Disorders” as “Delirium, Dementia, and Amnestic and Other Cognitive Disorders,” a shift in terminology intended to avoid the implication that mental disorders in other categories are not organic.

diagram
diagram

A simple, graphic depiction of an idea or object.
Dieuaide d. SYN: triaxial reference system.
flow d. a d. composed of blocks connected by arrows representing steps in a process such as decision analysis.
Venn d. pictorial representation of the extent to which two or more quantities or concepts are mutually inclusive and exclusive.

diakinesis
diakinesis (di′a-ki-ne′sis)

Final stage of prophase in meiosis I, in which the chiasmata present during the diplotene stage disappear, the chromosomes continue to shorten, and the nucleolus and nuclear membrane disappear. [G. dia, through, + kinesis, movement]

dial
dial (di′al, dil)

A clock face or instrument resembling a clock face. [L. dies, day]
astigmatic d. a diagram of radiating lines, used to test for astigmatism.

Dialister
Dialister (di-al-is′ter)

An obsolete name for a genus of bacteria, the type species of which, D. pneumosintes, is now placed in the genus Bacteroides.

diallyl
diallyl (di-al′il)

A compound containing two allyl groups.

dialysance
dialysance (di-al′i-sans)

The number of milliliters of blood completely cleared of any substance by an artificial kidney or by peritoneal dialysis in a unit of time; conventional clearance formulas are expressed as mm/min. [fr. dialysis]

dialysate
dialysate (di-al′i-sat)

That part of a mixture that passes through a dialyzing membrane; the material that does not pass through is referred to as the retentate. SYN: diffusate.

dialysis
dialysis (di-al′i-sis)

1. A form of filtration to separate crystalloid from colloid substances (or smaller molecules from larger ones) in a solution by interposing a semipermeable membrane between the solution and dialyzing fluid; the crystalloid (smaller) substances pass through the membrane into the dialyzing fluid on the other side, the colloids do not. 2. The separation of substances across a semipermeable membrane on the basis of particle size and/or concentration gradients. 3. A method of artificial kidney function. [G. a separation, fr. dialyo, to separate]
continuous ambulatory peritoneal d. (CAPD) method of peritoneal d. performed in ambulatory patients with influx and efflux of dialysate during normal activities.
equilibrium d. in immunology, a method for determination of association constants for hapten-antibody reactions in a system in which the hapten (dialyzable) and antibody (nondialyzable) solutions are separated by semipermeable membranes. Since at equilibrium the quantity of free hapten will be the same in the two compartments, quantitative determinations can be made of hapten-bound antibody, free antibody, and free hapten.
extracorporeal d. hemodialysis performed through an apparatus outside the body.
peritoneal d. removal from the body of soluble substances and water by transfer across the peritoneum, utilizing a d. solution which is intermittently introduced into and removed from the peritoneal cavity; transfer of diffusable solutes and water between the blood and the peritoneal cavity depends on the concentration gradient between the two fluid compartments.
d. retinae congenital or traumatic separation of the peripheral sensory retina from the retinal pigment epithelium at the ora serrata, often causing a retinal detachment. SYN: retinodialysis.

dialyze
dialyze (di′a-liz)

To perform dialysis; to separate a substance from a solution by means of dialysis.

dialyzer
dialyzer (di′a-li-zer)

The apparatus for performing dialysis; a membrane used in dialysis.

diamagnetic
diamagnetic (di′a-mag-net′ik)

Having the property of diamagnetism.

diamagnetism
diamagnetism (di-a-mag′ne-tizm)

The property displayed by substances that have a very small negative magnetic susceptibility, given by molecules in which all electrons are paired; an unpaired electron yields a magnetic movement, hence the molecule containing such exhibits paramagnetism.

di-amelia
di-amelia (di-a-me′le-a)

Absence of two limbs.

diameter
diameter (di-am′e-ter)

1. A straight line connecting two opposite points on the surface of a more or less spherical or cylindrical body, or at the boundary of an opening or foramen, passing through the center of such body or opening. 2. The distance measured along such a line. [G. diametros, fr. dia, through, + metron, measure]
anteroposterior d. of the pelvic inlet SYN: median conjugate.
biparietal d. the d. of the fetal head between the two parietal eminences.
buccolingual d. the d. of the crown of a tooth measured from the buccal to the lingual surfaces.
conjugate d. of pelvic inlet SYN: median conjugate.
conjugate d. of pelvic outlet SYN: straight conjugate.
diagonal conjugate d. SYN: diagonal conjugate.
external conjugate d. SYN: external conjugate.
d. obliqua [TA] SYN: oblique d..
oblique d. [TA] a measurement across the pelvic inlet from the sacroiliac joint of one side to the opposite iliopectineal eminence. SYN: d. obliqua [TA] .
obstetric conjugate d. SYN: true conjugate.
occipitofrontal d. the d. of the fetal head from the external occipital protuberance to the most prominent point of the frontal bone in the midline.
occipitomental d. the d. of the fetal head from the external occipital protuberance to the midpoint of the chin.
posterior sagittal d. distance from the sacrococcygeal junction to the middle of an imaginary line running between the left and right ischial tuberosities.
suboccipitobregmatic d. the d. of the fetal head from the lowest posterior point of the occipital bone to the center of the anterior fontanelle.
total end-diastolic d. (TEDD) cross sectional d. of the left ventricle including the septum and posterior wall thicknesses in diastole.
total end-systolic d. (TESD) cross sectional d. of the left ventricle including the septum and posterior wall thicknesses in systole.
trachelobregmatic d. the d. of the fetal head from the middle of the anterior fontanelle to the neck.
d. transversa [TA] SYN: transverse d..
transverse d. [TA] the transverse d. of the pelvic inlet, measured between the terminal lines. SYN: d. transversa [TA] .
zygomatic d. the extreme breadth of the skull at the zygomatic arches.

diamide
diamide (di′am-id, -id)

A compound containing two amide groups.

diamidines
diamidines (di-am′i-denz)

A group of compounds containing two amidine groups; e.g., stilbamidine, propamidine.

diamine
diamine (di′a-men, -min)

An organic compound containing two amine groups per molecule; e.g., ethylenediamine, NH₂CH₂CH₂NH₂.
d. oxidase SYN: amine oxidase (copper-containing), amine oxidase (flavin-containing).

diamniotic
diamniotic (di-am-ne-ot′ik)

Exhibiting two amniotic sacs.

Diamond
Diamond

Louis K., U.S. physician, 1902–1995. See D.-Blackfan anemia, D.-Blackfan syndrome, Gardner-D. syndrome, Shwachman-D. syndrome.

diamthazole dihydrochloride
diamthazole dihydrochloride (di-am′tha-zol)

An antifungal agent for topical use. SYN: dimazole dihydrochloride.

diandry
diandry, diandria (di′an-dre, di-an′dre-a)

The phenomenon in which a single ovum is fertilized by a diploid sperm and hence produces a triploid fetus. Cf.:digyny. [di- + G. andros, male]

dianoetic
dianoetic (di′a-no-et′ik)

Of or pertaining to reason or other intellectual functions. [G. dia, through, + noeo, to think]

diapause
diapause (di′a-pawz)

A period of biological quiescence or dormancy with decreased metabolism; an interval in which development is arrested or greatly slowed. [dia- + G. pausis, pause]
embryonic d. a d. in the course of embryogenesis; postulated to occur in instances of double parturition and possibly of delayed implantation.

diapedesis
diapedesis (di′a-pe-de′sis)

The passage of blood, or any of its formed elements, through the intact walls of blood vessels. SYN: migration (2) . [G. dia, through, + pedesis, a leaping]

diaphanography
diaphanography (di-a-fa-nog′ra-fe)

Examination of a body part by transillumination, especially for the detection of breast cancer. [G. diaphanes, transparent, + grapho, to write]

diaphanoscope
diaphanoscope (di-af′a-no-skop)

An instrument for illuminating the interior of a cavity to determine the translucency of its walls. SYN: polyscope. [G. diaphanes, transparent, + skopeo, to examine]

diaphanoscopy
diaphanoscopy (di-af-a-nos′ko-pe)

Examination of a cavity with a diaphanoscope.

diaphemetric
diaphemetric (di′a-fe-met′rik)

Relating to the determination of the degree of tactile sensibility. [G. dia, through, + haphe, touch, + metron, measure]

diaphen hydrochloride
diaphen hydrochloride (di′a-fen)

An antihistaminic agent with anticholinergic properties.

diaphorase
diaphorase (di-af′or-as)

Originally, a series of flavoproteins with reductase activity in mitochondria; now dihydrolipoamide dehydrogenase.

diaphoresis
diaphoresis (di′a-fo-re′sis)

SYN: perspiration (1) . [G. d., fr. dia, through, + phoreo, to carry]

diaphoretic
diaphoretic (di-a-fo-ret′ik)

1. Relating to, or causing, perspiration. 2. An agent that increases perspiration.

diaphragm
diaphragm (di′a-fram)

1. The musculomembranous partition between the abdominal and thoracic cavities. SYN: diaphragma (2) [TA] , interseptum, midriff, phren (1) . 2. A thin disk pierced with an opening, used in a microscope, camera, or other optical instrument in order to shut out the marginal rays of light, thus giving a more direct illumination. 3. A flexible ring covered with a dome-shaped sheet of elastic material used in the vagina to prevent pregnancy. 4. In radiography, a grid (2) or a lead sheet with an aperture. See collimator. [G. diaphragma]
aperture d. a metal device that limits the area of the beam emerging from an x-ray tube.
Bucky d. in radiography, a d. with a moving grid that avoids grid shadows. SYN: Potter-Bucky d..
d. of mouth SYN: mylohyoid (muscle).
pelvic d. the paired levator ani and coccygeus muscles together with the fascia above and below them. SYN: d. of pelvis, diaphragma pelvis.
d. of pelvis SYN: pelvic d..
Potter-Bucky d. SYN: Bucky d..
d. sellae SYN: diaphragma sellae.
sellar d. diaphragma sellae.
d. of sella turcica SYN: diaphragma sellae.
urogenital d. an obsolete concept of a trilaminar, triangular sheet of muscle and fascia spanning the ischiopubic rami; composed of the sphincter urethrae and the deep transverse perineal muscles (which were said to be flat muscles forming a continuous sheet), plus the perineal membrane below and a superior fascia of the d. above. Evidence of the latter is lacking. The muscle-containing space between the fascial structures was formerly referred to as the deep perineal space. The terms urogenital d. and deep perineal space are not recognized by Terminologia Anatomica due to more accurate understanding of the morphology, especially of the sphincter urethrae. SYN: diaphragma urogenitale.

diaphragma
diaphragma, pl .diaphragmata (di-a-frag′ma, -frag′ma-ta) [TA]

1. A thin partition separating adjacent regions. 2. SYN: diaphragm (1) . [G. d., a partition wall, midriff]
d. oris SYN: mylohyoid (muscle).
d. pelvis SYN: pelvic diaphragm.
d. sellae [TA] a fold of dura mater extending transversely across the sella turcica and roofing over the hypophyseal fossa; it is perforated in its center for the passage of the infundibulum. SYN: sellar diaphragm&star, diaphragm of sella turcica, diaphragm sellae, tentorium of hypophysis.
d. urogenitale SYN: urogenital diaphragm.

diaphragmalgia
diaphragmalgia (di′a-frag-mal′je-a)

Rarely used term for a pain in the diaphragm. SYN: diaphragmodynia. [diaphragm + G. algos, pain]

diaphragmatic
diaphragmatic (di′a-frag-mat′ik)

Relating to a diaphragm. SYN: phrenic (1) .

diaphragmatocele
diaphragmatocele (di′a-frag-mat′o-sel)

Rarely used term for diaphragmatic hernia. [diaphragm + G. kele, hernia]

diaphragmodynia
diaphragmodynia (di′a-frag-mo-din′e-a)

SYN: diaphragmalgia. [diaphragm + G. odyne, pain]

diaphyseal
diaphyseal (di-a-fiz′e-al)

SYN: diaphysial.

diaphysectomy
diaphysectomy (di′a-fi-sek′to-me)

Partial or complete removal of the shaft of a long bone. [diaphysis + G. ektome, excision]

diaphysial
diaphysial (di-a-fiz′e-al)

Relating to a diaphysis. SYN: diaphyseal.

diaphysis
diaphysis, pl .diaphyses (di-af′i-sis, -sez) [TA]

An elongated rodlike structure, as the part of a long bone between the epiphysial extremities. The shaft of a long bone, as distinguished from the epiphyses, or extremities, and apophyses, or outgrowths. SYN: shaft [TA] . [G. a growing between]

diaphysitis
diaphysitis (di-af-i-si′tis)

Inflammation of the shaft of a long bone.

diapiresis
diapiresis (di′a-pi-re′sis)

Passage of colloidal or other small particles of suspended matter through the unruptured walls of the blood vessels. SEE ALSO: diapedesis. [G. diapeiro, to drive through, fr. peiro, to pierce]

diaplacental
diaplacental (di′a-pla-sen′tal)

Passing through or “across” the placenta.

diaplexus
diaplexus (di-a-plek′sus)

Rarely used term for choroid plexus of third ventricle. [G. dia, through, + L. plexus, a plaiting]

diapnoic
diapnoic, diapnotic (di-ap-no′ik, -not′ik)

1. Relating to, or causing perspiration, especially insensible perspiration. 2. A mild sudorific.

diapophysis
diapophysis

SYN: superior articular process.

Diaptomus
Diaptomus (di-ap′to-mus)

A genus of copepod crustacea, the principal intermediate host for Diphyllobothrium latum in North America.

diarrhea
diarrhea (di-a-re′a)

An abnormally frequent discharge of semisolid or fluid fecal matter from the bowel. [G. diarrhoia, fr. dia, through, + rhoia, a flow, a flux]
cachectic d. d. occurring in patients with severe wasting. Usually due to underlying gastrointestinal disease.
choleraic d. SYN: summer d..
chronic bacillary d. prolonged d. occurring in association with bacterial infection, usually occurring in patients with gastrointestinal stasis, allowing bacterial proliferation in the intestine with secondary malabsorption. Occurs in blind-loop syndrome after intestinal surgery, following vagotomy, and occasionally in scleroderma or diabetes.
Cochin China d. obsolete term for tropical sprue.
colliquative d. d. associated with excessive discharge of fluid.
dientamoeba d. d. thought to be due to infection with the flagellate, Dientamoeba fragilis.
dysenteric d. d. in bacillary or amebic dysentery.
fatty d. d. seen in malabsorption syndromes including chronic pancreatic disease, characterized by foul smelling stools with increased fat content that usually float in water. SYN: pimelorrhea.
flagellate d. d. due to infection with flagellate Giardia lamblia.
gastrogenous d. a d. that may occur in achylia gastrica, or that is caused by excess secretion of gastric and other intestinal juices.
lienteric d. d. in which undigested food appears in the stools.
morning d. a form in which there are several loose stools in the early morning and during the forenoon, the bowels being quiet during the remainder of the day and night.
mucous d. d. with the presence of considerable mucus in the stools.
nocturnal d. d. that occurs chiefly at night, usually in association with diabetic autonomic neuropathy.
pancreatic d. SYN: d. pancreatica.
d. pancreatica (pan-kre-a′ti-ka) d. characterized by severe, watery, secretory d. and hyperkalemia; most patients have hypercalcemia, many have hyperglycemia; results from excessive secretion of VIP (vasoactive intestinal peptide) by an islet cell tumor of the pancreas. Sometimes called WDHA syndrome. See Verner-Morrison syndrome, WDHA syndrome. SYN: pancreatic cholera, pancreatic d..
pancreatogenous d. d. in which the stools are bulky, pale, foul, greasy, and oily, as a result of malabsorption of fat due to deficient secretion of pancreatic enzymes in chronic pancreatitis.
serous d. d. characterized by watery stools.
summer d. d. of infants in hot weather, usually an acute gastroenteritis due to the presence of Shigella or Salmonella. SYN: choleraic d..
toddler's d. recurrent loose stools usually seen in otherwise healthy, normally growing children between the ages of 1 and 3 years, and occurring in daytime; often due to excessive fluid intake.
traveler's d. d. of sudden onset, often accompanied by abdominal cramps, vomiting, and fever, occurring sporadically in travelers usually during the first week of a trip; most commonly caused by unfamiliar strains of enterotoxigenic Escherichia coli.
tropical d. SYN: tropical sprue.

diarrheal
diarrheal, diarrheic (di-a-re′al, -re′ik)

Relating to diarrhea. SYN: diarrhetic.

diarrhetic
diarrhetic

SYN: diarrheal.

diarthric
diarthric (di-ar′thrik)

Relating to two joints. SYN: biarticular, diarticular. [G. di-, two, + arthron, joint]

diarthrosis
diarthrosis, pl .diarthroses (di-ar-thro′sis, -sez)

synovial joint. [G. articulation]

diarticular
diarticular (di-ar-tik′u-lar)

SYN: diarthric.

diaschisis
diaschisis (di-as′ki-sis)

A sudden inhibition of function produced by an acute focal disturbance in a portion of the brain at a distance from the original site of injury, but anatomically connected with it through fiber tracts. [G. a splitting]

diascope
diascope (di′a-skop)

A flat glass plate through which one can examine superficial skin lesions by means of pressure. [G. dia, through, + skopeo, to view]

diascopy
diascopy (di-as′ko-pe)

Examination of superficial skin lesions with a diascope. [G. dia, through, + skopeo, to see]

diastalsis
diastalsis (di-a-stal′sis)

The type of peristalsis in which a region of inhibition precedes the wave of contraction, as seen in the intestinal tract. [G. an arrangement]

diastaltic
diastaltic (di-a-stal′tik)

Pertaining to diastalsis.

diastase
diastase (di′as-tas)

A mixture, obtained from malt and containing amylolytic enzymes (principally α- and β-amylases), that converts starch into dextrin and maltose; used to make soluble starches, to aid in digestion of starches in certain types of dyspepsia, and to digest glycogen in histologic sections. [Fr., fr. G. diastasis, separation, fr. dia, apart + histemi, to make to stand]

diastasis
diastasis (di-as′ta-sis)

1. Any simple separation of normally joined parts. SYN: divarication. 2. The mid-portion of diastole when the blood enters the ventricle slowly or ceases to enter prior to atrial systole. D. duration is in inverse proportion to heart rate and is absent at very high heart rates. [G. a separation]
d. recti separation of rectus abdominis muscles away from the midline, sometimes seen during or following pregnancy.

diastasuria
diastasuria (di-as-tas-u′re-a)

SYN: amylasuria.

diastatic
diastatic (di-a-stat′ik)

Relating to a diastasis.

diastema
diastema, pl .diastemata (di′a-ste′ma, -ste′ma-ta) [TA]

1. Fissure or abnormal opening in any part, especially if congenital. 2. [NA] Space between two adjacent teeth in the same dental arch. 3. Cleft or space between the maxillary lateral incisor and canine teeth, into which the lower canine is received when the jaws are closed; abnormal in humans but normal in dogs and many other animals. [G. d., an interval]

diastematocrania
diastematocrania (di-a-ste′ma-to-kra′ne-a)

Congenital sagittal fissure of the skull. [G. diastema, an interval, + kranion, skull]

diastematomyelia
diastematomyelia (di-a-ste′ma-to-mi-e′le-a)

Complete or incomplete sagittal division of the spinal cord by an osseous or fibrocartilaginous septum. [G. diastema, interval, + myelon, marrow]

diaster
diaster (di′as-ter)

SYN: amphiaster. [G. di-, two, + aster, star]

diastereoisomers
diastereoisomers (di′a-star-e-o-i′so-merz)

Optically active isomers that are not enantiomorphs (mirror images); e.g., d-glucose and d-galactose.

diastole
diastole (di-as′to-le)

Normal postsystolic dilation of the heart cavities, during which they fill with blood; d. of the atria precedes that of the ventricles; d. of either chamber alternates rhythmically with systole or contraction of that chamber. [G. d., dilation]
atrial d. period of relaxation and repolarization of the atrial muscle.
electrical d. period from end of T wave to beginning of next Q wave.
gastric d. a phase of relaxation of stomach peristalsis seen fluoroscopically or with the gastroscope.
late d. SYN: presystole.
ventricular d. period of relaxation and repolarization of the ventricular muscle.

diastolic
diastolic (di-a-stol′ik)

Relating to diastole.

diastology
diastology (di-as-tol′o-je)

The study or science of cardiac diastole and its components.

diastrophism
diastrophism (di-as′trof-izm)

Distortion that occurs in objects as a result of bending. [G. diastrophe, fr. diastrephein, distortion]

diataxia
diataxia (di′a-tak′se-a)

Ataxia affecting both sides of the body.
cerebral d. the ataxic type of cerebral birth palsy.

diatela
diatela (di-a-te′la)

Rarely used term for tela choroidea of third ventricle. [G. dia, through, between, + L. tela, web]

diathermal
diathermal (di-a-ther′mal)

SYN: diathermic. [G. dia, through, + therme, heat]

diathermancy
diathermancy (di-a-ther′man-se)

The condition of being diathermic.

diathermanous
diathermanous (di-a-ther′man-us)

Permeable by heat rays. SYN: transcalent. [G. dia-thermaino, to heat through, fr. thermos, hot]

diathermic
diathermic (di-a-ther′mik)

Relating to, characterized by, or affected by diathermy. SYN: diathermal.

diathermocoagulation
diathermocoagulation (di-a-ther′mo-ko-ag-u-la′shun)

SYN: surgical diathermy.

diathermy
diathermy (di′a-ther-me)

Local elevation of temperature within the tissues, produced by high frequency current, ultrasonic waves, or microwave radiation. SYN: transthermia. [G. dia, through, + therme, heat]
medical d. d. of mild degree causing no destruction of tissue. SYN: thermopenetration.
short wave d. therapeutic elevation of temperature in the tissues by means of an oscillating electric current of extremely high frequency (10–100 million Hz) and short wavelength of 3–30 meters.
surgical d. electrocoagulation with a high frequency electrocautery, resulting in local tissue destruction; usually used to seal blood vessels and arrest bleeding. SYN: diathermocoagulation.
ultrashortwave d. shortwave d. in which the wavelength is under 10 meters.

diathesis
diathesis (di-ath′e-sis)

The constitutional or inborn state disposing to a disease, group of diseases, or metabolic or structural anomaly. [G. arrangement, condition]
contractural d. an older term denoting a tendency to have contractures in hysteria.
cystic d. a condition in which multiple cysts form in the liver, kidneys, and other organs.
gouty d. a state of susceptibility to attacks of gout or development of tophi, usually associated with hyperuricemia or hyperexcretion of urate in urine.
spasmophilic d. a condition in which there is an abnormal excitability of the motor nerves, shown by a tendency to tetany, laryngeal spasm, or general convulsions.

diathetic
diathetic (di-a-thet′ik)

Relating to a diathesis.

diatom
diatom (di′a-tom)

An individual of microscopic unicellular algae, the shells of which compose a sedimentary infusorial earth. [G. diatomos, cut in two]

diatomaceous
diatomaceous (di′a-to-ma′shus)

Pertaining to diatoms or their fossil remains.

diatomic
diatomic (di-a-tom′ik)

1. Denoting a compound with a molecule made up of two atoms. 2. Denoting any ion or atomic grouping composed of two atoms only.

diatoric
diatoric (di′a-tor′ik)

1. The vertical cylindric aperture formed in the base of artificial porcelain teeth and extending into the body of the tooth, serving as a mechanical means of attaching the tooth to the denture base. 2. Denoting teeth that contain a d.. [G. diatoros, pierced]

diatrizoate
diatrizoate

Salt of 3,5-diacetamido-2,4,6-triiodobenzoic acid. See sodium d..

diazepam
diazepam (di-az′e-pam)

A skeletal muscle relaxant, sedative, and antianxiety agent; also used as an anticonvulsant, particularly in the treatment of status epilepticus by the parenteral route.

diazines
diazines (di′a-zenz)

A group of synthetic tuberculostatic drugs, such as pyrazine carboxamide and pyridazine-3-carboxamide.

diazinon
diazinon (di-az′in-on)

A sulfur-containing organophosphate compound used as an insecticide and cholinesterase inhibitor.

diazo- diazo-

Prefix denoting a compound containing the R&cbond;N&dbond;N&cbond;X or R&dbond;N₂ grouping, where X is not carbon (except for CN). An example is diazomethane, CH₂N₂. Cf.:azo-. [G. di-, two, + Fr. azote, nitrogen]

diazotize
diazotize (di-az′o-tiz)

To introduce the diazo group into a chemical compound, usually through the treatment of an amine with nitrous acid.

diazoxide
diazoxide (di-a-zok′sid)

An antihypertensive agent.

dibasic
dibasic (di-ba′sik)

Having two replaceable hydrogen atoms, denoting an acid with two ionizable hydrogen atoms.

dibenamine
dibenamine (di-ben′a-men)

A nonspecific and irreversible antagonist at alpha-adrenergic receptors. Prevents vasoconstriction produced by epinephrine and norepinephrine and similar agents causing vasoconstriction by an action on alpha adrenergic receptors.

dibenzepin hydrochloride
dibenzepin hydrochloride (di-benz′e-pin)

An antidepressant.

dibenzheptropine citrate
dibenzheptropine citrate (di-benz-hep′tro-pen)

SYN: deptropine citrate.

dibenzopyridine
dibenzopyridine (di-ben′zo-pir′i-den)

SYN: acridine.

dibenzothiazine
dibenzothiazine (di-ben′zo-thi′a-zen)

SYN: phenothiazine.

dibenzthione
dibenzthione (di-benz-thi′on)

An antifungal antiseptic. SYN: sulbentine.

Dibothriocephalus
Dibothriocephalus (di-both′re-o-sef′a-lus)

Former name for Diphyllobothrium. [G. di-, two, + bothrion, dim. of bothros, a pit, + kephale, head]
D. latus SYN: Diphyllobothrium latum.

dibromopropamidine isethionate
dibromopropamidine isethionate (di-bro′mo-pro-pam′i-den)

An antiseptic.

dibromsalan
dibromsalan (di-brom′sa-lan)

A disinfectant.

dibucaine
dibucaine (di′boo-kan)

A potent local anesthetic with a long duration of action used by injection or topically on skin or mucous membranes.

dibucaine hydrochloride
dibucaine hydrochloride (di-bu′kan)

A potent local anesthetic (surface and spinal anesthesia).

dibucaine number
dibucaine number (DN)

A test for differentiation of one of several forms of atypical pseudocholinesterases that are unable to inactivate succinylcholine at normal rates; based upon percent inhibition of the enzymes by dibucaine, normal enzyme has a DN of 75 and above, heterozygous atypical enzyme has a DN of 40-70, and homozygous atypical enzyme has a DN of less than 20. SEE ALSO: fluoride number.

dibutoline sulfate
dibutoline sulfate (di-bu′to-len)

An anticholinergic agent used as a mydriatic, a cycloplegic, and a gastrointestinal antispasmodic.

dibutyl phthalate
dibutyl phthalate (di-bu′til thal′at)

An insect repellent.

DIC
DIC

Abbreviation for disseminated intravascular coagulation.

dicacodyl
dicacodyl (di-kak′o-dil)

SYN: cacodyl.

dicelous
dicelous (di-se′lus)

Having two cavities or excavations on opposite surfaces. [G. di-, two, + koilos, hollow]

dicentric
dicentric (di-sen′trik)

Referring to a structural chromosome having two centromeres, an abnormal state.

dicephalous
dicephalous (di-sef′a-lus)

Having two heads.

dicephalus
dicephalus (di-sef′a-lus)

Symmetrical conjoined twins with two separate heads. See conjoined twins, under twin. SYN: bicephalus, diplocephalus. [G. di-, two, + kephale, head]
d. diauchenos a d. with separate necks. SYN: derodidymus.
d. dipus dibrachius a d. in which there are only two arms and two legs for a body with two axes.
d. dipus tetrabrachius a d. with two legs and four separate arms.
d. dipus tribrachius a d. with two legs and three arms.
d. dipygus SYN: anakatadidymus. See conjoined twins, under twin.
d. monauchenos a d. in which union involves the cervical region so that the two heads are on a single neck.

dicheilia
dicheilia, dichilia (di-ki′le-a)

A lip appearing to be double because of the presence of an abnormal fold of mucosa. [G. di-, two, + cheilos, lip]

dicheiria
dicheiria, dichiria (di-ki′re-a)

Complete or incomplete duplication of the hand. SEE ALSO: polydactyly. SYN: diplocheiria, diplochiria. [G. di-, two, + cheir, hand]

Dichelobacter nodosus
Dichelobacter nodosus

SYN: Bacteroides nodosus.

dichloramine-T
dichloramine-T (di-klor′a-men)

Used as an antiseptic in surgical dressings.

dichloride
dichloride (di-klor′id)

A compound with a molecule containing two atoms of chlorine to one of another element.

dichlorisone
dichlorisone (di-klor′i-son)

A topical antipruritic agent.

dichlorobenzene
dichlorobenzene (di-klor′o-ben′zen)

An insecticide used chiefly as a moth repellent.

dichlorodifluoromethane
dichlorodifluoromethane (di-klor′o-di-floo-ro-meth′an)

An easily liquefiable gas used as a refrigerant and aerosol propellant.

dichlorodiphenyltrichloroethane
dichlorodiphenyltrichloroethane (DDT) (di-chlor′o-di-fen′il-tri-klor-o-eth′an)

An insecticide that came into prominence during and after World War II. For a time it proved very effective, but insect populations rapidly developed tolerance for it, hence much of its original effectiveness has been lost; general usage is now widely discouraged because of the toxicity that results from the environmental persistence of this agent. SYN: chlorophenothane, dicophane.

di(2-chloroethyl)sulfide
di(2-chloroethyl)sulfide

SYN: mustard gas.

dichloroformoxime
dichloroformoxime

SYN: phosgene oxime.

dichlorohydrin
dichlorohydrin (di-klor-o-hi′drin)

A colorless, odorless fluid prepared by heating anhydrous glycerin with sulfur monochloride; a solvent of resins. SYN: dichloroisopropyl alcohol.

2,6-dichloroindophenol
2,6-dichloroindophenol (di-klor′o-in-do-fe′nol)

A reagent for the chemical assay of ascorbic acid that depends upon the reducing properties of the latter. It is red in acid solution; in the presence of the vitamin C it undergoes reduction and becomes colorless, the vitamin being oxidized to dehydroascorbic acid. Often misnamed dichlorophenol-indophenol.

dichloroisopropyl alcohol
dichloroisopropyl alcohol (di-klor′o-is-o-pro′pil)

SYN: dichlorohydrin.

dichlorophen
dichlorophen (di-klor′o-fen)

Used topically as a fungicide and bactericide, and internally in the treatment of infections by tapeworms of humans and domestic animals.

dichlorophenarsine hydrochloride
dichlorophenarsine hydrochloride (di-klor′o-fen-ar′sen)

(3-Amino-4-Hydroxyphenyl)dichloroarisine hydrochloride, formerly used as an arsenical antisyphilitic.

2,6-dichlorophenol-indophenol
2,6-dichlorophenol-indophenol (di′klor-o-fe′nol-in-do-fe′nol)

Misnomer for 2,6-dichloroindophenol.

(2,4-dichlorophenoxy) acetic acid
(2,4-dichlorophenoxy) acetic acid (2,4-D)

An herbicide, more toxic to broad-leaved dicotyledonous plants (weeds) than to monocotyledonous ones (grains and grass), used with (2,4,5-trichlorophenoxy)acetic acid as a constituent of Agent Orange.

dichlorovos
dichlorovos (di-klor′o-vos)

SYN: dichlorvos.

dichlorphenamide
dichlorphenamide (di-klor-fen′a-mid)

A carbonic anhydrase inhibitor with actions similar to those of acetazolamide.

dichlorvos
dichlorvos (di-klor′vos)

An anthelmintic in veterinary and human medicine. SYN: dichlorovos.

dichorial
dichorial, dichorionic (di-ko′re-al, di-ko-re-on′ik)

Showing evidence of two chorions. [G. di-, two, + chorion]

dichotic
dichotic (di-kot′ik)

1. SYN: dichotomous. 2. Simultaneous presentation of a different sound to each ear.

dichotomous
dichotomous (di-kot′o-mus)

Denoting or characterized by dichotomy. SYN: dichotic (1) .

dichotomy
dichotomy (di-kot′o-me)

Division into two parts. [G. dichotomia, a cutting in two, fr. dicha, in two, + tome, a cutting]

dichroic
dichroic (di-kro′ik)

Relating to dichroism.

dichroism
dichroism (di′kro-izm)

The property of seeming to be differently colored when viewed from emitted light and from transmitted light. [G. di-, two, + chroa, color]
circular d. (CD) the change from circular polarization to elliptical polarization of monochromatic, circularly polarized light in the immediate vicinity of the absorption band of the substance through which the light passes. SEE ALSO: Cotton effect.

dichromat
dichromat (di′kro-mat)

An individual with dichromatism.

dichromate
dichromate (di-kro′mat)

A compound containing the radical Cr₂O₇^&dbond;.

dichromatic
dichromatic (di-kro-mat′ik)

1. Having or exhibiting two colors. 2. Relating to dichromatism (2).

dichromatism
dichromatism (di-kro′ma-tizm)

1. The state of being dichromatic (1). 2. The abnormality of color vision in which only two of the three retinal cone pigments are present, as in protanopia, deuteranopia, and tritanopia. SYN: dichromatopsia. [G. di-, two, + chroma, color]

dichromatopsia
dichromatopsia (di-kro-ma-top′se-a)

SYN: dichromatism (2) . [G. di-, two, + chroma, color, + opsis, vision]

dichromic
dichromic (di-kro′mik)

Having, or relating to, two colors.

dichromophil
dichromophil, dichromophile (di-kro′mo-fil, di-kro′mo-fil)

Taking a double stain; denoting a tissue or cell taking both acid and basic dyes in different parts. [G. di-, two, + chroma, color, + philos, fond]

Dick
Dick

George Frederick, U.S. internist, 1881–1967. See D. method, D. test, D. test toxin.

Dick
Dick

Gladys R.H., U.S. internist, 1881–1963. See D. method, D. test, D. test toxin.

Dickens
Dickens

Frank, British biochemist, *1899. See D. shunt, Warburg-Lipmann-D.-Horecker shunt.

diclofenac
diclofenac (di-clo′fén-ák)

One of several nonsteroidal anti-inflammatory drugs used in the treatment of rheumatic disorders such as rheumatoid arthritis; also used in osteoarthritis and other conditions. Acts by preventing prostaglandin synthesis.

dicloxacillin sodium
dicloxacillin sodium (di-klok-sa-sil′in)

A semisynthetic penicillin resistant to penicillinase.

DICOM
DICOM

Abbreviation for Digital Imaging and Communications in Medicine, a joint standard of the American College of Radiology and National Equipment Manufacturers Association; specifies entities (or objects) and functions (or services) to allow communication between various image sources and other computer devices, such as archives or workstations.

dicophane
dicophane (di′ko-fan)

SYN: dichlorodiphenyltrichloroethane.

dicoria
dicoria (di-ko′re-a)

SYN: diplocoria. [G. di-, two, + kore, pupil]

dicotyledon
dicotyledon

Plant (shrub, herb, or tree) whose seeds consist of two cotyledons, i.e., the primary or rudimentary leaf of the embryo of seed plants.

dicrocoeliosis
dicrocoeliosis (di′kro-se-li-o′sis)

Infection of animals and, rarely, humans with trematodes of the genus Dicrocoelium.

Dicrocoelium
Dicrocoelium (dik-ro-se′le-um)

A genus of digenetic trematodes inhabiting the bile ducts and gallbladder of herbivores. The species D. dentriticum (lancet fluke) is rarely found in humans, but is an important parasite of sheep in some localities. [G. dikroos, forked, + koilia, belly]

dicrotic
dicrotic (di-krot′ik)

Relating to dicrotism. [G. dikrotos, double-beating]

dicrotism
dicrotism (di′kro-tizm)

That form of the pulse in which a double beat can be appreciated at any arterial pulse for each beat of the heart; due to accentuation of the dicrotic wave. [G. di-, two, + krotos, a beat]

dicta-
dicta- (dik′ta)

Prefix used to signify two hundred. [G.]

dictyoma
dictyoma (dik-te-o′ma)

A benign tumor of the ciliary epithelium with a netlike structure resembling embryonic retina. [G. dikyton, net (retina), + -oma, tumor]

dictyosome
dictyosome (dik′te-o-som)

SYN: Golgi apparatus. [G. diktyon, net, + -some]

dictyotene
dictyotene (dik′te-o-ten)

The state of meiosis at which the oocyte is arrested during the several years between late fetal life and menarche. [G. diktyon, net, + tainia, band]

dicumarol
dicumarol (di-koo′ma-rol)

An anticoagulant that inhibits the formation of prothrombin in the liver. Acts as an antagonist of vitamin K; discovered as the causative agent in spoiled hay, which produced bleeding in cattle (sweet clover disease). SYN: bishydroxycoumarin.

dicyclomine hydrochloride
dicyclomine hydrochloride (di-si′klo-men)

An anticholinergic agent.

dicysteine
dicysteine (di-sis′ten)

SYN: cystine.

didactic
didactic (di-dak′tik)

Instructive; denoting medical teaching by lectures or textbooks, as distinguished from clinical demonstrations with patients or laboratory exercises. [G. didaktikos, fr. didasko, to teach]

didactylism
didactylism (di-dak′ti-lizm)

Congenital condition of having only two fingers on a hand or two toes on a foot. [G. di-, two, + daktylos, finger or toe]

didelphic
didelphic (di-del′fik)

Having or relating to a double uterus. [G. di-, two, + delphys, womb]

Didelphis
Didelphis (di-del′fis)

A genus of marsupials, commonly called opossums, that serve as reservoir hosts of Trypanosoma cruzi. D. marsupialis is the common North American variety; D. paraguayensis is a South American form. [G. di-, two, + delphys, womb]

dideoxyadenosine
dideoxyadenosine (DDA) (di′de-oks′e-a-den′o-sen)

An antiviral agent used in the treatment of AIDS, similar to DDC.

dideoxycytidine
dideoxycytidine (di′-de-ok′-se-si′-ti-den)

Pyrimidine nucleoside analog with antiviral activity; used in the treatment of AIDS.

dideoxyinosine
dideoxyinosine (DDI) (di′-de-oks-e-i′-no-sen)

Antiviral agent; has been used in treatment of AIDS.

DIDMOD
DIDMOD

An acronym for Wolfram syndrome, which comprises diabetes insipidus, diabetes mellitus, optic atrophy, and deafness.

didym- didym-, didymo-

The didymus, testis. [G. didymos, twin]

didymus
didymus (did′e-mus)

SYN: testis. [G. didymos, a twin, pl. didymoi, testes]

-didymus -didymus

A conjoined twin, with the first element of the complete word designating fused parts. SEE ALSO: -dymus, -pagus. [G. didymos, twin]

die
die (di)

In dentistry, the positive reproduction of the form of a prepared tooth in any suitable hard substance, usually in metal or specially prepared artificial stone. SEE ALSO: counterdie.

dieb. alt.
dieb. alt.

Abbreviation for L. diebus alternis, every other day.

diecious
diecious (di-e′shus)

Denoting animals or plants that are sexually distinct, the individuals being of one or the other sex. [G. di-, two, + oikia, house]

Dieffenbach
Dieffenbach

Johann F., German surgeon, 1792–1847.

Diego blood group
Diego blood group, Di blood group

See Blood Groups appendix.

diel
diel (di′el)

Term frequently used synonymously with diurnal (2) or circadian. [irreg., fr. L. dies, day]

dieldrin
dieldrin (di-el′drin)

A chlorinated hydrocarbon used as an insecticide; may cause toxic effects in persons and animals exposed to its action through skin contact, inhalation, or food contamination.

dielectrography
dielectrography (di-e-lek-trog′ra-fe)

SYN: impedance plethysmography.

dielectrolysis
dielectrolysis (di′e-lek-trol′i-sis)

SYN: electrophoresis.

Diels
Diels

Otto, German chemist and Nobel laureate, 1876–1954. See D. hydrocarbon.

diencephalohypophysial
diencephalohypophysial (di-en-sef′a-lo-hi-po-fiz′e-al)

Relating to the diencephalon and hypophysis.

diencephalon
diencephalon, pl .diencephala (di-en-sef′a-lon, -sef′a-la) [TA]

The caudal part of the prosencephalon composed of the epithalamus, thalamus, and hypothalamus. [G. dia, through, + enkephalos, brain]

diener
diener (de′ner)

A laboratory worker who assists in cleaning; most commonly applied to laboratory workers who assist in the performance of autopsies and maintenance of morgues. [Ger. D., servant]

dienestrol
dienestrol (di-en-es′trol)

An estrogenic agent. SYN: estrodienol.

Dientamoeba fragilis
Dientamoeba fragilis (di-ent-a-me′ba fraj′i-lis)

A species of small amebalike flagellates, formerly considered a true ameba, now recognized as an ameboflagellate related to Trichomonas, parasitic in the large intestine of humans and certain monkeys; may be nonpathogenic, but believed to be capable of sometimes causing low-grade inflammation with mucous diarrhea and gastrointestinal disturbance in humans.

dieresis
dieresis (di-er′e-sis)

SYN: solution of continuity. [G. diairesis, a division]

dieretic
dieretic (di-er-et′ik)

1. Relating to dieresis. 2. Dividing; ulcerating; corroding.

diesterase
diesterase (di-es′ter-as)

See phosphodiesterases.

diestrous
diestrous (di-es′trus)

Pertaining to diestrus.

diestrus
diestrus (di-es′trus)

A period of sexual quiescence intervening between two periods of estrus. [G. dia, between, + oistros, desire]

diet
diet (di′et)

1. Food and drink in general. 2. A prescribed course of eating and drinking in which the amount and kind of food, as well as the times at which it is to be taken, are regulated for therapeutic purposes. 3. Reduction of caloric intake so as to lose weight. 4. To follow any prescribed or specific d.. [G. diaita, a way of life; a d.]
acid-ash d. SYN: alkaline-ash d..
alkaline-ash d. a d. consisting mainly of fruits, vegetables, and milk (with minimal amounts of meat, fish, eggs, cheese, and cereals), which, when catabolized, leave an alkaline residue to be excreted in the urine. SYN: acid-ash d., basic d..
balanced d. a d. containing the essential nutrients with a reasonable ration of all the major food groups.
basal d. 1. a d. having a caloric value equal to the basal heat production and sufficient quanties of essential nutrients to meet basic needs; 2. in experiments in nutrition, a d. complete and adequate except for a single constituent ( e.g., a vitamin, mineral, or amino acid), the nutritional value of which is to be determined, is omitted for a period and the effects observed; the subject is observed for a second period during which the ingredient being studied is added to the d..
basic d. SYN: alkaline-ash d..
bland d. a regular d. omitting foods that mechanically or chemically irritate the gastrointestinal tract.
BRAT d. a limited d. often used in regimens for acute gastroenteritides; acronym for bananas, rice, apples (juice or sauce), and toast.
challenge d. a d. in which one or more specific substances are included for the purpose of determining whether an abnormal reaction occurs.
clear liquid d. a d., often used postoperatively, consisting usually of water, tea, coffee, gelatin preparations, and clear soups or broth.
diabetic d. a dietary adjustment for patients with diabetes mellitus intended to decrease the need for insulin or oral diabetic agents and control weight by adjusting caloric and carbohydrate intake.
elimination d. a d. designed to detect what ingredient of the food causes allergic manifestations in the patient; food items to which the patient may be sensitive are withdrawn separately and successively from the d. until that which causes the symptoms is discovered.
full liquid d. a d. consisting only of liquids but including cream soups, ice cream, and milk.
Giordano-Giovannetti d. a d. designed for patients with renal failure; it provides small amounts of protein, primarily as essential amino acids, along with alpha-keto derivatives of amino acids; breakdown of protein in skeletal muscle is retarded and, because transaminase reactions are reversible, a small proportion of the ammonia released by urea breakdown is used for synthesis of nonessential amino acids. SYN: Giovannetti d..
Giovannetti d. SYN: Giordano-Giovannetti d..
gluten-free d. elimination of all wheat, rye, barley, and oat gluten from the d.; treatment for gluten-sensitive enteropathy (celiac disease). See celiac disease.
gout d. a d. containing a minimal quantity of purine bases (meats); liver, kidney, and sweetbread especially are excluded and replaced by dairy products, fruits, and cereals; alcoholic beverages also are excluded. SYN: purine-free d..
high-calorie d. a d. containing upward of 4,000 calories per day.
high-fat d. a d. containing large amounts of fat.
high-fiber d. a d. high in the nondigestible part of plants, which is fiber. Fiber is found in fruits, vegetables, whole grains, and legumes. Insoluble fiber increases stool bulk, decreases transit time of food in the bowel, and decreases constipation and the risk of colon cancer. Soluble fiber delays absorption of glucose, which helps to control blood sugar in diabetes mellitus, and delays absorption of lipids, which helps to control hyperlipidemia. Recommended in treatment of diverticular disease of the colon.
Kempner d. SYN: rice d..
ketogenic d. a high-fat, low-carbohydrate, and normal protein d. causing ketosis.
low-calorie d. a d. of 1,200 calories or less per day.
low-fat d. a d. containing a minimal proportion of fat.Diets containing low amounts of fat and cholesterol are designed to reduce the risk of cardiovascular disease, specifically atherosclerosis. The National Cholesterol Education Program recommends maintaining a total cholesterol level of no more than 200 mg/dL, with LDL cholesterol less than 130 mg/dL and HDL cholesterol at least 60 mg/dL. (According to the National Institutes of Health, LDL cholesterol in patients with atherosclerotic heart disease should not exceed 100 mg/dL.) About one-half of adult Americans exceed these total cholesterol and LDL cholesterol limits; for many, the reason is an inborn metabolic disorder of lipid metabolism not correctable by dietary restrictions alone. A low-fat d. should derive less than 10% of its calories from saturated fat (meats, dairy products) and should be low in cholesterol (<300 mg/d) and trans fatty acids (e.g., hydrogenated oils as in stick margarine and shortening) and rich in whole grains, fresh fruits and vegetables, and legumes. People who follow an extremely low-fat d. experience some reversal in atherosclerosis despite a concomitant decrease in HDL cholesterol. A low-fat d. may also help decrease body weight or prevent weight gain, because fats and oils yield more than twice as many calories per gram as carbohydrate and protein foods. See atherosclerosis; free radical.
low purine d. a d. low in precursors of purines (such as tissues rich in cells with abundant nuclei, as in liver, glandular meats, etc.) to minimize formation of uric acid. Useful in treatment of patients with gout or urate-containing renal calculi.
low residue d. a d. that leaves minimal unabsorbed components in the intestine, to minimize functional stress on the colon.
low salt d. a d. with restricted amounts of sodium chloride, useful in the treatment of some cases of hypertension, heart failure, and other syndromes characterized by fluid retention and/or edema formation.
macrobiotic d. a d. claimed to promote longevity, often by promoting an emphasis on natural foods and restrictions on noncereal foods, as well as liquids.
Meulengracht d. a feeding program for patients with peptic ulcer disease, containing a relatively full d. free of acidic or highly seasoned food.
Minot-Murphy d. the use of large amounts of raw liver in the treatment of pernicious anemia. First successes in the treatment of this disease occurred with this d. and led to development of liver extract for treatment.
Ornish prevention diets relaxed versions of the Ornish reversal d., which is designed to prevent coronary artery disease. These diets reduce dietary fat in proportion to blood cholesterol level.
Ornish reversal d. a d. designed by Dean Ornish, who has evidence that it will reverse coronary artery disease. It consists of 10% of calories from fat (mostly polyunsaturated or monounsaturated, with 5 mg cholesterol per day), 70–75% from carbohydrate, and 15–20% from protein.
purine-free d. SYN: gout d..
purine-restricted d. gout d..
rachitic d. a d. that will induce rickets in susceptible experimental animals.
reducing d. a d. in which caloric expenditure is greater than caloric intake.
rice d. a d. of rice, fruit, and sugar, plus vitamin and iron supplements, devised by Kempner to treat hypertension. In 2,000 calories, the d. contains 5 gm or less of fat, about 20 gm of protein, and not more than 150 mg of sodium. SYN: Kempner d..
Schmidt d. SYN: Schmidt-Strassburger d..
Schmidt-Strassburger d. an obsolete d. designed to facilitate examination of the stools in patients with diarrhea, consisting of milk, zwieback, oatmeal gruel, eggs, butter, small amounts of beef and potato. SYN: Schmidt d..
Sippy d. a d. formerly used in the initial stages of treatment of peptic ulcer, beginning with milk and cream every hour or two to keep gastric acid neutralized, gradually increasing to include cereal, eggs and crackers after three days, pureed vegetables later.
smooth d. a d. containing little roughage; used primarily in diseases of the colon.
soft d. a normal d. limited to soft foods for those who have difficulty chewing or swallowing; there are no restrictions on seasoning or method of food preparation.
subsistence d. a meager d. providing barely enough for sustenance.
Wilder d. obsolete d., low in potassium, for treating Addison disease.

dietary
dietary (di′e-tar-e)

Relating to the diet.

Dieterle stain
Dieterle stain

See under stain.

dietetic
dietetic (di′e-tet′ik)

1. Relating to the diet. 2. Descriptive of food that, naturally or through processing, has a low caloric content.

dietetics
dietetics (di-e-tet′iks)

The practical application of diet in the prophylaxis and treatment of disease.

diethadione
diethadione (di-eth-a-di′on)

An analeptic.

diethanolamine
diethanolamine (di-eth-a-nol′a-men)

Used as an emulsifier and as a dispersing agent in cosmetics and pharmaceuticals. SYN: diethylolamine.

diethazine
diethazine (di-eth′a-zen)

An anticholinergic agent.

diethyl
diethyl (di-eth′il)

A compound containing two ethyl radicals.

5,5-diethylbarbituric acid
5,5-diethylbarbituric acid (di-eth′il-bar-bi-tu′rik)

SYN: barbital.

diethylcarbamazine citrate
diethylcarbamazine citrate (di-eth′il-kar-bam′a-zen)

An effective microfilaricide, although relatively ineffective against the adult filariae.

diethylenediamine
diethylenediamine (di-eth′il-en-di′a-men)

SYN: piperazine.

1,4-diethylene dioxide
1,4-diethylene dioxide (di-eth′il-en)

SYN: dioxane.

diethylene glycol
diethylene glycol (di-eth′il-en)

An organic solvent chemically related to ethylene glycol. Upon metabolic conversion it becomes oxalic acid, which is toxic to the kidney. A sweet, viscous liquid that was used to make the infamous elixir of sulfanilamide that proved fatal to over 100 children in 1937, leading to the mandate to the FDA to monitor drug safety.

diethylenetriamine pentaacetic acid
diethylenetriamine pentaacetic acid (DTPA) (di-eth′il-en-tri′a-men pen-ta-a-se′tik as′id)

An important chelating agent used in therapy ( e.g., in therapy for lead poisoning), and in metal-containing diagnostic agents for magnetic resonance imaging and nuclear scanning.

diethyl ether
diethyl ether

A flammable, volatile organic solvent formerly widely used in surgical procedures; was used as an inhalation anesthetic; shortcomings include: irritating vapor, slow onset and prolonged recovery phase, explosion hazard. SYN: ethyl ether, ethyl oxide, sulfuric ether.

diethylolamine
diethylolamine (di-eth-i-lol′a-men)

SYN: diethanolamine.

diethylpropion hydrochloride
diethylpropion hydrochloride (di-eth-il-pro′pe-on)

A sympathomimetic drug resembling amphetamine in its actions and used as an appetite suppressant. Increases blood pressure, heart rate.

diethylstilbestrol
diethylstilbestrol (DES) (di-eth′il-stil-bes′trol)

A synthetic nonsteroidal estrogenic compound. Sometimes used as a postcoital antipregnancy agent to prevent implantation of the fertilized ovum. The first demonstrated transplacental carcinogen responsible for a delayed clear cell vaginal carcinoma in female offspring of mothers who took the drug during pregnancy when the drug was erroneously thought to prevent threatened abortion. SYN: stilbestrol.

diethyltoluamide
diethyltoluamide (di-eth′il-to-loo′a-mid)

An insect repellent.

diethyltryptamine
diethyltryptamine (DET) (di-eth-il-trip′ta-men)

A hallucinogenic agent similar to dimethyltryptamine.

dietitian
dietitian (di-e-tish′un)

An expert in dietetics.

Dietl
Dietl

Józef, Polish physician, 1804–1878. See D. crisis.

Dieuaide diagram
Dieuaide diagram

See under diagram.

Dieulafoy
Dieulafoy

Georges, French physician, 1839–1911. See D. erosion.

difarnesyl group
difarnesyl group (di-far′ne-sil)

A 30-carbon open chain hexaisoprenoid hydrocarbon radical; occurs as a side chain in vitamin K₂.

difenoxin
difenoxin (di-fen-ok′sin)

An antidiarrheal agent with actions similar to those of diphenoxylate. SYN: difenoxylic acid.

difenoxylic acid
difenoxylic acid (di-fen-ok′si-lik)

SYN: difenoxin.

difference
difference (dif′er-ens)

The magnitude or degree by which one quality or quantity differs from another of the same kind.
alveolar-arterial oxygen d. the d. or gradient between the partial pressure of oxygen in the alveolar spaces and the arterial blood: P_(A–a)0₂. Normally in young adults this value is less than 20 mm Hg. SEE ALSO: alveolar gas equation.
arteriovenous carbon dioxide d. the d. in carbon dioxide content (in mL per 100 mL blood) between arterial and venous blood.
arteriovenous oxygen d. the d. in the oxygen content (in mL per 100 mL blood) between arterial and venous blood.
AV d. abbreviation for arteriovenous d. of concentration of a substance.
cation-anion d. SYN: anion gap.
individual differences in clinical psychology, deviations of individuals from the group average or from each other.
light d. 1. the d. in light sensitivity of the two eyes; 2. SYN: brightness d. threshold.
masking level d. a technique of comparing threshold responses with masking noise presented in phase and out of phase with the test signal; release from masking is normal and indicates an intact brainstem auditory pathway.
standard error of d. a statistical index of the probability that a d. between two sample means is greater than zero.

differential
differential (dif-er-en′shal)

Relating to, or characterized by, a difference; distinguishing. [L. dif-fero, to carry apart, differ, fr. dis, apart]
threshold d. SYN: d. threshold.

differentiated
differentiated (dif-er-en′she-a-ted)

Having a different character or function from the surrounding structures or from the original type; said of tissues, cells, or portions of the cytoplasm.

differentiation
differentiation (dif′er-en-she-a′shun)

1. The acquisition or possession of one or more characteristics or functions different from that of the original type. SYN: specialization (2) . 2. SYN: differential diagnosis. 3. Partial removal of a stain from a histologic section to accentuate the staining differences of tissue components.
correlative d. d. due to the interaction of different parts of an organism.
echocardiographic d. the processing of a signal so that the output depends upon the rate of change of the input; e.g., it will display changes in amplitude but will reduce the duration of the waveform.
invisible d. SYN: chemodifferentiation.
pressure pulse d. the processing of a pressure pulse signal so that the output depends upon the rate of change of the input, yielding dP/dt (pressure) or, for noninvasively recorded pulses, dD/dt (rate of change of displacement).

diffluence
diffluence (dif′loo-ens)

The process of becoming fluid. [L. dif-fluo, to flow in different directions, dissolve]

diffraction
diffraction (di-frak′shun)

Deflection of the rays of light from a straight line in passing by the edge of an opaque body or in passing an obstacle of about the size of the wavelength of the light. [L. dif- fringo, pp. -fractus, to break in pieces]

diffraction grating
diffraction grating

A variety of filter composed of lined grooves in a thin layer of aluminum-copper alloy on a glass surface; used in spectrophotometers to disperse light into a spectrum. See monochromator.

diffusate
diffusate (di-fu′zat)

SYN: dialysate. [L. dif-fundo, pp. -fusus, to pour in different directions]

diffuse
diffuse (di-fus)

1. (di-fuz′)To disseminate; to spread about. 2. (di-fus′)Disseminated; spread about; not restricted. [L. dif-fundo, pp. -fusus, to pour in different directions]

diffusible
diffusible (di-fuz′i-bl)

Capable of diffusing.

diffusion
diffusion (di-fu′zhun)

1. The random movement of molecules or ions or small particles in solution or suspension under the influence of brownian (thermal) motion toward a uniform distribution throughout the available volume; the rate is relatively rapid among liquids and gases, but takes place very slowly among solids. 2. Light scattering.
facilitated d. See facilitated transport.
gel d. d. in a gel, as in the case of gel d. precipitin tests in which the immune reactants diffuse in agar. SEE ALSO: immunodiffusion.
passive d. See facilitated transport.

diflorasone diacetate
diflorasone diacetate (di-flor′a-son)

An anti-inflammatory corticosteroid used in topical preparations.

diflucortolone
diflucortolone (di-floo-kor′ti-lon)

A synthetic glucocorticoid steroid analog.

diflunisal
diflunisal (di-floo′ni-saul)

A salicyclic acid derivative with anti-inflammatory, analgesic, and antipyretic actions used in chronic disorders such as rheumatoid arthritis and osteoarthritis.

digametic
digametic (di-ga-met′ik)

SYN: heterogametic.

digastric
digastric (di-gas′trik)

1. Having two bellies; denoting especially a muscle with two fleshy parts separated by an intervening tendinous part. SYN: biventral. See d. (muscle). 2. Relating to the d. muscle; denoting a fossa or groove with which it is in relation and a nerve supplying its posterior belly. SYN: digastricus (1) . [G. di-, two, + gaster, belly]

digastricus
digastricus (di-gas′tri-kus)

1. SYN: digastric. 2. Denoting the musculus d.. [L.]

Digenea
Digenea (di-je′ne-a)

Subclass of parasitic flatworms (class Trematoda) characterized by a complex life cycle involving developmental multiplying stages in a mollusk intermediate host, an adult stage in a vertebrate, and often involving an additional transport host or an additional intermediate host; includes all of the common flukes of humans and other mammals. [G. di-, two, + genesis, generation]

digenesis
digenesis (di-jen′e-sis)

Reproduction in distinctive patterns in alternate generations, as seen in the nonsexual (invertebrate) and the sexual (vertebrate) cycles of digenetic trematode parasites. [G. di-, two, + G. genesis, generation]

digenetic
digenetic (di-je-net′ik)

1. Pertaining to or characterized by digenesis. SYN: heteroxenous. 2. Pertaining to the d. fluke.

DiGeorge
DiGeorge

Angelo M., U.S. pediatrician, *1921. See D. syndrome.

digest
digest

1. (di-jest′, di-)To soften by moisture and heat. 2. (di-jest′, di-)To hydrolyze or break up into simpler chemical compounds by means of hydrolyzing enzymes or chemical action, as in the action of the secretions of the alimentary tract upon food. 3. (di′jest)The materials resulting from digestion or hydrolysis. [L. digero, pp. -gestus, to force apart, divide, dissolve]

digestant
digestant (di-jes′tant, di-)

1. Aiding digestion. 2. An agent that favors or assists the process of digestion. SYN: digestive (2) .

digestion
digestion (di-jes′chun, di-)

1. The process of making a digest. 2. The mechanical, chemical, and enzymatic process whereby ingested food is converted into material suitable for assimilation for synthesis of tissues or liberation of energy. [L. digestio. See digest]
buccal d. that part of d. carried on in the mouth; E.G., the action of salivary amylases.
duodenal d. that part of d. carried on in the duodenum.
gastric d. that part of d., chiefly of the proteins, carried on in the stomach by the enzymes of the gastric juice. SYN: peptic d..
intercellular d. d. in a cavity by means of secretions from the surrounding cells, such as occurs in the metazoa.
intestinal d. that part of d. carried on in the intestine; it affects all the foodstuffs: starches, fats, and proteins.
intracellular d. d. within the boundaries of a cell, such as occurs in the protozoa and in phagocytes.
pancreatic d. d. in the intestine by the enzymes of the pancreatic juice.
peptic d. SYN: gastric d..
primary d. d. in the alimentary tract.
salivary d. the conversion of starch into sugar by the action of salivary amylase.
secondary d. the change in the chyle effected by the action of the cells of the body, whereby the final products of d. are assimilated in the process of metabolism.

digestive
digestive (di-jes′tiv, di-)

1. Relating to digestion. 2. SYN: digestant (2) .

digit
digit (dij′it) [TA]

A finger or toe. SEE ALSO: finger, toe. SYN: digitus [TA] , dactyl, dactylus. [L. digitus]
binary d. SYN: bit.
clubbed d. clubbing.
digits of foot toe.
primary d. of foot SYN: great toe I.

digital
digital (dij′i-tal)

Relating to or resembling a digit or digits or an impression made by them; based on numeric methodology.

digitalin
digitalin (dij-i-tal′in)

A standardized mixture of digitalis glycosides used as a cardiotonic in the treatment of congestive heart failure.
crystalline d. SYN: digitoxin.

Digitalis
Digitalis (dij-i-tal′is, -ta′lis)

A genus of perennial flowering plants of the family Schrophulariaceae. D. lanata, a European species, and D. purpurea, purple foxglove, are the main sources of cardioactive steroid glycosides used in the treatment of certain heart diseases, especially congestive heart failure; also used to treat tachyarrhythmias of atrial origin. SYN: foxglove. [L. d., relating to the fingers; in allusion to the fingerlike flowers]

digitalism
digitalism (dij′i-tal-izm)

The symptoms caused by digitalis poisoning or overdosage.

digitalization
digitalization (dij′i-tal-i-za′shun)

Administration of digitalis by any one of a number of schedules until sufficient amounts are present in the body to produce the desired therapeutic effects.

digitate
digitate (dij′i-tat)

Marked by a number of fingerlike processes or impressions. [L. digitatus, having fingers, fr. digitus, finger]

digitation
digitation (dij-i-ta′shun)

A process resembling a finger. [Mod. L. digitatio]

digitationes hippocampi
digitationes hippocampi (dij-i-ta-she-o′nez hip-o-kam′pe)

SYN: foot of hippocampus. [Mod. L. pl. of digitatio]

digiti
digiti (dij′i-ti)

Plural of digitus. [L.]

digitin
digitin (dij′i-tin)

SYN: digitonin.

digitonin
digitonin (dij-i-to′nin)

1. A steroid glycoside obtained from Digitalis purpurea that has no cardiac action; used as a reagent in the determination of plasma cholesterol and steroids having a 3-hydroxyl group in beta configuration. 2. A mixture of four different steroids found in the seeds of Digitalis purpurea; a strong hemolytic poison. They can act as nonionic detergents in the solubilization of membrane proteins. SYN: digitin.

digitoxigenin
digitoxigenin (dij′i-toks′i-jen-in)

The aglycon derived from digitoxin; can be prepared by refluxing digitoxin in a mixture of water, alcohol, and hydrochloric acid.

digitoxin
digitoxin (dij-i-tok′sin)

A cardioactive glycoside obtained from the leaves of Digitalis purpurea; it is more completely absorbed from the gastrointestinal tract than is digitalis. Largely eliminated by hepatic metabolism. SYN: crystalline digitalin.

digitoxose
digitoxose (dij′i-toks′os)

The sugar moiety obtained by mild acid hydrolysis of the glycosides digitoxin, gitoxin, and digoxin. The hydrolysis yields 3 moles of d. for each mole of the respective aglycon.

d-digitoxose
d-digitoxose (dij′i-toks′os)

The carbohydrate moiety found in digitalis glycosides; 2,6-dideoxy-d-ribo-hexose.

digitus
digitus, pl .digiti (dij′i-tus, -ti) [TA]

SYN: digit. [L.]
d. anularis [TA] SYN: ring finger.
d. auricularis SYN: little finger.
digiti hippocratici obsolete term for clubbed digits or fingers. See clubbing.
d. manus [TA] SYN: finger.
d. (manus) medius [TA] SYN: middle finger.
d. (manus) minimus [TA] SYN: little finger.
d. (manus) primus thumb.
d. (manus) quartus IV ring finger.
d. (manus) quintus [V] SYN: little finger.
d. (manus) secundus [II] index finger.
d. (manus) tertius [III] middle finger.
d. pedis [TA] SYN: toe.
d. (pedis) minimus [V] [TA] SYN: little toe [V].
d. pedis primus I great toe I.
d. (pedis) quartus [IV] [TA] SYN: fourth toe [IV].
d. (pedis) quintus [V] little toe [V].
d. (pedis) secundus [II] [TA] SYN: second toe [II].
d. (pedis) tertius [III] [TA] SYN: third toe [III].
d. valgus permanent deviation of one or more fingers to the radial side.
d. varus permanent deviation of one or more fingers to the ulnar side.

diglossia
diglossia (di-glos′e-a)

A developmental condition that results in a longitudinal split in the tongue. See bifid tongue. [G. di-, two, + glossa, tongue]

diglyceride lipase
diglyceride lipase (di-glis′er-id)

SYN: lipoprotein lipase.

diglycocoll hydroiodide-iodine
diglycocoll hydroiodide-iodine (di-gli′ko-kol hi-dro-i′o-did-i′o-din)

Two moles of diglycocoll hydroiodide combined with two atomic weights of iodine; an antibacterial agent used in tablet form to disinfect drinking water.

dignathus
dignathus (di-nath′us)

A malformed fetus with a double mandible. SYN: augnathus. [G. di-, two, + gnathos, jaw]

digoxigenin
digoxigenin (di-joks′i-jen-in)

The aglycon of digoxin that is joined by 3 moles of digitoxose to form the glycoside, digoxin.

digoxin
digoxin (di-jok′sin)

A cardioactive steroid glycoside obtained from Digitalis lanata. Largely eliminated by the kidneys.

Di Guglielmo
Di Guglielmo

Giovanni, Italian physician, 1886–1961. See D. disease, D. syndrome.

digyny
digyny, digynia (di′ji-ne, di-jin′e-a)

Fertilization of a diploid ovum by a sperm, which results in a triploid zygote. Cf.:diandry. [di- + G. gyne, woman]

diheterozygote
diheterozygote (di-het′er-o-zi′got)

An individual heterozygous at two loci of interest, especially in genetic linkage analysis.

dihybrid
dihybrid (di-hi′brid)

The offspring of parents differing in two characters. [G. di-, two, + L. hybrida, offspring of a tame sow and a wild boar]

dihydralazine
dihydralazine (di-hi-dral′a-zen)

An antihypertensive agent.

dihydrate
dihydrate (di-hi′drat)

A compound with two molecules of water of crystallization.

dihydrazone
dihydrazone (di-hi′dra-zon)

SYN: osazone.

dihydro- dihydro-

Prefix indicating the addition of two hydrogen atoms. [G. di, two + hydor, water]

dihydroascorbic acid
dihydroascorbic acid (di-hi′dro-as-kor′bik)

SYN: l-gulonolactone.

dihydrobiopterin
dihydrobiopterin (di-hi′dro-bi-op′ter-in)

Precursor to tetrahydrobiopterin, a required cofactor for a number of enzymes, including the biosynthesis of l-tyrosine; the inability to synthesize d. can result in a form of malignant hyperphenylalaninemia.
d. reductase SYN: dihydropteridine reductase.

dihydrocodeine tartrate
dihydrocodeine tartrate (di-hi-dro-ko′den)

An analgesic derivative of codeine, about one-sixth as potent as morphine; a narcotic antitussive.

dihydrocodeinone
dihydrocodeinone (di-hi-dro-ko′den-on)

SYN: hydrocodone.

dihydrocortisone
dihydrocortisone (di-hi-dro-kor′ti-son)

A metabolite of cortisone, reduced at the 4,5 double bond.

dihydroergocornine
dihydroergocornine (di-hi′dro-er-go-kor′nin)

An ergot alkaloid derivative prepared by the hydrogenation of ergocornine and less toxic than the latter. See dihydroergotoxine mesylate.

dihydroergocristine
dihydroergocristine (di-hi′dro-er-go-kris′ten)

An ergot alkaloid derivative prepared by the hydrogenation of ergocristine and less toxic than the latter. See dihydroergotoxine mesylate.

dihydroergocryptine
dihydroergocryptine (di-hi′dro-er-go-krip′ten)

An ergot alkaloid derivative prepared by the hydrogenation of ergocryptine and less toxic than the latter. See dihydroergotoxine mesylate.

dihydroergotamine
dihydroergotamine (di-hi′dro-er-got′a-men)

An ergot alkaloid derivative prepared by the hydrogenation of ergotamine; used in the treatment of migraine; less toxic and less oxytocic than ergotamine.

dihydroergotoxine mesylate
dihydroergotoxine mesylate (di-hi′dro-er-go-tok′sen)

A mixture of dihydroergocornine methanesulfate, dihydroergocristine methanesulfate, and dihydroergocryptine methane sulfate; used as an α-adrenergic blocking agent for relief of cardiovascular insufficiency.

dihydrofolate reductase
dihydrofolate reductase (DHFR) (di-hi-dro-fo′lat)

An enzyme reversibly oxidizing tetrahydrofolate to 7,8-dihydrofolate with NADP⁺. A crucial enzyme in one-carbon metabolism; used as a marker of drug resistance to methotrexate. SYN: 5,6,7,8-tetrahydrofolate dehydrogenase.

7,8-dihydrofolic acid
7,8-dihydrofolic acid (di-hi-dro-fo′lik)

Intermediate between folic acid and 5,6,7,8-tetrahydrofolic acid, oxidation of the latter requiring NADP⁺ and dehydrofolate reductase.

dihydrogen
dihydrogen

SYN: hydrogen (2) .

dihydrolipoamide S-acetyltransferase
dihydrolipoamide S-acetyltransferase (di-hi′dro-lip-o-am′id a-se-til-trans′fer-az)

An enzyme catalyzing the transfer of an acetyl grout from S⁶-acetyldihydrolipoamide to coenzyme A. A part of many enzyme complexes ( e.g., pyruvate dehydrogenase complex). SYN: lipoate acetyltransferase, thioltransacetylase A.

dihydrolipoamide dehydrogenase
dihydrolipoamide dehydrogenase (di-hi′dro-lip-o-am′id di-hi-dro′jen-az)

A flavoenzyme oxidizing dihydrolipoamide at the expense of NAD⁺; completes the oxidative decarboxylation of pyruvate; a part of several enzyme complexes ( e.g., α-ketoglutarate dehydrogenase complex). Decreased activity leads to neuronal loss in brain resulting in psychomotor retardation. SYN: coenzyme factor, lipoamide dehydrogenase, lipoamide reductase (NADH), lipoyl dehydrogenase.

dihydrolipoic acid
dihydrolipoic acid (di-hi′dro-lip-o′ik)

Reduced lipoic acid, formed by cleavage of the &cbond;S&cbond;S&cbond; bond as a result of the acceptance of two hydrogens. Cf.:lipoic acid.

dihydromorphinone hydrochloride
dihydromorphinone hydrochloride (di-hi-dro-mor′fi-non)

SYN: hydromorphone hydrochloride.

dihydro-orotase
dihydro-orotase (di-hi′dro-or-o′tas)

An enzyme catalyzing ring closure of N-carbamoyl-l-aspartate to form l-5,6-dihydroorotate and water; an enzyme in pyrimidine biosynthesis. SYN: carbamoylaspartate dehydrase.

dihydro-orotate
dihydro-orotate (di-hi′dro-or-o′tat)

l-5,6-Dihydroorotate;an intermediate in the biosynthesis of pyrimidines.

dihydropteridine reductase
dihydropteridine reductase

An enzyme that catalyzes the reversible formation of tetrahydrobiopterin from dihydrobiopterine using NADPH; a deficiency of this enzyme can result in malignant hyperphenylalaninemia. SYN: dihydrobiopterin reductase.

dihydropteroic acid
dihydropteroic acid (di-hi′dro-te-ro′ik)

An intermediate in the formation of folic acid; a compound of 6-hydroxymethylpterin and p-aminobenzoic acid, the combining of which is inhibited by sulfonamides.

dihydropyrimidine dehydrogenase
dihydropyrimidine dehydrogenase (di-hi-dro′pi-rim′i-den de-hi-dro′jen-as)

An enzyme in pyrimidine biosynthesis that reacts 5,6-dihydrouracil with NADP⁺ to form uracil and NADPH; it also acts on dihydrothymine; a deficiency of this enzyme can result in hyperuracil thyminuria. SYN: dihydrouracil dehydrogenase.

dihydrostreptomycin
dihydrostreptomycin (di-hi′dro-strep-to-mi′sin)

An aminoglycoside antibiotic similar in action to streptomycin but with a higher risk of ototoxicity.

dihydrotachysterol
dihydrotachysterol (di-hi′dro-ta-kis′ter-ol)

See tachysterol.

dihydrotestosterone
dihydrotestosterone (di-hi′dro-tes-tos′ter-on)

SYN: stanolone.

dihydrouracil
dihydrouracil (di-hi-dro-ur′a-sil)

5,6-D.;a reduction product of uracil and one of the intermediates of uracil catabolism.

dihydrouracil dehydrogenase
dihydrouracil dehydrogenase

SYN: dihydropyrimidine dehydrogenase.

dihydrouridine
dihydrouridine (hU, hu, D) (di-hi-dro-ur′i-den)

Uridine in which the 5,6-double bond has been saturated by addition of two hydrogen atoms; a rare constituent of transfer ribonucleic acids.

dihydroxy- dihydroxy-

Prefix denoting addition of two hydroxyl groups; as a suffix, becomes -diol.

dihydroxyacetone
dihydroxyacetone (di′hi-drok-se-as′e-ton)

HOCH₂–CO–CH₂OH; 1,3-dihydroxy-2-propanone;glycerone; the simplest ketose. SYN: glycerulose.
d. phosphate (DHAP) one of the intermediates in the glycolytic pathway and in fat biosynthesis; glycerone phosphate.
d. phosphate acyltransferase an enzyme that catalyzes an important step in plasmalogen biosynthesis; an acyl group from acyl-CoA is transferred to d. phosphate producing free coenzyme A and 1-acyldihydroxyacetone phosphate.

2,8-dihydroxyadenine
2,8-dihydroxyadenine (di-hi-drok′se-ad′e-nen)

An insoluble minor product of adenine catabolism that is elevated in individuals with an absence of adenine phosphoribosyltransferase.

dihydroxyaluminum aminoacetate
dihydroxyaluminum aminoacetate (di-hi-drok′se-a-loo′mi-num am′i-no-as′e-tat)

Basic aluminum glycinate, a basic aluminum salt of aminoacetic acid containing small amounts of aluminum hydroxide and aminoacetic acid; used as an antacid in hyperchlorhydria and peptic ulcer.

dihydroxyaluminum sodium carbonate
dihydroxyaluminum sodium carbonate

A gastric antacid.

1,25-dihydroxyergocalciferol
1,25-dihydroxyergocalciferol (di-hi-drok′se-er′go-kal-sif′er-ol)

A biologically active metabolite of vitamin D₂. SYN: ercalcitriol.

3,4-dihydroxyphenylalanine
3,4-dihydroxyphenylalanine (di-hi-droks′e-fen-il-al′a-nen)

SYN: dopa.

diiodide
diiodide (di-i′o-did)

A compound containing two atoms of iodine per molecule.

diiodo- diiodo-

Prefix indicating two atoms of iodine. [G. di, + ioeides, violet flower color]

diiodohydroxyquin
diiodohydroxyquin (di-i-o′do-hi-drok′si-kwin)

C₉H₅I₂NO;an antiprotozoal agent, used in the treatment of intestinal amebiasis. SYN: diodoquin.

diiodotyrosine
diiodotyrosine (DIT) (di′i-o-do-ti′ro-sen)

An intermediate in the biosynthesis of thyroid hormone.

diisopromine
diisopromine (di-i-so-pro′men)

A cholagogue. SYN: disopromine.

diisopropyl fluorophosphate
diisopropyl fluorophosphate (DFP) (di-i-so-pro′pil flor-o-fos′fat)

SYN: isofluorphate.

diisopropyl iminodiacetic acid
diisopropyl iminodiacetic acid (DISIDA) (di-e-so-pro′pil im′i- no-di-a-se-tik)

A radiopharmaceutical labeled with ^99mTc, used for cholescintigraphy. SYN: disofenin.

2,6-diisopropyl phenol
2,6-diisopropyl phenol

SYN: propofol.

2,3-diketo-l-gulonate
2,3-diketo-l-gulonate

A product of catabolism of vitamin C; formed from l-dehydroascorbate; it has no vitamin C activity.

diketohydrindylidene-diketohydrindamine
diketohydrindylidene-diketohydrindamine (di-ke′to-hi-drin-dil′i-den di-ke′to-hi-drind′a-men)

The colored product formed in the reaction of an α-amino acid and ninhydrin (triketohydrindene hydrate); a reaction used in the quantitative assay of α-amino acids.

diketone
diketone (di-ke′ton)

A molecule containing two carbonyl groups; e.g., acetylacetone (CH₃COCH₂COCH₃).

diketopiperazines
diketopiperazines (di-ke′to-pi-per′a-zenz)

A class of organic compounds with a closed ring structure formed from two α-amino acids by the joining of the α-amino group of each to the carboxyl group of the other, with the loss of two molecules of water.

dil.
dil.

Abbreviation for L. dilue, dilute, or L. dilutus, diluted.

dilaceration
dilaceration (di-las-er-a′shun)

Displacement of some portion of a developing tooth which is then further developed in its new relation, resulting in a tooth with sharply angulated root(s). [L. di-lacero, pp. laceratus, to tear in pieces, fr. lacer, mangled]

dilatancy
dilatancy (di-la′tan-se)

An increasing viscosity with increasing rate of shear accompanied by volumetric expansion. [L. dilato, to dilate]

dilatation
dilatation (dil-a-ta′shun)

SYN: dilation.
digital d. use of the finger or finger-tip to enlarge an orifice or opening, such as enlarging the orifice of a sclerosed mitral valve surgically.

dilatator
dilatator (dil′a-ta-ter, -tor)

SYN: dilator.

dilate
dilate (di′lat)

To perform or undergo dilation.

dilation
dilation (di-la′shun)

1. Physiologic or artificial enlargement of a hollow structure or opening. 2. The act of stretching or enlarging an opening or the lumen of a hollow structure. SYN: dilatation. [L. dilato, pp. dilatatus, to spread out, dilate]
d. and extraction a form of abortion in which the cervix is dilated and the fetus extracted in pieces using surgical forceps; technique used to complete a second trimester spontaneous abortion or as a form of induced abortion.
post-stenotic d. d. of an artery, most commonly the pulmonary artery or the aorta, distal to an area of narrowing.
d. and suction SYN: suction curettage.
urethral d. increasing the caliber of the urethra by passage of a dilator.

dilation and curettage
dilation and curettage (D & C)

Dilation of the cervix and curettement of the endometrium.

dilation and evacuation
dilation and evacuation (D & E)

Dilation of the cervix and removal of the products of conception.

dilator
dilator (di′la-ter)

1. An instrument designed for enlarging a hollow structure or opening. 2. A muscle that pulls open an orifice. 3. A substance that causes dilation or enlargement of an opening or the lumen of a hollow structure. SEE ALSO: bougie. SYN: dilatator.
Chevalier-Jackson d. an esophageal d. that passes through a rigid endoscope.
Hanks dilators uterine dilators of solid metal construction.
Hegar dilators a series of cylindrical bougies of graduated sizes used to dilate the cervical canal.
hydrostatic d. an instrument for dilating esophageal strictures; fluid pressure is delivered into a flexible area of the instrument placed in the stricture to establish a uniform dilating pressure.
d. iridis SYN: d. pupillae muscle.
Kollmann d. a metallic expandable instrument used to dilate urethral strictures.
pneumatic d. any of a variety of catheters fitted with distal balloons that can be inflated to desired pressures for overcoming obstructions in hollow viscera; most often used to rupture the lower esophageal sphincter to treat achalasia.
Pratt dilators cylindrical metal rods of graduated sizes used to dilate the cervical canal.
d. of pupil SYN: d. pupillae muscle.
Walther d. a gently curved instrument that tapers to an increased diameter, used to dilate the female urethra.

dildo
dildo, dildoe (dil′do)

An artificial penis; an object having the approximate shape and size of an erect penis, and commonly made of wood, plastic, or rubber; utilized for sexual pleasure.

dilemma
dilemma

masking d. a problem encountered in establishing the bone conduction thresholds in severe bilateral conductive hearing loss, in which the amount of masking of the nontest ear exceeds the interaural attenuation so that enough masking is too much masking.

dill oil
dill oil

A volatile oil distilled from the fruit of Anethum graveolens (family Umbelliferae); a carminative.

diloxanide furoate
diloxanide furoate (di-lok′sa-nid fu′ro-at)

An amebicide used in the treatment of dysentery.

diltiazem hydrochloride
diltiazem hydrochloride (dil-ti′a-zem)

A calcium channel blocking agent used as a coronary vasodilator, an antiarrhythmic, and antihypertensive.

diluent
diluent

1. Ingredient in a medicinal preparation that lacks pharmacologic activity but is pharmaceutically necessary or desirable. In tablet or capsule dosage forms, this may be lactose or starch; it is particularly useful in increasing the bulk of potent drug substances whose mass is too small for dosage form manufacture or administration. May be a liquid for the dissolution of drug(s) to be injected, ingested, or inhaled. 2. Denoting that which dilutes; the diluting agent.

dilute
dilute (dil.) (di-loot′)

1. To reduce a solution or mixture in concentration, strength, quality, or purity. 2. Diluted; denoting a solution or mixture so effected. [L. di-luo, to wash away, d.]

dilution
dilution (di-loo′shun)

1. The act of being diluted. 2. A diluted solution or mixture. 3. In microbiologic techniques, a method for counting the number of viable cells in a suspension; a sample is diluted to the point where an aliquot, when plated, yields a countable number of separate colonies.

dim.
dim.

Abbreviation for L. dimidius, one-half.

dimazole dihydrochloride
dimazole dihydrochloride (di′ma-zol)

SYN: diamthazole dihydrochloride.

dimazon
dimazon (di-ma′zon)

An azo compound occurring in red crystals; used with petrolatum as an ointment to stimulate epithelial cell proliferation and thus promote the healing of superficial wounds.

dimelia
dimelia (di-me′le-a)

Congenital duplication of the whole or a part of a limb. [G. di-, two, + melos, limb]

dimenhydrinate
dimenhydrinate (di-men-hi′dri-nat)

The 8-chlorotheophylline salt of the antihistamine, diphenhydramine; used for the prevention of motion sickness, as an antihistamine and mild sedative. Also used in the treatment of Parkinson disease, as it has appreciable anticholinergic properties.

dimension
dimension (di-men′shun)

Scope, size, magnitude; denoting, in the plural, linear measurements of length, width, and height.
buccolingual d. the diameter or d. of a premolar or molar tooth from buccal to lingual surface.
occlusal vertical d. the vertical d. of the face when the teeth or occlusion rims are in contact in centric occlusion; decrease in occlusal vertical d. may result from modification of tooth form by attrition or grinding, drifting of teeth, or, in edentulous patients, by resorption of residual ridges; increase may result from modifications of tooth form, tooth position, height of occlusion rims, rebasing or relining, or occlusal splints.
rest vertical d. the vertical d. of the face with the jaws in rest relation; decrease in rest vertical d. may or may not accompany a decrease in occlusal vertical d.; it may occur without a decrease in occlusal vertical d. in patients with a preponderant activity of the jaw-closing musculature, as in patients with muscular hypertenseness or in chronic gum chewers; increase in rest vertical d. may or may not accompany an increase in occlusal vertical d.; it sometimes occurs after the removal of remaining occlusal contacts, perhaps as a result of the removal of noxious reflex stimuli.
vertical d. a vertical measurement of the face between any two arbitrarily selected points which are conveniently located, one above and one below the mouth, usually in the midline. SYN: vertical opening.

dimer
dimer (di′mer)

A compound or unit produced by the combination of two like molecules; in the strictest sense, without loss of atoms (thus nitrogen tetroxide, N₂O₄, is the d. of nitrogen dioxide, NO₂), but usually by elimination of H₂O or a similar small molecule between the two ( e.g., a disaccharide), or by simple noncovalent association (as of two identical protein molecules); higher orders of complexity are called trimers, tetramers, oligomers, and polymers. [G. di-, two, + -mer]
pyrimidine d. a product of ultraviolet radiation of pyrimidines in nucleic acids; most frequently thymidine dimers.
thymine d. a product of ultraviolet irradiation of thymine (free in ice or bound in nucleic acids) in which two thymine residues become linked by formation of a cyclobutane ring involving both C-5's and both C-6's at the expense of the two double bonds; several stereoisomeric forms are possible.

dimercaprol
dimercaprol (di-mer-kap′rol)

A chelating agent, developed as an antidote for lewisite and other arsenical poisons. It acts by competing for the metal with the essential —SH groups in the pyruvate oxidase system of the cells and forms, with arsenic, a stable, relatively nontoxic cyclic compound, the metal having a greater affinity for it than for the —SH groups of the cell proteins; also used as an antidote for antimony, bismuth, chromium, mercury, gold, and nickel. SYN: antilewisite, British anti-Lewisite.

dimercurion
dimercurion (di-mer′kur-i′on)

The mercuric ion, Hg²⁺.

dimeric
dimeric (di′mer-ik)

Having the characteristics of a dimer.

dimerous
dimerous (dim′er-us)

Consisting of two parts. [G. di-, two, + meros, part]

dimetacrine tartrate
dimetacrine tartrate (di-met′a-kren)

An antidepressant.

dimethadione
dimethadione (di-meth-a-di′on)

The active metabolite formed by the N-demethylation of trimethadione, an oxazolidinedione type antiepileptic agent. Can be used for in vivo measurement of intracellular pH.

dimethicone
dimethicone (di-meth′i-kon)

A silicone oil consisting of dimethylsiloxane polymers, usually incorporated into a petrolatum base or a nongreasy preparation and used for the protection of normal skin against various, chiefly industrial, skin irritants; may also be used to prevent diaper dermatitis.

dimethindene maleate
dimethindene maleate (di-meth′in-den)

An antihistamine also used as an antipruritic.

dimethisterone
dimethisterone (di-me-this′ter-on)

A modified testosterone or ethisterone; an orally effective synthetic progestin used alone or in combination with ethynyl estradiol as a contraceptive agent.

dimethothiazine mesylate
dimethothiazine mesylate (di-meth-o-thi′a-zen)

SYN: fonazine mesylate.

dimethoxanate hydrochloride
dimethoxanate hydrochloride (di′me-thok′sa-nat)

A non-narcotic antitussive agent, less effective than codeine.

dimethoxyamphetamine
dimethoxyamphetamine (DMA)

A hallucinogen with properties resembling lysergic acid diethylamide (LSD).

2,5-dimethoxy-4-methylamphetamine
2,5-dimethoxy-4-methylamphetamine (DOM)

An hallucinogenic agent chemically related to amphetamine and mescaline, a drug of abuse.

dimethylallylpyrophosphate
dimethylallylpyrophosphate (di-meth′il-al′lil-pi′ro -fos′fat)

An intermediate in steroid and terpene biosynthesis.

dimethylaminoazobenzene
dimethylaminoazobenzene (di-meth′il-a-me-no-az-o-ben′zen) [C.I. 11160]

SYN: butter yellow.

dimethylarsinic acid
dimethylarsinic acid (di-meth′il-ar-sin′ik)

SYN: cacodylic acid.

dimethylbenzene
dimethylbenzene (di-meth-il-ben′zen)

SYN: xylol.

5,6-dimethylbenzimidazole
5,6-dimethylbenzimidazole (di-meth′il-benz-e-mid-a-zol)

A structural moiety found in one of the cobalamins.

dimethylcarbinol
dimethylcarbinol (di-meth-il-kar′bi-nol)

SYN: isopropyl alcohol.

dimethyl-1-carbomethoxy-1-propen-2-yl phosphate
dimethyl-1-carbomethoxy-1-propen-2-yl phosphate

An organic phosphorus compound used as a systemic poison for the extermination of such pests as mites, aphids, and houseflies.

dimethyl iminodiacetic acid
dimethyl iminodiacetic acid (HIDA) (di-meth′il im′i-no-di-a-se-tik)

A radiopharmaceutical labeled with ^99mTc, an early agent used for cholescintigraphy.

dimethyl ketone
dimethyl ketone (di-meth′il ke′ton)

SYN: acetone.

dimethylmercury
dimethylmercury (di-meth-il-mer′ku-re)

A contaminant of seafood products synthesized in sediments from mercury and mercury-containing chemicals dumped in waters supporting marine life. The methylmercury is concentrated in aquatic life forms and can thus be deposited in fishes intended for human consumption. Probable cause of Minimata disease, a teratogenic condition characterized by multiple birth defects. An inorganic reagent. SEE ALSO: Minamata disease. SYN: methylmercury.

dimethylphenol
dimethylphenol (di-meth-il-fe′nol)

SYN: xylenol.

dimethylphenylpiperazinium
dimethylphenylpiperazinium (DMPP) (di-meth′il-fen′il-pi-par-a-zin′e-um)

A highly selective stimulant of autonomic ganglionic cells; used experimentally.

dimethyl phthalate
dimethyl phthalate (di-meth′il thal′at)

An insect repellent.

dimethylpiperazine tartrate
dimethylpiperazine tartrate (di-meth′il-pi-par′a-zen)

A diuretic, also used as a uric acid solvent.

dimethyl sulfate
dimethyl sulfate

An industrial chemical (sulfuric acid dimethyl ester (CH₃)₂SO₄), used in synthesis as an alkylating agent; it causes nystagmus, convulsions, and death from pulmonary complications.

dimethyl sulfoxide
dimethyl sulfoxide (DMSO) (di-meth′il)

Me₂SO;a penetrating solvent, enhancing absorption of therapeutic agents from the skin; an industrial solvent that has been proposed as an effective analgesic and anti-inflammatory agent in arthritis and bursitis.

dimethyl d-tubocurarine
dimethyl d-tubocurarine

SYN: metocurine iodide.

dimethyl tubocurarine chloride
dimethyl tubocurarine chloride

Dimethyl ether of d-tubocurarine chloride; a skeletal muscle relaxant. See tubocurarine chloride.

dimethyl tubocurarine iodide
dimethyl tubocurarine iodide

SYN: metocurine iodide.

dimetria
dimetria (di-me′tre-a)

Obsolete term for uterus didelphys. [G. di-, two, + metra, womb]

Dimmer
Dimmer

Friedrich, Austrian ophthalmologist, 1855–1926. See D. keratitis.

dimorphic
dimorphic (di-mor′fik)

1. In fungi, a term referring to growth and reproduction in two forms: mold and yeast. SYN: dimorphous (2) . 2. SYN: dimorphous (1) .

dimorphism
dimorphism (di-mor′fizm)

1. Existence in two shapes or forms; denoting a difference of crystalline form exhibited by the same substance, or a difference in form or outward appearance between individuals of the same species ( e.g., sexual d.). 2. The occurrence in plants of two distinct forms of leaves or other parts in the same individual plant. [G. di-, two, + morphe, shape]
sexual d. the somatic differences within species between male and female individuals that arise as a consequence of sexual maturation; inclusive of, but not restricted to, the secondary sexual characters.

dimorphous
dimorphous (di-mor′fus)

1. Having the property of dimorphism. SYN: dimorphic (2) . 2. SYN: dimorphic (1) .

dimple
dimple (dim′pl)

1. A natural indentation, usually circular and of small area, in the chin, cheek, or sacral region. 2. A depression of similar appearance to a d., resulting from trauma or the contraction of scar tissue. 3. To cause dimples.
coccygeal d. SYN: coccygeal foveola.
postanal d. SYN: coccygeal foveola.

dimpling
dimpling

1. Causing dimples. 2. A condition marked by the formation of dimples, natural or artificial.

dineric
dineric (di-ner′ik)

Denoting the interface between two mutually immiscible liquids ( e.g., oil and water) in the same container. [di- + G. neron, water]

dinitrocellulose
dinitrocellulose (di-ni-tro-sel′u-los)

SYN: pyroxylin.

4,6-dinitro-o-cresol
4,6-dinitro-o-cresol

An insecticide used against mites in the form of a spray or dust; also used as a weed killer.

dinitrogen monoxide
dinitrogen monoxide (di-ni′tro-jen)

SYN: nitrous oxide.

2,4-dinitrophenol
2,4-dinitrophenol (DNP, Dnp) (di-ni-tro-fe′nol)

N₂pH-OH;a toxic dye, chemically related to trinitrophenol (picric acid), used in biochemical studies of oxidative processes where it uncouples oxidative phosphorylation; it is also a metabolic stimulant.

dinoflagellate
dinoflagellate (di′no-flaj′e-lat)

A plantlike flagellate of the subclass Phytomastigophorea, some species of which ( e.g., Gonyaulax cantanella) produce a potent neurotoxin that may cause severe food intoxication following ingestion of parasitized shellfish. [G. dinos, whirling, + L. flagellum, a whip]

Dinoflagellida
Dinoflagellida

An order in the phylum Sareomastigophorea characterized by the presence of two flagella so placed as to cause the organism to have a whirling motility. Its outer surface is composed of cellulose-containing plates whose size and number vary with genus and species.

dinoprost
dinoprost (di′no-prost)

An oxytocic agent. SYN: prostaglandin F_2α.
d. tromethamine an oxytocic agent. SYN: prostaglandin F_2α tromethamine.

dinoprostone
dinoprostone (di-no-pros′ton)

An oxytocic agent used as an abortifacient. SYN: prostaglandin E₂.

dinucleotide
dinucleotide (di-noo′kle-o-tid)

A compound containing two nucleotides; E.G., NAD⁺, ApGp.

Dioctophyma
Dioctophyma (di-ok-to-fi′ma)

A genus of very large nematode worms infecting the kidney. [L. fr. G. dionkoo, to distend, + phyma, growth]
D. renale a large blood-red nematode found in the pelvis of the kidney and the peritoneal cavity of the dog; fairly common in wild carnivores like the mink, but rarely found in humans; the life cycle is via leeches ectoparasitic on crayfish, which are then eaten by various fishes and finally by humans or any of a number of other mammalian fish-eating hosts.

dioctophymiasis
dioctophymiasis (di-ok′to-fi-mi′a-sis)

Infection of animals and rarely humans with the giant kidney worm, Dioctophyma renale.

dioctyl calcium sulfosuccinate
dioctyl calcium sulfosuccinate (di-ok′til kal′se-um sul-fo-suk′si-nat)

SYN: docusate calcium.

dioctyl sodium sulfosuccinate
dioctyl sodium sulfosuccinate

SYN: docusate sodium.

Diodon
Diodon (di′o-don)

A genus of porcupine fishes related to balloon fish, globefish, and puffers. Although the common puffer is widely eaten as “sea squab” in the United States, many puffers, especially in the Pacific, are poisonous because of the presence of a neurotoxin, tetrodotoxin, in the liver and ovary. [G. di-, two, + odous (odont-), tooth]

diodone
diodone (di′o-don)

SYN: iodopyracet.

diodoquin
diodoquin (di-o′do-kwin)

SYN: diiodohydroxyquin.

Diogenes
Diogenes

Of Sinope, Greek philosopher, 412–323 B.C. See D. cup, poculum diogenis.

-diol -diol (di′ol)

1. Suffix form of the prefix dihydroxy. 2. A member of a class of compounds containing two hydroxyl groups.
gym-diol, gym-diol a compound in which both hydroxyl groups are attached to the same carbon atom; an intermediate in many reactions.

diolamine
diolamine (di-ol′a-men)

USAN-approved contraction for diethanolamine.

diopter
diopter (D) (di-op′ter)

The unit of refracting power of lenses, denoting the reciprocal of the focal length expressed in meters. [G. dioptra, a leveling instrument]
prism d. (p.d.) the unit of measurement of the deviation of light in passing through a prism, being a deflection of 1 cm at a distance of 1 m.

dioptrics
dioptrics (di-op′triks)

The branch of optics concerned with the refraction of light.

dioscin
dioscin (di-os-in)

A steroid saponin found in yams (Dioscorea) and trilliums.

diose
diose (di′os)

SYN: glycolaldehyde.

diosgenin
diosgenin (di′os-jen′in)

The aglycon of dioscing a sapogenin derived from the saponins dioscin and trillin found in the roots of plants such as the yam; its steroid portion serves as a source from which pregnenolone and progesterone can be prepared.

diotic
diotic (di-ot′ik)

Simultaneous presentation of the same sound to each ear. [di- + otic]

diovular
diovular (di′ov-u-lar)

Relating to two ova. SYN: biovular. [di- + Mod. L. ovulum, dim. of L. ovum, egg]

diovulatory
diovulatory (di-o′vu-la-to′re)

Releasing two ova in one ovarian cycle.

dioxane
dioxane (di-oks′an)

1,4-D.;a colorless liquid used as a solvent for cellulose esters and in histology as a drying agent. SYN: 1,4-diethylene dioxide.

dioxide
dioxide (di-oks′id)

A molecule containing two atoms of oxygen; e.g., carbon d., CO₂.

dioxin
dioxin (di-oks′in)

1. A ring consisting of two oxygen atoms, four CH groups, and two double bonds; the positions of the oxygen atoms are specified by prefixes, as in 1,4-d.. 2. Abbreviation for dibenzo[b,e][1,4]d. which may be visualized as an anhydride of two molecules of 1,2-benzenediol (pyrocatechol), thus forming two oxygen bridges between two benzene moieties, or as a 1,4-d. with a benzene ring fused to catch each of the two CH&dbond;CH groups. 3. A contaminant in the herbicide, 2,4,5-T; it is potentially toxic, teratogenic, and carcinogenic.

dioxybenzone
dioxybenzone (di-ok-se-ben′zon)

An ultraviolet screen for topical application to the skin.

dioxygenase
dioxygenase (di-oks′e-jen-as)

An oxidoreductase that incorporates two atoms of oxygen (from one molecule of O₂) into the (reduced) substrate.

D.I.P.
D.I.P.

Abbreviation for desquamative interstitial pneumonia.

dip
dip

1. A downward inclination or slope. 2. A preparation for coating a surface by submersion, as for the destruction of skin parasites. [M.E. dippen]
Cournand d. in constrictive pericarditis, rapid early diastolic fall and reascent of the ventricular pressure curve to an elevated plateau (square root configuration).

dipeptidase
dipeptidase (di-pep′ti-das)

A hydrolase catalyzing the hydrolysis of a dipeptide to its constituent amino acids.
methionyl d. a hydrolase catalyzing the hydrolysis of an l-methionyl-amino acid to l-methionine and an amino acid.

dipeptide
dipeptide (di-pep′tid)

A combination of two amino acids by means of a peptide (–CO–NH–) link.

dipeptidyl carboxypeptidase
dipeptidyl carboxypeptidase (di-pep′ti-dil)

SYN: peptidyl dipeptidase A.

dipeptidyl peptidase
dipeptidyl peptidase

A hydrolase occurring in a number of forms: d. I, dipeptidyl transferase, cleaving dipeptides from the amino end of polypeptides; d. II, with properties similar to those of I, has a different specificity and acts preferably on tripeptides; d. III acts on longer peptides.

dipeptidyl transferase
dipeptidyl transferase

Cleaving dipeptides from the amino end of polypeptides. See dipeptidyl peptidase.

Dipetalonema
Dipetalonema (di-pet′a-lo-ne′ma)

A genus of nematode filariae with species in humans and many other mammals; as with other filarial worms, it produces microfilariae in blood or tissue fluids, with adults found in deep connective tissue, membranes, or visceral surfaces. [G. di-, two, + petalon, leaf, + nema, thread]
D. reconditum a filarial species found in dogs, transmitted by fleas and lice, in contrast to the canine heartworm, Dirofilaria immitis, which is transmitted by mosquitoes.
D. streptocerca former name for Mansonella streptocerca.

diphallus
diphallus (di-fal′us)

A rare congenital anomaly in which the penis is partly or completely duplicated; may be symmetrical, or placed one above the other; often there are associated urogenital or other anomalies; occurs when two genital tubercles develop. May also be associated with exstrophy of the urinary bladder and splitting of the genital tubercle. SYN: bifid penis. [G. di-, two, + phallos, penis]

diphasic
diphasic (di-fa′zik)

Occurring in or characterized by two phases or stages.

diphemanil methylsulfate
diphemanil methylsulfate (di-fe′ma-nil)

An anticholinergic agent.

diphemethoxidine
diphemethoxidine (di-fem-e-thok′si-den)

An anorexigenic drug.

diphenadione
diphenadione (di-fen-a-di′on)

An orally effective anticoagulant with actions and uses similar to those of bishydroxycoumarin.

diphenan
diphenan (di′fen-an, di-fen′an)

Used as a vermicide in oxyuriasis.

diphenhydramine hydrochloride
diphenhydramine hydrochloride (di-fen-hi′dra-men)

An H₂ antihistaminic with anticholinergic and sedative properties.

diphenidol
diphenidol (di-fen′i-dol)

An antiemetic.

diphenol oxidase
diphenol oxidase (di-fen′ol)

SYN: catechol oxidase.

diphenoxylate hydrochloride
diphenoxylate hydrochloride (di-fen-ok′si-lat)

An antidiarrheal agent, chemically related to meperidine, that inhibits rhythmic contraction of smooth muscle; it has modest addiction liability. Similar to loperamide.

diphenyl
diphenyl (di-fen′il)

Colorless liquid; used as heat transfer agent, frequently as polychlorinated biphenyls (PCBs); as fungistat for oranges (applied to inside of shipping container or wrappers); and in organic syntheses. Produces convulsions and central nervous system depression. SYN: biphenyl, phenylbenzene.

diphenyl- diphenyl-

Prefix denoting two independent phenyl groups attached to a third atom or radical, as in diphenylamine.

diphenylchlorarsine
diphenylchlorarsine (di-fen′il-klor-ar′sen)

A sternutator, inhalation of which causes violent sneezing, cough, salivation, headache, and retrosternal pain; a common vomiting agent used in mob and riot control.

diphenylcyanoarsine
diphenylcyanoarsine (di-fen′il-si-an-o-ar-sen)

A common vomiting agent used for mob and riot control.

diphenylenimine
diphenylenimine (di′fen-il-en′i-men)

SYN: carbazole.

diphenylhydantoin
diphenylhydantoin (di′fen-il-hi-dan′to-in)

See phenytoin.

5,5-diphenylhydantoin
5,5-diphenylhydantoin (di-fen′il-hi-dan′to-in)

SYN: phenytoin.

2,5-diphenyloxazole
2,5-diphenyloxazole (PPO) (di′fen-il-oks′a-zol)

A scintillator used in radioactivity measurements by liquid scintillation counting.

diphenylpyraline hydrochloride
diphenylpyraline hydrochloride (di-fen-il-pir′a-len)

An H₁ antihistaminic similar in action and use to diphenhydramine.

diphosgene
diphosgene (di-fos′jen)

A poison gas used in World War I; it is also slightly lacrimatoric.

diphosphatase
diphosphatase (di-fos′fa-taz)

SYN: pyrophosphatase.
inorganic d. SYN: inorganic pyrophosphatase.

diphosphate
diphosphate

SYN: pyrophosphate.

diphosphothiamin
diphosphothiamin (di′fos-fo-thi′a-min)

SYN: thiamin pyrophosphate.

diphtheria
diphtheria (dif-the-r′ea)

A specific infectious disease due to the bacterium Corynebacterium diphtheriae and its highly potent toxin; marked by severe inflammation that can form a membranous coating, with formation of a thick fibrinous exudate, of the mucous membrane of the pharynx, the nose, and sometimes the tracheobronchial tree; the toxin produces degeneration in peripheral nerves, heart muscle, and other tissues, d. had a high fatality rate, especially in children, but now rare because of an effective vaccine. [G. diphthera, leather]
cutaneous d. a &dquor;punched-out&dquor; shallow ulcer sometimes bordered or followed by a bulla, resulting from infection of the skin by Corynebacterium diphtheriae; systemic manifestations are the same as those of pharyngeal d..
false d. SYN: diphtheroid (1) .
faucial d. severe pharyngitis affecting the fauces, the usual site affected by infection with Corynebacterium diphtheriae.
laryngeal d. d. affecting the larynx, usually with asphyxiation due to obstruction of the airway by the membrane that forms, with fatal outcome. SYN: laryngotracheal d..
laryngotracheal d. SYN: laryngeal d..

diphtherial
diphtherial, diphtheritic (dif-the-r′e-al, dif-the-rit′ik)

Relating to diphtheria, or the membranous exudate characteristic of this disease. SYN: diphtheric.

diphtheric
diphtheric

SYN: diphtherial.

diphtheroid
diphtheroid (dif′the-royd)

1. One of a group of local infections suggesting diphtheria, but caused by microorganisms other than Corynebacterium diphtheriae. SYN: Epstein disease, false diphtheria, pseudodiphtheria. 2. Any microorganism resembling Corynebacterium diphtheriae. [diphtheria + G. eidos, resemblance]

diphtherotoxin
diphtherotoxin (dif′ther-o-tok′sin)

The toxin of diphtheria.

diphyllobothriasis
diphyllobothriasis (di-fil′o-both-ri′a-sis)

Infection with the cestode Diphyllobothrium latum; human infection is caused by ingestion of raw or inadequately cooked fish infected with the plerocercoid larva. Leukocytosis and eosinophilia may occur; if the worm is high enough in the alimentary canal, it may preempt the supply of vitamin B₁₂ or alter its absorption, leading to hyperchromic macrocytic anemia resembling pernicious anemia, although the condition is rare, even in hyperendemic areas. SYN: bothriocephaliasis.

Diphyllobothrium
Diphyllobothrium (di-fil-lo-both′re-um)

A large genus of tapeworms (order Pseudophyllidea) characterized by a spatulate scolex with dorsal and ventral sucking grooves or bothria. Several species are found in humans, although only one, D. latum, is of widespread importance. [G. di-, two, + phyllon, leaf, + bothrion, little ditch]
D. cordatum a species found in dogs, sea mammals, and occasionally humans, in Greenland.
D. dendriticum adult form of the tapeworm found in the intestine of fish-eating birds; infective for humans.
D. hians tapeworm species found in humans in Japan.
D. houghtoni canine and feline tapeworm; found in humans in China.
D. latum the broad or broad fish tapeworm, a species that causes diphyllobothriasis, found in humans and fish-eating mammals in many parts of northern Europe, Japan and elsewhere in Asia, and in Scandinavian populations of the American north central states; it often has 3 or 4 thousand segments, broader than long; the head has typical bothria characteristic of the genus. SYN: Dibothriocephalus latus.
D. linguloides SYN: Spirometra mansoni.
D. mansoni SYN: Spirometra mansoni.
D. mansonoides SYN: Spirometra mansonoides.
D. nihonkaiense tapeworm species closely related to D. latum; found in Japan with increasing numbers of human infections.
D. orcini tapeworm species found in humans in Japan.
D. pacificum tapeworm species found in sea lions; has been described as a human tapeworm acquired from marine fishes; found in Japan, Peru, and Ecuador.
D. scoticum tapeworm species found in humans in Japan.

diphyodont
diphyodont (di-f′e-o-dont)

Possessing two sets of teeth, as occurs in humans and most other mammals. [G. di-, two, + phyo, to produce, + odous (odont-), tooth]

dipiproverine
dipiproverine (di-pi-pro′ver-en)

An intestinal antispasmodic.

dipivefrin hydrochloride
dipivefrin hydrochloride (di-piv′e-frin)

An adrenergic epinephrine prodrug used in drop form in initial therapy for control of intraocular pressure in chronic open-angle glaucoma.

diplacusis
diplacusis (dip-la-koo′sis)

Abnormal perception of sound, either in time or in pitch, so that one sound is heard as two. [G. diplous, double, + akousis, a hearing]
d. binauralis a condition in which the same sound is heard differently by the two ears.
d. dysharmonica a condition in which the same sound is heard as a different pitch in each ear.
d. echoica a condition in which sound heard in the affected ear is repeated.
d. monauralis a condition in which one sound is perceived as two in the same ear.

diplegia
diplegia (di-ple′je-a)

Paralysis of corresponding parts on both sides of the body. SYN: double hemiplegia. [G. di-, two, + plege, a stroke]
congenital facial d. SYN: Möbius syndrome.
facial d. paralysis of both sides of the face.
infantile d. SYN: spastic d..
masticatory d. paralysis of all the muscles of mastication.
spastic d. a type of cerebral palsy in which there is bilateral spasticity, with the lower extremities more severely affected. Cf.:flaccid paralysis. SYN: Erb-Charcot disease (1) , infantile d., Little disease, spastic spinal paralysis.

diplo- diplo-

Double, twofold. See haplo-. [G. diploos, double]

diploalbuminuria
diploalbuminuria (dip′lo-al-bu-mi-noo′re-a)

The coexistence of nephritic, or pathologic, and nonnephritic, or physiologic, albuminuria.

diplobacillus
diplobacillus (dip′lo-ba-sil′us)

Two rod-shaped bacterial cells linked end to end. [diplo- + bacillus]

diploblastic
diploblastic (dip-lo-blas′tik)

Formed of two germ layers. [diplo- + G. blastos, germ]

diplocardia
diplocardia (dip-lo-kar′de-a)

An anomaly in which the left and right halves of the heart are separated to varying degrees by a central fissure. [diplo- + G. kardia, heart]

diplocephalus
diplocephalus (dip-lo-sef′a-lus)

SYN: dicephalus.

diplocheiria
diplocheiria, diplochiria (dip′lo-ki′re-a)

SYN: dicheiria. [diplo- + G. cheir, hand]

diplococcemia
diplococcemia (dip-lo-kok-se′me-a)

The presence of diplococci in the blood; used especially in referring to Neisseria meningitidis (meningococci) in circulating blood.

diplococci
diplococci (dip′lo-kok′si)

Plural of diplococcus.

diplococcin
diplococcin (dip-lo-kok′sin)

An antibiotic crystalline substance isolated from cultures of lactic acid-producing cocci present in milk active against lactobacilli and certain Gram-positive cocci, but inactive against Gram-negative bacteria.

Diplococcus
Diplococcus (dip′lo-kok′us)

Species of this former genus of bacteria are now assigned to other genera. D. pneumoniae, the type species of D., is a member of the genus Streptococcus. See Neisseria, Peptococcus, Streptococcus. [diplo- + G. kokkos, berry]

diplococcus
diplococcus, pl .diplococci (dip′lo-kok′us, -kok′si)

1. Spherical or ovoid bacterial cells joined together in pairs. 2. Common name of any organism belonging to the former bacterial genus D.. [diplo- + G. kokkos, berry]

diplocoria
diplocoria (dip-lo-ko′re-a)

The occurrence of two pupils in the eye. SYN: dicoria. [diplo- + G. kore, pupil]

diploë
diploë (dip′lo-e) [TA]

The central layer of spongy bone between the two layers of compact bone, outer and inner plates, or tables, of the flat cranial bones. [G. diploe, fem. of diplous, double]

diplogenesis
diplogenesis (dip-lo-jen′e-sis)

Production of a double fetus or of one with some parts doubled. [diplo- + G. genesis, production]

Diplogonoporus
Diplogonoporus (dip′lo-go-nop′o-rus)

A genus of tapeworms found in Japan (D. grandis) and probably also in Rumania (D. brauni) [diplo- + G. gonos, seed, + poros, pore]

diploic
diploic (dip-lo′ik)

Relating to the diploë.

diploid
diploid (dip′loyd)

Denoting the state of a cell containing two haploid sets derived from the father and from the mother respectively; the normal chromosome complement of somatic cells (in humans, 46 chromosomes). [diplo- + G. eidos resemblance]

diplokaryon
diplokaryon (dip′lo-kar′e-on)

A cell nucleus containing four haploid sets; i.e., a tetraploid nucleus. SEE ALSO: polyploidy. [diplo- + G. karyon, nut (nucleus)]

diplomelituria
diplomelituria (dip′lo-mel-i-too′re-a)

The occurrence of diabetic and nondiabetic glycosuria in the same individual. [diplo- + G. meli, honey, + ouron, urine]

diplomyelia
diplomyelia (dip-lo-mi-e′le-a)

Complete or incomplete doubling of the spinal cord; may be accompanied by a bony septum of the vertebral canal. [diplo- + G. myelon, marrow]

diplon
diplon (dip′lon)

SYN: deuteron.

diplonema
diplonema (dip-lo-ne′ma)

The doubled form of the chromosome strand visible at the diplotene stage of meiosis. [diplo- + G. nema, thread]

diploneural
diploneural (dip-lo-noo′ral)

Supplied by two nerves from different sources, said of certain muscles. [diplo- + G. neuron, nerve]

diplopagus
diplopagus (dip-lop′a-gus)

General term for conjoined twins, each with fairly complete bodies, although one or more internal organs may be in common. See conjoined twins, under twin. [diplo- + G. pagos, something fixed]

diplopia
diplopia (di-plo′pe-a)

The condition in which a single object is perceived as two objects. SYN: double vision. [diplo- + G. ops, eye]
crossed d. d. in which the image seen by the right eye is to the left of the image seen by the left eye. SYN: heteronymous d..
heteronymous d. SYN: crossed d..
homonymous d. SYN: homonymous images, under image.
monocular d. a double image or an extra ghost image produced in one eye, almost always by an aberration of the ocular media; for example, a corneal or lenticular irregularity, an uncorrected astigmatism or an irregularity of the vitreous or the retina. If a similar process occurs in both eyes (bilateral monocular d.), that is, the doubling is still present with either eye covered, the patient may still only see two images; seeing multiple images (polyopia) is rare.
simple d. SYN: homonymous images, under image.
uncrossed d. SYN: homonymous images, under image.

diplopodia
diplopodia (dip-lo-po′de-a)

Duplication of digits of the foot. [diplo- + G. pous, foot]

diplosome
diplosome (dip′lo-som)

Paired allosomes; the pair of centrioles of mammalian cells. SYN: paired allosome. [diplo- + G. soma, body]

diplosomia
diplosomia (dip-lo-so′me-a)

Condition in which twins who seem functionally independent are joined at one or more points. See conjoined twins, under twin. [diplo- + G. soma, body]

diplotene
diplotene (dip′lo-ten)

The late stage of prophase in meiosis in which the paired homologous chromosomes begin to repel each other and move apart, but are usually held together by chiasmata. The chiasmata are associated with breakage of two chromatids at corresponding points followed by refusion of the broken ends with exchange of segments between the chromatids; this is considered to be the cytologic basis for the crossing-over of genes. [diplo- + G. tainia, band]

dipodia
dipodia (di-po′de-a)

1. A developmental anomaly involving complete or incomplete duplication of a foot. 2. In conjoined twins and sirenomelia, a degree of union leaving two feet evident. [G. di-, two, + pous (pod-), foot]

dipole
dipole (di′pol)

A pair of separated electrical charges, one or more positive and one or more negative; or a pair of separated partial charges. SYN: doublet (2) .

dipotassium phosphate
dipotassium phosphate (di-po-tas′e-um)

SYN: potassium phosphate.

diprenorphine
diprenorphine (di-pren′or-fen)

A narcotic antagonist resembling naloxone but more potent.

dipropyltryptamine
dipropyltryptamine (di-pro-pil-trip′ta-men)

A hallucinogenic agent similar to dimethyltryptamine.

diprosopus
diprosopus (di-pros′o-pus, di-pro-so′pus)

Conjoined twins with almost complete fusion of the bodies and with normal limbs. Part or all of the face may be duplicated. See conjoined twins, under twin. [G. di-, two + prosopon, face]

dipsesis
dipsesis (dip-se′sis)

An abnormal or excessive thirst, or a craving for unusual forms of drink. SYN: dipsosis, morbid thirst. [G. dipseo, to thirst]

dipsogen
dipsogen (dip′so-jen)

A thirst-provoking agent. [G. dipsa, thirst, + -gen, producing]

dipsomania
dipsomania (dip-so-ma′ne-a)

A recurring compulsion to drink alcoholic beverages to excess. See alcoholism. [G. dipsa, thirst, + mania, madness]

dipsosis
dipsosis (dip-so′sis)

SYN: dipsesis. [G. dipsa, thirst, + -osis, condition]

dipsotherapy
dipsotherapy (dip′so-thar′a-pe)

Treatment of certain diseases by abstention, as far as possible, from liquids.

Diptera
Diptera (dip′ter-a)

An important order of insects (the two-wing flies and gnats), including many significant disease vectors such as the mosquito, tsetse fly, sandfly, and biting midge. [G. di-, two, + pteron, wing]

dipteran
dipteran (dip′ter-an)

Denoting insects of the order Diptera.

dipterous
dipterous (dip′ter-us)

Relating to or characteristic of the order Diptera.

Dipus sagitta
Dipus sagitta (di′pus saj′i-ta)

A small rodent of southern Russia that serves as a vector, through fleas, of Yersinia pestis (plague bacillus). [G. dipous, jerboa, two-footed; L. sagitta, arrow]

dipygus
dipygus (di-pi′gus, dip′e-gus)

Conjoined twins with a single head and thorax and the pelvis and lower extremities duplicated; when the duplications of the lower parts are symmetric, usually called duplicitas posterior. See conjoined twins, under twin. [G. di-, two, + pyge, buttocks]

dipylidiasis
dipylidiasis (dip′i-li-di′a-sis)

Infection of carnivores and humans with the cestode Dipylidium caninum.

Dipylidium caninum
Dipylidium caninum (dip-i-lid′e-um ka-ni′num)

The commonest species of dog tapeworm, the double-pored tapeworm, the larvae of which are harbored by dog fleas or lice; the worm occasionally infects humans, especially children licked by dogs that have recently nipped infected fleas. [G. dipylos, with two entrances; L. ntr. of caninus, pertaining to canis, dog]

dipyridamole
dipyridamole (di-pir-id′a-mol)

A coronary vasodilator that also has a weak action to reduce platelet aggregation; commonly used in place of exercise for studies of myocardial contractility.

dipyrimidine photolyase
dipyrimidine photolyase (di-pi-rim′i-den)

SYN: deoxyribodipyrimidine photolyase.

dipyrine
dipyrine (di-pi′ren)

SYN: aminopyrine.

dipyrone
dipyrone (di-pi′ron)

An analgesic, anti-inflammatory, and antipyretic agent rarely used because of a high incidence of agranulocytosis. SYN: methampyrone.

directive
directive

advance d. a legal document giving instructions as to the type and degree of medical care to be administered in the event that the person signing the document becomes mentally incompetent during the course of a terminal illness, or becomes permanently comatose (persistent vegetative state).State legislatures have enacted so-called Death with Dignity laws to protect the rights of patients to refuse medical care, including life-prolonging and palliative care in terminal illness, as well as to clarify the role of physicians and indemnify them against the accusation of euthanasia or physician-assisted suicide when they withhold such care in compliance with patients' wishes. These laws spell out strict procedural requirements, including the need for the signing of an advance d. to be duly witnessed, and make it easier to revoke an advance d. than to establish one. When an advance d. provides instructions for the types of care the patient does or does not want to receive, it is known as a living will. When it names another person to make such decisions, it is known as a durable power-of-attorney for health care decisions. An advance d. can contain both types of instruction. An agent making end-of-life decisions on behalf of a patient is required to follow the patient's instructions, interpreting them when necessary in the light of the patient's personal philosophy, religious beliefs, and ethical values, and with due consideration for the likelihood that the patient will regain competency or will recover.

director
director (di-rek′ter, -tor, di-)

1. A smoothly grooved instrument used with a knife to limit the incision of tissues. SYN: staff (2) . 2. The head of a service or specialty division. [L. dirigo, pp. -rectus, to arrange, set in order]

Dirofilaria
Dirofilaria (di-ro-fi-la′re-a)

A genus of filaria (family Onchocercidae, superfamily Filarioidea); D. species are usually found in mammals other than man, but rare examples of human infection are known, as by D. immitis. [L. dirus, dread, + filum, thread]
D. conjunctivae name assigned to filarial worms removed from tumors and abscesses in various sites in human cases, especially palpebral conjunctivae and other eye tissues, but also subcutaneous tissues from other sites; probably caused by a number of species of animal origin.
D. immitis a species of filarial worms of dogs and other canids in tropical and subtropical areas, found chiefly in the right ventricle and pulmonary arteries of dogs; sometimes a serious pathogen of racing and show dogs, especially in the southern U.S. where mosquito vectors are common; D. immitis and its canine host have been used to test chemotherapeutic agents, and an extract of D. immitis may be used as a nonspecific intradermal antigen in the diagnosis of human filariasis and in complement-fixation tests. SEE ALSO: Dipetalonema reconditum. SYN: heartworm.

dirofilariasis
dirofilariasis (dir′o-fil-a-ri′a-sis)

Infection of animals and, rarely, humans with nematodes of the genus Dirofilaria.

dirt-eating
dirt-eating

SYN: geophagia.

dis- dis-

In two, apart; un-, not; very. Cf.:dys-. [L. separation]

disability
disability (dis-a-bil′i-te)

1. According to the “International Classification of Impairments, Disabilities and Handicaps” (World Health Organization), any restriction or lack of ability to perform an activity in a manner or within the range considered normal for a human being. The term d. reflects the consequences of impairment in terms of functional performance and activity by the individual; disabilities thus represent disturbances at the level of the person. 2. An impairment or defect of one or more organs or members.
developmental d. loss of function brought on by prenatal and postnatal events in which the predominant disturbance is in the acquisition of cognitive, language, motor, or social skills; e.g., mental retardation, autistic disorder, learning disorder, and attention-deficit hyperactivity disorder.
learning d. a disorder in one or more of the basic cognitive and psychological processes involved in understanding or using written or spoken language; may be manifested in age-related impairment in the ability to read, write, spell, speak, or perform mathematical calculations.

disaccharidases
disaccharidases (di-sak′a-rid-as-ez)

A group of enzymes that catalyze the hydrolysis of disaccharides, producing two monosaccharides.

disaccharide
disaccharide (di-sak′a-rid)

A condensation product of two monosaccharides by elimination of water (usually between an alcoholic OH and a hemiacetal OH); e.g., sucrose, lactose, maltose.

disaggregation
disaggregation (dis′ag-gre-ga′shun)

1. A breaking up into component parts. 2. An inability to coordinate various sensations and failure to comprehend their mutual relations. [L. dis-, separating, + ag- grego (adg-), pp. -gregatus, to add to something]

disarticulation
disarticulation (dis-ar-tik-u-la′shun)

Amputation of a limb through a joint, without cutting of bone. [L. dis-, apart, + articulus, joint]

disassimilation
disassimilation (dis′a-sim-i-la′shun)

Destructive or retrograde metabolism. SYN: dissimilation (1) .

disassociation
disassociation (dis′a-so-se-a′shun)

SYN: dissociation (1) .

disc
disc (disk)

See disk.

disc- disc-

See disco-.

discectomy
discectomy (disk-ek′to-me)

Excision, in part or whole, of an intervertebral disk. SYN: discotomy. [disco- + G. ektome, excision]

discharge
discharge (dis′charj)

1. That which is emitted or evacuated, as an excretion or a secretion. 2. The activation or firing of a neuron.
after-d. afterdischarge.
early d. d. of a woman and the newborn from the hospital within 24 hours of a vaginal delivery.

Dische
Dische

Zacharias, 20th century Austrian-U.S. biochemist, 1895–1988. See D. reaction, D. reagent, D.-Schwarz reagent.

dischronation
dischronation (dis-kro-na′shun)

A disturbance in the consciousness of time. [L. dis-, apart, + G. chronos, time]

disci
disci (dis′ki)

Plural of discus.

disciform
disciform (dis′i-form)

Disk-shaped.

discission
discission (di-sish′un)

1. Incision or cutting through a part. 2. In ophthalmology, opening of the capsule and breaking up of the cortex of the lens with a needle knife or laser. [L. di- scindo, pp. -scissus, to tear asunder]

discitis
discitis (dis-ki′tis)

Inflammation of an intervertebral disk or disk space often related to infections. SYN: diskitis.

disco- disco-, disc-

A disk; disk-shaped. [G. diskos]

discoblastic
discoblastic (dis-ko-blas′tik)

Denoting a discoblastula.

discoblastula
discoblastula (dis′ko-blas′tu-la)

A blastula of the type produced by the meroblastic discoidal cleavage of a large-yolked ovum.

discogastrula
discogastrula (dis′ko-gas′troo-la)

A gastrula of the type formed after the discoidal cleavage of a large-yolked ovum.

discogenic
discogenic (dis′ko-gen′ik)

Denoting a disorder originating in or from an intervertebral disk. [disco- + G. genesis, origin]

discoid
discoid (dis′koyd)

1. Resembling a disk. 2. In dentistry, an excavating or carving instrument having a circular blade with a cutting edge around the periphery. [disco- + G. eidos, appearance]

disconjugate
disconjugate (dis-con′joo-gat)

Not paired in action or joined together; the opposite of conjugate. See d. movement of eyes. [L. dis-, apart, + jugatus, yoked]

discopathy
discopathy (dis-kop′a-the)

Disease of a disk, particularly of an invertebral disk. [disco- + G. pathos, disease]
traumatic cervical d. an injury characterized by fissuration, laceration and/or fragmentation of a cervical disk or surrounding ligaments, with or without displacement of fragments against spinal cord, nerve roots, or ligaments.

discoplacenta
discoplacenta (dis-ko-pla-sen′ta)

A placenta of discoid shape.

discordance
discordance (dis-kor′dans)

1. Dissociation of two characteristics in the members of a sample from a population; used as a measure of dependence. 2. In genetics, the presence of a given trait in only one member of a twin pair. Cf.:concordance.

discotomy
discotomy (dis-kot′o-me)

SYN: discectomy. [disco- + G. tome, incision]

discrete
discrete (dis-kret′)

Separate; distinct; not joined to or incorporated with another; denoting especially certain lesions of the skin. [L. dis- cerno, pp. -cretus, to separate]

discrimination
discrimination (dis′krim-i-na′shun)

In conditioning, responding differentially, as when an organism makes one response to a reinforced stimulus and a different response to an unreinforced stimulus. [L. discrimino, pp. -atus, to separate]

discus
discus, pl .disci (dis′kus, -ki) [TA]

SYN: lamella (2) . [L. fr. G. diskos, a quoit, disk]
d. articularis [TA] SYN: articular disk.
d. articularis acromioclavicularis [TA] SYN: articular disk of acromioclavicular joint.
d. articularis radioulnaris distalis [TA] SYN: articular disk of distal radioulnar joint.
d. articularis sternoclavicularis [TA] SYN: articular disk of sternoclavicular joint.
d. articularis temporomandibularis [TA] SYN: articular disk of temporomandibular joint.
d. interpubicus [TA] SYN: interpubic disk.
d. intervertebralis [TA] SYN: intervertebral disk.
d. lentiformis rarely used term for subthalamic nucleus.
d. nervi optici [TA] SYN: optic disk.
d. proligerus the attachment point of the cumulus oöphorus to the most peripheral granulosa cells of an antral follicle.

disdiaclast
disdiaclast (dis-di′a-klast)

A doubly refractive element in striated muscular tissue. [G. dis, twice, + dia, through, + klastos, broken]

disease
disease (di-zez′)

1. An interruption, cessation, or disorder of body function, system, or organ. SYN: illness, morbus, sickness. 2. A morbid entity characterized usually by at least two of these criteria: recognized etiologic agent(s), identifiable group of signs and symptoms, or consistent anatomic alterations. SEE ALSO: syndrome. 3. Literally, dis-ease, the opposite of ease, when something is wrong with a bodily function. [Eng. dis- priv. + ease]
aaa d. endemic anemia of ancient Egypt, ascribed in the Papyrus Ebers to intestinal infestation with ancylostoma; now called ancylostomiasis.
ABO hemolytic d. of the newborn erythroblastosis fetalis due to maternal-fetal incompatibility with respect to an antigen of the ABO blood group; the fetus possesses A or B antigen which is lacking in the mother, and the mother produces immune antibody which causes hemolysis of fetal erythrocytes.
accumulation d. a d. characterized by abnormal accumulation of a metabolic product in certain cells and tissues; examples include the mucopolysaccharidoses, lipoidoses.
Acosta d. SYN: altitude sickness.
Adams-Stokes d. SYN: Adams-Stokes syndrome.
adaptation diseases diseases falling theoretically into Selye concept of the general-adaptation syndrome.
Addison d. SYN: chronic adrenocortical insufficiency.
Addison-Biermer d. SYN: pernicious anemia.
akamushi d. SYN: tsutsugamushi d..
Albers-Schönberg d. SYN: osteopetrosis.
Albright d. SYN: McCune-Albright syndrome.
Alexander d. a rare, fatal central nervous system degenerative d. of infants, characterized by psychomotor retardation, seizures, and paralysis; megaloencephaly is associated with widespread leukodystrophic changes, especially in the frontal lobes.
Almeida d. SYN: paracoccidioidomycosis.
Alpers d. SYN: poliodystrophia cerebri progressiva infantilis.
altitude d. SYN: altitude sickness.
Alzheimer d. a progressive degenerative d. of the brain that causes impairment of memory and dementia manifested by confusion, visual-spatial disorientation, inability to calculate, and deterioration of judgment; delusions and hallucinations may occur. The most common degenerative brain disorder, Alzheimer d. makes up 70% of all cases of dementia. Onset is usually in late middle life, and death typically ensues in 5–10 years. SYN: Alzheimer dementia, presenile dementia (2) , dementia presenilis, primary neuronal degeneration, primary senile dementia.Alzheimer d. (AD) ranks 4th as a cause of death in the U.S., and its annual cost to the nation is nearly $100 billion. Onset is typically insidious, with a progressive deterioration in the ability to learn and retain information. In recalling and repeating new material, the patient makes intrusion errors (insertion of irrelevant words or ideas) and resorts to confabulation. Orientation and judgment decline; 50% of patients experience depression, 20% delusions. Agitation occurs in 70%. Numerous drugs, including many not considered psychoactive, can aggravate the symptoms of AD; clinical depression can mask dementia, and vice versa. Behavioral disturbances are the major indications for the use of psychotropic drugs and physical restraints, and substantially influence the quality of life of demented elderly patients. Neurologic findings may be essentially normal, but myoclonus, bradykinesia, rigidity, and seizures can occur late in the d.. Death is usually due to sepsis associated with urinary or pulmonary infection. Atrophy of the cerebral cortex, with consequent enlargement of sulci and ventricles, may be grossly evident on imaging studies. Histologically the cortex, hippocampus, and amygdala show atrophy of neurons, with cytoplasmic vacuoles and argentophilic granules; distortion of intracellular neurofibrils (neurofibrillary tangles) due to excessive phosphorylation of microtubular tau proteins; and plaques composed of granular or filamentous argentophilic masses with a core of the 42-aminoacid form of β-amyloid (Aβ42). The concentration of tau protein in the cerebrospinal fluid is increased while that of Aβ42 is decreased. Lewy bodies (eosinophilic inclusions in the cytoplasm of CNS neurons, believed to be products of altered neurofilament metabolism and recognized as a hallmark of idiopathic parkinsonism) occur in cortical neurons of some persons with dementia, including AD. Dementia associated with Lewy bodies tends to appear before age 60, to progress rapidly, and to display parkinsonian features (tremor, rigidity). Nearly all persons with Down syndrome who live past the age of 40 develop cognitive decline associated with histologic findings typical of AD. Advancing age and a history of head injury are also risk factors for AD. Although most cases are sporadic, about 10% of patients have a family history of AD. Familial d., which is often characterized by early onset and rapid course, has been traced to mutations of several genes. At least half of all patients with early-onset familial AD show mutations in the presenilin-1 gene on chromosome 14. Mutations in the presenilin-2 gene on chromosome 1 or the amyloid precursor protein gene on chromosome 21 have been found in smaller kindreds with familial d.. Late-onset familial d. has been traced to mutations in an apolipoprotein E (APOE) locus on chromosome 19. All of these mutations are associated with increased production of Aβ42. It has been suggested that incorporation of presenilin proteins into neurons programs them for death through apoptosis. Cognitive decline in AD has been attributed in part to a deficiency of the neurotransmitter acetylcholine, and therapy with reversible cholinesterase inhibitors (donezepil, galanthamine, metrifonate, tacrine) has improved cognition and slowed progression of dementia in some patients. Numerous other agents (including nicotine, ginkgo extract, vitamin E, selegiline, ergoloid mesylates, and ibuprofen) have shown slight efficacy in some studies. Experimental evidence suggests that administration of estrogen to postmenopausal women retards onset and progression of nonfamilial AD.
anarthritic rheumatoid d. rheumatoid d. without arthritis.
Anders d. SYN: adiposis dolorosa.
Andersen d. SYN: type 4 glycogenosis.
antibody deficiency d. SYN: antibody deficiency syndrome.
aortoiliac occlusive d. obstruction of the abdominal aorta and its main branches by atherosclerosis.
Aran-Duchenne d. SYN: amyotrophic lateral sclerosis.
Australian X d. SYN: Murray Valley encephalitis.
autoimmune d. any disorder in which loss of function or destruction of normal tissue arises from humoral or cellular immune responses to the body's own tissue constituents; may be systemic, as systemic lupus erythematosus, or organ specific, as thyroiditis.
aviator's d. syndrome resembling decompression sickness occurring in occupants of airplanes that reach very high altitudes without adequate pressurization of the cabin. SEE ALSO: decompression sickness.
Ayerza d. SYN: Ayerza syndrome.
Azorean d. SYN: Machado-Joseph d..
Baelz d. SYN: cheilitis glandularis.
Baló d. SYN: encephalitis periaxialis concentrica.
Baltic myoclonus d. one of the familial light sensitive myoclonic epilepsies. Unlike Lafora body polymyoclonus, where inclusion bodies are seen in the brain cells, the prognosis is often favorable. Probably an autosomal recessive disorder.
Bamberger d. 1. SYN: saltatory spasm. 2. SYN: polyserositis.
Bamberger-Marie d. SYN: hypertrophic pulmonary osteoarthropathy.
Bang d. SYN: bovine brucellosis.
Banti d. SYN: Banti syndrome.
Barclay-Baron d. SYN: vallecular dysphagia.
Barlow d. SYN: infantile scurvy.
Barraquer d. SYN: progressive lipodystrophy.
Basedow d. SYN: Graves d..
Batten d. cerebral sphingolipidosis, late juvenile type. SYN: ceroid lipofuscinosis.
Batten-Mayou d. cerebral sphingolipidosis, late infantile and juvenile types.
Bazin d. SYN: erythema induratum.
Bechterew d. SYN: spondylitis deformans.
Becker d. an obscure South African cardiomyopathy leading to rapidly fatal congestive heart failure and idiopathic mural endomyocardial d..
Béguez César d. SYN: Chédiak-Higashi syndrome.
Behçet d. SYN: Behçet syndrome.
Behr d. SYN: Behr syndrome.
Berger d. SYN: focal glomerulonephritis.
Bernard-Soulier d. (ber-nar′-sool-ya) an autosomal recessive disorder of absent or decreased platelet membrane glycoproteins Ib, IX, and V (the receptor for factor VIII R). This deficiency can lead to a failure to bind von Willebrand factor, causing moderate bleeding.
Bernhardt d. SYN: meralgia paresthetica.
Besnier-Boeck-Schaumann d. SYN: sarcoidosis.
Best d. [MIM*153700] autosomal dominant macular degeneration beginning during the first years of life. SYN: vitelliform degeneration, vitelliform retinal dystrophy.
Bielschowsky d. early childhood type of lipofuscinosis.
Biermer d. SYN: pernicious anemia.
Binswanger d. one of the causes of multi-infarct dementia, in which there are many infarcts and lacunae in the white matter, with relative sparing of the cortex and basal ganglia. SYN: Binswanger encephalopathy, encephalitis subcorticalis chronica, subcortical arteriosclerotic encephalopathy.
bird-breeder's d. SYN: bird-breeder's lung.
blinding d. SYN: onchocerciasis.
Bloch-Sulzberger d. SYN: incontinentia pigmenti.
Blocq d. SYN: astasia-abasia.
Blount d. tibia vara; nonrachitic bowlegs in children. SYN: Blount-Barber d..
Blount-Barber d. SYN: Blount d..
blue d. SYN: Rocky Mountain spotted fever.
Boeck d. SYN: sarcoidosis.
Bornholm d. SYN: epidemic pleurodynia. [Bornholm, Danish island in the Baltic where the d. was first described]
Bosin d. SYN: subacute sclerosing panencephalitis.
Bouchard d. myopathic dilation of the stomach.
Bourneville d. SYN: tuberous sclerosis.
Bourneville-Pringle d. facial lesions with tuberous sclerosis, first reported as adenoma sebaceum, but now recognized as angiofibromas.
Bowen d. a form of intraepidermal carcinoma characterized by the development of slowly enlarging pinkish or brownish papules or eroded plaques covered with a thickened horny layer; microscopically, there is dyskeratosis with large round epidermal cells with large nuclei and pale-staining cytoplasm which are scattered through all levels of the epidermis. SYN: Bowen precancerous dermatosis.
Brailsford-Morquio d. SYN: Morquio syndrome.
brancher glycogen storage d. type of glycogen storage d., due to deficiency of amylo-1,4-1,6-transglucosidase (brancher enzyme). SYN: brancher deficiency glycogenosis, debrancher deficiency.
Breda d. SYN: espundia.
Bright d. nonsuppurative nephritis with albuminuria and edema, associated in fatal cases with large white kidneys; or with hematuria and red kidneys; or with contracted granular kidneys, corresponding to the stages of glomerulonephritis now termed subacute or membranous, acute, and chronic, respectively.
Brill d. SYN: Brill-Zinsser d..
Brill-Zinsser d. an endogenous reinfection associated with the “carrier state” in persons who previously had epidemic typhus fever; it is a rather mild d. and may be mistaken for endemic (murine) typhus; first described by Brill in New York City but not recognized as a recrudescent form of epidemic typhus until after the work of Zinsser. SYN: Brill d., recrudescent typhus fever, recrudescent typhus.
Briquet d. hysterical neurosis, conversion type.
Brissaud d. SYN: tic.
broad beta d. type III familial hyperlipoproteinemia.
Brodie d. 1. SYN: Brodie knee. 2. hysterical spinal neuralgia, simulating Pott d., following a trauma.
bronzed d. SYN: bronze diabetes. See hemochromatosis.
Bruck d. a d. marked by osteogenesis imperfecta, ankylosis of the joints, and muscular atrophy.
Brushfield-Wyatt d. a familial disorder characterized by unilateral nevus, contralateral hemiplegia, hemianopia, cerebral angioma, and mental retardation; possibly a variant of Sturge-Weber syndrome. SYN: nevoid amentia.
Buerger d. SYN: thromboangiitis obliterans.
bulging eye d. SYN: gedoelstiosis.
bulky d. term used for large tumors or lymph nodes; usually more resistant to conventional therapy. SYN: bulky lymphadenopathy.
Bürger-Grütz d. obsolete term for idiopathic hyperlipemia.
Buschke d. SYN: scleredema adultorum.
Busquet d. an osteoperiostitis of the metatarsal bones, leading to exostoses on the dorsum of the foot.
Byler d. [MIM*211600] progressive intrahepatic cholestasis, with early onset of loose, foul-smelling stools, jaundice, hepatosplenomegaly, dwarfism, and occasionally death; due to an error in conjugated bile salt metabolism; autosomal recessive inheritance, caused by mutation in the familial intrahepatic cholestasis 1 gene (FIC1) on chromosome 18q. [Byler, an Amish kindred]
Caffey d. SYN: infantile cortical hyperostosis.
caisson d. (ka′son) SYN: decompression sickness. [Fr. caisson (fr. caisse, a chest) a water-tight box or cylinder containing air under high pressure used in sinking structural pilings underwater]
calcium pyrophosphate deposition d. (CPPD) a crystal deposition arthritis that may simulate gout.
Calvé-Perthes d. SYN: Legg-Calvé-Perthes d..
Canavan d. [MIM*271900] progressive degenerative d. of infancy; mostly affecting Ashkenazi Jewish babies; onset typically within the first 3–4 months of birth; characterized by megalencephaly, optic atrophy, blindness, psychomotor regression, hypotonia, and spasticity; there is increased urinary excretion of N-acetylaspartic acid. MRI shows enlarged brain, decreased attenuation of cerebral and cerebellar white matter, and normal ventricles; pathologically, there is increased brain volume and weight and spongy degeneration in the subcortical white matter. Autosomal recessive inheritance, caused by mutation in the aspartoacyclase A gene (ASPA) on chromosome 17p in Jewish and non-Jewish affected individuals. SEE ALSO: leukodystrophy. SYN: Canavan sclerosis, Canavan-van Bogaert-Bertrand d., spongy degeneration of infancy.
Canavan-van Bogaert-Bertrand d. SYN: Canavan d..
Caroli d. [MIM*263200] congenital cystic dilation of the intrahepatic bile ducts, sometimes associated with intrahepatic stones and biliary obstruction; may be a part of the phenotype of infantile polycystic kidney d..
Carrington d. SYN: chronic eosinophilic pneumonia.
Carrión d. SYN: Oroya fever.
Castleman d. SYN: benign giant lymph node hyperplasia.
cat-bite d. rat-bite fever, presumably spread from rats to cats and thus to humans. SYN: cat-bite fever.
catscratch d. (CSD) an infection that causes chronic benign adenopathy in most cases, especially in children and young adults, usually associated with a cat scratch or bite. In most cases it is caused by the bacterium Bartonella henselae. The lymphadenopathy usually resolves spontaneously within a period of several months. The infection may cause other clinical symptoms such as fever of unknown origin, encephalitis, microabscess in the liver and spleen, and osteomyelitis. SYN: benign inoculation lymphoreticulosis, benign inoculation reticulosis, catscratch fever, regional granulomatous lymphadenitis.A primary lesion (typically a solitary papule 2–5 mm in diameter) develops at the site of inoculation in 50–95% of cases, usually within 1–2 weeks of inoculation. Regional lymphadenopathy commonly follows, in 75% of patients involving only a single lymph node. The node is usually tender and approximately 10% suppurate. Histopathologic study of an infected node shows lymphoid hyperplasia and granuloma formation with central areas of stellate necrosis containing neutrophils. About one-third of patients experience transitory systemic symptoms such as fever, headache, malaise, or rash. Spontaneous resolution of lymphadenopathy generally occurs in 6–12 weeks. Recovery from CSD confers immunity to further attacks. The Centers for D. Control estimates the incidence of CSD in the U.S. at 2.5 cases per 100,000 population per year. Most patients are under 21 years of age, and males are affected more often than females. In 1988, a bacterium named Afipia felis was cultured from the lymph nodes of patients with CSD, and for a time was believed to be the cause of the d.. More recently, serologic studies have shown that Bartonella hensalae, a Gram-negative bacterium, is probably the cause of most typical cases of CSD. The organism can sometimes be visualized with Warthin-Starry silver stain in infected lymph nodes. A serum immunofluorescent antibody test is available. Cats are the principal reservoir for Bartonella henselae; 25–40% of clinically healthy cats in the U.S. have antibody to the organism. Fleas have been shown to transmit infection from one cat to another. The majority of infected cats do not become ill. Although CSD is generally benign and self-limited, infection with Bartonella henselae is occasionally associated with severe or systemic involvement, including Parinaud's oculoglandular syndrome (granulomatous conjunctivitis with preauricular lymphadenitis), encephalopathy, myelitis, osteolytic lesions, erythema nodosum, etythema marginatum, thrombocytopenic purpura, nonimmune hemolytic anemia, arthritis, and pneumonia. In immunocompromised persons, particularly those with AIDS, infection with Bartonella henselae (perhaps not always associated with cats) takes the form of bacillary angiomatosis (BA), in which nodular tumors made up of densely proliferating blood vessels appear in the skin, bone, brain, liver, spleen, and other tissues. Antibiotic treatment is not recommended in uncomplicated catscratch d.. Doxycycline, ciprofloxacin, and gentamicin may be used in encephalitis or disseminated d.. Whereas these agents consistently lead to rapid improvement in bacillary angiomatosis, the response of glandular inflammation and other symptoms of catscratch d. is unpredictable.
celiac d. a d. occurring in children and adults characterized by sensitivity to gluten, with chronic inflammation and atrophy of the mucosa of the upper small intestine; manifestations include diarrhea, malabsorption, steatorrhea, and nutritional and vitamin deficiencies. SYN: celiac sprue, celiac syndrome, gluten enteropathy.
cement d. the osteolysis that frequently occurs in association with loosening of cemented total hip replacements; the microscopic particles of polymethylmethacrylate cement induce a biologic reaction by osteoclasts leading to bone resorption and progressive bone loss.
central core d. [MIM*117000] a congenital myopathy characterized by hypotonia, delay of motor development in infancy, and nonprogressive or slowly progressive muscle weakness; on biopsy the central core of muscle fibers stains abnormally, myofibrils are abnormally compact, and there is virtual absence of mitochondria and sarcoplasmic reticulum; histochemically, the cores are devoid of oxidative enzyme, phosphorylase, and ATPase activity; autosomal dominant inheritance, often subclinical, caused by mutation in the ryanodine receptor-1 gene (RYR1) on 19q.
cerebrovascular d. general term for a brain dysfunction caused by an abnormality of the cerebral blood supply.
Chagas d. SYN: South American trypanosomiasis.
Chagas-Cruz d. SYN: South American trypanosomiasis.
α chain d. a vague or indefinite term; could be used for α-heavy-chain d. (a lymphoplasma cell proliferative d. usually seen in Mediterranean men, characterized by intestinal involvement with steatorrhea, often progressive with fatal outcome) or α thalassemia (a genetic abnormality in the alpha globin chain of hemoglobin).
Charcot d. SYN: amyotrophic lateral sclerosis.
Charcot-Marie-Tooth d. SYN: peroneal muscular atrophy.
Cheadle d. SYN: infantile scurvy.
Chédiak-Higashi d. SYN: Chédiak-Higashi syndrome.
Chiari d. SYN: Chiari syndrome.
Chicago d. obsolete term for North American blastomycosis.
cholesterol ester storage d. [MIM*278000] a lipidosis caused by a deficiency of lysosomal acid lipase activity resulting in widespread accumulation of cholesterol esters and triglycerides in viscera with xanthomatosis, adrenal calcification, hepatosplenomegaly, foam cells in bone marrow and other tissues, and vacuolated lymphocytes in peripheral blood; autosomal recessive inheritance, caused by mutation in the lysosomal acid lipase gene (LIPA) on chromosome 10q. SYN: cholesteryl ester storage d., Wolman d., Wolman xanthomatosis.
cholesteryl ester storage d. SYN: cholesterol ester storage d..
Christensen-Krabbe d. SYN: poliodystrophia cerebri progressiva infantilis.
Christian d. 1. SYN: Hand-Schüller-Christian d.. 2. SYN: relapsing febrile nodular nonsuppurative panniculitis.
Christmas d. SYN: hemophilia B.
chronic active liver d. SYN: chronic hepatitis.
chronic granulomatous d. a congenital defect in the killing of phagocytosed bacteria by polymorphonuclear leukocytes, which cannot increase their oxygen metabolism either because of defective cytochrome [MIM*233710 and MIM*233690] or other specific factor deficiencies [MIM*233700 and MIM*306400]. As a result there is an increased susceptibility to severe infection by catalase-positive microorganisms; inheritance is usually autosomal recessive or X-linked. SYN: congenital dysphagocytosis, granulomatous d..
chronic hypertensive d. the chronic accumulative effects of long-standing high blood pressure on such vital organs as the heart, kidney, and brain.
chronic obstructive pulmonary d. (COPD) general term used for those diseases with permanent or temporary narrowing of small bronchi, in which forced expiratory flow is slowed, especially when no etiologic or other more specific term can be applied.
chylomicron retention d. an inherited disorder in which apolipoprotein B-48 is retained in intestine and absent in plasma; results in fat malabsorption.
Coats d. SYN: exudative retinitis.
Cockayne d. SYN: Cockayne syndrome.
cold hemagglutinin d. a condition associated with the presence of hemagglutinating autoantibody active in vivo but in vitro particularly or solely active in the cold; when the concentration of IgM antibody is high there may be increased serum viscosity, but clinical manifestations (due to hemagglutination) usually appear following exposure to cold; hemolysis usually is mild but may be severe, resulting in autoimmune hemolytic anemia, cold antibody type. SYN: cold agglutinin syndrome.
collagen d., collagen-vascular d. a group of generalized diseases affecting connective tissue and frequently characterized by fibrinoid necrosis or vasculitis; in some collagen diseases, auto-immunization, particularly antinuclear antibodies, has been shown and circulating immune complexes are found. The term is not entirely acceptable because there is no evidence that collagen is primarily involved; “collagen” was once synonymous with “connective tissue” rather than describing a specific fibrinous protein in that tissue. SEE ALSO: connective-tissue d..
combined system d. SYN: subacute combined degeneration of the spinal cord.
communicable d. any d. that is transmissible by infection or contagion directly or through the agency of a vector.
Concato d. SYN: polyserositis.
connective-tissue d. a group of generalized diseases affecting connective tissue, especially those not inherited as mendelian characteristics; rheumatic fever and rheumatoid arthritis were first proposed as such diseases, and other so-called collagen diseases have been added.
Conradi d. [MIM*215100 & MIM*302950] SYN: chondrodysplasia calcificans congenita.
Conradi-Hünermann d. SYN: chondrodysplasia calcificans congenita.
contagious d. an infectious d. transmissible by direct or indirect contact; now used synonymously with communicable d..
Cori d. SYN: type 3 glycogenosis.
Corrigan d. SYN: aortic regurgitation.
Cowden d. [MIM*158350] hypertrichosis and gingival fibromatosis from infancy, accompanied by postpubertal fibroadenomatous breast enlargement; papules of the face are characteristic of multiple trichilemmomas. SYN: multiple hamartoma syndrome.
Creutzfeldt-Jakob d. (CJD) a progressive neurologic disorder, one of the subacute spongiform encephalopathies caused by prions. Clinical features of CJD include a progressive cerebellar syndrome, including ataxia, abnormalities of gait and speech, and dementia. In most patients, these symptoms are followed by involuntary movements (myoclonus) and the appearance of a typical diagnostic electroencephalogram tracing (burst suppression, consisting of intermittent sharp and slow wave complexes on a flat background). The average survival is less than 1 year after onset of symptoms. Changes in the CSF are absent or nonspecific. Mild cortical atrophy and ventricular dilation may be grossly evident. On microscopic examination the distinctive finding is spongiform encephalopathy in gray matter throughout the brain and spinal cord. Severe neuronal loss and gliosis are also present and mild demyelination may occur. Ultrastructural changes include formation of intracytoplasmic vacuoles, the basis for the spongy appearance. CJD occurs worldwide at a rate of about 1–2 cases per million population per year; most cases are sporadic, but 10–12% are inherited. The peak incidence is between 55 and 65 years of age; the d. is rare before age 30. Cases of iatrogenic Creutzfeldt-Jakob d. have been associated with corneal transplants, electrode implants, dura mater grafts, and administration of human growth hormone. CJD is caused by a prion protein (an abnormal isoform of amyloid protein) that serves as a nucleating factor, inducing abnormalities in other proteins. This protein is detectable by Western blot early in the course of clinical d.. Prion diseases besides CJD include Gerstmann-Sträussler-Scheinker syndrome, fatal familial insomnia, and kuru in humans; scrapie in sheep and goats; bovine spongiform encephalopathy (mad cow d.) in cattle; and similar encephalopathies and wasting syndromes in other species. All these diseases have been shown to be transmissible in laboratory animals. SEE ALSO: bovine spongiform encephalopathy.An unusual number of cases of Creutzfeldt-Jakob d. were reported in young persons in Great Britain during the 1990s. These patients displayed ataxia, memory impairment, dementia, and myoclonus. Besides the characteristic spongiform changes of CJD, autopsy specimens from these patients showed unusual amyloid plaques with dense eosinophilic centers extensively distributed throughout the cerebrum and cerebellum. These plaques, visible with routine staining methods, had not previously been noted in Creutzfeldt-Jakob d., but did resemble plaques seen in kuru. In addition, these patients did not display the EEG changes characteristic of classical CJD. An association is suspected between this regional cluster of variant Creutzfeldt-Jakob d. and an epizootic of bovine spongiform encephalopathy that affected more than 150,000 cattle in Britain between 1986 and 1996. However, review of mortality statistics shows no increase in deaths due to CJD among butchers, farmers, and veterinarians in England and Wales between 1979 and 1996. See Also bovine spongiform encephalopathy.
Crigler-Najjar d. SYN: Crigler-Najjar syndrome.
Crocq d. SYN: acrocyanosis.
Crohn d. SYN: regional enteritis.
Crouzon d. SYN: Crouzon syndrome.
Cruveilhier-Baumgarten d. SYN: Cruveilhier-Baumgarten syndrome.
Cushing d. adrenal hyperplasia (Cushing syndrome) caused by an ACTH-secreting basophil adenoma of the pituitary. SYN: Cushing pituitary basophilism.
Cushing d. of the omentum central obesity in association with glucocorticoid excess, in which adipose stromal cells of the omental fat, but not subcutaneous tissue; can generate active cortisol from inactive cortisone. Patients have increased cortisol production and urinary cortisol excretion but no abnormality in the hypothalamico-pituitary-adrenal axis.
cystic d. of the breast fibrocystic condition of the breasts.
cysticercus d. SYN: cysticercosis.
cystic d. of renal medulla [MIM*256100] presence of small cysts in the renal medulla associated with anemia, sodium depletion, and chronic renal failure. It is of two types: 1) fatal autosomal recessive or juvenile type (also called familial juvenile nephrophthisis), beginning at about age 10 with an average duration of 6–8 years; 2) autosomal dominant or adult type. SYN: microcystic d. of renal medulla.
cystine storage d. SYN: cystinosis.
cytomegalic inclusion d. caused by Cytomegalovirus, a member of the Herpesviridae family; the presence of inclusion bodies within the cytoplasm and nuclei of enlarged cells of various organs of newborn infants dying with jaundice, hepatomegaly, splenomegaly, purpura, thrombocytopenia, and fever; the condition also occurs, at all ages, as a complication of other diseases in which immune mechanisms are severely depressed, and has been found incidentally in salivary gland epithelium, apparently as a localized or mild infection (salivary gland virus d.). SYN: cytomegalovirus d., inclusion body d..
cytomegalovirus d. SYN: cytomegalic inclusion d..
Daae d. SYN: epidemic pleurodynia.
Danielssen d. SYN: anesthetic leprosy.
Danielssen-Boeck d. SYN: anesthetic leprosy.
Darier d. SYN: keratosis follicularis.
Darling d. SYN: histoplasmosis.
Davies d. SYN: endomyocardial fibrosis.
decompression d. SYN: decompression sickness.
deer-fly d. SYN: tularemia.
deficiency d. any d. resulting from undernutrition or an inadequacy of calories, proteins, essential amino acids, fatty acids, vitamins, or trace minerals.
degenerative joint d. SYN: osteoarthritis.
Degos d. SYN: malignant atrophic papulosis.
Dejerine d. SYN: Dejerine-Sottas d..
Dejerine-Sottas d. a familial type of demyelinating sensorimotor polyneuropathy that begins in early childhood and is slowly progressive; clinically characterized by foot pain and paresthesias, followed by symmetrical weakness and wasting of the distal limbs; one of the causes of stork legs; patients are wheelchair-bound at an early age; peripheral nerves are palpably enlarged and non-tender; pathologically, onion bulb formation is seen in the nerves: whorls of overlapping, intertwined Schwann cell processes that encircle bare axons; usually autosomal recessive inheritance; an autosomal dominant form also exists; both forms can be caused by mutations in the peripheral myelin protein gene 22 (PMP22) on 17q or in the myelin protein zero gene (MPZ) on 1q. SYN: Dejerine d., hereditary hypertrophic neuropathy, progressive hypertrophic polyneuropathy.
demyelinating d. generic term for a group of diseases, of unknown cause, in which there is extensive loss of the myelin in the central nervous system, as in multiple sclerosis and Schilder d..
dense-deposit d. See membranoproliferative glomerulonephritis.
de Quervain d. fibrosis of the sheath of a tendon of the thumb. SYN: radial styloid tendovaginitis.
Dercum d. SYN: adiposis dolorosa.
Deutschländer d. tumor of one of the metatarsal bones;
Devic d. SYN: neuromyelitis optica.
diffuse Lewy body d. a degenerative cerebral disorder of the elderly, characterized initially by progressive dementia or psychosis, and subsequently by parkinsonian findings, usually with severe rigidity; other manifestations include involuntary movements, myoclonus, dysphagia, and orthostatic hypotension. Pathologically, Lewy bodies are present diffusely in the nuclei of the hypothalamus, basal forebrain, and brainstem. SYN: Lewy body dementia.
Di Guglielmo d. the acute form of erythremic myelosis. SYN: Di Guglielmo syndrome.
disappearing bone d. extensive decalcification of a single bone; of unknown cause, sometimes associated with angioma. SYN: Gorham d., Gorham syndrome.
diverticular d. symptomatic congenital or acquired diverticula of any portion of the gastrointestinal tract. Such diverticula occur in about 15% of the population but rarely cause symptoms.
dog d. SYN: phlebotomus fever.
dominantly inherited Lévi d. SYN: snub-nose dwarfism.
Donohue d. SYN: leprechaunism.
drug-induced d. a toxic reaction to or morbid condition resulting from the administration of a drug.
Dubois d. SYN: Dubois abscesses, under abscess.
Duchenne d. SYN: Duchenne dystrophy.
Duchenne-Aran d. SYN: amyotrophic lateral sclerosis.
Duhring d. SYN: dermatitis herpetiformis.
Dukes d. SYN: exanthema subitum.
Duncan d. [MIM*308240] SYN: X-linked lymphoproliferative syndrome. SYN: lymphoproliferative syndrome.
Dupuytren d. of the foot SYN: plantar fibromatosis.
Duroziez d. congenital stenosis of the mitral valve.
Dutton d. african tick-borne relapsing fever caused by Borrelia duttonii and spread by the soft tick, Ornithodoros moubata. SYN: Dutton relapsing fever.
Eales d. peripheral retinal periphlebitis causing recurrent retinal or intravitreous hemorrhages in young adults.
Ebstein d. SYN: Ebstein anomaly.
echinococcus d. SYN: echinococcosis.
Eisenmenger d. SYN: Eisenmenger complex.
elephant man's d. 1. SYN: Proteus syndrome. 2. SYN: neurofibromatosis.
elevator d. respiratory distress arising in persons who work in grain elevators resulting from inhalation of dusts or insects.
emotional d. mental illness.
endemic d. continued prevalence of a d. in a specific population or area. SEE ALSO: endemic, enzootic.
Engelmann d. SYN: diaphysial dysplasia.
English sweating d. a d. of unknown nature that appeared in England and spread over Europe in 1485, 1508 and 1528–30 and was characterized by heavy sweats, prostration, and a high fatality rate. SYN: sudor anglicus.
eosinophilic endomyocardial d. a restrictive cardiomyopathy associated with hyperproduction of eosinophiles and their cardiac infiltration, clinically characterized by diastolic and later systolic ventricular failure. Sometimes associated with Churg-Strauss syndrome or eosinophilic pericarditis.
epidemic d. marked increase in prevalence of a d. in a specific population or area, usually with an environmental cause, such as an infectious or toxic agent.
Epstein d. SYN: diphtheroid (1) .
Erb d. SYN: progressive bulbar paralysis.
Erb-Charcot d. 1. SYN: spastic diplegia. 2. SYN: spastic paraplegia.
Erdheim d. SYN: cystic medial necrosis.
ergot alkaloid-associated heart d. heart d. caused by endomyocardial fibrosis which extends into valve structures, producing stenosis and/or regurgitation, associated with ergot alkaloid use.
Eulenburg d. SYN: congenital paramyotonia.
exanthematous d. exanthema.
extramammary Paget d. an intraepidermal form of mucinous adenocarcinoma, most commonly in the anogenital region, presenting as erythematous plaques in the elderly, which may be associated with sweat gland or regional visceral carcinoma. SYN: Paget d. (3) .
extrapyramidal d. a general term for a number of disorders caused by abnormalities of the basal ganglia or certain brainstem or thalamic nuclei; characterized by motor deficits, loss of postural reflexes, bradykinesia, tremor, rigidity, and various involuntary movements. SYN: extrapyramidal motor system d..
extrapyramidal motor system d. SYN: extrapyramidal d..
Fabry d. [MIM*301500] due to deficiency of α-galactosidase and characterized by abnormal accumulations of neutral glycolipids ( e.g., globotriaosylceramide) in endothelial cells in blood vessel walls; clinical findings include angiokeratomas on the thighs, buttocks, and genitalia, hypohidrosis, paresthesia in extremities, cornea verticillata, and spokelike posterior subcapsular cataracts; death results from renal, cardiac, or cerebrovascular complications; X-linked recessive inheritance caused by mutation the α-galactosidase gene (GLA) on Xq. SYN: diffuse angiokeratoma, glycolipid lipidosis.
Fahr d. progressive calcific deposition in the walls of blood vessels of the basal ganglia, in young to middle-aged persons; occasionally associated with mental retardation and extrapyramidal symptoms.
Farber d. SYN: disseminated lipogranulomatosis.
Favre-Durand-Nicholas d. SYN: venereal lymphogranuloma.
Favre-Racouchot d. comedones developing on sun-damaged skin due to obstruction of pilosebaceous follicles by solar elastosis. SYN: Favre-Racouchot syndrome, solar comedo.
Fazio-Londe d. [MIM*211500] a progressive bulbar palsy affecting the brainstem; due to motor neuron degeneration; a variant of spinal muscular atrophy (q.v.).
Feer d. SYN: acrodynia (2) .
femoropopliteal occlusive d. obstruction of the femoral and popliteal arteries by atherosclerosis.
fibrocystic d. of the pancreas SYN: cystic fibrosis.
fifth d. SYN: erythema infectiosum. [after scarlatina, morbilli, rubella, and fourth d.]
Filatov d. SYN: Filatov-Dukes d..
Filatov-Dukes d. an exanthem-producing infectious d. of childhood of unknown etiology. SYN: Filatov d., parascarlatina, scarlatinella, scarlatinoid (2) .
fish eye d. an inherited disorder resulting in low HDL cholesterol and corneal opacities; also, low LCAT activity.
flax-dresser's d. chronic obstructive pulmonary d. caused by inhalation of particles of unprocessed flax; a form of byssinosis. SEE ALSO: byssinosis.
Flegel d. SYN: hyperkeratosis lenticularis perstans.
flint d. SYN: chalicosis.
focal metastatic d. presence of a single area of metastasis of a malignant tumor or infection distant from the primary lesion.
Folling d. SYN: phenylketonuria.
foot-and-mouth d. (FMD) a highly infectious d. of wide distribution and great economic importance, occurring in cattle, swine, sheep, goats and all wild and domestic cloven-footed animals caused by a picornavirus (genus Aphthovirus) and characterized by vesicular eruptions in the mouth, tongue, hoofs, and udder; humans are rarely affected. SYN: aftosa.
Forbes d. SYN: type 3 glycogenosis.
Fordyce d. SYN: Fordyce spots, under spot.
Forestier d. SYN: diffuse idiopathic skeletal hyperostosis.
Fothergill d. 1. SYN: trigeminal neuralgia. 2. SYN: anginose scarlatina.
Fournier d. infective gangrene involving the scrotum. SYN: Fournier gangrene, syphiloma of Fournier.
fourth d. SYN: exanthema subitum.
Fox-Fordyce d. a chronic pruritic eruption of dry papules and distended ruptured apocrine glands, seen mostly in women, with follicular hyperkeratosis of the nipples, axillae, and pubic and sternal regions. SYN: apocrine miliaria.
Franklin d. SYN: γ-heavy-chain d..
Freiberg d. osteonecrosis of second metatarsal head. SYN: Freiberg infarction.
Friend d. mouse leukemia caused by the Friend leukemia virus, a member of the family Retroviridae.
functional d. SYN: functional disorder.
functional cardiovascular d. a euphemism for cardiovascular symptoms deemed to be psychogenic. More generally, sometimes used for abnormal cardiac function.
fusospirochetal d. infection of the mouth and/or pharynx associated with fusiform bacilli and spirochetes, commonly part of the normal flora of the mouth. SEE ALSO: necrotizing ulcerative gingivitis.
Gairdner d. attacks of cardiac distress accompanied by apprehension. SYN: angina pectoris sine dolore, angor pectoris (1) .
Gamna d. a form of chronic splenomegaly characterized by conspicuous thickening of the capsule and the presence of multiple, small, rustlike, brown foci (Gamna-Gandy bodies), which contain iron; this condition may be observed in fibrocongestive splenomegaly, sickle cell d., and some examples of hemochromatosis.
Gandy-Nanta d. siderotic splenomegaly, probably the same as Gamna d..
garapata d. tick fever occurring in Spain.
Garré d. SYN: sclerosing osteitis.
gastroesophageal reflux d. (GERD) a syndrome due to structural or functional incompetence of the lower esophageal sphincter, which permits retrograde flow of acidic gastric juice into the esophagus.Although the underlying abnormality in GERD is apparently inborn and irreversible, the incidence increases with age. In addition to reflux, most cases involve disordered gastric motility and prolonged gastric emptying time. Symptoms include recurring epigastric and retrosternal distress, usually described as heartburn, along with varying degrees of belching, nausea, gagging, cough, or hoarseness. GERD is increasingly recognized as a cause of throat irritation and chronic cough. The incidence of GERD among adults with asthma may be as high as 80%. The disorder is more common in men. The likelihood of symptomatic reflux is increased by obesity, pregnancy, cigarette smoking, diabetes mellitus, scleroderma, and other connective tissue diseases. Symptoms can be induced by recumbency, strenuous exercise, heavy lifting, smoking, eating large meals, or consuming alcohol, chocolate, fatty foods, and drugs such as theophylline, calcium channel blockers, and anticholinergic agents. Acid reflux can cause peptic esophagitis, ulcer formation, or esophageal stricture. Metaplastic changes in esophageal squamous epithelium, called Barrett's esophagus, can progress to carcinoma. Diagnosis is by history, esophageal pH monitoring, radiologic study showing reflux of swallowed barium, and endoscopy to identify ulceration or stricture and permit biopsy to rule out malignancy. Treatment includes avoidance of known causes and administration of antacids, H₂ antagonists, prokinetic agents, and proton pump inhibitors.
Gaucher d. a lysosomal storage disorder due to a deficiency of glucocerebrosidase resulting in accumulation of glucocerebroside; high incidence among persons of Ashkenazi Jewish descent; occurs most severely in infants, characterized by hepatosplenomegaly, hematologic abnormalities, bone lesions, neurological manifestations with ataxia, spastic paraplegia, seizures, and dementia, and presence of characteristic histiocytes (Gaucher cells) in the viscera; autosomal recessive inheritance, caused by mutation in the glucocerebrosidase A gene (GBA) on chromosome 1q. There are three main forms: type I, noncerebral juvenile [MIM*230800]; type II, cerebral juvenile [MIM*230900]; and type III, adult cerebral [MIM*231000]; the juvenile forms are most severe. SYN: cerebroside lipidosis.
Gerhardt-Mitchell d. SYN: erythromelalgia.
Gerlier d. SYN: vestibular neuronitis.
gestational trophoblastic d. SYN: hydatidiform mole.
Gierke d. SYN: type 1 glycogenosis.
Gilbert d. SYN: familial nonhemolytic jaundice.
Gilchrist d. SYN: blastomycosis.
Gilles de la Tourette d. SYN: Tourette syndrome.
Glanzmann d. SYN: Glanzmann thrombasthenia.
glycogen-storage d. SYN: glycogenosis.
Goldflam d. SYN: myasthenia gravis.
Gorham d. SYN: disappearing bone d..
Gougerot and Blum d. SYN: pigmented purpuric lichenoid dermatosis.
Gougerot-Sjögren d. SYN: Sjögren syndrome. [Sjögren, Henrik S.C.]
Gowers d. 1. SYN: saltatory spasm. 2. a distal type of progressive muscular dystrophy.
graft versus host d. an incompatibility reaction (that may be fatal) in a subject (host) of low immunologic competence who has been the recipient of immunologically competent lymphoid tissue from a donor who is immunologically different from the recipient; the reaction, or d., is the result of action of the transplanted cells against those host tissues that possess an antigen not found in the donor. Seen most commonly following bone marrow transplantation, acute d. is seen after 7–30 days and chronic d. weeks to months after transplantation, affecting, principally, the gastrointestinal tract, liver, and skin. SYN: GVH d..
granulomatous d. SYN: chronic granulomatous d..
Graves d. 1. toxic goiter characterized by diffuse hyperplasia of the thyroid gland, a form of hyperthyroidism; exophthalmos is a common, but not invariable, concomitant; 2. thyroid dysfunction and all or any of its clinical associations; 3. an organ-specific autoimmune d. of the thyroid gland. See thyrotoxicosis, Hashimoto thyroiditis, goiter, myxedema. SYN: Basedow d., ophthalmic hyperthyroidism, Parry d..
Griesinger d. bilious typhoid of Griesinger, a severe form of louse-borne relapsing fever caused by Borrelia recurrentis and causing high fever, epistaxis, dyspnea, intense jaundice, purpura, and splenomegaly.
Grover d. SYN: transient acantholytic dermatosis.
GVH d. SYN: graft versus host d..
Haff d. rhabdomyolysis resultant from an unidentified toxin contained in some fishes, including turbot and biffalo fish. [Haff, an arm of the Baltic Sea in East Prussia]
Haglund d. an abnormal prominence of the posterior superior lateral aspect of the os calcis. SYN: Haglund deformity.
Hailey-Hailey d. SYN: benign familial chronic pemphigus.
Hallervorden-Spatz d. SYN: Hallervorden-Spatz syndrome.
Hallopeau d. SYN: pemphigus vegetans (2) .
Hamman d. SYN: Hamman syndrome.
Hammond d. SYN: athetosis.
hand-foot-and-mouth d. an exanthematous eruption in small children usually consisting of small, pearl-gray vesicles of the fingers, toes, palms, and soles, accompanied by often painful vesicles and ulceration of the buccal mucous membrane and the tongue and by slight fever; the d. lasts 4–7 days, and is usually caused by coxsackie virus type A-16, but other types have been identified.
Hand-Schüller-Christian d. the chronic disseminated form of Langerhans cell histiocytosis. The classic triad of signs consists of diabetes insipidus, exophthalmos, and bony lesions composed of histiocytes. SYN: Christian d. (1) , Christian syndrome, normal cholesteremic xanthomatosis, Schüller d., Schüller syndrome.
Hansen d. SYN: leprosy.
Harada d. SYN: Harada syndrome.
Hartnup d. [MIM*234500] an autosomal recessively inherited metabolic disorder characterized by aminoaciduria which is due to defective renal tubular transport of neutral α-amino acids; there is increased urinary excretion of tryptophan derivatives caused by defective intestinal absorption and bacterial degradation of unabsorbed tryptophan in the gut; manifestations include pellagralike, light-sensitive skin rash with temporary cerebellar ataxia. SYN: Hartnup syndrome.
Hashimoto d. SYN: Hashimoto thyroiditis.
heavy chain d. a term used for a group of diseases, the paraproteinemias, characterized by production of homogeneous immunoglobulins or fragments, and associated with malignant disorders of the plasmacytic and lymphoid cell series. Three types have been recognized: γ-heavy-chain d., α-heavy-chain d., and μ-heavy-chain d.; each is diagnosed by the finding of the appropriate heavy-chain fragment in the serum, urine, or both.
α-heavy-chain d. the most common form of heavy-chain d., characterized by a finding in the serum of a protein reactive with antisera to α-chains but not light chains; clinical features include diarrhea, steatorrhea, and severe malabsorption.
γ-heavy-chain d. heavy-chain d. characterized by a finding in the serum and urine of a broad protein peak that is reactive with antisera to γ-chains and unreactive with antisera to light chains; common features include anemia, lymphocytosis, eosinophilia, thrombocytopenia, hyperuricemia, lymphadenopathy, and hepatosplenomegaly. SYN: Franklin d..
μ-heavy-chain d. the rarest form of heavy-chain d., primarily seen in patients with long-standing chronic lymphatic leukemia; diagnosis is made on immunoelectrophoresis by finding a component reactive with antisera to μ-chains but not to light chains.
Heck d. SYN: focal epithelial hyperplasia.
Heerfordt d. SYN: uveoparotid fever.
hemoglobin C d. the homozygous state of hemoglobin C.
hemoglobin H d. hemoglobin H.
hemolytic d. of newborn SYN: erythroblastosis fetalis.
hemorrhagic d. of the newborn a syndrome characterized by spontaneous internal or external bleeding accompanied by hypoprothrombinemia, slightly decreased platelets, and markedly elevated bleeding and clotting times, usually occurring between the third and sixth days of life and effectively treated with vitamin K.
herring-worm d. SYN: anisakiasis.
Hers d. SYN: type 6 glycogenosis.
Hirschsprung d. SYN: congenital megacolon.
Hodgkin d. a d. marked by chronic enlargement of the lymph nodes, often local at the onset and later generalized, together with enlargement of the spleen and often of the liver, no pronounced leukocytosis, and commonly anemia and continuous or remittent (Pel-Ebstein) fever; considered to be a malignant neoplasm of lymphoid cells of uncertain origin (Reed-Sternberg cells), associated with inflammatory infiltration of lymphocytes and eosinophilic leukocytes and fibrosis; can be classified into lymphocytic predominant, nodular sclerosing, mixed cellularity, and lymphocytic depletion type; a similar d. occurs in domestic cats. SYN: Hodgkin lymphoma, lymphadenoma (2) .
Hodgson d. dilation of the arch of the aorta associated with insufficiency of the aortic valve.
holoendemic d. (hol′o-en-dem′ik) a d. for which a high prevalent level of infection begins early in life and affects most or all of the child population, leading to a state of equilibrium, such that the adult population shows evidence of the d. much less frequently than do the children.
hookworm d. See ancylostomiasis, necatoriasis.
Huntington d. [MIM*143100] SYN: Huntington chorea.
Hurler d. SYN: Hurler syndrome.
Hurst d. SYN: acute necrotizing hemorrhagic encephalomyelitis.
Hutchinson-Gilford d. SYN: progeria.
hyaline membrane d. of the newborn a d. seen especially in premature neonates with respiratory distress; characterized postmortem by atelectasis and alveolar ducts lined by an eosinophilic membrane; also associated with reduced amounts of lung surfactant. SYN: hyaline membrane syndrome, respiratory distress syndrome of the newborn.
hydatid d. infection of humans, sheep, and most other herbivorous and omnivorous mammals with larvae of the tapeworm Echinococcus.
hyperendemic d. a d. that is constantly present at a high incidence and/or prevalence rate and affects all age groups equally.
Iceland d. SYN: epidemic neuromyasthenia.
I-cell d. SYN: mucolipidosis II.
idiopathic d. a d. of unknown cause or mechanism.
immune complex d. an immunologic category of diseases evoked by the deposition of antigen-antibody in the microvasculature. Complement is frequently involved and the breakdown products of complement attract polymorphonuclear leukocytes to the site of deposition. Damage to tissue is frequently caused by the process of “frustrated” phagocytosis by polymorphonuclear cells. Vasculitis or nephritis is common. Arthus phenomenon and serum sickness are classic examples, but many other disorders, including most of the connective tissue diseases, may belong in this immunologic category; immune complex diseases can also occur during a variety of diseases of known etiology, such as subacute bacterial endocarditis. SEE ALSO: autoimmune d.. SYN: immune complex disorder, type III hypersensitivity reaction.
immunoproliferative small intestinal d. diffuse lymphoplasmacytic infiltration of the proximal small bowel mucosa and mesenteric lymph nodes resulting in diarrhea, weight loss, abdominal pain, and clubbing of fingers and toes; seen in poor people in developing countries. SYN: Mediterranean lymphoma.
inborn lysosomal d. inherited disorder of one or more degradative enzymes normally located in lysosomes leading to accumulation (storage) of abnormal quantities of a substance, such as a glycosaminoglycan as in Hurler syndrome or a lipopolysaccharide as in Gaucher d..
inclusion body d. SYN: cytomegalic inclusion d..
inclusion cell d. SYN: mucolipidosis II.
industrial d. a morbid condition resulting from exposure to an agent discharged by a commercial enterprise into the environment. Cf.:occupational d..
infantile celiac d. gluten-sensitive enteropathy appearing in infancy, often before the age of 9 months and characterized by acute onset, diarrhea, abdominal pain, and “failure to thrive.”
infectious d., infective d. a d. resulting from the presence and activity of a microbial agent.
intercurrent d. a new d. occurring during the course of another d., not related to the primary d. process.
interstitial d. a d. occurring chiefly in the connective-tissue framework of an organ, the parenchyma suffering secondarily.
iron-storage d. the storage of excess iron in the parenchyma of many organs, as in idiopathic hemochromatosis or transfusion hemosiderosis.
island d. SYN: tsutsugamushi d..
Itai-Itai d. a form of cadmium poisoning described in Japanese people, characterized by renal tubular dysfunction, osteomalacia, pseudofractures, and anemia, caused by ingestion of contaminated shellfish or other sources containing cadmium.
Jaffe-Lichtenstein d. obsolete term for fibrous dysplasia of bone.
Jansky-Bielschowsky d. cerebral sphingolipidosis, early juvenile type.
Jensen d. SYN: retinochoroiditis juxtapapillaris.
jumping d., jumper d. one of the pathologic startle syndromes found in isolated parts of the world, characterized by greatly exaggerated responses, such as jumping, flinging the arms and yelling, to minimal stimuli. SYN: jumping Frenchmen of Maine d., jumper d. of Maine.
jumping Frenchmen of Maine d., jumper d. of Maine SYN: jumping d..
Jüngling d. SYN: osteitis tuberculosa multiplex cystica.
Kashin-Bek d. a form of generalized osteoarthrosis limited to areas of Asia, including the Urov river; believed to result from ingestion of wheat infected with the fungus Fusarium sporotrichiella.
Katayama d. acute early egg-laying phase of schistosomiasis, a toxemic syndrome in heavy primary infections, rarely seen in chronic cases. It is considered a form of immune complex d. or serum sickness–like condition. Described for schistosomiasis japonica, but observed with other forms as well. SYN: Katayama fever. [town in Japan where the d. is common]
Kawasaki d. a systemic vasculitis of unknown origin that occurs primarily in children under 8 years of age. Symptoms include a fever lasting more than 5 days, polymorphic rash, erythematous, dry, cracking lips; conjunctival injection, swelling of the hands and feet, irritability, adenopathy, and a perineal desquamative rash. Approximately 20% of untreated patients may develop coronary artery aneurysms. As the child recovers from the illness, thrombocytosis and peeling of the fingertips occurs. SYN: Kawasaki syndrome, mucocutaneous lymph node syndrome.
Kennedy d. an X-linked recessive disorder characterized by progressive spinal and bulbar muscular atrophy; associated features include distal degeneration of sensory axons, and signs of endocrine dysfunction, including diabetes mellitus, gynecomastia, and testicular atrophy. SYN: X-linked recessive bulbospinal neuronopathy.
Kienböck d. osteonecrosis of the lunate bone resulting from unknown etiolgy, although can occur after trauma. SYN: lunatomalacia.
Kikuchi d. necrotizing lymphadenitis of unknown etiology, most often encountered in young women in Japan but also in other parts of the world; lymph node enlargement, associated with fever, subsides spontaneously.
Kimmelstiel-Wilson d. SYN: Kimmelstiel-Wilson syndrome.
Kimura d. SYN: angiolymphoid hyperplasia with eosinophilia.
kinky-hair d., kinky hair d. [MIM*309400] an inborn error of copper metabolism with onset within a few weeks of birth; manifested by short, sparse, poorly pigmented kinky hair; failure to thrive; development of seizures; spasticity; and progressive mental deterioration leading to death. X-linked recessive inheritance due to a defect of copper transport, caused by mutation in the Menkes gene (MNK), which encodes a copper-transporting ATPase on Xq. SYN: Menkes syndrome, trichopoliodystrophy.
Köhler d. osteonecrosis of the tarsal navicular bone or of the patella.
kok d. SYN: hyperekplexia.
Krabbe d. SYN: globoid cell leukodystrophy.
Kufs d. cerebral sphingolipidosis, adult type.
Kugelberg-Welander d. SYN: spinal muscular atrophy, type III.
Kussmaul d. SYN: polyarteritis nodosa.
Kyasanur Forest d. a d. occurring among forest workers in the Kyasanur Forest and in Mysore, India, caused by a Flavivirus in the family Flaviviridae transmitted chiefly by Haemaphysalis spinigera, although other ticks have been implicated as well; symptoms include fever, headache, back and limb pains, diarrhea, and intestinal bleeding; central nervous system symptoms do not occur.
Kyrle d. SYN: hyperkeratosis follicularis et parafollicularis.
Lafora d. SYN: Lafora body d..
Lafora body d. [MIM*254780] a form of progressive myoclonus epilepsy beginning from age 6–19; characterized by generalized tonic-clonic seizures, resting and action myoclonus, ataxia, dementia, and classic EEG findings, including polyspike and wave discharges; basophilic cytoplasmic inclusion bodies present in portions of the brain, the liver, and skin, as well as the duct cells of the sweat glands. Death usually occurs within 10 years of onset; autosomal recessive inheritance, caused by mutation in the progressive myoclonic epilepsy 2 gene (EPM2A) on chromosome 6q. SYN: Lafora d..
Lane d. SYN: erythema palmare hereditarium.
L-chain d. SYN: Bence Jones myeloma.
Legg-Calvé-Perthes d., Legg-Perthes d., Legg d. epiphysial osteonecrosis of the upper end of the femur. SYN: Calvé-Perthes d., coxa plana, osteochondritis deformans juvenilis, Perthes d., pseudocoxalgia, quiet hip d..
Legionnaires d. an acute infectious d., caused by Legionella pneumophila, with prodromal influenzalike symptoms and a rapidly rising high fever, followed by severe pneumonia and production of usually nonpurulent sputum, and sometimes mental confusion, hepatic fatty changes, and renal tubular degeneration. It has a high case-fatality rate; acquired from contaminated water, usually by aerosolization rather than being transmitted from person-to-person. SYN: legionellosis. [American Legion convention, 1976, at which many delegates were so affected]
Leigh d. [MIM*256000] subacute encephalomyelopathy affecting infants, causing seizures, spasticity, optic atrophy, and dementia; the genetic causation is heterogeneous; may be associated with deficiency of cytochrome c oxidase or NADH-ubiquinone oxidoreductase or other enzymes involved in energy metabolism. Autosomal recessive, X-linked recessive and mitochondrial inheritance have been described; mutations have been identified in the surfeit-1 gene (SURF) [MIM*185620] on chromosome 9, in a mtDNA-encoded subunit of ATP synthase [MIM*516060], in the X-linked E1-alpha subunit of pyruvate dehydrogenase [MIM*312170], and in several subunits of mitochondrial complex I [MIM*161015 and MIM*620141]. SYN: necrotizing encephalomyelopathy, necrotizing encephalopathy.
Leiner d. SYN: erythroderma desquamativum.
Lenègre d. SYN: Lenègre syndrome.
lenticular progressive d. SYN: WILSON DISEASE51.
Leri-Weill d. SYN: dyschondrosteosis.
Letterer-Siwe d. the acute disseminated form of Langerhans cell histiocytosis. SYN: nonlipid histiocytosis.
Lev d. SYN: Lev syndrome.
Lindau d. SYN: von Hippel-Lindau syndrome.
linear IgA bullous d. in children SYN: chronic bullous dermatosis of childhood.
Little d. SYN: spastic diplegia.
Lobo d. SYN: lobomycosis.
Löffler d. SYN: Löffler endocarditis.
Lorain d. SYN: idiopathic infantilism.
Lou Gehrig d. SYN: amyotrophic lateral sclerosis.
Luft d. [MIM*238800] a metabolic d. due to relative uncoupling of phosphorylation in skeletal muscle causing myopathy and general hypermetabolism; a mitochondial myopathy.
lung fluke d. infection with the lung fluke, Clonorchis sinensis.
Lutz-Splendore-Almeida d. SYN: paracoccidioidomycosis.
Lyell d. SYN: staphylococcal scalded skin syndrome.
Lyme d. a subacute inflammatory disorder caused by infection with Borrelia burgdorferi, a nonpyogenic spirochete transmitted by Ixodes scapularis, the deer tick, in the eastern U.S. and I. pacificus, the western black-legged tick, in the western U.S.; the characteristic skin lesion, erythema chronicum migrans, is usually preceded or accompanied by fever, malaise, fatigue, headache, and stiff neck; neurologic, cardiac, or articular manifestations may occur weeks to months later. Tick nymphs are thought to be responsible for about 90% of transmission to human beings. Nymphs and larvae feed especially on the white-footed mouse, Peromyscus leucopus, while the preferred host of adults is the deer. Infected reservoir animals and ticks do not become ill. Residual articular or neurologic symptoms, which may persist for months or years after the initial infection, probably represent an immune response to the organism. Variations in clinical features or severity from one patient to another may be due to inborn variations in immune response, perhaps linked to the human lymphocytic antigen system. SYN: Lyme borreliosis. [Lyme, CT, where first observed] Because of media coverage, Lyme d. has a higher profile than its occurrence warrants. Fewer than 18,000 cases are confirmed annually in the U.S. It is generally a benign, self-limited d., even when untreated. Antibody studies in endemic areas suggest that as many as 50% of persons who contract the infection never show symptoms. The case fatality rate is virtually zero. The diagnosis is essentially clinical. Serologic tests for antibody to B. burgdorferi are notoriously poor in both sensitivity and specificity. In nonendemic areas, false-positive test results statistically outnumber true positives. IgM antibody appears and peaks relatively late, so that one-half of patients are seronegative during the first month following appearance of the rash. Antibiotic treatment administered early can alter or prevent the expected acute immune response. IgG antibody persists for months or years after infection and hence affords no help in diagnosing acute d.. Given the nonspecific and variable clinical picture and the unreliability of laboratory diagnostic measures, it is inevitable that many cases of Lyme d. are missed, and that, conversely, the diagnosis is often wrongly made. A study assessing the costs of misdiagnosis of Lyme d. found that 60% of patients referred to a Lyme d. clinic had never had the d. and another 19% had a history of infection but no current d.. The drug of choice is doxycycline administered orally for several weeks. Amoxicillin is the standard alternative for children and pregnant patients. Recovery does not confer immunity to future attacks; in fact, in highly endemic areas, the reinfection rate may be as high as 20%. Infectious d. authorities do not recommend antibiotic prophylaxis after a tick bite, even in highly endemic areas, nor do they countenance treatment of asymptomatic persons who have serologic evidence of past infection. A vaccine consisting of outer surface protein A (OspA) of B. burgdorferi synthesized by a nonvirulent strain of recombinant Escherichia coli was released in 1998. Antibody induced by the vaccine enters a feeding tick and binds any spirochetes present, preventing their mobilization. Three doses of the vaccine administered over a 12-month period confer about 80% protection against Lyme d.. The vaccine is not approved for persons under age 15 and is recommended only for those living or working in highly endemic areas.
lysosomal d. a d. due to inadequate functioning of a lysosomal enzyme; most such diseases are associated with a storage d..
Machado-Joseph d. [MIM*109150] a rare form of hereditary ataxia, characterized by onset in early adult life of progressive, spinocerebellar and extrapyramidal d. with external ophthalmoplegia, rigidity dystonia symptoms, and, often, peripheral amyotrophy; found predominantly in people of Azorean ancestry; autosomal dominant inheritance, caused by a trinucleotide repeat expansion mutation in the Machado-Joseph gene (MJD1) on 14q. SYN: Azorean d., Portuguese-Azorean d.. [Surnames of two families studied in major descriptions of the d..]
mad cow d. SYN: bovine spongiform encephalopathy.
Madelung d. SYN: multiple symmetric lipomatosis.
Manson d. SYN: schistosomiasis mansoni.
maple bark d. hypersensitivity pneumonitis caused by spores of Cryptostroma corticale growing under the bark of stacked maple logs.
maple syrup urine d. [MIM*248600] an inborn error of metabolism caused by defective oxidative decarboxylation of α-keto acids of leucine, isoleucine, and valine; these branched-chain amino acids are present in the blood and urine in high concentrations; manifestations of d. include feeding difficulties, physical and mental retardation, and a urine odor similar to that of maple syrup; neonatal death is common. Autosomal recessive inheritance, caused by mutation in the E1, E2 or E3 subunit of the branched-chain α-keto acid dehydrogenase gene (BCKDH) on 19q. There are various forms differentiated by the subunit of BCKDH mutated. SYN: branched chain ketoaciduria, branched chain ketonuria, ketoacidemia.
marble bone d. SYN: osteopetrosis.
Marburg d. infection with an unusual rhabdovirus composed of RNA and lipid, tentatively assigned to the family of Filoviridae. Virus is &dquor;pantropic&dquor; and affects most organ systems.The d. is characterized by a prominent rash and hemorrhages in many organs and is often fatal. First seen among laboratory workers in Marburg, Germany, exposed to African green monkeys. Some person-to-person spread has been observed. Attempts to isolate virus should be done only in high-security laboratories. SYN: Marburg virus d..
Marburg virus d. SYN: Marburg d..
Marchiafava-Bignami d. a disorder recognized primarily by its pathological features, consisting of demyelination of the corpus callosum and cortical laminar necrosis involving the frontal and temporal lobes. Occurs predominantly in chronic alcoholics, particularly wine drinkers.
Marfan d. SYN: Marfan syndrome.
margarine d. erythema multiforme caused by an emulsifying agent used in the manufacture of margarine.
Marie-Strümpell d. SYN: ankylosing spondylitis.
Marion d. a congenital obstruction of the posterior urethra.
Martin d. a periosteoarthritis of the foot from excessive walking.
McArdle d. SYN: type 5 glycogenosis.
McArdle-Schmid-Pearson d. SYN: type 5 glycogenosis.
mechanobullous d. SYN: epidermolysis bullosa. [G. mechane, machine, + bullous]
Meige d. [MIM*153200] autosomal dominant lymphedema with onset at about the age of puberty.
Ménétrier d. gastric mucosal hyperplasia, either mucoid or glandular; the latter type may be associated with the Zollinger-Ellison syndrome. SYN: giant hypertrophy of gastric mucosa, hypertrophic gastritis, Ménétrier syndrome.
Ménière d. an affection characterized clinically by vertigo, nausea, vomiting, tinnitus, and progressive hearing loss due to hydrops of the endolymphatic duct. SYN: endolymphatic hydrops, Ménière syndrome.
mental d. mental illness.
Merzbacher-Pelizaeus d. SYN: Pelizaeus-Merzbacher d..
metabolic d. generic term for d. caused by an abnormal metabolic process. It can be congenital, due to inherited enzyme abnormality, or acquired, due to d. of an endocrine organ or failure of function of a metabolic important organ such as the liver.
Meyenburg d. SYN: relapsing polychondritis.
Meyer-Betz d. SYN: myoglobinuria.
Mibelli d. SYN: porokeratosis.
microcystic d. of renal medulla SYN: cystic d. of renal medulla.
micrometastatic d. the condition of a patient who has had all clinically evident cancer removed, but who may be expected to have a recurrence from metastases that are too small to be apparent.
microvillus inclusion d. a condition that begins at birth with persistent watery diarrhea and life-threatening malabsorption associated with villus atrophy and crypt hypoplasia in the small bowel; electron microscopy reveals microvillus inclusions in enterocytes. SYN: congenital microvillus atrophy.
Mikulicz d. benign swelling of the lacrimal, and usually also of the salivary glands in consequence of an infiltration of and replacement of the normal gland structure by lymphoid tissue. SEE ALSO: Mikulicz syndrome, Sjögren syndrome.
Milroy d. [MIM*153100] the congenital type of autosomal dominant lymphedema.
Minamata d. a neurologic disorder caused by methyl mercury intoxication; first described in the inhabitants of Minamata Bay, Japan, resulting from their eating fish contaminated with mercury industrial waste. Characterized by peripheral sensory loss, tremors, dysarthria, ataxia, and both hearing and visual loss.
miner's d. 1. SYN: ancylostomiasis, miner's nystagmus.
minimal-change d. SYN: lipoid nephrosis.
mixed connective-tissue d. d. with overlapping features of various systemic connective-tissue diseases and with serum antibodies to nuclear ribonucleoprotein.
molecular d. a d. in which the manifestations are due to alterations in molecular structure and function.
Mondor d. thrombophlebitis of the thoracoepigastric vein of the breast and chest wall.
Monge d. SYN: chronic mountain sickness.
Morgagni d. SYN: Adams-Stokes syndrome.
Morquio d. SYN: Morquio syndrome.
Morquio-Ullrich d. SYN: Morquio syndrome.
Morvan d. SYN: syringomyelia.
motor neuron d. (MND) a general term including progressive spinal muscular atrophy (infantile, juvenile, and adult), amyotrophic lateral sclerosis, progressive bulbar paralysis, and primary lateral sclerosis; frequently a familial d.. SYN: motor system d..
motor system d. SYN: motor neuron d..
mountain d. a term that can mean acute altitude sickness; also used for chronic d. characterized by low oxygen saturation of hemoglobin, due to low partial pressure of oxygen in inspired air plus alveolar hypoventilation that develops in some individuals, especially older people. Polycythemia leads to florid skin color but cyanosis appears on mild exertion, along with dyspnea, fatigue, headache, and mental torpor. A person so afflicted returns to normal shortly after return to lower altitude.
moyamoya d. a cerebrovascular disorder occurring predominantly in the Japanese, in which the vessels of the base of the brain become occluded and revascularized with a fine network of vessels; it occurs commonly in young children and is manifested by convulsions, hemiplegia, mental retardation, and subarachnoid hemorrhage; the diagnosis is made by the angiographic picture. [Jap. addlebrained]
Mucha-Habermann d. SYN: pityriasis lichenoides et varioliformis acuta.
multicore d. nonprogressive congenital myopathy characterized by weakness of proximal muscles, multifocal degeneration of the muscle fibers, and eccentric areas of decreased or absent oxidative enzyme activity in muscles.
Neumann d. SYN: pemphigus vegetans (1) .
neutral lipid storage d. SYN: Dorfman-Chanarin syndrome.
Newcastle d. an acute febrile, and contagious d. of fowls resembling fowl plague, caused by a Paramyxovirus (Newcastle d. virus) and characterized by high infectivity and respiratory and nervous symptoms; it is readily transmissible to humans, in whom it causes a severe but transient conjunctivitis. SYN: Ranikhet d.. [Newcastle–upon–Tyne, England, where first reported]
Nicolas-Favre d. SYN: venereal lymphogranuloma.
Niemann d. SYN: Niemann-Pick d..
Niemann-Pick d. [MIM*257200] lipidosis with accumulation of sphingomyelin in histiocytes in the liver, spleen, lymph nodes, and bone marrow due to a deficiency of sphingomyelinase; associated with hepatosplenomegaly, physical, and mental retardation and neurologic manifestations; macular cherry-red spots may occur at a later stage; occurs most commonly in Ashkenazi Jewish infants and leads to early death; a more benign form may occur in adults. There are several variants: Type A, the classic infantile form; Type B, the visceral form; Type C, the juvenile form; Type D, the Nova Scotia variant; and Type E, the adult form; all are of autosomal recessive inheritance with Types A and B caused by mutation in the acid sphingomyelinase gene (SMPD) on chromosome 11p. SYN: Niemann d., sphingomyelin lipidosis.
Niemann-Pick C1 d. [MIM*257220] a rare inherited lipid storage disorder, affecting viscera and central nervous system, inherited as an autosomal recessive. There are two types of d., with same clinical manifestations and biochemical abnormalities, resulting from abnormalities in two separate genes, NPC-1, the major locus, and NPC-2, the minor locus; then two types have identical clinical and biochemical phenotypes. Cells from NPC patients are defective in the esterification and release of cholesterol from lysosomes; lysosomal sequestration of LDL-derived cholesterol, including delayed down-regulation of LDL uptake and de novo synthesis occur.
nil d. SYN: lipoid nephrosis.
nodular d. esophagostomiasis in herbivores and primates, characterized by nodules in the wall of the large intestine, cecum, and occasionally, the ileum; the nodules are filled with caseous material and result from host response to encystment of the larvae of Oesophagostomum species.
Norrie d. [MIM*310600] congenital bilateral masses of tissue arising from the retina or vitreous and resembling glioma (pseudoglioma), usually with atrophy of iris and development of cataract; associated mental retardation and deafness; X-linked recessive inheritance, caused by mutation in the Norrie d. gene (NDP) on Xp.
notifiable d. a d. that, by statutory requirements, must be reported to the public health or veterinary authorities when the diagnosis is made because of its importance to human or animal health. SYN: reportable d..
oasthouse urine d. [MIM*250900] an autosomal recessively inherited metabolic defect in the absorption of methionine which is converted by intestinal bacteria to α-hydroxybutyric acid; characterized by diarrhea, tachypnea, and marked urinary excretion of α-hydroxybutyric acid (causing an odor like that of an oasthouse). [oast, kiln for drying hops, malt, or tobacco]
occupational d. a morbid condition resulting from exposure to an agent during the usual performance of one's occupation. Cf.:industrial d..
Ofuji d. SYN: eosinophilic pustular folliculitis.
Oguchi d. [MIM*258100] a rare congenital nonprogressive night blindness with diffuse yellow or gray coloration of fundus; after 2 or 3 hours in total darkness, fundus resumes normal color; autosomal recessive inheritance, caused by mutation in either the arrestin gene (SAG) on 2q or the rhodopsin kinase gene (RHOK) on 13q.
Ollier d. SYN: enchondromatosis.
Oppenheim d. SYN: amyotonia congenita.
organic d. a d. in which there are anatomic or pathophysiologic changes in some bodily tissue or organ, in contrast to a functional disorder; particularly one of psychogenic origin.
Ormond d. SYN: retroperitoneal fibrosis.
orphan d. a d. for which no treatment has been developed because of its rarity (affecting no more than 200,000 persons in the U.S.). SEE ALSO: orphan products, under product.
Osgood-Schlatter d. inflammation of the growth center (apophysis) that forms the tibial tubercle. SYN: apophysitis tibialis adolescentium, Schlatter d., Schlatter-Osgood d..
Osler d. SYN: polycythemia vera.
Osler-Vaquez d. SYN: polycythemia vera.
Otto d. a d. characterized by an inward bulging of the acetabulum into the pelvic cavity, resulting in protrusion of the femoral head; found in association with arthritis of the hip joints, usually rheumatoid arthritis. SYN: Otto pelvis, protrusio acetabuli.
Owren d. [MIM*227400] a congenital deficiency of factor V, resulting in prolongation of prothrombin time; bleeding and clotting times are consistently prolonged; autosomal recessive inheritance caused by mutation in the F5 gene on chromosome 1q.
Paas d. a familial skeletal deformation marked by coxa valga, double patella, shortening of the middle and terminal phalanges of fingers and toes, deformities of the elbows, scoliosis, and spondylitis deformans of the lumbar vertebrae; all these manifestations may be unilateral or bilateral.
Paget d. 1. a generalized skeletal d., frequently familial, of older persons in which bone resorption and formation are both increased, leading to thickening and softening of bones ( e.g., the skull), and bending of weight-bearing bones; SYN: osteitis deformans. 2. a d. of elderly women, characterized by an infiltrated, somewhat eczematous lesion surrounding and involving the nipple and areola, and associated with subjacent intraductal cancer of the breast and infiltration of the lower epidermis by malignant cells; 3. SYN: extramammary Paget d..
Panner d. epiphysial osteonecrosis of the capitellum of the humerus. SYN: little league elbow.
paper mill worker's d. extrinsic allergic alveolitis caused by moldy wood pulp containing spores of Alternaria fungi.
parasitic d. a d. due to the presence and vital activity of a parasite, or as a reaction to a parasite.
Parkinson d. SYN: parkinsonism (1) .
Parrot d. 1. pseudoparalysis in infants, due to syphilitic osteochondritis; 2. SYN: marasmus. 3. SYN: psittacosis.
Parry d. SYN: Graves d..
Pavy d. cyclic or recurrent physiologic albuminuria.
pearl-worker's d. inflammatory hypertrophy of the bones affecting grinders of mother-of-pearl.
Pel-Ebstein d. SYN: Pel-Ebstein fever.
Pelizaeus-Merzbacher d. [MIM*311601, *312080, *260600] a sudanophilic leukodystrophy with a tigroid appearance of the myelin resulting from patchy demyelination. Type 1, classic, nystagmus and tremor appearing in the first few months of life, followed by slow motor development sometimes with choreoathetosis, spasticity, optic atrophy and seizures, with death in early adulthood, X-linked recessive inheritance caused by mutation in the proteolipid protein gene (PLP) on Xq; there is an autosomal recessive form as well; type 2, contralateral form with death in months to years after birth, X-linked recessive inheritance; type 3, transitional, with death in the first decade; type 4, adult form associated with involuntary movements, ataxia and hyperreflexia, but without nystagmus; autosomal dominant inheritance [MIM*169500]; type 5, variant forms. Cockayne is sometimes included as a sixth form. SYN: Merzbacher-Pelizaeus d..
Pellegrini d. a calcific density in the medial collateral ligament and/or bony growth on the medial aspect of the medial condyle of the femur. SYN: Pellegrini-Stieda d..
Pellegrini-Stieda d. SYN: Pellegrini d..
pelvic inflammatory d. (PID) acute or chronic suppurative inflammation of female pelvic structures (endometrium, uterine tubes, pelvic peritoneum) due to infection by Neisseria gonorrhoeae, Chlamydia trachomatis, or other organisms, typically a complication of sexually transmitted infection of the lower genital tract, may be precipitated by menstruation, parturition, or surgical procedures including abortion; complications include tubo-ovarian abscess, tubal stenosis with resulting infertility or sterility and heightened risk of ectopic pregnancy, and peritoneal adhesions.
periodic d. any condition or d. in which episodes tend to recur at regular intervals; many such cases are manifestations of familial Mediterranean fever; the cause of the periodicity is usually unknown.
Perthes d. SYN: Legg-Calvé-Perthes d..
Pette-Döring d. SYN: nodular panencephalitis.
Peyronie d. a d. in which plaques or strands of dense fibrous tissue surrounding the corpus cavernosum of the penis cause penile bending and pain on erection; sometimes associated with Dupuytren contracture. SYN: penile fibromatosis, van Buren d..
Pick d. progressive circumscribed cerebral atrophy; a rare type of cerebrodegenerative disorder manifested primarily as dementia, in which there is striking atrophy of portions of the frontal and temporal lobes. SYN: Pick syndrome. [F. Pick]
pink d. SYN: acrodynia (2) .
Plummer d. eponym sometimes applied to hyperthyroidism resulting from a nodular toxic goiter, usually not accompanied by exophthalmos.
polycystic d. of kidneys SYN: polycystic kidney.
polycystic liver d. SYN: polycystic liver.
Pompe d. SYN: type 2 glycogenosis.
Portuguese-Azorean d. SYN: Machado-Joseph d..
Posadas d. SYN: coccidioidomycosis.
posttransplant lymphoproliferative d. a complication of organ transplantation in children; characterized by a mononucleosislike syndrome, tonsillar enlargement, and Epstein-Barr virus seroconversion.
Pott d. SYN: tuberculous spondylitis.
Potter d. SYN: Potter facies.
poultry handler's d. extrinsic allergic alveolitis similar to bird-breeder's lung, caused by inhalation of particulate emanations from domesticated fowl such as chickens and turkeys.
primary d. a d. that arises spontaneously and is not associated with or caused by a previous d., injury, or event, but which may lead to a secondary d..
Pringle d. SYN: adenoma sebaceum.
pseudo-Hurler d. SYN: infantile, generalized G_M1 gangliosidosis.
pulseless d. SYN: Takayasu arteritis.
Purtscher d. SYN: Purtscher retinopathy.
quiet hip d. SYN: Legg-Calvé-Perthes d..
ragpicker's d. SYN: pulmonary anthrax.
ragsorter's d. SYN: pulmonary anthrax.
Ranikhet d. SYN: Newcastle d.. [Ranikhet, town in northern India]
rat-bite d. SYN: rat-bite fever.
Rayer d. SYN: biliary xanthomatosis.
Raynaud d. SYN: Raynaud syndrome.
reactive airway d. SYN: asthma.
Recklinghausen d. of bone SYN: osteitis fibrosa cystica.
Refsum d. [MIM*266500] a rare degenerative disorder due to a deficiency of phytanic acid α-hydroxylase; clinically characterized by retinitis pigmentosa, ichthyosis, demyelinating polyneuropathy, deafness, and cerebellar signs; autosomal recessive inheritance caused by mutation in the gene encoding phytanoyl-CoA hydroxylase (PAHX or PAYH) on chromosome 10p. Infantile Refsum d. [MIM*266510] is an impaired peroxisomal function with accumulation of phytanic acid, pipecolic acid; autosomal recessive inheritance, caused by mutation in the PEX 1 gene on 7q. SYN: heredopathia atactica polyneuritiformis, Refsum syndrome.
Reiter d. SYN: Reiter syndrome.
reportable d. SYN: notifiable d..
rhesus d. sensitization of the mother during pregnancy to Rh factor in fetal blood, leading to erythroblastosis fetalis.
rheumatic d. rheumatism.
rheumatic heart d. d. of the heart resulting from rheumatic fever, chiefly manifested by abnormalities of the valves.
rheumatoid d. rheumatoid arthritis, referring particularly to nonarticular lesions such as subcutaneous nodules.
Ribas-Torres d. a mild form of smallpox. SEE ALSO: variola minor.
rice d. beriberi, the original outbreaks of which were caused by feeding people rice from which the husks had been removed (polished rice), decreasing the vitamin B₁ content of the rice.
Riedel d. SYN: Riedel thyroiditis.
Riga-Fede d. ulceration of the lingual frenum in teething infants, related to abrasion of the tissue against the new central incisors.
Roger d. a congenital cardiac anomaly consisting of a small, isolated, asymptomatic defect of the interventricular septum, often with a loud murmur and definite thrill. SYN: maladie de Roger.
Rokitansky d. 1. SYN: acute massive liver necrosis. 2. SYN: Chiari syndrome.
Romberg d. SYN: facial hemiatrophy.
Rosai-Dorfman d. SYN: sinus histiocytosis with massive lymphadenopathy.
Rougnon-Heberden d. SYN: angina pectoris.
Roussy-Lévy d. [MIM*180800] dominantly inherited disorder consisting of a motor-sensory demyelinating polyneuropathy and a coexisting essential tremor. SYN: Roussy-Lévy syndrome.
runt d. a graft versus host reaction in mice first observed following intravenous injection of allogeneic spleen cells into newborn animals. SYN: wasting d..
salivary gland d. disorder of salivary glands; i.e., Sjögren syndrome.
salivary gland virus d. cytomegalic inclusion d..
Salla d. (sal′ya) an autosomal recessive disorder in which there is a defect in the transport of free sialic acid across lysosomal membranes.
Sandhoff d. [MIM*268800] an infantile form of G_M2 gangliosidosis characterized by a defect in the production of hexosaminidases A and B; it resembles Tay-Sachs d., but occurs predominantly (if not entirely) in non-Jewish children; accumulation of glucoside and ganglioside G_m2, caused by mutation in hexoaminidase B gene (HEX B) on chromosome 5q.
sandworm d. an inflammatory eruption on the inner side of the sole, observed in certain parts of Australia, marked by a patch of erythema spreading in spirals, and disappearing spontaneously; probably a form of creeping eruption similar to larva migrans.
San Joaquin Valley d. SYN: primary coccidioidomycosis.
Schenck d. SYN: sporotrichosis.
Scheuermann d. epiphysial osteonecrosis of adjacent vertebral bodies in the thoracic spine. SYN: adolescent round back, juvenile kyphosis, osteochondritis deformans juvenilis dorsi.
Schilder d. term used to describe at least two separate disorders described by Schilder: 1) Diffuse sclerosis or encephalitis periaxialis diffusa; a nonfamilial disorder affecting primarily children and young adults and characterized by progressive dementia, visual disturbances, deafness, pseudobulbar palsy, and hemiplegia or quadriplegia. Most patients die within a few years of onset; pathologically, there is a large, asymmetric area of myelin destruction, sometimes involving an entire cerebral hemisphere, and typically with extension across the corpus callosum. 2) The leukodystrophies. SYN: encephalitis periaxialis diffusa.
Schindler d. (shind′ler) an autosomal recessive disorder with deficient activity of α-N-acetylgalactosaminidase resulting in accumulation of glycoproteins and other substrates that are deposited in terminal axons, primarily in gray matter.
Schlatter d., Schlatter-Osgood d. SYN: Osgood-Schlatter d..
Scholz d. former eponym for the juvenile form of metachromatic leukodystrophy.
Schüller d. SYN: Hand-Schüller-Christian d..
Schwartz-Jampel d. SYN: myotonic chondrodystrophy.
sclerocystic d. of the ovary SYN: polycystic ovary syndrome.
sea-blue histiocyte d. [MIM*269600] splenomegaly and mild thrombocytopenia, with histiocytes in the bone marrow which contain cytoplasmic granules that stain bright blue; sometimes familial; perhaps a lipidosis; autosomal recessive inheritance.
secondary d. 1. a d. that follows and results from an earlier d., injury, or event; 2. a wasting disorder that follows successful transplantation of bone marrow into a lethally irradiated host; frequently severe and usually associated with fever, anorexia, diarrhea, dermatitis, and desquamation. SEE ALSO: graft versus host d..
self-limited d. a d. process that resolves spontaneously with or without specific treatment.
Senear-Usher d. SYN: pemphigus erythematosus.
serum d. SYN: serum sickness.
Sever d. an osteochondrosis of the heel, probably secondary to microfractures in the bone where the Achilles tendon attaches to the posterior calcaneus; an overuse injury and a common cause of heel pain in older children. SYN: calcaneal apophysitis.
sexually transmitted d. (STD) venereal d..
Shaver d. SYN: bauxite pneumoconiosis.
shimamushi d. SYN: tsutsugamushi d..
sickle cell d. SYN: sickle cell anemia.
sickle cell C d. [MIM*141900] a d. resulting from abnormal sickle-shaped erythrocytes (containing hemoglobins C and S) which appear in response to a lowering of the partial pressure of oxygen; characterized by anemia, crises due to hemolysis or vascular occlusion, chronic leg ulcers and bone deformities, and infarcts of bone or of the spleen.
sickle cell-thalassemia d. anemia clinically resembling sickle cell anemia, in which individuals are compound heterozygous for the sickle cell gene and a thalassemia gene; about 60–80% of hemoglobin is Hb S, up to 20% Hb F, and the remainder Hb A. SYN: microdrepanocytic anemia.
silo-filler's d. a pulmonary lesion produced by oxides of nitrogen due to fresh silage; in its acute form it may lead to death from pulmonary edema or may go on to a subacute or chronic proliferative pulmonary d. sometimes leading to chronic pulmonary invalidism.
Simmonds d. SYN: Sheehan syndrome.
Simons d. SYN: progressive lipodystrophy.
sixth d. SYN: exanthema subitum.
Sjögren d. SYN: Sjögren syndrome.
skinbound d. scleroderma (usually applied to extensive involvement).
slow virus d. a d. that follows a slow, progressive course spanning months to years, frequently involving the central nervous system and ultimately leading to death; examples are visna and maedi of sheep, caused by viruses of the genus Lentivirus (family Retroviridae), and subacute sclerosing panencephalitis, apparently caused by the measles virus. Spongiform encephalopathies, including kuru of humans, scrapie of sheep, and transmissible encephalopathy of mink may also be classified under slow virus d. but are now considered to be prion diseases.
Sneddon-Wilkinson d. SYN: subcorneal pustular dermatosis.
specific d. a d. produced by the action of a special pathogenic microorganism.
Spielmeyer-Sjögren d. cerebral sphingolipidosis, late juvenile type.
Spielmeyer-Stock d. retinal atrophy in amaurotic familial idiocy.
Spielmeyer-Vogt d. cerebral sphingolipidosis, late juvenile type. SYN: Vogt-Spielmeyer d..
stable d. in oncology, less than 25% increase or less than 50% decrease in the size of all tumors.
Stargardt d. [MIM*248200] fundus flavimaculatus initiated with atrophic macular lesions, caused by mutationin the ATP-binding cassette transporter, retina-specific gene (ABCR) on 1p.
startle d. SYN: hyperekplexia.
Steele-Richardson-Olszewski d. SYN: progressive supranuclear palsy.
Steinert d. SYN: myotonic dystrophy.
Still d. a form of juvenile chronic arthritis (formerly called juvenile rheumatoid arthritis) characterized by high fever and signs of systemic illness that can exist for weeks or months before the onset of arthritis.
Stokes-Adams d. SYN: Adams-Stokes syndrome.
stone-mason's d. SYN: silicosis.
storage d. a generic term that includes any accumulation of a specific substance within tissues, generally because of congenital deficiency of an enzyme necessary for further metabolism of the substance; e.g., glycogen-storage diseases.
Strümpell d. 1. SYN: spondylitis deformans. 2. SYN: acute epidemic leukoencephalitis.
Strümpell-Marie d. SYN: ankylosing spondylitis.
Sturge-Weber d. SYN: Sturge-Weber syndrome.
Sulzberger-Garbe d. SYN: exudative discoid and lichenoid dermatitis.
Sutton d. SYN: aphthae major, under aphtha. [R. L. Sutton, Jr.]
Sweet d. SYN: acute febrile neutrophilic dermatosis.
swineherd's d. a leptospirosis caused by a leptospira occurring in those who attend swine or who are occupied in the slaughtering or processing of pork, and characterized by aches and pains throughout the body, fever, headache, dizziness, and nausea.
swine vesicular d. a contagious d. of swine caused by a porcine enterovirus of the family Picornaviridae, closely related to the human enterovirus Coxsackie B-5, and characterized by vesicular lesions and erosions of the epithelium of the mouth, nares, snout, and feet; human infections have been reported in laboratory workers.
swollen belly d. a fatal d. of infants infected with Strongyloides fuelleborni kellyi; appears in localized areas of New Guinea. SYN: swollen belly syndrome.
Sydenham d. SYN: Sydenham chorea.
Sylvest d. SYN: epidemic pleurodynia.
systemic autoimmune diseases a group of connective tissue diseases characterized by the presence of autoantibodies responsible for immunopathologically mediated tissue lesions; systemic lupus erythematosus is the prototype.
systemic febrile diseases generic term for diseases characterized by fever.
Takahara d. SYN: acatalasia.
Takayasu d. SYN: Takayasu arteritis.
Tangier d. SYN: analphalipoproteinemia. [an island in the Chesapeake Bay, home of the family of first cases described]
Taussig-Bing d. SYN: Taussig-Bing syndrome.
Taylor d. diffuse idiopathic cutaneous atrophy.
Tay-Sachs d. a lysosomal storage d., resulting from hexosaminidase A deficiency. The monosialoganglioside is stored in central and peripheral neuronal cells. Infants present with hyperacusis and irritability, hypotonia, and failure to develop motor skills. Blindness with macular cherry red spots and seizures are evident in the first year. Death occurs within a few years. Autosomal-recessive transmission; found primarily in Jewish populations. SYN: infantile G_M2 gangliosidosis.
Thiemann d. SYN: Thiemann syndrome.
third d. SYN: rubella.
Thomsen d. SYN: myotonia congenita.
Thygeson d. SYN: superficial punctate keratitis.
thyrocardiac d. heart d. resulting from hyperthyroidism.
thyrotoxic heart d. cardiac symptoms, signs, and physiologic impairment due to overactivity of the thyroid gland usually due to excessive sympathetic stimulation.
Tommaselli d. hemoglobinuria and pyrexia due to quinine intoxication.
Tornwaldt d. SYN: Tornwaldt cyst.
torsion d. of childhood SYN: dystonia musculorum deformans.
Tourette d. SYN: Tourette syndrome.
Trevor d. SYN: tarsoepiphyseal aclasis.
tropical diseases infectious and parasitic diseases endemic in tropical and subtropical zones, including Chagas d., leishmaniasis, leprosy, malaria, onchocerciasis, schistosomiasis, sleeping sickness, yellow fever, and others; often water- or insect-borne. SEE ALSO: emerging viruses, under virus.
tsutsugamushi d. an acute infectious d., caused by Rickettsia tsutsugamushi and transmitted by Trombicula akamushi and T. deliensis, that occurs in harvesters of hemp in some parts of Japan; characterized by fever, painful swelling of the lymphatic glands, a small blackish scab on the genitals, neck, or axilla, and an eruption of large dark red papules. SYN: akamushi d., flood fever, inundation fever, island d., island fever, Japanese river fever, kedani fever, mite typhus, scrub typhus, shimamushi d., tropical typhus, tsutsugamushi fever.
tunnel d. SYN: ancylostomiasis.
Unna d. SYN: seborrheic dermatitis.
Unverricht d. [MIM*254800] a progressive myoclonic epilepsy; one of the degenerative gray matter disorders characterized by myoclonus and generalized seizures, with progressive neurologic and intellectual decline; age of onset between 8–13 years of age; autosomal recessive inheritance, caused by mutation in the cystatin B gene (CSTB) on 21q22.
Urbach-Wiethe d. SYN: lipoid proteinosis.
vagabond's d. SYN: parasitic melanoderma.
vagrant's d. SYN: parasitic melanoderma.
van Buren d. SYN: Peyronie d..
Vaquez d. SYN: polycythemia vera.
venereal d. any contagious d. acquired during sexual contact; e.g., syphilis, gonorrhea, chancroid.
venoocclusive d. of the liver obliterating endophlebitis of small hepatic vein radicles, described in Jamaican children, associated with ingestion of toxic plant substances in bush tea; causes ascites, which may progress to cirrhosis.
Vincent d. SYN: necrotizing ulcerative gingivitis.
Virchow d. SYN: megacephaly.
virus X d. an old term applied to a number of virus diseases of obscure etiology, e.g., Australian X d. (Murray Valley encephalitis).
Vogt-Spielmeyer d. SYN: Spielmeyer-Vogt d..
Voltolini d. infectious d. of the labyrinth, leading to meningitis in young children.
von Economo d. a unique encephalitis, presumably viral in origin, which followed the influenza pandemic of 1914–1918. Symptoms included ophthalmoplegia and marked somnolence, and in many survivors, the delayed development of Parkinson d.; the basis for postencephalitic Parkinsonism. SYN: encephalitis lethargica, polioencephalitis infectiva.
von Gierke d. SYN: type 1 glycogenosis.
von Recklinghausen d. type 1 neurofibromatosis. See neurofibromatosis.
von Willebrand d. [MIM*193400] a hemorrhagic diathesis characterized by tendency to bleed primarily from mucous membranes, prolonged bleeding time, normal platelet count, normal clot retraction, partial and variable deficiency of factor VIIIR, and possibly a morphologic defect of platelets; autosomal dominant inheritance with reduced penetrance and variable expressivity, caused by mutation in the von Willebrand factor gene (VWF) on 12p. Type III von Willebrand d. is a more severe disorder with markedly reduced factor VIIIR levels. There is a recessive version of this d. [MIM*277480] which has the remarkable property that it represents a mutation at the same locus as the dominant form.
Voorhoeve d. SYN: osteopathia striata.
Wagner d. SYN: hyaloideoretinal degeneration.
wasting d. SYN: runt d..
Weber-Christian d. term used for cases of relapsing febrile nodular nonsuppurative panniculitis (q.v.) of undetermined cause. SYN: relapsing febrile nodular nonsuppurative panniculitis.
Wegner d. SYN: syphilitic osteochondritis.
Weil d. a form of leptospirosis generally caused by Leptospira interrogans serogroup icterohaemorrhagiae, believed to be acquired by contact with the urine of infected rats; characterized clinically by fever, jaundice, muscular pains, conjunctival congestion, and albuminuria; agglutinins regularly appear in the serum. SYN: infectious icterus, infectious jaundice (1) .
Werdnig-Hoffmann d. SYN: spinal muscular atrophy, type I.
Werlhof d. formerly used term for idiopathic thrombocytopenic purpura.
Wernicke d. SYN: Wernicke syndrome.
Werther d. SYN: dermatitis nodularis necrotica.
Wesselsbron d. SYN: Wesselsbron fever.
Whipple d. a rare d. characterized by steatorrhea, frequently generalized lymphadenopathy, arthritis, fever, and cough; many “foamy” macrophages are found in the jejunal lamina propria; caused by Tropheryma whippleii.
white spot d. SYN: morphea guttata.
Whitmore d. SYN: melioidosis.
Wilkie d. SYN: superior mesenteric artery syndrome.
Wilson d. [MIM*277900] 1. a disorder of copper metabolism, characterized by liver cirrhosis, basal ganglia degeneration, neurological manifestations, and deposition of green or golden brown pigment in the periphery of the cornea; the plasma levels of copper and ceruloplasmin are decreased, urinary excretion of copper is increased, and the amounts of copper in the liver, brain, kidneys, and lenticular nucleus are unusually high while cytochrome oxidase is reduced; autosomal recessive inheritance caused by mutation in the copper-transporting ATPase gene (ATP7B) on chromosome 13q. SYN: hepatolenticular degeneration. SEE ALSO: Kayser-Fleischer ring. [S.A.K. Wilson] 2. SYN: exfoliative dermatitis.
Winiwarter-Buerger d. SYN: thromboangiitis obliterans.
Wohlfart-Kugelberg-Welander d. SYN: spinal muscular atrophy, type III.
Wolman d. SYN: cholesterol ester storage d..
woolsorter's d. SYN: pulmonary anthrax.
Woringer-Kolopp d. SYN: pagetoid reticulosis.
X d. one of several viral diseases of obscure etiology.
X-linked lymphoproliferative d. SYN: X-linked lymphoproliferative syndrome.
yellow d. SYN: xanthochromia.
Ziehen-Oppenheim d. SYN: dystonia musculorum deformans.

disengagement
disengagement (dis-en-gaj′ment)

1. The act of setting free or extricating; in childbirth, the emergence of the head from the vulva. 2. Ascent of the presenting part from the pelvis after the inlet has been negotiated. [Fr.]

disequilibrium
disequilibrium (dis-e′kwi-lib′re-um)

A disturbance or absence of equilibrium.
genetic d. a state in the genetic composition of a population which under selection may be expected to change toward an equilibrium or absorbing state.
linkage d. a state involving two loci in which the probability of a joint gamete is not equal to the product of the probabilities of the constituent genes. The difference between these quantities is the increase of the d.; there are many causes of the d..

disfluency
disfluency (dis-floo′en-se)

Inability to produce a smooth flow of speech sounds in connected discourse; the flow of speech is characterized by frequent interruptions and repetitions. [dis- + fluency]

disfluent
disfluent (dis-floo′ent)

Relating to disfluency.

disgerminoma
disgerminoma (dis-jer-mi-no′ma)

SYN: dysgerminoma.

DISH
DISH

Abbreviation for diffuse idiopathic skeletal hyperostosis.

dish
dish

A shallow container, usually concave.
Petri d. a small, shallow, circular d. made of thin glass or clear plastic with a loosely fitting, overlapping cover used especially in microbiology for the cultivation of microorganisms on solid media; it is frequently referred to as a plate.
Stender d. a flat shallow vessel used in staining sections.

disharmony
disharmony (dis-har′mo-ne)

1. The state of being deranged or lacking in orderliness. 2. In a complex sound, the absence of a mathematical relationship among the frequencies of the fundamental tone and its overtones so that the frequencies of the overtones are not whole-number multiples or partials of the frequency of the fundamental tone. The auditory effect has a noisy or unpleasant quality, as opposed to music.
occlusal d. 1. contacts of opposing occlusal surfaces of teeth which are not in harmony with other tooth contacts and with the anatomic and physiologic control of the mandible; 2. occlusions which do not coincide with their respective jaw relations. SEE ALSO: deflective occlusal contact.

DISIDA
DISIDA

Abbreviation for diisopropyl iminodiacetic acid or disofenin.

disimpaction
disimpaction (dis′im-pak′shun)

1. Separation of impaction in a fractured bone. 2. Removal of feces, usually manually, in fecal impaction.

disinfect
disinfect (dis-in-fekt′)

To destroy pathogenic microorganisms in or on any substance or to inhibit their growth and vital activity.

disinfectant
disinfectant (dis-in-fek′tant)

1. Capable of destroying pathogenic microorganisms or inhibiting their growth activity. 2. An agent that possesses this property.
complete d. a d. that kills both vegetative forms and spores.
incomplete d. a d. that kills only the vegetative forms, leaving the spores uninjured.

disinfection
disinfection (dis-in-fek′shun)

Destruction of pathogenic microorganisms or their toxins or vectors by direct exposure to chemical or physical agents.
concurrent d. application of disinfective measures as soon as possible after discharge of infectious material from the body of an infected person, or after soiling of articles with such infectious discharges.
terminal d. application of disinfective measures after the patient has been removed, e.g., by death, or has ceased to be a source of infection.

disinfestation
disinfestation

Physical or chemical process to destroy or remove small undesirable animal forms, particularly arthropods or rodents, present upon the person, clothing, or environment of an individual or domestic animals.

disinhibition
disinhibition (dis′in-hi-bish′un)

1. Removal of an inhibition, such as by a toxic or organic process. 2. Removal of an inhibitory effect by a stimulus, as when a conditioned reflex has undergone extinction but is restored by some extraneous stimulus.

disinsection
disinsection, disinsectization (dis-in-sek′shun, dis′in-sek-ti-za′shun)

Freeing an area from insects. [L. dis-, apart, + insect]

disintegration
disintegration (dis-in-te-gra′shun)

1. Loss or separation of the component parts of a substance, as in catabolism or decay. 2. Disorganization of psychic and behavioral processes. [dis- + L. integer, whole, intact]

disinvagination
disinvagination (dis′in-vaj-i-na′shun)

Relieving an invagination.

disjunction
disjunction (dis-junk′shun)

The normal separation of pairs of chromosomes at the anaphase stage of meiosis I or II. [dis- + L. junctio, a joining, fr. jungo, pp. junctum, to join]

disk
disk [TA]

1. A round, flat plate; any approximately flat circular structure. 2. SYN: lamella (2) . 3. In dentistry, a circular piece of thin paper or other material, coated with an abrasive substance, used for cutting and polishing teeth and fillings. [L. discus; G. diskos, a quoit, d.]
A disks SYN: A bands, under band.
acromioclavicular d. SYN: articular d. of acromioclavicular joint.
Airy d. the image of a circular blur formed by a distant point source of light on the retina because of diffraction by the edge of the pupillary aperture where the diameter of the image decreases as the aperture increases.
anisotropic disks SYN: A bands, under band.
articular d. [TA] a plate or ring of fibrocartilage attached to the joint capsule and separating the articular surfaces of the bones for a varying distance, sometimes completely; it serves to adapt two articular surfaces that are not entirely congruent. SYN: discus articularis [TA] , fibrocartilago interarticularis, fibroplate, interarticular fibrocartilage, intraarticular cartilage (1) .
articular d. of acromioclavicular joint [TA] the articular d. of fibrocartilage usually found between the acromial end of the clavicle and the medial border of the acromion. SYN: discus articularis acromioclavicularis [TA] , acromioclavicular d., Weitbrecht cartilage.
articular d. of distal radioulnar joint [TA] the d. that holds together the distal ends of the radius and ulna; it is attached by its apex to a depression between the styloid process and distal surface of the head of the ulna, and by its base to the ridge separating the ulnar notch from the carpal surface of the radius. SYN: discus articularis radioulnaris distalis [TA] , radioulnar d., radioulnar articular d., triangular cartilage, triangular d. of wrist, triquetrous cartilage (1) .
articular d. of sternoclavicular joint [TA] the fibrocartilaginous d. that subdivides the sternoclavicular joint into two cavities. SYN: discus articularis sternoclavicularis [TA] , sternoclavicular d., sternoclavicular articular d..
articular d. of temporomandibular joint [TA] the fibrocartilaginous plate that separates the joint into upper and lower cavities. SYN: discus articularis temporomandibularis [TA] , mandibular d., temporomandibular articular d..
blastodermic d. the aggregation of blastomeres of a telolecithal ovum after cleavage has occurred.
blood d. SYN: platelet.
Bowman disks disks resulting from transverse segmentation of striated muscular fiber treated with weak acids, certain alkaline solutions, or freezing.
Burlew d. an abrasive-impregnated rubber wheel used in dentistry for polishing. SYN: Burlew wheel.
choked d. SYN: papilledema.
ciliary d. SYN: orbiculus ciliaris.
cone disks membranous disks of flattened sacs about 14 nm thick that occur in the outer segment of cones of the retina.
cuttlefish d. a circle of paper or thin plastic coated with ground cuttlefish bone; used, when attached to a mandrel and rotated by a dental handpiece, for fine smoothing and finishing of dental materials and tooth.
diamond d. a steel d. with the cutting surface(s) covered with fine diamond chips, for use in a dental handpiece.
embryonic d. SYN: germinal d..
emery disks disks of paper or other materials coated with emery powder used to abrade or smooth the surface of teeth or fillings.
germinal d., germ d. the point in a telolecithal ovum where the embryo begins to be formed. SYN: embryonic d., germinal area, area germinativa.
H d. SYN: H band.
hair d. a richly innervated area of skin around a hair follicle, consisting of a thickened layer of epithelial cells in which ramify unmyelinated terminals of a single axon.
Hensen d. SYN: H band.
herniated d. protrusion of a degenerated or fragmented intervertebral d. into the intervertebral foramen with potential compression of a nerve root or into the spinal canal with potential compression of the cauda equina in the lumbar region or the spinal cord at higher levels. SYN: protruded d., ruptured d..
I d. SYN: I band.
intercalated d. a specialized intercellular attachment of cardiac muscle comprising gap junctions, fascia adherens, and occasionally desmosomes.
intermediate d. SYN: Z line.
interpubic d. SYN: interpubic d..
intervertebral d. a d. interposed between the bodies of adjacent vertebrae. It is composed of an outer fibrous part (annulus fibrosus) that surrounds a central gelatinous mass (nucleus pulposus). SYN: discus intervertebralis [TA] , fibrocartilago intervertebralis, intervertebral cartilage.
isotropic d. SYN: I band.
mandibular d. SYN: articular d. of temporomandibular joint.
Merkel tactile d. SYN: tactile meniscus.
Newton d. a d. on which are seven colored sectors, each occupying proportionally the same space as the corresponding primary color in the spectrum; when the d. is rapidly rotated it appears white.
optic d. [TA] an oval area of the ocular fundus devoid of light receptors where the axons of the retinal ganglion cell converge to form the optic nerve head; SYN: discus nervi optici [TA] , blind spot (3) , Mariotte blind spot, optic nerve head, optic papilla, papilla nervi optici, porus opticus.
Placido da Costa d. SYN: keratoscope.
proligerous d. SYN: cumulus oöphorus.
protruded d. SYN: herniated d..
Q disks SYN: A bands, under band.
radioulnar d., radioulnar articular d. SYN: articular d. of distal radioulnar joint.
Ranvier disks tactile nerve endings, of cupped disklike form, in the skin.
rod disks membranous disks of flattened sacs about 14 nm thick that occur in the outer segment of rods of the retina.
ruptured d. SYN: herniated d..
sacrococcygeal d. a thin plate of fibrocartilage interposed between the sacrum and coccyx.
sandpaper disks disks of paper coated with various grits of silica; used to abrade or smooth the surface of teeth or dental materials.
stenopeic d., stenopaic d. a metallic or other opaque d. with a narrow slit through which one looks; used as a test for astigmatism.
sternoclavicular d., sternoclavicular articular d. SYN: articular d. of sternoclavicular joint.
stroboscopic d. a revolving d. that gives successive views of a moving object.
tactile d. SYN: tactile meniscus.
temporomandibular articular d. SYN: articular d. of temporomandibular joint.
transverse d. one of the dark transverse bands seen on examining a striated muscular fiber under the microscope.
triangular d. of wrist SYN: articular d. of distal radioulnar joint.
Z d. SYN: Z line.

diskitis
diskitis (dis-ki′tis)

SYN: discitis.

disko- disko-

See disco-.

diskogram
diskogram (dis′ko-gram)

The graphic record, usually radiographic, of diskography.

diskography
diskography (dis-kog′ra-fe)

Historically, radiographic demonstration of intervertebral disk by injection of contrast media into the nucleus pulposus. [disco- + G. grapho, to write]

dislocate
dislocate (dis′lo-kat)

To luxate; to put out of joint.

dislocatio
dislocatio (dis-lo-ka′she-o)

SYN: dislocation. [L.]
d. erecta a subglenoid dislocation of the shoulder in which the humerus is in an abducted postion with the head of the humerus displaced inferiorly.

dislocation
dislocation (dis-lo-ka′shun)

Displacement of an organ or any part; specifically a disturbance or disarrangement of the normal relation of the bones at a joint. The direction of the d. is determined by the position of the distal part of the articulation. SYN: dislocatio, luxation (1) . [L. dislocatio, fr. dis-, apart, + locatio, a placing]
d. of articular processes complete d. of one or both articular processes, usually with overriding of the inferior articular process of the vertebra above into a position anterior to the superior articular process of the vertebra below. SYN: locked facets.
arytenoid d. separation of the cricoarytenoid joint with subluxation of the arytenoid cartilage. SYN: arytenoid subluxation.
closed d. a d. not complicated by an external wound. SYN: simple d..
compound d. SYN: open d..
fracture d. d. associated with or accompanied by a fracture of one of the bones forming the articulation.
Kienböck d. d. of semilunar bone.
open d. a d. complicated by a wound opening from the surface down to the affected joint. SYN: compound d..
perilunar d. d. of carpal bones around the lunate, which remains in its normal anatomic position in relation to the radius; distinguish from d. of lunate, Kienböck d..
simple d. SYN: closed d..

dismember
dismember (dis-mem′ber)

1. To amputate an arm or leg. 2. To divide the body (corpus) in parts.

dismutase
dismutase (dis′mu-tas)

Generic name for enzymes catalyzing the reaction of two identical molecules to produce two molecules in differing states of oxidation ( e.g., superoxide d.) or of phosphorylation ( e.g., glucose-1-phosphate phosphodismutase).

dismutation
dismutation (dis′mu-ta′shun)

A reaction involving a single substance but producing two products; e.g., two molecules of acetaldehyde may react, producing an oxidation product (acetic acid) and a reduction product (ethyl alcohol).

disobliteration
disobliteration (dis′ob-lit-er-a′shun)

Opening of a pathologically closed channel.

disofenin
disofenin (di′so-fen-in)

SYN: diisopropyl iminodiacetic acid.

disomic
disomic (di-so′mik)

Relating to disomy.

disomy
disomy (di′so-me)

1. The state of an individual or cell having two members of a pair of homologous chromosomes; the normal state in humans, in contrast to monosomy and trisomy. 2. An abnormal chromosome represented twice in a single cell. [G. dis, two, + soma, body]

disopromine
disopromine (di-so-pro′men)

SYN: diisopromine.

disopyramide
disopyramide (di-so-pir′a-mid)

An antiarrhythmic drug resembling quinidine with substantial anticholinergic properties.

disorder
disorder (dis-or′der)

A disturbance of function, structure, or both, resulting from a genetic or embryonic failure in development or from exogenous factors such as poison, trauma, or disease.
adjustment disorders 1. a group of mental and behavioral disorders in which the development of symptoms is related to the presence of some environmental stressor or life event and is expected to remit when the stress ceases; 2. a d. whose essential feature is a maladaptive reaction to an identifiable psychological stress, or stressors, that occurs within weeks of the onset of the stressors and persists for up to six months; the maladaptive nature of the reaction is indicated by impairment in occupational (including school) functioning, or in usual social activities or relationships with others, or with symptoms that are in excess of a normal or expectable reaction to the stressor.
affective disorders a group of mental disorders characterized by a disturbance in mood.
antisocial personality d. 1. an enduring and pervasive pattern characterized by continuous and chronic antisocial behavior with disregard for and violation of the rights and safety of others, beginning before the age of 15; early childhood signs include chronic lying, stealing, fighting, and truancy; in adolescence there may be unusually early or aggressive sexual behavior, excessive drinking, and use of illicit drugs, such behavior continuing in adulthood. 2. a DSM diagnosis that is established when the specified criteria are met.
anxiety disorders a group of interrelated mental illnesses involving anxiety reactions in response to stress. The types include: 1) generalized anxiety, by far the most prevalent condition, which strikes slightly more females than males, mostly in the 20–35 age group; 2) panic d., in which a person suffers repeated panic attacks. Some 2–5% of Americans are subject to this ailment, about twice as many women as men; 3) obsessive-compulsive d., afflicting 2–3% of the U.S. population; 4) posttraumatic stress d., most frequent among combat veterans or survivors of major physical trauma; and 5) the phobias ( e.g., fear of snakes, crowds, confinement, heights, etc.), which on a minor scale affect about one in eight people in the U.S. See neurosis.
articulation disorders errors in pronunciation including phoneme omissions, substitutions, distortions, and additions.
Asperger d. 1. a pervasive developmental d. characterized by severe and enduring impairment in social skills and restrictive and repetitive behaviors and interests, leading to impaired social and occupational functioning but without significant delays in language development. 2. a DSM diagnosis that is established when the specified criteria are met.
asthenic personality d. SYN: asthenic personality.
attention deficit d. a d. of attention, organization and impulse control appearing in childhood and sometimes persisting to adulthood. Hyperactivity may be a feature, but is not necessary for the diagnosis.
attention deficit hyperactivity d. 1. a d. of childhood and adolescence manifested at home, in school, and in social situations by developmentally inappropriate degrees of inattention, impulsiveness, and hyperactivity. 2. a DSM diagnosis that is established when the specified criteria are met. SYN: hyperactive child syndrome.
autistic d. 1. a severe form of pervasive developmental d.. SEE ALSO: autism, infantile autism. 2. a DSM diagnosis that is established when the specified criteria are met. See autism, infantile autism.
avoidant d. of adolescence See avoidant d. of childhood.
avoidant d. of childhood a mental d. occurring in childhood or adolescence characterized by an excessive shrinking away from contact with people who are unfamiliar.
avoidant personality d. 1. an enduring and pervasive pattern in adulthood characterized by hypersensitivity to rejection, humiliation, shame, feelings of inadequacy resulting in social inhibition, and an unwillingness to enter into relationships without unusually strong guarantees of uncritical acceptance. 2. a DSM diagnosis that is established when the specified criteria are met. SYN: avoidant personality.
behavior d. general term used to denote mental illness or psychological dysfunction, specifically those mental, emotional, or behavioral subclasses for which organic correlates do not exist. See antisocial personality d..
bipolar d. an affective d. characterized by the occurrence of alternating periods of euphoria (mania) and depression. SYN: manic-depressive psychosis.
body dysmorphic d. 1. a psychosomatic (somatoform) d. characterized by preoccupation with some imagined defect in appearance in a normal-appearing person. 2. a DSM diagnosis that is established when the specified criteria are met. SYN: dysmorphophobia.
borderline personality d. 1. an enduring and pervasive pattern that begins by early adulthood and is characterized by impulsivity and unpredictability, unstable interpersonal relationships, inappropriate or uncontrolled affect, especially anger, identity disturbances, rapid shifts of mood, suicidal acts, self-mutilations, job and marital instability, chronic feelings of emptiness or boredom, and intolerance of being alone. 2. a DSM diagnosis that is established when the specific criteria are met.
character d. an older term referring to a group of behavioral disorders, now replaced by a more general term, personality d..
conduct d. 1. a mental d. of childhood or adolescence characterized by a persistent pattern of violating societal norms and the rights of others; children with the d. may exhibit physical aggression, cruelty to animals, vandalism and robbery, along with truancy, cheating, and lying. 2. a DSM diagnosis that is established when the specified criteria are met. See antisocial personality d..
conversion d. 1. a mental d. in which an unconscious emotional conflict is expressed as an alteration or loss of physical functioning, usually controlled by the voluntary nervous system. 2. a DSM diagnosis that is established when the specified criteria are met.
cumulative trauma disorders (CTD) chronic disorders involving connective tissue (muscles, tendons) and nerve, often resulting from work-related physical activities. SYN: repetitive strain disorders, repetitive stress disorders.
cyclothymic d. SYN: cyclothymia.
cyclothymic personality d. SYN: cyclothymic personality.
delusional d. a severe mental d. characterized by the presence of delusions. The delusions may be related to paranoid, grandiose, somatic, or erotic themes.
dependent personality d. 1. an enduring and pervasive pattern in adulthood characterized by submissive and clinging behavior and excessive reliance on others to meet one's emotional, social, or economic needs. 2. a DSM diagnosis that is established when the specified criteria are met. SYN: dependent personality.
depersonalization d. 1. a d. characterized by persistent or recurrent experiences of detachment from one's mental processes or body, as if one is an automaton, an outside observer, or in a dream; reality testing remains intact and there is clinically significant distress impairment. 2. a DSM diagnosis is established when the specified criteria are met.
dissociative disorders a group of mental disorders characterized by disturbances in the functions of identity, memory, consciousness, or perception of the environment; this group includes dissociative (older term, psychogenic) amnesia, dissociative fugue, dissociative identity (older term, multiple personality) d., and depersonalization d..
dissociative identity d. 1. a d. in which two or more distinct conscious personalities alternately prevail in the same person, sometimes without any one personality being aware of the other(s). 2. a DSM diagnosis that is established when the specified criteria are met. SYN: multiple personality.
dysthymic d. 1. a chronic disturbance of mood characterized by mild depression or loss of interest in usual activities. See depression. 2. a DSM diagnosis is established when the specified criteria are met.
eating disorders a group of mental disorders including anorexia nervosa, bulimia nervosa, pica, and rumination d. of infancy.
emotional d. mental illness, behavior d..
erotomanic d. the false belief that one is loved by another such as a movie star or a casual acquaintance.
factitious d. a mental d. in which the individual intentionally produces symptoms of illness or feigns illness for psychological reasons rather than for environmental goals.
familial bipolar mood d. bipolar mood d. commonly inherited as an autosomal dominant [MIM*125480] trait and also occasionally as an X-linked one [MIM*309200].
functional d. a d. characterized by physical symptoms with no known or detectable organic basis. See behavior d., neurosis. SYN: functional disease, functional illness.
gender identity disorders 1. a mental d. in children, adolescents, or adults characterized by a strong and enduring cross-gender identification that manifests in insistence that one is, or desires to be, the other sex; this d. involves persistent discomfort with one's assigned sex or the gender role of one's sex, such that there is clinically significant distress or impairment in functioning, often leading to adopting to various degrees the gender role of the other sex. 2. a DSM diagnosis that is established when the specific criteria are met. SEE ALSO: transsexualism.
generalized anxiety d. 1. chronic, repeated episodes of anxiety reactions; a psychological d. in which anxiety or morbid fear and dread accompanied by autonomic changes are prominent features. 2. a DSM diagnosis that is established when the specified criteria are met. See anxiety.
grandiose type of paranoid d. a delusion in which the person believes that he or she possesses some great but unrecognized talent or insight, or has made an important discovery, with subsequent efforts toward official or public recognition.
histrionic personality d. 1. an enduring and pervasive pattern of behavior in adulthood characterized by excessive, dramatic, and shallow emotionality; attention-seeking; and demands for approval and reassurance, beginning in early childhood and present in a variety of contexts. 2. a DSM diagnosis that is established when the specified criteria are met. SYN: hysterical personality d., hysterical personality.
hysterical personality d. SYN: histrionic personality d..
identity d. a mental d. in which one suffers severe distress regarding one's ability to reconcile aspects of the self into a coherent acceptable sense of self.
immune complex d. SYN: immune complex disease.
immunoproliferative disorders disorders in which there is a continuing proliferation of cells of the immune system that can result in γ-globulin abnormalities such as in chronic lymphocytic leukemia, “macroglobulinemias,” and multiple myeloma.
impulse control d. a group of mental disorders characterized by a person's failure to resist an impulse to perform some act harmful to self or to others; includes pathologic gambling, pedophilia, kleptomania, pyromania, trichotillomania, intermittent and isolated explosive disorders.
induced psychotic d. a severe mental d. brought about by a toxic agent such as a drug or hallucinogen. See psychosis.
intermittent explosive d. 1. a d. that may begin in early childhood, or following head injury at any age, characterized by repeated acts of violent, aggressive behavior in otherwise normal persons that is markedly out of proportion to the event that provokes it. 2. a DSM diagnosis that is established when the specified criteria are met. SYN: dyscontrol, episodic dyscontrol syndrome.
internet addiction d. a posited clinical syndrome involving excessive time spent “surfing the net”; without clearly established criteria or etiology.
ion channel disorders a number of diseases, mostly inherited and episodic in nature, caused by dysfunction of the calcium, chloride, potassium, or sodium channels of nerve or muscle; the inherited myotonias and periodic paralyses are included in this category; there is usually dominant inheritance, with the primary defect due to mutations of gene encoding on locus 7q32, 17q, or 1q31-32. SYN: channelopathies.
isolated explosive d. a d. of impulse control characterized by a single episode of failure to resist a violent, externally directed act which had serious impact on others.
jealous type of paranoid d. the false belief that one's spouse or lover is unfaithful, leading to repeated confrontation, or the taking of extraordinary steps to intervene in the imagined infidelity.
late luteal phase dysphoric d. SYN: premenstrual syndrome.
LDL receptor d. abnormality in clearance of LDL from the plasma due to abnormality in LDL receptor activity; causes hypercholesterolemia.
lymphoplasmacellular disorders term used to refer to a group of disorders including plasmacytoma, multiple myeloma, lymphoplasmacytic lymphoma, MALT lymphoma, and amyloidosis.
major mood d. See bipolar d., affective psychosis, endogenous depression, dysthymia, manic-depressive d..
manic-depressive d. obsolete term for bipolar d..
mental d. a psychological syndrome or behavioral pattern that is associated with subjective distress and/or objective impairment. SEE ALSO: mental illness, behavior d..
mitochondrial disorders a group of diverse hereditary disorders caused by genetic mutation of mitochrondrial DNA; includes ragged red fiber myopathy; progressive external ophthalmoplegia; Leigh syndrome; myoclonic epilepsy with ragged red fiber myopathy (MERRF); mitochondrial myopathy, encephalopathy, lacta cidosis, and stroke (MELAS); and Lieber optic neuropathy.
mood disorders a group of mental disorders involving a disturbance of mood, accompanied by either a full or partial manic or depressive syndrome that is not due to any other mental d.. Mood refers to a prolonged emotion that colors the whole psychic life; it generally involves either depression or elation; e.g., manic episode, major depressive episode, bipolar disorders, and depressive d. (see separate entries for each).
multiple personality d. older term for dissociative identity d..
narcissistic personality d. 1. a pervasive pattern in adulthood of self-centeredness, self-importance, lack of empathy for others, sense of entitlement, and viewing others largely as objects to meet one's needs, manifested in a variety of contexts. 2. a DSM diagnosis that is established when the specified criteria are met.
neuropsychologic d. cerebral dysfunction from any physical cause manifested by changes in mood, behavior, perception, memory, cognition, or judgment and/or psychophysiology.
neurotic d. SYN: neurosis.
obsessive-compulsive d. 1. a type of anxiety d. whose essential feature is recurrent obsessions, persistent, intrusive ideas, thoughts, impulses or images, or compulsions (repetitive, purposeful, and intentional behaviors performed in response to an obsession) sufficiently severe to cause marked distress, be time-consuming, or significantly interfere with the individual's normal routine, occupational functioning, or usual social activities or relationships with others. 2. a DSM diagnosis that is established when the specified criteria are met. SEE ALSO: obsessive-compulsive personality d..
obsessive-compulsive personality d. 1. a pervasive pattern in adulthood characterized by unattainable perfectionism; preoccupation with rules, details, and orderliness; unreasonable attempts to control others; excessive devotion to work; and rumination to the point of indecisiveness, all at the expense of flexiblity, openness, and efficiency. 2. a DSM diagnosis that is established when the specified criteria are met. SYN: compulsive personality, obsessive personality, obsessive-compulsive personality.
oppositional d. SYN: oppositional defiant d..
oppositional defiant d. 1. a d. of childhood or adolescence characterized by a recurrent pattern of negativistic, hostile, and disobedient behavior toward authority figures. 2. a DSM diagnosis that is established when the specified criteria are met. SYN: oppositional d..
organic mental d. a psychological, cognitive, or behavioral abnormality associated with transient or permanent dysfunction of the brain, usually characterized by the presence of an organic brain syndrome.
overanxious d. a mental d. of childhood or adolescence marked by excessive worrying and fearful behavior not related specifically to separation or due to recent stress, now included within generalized anxiety d..
panic d. recurrent panic attacks that occur unpredictably. See generalized anxiety d..
paranoid d. SYN: persecutory type of paranoid d..
paranoid personality d. 1. a personality d. that is less debilitating than is the paranoid or delusional paranoid d.; the essential feature is a pervasive and unwarranted tendency, beginning in early adulthood and present in a variety of contexts, to misinterpret the actions of others as deliberately exploitive, harmful, demeaning, or threatening. 2. a DSM diagnosis that is established when the specified criteria are met. SYN: paranoid personality.
persecutory type of paranoid d. one of the most common of the types of paranoid disorders, it involves a single theme or series of connected themes, such as being conspired against, cheated, spied on, followed, poisoned or drugged, maligned, harassed, or obstructed in the pursuit of long-term goals; small slights may be exaggerated and become the focus of a delusional system. See paranoia. Cf.:paranoid personality d.. SYN: paranoid d..
personality d. general term for a group of behavioral disorders characterized by usually lifelong ingrained maladaptive patterns of subjective internal experience and deviant behavior, lifestyle, and social adjustment, which patterns may manifest in impaired judgement, affect, impulse control and interpersonal functioning.
pervasive developmental d. a group of mental disorders of infancy, childhood, or adolescence characterized by distortions in the acquisition of the multiple basic psychologic funtions necessary for the elaboration of social skills, language skills, and imagination; also characterized by restricted or stereotypical activities and interests. SEE ALSO: Rett syndrome, Asperger d..
plasma iodoprotein d. familial goiter.
posttraumatic stress d. 1. development of characteristic symptoms following a psychologically traumatic event that is generally outside the range of usual human experience; symptoms include numbed responsiveness to environmental stimuli, a variety of autonomic and cognitive dysfunctions, and dysphoria. 2. a DSM diagnosis that is established when the specified criteria are met.
premenstrual dysphoric d. 1. a pervasive pattern occurring during the last week of the luteal phase in most menstrual cycles for at least a year and remitting within a few days of the onset of the follicular phase, with some combination of depressed mood, mood lability, marked anxiety, or irritability; various specific physical symptoms; and significant functional impairment; the symptoms are comparable in severity to those seen in a major depressive episode, distinguishing this d. from the far more common premenstrual syndrome. SEE ALSO: premenstrual syndrome. 2. a specified set of criteria in the DSM, proposed for the purpose of futher research.
psychogenic pain d. a d. in which the principal complaint is pain that is out of proportion to objective findings and that is related to psychological factors.
psychosomatic d., psychophysiologic d. a d. characterized by physical symptoms of psychic origin, usually involving a single organ system innervated by the autonomic nervous system; physiological and organic changes stem from a sustained disturbance.
psychotic d. SYN: psychosis.
reactive attachment d. 1. a mental d. of infancy or early childhood characterized by disturbed social relatedness; thought to be caused by grossly pathologic care. 2. a DSM diagnosis that is established when the specified criteria are met.
REM behavior d. a d. characterized by lack of the atonia of voluntary muscles that normally occurs in REM sleep.
repetitive strain disorders SYN: cumulative trauma disorders.
repetitive stress disorders SYN: cumulative trauma disorders.
rumination d. 1. a mental d. occurring in infancy characterized by repeated regurgitation of food, usually accompanied by weight loss or failure to gain weight. 2. a DSM diagnosis that is established when the specified criteria are met.
schizoid personality d. 1. an enduring and pervasive pattern of behavior in adulthood characterized by social withdrawal, emotional coldness or aloofness or restriction, and indifference to others. 2. a DSM diagnosis that is established when the specific criteria are met. SYN: schizoid personality.
schizophreniform d. (skiz′o-fren′i-form) 1. a d. whose essential features are identical with those of schizophrenia, with the exception that the duration including prodromal, active, and residual phases is less than six months. 2. a DSM diagnosis that is established when the specified criteria are met.
schizotypal personality d. 1. an enduring and pervasive pattern of behavior in adulthood characterized by discomfort with and reduced capacity for close relationships, cognitive or perceptual distortions, and eccentric behavior. 2. a DSM diagnosis that is established when the specific criteria are met. SYN: schizotypal personality.
seasonal affective d. (SAD) a depressive mood d. that occurs at approximately the same time year after year and spontaneously remits at the same time each year. The most common type is winter depression and it is characterized by morning hypersomnia, low energy, increased appetite, weight gain, and carbohydrate craving, all of which remit in the spring.
separation anxiety d. 1. a mental d. occurring in childhood characterized by excessive anxiety when the child is separated from someone to whom the child is attached, usually a parent. 2. a DSM diagnosis that is established when the specified criteria are met.
sexual disorders a group of behavioral and psychophysiologic disorders in which there is symptomatic variability in sexual functioning, including either the eroticized behavior associated with sexual activity (the paraphilias) or with disturbances of desire, arousal, and orgasm.
shared psychotic d. SYN: folie à deux.
sleep terror d. night terrors.
somatization d. 1. a mental d. characterized by presentation of a complicated medical history and of physical symptoms referring to a variety of organ systems, but without a detectable or known organic basis. See conversion, hysteria, Briquet syndrome. 2. a DSM diagnosis that is established when the specified criteria are met.
somatoform d. a group of disorders in which physical symptoms suggesting physical disorders for which there are no demonstrable organic findings or known physiologic mechanisms, and for which there is positive evidence, or a strong presumption that the symptoms are linked to psychological factors; e.g., hysteria, conversion d., hypochondriasis, pain d., somatization d., body dysmorphic d., and Briquet syndrome.
substance abuse disorders a group of mental disorders in which maladaptive behavioral and biologic changes are associated with regular use of alcohol, drugs, and related substances that affect the central nervous system and result in failure to meet significant obligations in personal and social functioning.
substance dependence d. a maladaptive pattern of use of alcohol, drugs, or other substances, with tolerance and/or withdrawal symptoms, drug-seeking behavior, and lack of success in discontinuation of use, to the detriment of social, interpersonal, and occupational activities.
substance-induced organic mental disorders mental disorders caused by use of drugs, e.g., cocaine, alcohol, etc.
thought d. SYN: thought process d..
thought process d. an intellectual function symptom of schizophrenia, manifested by irrelevance and incoherence of verbal productions ranging from simple blocking and mild circumstantiality to total loosening of associations. SYN: thought d..
triple repeat disorders a group of hereditary disorders in which a gene mutation on a specific chromosome produces an abnormal form of protein terminated by a long chain of amino acid glutamate repeats; includes Huntington disease, Kennedy disease, Machado-Joseph disease, myotonic dystrophy, fragile X syndrome, and some spinal cerebellar disorders.
visceral d. an obsolete term used in reference to psychosomatic d..

disorganization
disorganization (dis-or′gan-i-za′shun)

Destruction of an organ or tissue with consequent loss of function.

disorientation
disorientation (dis′or-e-en-ta′shun)

Loss of the sense of familiarity with one's surroundings (time, place, and person); loss of one's bearings.

disparate
disparate (dis′pa-rat)

Unequal; not alike. [L. disparo, pp. -atus, to separate, fr. paro, to prepare]

disparity
disparity (dis-par′i-te)

The condition of being disparate. [L. dispar, dissimilar]
fixation d. the amount of heterophoria possible with fusion present.
retinal d. the slight difference in retinal images that arises because of the lateral separation of the two eyes that stimulates stereoscopic vision.

dispensary
dispensary (dis-pen′ser-e)

1. A physician's office, especially the office of one who dispenses medicines. 2. The office of a hospital pharmacist, where medicines are given out on physicians' orders. 3. An outpatient department of a hospital. [L. dis-penso, pp. -atus, to distribute by weight, fr. penso, to weigh]

Dispensatory
Dispensatory (dis-pen′sa-to-re)

A work originally intended as a commentary on the Pharmacopeia, but now more of a supplement to that work, which contains an account of the sources, mode of preparation, physiologic action, and therapeutic uses of most of the agents, official and nonofficial; used in the treatment of disease. [L. dispensator, a manager, steward; see dispensary]

dispense
dispense (dis-pens′)

To give out medicine and other necessities to the sick; to fill a medical prescription.

dispermy
dispermy, dispermia (di′sper-me, di-sperm′e-a)

Entrance of two spermatozoa into one ovum.

dispersal
dispersal (dis-per′sal)

SYN: dispersion (1) .
flash d. the property of rapid disintegration of a tablet when placed on the tongue.

disperse
disperse (dis-pers′)

To dissipate, to cause disappearance of, to scatter, to dilute.

dispersion
dispersion (dis-per′zhun)

1. The act of dispersing or of being dispersed. SYN: dispersal. 2. Incorporation of the particles of one substance into the mass of another, including solutions, suspensions, and colloidal dispersions (solutions). 3. Specifically, what is usually called a colloidal solution. 4. The extent or degree in which values of a statistical frequency distribution are scattered about a mean or median value. [L. dispersio]
coarse d. SYN: suspension (4) .
colloidal d. SYN: colloidal solution.
molecular d. d. in which the dispersed phase consists of individual molecules; if the molecules are of less than colloidal size, the result is a true solution.
optic rotatory d. (ORD) the change in optic rotation with the wavelength of the incident monochromatic polarized light; the displacement of the former from zero within the absorption band is known as the Cotton effect.
temporal d. asynchronous repolarization of myocardial fibers that predisposes to abnormal current flow and ectopic rhythms (especially with bradyarrhythmias or ventricular tachyarrhythmias).

dispersity
dispersity (dis-per′si-te)

The extent to which the dimensions of particles have been reduced in colloid formation.

dispersoid
dispersoid (dis-per′soyd)

A colloidal solution in which the dispersed phase can be concentrated by centrifugation. SYN: dispersion colloid, molecular dispersed solution.

dispireme
dispireme (di-spi′rem)

The double chromatin skein in the telophase of mitosis. [G. di-, twice, + speirema, coil, convolution]

displaceability
displaceability (dis-plas-a-bil′i-te)

The capability of, or susceptibility to, displacement.
tissue d. the property of tissue that permits it to be moved from an initial or relaxed position or form. SYN: compression of tissue.

displacement
displacement (dis-plas′ment)

1. Removal from the normal location or position. 2. The adding to a fluid (particularly a gas) in an open vessel one of greater density whereby the first is expelled. 3. In chemistry, a change in which one element, radical, or molecule is replaced by another, or in which one element exchanges electric charges with another by reduction or oxidation. 4. In psychiatry, the transfer of impulses from one expression to another, as from fighting to talking.
affect d. a shift of feeling from the object originally arousing it to some associated object.
mesial d. SYN: mesioversion.
tissue d. the change in the form or position of tissues as a result of pressure.

display
display

differential d. the use of RT-PCR-based technologies to amplify mRNA from specific cells or tissues and then to compare them directly with amplified mRNA from another cell or tissue.

disproportion
disproportion (dis-pro-por′shun)

Lack of proportion or symmetry.
cephalopelvic d. a condition in which the fetal head is too large to traverse the maternal pelvis.

Disse
Disse

Josef, German anatomist, 1852–1912. See D. space.

dissect
dissect (di-sekt′, di-)

1. To cut apart or separate the tissues of the body for study. 2. In an operation, to separate the different structures along natural lines by dividing the connective tissue framework. [L. dis-seco, pp. -sectus, to cut asunder]

dissection
dissection (di-sek′shun, di-)

The act of dissecting. SYN: anatomy (3) [TA] , necrotomy (1) .
aortic d. a pathologic process, characterized by splitting of the media layer of the aorta, which leads to formation of a dissecting aneurysm. Classified according to location as follows: type I involves the ascending aorta, transverse arch, and distal aorta; type II is confined to the ascending aorta; type III extends distally in the descending aorta usually from a starting point just distal to the left subclaviar artery.
functional neck d. operation to remove metastases to the lymph nodes of the neck; differs from a radical neck d. by preserving any of the following structures: the sternocleidomastoid muscle, the spinal accessory nerve, and the internal jugular vein. SYN: limited neck d..
limited neck d. SYN: functional neck d..
radical neck d. an operation for the removal of metastases to the lymph nodes of the neck in which all of the tissue is removed between the superficial and the deep cervical fascia from the mandible to the clavicle. SEE ALSO: functional neck d..

dissector
dissector (dis-ek′ter)

1. One who dissects. 2. A written guide for dissection. 3. Instrument for dissecting.

disseminated
disseminated (di-sem′i-na-ted)

Widely scattered throughout an organ, tissue, or the body. [L. dissemino, pp. -atus, to scatter seed, fr. semen (-min-), seed]

dissepiment
dissepiment (di-sep′i-ment)

A separating tissue, partition, or septum. [L. dis- sepio, pp. -septus, to divide by a fence]

dissimilation
dissimilation (di-sim-i-la′shun)

1. SYN: disassimilation. 2. SYN: catabolism.

dissimulation
dissimulation (di-sim-u-la′shun)

Concealment of the truth about a situation, especially about a state of health or during a mental status examination, as by a malingerer or someone with a factitious disorder. [L. dissimulatio, fr. dissimulo, to feign, fr. dis, apart, + simillis, same]

dissociation
dissociation (di-so-se-a′shun, -she-a′shun)

1. Separation, or a dissolution of relations. SYN: disassociation. 2. The change of a complex chemical compound into a simpler one by any lytic reaction, by ionization, by heterolysis, or by homolysis. 3. An unconscious separation of a group of mental processes from the rest, resulting in an independent functioning of these processes and a loss of the usual associations; for example, a separation of affect from cognition. See multiple personality. 4. A state used as an essential part of a technique for healing in psychology and psychotherapy, for instance in hypnotherapy or the neurolinguistic programming technique of time-line therapy. SEE ALSO: Time-Line therapy. 5. The translocation between a large chromosome and a small supernumerary one. 6. Separation of the nuclear components of a heterokaryotic dikaryon. [L. dis-socio, pp. -atus, to disjoin, separate, fr. socius, partner, ally]
albuminocytologic d. increased protein in the cerebrospinal fluid without increase in cell count, characteristic of the Guillain-Barré syndrome; it is also associated with spinal block and with intracranial neoplasia, and is seen in the last phases of poliomyelitis.
atrial d. mutually independent beating of the two atria or of parts of the atria.
atrioventricular d. (AVD) , AV d. 1. any situation in which atria and ventricles are activated and contract independently, as in complete AV block; 2. more specifically, the d. between atria and ventricles that results from slowing of the atrial pacemaker or acceleration of the ventricular pacemaker at nearly equal (rarely equal) rates, each depolarizing its own chamber, thus interfering with depolarization by the other (interference-d.).
complete atrioventricular d., complete AV d. aV d. not interrupted by ventricular captures. SYN: complete AV block (2) , third degree AV block.
electromechanical d. persistence of electrical activity in the heart without associated mechanical contraction; often a sign of cardiac rupture. SYN: pulseless electrical activity.
incomplete atrioventricular d., incomplete AV d. aV d. interrupted by ventricular captures.
interference d. the simultaneous operation of two separate cardiac pacemaking foci that are unassociated because of interference (a normal physiologic phenomenon) due to rendering their respective territories refractory to each other. Usually atrioventricular d. is indicated, the rates being quite close to each other with the atrial rate slightly slower than that of the pacemaker in control of the ventricles. Capture is in either direction, usually the ventricle by the atrium, in incomplete d.. h SYN: d. by interference.
d. by interference SYN: interference d..
isorhythmic d. AV d. characterized by equal or closely similar atrial and ventricular rates.
light-near d. SYN: pupillary light-near d..
longitudinal d. d. between parallel chambers of the heart, as between one atrium and the other or between one ventricle and the other, in contrast to d. between atria and ventricles.
pupillary light-near d. pupillary light-near d..
sleep d. SYN: sleep paralysis.
syringomyelic d. loss of pain and temperature sensation with relative retention of tactile sensation, related to a cavity in the central portion of the cord interrupting the decussation of nerve fibers.
tabetic d. loss of proprioceptive sensation with retained pain and temperature sensation due to involvement of the posterior columns of the spinal cord.
visual-kinetic d. the neurolinguistic programming process of removing a synesthesia from a person's internal experience. SEE ALSO: neurolinguistic programming.

dissolve
dissolve (di-zolv′)

To change or cause to change from a solid to a dispersed form by immersion in a fluid of suitable properties. [L. dis-solvo, pp. -solutus, to loose asunder, to d.]

dissonance
dissonance (di′so-nans)

In social psychology and attitude theory, an aversive state which arises when an individual is minimally aware of inconsistency or conflict within himself. See cognitive d. theory. [L. dissonus, discordant, confused]
cognitive d. a motivational state studied by social and clinical psychologists which exists when a person's attitudes, perceptions, and related cognitive state are inconsistent with each other, e.g., hating blacks but admiring Martin Luther King.

dissymmetry
dissymmetry (di-sim′e-tre)

SYN: asymmetry. [dis- + symmetry]

distad
distad (dis′tad)

Toward the periphery; in a distal direction.

distal
distal (dis′tal) [TA]

1. Situated away from the center of the body, or from the point of origin; specifically applied to the extremity or distant part of a limb or organ. 2. In dentistry, away from the median sagittal plane of the face, following the curvature of the dental arch. SYN: distalis [TA] . [L. distalis]

distalis
distalis (dis-ta′lis) [TA]

SYN: distal.

distance
distance (dis′tans)

The measure of space between two objects. [L. distantia, fr. di-sto, to stand apart, be distant]
focal d. the d. from the center of a lens to its focus.
infinite d. the limit of distant vision, the rays entering the eyes from an object at that point being practically parallel. SYN: infinity.
interarch d. 1. the vertical d. between the maxillary and mandibular arches under conditions of vertical dimensions which must be specified; 2. the vertical d. between maxillary and mandibular ridges. SYN: interalveolar space, interridge d..
interocclusal d. 1. the vertical d. between the opposing occlusal surfaces, assuming rest relation unless otherwise designated; SYN: interocclusal rest space (1) . 2. SYN: freeway space.
interridge d. SYN: interarch d..
large interarch d. a large d. between the maxillary and mandibular arches; may also imply an excessive vertical dimension. SYN: open bite (1) .
pupillary d. the d. between the center of each pupil; the major reference points in measuring for fitting of spectacle frames and lenses.
reduced interarch d. an occluding vertical dimension which results in an excessive interocclusal d. when the mandible is in rest position, and in a reduced interridge d. when the teeth are in contact.
small interarch d. a small d. between the maxillary and mandibular arches. SYN: close bite.
sociometric d. some measurable degree of mutual or social perception, acceptance, and understanding; hypothetically, greater sociometric d. is associated with more inaccuracy in evaluating a relationship ( e.g., it is easier to understand and deal with a native than a foreigner).

distensibility
distensibility (dis-ten-si-bil′i-te)

The capability of being distended or stretched. [L. dis- tendo, to stretch apart]

distention
distention, distension (dis-ten′shun)

The act or state of being distended or stretched. SEE ALSO: dilation. [L. dis-tendo, to stretch apart]

distichiasis
distichiasis (dis′ti-ki′a-sis)

A congenital, abnormal, accessory row of eyelashes. [G. di- double, + stichos, row]

distill
distill (dis-til′)

To extract a substance by distillation.

distillate
distillate (dis′ti-lat)

The product of distillation.

distillation
distillation (dis-ti-la′shun)

Volatilization of a liquid by heat and subsequent condensation of the vapor; a means of separating the volatile from the nonvolatile, or the more volatile from the less volatile, part of a liquid mixture. [L. de-(di-)stillo, pp. -atus, to drop down]
destructive d. SYN: dry d..
dry d. submission of an organic substance to heat in a closed vessel so that oxygen is absent and combustion prevented, with the objective of effecting its decomposition with release of volatile constituents and the formation of new substances. SYN: destructive d..
fractional d. d. of a compound liquid at varying degrees of heat whereby the components of different boiling points are collected separately.
molecular d. d. in high vacuum, intended to make possible use of low temperatures to minimize damage to thermally labile molecules that would be decomposed by boiling at higher temperatures.

distobuccal
distobuccal (dis-to-buk′kal)

Relating to the distal and buccal surfaces of a tooth; denoting the angle formed by their junction.

distobucco-occlusal
distobucco-occlusal (dis′to-buk′o-o-kloo′sal)

Relating to the distal, buccal, and occlusal surfaces of a bicuspid or molar tooth; denoting especially the angle formed by the junction of these surfaces.

distobuccopulpal
distobuccopulpal (dis′to-buk′o-pul′pal)

Relating to the point (trihedral) angle formed by the junction of a distal, buccal, and pulpal wall of a cavity.

distocervical
distocervical (dis-to-ser′vi-kal)

Relating to the line angle formed by the junction of the distal and cervical (gingival) walls of a class V cavity.

distoclusal
distoclusal (dis-to-kloo′sal)

1. Relating to or characterized by distoclusion. 2. Denoting a compound cavity or restoration involving the distal and occlusal surfaces of a tooth. 3. Denoting the line angle formed by the distal and occlusal walls of a class V cavity. SYN: disto-occlusal.

distoclusion
distoclusion (dis-to-kloo′zhun)

A malocclusion in which the mandibular arch articulates with the maxillary arch in a position distal to normal; in Angle classification, a Class II malocclusion. SYN: distal occlusion (2) .

distogingival
distogingival (dis-to-jin′ji-val)

Relating to the junction of the distal surface with the gingival line of a tooth.

distoincisal
distoincisal (dis′to-in-si′zal)

Relating to the line (dihedral) angle formed by the junction of the distal and incisal walls of a class V cavity in an anterior tooth.

distolabial
distolabial (dis-to-la′be-al)

Relating to the distal and labial surfaces of a tooth; denoting the angle formed by their junction.

distolabiopulpal
distolabiopulpal (dis′to-la′be-o-pul′pal)

Relating to the point (trihedral) angle formed by the junction of distal, labial and pulpal walls of the incisal part of a class IV (mesioincisal) cavity.

distolingual
distolingual (dis-to-ling′gwal)

Relating to the distal and lingual surfaces of a tooth; denoting the angle formed by their junction.

distolinguo-occlusal
distolinguo-occlusal (dis′to-ling′gwo-o-kloo′zal)

Relating to the distal, lingual, and occlusal surfaces of a bicuspid or molar tooth; denoting especially the angle formed by the junction of these surfaces.

Distoma
Distoma (dis′to-ma)

Obsolete term for various digenetic flukes, now referred to other genera; e.g., Fasciola, Fasciolopsis, Paragonimus, Opisthorchis, Clonorchis, Dicrocoelium, Heterophyes, and Schistosoma. SYN: Distomum. [G. di-, two, + stoma, mouth]

distomiasis
distomiasis, distomatosis (dis′to-mi′a-sis, -ma-to′sis)

Presence in any of the organs or tissues of digenetic flukes formerly classified as Distoma or Distomum; in general, infection by any parasitic trematode or fluke.
hemic d. SYN: schistosomiasis.
pulmonary d. SYN: paragonimiasis.

distomolar
distomolar (dis-to-mo′lar)

A supernumerary tooth located in the region posterior to the third molar tooth.

Distomum
Distomum (dis′to-mum)

SYN: Distoma.

disto-occlusal
disto-occlusal (dis′to-o-kloo′sal)

SYN: distoclusal.

disto-occlusion
disto-occlusion (dis′to-o-kloo′zhun)

SYN: distal occlusion (1) .

distoplacement
distoplacement (dis′to-plas-ment)

SYN: distoversion.

distopulpal
distopulpal (dis-to-pul′pal)

Relating to the line (dihedral) angle formed by the junction of the distal and pulpal walls of a cavity.

distortion
distortion (dis-tor′shun)

1. In psychiatry, a defense mechanism that helps to repress or disguise unacceptable thoughts. 2. In dental impressions, the permanent deformation of the impression material after the registration of an imprint. 3. A twisting out of normal shape or form. 4. In ophthalmology, unequal magnification over a field of view. [L. distortio, fr. dis-torqueo, to wrench apart]
barrel d. irregular image produced when peripheral magnification is greater than axial magnification. See Petzval surface.
parataxic d. an attitude toward another person based on a distorted evaluation, usually because of too close an identification of that person with emotionally significant figures in the patient's past life.
pincushion d. irregular image produced when axial magnification is greater than peripheral magnification. See Petzval surface.

distoversion
distoversion (dis′to-ver-zhun)

Malposition of a tooth distal to normal, in a posterior direction following the curvature of the dental arch. SYN: distoplacement.

distractibility
distractibility (dis-trak-ti-bil′i-te)

A disorder of attention in which the mind is easily diverted by inconsequential occurrences; seen in mania and attention deficit disorder.

distraction
distraction (dis-trak′shun)

1. Difficulty or impossibility of concentration or fixation of the mind. 2. A force applied to a body part to separate bony fragments or joint surfaces. [L. dis-traho, pp. -tractus, to pull in different directions]

distress
distress (dis-tres′)

Mental or physical suffering or anguish. [L. distringo, to draw asunder]
fetal d. SYN: nonreassuring fetal status.

distribution
distribution (dis-tri-bu′shun)

1. The passage of the branches of arteries or nerves to the tissues and organs. 2. The area in which the branches of an artery or a nerve terminate, or the area supplied by such an artery or nerve. 3. The relative numbers of individuals in each of various categories or populations such as in different age, sex, or occupational samples. See frequency d.. 4. Partition. 5. The pattern of occurrence of a substance within or between cells, tissues, organisms, or taxa. [L. distribuo, pp. -tributus, to distribute, fr. tribus, a tribe]
Bernoulli d. the probability d. associated with two mutually exclusive and exhaustive outcomes, e.g., death or survival.
binomial d. 1. a probability d. associated with two mutually exclusive outcomes, e.g., presence or absence of a clinical sign. 2. the possible array of the number of successes in the outcomes from a fixed number, n, of independent Bernoulli trials; the probabilities associated with each constitute a binomial process of order n.
chi-square d. (ki) a variable is said to have a chi-square d. with K degrees of freedom if it is distributed like the sum of the squares of K independent random variables, each of which has a normal (gaussian) d. with mean zero and variance one. The chi square d. is the basis for many variations of the chi-square(d) test, perhaps the most widely used test for statistical significance in biology and medicine.
countercurrent d. a method of separation of two or more substances by repeated d. between two immiscible liquid phases that move past each other in opposite directions; a form of liquid-liquid chromatography.
dermatomal d. SYN: dermatome (3) .
epidemiological d. histogram.
exponential d. the time until failure of a process at constant hazard.
f d. the d. of the ratio of two independent quantities each of which is distributed like a variance in normally distributed samples. So named in honor of the English statistician and geneticist R.A. Fisher.
frequency d. a statistical description of raw data in terms of the number or frequency of items characterized by each of a series or range of values of a continuous variable.
gaussian d. SYN: normal d..
lognormal d. if a variable y is such that x = log y, it is said to have a lognormal d.; this is a skew d..
multinomial d. probability d. associated with the classification of each of a sample of individuals into one of several mutually exclusive and exhaustive categories.
normal d. a specific bell-shaped frequency d. commonly assumed by statisticians to represent the infinite population of measurements from which a sample has been drawn; characterized by two parameters, the mean (x) and the standard deviation (σ), in the equation: SYN: gaussian curve, gaussian d..
Poisson d. 1. a discontinuous d. important in statistical work and defined by the equation p (x) = e ^-μμ^x/ x!, where e is the base of natural logarithms, x is the sequence of integers, μ is the mean, and x! represents the factorial of x. 2. a d. function used to describe the occurrence of rare events, or the sampling d. of isolated counts in a continuum of time or space.
skew d. an asymmetrical frequency d.; in biology and medicine it is usually a lognormal d..
t d. the d. of the quotient of independent random variables, the numerator of which is a standardized normal variate and the denominator the positive square root of the quotient of a chi-square distributed variate and its number of degrees of freedom.

districhiasis
districhiasis (dis-tri-ki′a-sis)

Growth of two hairs in a single follicle. [G. dis, double, + thrix (trich-), hair]

distrix
distrix (dis′triks)

Splitting of the hairs at their ends. [G. dis, twice, + thrix, hair]

distropin
distropin

SYN: dystrophin.

disturbance
disturbance (dis-ter′bans)

Deviation from, interruption of, or interference with a normal state.
emotional d., mental d. mental illness, behavior disorder.

disulfamide
disulfamide (di-sul′fa-mid)

A diuretic.

disulfate
disulfate (di-sul′fat)

A molecule containing two sulfates.

disulfide
disulfide (di-sul′fid)

1. A molecule containing two atoms of sulfur to one of the reference element, e.g., CS₂, carbon d.. 2. A compound containing the –S–S– group, e.g., cystine.
asymmetric d. SYN: mixed d..
mixed d. d. which is not symmetric on both sides of the &cbond;S&cbond;S&cbond; linkage; e.g., the d. formed between coenzyme A and glutathione or between cysteine and coenzyme A or glutathione. SYN: asymmetric d..
symmetric d. d. that is symmetric on both sides of the &cbond;S&cbond;S&cbond; linkage; i.e., d. formed from identical thiol-containing compounds; e.g., cystine, glutathione d..

disulfiram
disulfiram (di-sul′fi-ram)

An antioxidant that interferes with the normal metabolic degradation of alcohol in the body, resulting in increased acetaldehyde concentrations in blood and tissues. Used in the treatment of chronic alcoholism; when a small quantity of alcohol is consumed an unpleasant reaction results. Also used as a chelator in copper and nickel poisoning. SYN: tetraethylthiuram disulfide.

DIT
DIT

Abbreviation for diiodotyrosine.

diterpenes
diterpenes (di-ter′penz)

Hydrocarbons or their derivatives containing four isoprene units, hence containing 20 carbon atoms and four branched methyl groups; e.g., vitamin A, retinene, aconitine.

dithiazanine iodide
dithiazanine iodide (di-thi-az′a-nen)

A broad spectrum anthelmintic, effective against Strongyloides.

dithiothreitol
dithiothreitol (di-the′o-thre-tol)

A donor of thiol groups used in biochemical and pharmacological studies. SYN: Cleland reagent.

dithranol
dithranol (dith′ra-nol)

SYN: anthralin.

Dittrich
Dittrich

Franz, German pathologist, 1815–1859. See D. plugs, under plug, D. stenosis.

diuresis
diuresis (di-u-re′sis)

Excretion of urine; commonly denotes production of unusually large volumes of urine. [G. dia, throughout, completely, + ouresis, urination]
alcohol d. d. following the ingestion of alcoholic beverages; due, in part, to inhibition of the output of antidiuretic hormone by the neurohypophysis.
osmotic d. d. due to a high concentration of osmotically active substances in the renal tubules ( e.g., urea, sodium sulfate), which limit the reabsorption of water.
water d. d. following the drinking of water; due to reduced secretion of the antidiuretic hormone of the neurohypophysis in response to the lowered osmotic pressure of the blood.

diuretic
diuretic (di-u-ret′ik)

1. Promoting the excretion of urine. 2. An agent that increases the amount of urine excreted.
cardiac d. a d. that acts by increasing function of the heart, and thereby improves renal perfusion.
direct d. a d. whose primary effect is on renal tubular function.
indirect d. a d. that acts by increasing cardiac function or by increasing the state of hydration.
loop d. a class of d. agents ( e.g., furosemide, ethacrynic acid) that act by inhibiting reabsorption of sodium and chloride, not only in the proximal and distal tubules but also in Henle loop.
mercurial diuretics d. drugs containing organic mercury ( e.g., Mercuhydrin) that promote substantial salt and water loss through the kidney. Among the first potent d. agents used in congestive heart failure, but now obsolescent.
osmotic diuretics drugs, such as mannitol, which by their osmotic effects retain water during urine formation and thus dilute electrolytes in the urine, making resorption less efficient; they promote the elimination of water and electrolytes in the urine.
potassium sparing diuretics d. agents that, unlike most diuretics, retain potassium; examples are triamterene and amiloride. Often used together with diuretics that promote the loss of both sodium and potassium. Used in hypertension and in congestive heart failure.

diurnal
diurnal (di-er′nal)

1. Pertaining to the daylight hours; opposite of nocturnal. 2. Repeating once each 24 hours, e.g., a d. variation or a d. rhythm. Cf.:circadian. [L. diurnus, of the day]

divalence
divalence, divalency (di-va′lens, di-va′len-se)

SYN: bivalence.

divalent
divalent (di-va′lent, div′a-)

SYN: bivalent (1) .

divalproex sodium
divalproex sodium (di-val′pro-eks)

Pentanoic acid, 2-propyl-, sodium salt (2:1); an anticonvulsant used in absence seizures and related seizure disorders. Derived from valproic acid.

divarication
divarication (di′var-i-ka′shun)

SYN: diastasis (1) . [L. divaricare, to spread asunder]

divergence
divergence (di-ver′jens)

1. A moving or spreading apart or in different directions. 2. The spreading of branches of the neuron to form synapses with several other neurons. [L. di-, apart, + vergo, to incline]

divergent
divergent (di-ver′jent)

Moving in different directions; radiating.

diverticula
diverticula (di-ver-tik′u-la)

Plural of diverticulum.

diverticular
diverticular (di-ver-tik′u-lar)

Relating to a diverticulum.

diverticulectomy
diverticulectomy (di′ver-tik-u-lek′to-me)

Excision of a diverticulum.

diverticulitis
diverticulitis (di′ver-tik-u-li′tis)

Inflammation of a diverticulum, especially of the small pockets in the wall of the colon which fill with stagnant fecal material and become inflamed; rarely, they may cause obstruction, perforation, or bleeding.

diverticuloma
diverticuloma (di′ver-tik-u-lo′ma)

Development of a granulomatous mass in the wall of the colon. [diverticulum + G. -oma, tumor]

diverticulopexy
diverticulopexy (di-ver-tik′u-lo-pek-se)

An operation to obliterate a diverticulum without resecting it, usually by securing the tip to a nearby structure so the diverticulum no longer fills. [diverticulum + G. pexis, fixation]

diverticulosis
diverticulosis (di′ver-tik-u-lo′sis)

Presence of a number of diverticula of the intestine, common in middle age; the lesions are acquired pulsion diverticula.

diverticulum
diverticulum, pl .diverticula (di-ver-tik′u-lum, u-la) [tA]

A pouch or sac opening from a tubular or saccular organ, such as the gut or bladder. [L. deverticulum (or di-), a by-road, fr. de-verto, to turn aside]
allantoenteric d. SYN: allantoic d..
allantoic d. an endoderm-lined outpouching of the hindgut representing the primordium of the allantois; in most amniotes, it grows into the extraembryonic celom; in humans, the distal part of the allantoic lumen is rudimentary, not extending beyond the body stalk. SYN: allantoenteric d..
diverticula ampullae ductus deferentis [TA] SYN: diverticula of ampulla of ductus deferens.
caliceal d. a congenital or acquired distention of a kidney calix that renders it susceptible to calculus formation. SEE ALSO: Fraley syndrome.
cervical d. a d. in the neck derived from retention of part of one of the pharyngeal pouches (endodermal) or branchial grooves (ectodermal) of the embryo.
diverticula of colon diverticula, which are herniations of mucosa and submucosa through or between fibers of the major muscle layer (muscularis propria) of the colon. Usually multiple, it occurs in 50% of western populations above the age of 70, but is much less common in other populations. Can cause bleeding and episodes of severe inflammation. SYN: colonic diverticula.
colonic diverticula SYN: diverticula of colon.
diverticula of ampulla of ductus deferens [TA] the irregular sacculations of the ampullary part of the ductus deferens near its termination in the ejaculatory duct. SYN: diverticula ampullae ductus deferentis [TA] .
duodenal d. a d. of the duodenum, often of large size, that is occasionally found projecting from the duodenum near the duodenal papilla.
epiphrenic d. a d. which originates just above the cardioesophageal junction and usually protrudes to the right side of the lower mediastinum.
false d. a d. of the intestine that passes through a defect in the muscular wall of the gut and thus does not include a layer of muscle in its wall.
Heister d. bulb of jugular vein.
hypopharyngeal d. SYN: pharyngoesophageal d..
Kommerell d. not a true d., but a bulblike swelling at the origin of the left subclavian artery due to a remnant of the left fourth aortic arch; associated vascular ring compression syndromes involve persistent right aortic arch; the left subclavian artery may pass behind the esophagus; the d. may be large enough to compress the trachea and esophagus even after the vascular ring has been divided and may need to be resected or affixed to the chest wall or vertebral fascia.
laryngotracheal d. a d. from the floor of the caudal end of the pharynx which gives rise to the epithelium and glands of the larynx, trachea, bronchi, and lungs. Once this d. separates from the foregut, it is referred to as a tube.
Meckel d. the remains of the yolk stalk of the embryo, which, when persisting abnormally as a blind sac or pouch in the adult, is located on the ileum a short distance above the cecum; it may be attached to the umbilicus and, if the lining includes gastric mucosa, peptic ulceration and bleeding may result.
metanephric d. an outgrowth from the caudal portion of the mesonephric duct on either side, which grows cephalodorsally to make contact with the masses of metanephrogenous tissue (nephric blastemas) and give rise to the epithelial lining of the ureter and of the pelvis and the collecting ducts of the kidney.
Nuck d. SYN: processus vaginalis of peritoneum.
pancreatic diverticula the ventral and dorsal endodermal buds from the embryonic foregut that constitute the primordia of the parenchyma of the pancreas.
Pertik d. an abnormally deep recessus pharyngeus.
pharyngoesophageal d. most common d. of the esophagus; a pulsion d. developing between the inferior pharyngeal constrictor and the cricopharyngeus muscle. SYN: hypopharyngeal d., Zenker d..
pituitary d. a tubular outgrowth of ectoderm from the stomodeum of the embryo; it grows dorsad toward the infundibular process of the diencephalon, around which it forms a cuplike mass, giving rise to the pars distalis and pars juxtaneuralis of the hypophysis. SYN: craniopharyngeal canal, hypophyseal pouch, Rathke d., Rathke pocket, Rathke pouch.
pulsion d. a d. formed by pressure from within, frequently causing herniation of mucosa through the muscularis.
Rathke d. SYN: pituitary d..
thyroid d., thyroglossal d. the endodermal bud from the floor of the embryonic pharynx; the primordium of the parenchyma of the thyroid gland.
tracheobronchial d. the endodermal lung primordium which will give rise to the epithelial lining of the respiratory tract. SYN: lung bud.
traction d. a d. formed by the pulling force of contracting bands of adhesion, occurring mainly in the distal esophagus, from tuberculous hilar or mediastinal lymphadenitis.
true d. a term denoting a d. that includes all the layers of the wall from which it protrudes.
urethral d. a saclike outpouching of the urethral wall, either from a congenital defect or, more commonly, as a result of chronic penetrating inflammation.
ventricular d. a congenital outpouching of the right or left ventricle.
vesical d. a d. of the bladder wall; may be either true or false type.
Zenker d. SYN: pharyngoesophageal d..

divicine
divicine (di′vis-en)

A base with alkaloidal properties present in Lathyrus sativus that is responsible, in part at least, for the latter's poisonous action. See lathyrism.

divisio
divisio

SYN: division.
divisiones anteriores plexus brachialis [TA] SYN: anterior divisions of (trunks of) brachial plexus, under division.
d. autonomica systematis nervosi peripherici [TA] SYN: autonomic division of nervous system.
d. lateralis dextra hepatis [TA] SYN: right lateral division of liver.
d. lateralis sinistra left lobe of liver.
d. lateralis sinistra hepatis [TA] SYN: left lateral division of liver.
d. medialis dextra hepatis [TA] SYN: right medial division of liver.
d. medialis sinistra hepatis [TA] SYN: left medial division of liver.
divisiones posteriores plexus brachialis [TA] SYN: posterior divisions of (trunks of) brachial plexus, under division.

division
division (di-vizh′un)

A separating into two or more parts. SEE ALSO: ramus. SYN: divisio.
anterior primary d. SYN: anterior ramus of spinal nerve.
anterior divisions of (trunks of) brachial plexus [TA] portion of the superior, middle, and inferior trunks of the brachial plexus that are destined to serve the anterior or flexor compartments of the upper limb. SYN: divisiones anteriores plexus brachialis [TA] .
autonomic d. of nervous system [TA] that part of the nervous system which represents the motor innervation of smooth muscle, cardiac muscle, and gland cells. It consists of two physiologically and anatomically distinct, mutually antagonistic components: the sympathetic and parasympathetic parts. In both of these parts the pathway of innervation consists of a synaptic sequence of two motor neurons, one of which lies in the spinal cord or brainstem as the presynaptic (preganglionic) neuron, the thin but myelinated axon of which (presynaptic (preganglionic) or B fiber) emerges with an outgoing spinal or cranial nerve and synapses with one or more of the postsynaptic (postganglionic or, more strictly, ganglionic) neurons composing the autonomic ganglia; the unmyelinated postsynaptic fibers in turn innervate the smooth muscle, cardiac muscle, or gland cells. The presynaptic neurons of the sympathetic part lie in the intermediolateral cell column of the thoracic and upper two lumbar segments of the spinal gray matter; those of the parasympathetic part compose the visceral motor (visceral efferent) nuclei of the brainstem as well as the lateral column of the second to fourth sacral segments of the spinal cord. The ganglia of the sympathetic part are the paravertebral ganglia of the sympathetic trunk and the lumbar and sacral prevertebral or collateral ganglia; those of the parasympathetic part lie either near the organ to be innervated or as intramural ganglia within the organ itself except in the head, where there are four discrete parasympathetic ganglia (ciliary, otic, pterygopalatine, and submandibular). Impulse transmission from presynaptic to postsynaptic neuron is mediated by acetylcholine in both the sympathetic and parasympathetic parts; transmission from the postsynaptic fiber to the visceral effector tissues is classically said to be by acetylcholine in the parasympathetic part and by noradrenalin in the sympathetic part; recent evidence suggests the existence of further noncholinergic, nonadrenergic classes of postsynaptic fibers. SYN: divisio autonomica systematis nervosi peripherici [TA] , pars autonomica systematis nervosi peripherici [TA] , autonomic part of peripheral nervous system&star, autonomic nervous system, involuntary nervous system, systema nervosum autonomicum, vegetative nervous system, visceral motor system, visceral nervous system.
cleavage d. the rapid mitotic d. of the zygote with decrease in size of individual cells or blastomeres and the formation of a morula. SEE ALSO: cleavage (1) .
conjugate d. simultaneous d. of haploid nuclei, as in Basidiomycota.
craniosacral d. of autonomic nervous system SYN: parasympathetic part of autonomic d. of peripheral nervous system.
direct nuclear d. SYN: amitosis.
equatorial d. nuclear d. in which each chromosome divides equally.
indirect nuclear d. SYN: mitosis.
lateral d. of left liver left lobe of liver.
left lateral d. of liver [TA] in the surgical schema for subdividing the liver, the portion that lies to the left of the approximately vertical plane of the left hepatic vein and includes the left posterior and anterior lateral segments (hepatic segments II and III); it corresponds with the left anatomic lobe of the liver, and so is demarcated externally by the falciform ligament on the diaphragmatic surface and by the fissures for the ligamentum venosum and ligamentum teres on the viscera surface. SYN: divisio lateralis sinistra hepatis [TA] .
left medial d. of liver [TA] in the surgical schema for subdividing the liver, the portion that lies between the approximately vertical planes of the left and middle hepatic veins and includes the left medial segment (hepatic segment IV); on the diaphragmatic surface, it is approximately the left third of the anatomic right lobe of the liver; on the visceral surface, its inferior portion corresponds to the quadrate lobe. SYN: divisio medialis sinistra hepatis [TA] .
meiotic d. SYN: meiosis.
mitotic d. SYN: mitosis.
multiplicative d. reproduction by simultaneous d. of a mother cell into a number of daughter cells. If the process occurs without fertilization of the mother cell, or encystment, the daughter cells are called merozoites; if they develop within a cyst, and usually after fertilization, they are called sporozoites.
posterior primary d. SYN: posterior ramus of spinal nerve.
posterior divisions of (trunks of) brachial plexus [TA] portion of the superior, middle, and inferior trunks of the brachial plexus that are destined to serve the posterior or extensor compartments of the upper limb. SYN: divisiones posteriores plexus brachialis [TA] .
reduction d. reduction of chromosomes.
Remak nuclear d. SYN: amitosis.
right lateral d. of liver [TA] in the surgical schema for subdividing the liver, the portion that lies to the right of the approximately vertical plane of the right hepatic vein and includes the right anterior and posterior lateral segments (hepatic segments VI and VII); it is approximately the right third of the right anatomic lobe of the liver. SYN: divisio lateralis dextra hepatis [TA] .
right medial d. of liver [TA] in the surgical schema for subdividing the liver, the portion that lies between the approximately vertical planes of the right and middle hepatic veins and includes the right anterior and posterior medial segments (hepatic segments V and VIII); it is approximately the middle third of the anatomic right lobe of the liver. SYN: divisio medialis dextra hepatis [TA] .

div. in p. aeg.
div. in p. aeg.

Abbreviation for L. divide in partes aequales, divide into equal parts.

divulse
divulse (di-vuls′)

To tear away or apart. [L. divello, pp. di-vulsus, to pull apart]

divulsion
divulsion (di-vul′shun)

1. Removal of a part by tearing. 2. Forcible dilation of the walls of a cavity or canal.

divulsor
divulsor (di-vul′ser, -sor)

An instrument for forcible dilation of the urethra or other canal or cavity.

Dix
Dix

M.R., 20th century British otologist. See D.-Hallpike maneuver.

dixyrazine
dixyrazine (di-zir′a-zen)

A phenothiazine compound used as an antipsychotic.

dizygotic
dizygotic, dizygous (di′zi-got′ik, di-zi′gus)

Relating to twins derived from two separate zygotes, i.e., bearing the same genetic relationship as full sibs but sharing a common intrauterine environment. [G. di-, two, + zygotos, yoked together]

dizziness
dizziness (diz′i-nes)

Imprecise term commonly used to describe various symptoms such as faintness, giddiness, imbalance, lightheadedness, unsteadiness, or vertigo. SEE ALSO: vertigo. [A. S. dyzig, foolish]

djenkolic acid
djenkolic acid (jeng-kol′ik)

S,S′-Methylenebiscysteine;a sulfur-containing amino acid, resembling cystine but with a methylene bridge between the two sulfur atoms; very insoluble. [djenkol bean, bean in which first isolated]

dl- dl-

Prefix (in small capital letters) denoting a substance consisting of equal quantities of the two enantiomorphs, d and l; replaces the older dl- as a more exact definition of structure.

<SMCAP>dl</SMCAP>-narcotine
dl-narcotine (nar′ko-ten)

SYN: gnoscopine.

DM
DM

Abbreviation for adamsite; diabetes mellitus; diastolic murmur; dopamine.

DMA
DMA

Abbreviation for dimethoxyamphetamine.

DMARD
DMARD

Acronym for disease modifying antirheumatic drugs, under drug.

DMC
DMC

Abbreviation for p,p,′-dichlorodiphenyl methyl carbinol.

D.M.D.
D.M.D.

Abbreviation for Doctor of Dental Medicine.

dmf
dmf, DMF

Abbreviation for decayed, missing, and filled teeth. SEE ALSO: dmfs caries index.

dmfs
dmfs, DMFS

Abbreviation for decayed, missing, and filled surfaces. SEE ALSO: d. caries index.

DMPP
DMPP

Abbreviation for dimethylphenylpiperazinium.

DMSA
DMSA

See ^99mTc-dimercaptosuccinic acid.

DMSO
DMSO

Abbreviation for dimethyl sulfoxide.

DMT
DMT

Abbreviation for N,N-dimethyltryptamine.

DN
DN

Abbreviation for dibucaine number.

DNA
DNA

Abbreviation for deoxyribonucleic acid. For terms bearing this abbreviation, see subentries under deoxyribonucleic acid.

DNA diagnostics
DNA diagnostics

SYN: genetic testing. See DNA markers, familial screening, prenatal screening.

dnaG
dnaG

SYN: primase.

DNA markers
DNA markers

Segments of chromosomal DNA known to be linked with heritable traits or diseases. Although the markers themselves do not produce the conditions, they exist in concert with the genes responsible and are passed on with them. Certain markers, restriction fragment length polymorphisms, consist of segments of DNA that can be identified on autoradiographs (produced after digestion of the DNA by restriction enzymes and segregation of the resulting fragments through gel electrophoresis).

DNAse
DNAse, DNAase, DNase

Abbreviations for deoxyribonuclease.

DNP
DNP, Dnp

1. Abbreviation for 2,4-dinitrophenol. 2. Abbreviation for deoxyribonucleoprotein.

DNR
DNR

Abbreviation for “do not resuscitate.”

Dns
Dns, DNS

Abbreviations for dansyl.

D.O.
D.O.

Abbreviation for Doctor of Osteopathy.

DOA
DOA

Abbreviation for dead on arrival.

dobutamine
dobutamine (do-bu′ta-men)

A synthetic derivative of dopamine characterized by prominent inotropic but weak chronotropic and arrhythmogenic properties; a cardiotonic agent.

DOC
DOC

Abbreviation for deoxycorticosterone; deoxycholate.

d'Ocagne
d'Ocagne

Philbert M., French mathematician, 1862–1938. See d'Ocagne nomogram.

doctor
doctor (dok′ter)

1. A title conferred by a university on one who has followed a prescribed course of study, or given as a title of distinction; as d. of medicine, laws, philosophy, etc. 2. A physician, especially one upon whom has been conferred the degree of M.D. by a university or medical school. [L. a teacher, fr. doceo, pp. doctus, to teach]

doctrine
doctrine (dok′trin)

A particular system of principles taught or advocated. [L. doceo, to teach]
Arrhenius d. the theory of electrolytic dissociation (1887) that became the basis of our modern understanding of electrolytes: in an electrically conductive solution ( e.g., acid, base, or salt), free ions are present before electrolysis, and the proportion of molecules dissociated into ions can be calculated from measurements of electrical conductivity as well as of osmotic pressure. SYN: Arrhenius law.
humoral d. the ancient Greek theory of the four body humors (blood, yellow and black bile, and phlegm) that determined health and disease. The humors were associated with the four elements (air, fire, earth, and water), which in turn were paired with one of the qualities (hot, cold, dry, and moist). A proper and evenly balanced mixture of the humors characterized health of body and mind; an imperfect balance resulted in disease. Temperament of body or mind also was supposed to be determined, e.g., sanguine (blood), choleric (yellow bile), melancholic (black bile), or phlegmatic (phlegm). SYN: fluidism, humoralism, humorism.
Monro d. a d. that states that the cranial cavity is a closed rigid box and that therefore a change in the quantity of intracranial blood can occur only through the displacement of or replacement by cerebrospinal fluid. SYN: Monro-Kellie d..
Monro-Kellie d. SYN: Monro d..

docusate calcium
docusate calcium (dok′u-sat)

A surface-active agent used in the treatment of constipation as a nonlaxative fecal softener. SYN: dioctyl calcium sulfosuccinate.

docusate sodium
docusate sodium

A surface-active agent used as a dispersing agent in topically applied preparations. After oral administration it lowers the surface tension of the gastrointestinal tract and is used in the treatment of constipation as a wetting agent and stool softener. SYN: dioctyl sodium sulfosuccinate.

dodecane
dodecane (do′de-kan)

n-C₁₂H₂₆;a straight, unbranched, saturated hydrocarbon containing 12 carbon atoms; the 12th member of the alkane series that begins with methane.

dodecanoyl-CoA synthetase
dodecanoyl-CoA synthetase (do-dek′an-o-il-ko-asin′the-tas)

SYN: long-chain fatty acid-CoA ligase.

dodecarbonium chloride
dodecarbonium chloride (do-de-kar-bo′ne-um)

An antiseptic.

dodecyl
dodecyl (do′de-sil)

The radical of dodecane.
d. gallate an antioxidant.
d. sulfate sodium d. sulfate.

Döderlein
Döderlein

Albert, S.G., German obstetrician, 1860–1941. See D. bacillus.

Doerfler
Doerfler

Leo G., U.S. audiologist, *1919. See D.-Stewart test.

Dogiel
Dogiel

Jan von, Russian anatomist and physiologist, 1830–1905. See D. cells, under cell.

Dogiel
Dogiel

Alexander S., Russian histologist, 1852–1922. See D. corpuscle.

dogma
dogma

A theory or belief that is formally stated, defined, and thought to be true.
central d. the proposition that while genetic information is transferred from parent to offspring via DNA duplication, within the cell, genetic information is transferred from DNA to mRNA (transcription) and then to protein (translation); proposed by Francis Crick.

dogmatic dogmatic (dog-mat′ik)

See d. school. [G. dogmatikos, concerning opinions; d. iatroi, physicians who go by general principles; fr. dogma, an opinion]

dogmatist dogmatist (dog′ma-tist)

A follower of the dogmatic school.

Döhle
Döhle

Karl G.P., German histologist and pathologist, 1855–1928. See D. bodies, under body, D. inclusions, under inclusion.

Doisy
Doisy

Edward A., U.S. biochemist and Nobel laureate, 1893–1986. See Allen-D. test, Allen-D. unit.

dol
dol (dol)

A unit measure of pain. [L. dolor, pain]

dolicho- dolicho-

Long. [G. dolichos]

dolichocephalic
dolichocephalic, dolichocephalous (dol-i-ko-se-fal′ik, -sef′a-lus)

Having a disproportionately long head; denoting a skull with a cephalic index below 75. SYN: dolichocranial. [dolicho- + G. kephale, head]

dolichocephaly
dolichocephaly, dolichocephalism (dol-i-ko-sef′a-le, sef′a-lizm)

The condition of being dolichocephalic.

dolichocolon
dolichocolon (dol-i-ko-ko′lon)

A colon of abnormal length. [dolicho- + G. kolon, colon]

dolichocranial
dolichocranial (dol-i-ko-kra′ne-al)

SYN: dolichocephalic.

dolichofacial
dolichofacial (dol-i-ko-fa′shal)

SYN: dolichoprosopic.

dolichol
dolichol (dol′i-kol)

Polyisoprenes in which the terminal member is saturated and oxidized to an alcohol, usually phosphorylated and often glycosylated; found in endoplasmic reticulum, but not in mitochondrial or plasma membranes; urinary levels are elevated in disorders exhibiting abnormal skin, rectal, or brain profiles in electron microscopy of biopsies.
d. phosphate an intermediate in the glycosylation of proteins and lipids; contains 11–24 isoprene units; a product of the isoprenylation pathway; participates in the formation of glycosylphosphatidylinositol anchors of proteins in biomembranes.

dolichopellic
dolichopellic, dolichopelvic (dol-i-ko-pel′ik, -pel′vik)

Having a disproportionately long pelvis; denoting a pelvis with a pelvic index above 95. [dolicho- + G. pellis, bowl (pelvis)]

dolichoprosopic
dolichoprosopic, dolichoprosopous (dol-i-ko-pros-o′pik, -ko-pros′o-pus)

Having a disproportionately long face. SYN: dolichofacial. [dolicho- + G. prosopikos, facial]

dolichostenomelia
dolichostenomelia (dol′i-ko-sten′o-me′le-a)

Narrow body habitus which, like arachnodactyly, is a common feature of several kinds of hereditary disorders of connective tissue. [dolicho- + G. stenos, narrow, + melos, limb]

dolichouranic
dolichouranic, dolichuranic (dol′i-ko-u-ran′ik, dol-ik-u-)

Having a long palate, with a palatal index below 110. [dolicho- + G. ouranos, vault of the palate]

Doll
Doll

Richard, British epidemiologist, *1912. See Armitage-D. model.

dolor
dolor (do′lor)

Pain, as one of the four signs of inflammation (d., calor, rubor, tumor) enunciated by Celsus. [L.]
d. capitis headache, especially due to changes in the scalp or bones rather than in the intracranial structures.

dolorific
dolorific (do-lor-if′ik)

Pain-producing.

dolorimetry
dolorimetry (do-lo-rim′e-tre)

The measurement of pain. [L. dolor, pain, + G. metron, measure]

dolorology
dolorology (do-lor-ol′o-je)

The study and treatment of pain. [L. dolor, pain, + G. logos, study]

DOM
DOM

Abbreviation for 2,5-dimethoxy-4-methylamphetamine.

domain
domain (do-man′)

1. Homologous unit of approximately 110–120 amino acids, groups of which make up the light and heavy chains of the immunoglobulin molecule; each serves a specific function. The light chain has two domains, one in the variable region and one in the constant region of the chain; the heavy chain has four to five domains, depending upon the class of immunoglobulin, one in the variable region and the remaining ones in the constant region. 2. A region of a protein having some distinctive physical feature or role. 3. An independently folded, globular structure composed of one section of a polypeptide chain. A d. may interact with another d.; it may be associated with a particular function. Domains can vary in size. [Fr. domaine, fr. L. dominium, property, dominion]
dinucleotide d. SYN: dinucleotide fold.

Dombrock blood group
Dombrock blood group

See Blood Groups appendix.

dome
dome

d. of pleura cervical pleura.

domestic violence
domestic violence

Intentionally inflicted injury perpetrated by and on family member(s); varieties include spouse abuse, child abuse, and sexual abuse, including incest. Various kinds of abuse, such as sexual abuse, also happen outside the family unit. The American Medical Association, like similar organizations in other countries, has issued advisory notices to physicians on the detection and treatment of d..

domiciliated
domiciliated (do-mi-sil′e-at-ed)

A state of close association of an organism within human abodes or activities, such that partial domestication results, leading to the organism's dependence on continued association with the human environment; this frequently results in the d. organism becoming a noxious pest, a vector, or an intermediate host of human disease. [L. domicilium, a dwelling]

dominance
dominance (dom′i-nans)

The state of being dominant.
cerebral d. the fact that one hemisphere is dominant over the other and will exercise greater influence over certain functions; the left cerebral hemisphere is usually dominant in the control of speech, language and analytical processing, and mathematics, while the right hemisphere (usually nondominant) processes spatial concepts and language as related to certain types of visual images; handedness (right-handed people have left cerebral d.) is considered a general example of cerebral d..
false d. SYN: quasidominance.
genetic d. denoting a pattern of inheritance of an autosomal mendelian trait due to a gene that always manifests itself phenotypically; generally, the phenotype in the homozygote is more severe than in the heterozygote, but details depend on what criterion of phenotyping is used.
d. of traits an expression of the apparent physiologic relationship existing between two or more genes that may occupy the same chromosomal locus (alleles). At a specific locus there are three possible combinations of two allelic genes, A and a: two homozygous (AA and aa) and one heterozygous (Aa). If a heterozygous individual presents only the hereditary characteristic determined by gene A, but not a, A is said to be dominant and a recessive; in this case, AA and Aa, although genotypically distinct, should be phenotypically indistinguishable. If AA, Aa, and aa are distinguishable, each from the others, A and a are codominant.

dominant
dominant (dom′i-nant)

1. Ruling or controlling. 2. In genetics, denoting an allele possessed by one of the parents of a hybrid which is expressed in the latter to the exclusion of a contrasting allele (the recessive) from the other parent. [L. dominans, pres. p. of dominor, to rule, fr. dominus, lord, master, fr. domus, house]

domiodol
domiodol (do-me′o-dol)

An organic form of iodine complexed with glycerol; used as a mucolytic/expectorant.

domiphen bromide
domiphen bromide (do′mi-fen)

An antiseptic.

domperidone
domperidone (dom-per′i-don)

A dopamine antagonist (like chlorpromazine) with antiemetic properties.

Donath
Donath

Julius, German physician, 1870–1950. See D.-Landsteiner phenomenon, D.-Landsteiner cold autoantibody, Landsteiner-D. test.

Donders
Donders

Franz C., Dutch ophthalmologist, 1818–1889. See D. law, D. pressure, space of D..

Don Juan
Don Juan (don wan)

In psychiatry, a term used to denote males with compulsive sexual or romantic overactivity, usually with a succession of female partners. [legendary Spanish nobleman]

Don Juanism
Don Juanism (don wan′izm)

See Don Juan.

Donnan
Donnan

Frederick G., English physical chemist, 1870–1956. See D. equilibrium, Gibbs-D. equilibrium.

Donné
Donné

Alfred, French physician, 1801–1878. See Donné corpuscle.

Donohue
Donohue

William L., Canadian pediatric pathologist, 1906–1984. See D. disease.

donor
donor (do′ner)

1. An individual from whom blood, tissue, or an organ is taken for transplantation. 2. A compound that will transfer an atom or a radical to an acceptor; e.g., methionine is a methyl d.; glutathione is a glutamyl d.. 3. An atom that readily yields electrons to an acceptor; e.g., nitrogen, which will donate both electrons to a shared pool in forming a coordinate bond. [L. dono, pp. donatus, to donate, to give]
hydrogen d. a metabolite from which hydrogen is removed (by a dehydrogenase system) and transferred by a hydrogen carrier to another metabolite, which is thus reduced.
universal d. in blood grouping, a person belonging to group O; i.e., one whose erythrocytes do not contain either agglutinogen A or B and are, therefore, not agglutinated by plasma containing either of the ordinary isoagglutinins.

Donovan
Donovan

Charles, Irish surgeon, 1863–1951. See D. bodies, under body, Leishman-D. body.

Doose
Doose

H., 20th century German pediatrician and epileptologist. See D. syndrome.

dopa
dopa, DOPA, Dopa (do′pa)

An intermediate in the catabolism of l-phenylalanine and l-tyrosine, and in the biosynthesis of norepinephrine, epinephrine, and melanin; the l form, levodopa, is biologically active. See d. reaction. SYN: 3,4-dihydroxyphenylalanine.
alpha methyl d. SYN: methyldopa.
d. decarboxylase SYN: aromatic d-amino acid decarboxylase.
decarboxylated d. SYN: dopamine.
d. oxidase provisional name given the enzyme(s) catalyzing the formation of melanins from d.; it now appears that the copper-containing monophenol monooxygenases and/or catechol oxidases are responsible for the oxidation of l-tyrosine to d. and d. quinone.
d. quinone an oxidation product of d. and an intermediate in the formation of melanin from tyrosine.

dopamine
dopamine (DM) (do′pa-men)

An intermediate in tyrosine metabolism and precursor of norepinephrine and epinephrine; it accounts for 90% of the catecholamines; its presence in the central nervous system and localization in the basal ganglia (caudate and lentiform nuclei) suggest that d. may have other functions. Depletion of d. produces Parkinson disease. SYN: 3-hydroxytyramine, decarboxylated dopa.
d. hydrochloride a biogenic amine and neural transmitter substance, used as a vasopressor agent for treatment of shock.

dopamine β-hydroxylase
dopamine β-hydroxylase

SYN: dopamine β-monooxygenase.

dopamine β-monooxygenase
dopamine β-monooxygenase

A copper-containing enzyme catalyzing oxidation of ascorbate and 3,4-dihydroxyphenylethylamine simultaneously by O₂ to yield norepinephrine, dehydroascorbate, and water; a crucial step in catecholamine metabolism. The enzyme is stimulated by fumarate. SYN: dopamine β-hydroxylase.

dopaminergic
dopaminergic (do′pa-min-er′jik)

Relating to nerve cells or fibers that employ dopamine as their neurotransmitter. [dopamine + G. ergon, work]

dope
dope (dop)

1. Any drug, either stimulating or depressing, administered for its temporary effect, or taken habitually or addictively. 2. To administer or take such a drug. [Dutch, doop, sauce]

doping
doping (dop′ing)

The administration of foreign substances to an individual; often used in reference to athletes who try to stimulate physical and psychological strength.

Doppler
Doppler

Johann Christian, Austrian mathematician and physicist, 1803–1853. See D. echocardiography, D. effect, D. phenomenon, D. shift, D. ultrasonography.

Doppler
Doppler

A diagnostic instrument that emits an ultrasonic beam into the body; the ultrasound reflected from moving structures changes its frequency (D. effect). Of diagnostic value in peripheral vascular and cardiac disease.

doraphobia
doraphobia (do-ra-fo′be-a)

Morbid fear of touching the skin or fur of animals. [G. dora, hide, skin, + phobos, fear]

Dorello
Dorello

P., Italian anatomist, *1872. See D. canal.

Dorendorf
Dorendorf

H., German physician, *1866. See D. sign.

Dorfman
Dorfman

Maurice L., 20th century Israeli dermatologist. See D.-Chanarin syndrome.

Döring
Döring

G., 20th century German neurologist. See Pette-D. disease.

dornase
dornase (dor′nas)

Obsolete contraction of deoxyribonuclease. SEE ALSO: streptodornase.
pancreatic d. a stabilized deoxyribonuclease preparation from beef pancreas; used by inhalation in the form of aerosols to reduce thick mucopurulent secretions in certain bronchopulmonary infections.

Dorno
Dorno

Carl, Swiss climatologist, 1865–1942.

doromania
doromania (do-ro-ma′ne-a)

An abnormal desire to give presents. [G. doron, gift, + mania, insanity]

dorsa
dorsa (dor′sa)

Plural of dorsum.

dorsabdominal
dorsabdominal (dor-sab-dom′i-nal)

Relating to the back and the abdomen.

dorsad
dorsad (dor′sad)

Toward or in the direction of the back. [L. dorsum, back, + ad, to]

dorsal
dorsal (dor′sal) [TA]

1. Pertaining to the back or any dorsum. SYN: tergal. 2. SYN: posterior (2) . 3. In veterinary anatomy, pertaining to the back or upper surface of an animal. Often used to indicate the position of one structure relative to another; i.e., nearer the back surface of the body. 4. Old term meaning thoracic, in a limited sense; e.g., d. vertebrae. [Mediev. L. dorsalis, fr. dorsum, back]

dorsalis
dorsalis (dor-sa′lis) [TA]

SYN: posterior (2) . [L.]

Dorset
Dorset

Marion, U.S. bacteriologist, 1872–1935. See D. culture egg medium.

dorsiduct
dorsiduct (dor′si-dukt)

To draw backward or toward the back. [L. dorsum, back, + duco, pp. ductus, to draw]

dorsiflexion
dorsiflexion (dor-si-flek′shun)

Upward movement (extension) of the foot or toes or of the hand or fingers.

dorsiscapular
dorsiscapular (dor′si-skap′u-lar)

Relating to the dorsal surface of the scapula.

dorsispinal
dorsispinal (dor′si-spi′nal)

Relating to the vertebral column, especially to its dorsal aspect.

dorsocephalad
dorsocephalad (dor′so-sef′a-lad)

Toward the occiput, or back of the head. [L. dorsum, back, + G. kephale, head, + L. ad, to]

dorsolateral
dorsolateral (dor-so-lat′er-al)

Relating to the back and the side.

dorsolumbar
dorsolumbar (dor-so-lum′bar)

Referring to the back in the region of the lower thoracic and upper lumbar vertebrae.

dorsoventrad
dorsoventrad (dor-so-ven′trad)

In a direction from the dorsal to the ventral aspect.

dorsum
dorsum, gen. dorsi, pl .dorsa (dor′sum, -si, -sa) [TA]

1. The back of the body. 2. The upper or posterior surface, or the back, of any part. SYN: tergum. [L. back]
d. ephippii SYN: d. sellae.
d. of foot [TA] the back, or upper surface, of the foot. SYN: d. pedis [TA] .
d. of hand [TA] the back of the hand; surface of hand opposite the palm.
d. linguae [TA] SYN: d. of tongue.
d. manus [TA] SYN: d. of hand.
d. nasi [TA] SYN: d. of nose.
d. of nose [TA] the external ridge of the nose, looking forward and upward. SYN: d. nasi [TA] .
d. pedis [TA] SYN: d. of foot.
d. of penis [TA] the aspect of the penis opposite to that of the urethra. SYN: d. penis [TA] .
d. penis [TA] SYN: d. of penis.
d. scapulae the posterior surface of the scapula.
d. sellae [TA] a square portion of bone on the body of the sphenoid posterior to the sella turcica or hypophysial fossa. SYN: d. ephippii.
d. of tongue [TA] the back of the tongue; the upper surface of the tongue divided by the sulcus terminalis into an anterior two-thirds, the pars presulcalis (presulcal part), and a posterior one-third, the pars postsulcalis (postsulcal part). SYN: d. linguae [TA] .

dosage
dosage (do′sij)

1. The giving of medicine or other therapeutic agent in prescribed amounts. 2. The determination of the proper dose of a remedy. Cf.:dose. 3. In nuclear medicine, quantity of radiopharmaceutical given.

dose
dose (dos)

1. The quantity of a drug or other remedy to be taken or applied all at one time or in fractional amounts within a given period. Cf.:dosage (2) . 2. In nuclear medicine, amount of energy absorbed per unit mass of irradiated material (absorbed d.). SEE ALSO: dosage (3) . [G. dosis, a giving]
absorbed d. the amount of energy absorbed per unit mass of irradiated material at the target site; in radiation therapy, the former unit for absorbed d. is the rad (100 ergs/g); the current (SI) unit is the gray (1 J/kg or 100 rad).
air d. SYN: exposure d..
bone marrow d. the cumulative d. to the blood-forming organ from therapeutic or nuclear fallout irradiation; the presumed leukemogenic d..
booster d. a d. given at some time after an initial d. to enhance the effect, said usually of antigens for the production of antibodies.
cumulative d. the total d. resulting from repeated exposures to radiation or chemotherapy of the same part of the body or of the whole body.
curative d. (CD, CD⁵⁰) 1. the quantity of any substance required to effect the cure of a disease or that will correct the manifestations of a deficiency of a particular factor in the diet; 2. effective d. used with therapeutically applied compounds. SEE ALSO: CD⁵⁰. SYN: therapeutic d..
daily d. the total amount of a remedy that is to be taken within 24 hours.
depth d. the d. of radiation at a distance beneath the surface, including secondary radiation or scatter, in proportion to the d. at the surface.
divided d. a definite fraction of a full d.; given repeatedly at short intervals so that the full d. is taken within a specified period, usually one day. SYN: fractional d..
effective d. (ED) 1. the d. that produces a specific effect; when followed by a subscript (generally “ED₅₀”), it denotes the d. having such an effect on a certain percentage ( e.g., 50%) of the test animals; ED₅₀ is the median effective d.; 2. in radiation protection, the sum of the equivalent doses in all tissues and organs of the body weighted for tissue effects of radiation. The SI unit of effective d. is the sievert (Sv) (=100 rem). 3. in diagnostic radiology, if a patient weighing W absorbs A joules of energy, and the experimentally derived ratio of effective d. to energy absorbed in an anthropomorphic phantom with mass M is R, then the effective d. is A·R· M/W. This formula results in a larger value for children despite their lesser absorption of radiation.
epilation d. the minimum amount of radiation sufficient to produce hair loss, usually in 10 to 14 days.
equianalgesic d. the qualitative ratio between actual milligram potency of comparable analgesics required to achieve the equivalent therapeutic effect.
equivalent d. in radiation protection, the absorbed d. averaged over a tissue or organ and weighted for the quality of the type of radiation. The unit of equivalent d. is the sievert.
erythema d. the minimum amount of x-rays or other form of radiation sufficient to produce erythema; historically, this d. was indicated by the Sabouraud meter as the B tint, the Holzknecht as 5(5H), the Hampson as 4, and the Kienbock as 10.
exit d. the exposure d. of radiation leaving a body opposite the portal of entry.
exposure d. the radiation d., expressed in roentgens, delivered at a point in free air. SYN: air d..
fractional d. SYN: divided d..
gonad d. the exposure d. to the male or female gonad, usually from incidental secondary radiation in diagnostic or therapeutic irradiation, or from whole-body irradiation. SYN: gonadal d..
gonadal d. SYN: gonad d..
initial d. SYN: loading d..
integral d. the total energy absorbed by the body, the product of the mass of tissue irradiated and the absorbed d.; unit, the gram rad.
L doses a group of terms that indicate the relative activity or potency of diphtheria toxin; the L doses are distinctly different from the minimal lethal d. and minimal reacting d., inasmuch as the latter two represent the direct effects of toxin, whereas the L doses pertain to the combining power of toxin with specific antitoxin. [“L” for L. limes, limit, boundary]
L⁺ d., L₊ d. alternatives for L&dag;, the limes tod d. of diphtheria toxin, i.e., the smallest amount of toxin that, when mixed with one unit of antitoxin and injected subcutaneously into a 250-g guinea pig, results in death of the animal within 96 hours (based on the average in a series); on theoretical grounds, one might expect that the difference between the L₊ and L₀ doses would be identical to 1 MLD, but this is not so in actual practice; with various toxic filtrates, the difference may range from several to more than 100 MLDs, indicating that the toxin-antitoxin combination is not a firm chemical union that occurs in constant proportions.
lethal d. (LD) the d. of a chemical or biologic preparation ( e.g., a bacterial exotoxin or a suspension of bacteria) that is likely to cause death; it varies in relation to the type of animal and the route of administration; when followed by a subscript (generally “LD₅₀” or median lethal d.), it denotes the d. likely to cause death in a certain percentage ( e.g., 50%) of the test animals; median lethal d. is LD₅₀, absolute lethal d. is LD₁₀₀, and minimal lethal d. is LD₀₅.
Lf d., L_f d. the limes flocculation d. of diphtheria toxin, i.e., the smallest amount of toxin that, when mixed with one unit of antitoxin, yields the most rapid flocculation in the Ramon test (in vitro); in general, the L_f d. is slightly less than the L_r d..
Lo d., L_o d. the limes nul d. of diphtheria toxin, i.e., the largest amount of toxin that, when mixed with one unit of antitoxin and injected subcutaneously into a 250-g guinea pig, yields no recognizable reaction in the average of a series; actually, the L_od. is usually recorded as the one that causes a barely perceptible local edema at the site of inoculation.
loading d. a comparatively large d. given at the beginning of treatment to start getting the effect of a drug, especially one with slow clearance thus requiring a long period to achieve stable blood levels without a high initial d.. SYN: initial d..
Lr d., L_r d. the limes reacting d. of diphtheria toxin, i.e., the smallest amount of toxin that, when mixed with one unit of antitoxin and injected intracutaneously in the shaved skin of a susceptible guinea pig, yields a minimal, positive reaction and inflammation localized to the region of the injection; the L_rd. closely approximates the L_od., as would be expected, inasmuch as a slight excess of unneutralized toxin results in a reaction.
maintenance d. maintenance drug therapy.
maximal d. the largest amount of a drug or physical procedure that an adult can take with safety.
maximal permissible d. See maximum permissible d..
maximum permissible d. (MPD) defined by the International Commission on Radiological Protection as the greatest d. of radiation which, in the light of present knowledge, is not expected to cause detectable bodily injury to persons at any time during their lifetime. This d. has been reduced with each Commission report. The MPD is given in terms of acute or chronic exposure of the whole body or of organs, systems, or regions of the body and differs for persons who are occupationally exposed versus the public at large.
maximum tolerated d. d. that produces grade 3 (severe) or grade 4 (life-threatening) toxicity in 30% or fewer of the patients tested.
median effective d. (ED₅₀) effective d..
minimal d. the smallest amount of a drug or physical procedure that will produce a desired physiologic effect in an adult.
minimal infecting d. (MID) the smallest quantity of infectious material regularly producing infection; usually expressed as I.D.₅₀, the quantity causing infection in 50% of a suitable series of animals or cells (cell cultures).
minimal lethal d. (MLD, mld) 1. the minimal d. of a toxic substance or infectious agent that is lethal, as assayed in various experimental animals ( e.g., the least amount of diphtheria toxin that, on an average, kills a 250-g guinea pig within 96 h after subcutaneous inoculation); when followed by a subscript (generally “MLD₅₀”), denotes the minimal d. that is lethal to a certain percentage ( e.g., 50%) of animals so assayed; 2. lD₀₅. See lethal d..
minimal reacting d. (MRD, mrd) the minimal d. of a toxic substance causing a reaction, as manifested in the skin of a series of susceptible test animals; the assay is based on the development of a characteristic, minimal but definite, “standard,” focal inflammation (congestion and edema, induration, degenerative changes, and desquamation of epidermal cells).
optimum d. the d. of a drug or radiation that will produce the desired effect with minimum likelihood of undesirable symptoms.
preventive d. the smallest amount of any substance that will prevent occurrence of symptoms of a disease or the consequences of a lack of a particular factor in the diet.
sensitizing d. in experimental anaphylaxis, the antigenic inoculum that renders an animal susceptible (sensitive) to anaphylactic shock following a subsequent inoculum (shocking d.) of the same antigen (anaphylactogen).
shocking d. in experimental anaphylaxis, the inoculum of antigen that causes anaphylactic shock in an animal sensitized by a previous inoculum (sensitizing d.) of the same antigen.
skin d. the absorbed d. of radiation delivered to the skin surface.
therapeutic d. SYN: curative d..
tissue culture infectious d. (TCID₅₀, TCD₅₀) the quantity of a cytopathogenic agent, such as a virus, that will produce a cytopathic effect in 50% of the cultures inoculated.
tolerance d. the largest d. of a remedy that can be accepted without the production of injurious symptoms.

dosimeter
dosimeter (do-sim′e-ter)

A device for measuring radiation, especially x-rays. [G. dosis, dose, + metron, measure]

dosimetry
dosimetry (do-sim′e-tre)

Measurement of radiation exposure, especially x-rays or gamma rays; calculation of radiation dose from internally administered radionuclides.
thermoluminescence d. the calculation of a radiation dose by measuring the light output after heating a special absorbent material ( e.g., lithium fluoride) placed in the radiation beam; the light output is proportional to the amount of radiation exposure.
x-ray d. SYN: roentgenometry.

dot
dot (dot)

A small spot.
Gunn dots minute, highly glistening, white or yellowish specks usually seen in the posterior part of the fundus; nonpathologic.
Horner-Trantas dots evanescent white cellular infiltrates occurring in the bulbar form of vernal keratoconjunctivitis.
Maurer dots finely granular precipitates or irregular cytoplasmic particles that usually occur diffusely in red blood cells infected with the trophozoites of Plasmodium falciparum, occasionally those of P. malariae; rarely observed in P. falciparum blood smears because its trophozoites seldom are seen in peripheral blood. SYN: Maurer clefts.
Mittendorf d. a small d. visible on the posterior aspect of the lens capsule on ophthalmologic examination that represents a remnant of the primitive hyaloid vascular system.
Schüffner dots fine, round, uniform red or red-yellow dots (as colored with Romanovsky stains) characteristically observed in erythrocytes infected with Plasmodium vivax and P. ovale, but not ordinarily found in P. malariae and P. falciparum infections. SYN: Schüffner granules.
Trantas dots pale, grayish red, uneven nodules of gelatinous aspect at the limbal conjunctiva in vernal conjunctivitis.
Ziemann dots fine dots seen in erythrocytes in malariae malaria. SYN: Ziemann stippling.

dotage
dotage (do′tij)

The deterioration of previously intact mental powers, common in old age.

doublet
doublet (dub′let)

1. A combination of two lenses designed to correct the chromatic and spherical aberration. 2. SYN: dipole. 3. Any sequence of two nucleotides in a polynucleotide strand. 4. A closely spaced pair of peaks or lines in a spectrum.
Wollaston d. a combination of two planoconvex lenses in the eyepiece of a microscope designed to correct the chromatic aberration.

douche
douche (doosh)

1. A current of water, gas, or vapor directed against a surface or projected into a cavity. 2. An instrument for giving a d.. 3. To apply a d.. [Fr. fr. doucher, to pour]

Douglas
Douglas

Claude G., English physiologist, 1882–1963. See D. bag.

Douglas
Douglas

Beverly, U.S. surgeon, 1891–1975.

Douglas
Douglas

James, Scottish anatomist in London, 1675–1742. See D. abscess, D. cul-de-sac, D. fold, D. line, D. pouch, cavum douglasi.

Douglas
Douglas

John C., Irish obstetrician, 1777–1850. See D. mechanism.

dovetail
dovetail (duv′tal)

A widened portion of a cavity preparation usually established to increase the retention and resistance form.

dowel
dowel (dow′l)

1. A cast gold or preformed metal pin placed into a root canal for the purpose of providing retention for a crown. 2. A preformed metal pin placed in a copper-plated die to provide a die stem. 3. A pin or rod that aligns or joins two structures by fitting into holes in both of them; dowels of various materials are used in orthopaedic surgery and dentistry. 4. SYN: d. graft.

Down
Down

John Langdon H., English physician, 1828–1896. See D. syndrome.

Downey
Downey

Hal, U.S. hematologist, 1877–1959. See D. cell.

downgrowth
downgrowth (doun-groth)

Something that grows downward; the process of growing in a downward direction.
epithelial d. the invasion of surface epithelium into the interior of the eye as a consequence of a penetrating ocular wound.

down-regulation
down-regulation

Development of a refractory or tolerant state consequent upon repeated administration of a pharmacologically or physiologically active substance; often accompanied by an initial decrease in affinity of receptors for the agent and a subsequent diminution in the number of receptors.

Downs
Downs

William B., U.S. orthodontist, 1899–1966. See D. analysis.

Dox
Dox

Arthur W., U.S. chemist, *1882. See Czapek-D. medium.

doxacurium chloride
doxacurium chloride (doks′a-koo′re-um)

A nondepolarizing neuromuscular blocking drug similar to pancuronium but without cardiovascular side effects.

doxapram hydrochloride
doxapram hydrochloride (doks′a-pram)

A central nervous system stimulant, advocated but infrequently used as a respiratory stimulant in anesthesia.

doxazocin
doxazocin (doks′a-zo-sin)

An antihypertensive agent that selectively blocks the α₁ (postjunctional) subtype of α-adrenergic receptors; resembles prazocin in pharmacologic actions. Prevents the blood pressure elevating effects of norepinephrine, phenylephrine, and other agonists at vascular α₁-receptors.

doxepin hydrochloride
doxepin hydrochloride (dok′se-pin)

An antidepressant agent.

doxophylline
doxophylline (doks′o-fil′in)

A theophyllinelike drug used, though rarely in the U.S., as a bronchodilator in asthma and chronic obstructive pulmonary disease.

doxorubicin
doxorubicin (dok′so-roo′bi-sin)

An antineoplastic antibiotic isolated from Streptomyces peucetius; also used in cytogenetics to produce Q-type chromosome bands. SYN: adriamycin.

doxycycline
doxycycline (dok-se-si′klen)

A broad-spectrum antibiotic.

doxylamine succinate
doxylamine succinate (dok-sil′a-men)

An antihistaminic. SYN: mereprine.

Doyère
Doyère

Louis, French physiologist, 1811–1863. See D. eminence.

Doyle
Doyle

J.B., U.S. gynecologist, *1907. See D. operation.

Doyne
Doyne

Robert Walter, English ophthalmologist, 1857–1916. See D. honeycomb choroidopathy.

D.P.
D.P.

Abbreviation for Doctor of Podiatry.

D.P.H.
D.P.H.

Abbreviation for Department of Public Health; Doctor of Public Health; Diploma of Public Health.

D.P.M.
D.P.M.

Abbreviation for Doctor of Podiatric Medicine.

DPT
DPT

Abbreviation for diphtheria-pertussis-tetanus (vaccine). See diphtheria toxoid, tetanus toxoid, and pertussis vaccine.

DR
DR

Abbreviation for digital radiography.

Dr. Dr.

Abbreviation for doctor.

dr
dr

Abbreviation for dram.

drachm
drachm (dram)

SYN: dram. [G. drachme, an ancient Greek weight, equivalent to about 60 gr]

dracunculiasis
dracunculiasis, dracunculosis (dra-kung-ku-li′a-sis, -ku-lo′sis)

Infection with Dracunculus medinensis.

Dracunculus
Dracunculus (dra-kung′ku-lus)

A genus of nematodes (superfamily Dracunculoidea) that have some resemblances to true filarial worms; however, adults are larger (females being as long as 1 m), and the intermediate host is a freshwater crustacean rather than an insect. [L. dim. of draco, serpent]
D. lova old incorrect term for Loa loa.
D. medinensis a species of skin-infecting, yard-long nematodes, formerly incorrectly classed as Filaria; adult worms live anywhere in the body of humans and various semi-aquatic mammals; the females migrate along fascial planes to subcutaneous tissues, where troublesome chronic ulcers are formed in the skin; when the host enters water, larvae are discharged from the ulcers, from which the head of the female worm protrudes; these larvae, if ingested by Cyclops species, develop in the intermediate host to the infective stage; humans and various animals contract the infection from accidental ingestion of infected Cyclops in drinking water. Popularly known as guinea, Medina, serpent, or dragon worm, and frequently thought to be the “fiery serpent” that plagued the Israelites. [L. of Medina]
D. oculi old incorrect term for Loa loa.
D. persarum old term for D. medinensis. [L. of the Persians]

draft
draft

1. A current of air in a confined space. 2. A quantity of liquid medicine ordered as a single dose. SYN: draught.

drag
drag

1. The lower or cast side of a denture flask. 2. Any tendency for one moving thing to pull something else along with it.
solvent d. the influence exerted by a flow of solvent through a membrane on the simultaneous movement of a solute through the membrane.

dragée
dragée (dra-zha′)

A sugar-coated pill or capsule. [Fr.]

Dragendorff
Dragendorff

Georg J.N., German physician and pharmaceutical chemist, 1836–1898. See D. test.

Drager
Drager

Glenn A., U.S. neurologist, *1917. See Shy-D. syndrome.

Dräger
Dräger

Heinrich, German manufacturer of industrial and diving respiratory apparatus and anesthesia machines, 1847–1917. See D. respirometer.

drain
drain (dran)

1. To remove fluid from a cavity as it forms, e.g., to d. an abscess. 2. A device, usually in the shape of a tube or wick, for removing fluid as it collects in a cavity, especially a wound cavity. [A. S. drehnian, to draw off]
cigarette d. a wick of gauze wrapped in a thin, soft rubberlike material, providing capillary drainage.
Mikulicz d. a d. made of several strings of gauze held together by a single layer of gauze.
Penrose d. a soft, tubular, rubberlike d..
stab d. a d. passed into a cavity through a puncture made at a dependent part away from the wound of operation, designed to prevent infection of the wound.
sump d. a d. consisting of an outer tube vented to the outside with a smaller tube within it which is attached to a suction pump; both have multiple perforations that allow fluid and air to be carried away through the suction tube.

drainage
drainage (dran′ij)

Continuous withdrawal of fluids from a wound or other cavity.
capillary d. d. by means of a wick of gauze or other material.
closed d. d. of a body cavity via a water- or air-tight system. Cf.:sump drain.
dependent d. d. from the lowest part and into a receptacle at a level lower than the structure being drained. SYN: downward d..
downward d. SYN: dependent d..
infusion-aspiration d. a type of d. in which antibiotics are continuously infused into a cavity at the same time fluid is being drained (aspirated) from the cavity.
open d. d. allowing air to enter.
postural d. d. used in bronchiectasis and lung abscess. The patient's body is positioned so that the trachea is inclined downward and below the affected chest area.
suction d. closed d. of a cavity, with a suction apparatus attached to the d. tube.
through d. d. obtained by the passage of a perforated tube, open at both extremities, through a cavity; in addition, the cavity can be washed out by a solution passed through the tube.
tidal d. d. of the urinary bladder by means of an intermittent filling and emptying apparatus.
Wangensteen d. continuous d. by suction through an indwelling gastric or duodenal tube.

dram
dram (dr)

A unit of weight: ¹/₈ oz.; 60 gr, apothecaries' weight; ¹/₁₆ oz., avoirdupois weight. SYN: drachm. [see drachm]

drape
drape (drap)

1. To cover parts of the body other than those to be examined or operated upon. 2. The cloth or materials used for such cover. [M.E., fr. L.L. drappus, cloth]

Draper
Draper

John William, English chemist, 1811–1882. See D. law.

draught
draught (draft)

SYN: draft.

draw-sheet
draw-sheet (draw′shet)

A narrow sheet placed crosswise on the bed under the patient to assist in moving the patient or in changing soiled bed coverings.

dream
dream (drem)

Mental activity during sleep in which events, thought, emotions, and images are experienced as real.
anxiety d. a d. (or nightmare) in which morbid fear and anxiety form an important part.
wet d. a true physiologic orgasm during sleep including, in males, a nocturnal seminal emission usually accompanying a d. with sexual content.

dream-work
dream-work

In psychoanalysis, the process by which the change from latent to manifest content of a dream is effected.

Drechslera
Drechslera (dresh′ler-a)

A saprobic genus of fungi, frequently recovered in the clinical laboratory, characterized by conidia attached to a zigzagged conidiophore. Most species in this genus that cause phaeohyphomycosis in humans, cats, and horses have been transferred to the genera Bipolaris or Exserohilum.

Dreifuss
Dreifuss

Fritz E., *1926. See Emery-D. muscular dystrophy.

drepanidium
drepanidium (drep-a-nid′e-um)

A young sickle-shaped or crescentic form of a gregarine. [G. drepane, a sickle]

drepanocyte
drepanocyte (drep′a-no-sit)

SYN: sickle cell. [G. drepane, sickle, + kytos, a hollow (cell)]

drepanocytic
drepanocytic (drep′a-no-sit′ik)

Relating to or resembling a sickle cell.

dresser
dresser (dres′er)

In Great Britain, a surgical assistant whose primary duty is bandaging and dressing wounds.

dressing
dressing (dres′ing)

The material applied, or the application itself of material, to a wound for protection, absorbance, drainage, etc.
adhesive absorbent d. a sterile individual d. consisting of a plain absorbent compress affixed to a film of fabric coated with a pressure-sensitive adhesive.
antiseptic d. a sterile d. of gauze impregnated with an antiseptic.
bolus d. SYN: tie-over d..
dry d. dry gauze or other material applied to a wound.
fixed d. a d. stiffened with a substance that produces immobilization when it dries.
Lister d. the first type of antiseptic d., one of gauze impregnated with carbolic acid.
occlusive d. a d. that hermetically seals a wound.
pressure d. a d. by which pressure is exerted on the area covered to prevent the collection of fluids in the underlying tissues; most commonly used after skin grafting and in the treatment of burns.
tie-over d. a d. placed over a skin graft or other sutured wound and tied on by the sutures which have been left of sufficient length for that purpose. SYN: bolus d..
water d. an application of gauze or other material that is kept wet with sterilized water or saline solution.
wet-to-dry d. a d. that is applied moist with saline and allowed to dry before it is removed.

Dressler
Dressler

William, U.S. physician, 1890–1969. See D. beat, D. syndrome.

Dreyer
Dreyer

Georges, English pathologist, 1873–1934. See D. formula.

DRG
DRG

Abbreviation for diagnosis-related group.

dribble
dribble (dri′bl)

1. To drool, slaver, drivel. 2. To fall in drops, as the urine from a distended bladder.

drift
drift

1. A gradual movement, as from an original position. 2. A gradual change in the value of a random variable over time as a result of various factors, some random and some systematic effects of trend, manipulation, etc.
antigenic d. the process of “evolutionary” changes in molecular structure of DNA/RNA in microorganisms during their passage from one host to another; it may be due to recombination, deletion, or insertion of genes, point mutations or combinations of these events; it leads to alteration (usually slow and progressive) in the antigenic composition, and therefore in the immunologic responses of individuals and populations to exposure to the microorganism concerned; common with influenzavirus.
genetic d. a change in the frequencies of genetic traits or allele frequencies over generations.
pure random d. that which has random components only with an average value of zero and no systematic effects. Brownian movement in a still container shows pure random d. but in the Mississippi shows a steady downstream tendency.

drifting
drifting

Random movement of a tooth to a position of greater stability.

drifts
drifts (drifts)

Slow ocular movements of greater amplitude than flicks, occurring during ocular fixation. SYN: drift movements.

drill
drill

1. To make a hole in bone or other hard substance. 2. An instrument for making or enlarging a hole in bone or in a tooth. [Middle Dutch drillen, to bore]
bur d. bur.
dental d. a rotary power-driven instrument into which cutting points may be inserted. SEE ALSO: handpiece.

drill-out
drill-out

A drilling away; scooping out.
cochlear d. implantation of electrodes in a cochlea in which the lumen of the scala tympani has been obliterated by the deposition of new bone due to the inflammatory process in labyrinthitis; the cochlear wall and new bone are drilled away so that the electrodes can be placed close to the remaining neurons of the auditory division of the 8th cranial nerve.

Drinker
Drinker

Philip, U.S. industrial hygienist, 1893–1972. See D. respirator.

drip
drip

1. To flow a drop at a time. 2. A flowing in drops.
alkaline milk d. a variable mixture of sodium bicarbonate in whole milk dripped into the stomach through a small oral or nasal tube to produce constant achlorhydria; a now obsolete therapy for certain ulcers.
intravenous d. the slow but continuous introduction of solutions intravenously, a drop at a time.
Murphy d. SYN: proctoclysis.
postnasal d. term sometimes used to describe sensation of mucoid or mucopurulent discharge from the posterior nares.

drive
drive

1. In psychoanalysis, a basic compelling urge. 2. In psychology, classified as either innate ( e.g., hunger) or learned ( e.g., hoarding) and appetitive ( e.g., hunger, thirst, sex) or aversive ( e.g., fear, pain, grief). SEE ALSO: motive, motivation.
acquired drives SYN: secondary drives.
exploratory d. the d. typical of toddlers and some animals to investigate the unfamiliar or unknown.
learned d. SYN: motive (1) .
meiotic d. differential fitness in males and females.
physiological drives those drives such as hunger and thirst which stem from the biological needs of an organism. SYN: primary drives.
primary drives SYN: physiological drives.
secondary drives those drives not directly related to biological needs; a secondary d. can be learned as an offshoot of a primary d., in which case it is often referred to as a motive. SYN: acquired drives.

driving
driving (driv′ing)

The induction of a frequency in the electroencephalogram by sensory stimulation at this frequency.
photic d. a normal EEG phenomenon whereby the frequency of the activity recorded over the parieto-occipital regions is time-locked to the flash frequency during photic stimulation.

dromomania
dromomania (drom-o-ma′ne-a)

An uncontrollable impulse to wander or travel. [G. dromos, a running, + mania, insanity]

dromostanolone propionate
dromostanolone propionate (dro-mos′tan-o-lon, dro-mo-stan′o-lon)

An antineoplastic agent.

dronabinol
dronabinol (dro-nab′i-nol)

The principal psychoactive substance present in Cannabis sativa, used therapeutically as an antinauseant to control the nausea and vomiting associated with cancer chemotherapy. SEE ALSO: tetrahydrocannabinol.

drop
drop

1. To fall, or to be dispensed or poured in globules. 2. A liquid globule. 3. A volume of liquid regarded as a unit of dosage, equivalent in the case of water to about 1 minim. SEE ALSO: drops. 4. A solid confection in globular form, usually intended to be allowed to dissolve in the mouth. [A.S. droppan]
enamel d. SYN: enameloma.
hanging d. a d. of liquid on the undersurface of the object glass for examination under the microscope.

droperidol
droperidol (dro-per′i-dol)

A butyrophenone drug used in neuroleptanalgesia and preanesthetic medication; the pharmacology is similar to that of haloperidol; a dopamine receptor blocker. Exhibits antiemetic effects.

dropfoot
dropfoot

See footdrop.

droplet
droplet (drop′let)

A diminutive drop, such as a particle of moisture discharged from the mouth during coughing, sneezing, or speaking; these may transmit infections to others by their airborne passage. [drop + -let, dim. suffix]

dropper
dropper

SYN: instillator.

drops
drops

A popular term for a medicine taken in doses measured by d., usually a tincture, or applied by dropping, as an eyewash.
eye d. See eyewash, ophthalmic solutions, under solution.
knock-out d. a popular name for chloral alcoholate given with criminal intent to produce unconsciousness rapidly; it is formed by adding chloral hydrate to beer or some stronger alcoholic liquor.
nose d. a liquid preparation intended for intranasal administration with a medicine dropper. Most frequently used for decongestion of the nasal passages but can be used for any other appropriate indication.
stomach d. a stomachic tonic, usually tincture of gentian, alone or with other stomachics.

dropsical
dropsical (drop′si-kal)

SYN: hydropic.

dropsy
dropsy (drop′se)

Old term for generalized edema, most often associated with cardiac failure. [G. hydrops]
abdominal d. SYN: ascites.
cardiac d. edema due to heart failure.
epidemic d. a disease causing occasional epidemics in India and Mauritius; marked by edema, anemia, eruptive angiomatosis, and mild fever; may be associated with nutritional deficiency.
famine d. edema occurring with the hypoproteinemia of low protein intake occurring as starvation of a large population group.
nutritional d. edema due to hypoproteinemia secondary to malnutrition.
d. of pericardium SYN: pericardial effusion.

drowning
drowning

Death within 24 hours of immersion in liquid, either due to anoxia or cardiac arrest caused by sudden extreme lowering of temperature (immersion syndrome). SEE ALSO: near d..
dry d. d. by asphyxiation in an individual whose laryngeal reflexes are brisk, resulting in spasm that prevents inhalation of water; may be associated with the highest recovery rate.
near d. initial survival following immersion in liquid; the victim may die more than 24 hours later, e.g., from ARDS.
secondary d. pulmonary edema and resulting asphyxia, resulting from hypoxia and increased permeability of pulmonary capillaries occurring in a patient who has been immersed in and aspirated some water.

drowsiness
drowsiness (drow′ze-nes)

A state of impaired awareness associated with a desire or inclination to sleep.

Dr.P.H.
Dr.P.H.

Abbreviation of Doctor of Public Health.

drug
drug (drug)

1. Therapeutic agent; any substance, other than food, used in the prevention, diagnosis, alleviation, treatment, or cure of disease. For types or classifications of drugs, see the specific name. SEE ALSO: agent. 2. To administer or take a d., usually implying an overly large quantity or a narcotic. 3. General term for any substance, stimulating or depressing, that can be habituating or addictive, especially a narcotic. [M.E. drogge]
addictive d. any d. that creates a certain degree of euphoria and has a strong potential for addiction.
crude d. an unrefined preparation, usually of plant origin, that occurs either in the entire, nearly entire, broken, cut, or powdered state.
disease modifying antirheumatic drugs agents that apparently alter the course and progression of rheumatoid arthritis, as opposed to more rapidly acting substances that suppress inflammation and decrease pain, but do not prevent cartilage or bone erosion or progressive disability.
d. holiday interval when a chronically medicated patient temporarily stops taking the medication; used to allow some recuperation of normal functions, to maintain sensitivity to the d., and to reduce the likelihood of side-effects.
nonsteroidal anti-inflammatory drugs (NSAID) a large number of drugs exerting anti-inflammatory (and also usually analgesic and antipyretic) actions; examples include aspirin, acetaminophen, diclofenac, indomethacine, ketorolac, ibuprofen, and naproxen. A contrast is made with steroidal compounds (such as hydrocortisone or prednisone) exerting anti-inflammatory activity.
orphan drugs SYN: orphan products, under product.
psychedelic d. SYN: hallucinogen.
psychodysleptic d. SYN: hallucinogen.
psycholytic d. SYN: hallucinogen.
psychotomimetic d. SYN: hallucinogen.
psychotropic d. any d. that affects the mind.
recreational d. SYN: street d..
scheduled d. a d. assigned to any of the five schedules in the Controlled Substances Act (1970). SEE ALSO: controlled substance.
street d. a controlled substance taken for non-medical purposes. Street drugs comprise various amphetamines, anesthetics, barbiturates, opiates, and psychoactive drugs, and many are derived from natural sources ( e.g., the plants Papaver somniferum, Cannibis sativa, Amanita pantherina, Lophophora williamsii). Slang names include acid (lysergic acid diethylamide), angel dust (phencyclidine), coke (cocaine), downers (barbiturates), grass (marijuana), hash (concentrated tetrahydrocannibinol), magic mushrooms (psilocybin), and speed (amphetamines). During the 1980s, a new class of “designer drugs” arose, mostly analogs of psychoactive substances intended to escape regulation under the Controlled Substances Act. Also, crack cocaine, a potent, smokable form of cocaine, emerged as a major public health problem. In the U.S. illicit use of drugs such as cocaine, marijuana, and heroin historically has occurred in cycles. SYN: recreational d..

drug-fast
drug-fast

Pertaining to microorganisms that resist or become tolerant to an antibacterial agent.

druggist
druggist (drug′ist)

Old common term for pharmacist.

drug interactions
drug interactions

The pharmacological result, either desirable or undesirable, of drugs interacting with other drugs, with endogenous physiologic chemical agents ( e.g., MAOI with epinephrine), with components of the diet, and with chemicals used in diagnostic tests or the results of such tests.

drum
drum, drumhead (drum, drum′hed)

SYN: tympanic membrane.

Drummond
Drummond

Sir David, English physician, 1852–1932. See artery of D., D. sign.

drunkenness
drunkenness (drunk′en-nes)

Intoxication, usually alcoholic. SEE ALSO: acute alcoholism.
sleep d. a half-waking condition in which the faculty of orientation is in abeyance, and under the influence of nightmarelike ideas the person may become actively excited and violent. SYN: somnolentia (2) .

drusen
drusen (droo′sen)

Small bright structures seen in the retina and in the optic disk. [Ger. pl. of Druse, stony nodule, geode]
basal laminar d. small, round, translucent lesions measuring 25–75 μm in diameter, which represent nodular thickening of the basement membrane of the retinal pigment epithelium, often with an overlying focal detachment of the retinal pigment epithelium from Bruch membrane. SYN: cuticular d..
basal linear d. deposits of long-spaced collagen located between the plasma membrane and basement membrane of the retinal pigment epithelium.
cuticular d. SYN: basal laminar d..
exudative d. accumulations of an amorphous and granular material, cytoplasmic processes, and bent fibers between the basement membrane of the retinal pigment epithelium and the inner collagenous zone of Bruch membrane; types of exudative d. include hard d. and soft d.. SYN: typical d..
hard d. type of exudative or typical d. that appear ophthalmoscopically as discrete, yellow nodules characterized histopathologically by well-defined accumulations of hyaline material in the inner and outer collagenous zones of Bruch membrane.
intrapapillary d. SYN: d. of the optic nerve head.
d. of the macula excrescences of Bruch membrane that produce a window in the retinal pigment epithelium and are a feature of age-related macular retinal degeneration. SYN: macular d..
macular d. SYN: d. of the macula.
d. of the optic nerve head basophilic, laminated, calcareous acellular masses that resemble crystals within the nerve head, anterior to the lamina cribrosa, that may simulate papilledema and/or cause visual field defects. SYN: intrapapillary d..
soft d. type of exudative d. that appear ophthalmoscopically as placoid, yellow lesions characterized histopathologically by localized serous detachments of the retinal pigment epithelium from the Bruch membrane.
typical d. SYN: exudative d..

dry ice
dry ice (dri is)

SYN: carbon dioxide snow.

ds
ds

Abbreviation for double-stranded.

DSA
DSA

Abbreviation for digital subtraction angiography.

DSM
DSM

Abbreviation for the Diagnostic and Statistical Manual of Mental Disorders.

DT
DT

Abbreviation for delirium tremens.

dT
dT

Abbreviation for deoxythymidine.

DTaP
DTaP

Abbreviation for diphtheria, tetanus, and acellular pertussis vaccine.

DT-diaphorase
DT-diaphorase

SYN: NADPH dehydrogenase (quinone).

dTDP
dTDP

Abbreviation for thymidine 5′-diphosphate.

dTDP-sugars
dTDP-sugars

Sugars or sugar derivatives bonded to dTDP.

DTH
DTH

Abbreviation for delayed-type hypersensitivity.

dThd
dThd

Abbreviation for thymidine.

DTIC
DTIC

Abbreviation for dacarbazine.

dTMP
dTMP

Abbreviation for deoxythymidylic acid; thymidine 5′-monophosphate.

DTP
DTP

Abbreviation for distal tingling on percussion; diphtheria toxoid, tetanus toxoid, and pertussis vaccine; and Demerol, Thorazine, and Phenergan, sometimes used as a sedative.

DTPA
DTPA

Abbreviation for diethylenetriamine pentaacetic acid.

DTPA
DTPA

Abbreviation for diethylenetriamine pentaacetic acid.

DTR
DTR

Abbreviation for deep tendon reflex.

dTTP
dTTP

Abbreviation for thymidine 5′-triphosphate.

dualism
dualism (doo′al-izm)

1. In chemistry, a theory advanced by Berzelius that every compound, no matter how many elements enter into it, is composed of two parts, one electrically negative, the other positive; still applicable, with modification, to polar compounds, but inapplicable to nonpolar compounds. 2. In hematology, the concept that blood cells have two origins, i.e., lymphogenous and myelogenous. 3. The theory that the mind and body are two distinct systems, independent and different in nature. [L. dualis, relating to two, fr. duo, two]

Duane
Duane

Alexander, U.S. ophthalmologist, 1858–1926. See D. syndrome.

Dubin
Dubin

I. Nathan, U.S. pathologist, 1913–1980. See D.-Johnson syndrome.

DuBois
DuBois

Eugene F., U.S. physiologist, 1882–1959. See D. formula, Aub-D. table.

Dubois
Dubois

Paul A., French obstetrician, 1795–1871. See D. abscesses, under abscess, D. disease.

duboisine
duboisine (doo-boy′sen)

An alkaloid obtained from the leaves of Duboisia myoporoides (family Solanaceae). See hyoscyamine.

Du Bois-Reymond
Du Bois-Reymond

Emil H., German physiologist, 1818–1896. See Du Bois-Reymond law.

Duboscq
Duboscq

Jules, French optician, 1817–1886. See D. colorimeter.

Dubowitz
Dubowitz

Victor, South African-English pediatrician, *1931. See D. score.

Dubreuil-Chambardel
Dubreuil-Chambardel

Louis, French dentist, 1879–1927. See Dubreuil-Chambardel syndrome.

Duchenne
Duchenne

Guillaume B.A., French neurologist, 1806–1875. See D. disease, D. sign, D.-Aran disease, Aran-D. disease, D.-Erb paralysis, D. dystrophy.

Duckworth
Duckworth

Sir Dyce, English physician, 1840–1928. See D. phenomenon.

Ducrey
Ducrey

Augusto, Italian dermatologist, 1860–1940. See D. bacillus, D. test.

duct
duct (dukt) [TA]

A tubular structure giving exit to the secretion of a gland or organ, capable of conducting fluid. SEE ALSO: canal. SYN: ductus [TA] . [L. duco, pp. ductus, to lead]
aberrant ducts SYN: aberrant ductules, under ductule.
aberrant bile ducts small ducts occasionally present in the ligaments of the liver or originating from the surface of the liver.
accessory pancreatic d. [TA] the excretory d. of the head of the pancreas, one branch of which joins the pancreatic d., the other opening independently into the duodenum at the lesser duodenal papilla. SYN: ductus pancreaticus accessorius [TA] , Bernard canal, Bernard d., ductus dorsopancreaticus, Santorini canal, Santorini d..
alveolar d. 1. the part of the respiratory passages distal to the respiratory bronchiole; from it arise alveolar sacs and alveoli; 2. the smallest of the intralobular ducts in the mammary gland, into which the secretory alveoli open. SYN: ductulus alveolaris.
amnionic d. the transitory opening between the seroamnionic folds in birds just before they fuse to form the seroamnionic raphe.
anal ducts short ducts lined with simple columnar to stratified columnar epithelium that extend from the valvulae anales to the sinus anales.
arterial d. SYN: ductus arteriosus.
Bartholin d. SYN: major sublingual d..
Bellini ducts SYN: papillary ducts.
Bernard d. SYN: accessory pancreatic d..
bile d. 1. a d. formed by the union of the hepatic and cystic ducts; it discharges at the duodenal papilla. SYN: ductus choledochus [TA] , choledoch d., choledoch, choledochus, common bile d.. 2. any of the ducts conveying bile between the liver and the intestine, including hepatic, cystic, and common bile d.. a d. formed by the union of the hepatic and cystic ducts; it discharges at the duodenal papilla. SYN: ductus biliaris [TA] , biliary d..
biliary d. SYN: bile d. (2) .
Blasius d. SYN: parotid d..
Botallo d. SYN: ductus arteriosus.
bucconeural d. SYN: craniopharyngeal d..
d. of bulbourethral gland [TA] the long slender d. on each side passing down through the inferior fascia of the urogenital diaphragm to enter the bulb of the penis and course forward 2 or 3 cm before terminating in the urethra. SYN: ductus glandulae bulbourethralis [TA] .
canalicular ducts 1. SYN: lactiferous ducts. 2. SYN: biliary ductules, under ductule.
carotid d. SYN: ductus caroticus.
cervical d. See cervical diverticulum.
choledoch d. SYN: bile d. (1) .
cochlear d. [TA] a spirally arranged membranous tube suspended within the cochlea, lying between and separating the scala vestibuli and scala tympani; it begins by a blind extremity, the vestibular cecum, in the cochlear recess of the vestibule, terminating in another blind extremity, the cecum cupulare or lagena, at the cupola of the cochlea; it contains endolymph and communicates with the sacculus by the ductus reuniens; the spiral organ (of Corti), the neuroepithelial receptor organ for hearing, occupies the floor of the d.. SYN: ductus cochlearis [TA] , Löwenberg canal, Löwenberg scala, membranous cochlea, scala media.
common bile d. SYN: bile d. (1) .
common hepatic d. [TA] the part of the biliary d. system that is formed by the confluence of right and left hepatic ducts. At the porta hepatis it is joined by the cystic d. to become the common bile d.. SYN: ductus hepaticus communis [TA] , hepatocystic d..
craniopharyngeal d. the slender tubular part of the hypophysial diverticulum; the stalk of Rathke pocket. SYN: bucconeural d., hypophysial d..
Cuvier ducts obsolete term for the common cardinal veins.
cystic d. [TA] the ductus leading from the gallbladder; it joins the hepatic d. to form the common bile d.. SYN: ductus cysticus [TA] , cystic gall d..
cystic gall d. SYN: cystic d..
deferent d. SYN: ductus deferens.
efferent d. SYN: efferent ductules of testis, under ductule.
ejaculatory d. [TA] the d. formed by the union of the deferent d. and the excretory d. of the seminal vesicle, which opens into the prostatic urethra. SYN: ductus ejaculatorius [TA] , spermiduct (2) .
endolymphatic d. [TA] a small membranous canal, connecting with both saccule and utricle of the membranous labyrinth, passing through the aqueduct of vestibule, and terminating in a dilated blind extremity, the endolymphatic sac, on the posterior surface of the petrous portion of the temporal bone beneath the dura mater. SYN: ductus endolymphaticus [TA] .
d. of epididymis [TA] a convoluted tube into which the efferent ductules open and which itself terminates in the ductus deferens. SYN: ductus epididymidis [TA] .
excretory d. a d. carrying the secretion from a gland or a fluid from any reservoir. SYN: ductus excretorius.
excretory ducts of lacrimal gland the multiple (6–10) excretory ducts of the lacrimal gland that open into the superior fornix of the conjunctival sac. SYN: ductuli excretorii glandulae lacrimalis, excretory ductules of lacrimal gland.
excretory d. of seminal gland [TA] the passage leading from a seminal vesicle to the ejaculatory d.. SYN: ductus excretorius vesiculae seminalis [TA] , excretory d. of seminal vesicle&star.
excretory d. of seminal vesicle excretory d. of seminal gland.
frontonasal d. the passage that leads downward from the frontal sinus to open into the ethmoidal infundibulum.
galactophorous ducts SYN: lactiferous ducts.
gall d. obsolete term for bile d..
Gartner d. SYN: longitudinal d. of epoöphoron.
genital d. SYN: genital tract.
guttural d. SYN: pharyngotympanic (auditory) tube.
hemithoracic d. an accessory thoracic d., usually emptying into the thoracic d. but sometimes discharging independently into the right subclavian vein. SYN: ductus hemithoracicus.
Hensen d. SYN: ductus reuniens.
hepatic d. See common hepatic d., right hepatic d., left hepatic d..
hepatocystic d. SYN: common hepatic d..
Hoffmann d. SYN: pancreatic d..
hypophysial d. SYN: craniopharyngeal d..
incisive d. [TA] an infrequent rudimentary d., or protrusion of the mucous membrane into the incisive canal, on either side of the anterior extremity of the nasal crest. SYN: ductus incisivus [TA] .
intercalated ducts the minute ducts of glands, such as the salivary and the pancreas, that lead from the acini; they are lined by low cuboidal cells.
interlobar d. a d. draining the secretion of the lobe of a gland and formed by the junction of a number of interlobular ducts.
interlobular d. any d. leading from a lobule of a gland and formed by the junction of the intralobular ducts.
intralobular d. a d. that lies within a lobule of a gland.
jugular d. SYN: jugular lymphatic trunk.
lactiferous ducts [TA] one of the ducts, numbering 15–20, which drain the lobes of the mammary gland; they open at the nipple. SYN: ductus lactiferi [TA] , canalicular ducts (1) , galactophore, galactophorous canals, galactophorous ducts, mamillary ducts, mammary ducts, milk ducts, tubuli galactophori, tubuli lactiferi.
left d. of caudate lobe of liver [TA] a tributary to the left hepatic d. draining bile from the left half of the caudate lobe. SYN: ductus lobi caudati sinister hepatis [TA] .
left hepatic d. [TA] the d. that drains bile from the left half of the liver, including the quadrate lobe and the left part of the caudate lobe. SYN: ductus hepaticus sinister [TA] .
longitudinal d. of epoöphoron [TA] a rudimentary vestige of the mesonephric d. in the female into which the tubules of the epoöphoron open; it is located in the broad ligament of the uterus, parallel with the lateral part of the uterine tube, and in the lateral walls of the cervix and vagina. SYN: ductus longitudinalis epoöphori [TA] , ductus deferens vestigialis, Gartner canal, Gartner d..
Luschka ducts glandlike tubular structures in the wall of the gallbladder, especially in the part covered with peritoneum.
lymphatic d. one of the two large lymph channels, right lymphatic d. or thoracic d..
major sublingual d. [TA] the d. that drains the anterior portion of the sublingual gland; it opens at the sublingual papilla. SYN: ductus sublingualis major [TA] , Bartholin d..
mamillary ducts SYN: lactiferous ducts.
mammary ducts SYN: lactiferous ducts.
mesonephric d. a d. in the embryo draining the mesonephric tubules; in the male it becomes the ductus deferens; in the female it becomes vestigial. SEE ALSO: longitudinal d. of epoöphoron. SYN: ductus mesonephricus, wolffian d..
metanephric d. the slender tubular portion of the metanephric diverticulum; the primordium of the epithelial lining of the ureter. See epoophoron, longitudinal d. of epoöphoron.
milk ducts SYN: lactiferous ducts.
minor sublingual ducts [TA] from 8–20 small ducts of the sublingual salivary gland that open into the mouth on the surface of the sublingual fold; a few join the submandibular ducts. SYN: ductus sublinguales minores [TA] , Rivinus ducts, Walther canals, Walther ducts.
Müller d., müllerian d. SYN: paramesonephric d..
nasal d. SYN: nasolacrimal d..
nasolacrimal d. [TA] the passage leading downward from the lacrimal sac on each side to the anterior portion of the inferior meatus of the nose, through which tears are conducted into the nasal cavity. SYN: ductus nasolacrimalis [TA] , nasal d..
nephric d. SYN: pronephric d..
omphalomesenteric d. obsolete term for yolk stalk.
pancreatic d. [TA] the excretory d. of the pancreas that extends through the gland from tail to head where it empties into the duodenum at the greater duodenal papilla. SYN: ductus pancreaticus [TA] , Hoffmann d., Wirsung canal, Wirsung d..
papillary ducts the largest straight excretory ducts in the kidney medulla and papillae whose openings form the area cribrosa that open into a minor calyx; they are a continuation of the collecting tubules. SYN: Bellini ducts.
paramesonephric d. either of the two paired embryonic tubes extending along the mesonephros roughly parallel to the mesonephric d. and emptying into the cloaca; in the female, the upper parts of the ducts form the uterine tubes, while the lower fuse to form the uterus and part of the vagina; in the male, vestiges of the ducts form the vagina masculina and the appendix testis. SYN: ductus paramesonephricus, Müller d., müllerian d..
paraurethral ducts [TA] inconstant ducts along the side of the female urethra that convey the mucoid secretion of Skene glands to the vestibule. SYN: ductus paraurethrales [TA] , ducts of Skene glands, Schüller ducts.
parotid d. [TA] the d. of the parotid gland opening from the cheek into the vestibule of the mouth opposite the neck of the superior second molar tooth. SYN: ductus parotideus [TA] , Blasius d., Stensen d., Steno d..
Pecquet d. SYN: thoracic d..
perilymphatic d. SYN: cochlear aqueduct.
pharyngobranchial ducts ductus pharyngobranchialis III, ductus pharyngobranchialis IV.
pronephric d. the d. of the pronephros. SYN: nephric d..
prostatic ducts SYN: prostatic ductules, under ductule.
right d. of caudate lobe of liver [TA] the bile d. from the right half of the caudate lobe, a tributary to the right hepatic d.. SYN: ductus lobi caudati dexter hepatis [TA] .
right hepatic d. [TA] the d. that transmits bile to the common hepatic d. from the right half of the liver and the right part of the caudate lobe. SYN: ductus hepaticus dexter [TA] .
right lymphatic d. [TA] one of the two terminal lymph vessels, a short trunk, about 2 cm in length, formed by the union of the right jugular lymphatic vessel and vessels from the lymph nodes of the right superior limb, thoracic wall, and both lungs; it lies on the right side of the root of the neck and empties into the right brachiocephalic vein. Frequently, no right lymphatic d. is formed, with the vessels that normally contribute to its formation entering the venous system independently. SYN: ductus lymphaticus dexter [TA] , ductus thoracicus dexter&star.
Rivinus ducts SYN: minor sublingual ducts.
saccular d. [TA] saccular portion of the utriculosaccular d.; extends between the sacculus and the endolymphatic d.. SEE ALSO: utriculosaccular d.. SYN: ductus saccularis [TA] .
salivary d. SYN: striated d..
Santorini d. SYN: accessory pancreatic d..
Schüller ducts SYN: paraurethral ducts.
secretory d. SYN: striated d..
semicircular ducts [TA] three small membranous tubes in the bony semicircular canals that lie within the bony labyrinth and form loops of about two-thirds of a circle. The three semicircular ducts: anterior semicircular d. [TA] (ductus semicircularis anterior [TA]), lateral semicircular d. [TA] (ductus semicircularis lateralis [TA]), and posterior semicircular d. [TA] (ductus semicircularis posterior [TA]), lie in planes at right angles to each other and open into the vestibule by five openings of which one is common to the anterior and lateral ducts. Each d. has an ampulla at one end within which filaments of the vestibular nerve terminate. SYN: ductus semicirculares [TA] .
seminal d. any one of the ducts conveying semen from the epididymis to the urethra, ductus deferens, or ejaculatory d.. SYN: gonaduct (1) .
ducts of Skene glands SYN: paraurethral ducts.
spermatic d. SYN: ductus deferens.
Stensen d., Steno d. SYN: parotid d..
striated d. a type of intralobular d. found in some salivary glands that modifies the secretory product; it derives its name from extensive infolding of the basal membrane. SYN: salivary d., secretory d..
subclavian d. SYN: subclavian lymphatic trunk.
submandibular d. [TA] the d. of the submandibular salivary gland; it opens at the sublingual papilla near the frenulum of the tongue. SYN: ductus submandibularis [TA] , ductus submaxillaris, submaxillary d., Wharton d..
submaxillary d. SYN: submandibular d..
sudoriferous d. SYN: d. of sweat glands.
sweat d. SYN: d. of sweat glands.
d. of sweat glands the superficial portion of the sweat gland that passes through the corium and epidermis, opening on the surface by the porus sudoriferus or sweat pore. SYN: ductus sudoriferus, sudoriferous d., sweat d..
testicular d. SYN: ductus deferens.
thoracic d. [TA] the largest lymph vessel in the body, beginning at the cisterna chyli at about the level of the second lumbar vertebra; the abdominal part extends superiorly to pass through the aortic opening of the diaphragm, where it becomes the thoracic part and crosses the posterior mediastinum to form the arch of the thoracic d. and discharge into the left venous angle (origin of the brachiocephalic vein). SYN: ductus thoracicus [TA] , Pecquet d., van Horne canal.
thyroglossal d. [TA] a transitory endodermal tube in the embryo, carrying thyroid-forming tissue at its caudal end; normally, the d. disappears after the thyroid has moved to its definitive location in the neck; its point of origin is regularly marked on the root of the adult tongue by the foramen cecum; occasionally, its incomplete regression results in the formation of cysts along its embryonic course. SEE ALSO: pyramidal lobe of thyroid gland. SYN: ductus thyroglossus [TA] , thyrolingual d..
thyrolingual d. SYN: thyroglossal d..
umbilical d. SYN: yolk stalk.
uniting d. SYN: ductus reuniens.
utricular d. [TA] utricular portion of the utriculosaccular d.; extends between the utriculus and the endolymphatic d.. SEE ALSO: utriculosaccular d.. SYN: ductus utricularis [TA] .
utriculosaccular d. [TA] a d. that connects the inner aspect of the utricle with the endolymphatic d. a short distance from its origin from the saccule. SYN: ductus utriculosaccularis [TA] , Böttcher canal.
vitelline d., vitellointestinal d. SYN: yolk stalk.
Walther ducts SYN: minor sublingual ducts.
Wharton d. SYN: submandibular d..
Wirsung d. SYN: pancreatic d..
wolffian d. SYN: mesonephric d..

ductal
ductal (duk′tal)

Relating to a duct.

ductile
ductile (duk′til)

Denoting the property of a material that allows it to be bent, drawn out (as a wire), or otherwise deformed without breaking. [L. ductilis, capable of being led or drawn]

duction
duction (duk′shun)

1. The act of leading, bringing, conducting. 2. In ophthalmology, ocular rotations with reference to one eye; usually additionally designating direction of movement of the eye; e.g., rotation toward the nose, adduction; toward the temple, abduction; upward, supra- or sursumduction; downward, deorsumduction; of the upper pole of one cornea, cycloduction; of the upper pole of one cornea outward, excycloduction; of the upper pole of one cornea inward, incycloduction. [L. duco, to lead]
forced d. a maneuver to determine whether a mechanical obstruction is present in the eye; with forceps grasping an eye muscle, an attempt is made to passively move the eyeball in the direction of restricted rotation. SYN: passive d..
passive d. SYN: forced d..

ductless
ductless (dukt′les)

Having no duct; denoting certain glands having only an internal secretion.

ductular
ductular (duk′too-lar)

Relating to a ductule.

ductule
ductule (duk′tool)

A minute duct. SYN: ductulus.
aberrant ductules [TA] the superior or inferior diverticula of the epididymis. SYN: ductuli aberrantes [TA] , aberrant ducts, ductus aberrantes, vasa aberrantia.
biliary ductules the excretory ducts of the liver that connect the interlobular ductules to the right (or left) hepatic duct. SYN: canalicular ducts (2) , ductuli biliferi, ductus biliferi, tubuli biliferi.
efferent ductules of testis [TA] 12–14 small seminal ducts leading from the testis to the head of the epididymis. SYN: ductuli efferentes testis [TA] , efferent duct, vas efferens (3) .
excretory ductules of lacrimal gland SYN: excretory ducts of lacrimal gland, under duct.
inferior aberrant d. [TA] a narrow, coiled tubule frequently connected to the first part of the ductus deferens or to the lower part of the ductus epididymitis. SYN: ductulus aberrans inferior [TA] , Haller vas aberrans.
interlobular ductules bile ductules occupying portal canals between hepatic lobules that open into the ductuli biliferi. SYN: ductuli interlobulares.
prostatic ductules [TA] about 20 minute canals that receive the prostatic secretion from the glandular tubules and discharge it through openings on either side of the urethral crest in the posterior wall of the urethra. SYN: ductuli prostatici [TA] , ductus prostatici, prostatic ducts.
superior aberrant d. [TA] a diverticulum from the head of the epididymis. SYN: ductulus aberrans superior [TA] .
transverse ductules of epoöphoron [TA] a series of 10–15 short tubules that open into the longitudinal duct of the epoöphoron and represent vestiges of the mesonephric duct. SYN: ductuli transversi epoöphori [TA] , tubuli epoöphori.

ductulus
ductulus, pl .ductuli (duk′too-lus, -too-li)

SYN: ductule. [Mod. L. dim. of L. ductus, duct]
d. aberrans inferior [TA] SYN: inferior aberrant ductule.
d. aberrans superior [TA] SYN: superior aberrant ductule.
ductuli aberrantes [TA] SYN: aberrant ductules, under ductule.
d. alveolaris, pl .ductuli alveolares SYN: alveolar duct.
ductuli biliferi SYN: biliary ductules, under ductule.
ductuli efferentes testis [TA] SYN: efferent ductules of testis, under ductule.
ductuli excretorii glandulae lacrimalis SYN: excretory ducts of lacrimal gland, under duct.
ductuli interlobulares SYN: interlobular ductules, under ductule.
ductuli paroöphori tubular remnants of the embryonic mesonephros forming the paroöphoron. SYN: tubuli paroöphori.
ductuli prostatici [TA] SYN: prostatic ductules, under ductule.
ductuli transversi epoöphori [TA] SYN: transverse ductules of epoöphoron, under ductule. SEE ALSO: epoophoron.

ductus
ductus, gen. and pl. ductus (duk′tus) [TA]

SYN: duct. [L. a leading, fr. duco, pp. d., to lead]
d. aberrantes SYN: aberrant ductules, under ductule.
d. arteriosus a fetal vessel connecting the left pulmonary artery with the descending aorta; in the first two months after birth, it normally changes into a fibrous cord, the ligamentum arteriosum; persistent postnatal patentcy is a correctable cardiovascular handicap. SYN: arterial canal, arterial duct, Botallo duct.
d. biliaris [TA] SYN: bile duct (2) .
d. biliferi SYN: biliary ductules, under ductule.
d. caroticus a portion of the embryonic dorsal aorta between points of juncture with the third and fourth arch arteries; it disappears early in development. SYN: carotid duct.
d. choledochus [TA] SYN: bile duct (1) .
d. cochlearis [TA] SYN: cochlear duct.
d. cysticus [TA] SYN: cystic duct.
d. deferens [TA] the secretory duct of the testicle, running from the epididymis, of which it is the continuation, to the prostatic urethra where it terminates as the ejaculatory duct. SYN: deferent canal, deferent duct, spermatic duct, spermiduct (1) , testicular duct, vas deferens.
d. deferens vestigialis SYN: longitudinal duct of epoöphoron.
d. diverticulum SYN: ductal aneurysm.
d. dorsopancreaticus SYN: accessory pancreatic duct.
d. ejaculatorius [TA] SYN: ejaculatory duct.
d. endolymphaticus [TA] SYN: endolymphatic duct.
d. epididymidis [TA] SYN: duct of epididymis.
d. excretorius SYN: excretory duct.
d. excretorius glandulae vesiculosae [TA]
d. excretorius vesiculae seminalis [TA] SYN: excretory duct of seminal gland.
d. glandulae bulbourethralis [TA] SYN: duct of bulbourethral gland.
d. hemithoracicus SYN: hemithoracic duct.
d. hepaticus communis [TA] SYN: common hepatic duct.
d. hepaticus dexter [TA] SYN: right hepatic duct.
d. hepaticus sinister [TA] SYN: left hepatic duct.
d. incisivus [TA] SYN: incisive duct.
d. lactiferi [TA] SYN: lactiferous ducts, under duct.
d. lingualis a pit on the upper surface of the tongue at the apex of the sulcus terminalis; it marks the point of origin of the d. thyroglossus of the embryo; known more commonly as the foramen cecum.
d. lobi caudati dexter hepatis [TA] SYN: right duct of caudate lobe of liver.
d. lobi caudati sinister hepatis [TA] SYN: left duct of caudate lobe of liver.
d. longitudinalis epoöphori [TA] SYN: longitudinal duct of epoöphoron. SEE ALSO: epoophoron.
d. lymphaticus dexter [TA] SYN: right lymphatic duct.
d. mesonephricus SYN: mesonephric duct. SEE ALSO: longitudinal duct of epoöphoron.
d. nasolacrimalis [TA] SYN: nasolacrimal duct.
d. pancreaticus [TA] SYN: pancreatic duct.
d. pancreaticus accessorius [TA] SYN: accessory pancreatic duct.
d. paramesonephricus SYN: paramesonephric duct.
d. paraurethrales [TA] SYN: paraurethral ducts, under duct.
d. parotideus [TA] SYN: parotid duct.
patent d. arteriosus d. arteriosus.
d. perilymphaticus SYN: cochlear aqueduct.
d. pharyngobranchialis III a narrow communication between the third branchial pouch and the pharynx in the embryo.
d. pharyngobranchialis IV a narrow communication between the fourth branchial pouch and the pharynx in the embryo.
d. prostatici SYN: prostatic ductules, under ductule.
d. reuniens [TA] a short membranous tube passing from the lower end of the saccule to the cochlear duct of the membranous labyrinth. SYN: canaliculus reuniens, canalis reuniens, Hensen canal, Hensen duct, uniting canal, uniting duct.
d. saccularis [TA] SYN: saccular duct.
d. semicirculares [TA] SYN: semicircular ducts, under duct.
d. sublinguales minores [TA] SYN: minor sublingual ducts, under duct.
d. sublingualis major [TA] SYN: major sublingual duct.
d. submandibularis [TA] SYN: submandibular duct.
d. submaxillaris SYN: submandibular duct.
d. sudoriferus SYN: duct of sweat glands.
d. thoracicus [TA] SYN: thoracic duct.
d. thoracicus dexter right lymphatic duct.
d. thyroglossus [TA] SYN: thyroglossal duct.
d. utricularis [TA] SYN: utricular duct.
d. utriculosaccularis [TA] SYN: utriculosaccular duct.
d. venosus in the fetus, continuation of the left umbilical vein through the liver to the vena cava inferior; after birth, its lumen becomes obliterated, forming the ligamentum venosum.
d. venosus arantii rarely used term for d. venosus.

Duddell
Duddell

Benedict, 18th century British oculist. See D. membrane.

Duffy blood group
Duffy blood group

See Blood Groups appendix.

Dugas
Dugas

Louis A., U.S. physician, 1806–1884.

Duhring
Duhring

Louis A., U.S. dermatologist, 1845–1913. See D. disease.

Dührssen
Dührssen

Alfred, German obstetrician-gynecologist, 1862–1933. See D. incisions, under incision.

Duke
Duke

William Waddell D., U.S. pathologist, 1883–1945. See D. bleeding time test.

Dukes
Dukes

Clement, English physician, 1845–1925. See D. disease, Filatov-D. disease.

Dukes
Dukes

Cuthbert E., British pathologist, 1890–1977. See D. classification.

dulcin
dulcin (dul′sin)

Has been used as a substitute for sugar, being 200 times as sweet as cane sugar. Because of hydrolysis to aminophenol, it may produce an injurious effect when used over long periods of time.

dulcite
dulcite, dulcitol, dulcose (dul′sit, -si′tol, -kos)

Galactitol.

dull
dull (dul)

Not sharp or acute, in any sense; qualifying a surgical instrument, the action of the mind, pain, a sound (especially the percussion note), etc. [M.E. dul]

dullness
dullness, dulness (dul′nes)

The character of the sound obtained by percussing over a solid part incapable of resonating; usually applied to an area containing less air than those which can resonate.
shifting d. a sign of free peritoneal fluid wherein the d. of percussion shifts, generally from one side to the other, as the patient is turned from side to side.

Dulong
Dulong

Pierre L., French chemist, 1785–1838. See D.-Petit law.

dummy
dummy (dum′e)

SYN: pontic.

Dumontpallier
Dumontpallier

Alphonse, French physician, 1827–1899. See D. pessary.

dumping
dumping (dump′ing)

See d. syndrome.

Duncan
Duncan

James M., Scottish gynecologist, 1826–1890. See D. folds, under fold, D. mechanism, D. placenta, D. ventricle.

Duncan Duncan

Surname of first studied patients afflicted with what is now known as D. disease.

Dunn
Dunn

Richard L. See Lison-D. stain.

duocrinin
duocrinin (doo-o-krin′in)

A postulated gastrointestinal hormone that is liberated by the contact of gastric contents with the intestine and that stimulates the secretory activity of the duodenal glands (Brunner glands). [duodenum + G. krino, to secrete, + -in]

duodenal
duodenal (doo′o-de′nal, doo-od′e-nal)

Relating to the duodenum.

duodenectomy
duodenectomy (doo-o-de-nek′to-me)

Excision of the duodenum. [duodenum + G. ektome, excision]

duodenitis
duodenitis (doo-od-e-ni′tis)

Inflammation of the duodenum.

duodeno- duodeno-

Combining form relating to the duodenum. [L. duodenum, scil., digitorum breadth of 12 fingers]

duodenocholangitis
duodenocholangitis (doo-o-de′no-ko-lan-ji′tis)

Inflammation of the duodenum and common bile duct. [duodeno- + G. chole, bile, + angeion, vessel, + -itis, inflammation]

duodenocholecystostomy
duodenocholecystostomy (doo-o-de′no-ko-le-sis-tos′to-me)

SYN: cholecystoduodenostomy. [duodeno- + G. chole, bile, + kystis, bladder, + stoma, mouth]

duodenocholedochotomy
duodenocholedochotomy (doo-o-de′no-ko-led-o-kot′o-me)

Incision into the common bile duct and the adjacent portion of the duodenum. [duodeno- + G. cholèdochus, bile duct, + tome, incision]

duodenocystostomy
duodenocystostomy (doo-o-de′no-sis-tos′to-me)

1. SYN: cholecystoduodenostomy. 2. SYN: cystoduodenostomy. 3. SYN: pancreatic cystoduodenostomy.

duodenoenterostomy
duodenoenterostomy (doo-o-de′no-en-ter-os′to-me)

Establishment of communication between the duodenum and another part of the intestinal tract. [duodeno- + G. enteron, intestine, + stoma, mouth]

duodenojejunostomy
duodenojejunostomy (doo-o-de′no-je-joo-nos′to-me)

Operative formation of an artificial communication between the duodenum and the jejunum. [duodeno- + jejunum, + G. stoma, mouth]

duodenolysis
duodenolysis (doo-o-de-nol′i-sis)

Incision of adhesions to the duodenum. [duodeno- + G. lysis, a freeing]

duodenorrhaphy
duodenorrhaphy (doo-o-de-nor′a-fe)

Suture of a tear or incision in the duodenum. [duodeno- + G. rhaphe, a seam]

duodenoscopy
duodenoscopy (doo-o-de-nos′ko-pe)

Inspection of the interior of the duodenum through an endoscope. [duodeno- + G. skopeo, to examine]

duodenostomy
duodenostomy (doo-o-de-nos′to-me)

Establishment of a fistula into the duodenum. [duodeno- + G. stoma, mouth]

duodenotomy
duodenotomy (doo-o-de-not′o-me)

Incision of the duodenum. [duodeno- + G. tome, incision]

duodenum
duodenum, gen. duodeni, pl .duodena (doo-o-de′num, doo-od′e-num; -od′e-na, -de′na) [TA]

The first division of the small intestine, about 25 cm or 12 fingerbreadths (hence the name) in length, extending from the pylorus to the junction with the jejunum at the level of the first or second lumbar vertebra on the left side. It is divided into the superior part, the first part of which is the duodenal cap, the descending part, into which the bile and pancreatic ducts open, the horizontal (inferior) part and the ascending part, terminating at the duodenojejunal junction. [Mediev. L. fr. L. duodeni, twelve]

duovirus
duovirus (doo′o-vi′rus)

SYN: rotavirus.

duplex
duplex (doo′pleks)

Providing two functions. See d. ultrasonography.

duplication
duplication (doo-pli-ka′shun)

1. A doubling. SEE ALSO: reduplication. 2. Inclusion of two copies of the same genetic material in a genome; an important step in diversification of genomes, as in the evolution of the (nonallelic) hemoglobin chains from a common ancestor. SYN: gene d.. [L. duplicatio, a doubling, fr. duplico, to double]
d. of chromosomes a chromosome aberration resulting from unequal crossing over or exchange of segments between two homologous chromosomes; one chromosome of the pair loses a small segment, while the other gains this segment; the chromosome gaining the segment has undergone d. while its homologue has undergone deletion. See hemoglobin Lepore.
gene d. SYN: d. (2) .

duplicitas
duplicitas (doo-plis′i-tahs)

Doubling of a part. [L. a doubling, fr. duplex (duplic-), two-fold]
d. anterior conjoined twins in which there are two thoraces and two heads and a single pelvis with one pair of lower extremities. See conjoined twins, under twin. SEE ALSO: cephalodidymus, ileadelphus, iliadelphus. SYN: catadidymus.
d. posterior conjoined twins in which there is a single head and upper body and duplicated buttocks and legs. See conjoined twins, under twin. SEE ALSO: dipygus. SYN: anadidymus, ileadelphus, iliadelphus.

Dupré
Dupré

17th Century Paris surgeon and anatomist. See Dupré muscle.

Dupuytren
Dupuytren

Baron Guillaume, French surgeon and surgical pathologist, 1777–1835. See D. amputation, D. canal, D. contracture, D. disease of the foot, D. fascia, D. fracture, D. hydrocele, D. sign, D. suture, D. tourniquet.

dura
dura (doo′ra) [TA]

SYN: d. mater. [L. fem. of durus, hard]
d. mater cranialis [TA] SYN: cranial d. mater.

duraencephalosynangiosis
duraencephalosynangiosis (door′a-en-sef′a-lo-sin-anj-e- o′sis)

Surgical transposition of the superficial temporal artery with attached galea to the underlying dura with hope for cerebral revascularization; most commonly used in moyamoya syndrome. SYN: encephaloduroarteriosynangiosis.

dural
dural (doo′ral)

Relating to the dura mater. SYN: duramatral.

dura mater
dura mater (doo′ra ma′ter) [TA]

Pachymeninx (as distinguished from leptomeninx, the combined pia mater and arachnoid); a tough, fibrous membrane forming the outer covering of the central nervous system. SYN: dura [TA] , pachymeninx [TA] . [L. hard mother, mistransl. of Ar. umm al-jafiyah, tough protector or covering]
d. of brain SYN: cranial d..
cranial d. [TA] the intracranial d., consisting of two layers: the outer periosteal layer that normally always adheres to the periosteum of the bones of the cranial vault; and the inner meningeal layer that in most places is fused with the outer. The two layers separate to accommodate meningeal vessels and large venous (dural) sinuses. The meningeal layer is also involved in the formation of the various dural folds, such as the falx cerebri and tentorium cerebelli and is comparable to and continuous with the dural mater of the spinal cord. The cranial epidural space is then an artifactual space between the bone and the combined periosteum/periosteal layer of the d. realized only as a result of pathologic or traumatic processes and is neither continuous with or comparable to the vertebral epidural space. SYN: dura mater cranialis [TA] , d. encephali&star, cerebral part of d., d. of brain.
d. encephali cranial d..
spinal d. [TA] single-layered strong membrane, comparable to and continuous with (at foramen magnum) the meningeal layer of the intracranial d. of the brain. It does not (in contrast to the d. of brain) adhere to the enveloping bony structures (vertebrae) or their periosteum, being separated from the latter by a considerable space, the vertebral epidural space—a true space containing the internal vertebral venous plexus embedded in a matrix of epidural fat. SYN: d. spinalis [TA] , d. of spinal cord, endorrhachis, theca vertebralis.
d. of spinal cord SYN: spinal d..
d. spinalis [TA] SYN: spinal d..

duramatral
duramatral (doo-ra-ma′tral)

SYN: dural.

Duran-Reynals
Duran-Reynals

Francisco, U.S. bacteriologist, 1899–1958. See Duran-Reynals permeability factor.

duraplasty
duraplasty (doo′ra-plas-te)

A reconstructive operation on the open dura mater that involves a primary closure or secondary closure with another soft tissue material ( e.g., muscle, fascia, allograft dura). [dura (mater) + G. plastos, formed]

duration
duration (D) (doo-ra′shun)

A continuous period of time.
half amplitude pulse d. the time, in milliseconds, required for a wave form to reach half of its full magnitude.
pulse wave d. the interval between onset of the leading edge and the end of the trailing edge of a pulse wave.

Dürck
Dürck

Hermann, German pathologist, 1869–1941. See D. nodes, under node.

dur. dolor.
dur. dolor.

Abbreviation for L. duarte dolare, while pain lasts.

Duret
Duret

Henri, French neurosurgeon, 1849–1921. See D. lesion, D. hemorrhage.

Durham
Durham

Arthur E., English surgeon, 1834–1895. See D. tube.

Duroziez
Duroziez

Paul L., French physician, 1826–1897. See D. disease, D. murmur, D. sign.

DUSN
DUSN

Acronym for diffuse unilateral subacute neuroretinitis.

dUTP
dUTP

Abbreviation for deoxyuridine 5-triphosphate.

Dutton
Dutton

Joseph Everett, English physician, 1877–1905. See D. disease, D. relapsing fever.

Duverney
Duverney

Guichaud Joseph, French anatomist, 1648–1730. See D. fissures, under fissure, D. gland, D. muscle.

dwarf
dwarf (dworf)

An abnormally undersized person with disproportion among the bodily parts. See dwarfism. [A.S. dweorh]
hypophysial d. dwarfism as result of failure of growth hormone production because of hypothalamic or pituitary abnormality. SYN: pituitary d..
hypothyroid d. dwarfism associated with lack of thyroid function.
pituitary d. SYN: hypophysial d..

dwarfism
dwarfism (dworf′izm)

A condition or a group of conditions in which the standing height of the person is below the 3rd percentile.
achondroplastic d. achondroplasia.
acromelic d. SYN: acromesomelic d..
acromesomelic d. a form of short-limb d. characterized by pug-nose and shortening particularly striking in the distal segment of the limbs, i.e., the forearms and lower legs, fingers and toes; autosomal recessive inheritance. SYN: acromelic d., acromesomelia.
aortic d. underdevelopment of physical stature associated with severe aortic stenosis.
asexual d. d. in which adult sexual development is deficient.
ateliotic d. SYN: panhypopituitarism.
camptomelic d. d. with shortening of the lower limbs due to anterior bending of the femur and tibia.
chondrodystrophic d. chondrodystrophy.
deprivation d. short stature due to emotional deprivation. SYN: psychosocial d..
diastrophic d. [MIM*222600] SYN: diastrophic dysplasia.
disproportionate d. d. characterized by more significant shortening of the limbs or the trunk; when the limbs are primarily involved, the shortening may predominate in the proximal segments (rhizomelia), middle segments (mesomelia), or distal segments (acromelia); usually results from hereditary intrinsic skeletal dysplasias.
Fröhlich d. d. with Fröhlich syndrome.
Hunter-Thompson d. [MIM*201250] a severe form of acromesomelic d., characterized by shortening of the distal segments of the limbs; lower extremities are more severely affected than the upper limbs; often associated with dislocations of elbows, knees, and hips. Autosomal recessive inheritance, caused by mutations in the cartilage-derived morphogenetic protein 1 (CDMP1) gene on chromosome 20q.
hypothyroid d. SYN: infantile hypothyroidism.
infantile d. SYN: infantilism (1) .
Laron type d. d. associated with an absent or very low levels of somatomedin C (insulinlike growth factor I) or abnormalities in receptor activity.
lethal d. d. leading to intrauterine or neonatal death.
Lorain-Lévi d. SYN: pituitary d..
mesomelic d. d. with shortness of the forearms and lower legs.
metatropic d. [MIM*250600] a skeletal dysplasia characterized by disproportionate d. in which the trunk is long relative to the limbs at birth but undergoes reversal of this proportion with subsequent development with severe and progressive kyphoscoliosis; there is metaphyseal flare of long bones, the pelvis is halberd-shaped, and the coccyx is long, resulting in a sacral appendage; autosomal recessive inheritance.
micromelic d. d. with abnormally short or small limbs.
panhypopituitary d. type I is an autosomal recessive disorder with deficient human growth hormone, ACTH, FSH, etc., having delayed sexual development, hypothyroidism, and adrenal insufficiency; type II is similar but is an X-linked disorder.
phocomelic d. d. in which the diaphyses of the long bones are abnormally short or the intermediate parts of the limbs are absent.
physiologic d. d. characterized by normal development that is at a strikingly lesser rate than that for members of the same family, race, or other races. SYN: primordial d., true d..
pituitary d. a rare form of d. caused by the absence of a functional anterior pituitary gland; may be present at birth or develop during early childhood. SYN: Lorain-Lévi d., Lorain-Lévi infantilism, Lorain-Lévi syndrome, pituitary infantilism.
primordial d. SYN: physiologic d..
proportionate d. d. characterized by a symmetric shortening of the limbs and trunk; generally results from chemical, endocrine, nutritional, or nonosseous abnormalities.
psychosocial d. SYN: deprivation d..
rhizomelic d. one of the syndromes of chondrodysplasia punctata (q.v.), autosomal recessive, with variable skin keratinization disorders and variable facial, cardiac, optic, and central nervous system abnormalities; epiphyseal stippling is also present. There are multiple enzymatic defects, including peroxisomal ones, and affected infants fail to thrive and usually die in infancy.
Robinow d. SYN: Robinow syndrome.
Seckel d. SYN: Seckel syndrome.
senile d. d. characterized by craniofacial anomalies with progeroid appearance.
sexual d. d. with normal sexual development.
Silver-Russell d. SYN: Silver-Russell syndrome.
snub-nose d. [MIM*127100] d. characterized by low birth weight, snub nose, and stocky build; autosomal dominant inheritance. There is a similar autosomal recessive phenotype [MIM*223600]. SYN: dominantly inherited Lévi disease.
thanatophoric d. a lethal d. characterized by micromelia, bowed long bones, enlarged head, flattened vertebral bodies, and muscular hypotonia; lack of pulmonary ventilation causes respiratory difficulties with cyanosis leading to death within the first few hours or days after birth.
true d. SYN: physiologic d..

Dwyer
Dwyer

Frederick, English orthopaedic surgeon, 1920–1975. See D. osteotomy.

Dy
Dy

Symbol for dysprosium.

dyad
dyad (di′ad)

1. A pair. SYN: diad (2) . 2. In chemistry, a bivalent element. 3. A pair of persons in an interactional situation, e.g., patient and therapist, husband and wife. 4. The double chromosome resulting from the splitting of a tetrad during meiosis. 5. Two units treated as one. 6. A pair of cells resulting from the first meitotic division. [G. dyas, the number two, duality]

dyclonine hydrochloride
dyclonine hydrochloride (di′klo-nen)

A topical local anesthetic.

dydrogesterone
dydrogesterone (di-dro-jes′ter-on)

A synthetic steroid, derived from retroprogesterone, with progestational effects.

dye
dye (di)

A stain or coloring matter; a compound consisting of chromophore and auxochrome groups attached to one or more benzene rings, its color being due to the chromophore and its dyeing affinities to the auxochrome. Dyes are used for intravital coloration of living cells, staining tissues and microorganisms, as antiseptics and germicides, and some as stimulants of epithelial growth. For individual dyes, see the specific names. Commonly but improperly used for radiographic contrast medium. [A.S. deah, deag]
acidic dyes dyes that ionize in solution to produce negatively charged ions or anions; they consist of sodium salts of phenols and carboxylic acid dyes; their solutions tend to be neutral or slightly alkaline; examples are eosin and aniline blue.
acridine dyes derivatives of the compound acridine that is closely related to xanthene; important as fluorochromes in histology, cytochemistry, and chemotherapy; examples include acriflavine, acridine orange, and quinacrine mustard.
azin dyes d. derivatives of phenazine that include important histologic stains, such as neutral red, azocarmine G., and safranin O.
azo dyes dyes in which the azo group is the chromophore and joins benzene or naphthalene rings; they include a large number of biologic stains, such as Congo red and oil red O; also used clinically to promote epithelial growth in the treatment of ulcers, burns, and other wounds; many have anticoagulant action.
azocarmine dyes dyes giving a dark purplish red color as histologic stains.
basic dyes dyes which ionize in solution to give positively charged ions or cations; the auxochrome group is an amine which can form a salt with an acid like HCl; solutions are usually slightly acidic; examples include basic fuchsin and toluidine blue O.
chlorotriazine dyes dyes containing one or more chlorotriazine moieties that react with polysaccharides.
diphenylmethane dyes dyes in which the central carbon connecting two phenyl groups lacks an amino or imino group; the chromophore is the quinoid ring; an alternative formulation is as a ketonimide; the most common example is auramine O.
ketonimine dyes dyes in which the chromophore is &bivbond;C&dbond;NH connected to two benzene rings; alkylamino groups are added para to the methane carbon on both rings. The most important member for biological purposes is auramine O; an alternative formulation is as a diphenylmethane d..
natural dyes dyes obtained from animals or plants; examples include carmine, obtained from cochineal in the dried female insect Dactylopius coccus of Central America, and hematoxylin, extracted from the bark of the logwood tree Haematoxylon campechianum in the Caribbean area.
nitro dyes dyes in which the chromophore is &cbond;NO₂, which is so acidic that all dyes in this group are of the acid type; important examples in cytoplasmic staining are picric acid and naphthol yellow S.
oxazin dyes similar to azin dyes except that one of the connecting N atoms is replaced by O; most important representatives are brilliant cresyl blue, orcein, litmus, and cresyl violet.
rosanilin dyes several triaminotriphenylmethane dyes or mixtures of them often sold under the name of basic fuchsin; rosanilin dyes differ from other triphenylmethane dyes in that the amino groups are unsubstituted, and they may have methyl groups introduced directly onto the benzene rings; the four possible such dyes are pararosanilin, rosanilin, new fuchsin, and magenta II.
salt d. SYN: neutral stain.
synthetic dyes organic d. compounds originally derived from coal-tar derivatives; presently produced by synthesis from benzene and its derivatives; examples include eosin, methylene blue, and fluorescein.
thiazin dyes similar to azin dyes except that one of the connecting N atoms is replaced by S; includes many important biologic stains, especially in hematology, e.g., azure A, azure B, and methylene blue.
triphenylmethane dyes a group of dyes that includes pararosanilin, as well as many others used in histology and cytology; employed as nuclear, cytoplasmic, and connective tissue stains; important in histochemistry as in the preparation of Schiff reagent.
xanthene dyes derivatives of the compound xanthene; include the pyronins, rhodamines, and fluoresceins.

Dyggve
Dyggve

Holger, Danish pediatrician, 1913–1984. See D.-Melchior-Clausen syndrome.

-dymus -dymus

1. Suffix to be combined with number roots; e.g., didymus, tridymus, tetradymus. 2. Occasionally used shortened form for -didymus. [G. -dymos, fold]

dynamics
dynamics (di-nam′iks)

1. The science of motion in response to forces. 2. In psychiatry, used as a contraction of psychodynamics. 3. In the behavioral sciences, any of the numerous intrapersonal and interpersonal influences or phenomena associated with personality development and interpersonal processes. [G. dynamis, force]
group d. a term used to represent the study of underlying features of group behavior, e.g., motives, attitudes; it is concerned with group change rather than with static characteristics.

dynamo- dynamo-

Combining form denoting force, energy. [G. dynamis, power]

dynamogenesis
dynamogenesis (di′na-mo-jen′e-sis)

The production of force, especially of muscular or nervous energy. SYN: dynamogeny. [dynamo- + G. genesis, production]

dynamogenic
dynamogenic (di′na-mo-jen′ik)

Producing power or force, especially nervous or muscular power or activity.

dynamogeny
dynamogeny (di-na-moj′e-ne)

SYN: dynamogenesis.

dynamograph
dynamograph (di-nam′o-graf)

An instrument for recording the degree of muscular power. [dynamo- + G. grapho, to write]

dynamometer
dynamometer (di-na-mom′e-ter)

An instrument for measuring the degree of muscular power. SYN: ergometer. [dynamo- + G. metron, measure]

dynamoscope
dynamoscope (di-nam′o-skop)

A modified stethoscope for auscultation of the muscles. [dynamo- + G. skopeo, to examine]

dynamoscopy
dynamoscopy (di-na-mos′ko-pe)

Auscultation of a contracting muscle.

dynatherm
dynatherm (di′na-therm)

An apparatus for inducing diathermy. [G. dynamis, force, + therme, heat]

dyne
dyne (din)

The unit of force in the CGS system, replaced in the SI system by the newton (1 N = 10⁵ dynes), that gives a body of 1 g mass an acceleration of 1 cm/sec²; expressed as F (dynes) = m (grams) × a (cm/sec²). [G. dynamis, force]

dynein
dynein (din′en)

A protein associated with motile structures, exhibiting adenosine triphosphatase activity; it forms “arms” on the outer tubules of cilia and flagella. It functions as a molecular motor. SEE ALSO: tubulin, d. arm. [dyne + protein]

dynorphin
dynorphin (di′nor-fin)

An endogenous opioid ligand that acts as an agonist at opiate receptors. Extremely potent, widely distributed neuropeptide that has 17 amino acid residues and contains leu⁵-enkephalin as its NH₂-terminal sequence.

dyphylline
dyphylline (di-fil′in)

Exhibits characteristic peripheral vasodilator and bronchodilator actions of other theophylline compounds.

dys- dys-

Bad, difficult, un-, mis-; opposite of eu-. Cf.:dis-. [G.]

dysacousia
dysacousia, dysacusia (dis-a-ku′se-a)

SYN: dysacusis.

dysacusis
dysacusis (dis-a-ku′sis)

1. Any impairment of hearing involving difficulty in processing details of sound as opposed to any loss of sensitivity to sound. 2. Pain or discomfort in the ear from exposure to sound. SYN: dysacousia, dysacusia. [dys- + G. akousis, hearing]

dysadaptation
dysadaptation (dis′ad-ap-ta′shun)

Inability of the retina and iris to accommodate well to varying intensities of light.

dysantigraphia
dysantigraphia (dis′an-te-graf′e-a)

A form of agraphia in which the subject is unable to copy written or printed matter. [dys- + G. antigrapho, to write back]

dysaphia
dysaphia (dis-a′fe-a, dis-af′e-a)

Impairment of the sense of touch. [dys- + G. haphe, touch]

dysaphic
dysaphic (dis-a′fik)

Relating to impaired tactile sensibility.

dysarteriotony
dysarteriotony (dis-ar-ter-e-ot′o-ne)

Abnormal blood pressure, either too high or too low. [dys- + G. arteria, artery, + tonos, tension]

dysarthria
dysarthria (dis-ar′thre-a)

A disturbance of speech due to emotional stress, to brain injury, or to paralysis, incoordination, or spasticity of the muscles used for speaking. SYN: dysarthrosis (1) . [dys- + G. arthroo, to articulate]
ataxic d. d. caused by cerebellar lesions.
hyperkinetic d. d. caused by chorea and myoclonus.
hypokinetic d. d. caused by the rigid types of extrapyramidal disease.
lower motor neuron d. d. caused by dysfunction of the motor nuclei and the lower pons or medulla, or other neural connections, central and peripheral to the muscles of articulation.
rigid d. SYN: spastic d..
spastic d. d. caused by lesions along the corticobulbar tracts. SYN: rigid d..

dysarthric
dysarthric (dis-ar′thrik)

Relating to dysarthria.

dysarthrosis
dysarthrosis (dis-ar-thro′sis)

1. SYN: dysarthria. 2. Malformation of a joint. 3. A false joint. [dys- + G. arthrosis, joint]

dysautonomia
dysautonomia (dis′aw-to-no′me-a)

Abnormal functioning of the autonomic nervous system. [dys- + G. autonomia, self-government]
familial d. [MIM*223900] a congenital syndrome with specific disturbances of the nervous system and aberrations in autonomic nervous system function such as indifference to pain, diminished lacrimation, poor vasomotor homeostasis, motor incoordination, labile cardiovascular reactions, hyporeflexia, frequent attacks of bronchial pneumonia, hypersalivation with aspiration and difficulty in swallowing, hyperemesis, emotional instability, and an intolerance for anesthetics; autosomal recessive inheritance. Mapped to human chromosome 9q31–q33. SYN: Riley-Day syndrome.

dysbarism
dysbarism (dis′bar-izm)

General term for the symptom complex resulting from exposure to decreased or changing barometric pressure, including all physiologic effects resulting from such changes with the exception of hypoxia, and including the effects of rapid decompression. [dys- + G. baros, weight]

dysbasia
dysbasia (dis-ba′ze-a)

1. Difficulty in walking. 2. The difficult or distorted walking that occurs in persons with certain mental disorders. [dys- + G. basis, a step]
d. angiosclerotica, d. angiospastica obsolete terms meaning intermittent difficulty in walking due to peripheral vascular causes.
d. lordotica progressiva an affection characterized by lordoscoliosis of the lower portion of the vertebral column, occurring when the patient stands or walks and usually disappearing when the patient lies down. SYN: torsion neurosis.

dysbetalipoproteinemia
dysbetalipoproteinemia (dis-ba′ta-lip-o-pro′ten-e′me-a)

SYN: type III familial hyperlipoproteinemia.

dysbolism
dysbolism (dis′bo-lizm)

Abnormal, but not necessarily morbid, metabolism, as in alkaptonuria. [dys- + G. bole (metabole), + -ismos, metabolism]

dysbulia
dysbulia (dis-boo′le-a)

Weakness and uncertainty of volition. [dys- + G. boule, will]

dysbulic
dysbulic (dis-boo′lik)

Relating to, or characterized by, dysbulia.

dyscalculia
dyscalculia (dis-kal-ku′le-a)

Difficulty in performing simple mathematical problems; commonly seen in parietal lobe lesions. [dys- + L. calculo, to compute, fr. calculus, pebble, counter]

dyscephalia
dyscephalia (dis-se-fa′le-a)

Malformation of the head and face. SYN: dyscephaly. [dys- + G. kephale, head]
d. mandibulo-oculofacialis [MIM*234100] a syndrome of bony anomalies of the calvaria, face, and jaw, with brachygnathia, narrow curved nose, and multiple ocular defects including microphthalmia, microcornea, and cataract, often with alopecia overlying skull sutures, or alopecia areata, or absence of eyebrows. The pattern of inheritance is undecided. SYN: Hallermann-Streiff syndrome, Hallermann-Streiff-François syndrome, mandibulo-oculofacial syndrome, oculomandibulodyscephaly, oculomandibulofacial syndrome, progeria with cataract, progeria with microphthalmia.

dyscephaly
dyscephaly (dis-sef′a-le)

SYN: dyscephalia.

dyscheiral
dyscheiral, dyschiral (dis-ki′ral)

Relating to dyscheiria.

dyscheiria
dyscheiria, dyschiria (dis-ki′re-a)

A disorder of sensibility in which, although there is no apparent loss of sensation, the patient is unable to tell which side of the body has been touched (acheiria), or refers it to the wrong side (allocheiria), or to both sides (syncheiria). [dys- + G. cheir, hand]

dyschezia
dyschezia (dis-ke′ze-a)

Difficulty in defecation. [dys- + G. chezo, to defecate]

dyschondrogenesis
dyschondrogenesis (dis-kon-dro-jen′e-sis)

Abnormal development of cartilage. [dys- + G. chondros, cartilage, + genesis, production]

dyschondroplasia
dyschondroplasia (dis-kon-dro-pla′ze-a)

SYN: enchondromatosis. [dys- + G. chondros, cartilage, + plasis, a forming]
d. with hemangiomas SYN: Maffucci syndrome.

dyschondrosteosis
dyschondrosteosis (dis′kon-dros-te-o′sis) [MIM*127300]

A skeletal dysplasia, more severe in females and with a female preponderance, characterized by bowing of radius, dorsal dislocation of the distal ulna with limited movement of the elbow and wrist (wrist deformity is called Madelung deformity), and mesomelic dwarfism; dominant inheritance, caused by mutation in the short stature homeobox gene (SHOX) on the pseudoautosomal region of Xp. Langer mesomelic dysplasia, the homozygous form of d., is also caused by homozygous mutations in the SHOX gene. SYN: Leri pleonosteosis, Leri-Weill disease, Leri-Weill syndrome. [dys- + G. chondros, cartilage, + osteon, bone, + -osis, condition]

dyschroia
dyschroia, dyschroa (dis-kroy′a, -kro′a)

A bad complexion; discoloration of the skin. [dys- + G. chroia, chroa, color]

dyschromatopsia
dyschromatopsia (dis′kro-ma-top′se-a)

A condition in which the ability to perceive colors is not fully normal. Cf.:anomalous trichromatism, dichromatism, monochromatism, chromatopsia. [dys- + G. chroma, color, + opsis, vision]

dyschromatosis
dyschromatosis (dis-kro-ma-to′sis)

An asymptomatic anomaly of pigmentation occurring among the Japanese; may be localized or diffuse. [dys- + G. chroma, color, + -osis, condition]

dyschromia
dyschromia (dis-kro′me-a)

Any abnormality in the color of the skin.

dyscinesia
dyscinesia (dis′si-ne′ze-a)

SYN: dyskinesia.

dyscontrol
dyscontrol (dis-kon-trol′)

SYN: intermittent explosive disorder.

dyscoria
dyscoria (dis-ko′re-a)

Abnormality in the shape of the pupil. [dys- + G. kore, pupil of eye]

dyscrasia
dyscrasia (dis-kra′ze-a)

1. A morbid general state resulting from the presence of abnormal material in the blood, usually applied to diseases affecting blood cells or platelets. 2. Old term indicating disease. [G. bad temperament, fr. dys- + krasis, a mixing]
blood d. a diseased state of the blood; usually refers to abnormal cellular elements of a permanent character.

dyscrasic
dyscrasic, dyscratic (dis-kra′sik, krat′ik)

Pertaining to or affected with dyscrasia.

dysdiadochokinesia
dysdiadochokinesia, dysdiadochocinesia (dis-di-ad′o-ko-ki-ne′ze-a)

Impairment of the ability to perform rapidly alternating movements. [dys- + G. diadochos, working in turn, + kinesis, movement]

dysdiadochokinesis
dysdiadochokinesis (dis′di-ad-o-ko-ki-ne′sis)

SYN: adiadochokinesis.

dysemia
dysemia (dis-e′me-a)

Any abnormal condition or disease of the blood. [dys- + G. haima, blood]

dysencephalia splanchnocystica
dysencephalia splanchnocystica (dis′en-se-fa′le-a splangk-no-sis′ti-ka) [MIM*249000]

A malformation syndrome, lethal in the perinatal period, and characterized by intrauterine growth retardation, sloping forehead, occipital encephalocele, ocular anomalies, cleft palate, polydactyly, polycystic kidneys, and other malformations; autosomal recessive inheritance. Mapped to human chromosome 17q21–q24. SYN: Meckel syndrome, Meckel-Gruber syndrome.

dysenteric
dysenteric (dis-en-tar′ik)

Relating to or suffering from dysentery.

dysentery
dysentery (dis-en-tar-e)

A disease marked by frequent watery stools, often with blood and mucus, and characterized clinically by pain, tenesmus, fever, and dehydration. [G. dysenteria, fr. dys-, bad, + entera, bowels]
amebic d. diarrhea resulting from ulcerative inflammation of the colon, caused chiefly by infection with Entamoeba histolytica; may be mild or severe and also may be associated with amebic infection of other organs.
bacillary d. infection with Shigella dysenteriae, S. flexneri, or other organisms.
balantidial d. a type of colitis resembling in many respects amebic d.; caused by the parasitic ciliate, Balantidium coli.
bilharzial d. d. due to infection with Schistosoma mansoni, S. haematobium, or S. japonicum.
fulminating d. SYN: malignant d..
helminthic d. d. caused by infection with parasitic worms.
malignant d. d. in which the symptoms are intensely acute, leading to prostration, collapse, and often death. SYN: fulminating d..
viral d. profuse watery diarrhea thought to be caused by infection with a virus.

dyserethism
dyserethism (dis-er′e-thizm)

A condition of slow response to stimuli. [dys- + G. erethismos, irritation]

dysergia
dysergia (dis-er′je-a)

Lack of harmonious action between the muscles concerned in executing any definite voluntary movement. [dys- + G. ergon, work]

dysesthesia
dysesthesia (dis-es-the′ze-a)

1. Impairment of sensation short of anesthesia. 2. A condition in which a disagreeable sensation is produced by ordinary stimuli; caused by lesions of the sensory pathways, peripheral or central. 3. Abnormal sensations experienced in the absence of stimulation. [G. dysaisthesia, fr. dys-, hard, difficult, + aisthesis, sensation]

dysfibrinogenemia
dysfibrinogenemia (dis′fi-brin′o-je-ne′me-a) [MIM*134820]

An autosomal dominant disorder of qualitatively abnormal fibrinogens of various types; each type is named for the city in which the abnormal fibrinogen was discovered. Examples include: 1) Amsterdam, Bethesda II, Cleveland, Los Angeles, Saint Louis, Zurich I and II: major defect, aggregation of fibrin monomers; thrombin time prolonged; inhibitory effect on normal clotting; asymptomatic; 2) Bethesda I and Detroit: major defect, fibrinopeptide release; thrombin time prolonged; inhibitory effect on normal clotting; abnormal bleeding; 3) Baltimore: major defect, fibrinopeptide release; thrombin time prolonged; no inhibitory effect on normal clotting; bleeding and thrombosis; 4) Leuven: major defect, questionable aggregation of fibrin monomers; thrombin time prolonged; slight inhibitory effect on normal clotting; abnormal bleeding; 5) Metz: major defect unreported; thrombin time infinite; effect on normal clotting unreported; abnormal bleeding; 6) Nancy: major defect, aggregation of fibrin monomers; thrombin time prolonged; slight inhibitory effect on normal clotting; asymptomatic; 7) Oklahoma: major defect unreported; thrombin time normal; no effect on normal clotting; abnormal bleeding; 8) Oslo: major defect unreported; thrombin time shortened; effect on normal clotting unreported; abnormal thrombosis; 9) Parma: major defect unreported; thrombin time infinite; no inhibitory effect on normal clotting; abnormal bleeding; 10) Paris I: major defect unreported; thrombin time infinite; inhibitory effect on normal clotting; asymptomatic; 11) Paris II: major defect unreported; thrombin time prolonged; inhibitory effect on normal clotting; asymptomatic; 12) Troyes: major defect unreported; thrombin time prolonged; effect on normal clotting unreported; asymptomatic; 13) Vancouver: major defect unreported; thrombin time prolonged; no effect on normal clotting; abnormal bleeding; 14) Wiesbaden: major defect, aggregation of fibrin monomers; thrombin time prolonged; inhibitory effect on normal clotting; bleeding and thrombosis.

dysfunction
dysfunction (dis-funk′shun)

Abnormal or difficult function.
constitutional hepatic d. SYN: familial nonhemolytic jaundice.
dental d. abnormal functioning of dental structures.
minimal brain d. attention deficit disorder.
papillary muscle d. impaired function of a papillary muscle, usually due to ischemia or infarction, with resulting incompetence of the mitral (rarely tricuspid) valve. SYN: papillary muscle syndrome.
phagocyte d. (fa′go-sit) disorder of phagocytic function.
placental d. SYN: dysmature (3) .
psychosexual d., sexual d. a disturbance of sexual functioning, e.g., impotence, premature ejaculation, anorgasmia, presumed to be of psychological rather than physical etiology.
sphincter of Oddi d. structural or functional abnormality of the sphincter of Oddi that interferes with bile or pancreatic duct drainage. SYN: biliary dyskinesia.
temporomandibular joint d. (TMD, TMJ) chronic or impaired function of the temporomandibular articulation. See temporomandibular arthrosis, myofascial pain-d. syndrome.

dysgammaglobulinemia
dysgammaglobulinemia (dis-gam′a-glob′u-li-ne′me-a)

An immunoglobulin abnormality, a disturbance of the percentage distribution of γ-globulins or selective deficiency of one or more immunoglobulins.

dysgenesis
dysgenesis (dis-jen′e-sis)

Defective development. [dys- + G. genesis, generation]
cortical d. SYN: cortical dysplasia.
gonadal d. defective gonadal development, varying types and degrees of which have been identified, including gonadal aplasia or agenesis, rudimentary gonads, congenitally defective gonads, and true hermaphroditism; the character of the external genitalia, genital ducts, and secondary sexual development are only sometimes uniquely related to a given type of gonadal d. XO gonadal d. consists of monosomy X with a gonadal streak rather than a true ovary, notably seen in Turner syndrome; XX gonadal d. is an autosomal recessive disorder with a female karyotype, streaked gonads, and primary amenorrhea, but with no body features of Turner syndrome; XY gonadal d. is an X-linked disorder associated with a male karyotype and a female habitus, streaked gonads, and absence of secondary sexual characteristics.
iridocorneal mesenchymal d. d. of cornea and iris, producing pupillary anomalies, posterior embryotoxon, and secondary glaucoma, resulting in part from anomalous development of the ocular mesenchyme.
seminiferous tubule d. rarely used term for a disorder in which the seminiferous tubules exhibit an abnormal cytoarchitecture and extensive hyalinization; the testes are small, and few spermatozoa are formed; the body habitus may be eunuchoid, and gynecomastia may be present; urinary gonadotropin output is usually high, and the incidence of mental deficiency and illness increased; sex chromatin may be male or female, and androgen secretion ranges from subnormal to normal. It is a constant feature of (and the term may be used synonymously with) Klinefelter syndrome. SYN: germinal aplasia.
testicular d. [MIM*305700] a congenital derangement of seminiferous tubular structure and function, resulting in male infertility; the defect in spermatogenesis may be incomplete, as in maturational arrest or premature sloughing, or spermatogenesis may be completely absent, as in the Sertoli-cell-only syndrome.

dysgenic
dysgenic (dis-jen′ik)

Applying to factors that have a detrimental effect upon hereditary qualities, physical or mental.

dysgerminoma
dysgerminoma (dis-jer-mi-no′ma)

A malignant neoplasm of the ovary (counterpart of seminoma of the testis), composed of undifferentiated gonadal germinal cells and occurring more frequently in patients less than 20 years of age. The neoplasms are gray-yellow and firm, contain foci of necrosis and hemorrhage, and tend to be encapsulated; characteristically, they spread by way of lymphatic vessels, but widespread metastases also occur. SYN: disgerminoma. [dys- + L. germen, a bud or sprout, + G. -oma, tumor]

dysgeusia
dysgeusia (dis-goo′se-a)

Distortion or perversion in the perception of a tastant. An unpleasant perception may occur when a normally pleasant taste is present, or the perception may occur when no tastant is present (gustatory hallucination). SYN: parageusia. [dys- + G. geusis, taste]

dysgnathia
dysgnathia (dis-nath′e-a)

Any abnormality that extends beyond the teeth and includes the maxilla or mandible, or both. [dys- + G. gnathos, jaw]

dysgnathic
dysgnathic (dis-nath′ik)

Pertaining to or characterized by abnormality of the maxilla and mandible.

dysgnosia
dysgnosia (dis-no′se-a)

Any cognitive disorder, i.e., any mental illness. [G. d., difficulty of knowing]

dysgonic
dysgonic (dis-gon′ik)

A term used to indicate that the growth of a bacterial culture is slow and relatively poor; used especially in reference to the growth of cultures of the bovine tubercle bacillus (Mycobacterium bovis) SEE ALSO: eugonic. [dys- + G. gonikos, relating to the seed or offspring]

dysgraphia
dysgraphia (dis-graf′e-a)

1. Difficulty in writing. 2. SYN: writer's cramp. [dys- + G. graphe, writing]

dyshematopoiesis
dyshematopoiesis (dis-he′ma-to-poy-e′sis)

Defective formation of the blood. SYN: dyshemopoiesis. [dys- + G. haima (haimat-), blood, + poiesis, making]

dyshematopoietic
dyshematopoietic (dis-he′ma-to-poy-et′ik)

Pertaining to or characterized by dyshematopoiesis. SYN: dyshemopoietic.

dyshemopoiesis
dyshemopoiesis (dis-he′mo-poy-e′sis)

SYN: dyshematopoiesis.

dyshemopoietic
dyshemopoietic (dis-he′mo-poy-et′ik)

SYN: dyshematopoietic.

dyshidria
dyshidria (dis-hid′re-a)

SYN: dyshidrosis.

dyshidrosis
dyshidrosis (dis-i-dro′sis)

A vesicular or vesicopustular eruption of multiple causes that occurs primarily on the volar surfaces of the hands and feet; the lesions spread peripherally but have a tendency to central clearing. SYN: cheiropompholyx, chiropompholyx, dyshidria, dyshidrotic eczema, pompholyx. [dys- + G. hidros, sweat]

dysjunction dysjunction

A separation of parts or structures normally joined; cleavage.
Le Fort III craniofacial d. SYN: craniofacial d. fracture.

dyskaryosis
dyskaryosis (dis-kar-e-o′sis)

Abnormal maturation seen in exfoliated cells that have normal cytoplasm but hyperchromatic nuclei, or irregular chromatin distribution; may be followed by the development of a malignant neoplasm. [dys- + G. karyon, nucleus, + -osis, condition]

dyskaryotic
dyskaryotic (dis-kar-e-ot′ik)

Pertaining to or characterized by dyskaryosis.

dyskeratoma
dyskeratoma (dis-ker-a-to′ma)

A skin tumor exhibiting dyskeratosis. [dys- + G. keras, horn, + -oma, tumor]
warty d. a benign solitary tumor of the skin, usually of the scalp, face, or neck, with a central keratotic plug; it appears to arise from a hair follicle, and microscopically resembles a lesion of keratosis follicularis but is larger, with more extensive epithelial downgrowth. SYN: isolated dyskeratosis follicularis.

dyskeratosis
dyskeratosis (dis′ker-a-to′sis)

1. Premature keratinization in individual epithelial cells that have not reached the keratinizing surface layer; dyskeratotic cells generally become rounded and they may break away from adjacent cells and fall off. 2. Epidermalization of the conjunctival and corneal epithelium. 3. A disorder of keratinization. [dys- + G. keras, horn, + -osis, condition]
benign d. d. that may occur in congenital and bullous diseases of the skin.
d. congenita [MIM*305000] nail dystrophy, oral leukoplakia, and reticular pigmentation of the skin, testicular atrophy with anemia progressing most commonly to pancytopenia; X-linked recessive inheritance, caused by mutation in the DKC1 gene encoding dyskenin on Xq.
intraepithelial d. [MIM*127600] an autosomal dominant condition consisting of white spongy lesions of the buccal mucosa, floor of the mouth, ventral lateral tongue, gingiva and palate. Transient gelatinous plaques form over the cornea, which may produce temporary blindness;
isolated d. follicularis SYN: warty dyskeratoma.

dyskeratotic
dyskeratotic (dis′ker-a-tot′ik)

Relating to or characterized by dyskeratosis.

dyskinesia
dyskinesia (dis-ki-ne′ze-a) [MIM*242650]

Difficulty in performing voluntary movements. Term usually used in relation to various extrapyramidal disorders. SYN: dyscinesia. [dys- + G. kinesis, movement]
biliary d. SYN: sphincter of Oddi dysfunction.
extrapyramidal dyskinesias abnormal involuntary movements attributed to pathologic states of one or more parts of the striate body and characterized by insuppressible, stereotyped, automatic movements that cease only during sleep; e.g., Parkinson disease; chorea; athetosis; hemiballism.
lingual-facial-buccal d. SYN: tardive d..
tardive d. involuntary movements of the facial muscles and tongue, often persistent, that develop as a late complication of some neuroleptic therapy, more likely with typical antipsychotics. SYN: lingual-facial-buccal d..
tracheobronchial d. degeneration of elastic and connective tissue of bronchi and trachea.

dyskinesis dyskinesis

SYN: dyskinesia.
ciliary d. 1. absent or impaired motion of the cilia, occurring as a primary or secondary disorder; SEE ALSO: Kartagener syndrome. 2. associated with recurrent infections in the respiratory tract.

dyskinetic
dyskinetic (dis-ki-net′ik)

Denoting or characteristic of dyskinesia.

dyslexia
dyslexia (dis-lek′se-a)

Impaired reading ability with a competence level below that expected on the basis of the individual's level of intelligence, and in the presence of normal vision and letter recognition and normal recognition of the meaning of pictures and objects. SYN: incomplete alexia. [dys- + G. lexis, word, phrase]

dyslexic
dyslexic (dis-lek′sik)

Relating to, or characterized by, dyslexia.

dyslogia
dyslogia (dis-lo′je-a)

Impairment of speech and reasoning as the result of a mental disorder. [dys- + G. logos, speaking, reason]

dysmasesis
dysmasesis (dis-ma-se′sis)

Difficulty in mastication. [dys- + G. masesis, chewing]

dysmature
dysmature (dis′ma-tur)

1. Denoting faulty development or ripening; often connoting structural and/or functional abnormalities. 2. In obstetrics, denoting an infant whose birth weight is inappropriately low for its gestational age. 3. Immature development of the placenta so that normal function does not occur. SYN: placental dysfunction.

dysmaturity
dysmaturity (dis′ma-choor-i-te)

Syndrome of an infant born with relative absence of subcutaneous fat, wrinkling of the skin, prominent finger and toe nails, and meconium staining of the infant's skin and of the placental membranes; often associated with postmaturity or placental insufficiency.

dysmelia
dysmelia (dis-me′le-a)

Congenital abnormality characterized by missing or foreshortened limbs. See amelia, phocomelia. [dys- + G. melos, limb]

dysmenorrhea
dysmenorrhea (dis-men-or-e′a)

Difficult and painful menstruation. SYN: menorrhalgia. [dys- + G. men, month, + rhoia, a flow]
functional d. SYN: primary d..
mechanical d. d. due to obstruction of discharge of menstrual blood, as in cervical stenosis. SYN: obstructive d..
membranous d. d. accompanied by an exfoliation of the menstrual decidua.
obstructive d. SYN: mechanical d..
ovarian d. a form of secondary d. due to disease of an ovary.
primary d. d. due to a functional disturbance and not due to inflammation, new growths, or anatomic factors. SYN: functional d..
secondary d. d. due to inflammation, infection, tumor, or anatomical factors.
spasmodic d. d. accompanied by painful contractions of the uterus.
tubal d. a form of secondary d. due to stenosis or other abnormal condition of the fallopian tubes.
ureteric d. a form of secondary d. characterized by pain due to spasm of the ureter occurring at the time of the menses.
uterine d. a form of secondary d. resulting from disease of the uterus.
vaginal d. a form of secondary d. due to obstruction or other abnormal condition in the vagina.

dysmetria
dysmetria (dis-me′tre-a, -met′re-a)

An aspect of ataxia, in which the ability to control the distance, power, and speed of an act is impaired. Usually used to describe abnormalities of movement caused by cerebellar disorders. SEE ALSO: hypermetria, hypometria. [dys- + G. metron, measure]
ocular d. abnormality of ocular movements in which the eyes overshoot on attempting to fixate an object.

dysmorphia
dysmorphia (dis-mor′fe-a)

SYN: dysmorphism.

dysmorphism
dysmorphism (dis-mor′fizm)

Abnormality of shape. SYN: dysmorphia. [G. dysmorphia, badness of form]

dysmorphogenesis
dysmorphogenesis (dis′mor-fo-jen′e-sis)

The process of abnormal tissue formation. [dys- + G. morphe, form, + genesis, production]

dysmorphology
dysmorphology (dis-mor-fol′o-je)

General term for the study of, or the subject of, abnormal development of tissue form. A branch of clinical genetics. [dys- + G. morphe, form, + logos, study]

dysmorphophobia
dysmorphophobia (dis′mor-fo-fo′be-a)

SYN: body dysmorphic disorder. [dys- + G. morphe, form, + phobos, fear]

dysmyelination
dysmyelination (dis-mi-e-li-na′shun)

Improper laying down or breakdown of a myelin sheath of a nerve fiber, caused by abnormal myelin metabolism.

dysmyotonia
dysmyotonia (dis-mi-o-to′ne-a)

Abnormal muscular tonicity (either hyper- or hypo-). See dystonia. [dys- + G. mys, muscle, + tonos, tension, tone]

dysnystaxis
dysnystaxis (dis-nis-tak′sis)

A condition of half sleep. SYN: light sleep. [dys- + G. nystaxis, drowsiness]

dysodontiasis
dysodontiasis (dis′o-don-ti′a-sis)

Difficulty or irregularity in the eruption of the teeth. [dys- + G. odous, tooth, + -iasis, condition]

dysontogenesis
dysontogenesis (dis′on-to-jen′e-sis)

Defective embryonic development. [dys- + G. on, being, + genesis, origin]

dysontogenetic
dysontogenetic (dis′on-to-je-net′ik)

Characterized by dysontogenesis.

dysorexia
dysorexia (dis-o-rek′se-a)

Diminished or perverted appetite. [dys- + G. orexis, appetite]

dysosmia
dysosmia (dis-oz′me-a)

Distortion or perversion in the perception of an odorant; an unpleasant perception may occur when a normally pleasant odor is present, or the perception may occur when no odorant is present (olfactory hallucination). SYN: parosmia, parosphresia. [dys- + G. osme, smell]

dysosteogenesis
dysosteogenesis (dis′os-te-o-jen′e-sis)

Defective bone formation. SYN: dysostosis. [dys- + G. osteon, bone, + genesis, production]

dysostosis
dysostosis (dis-os-to′sis)

SYN: dysosteogenesis. [dys- + G. osteon, bone, + -osis, condition]
acrofacial d. mandibulofacial d. associated with malformations of the extremities such as defective radius and thumbs, and radioulnar synostosis. SEE ALSO: Treacher Collins syndrome. SYN: acrofacial syndrome.
cleidocranial d., clidocranial d. [MIM*119600] a developmental disorder characterized by absence or hypoplasia of clavicles, box-shaped skull with open sutures, frontal bossing, womian bones, ability to oppose shoulders, and missing teeth; autosomal dominant inheritance, caused by mutation in the transcription factor gene (CBFA1) encoding core-binding factor, runt domain, alpha-subunit 1 on 6p. There is an autosomal recessive form [MIM*216330]. SYN: cleidocranial dysplasia, clidocranial dysplasia, craniocleidodysostosis.
craniofacial d. [MIM*123500] SYN: Crouzon syndrome.
mandibuloacral d. [MIM*248370] an autosomal recessive disorder characterized by hypoplastic mandible, dental crowding, acro-osteolysis, stiff joints, and atrophy of the skin of the hands and feet; clavicles are hypoplastic, cranial sutures are wide, and multiple wormian bones are present.
mandibulofacial d. a variable syndrome of malformations primarily of derivatives of the first branchial arch; characterized by palpebral fissures sloping outward and downward with notches or colobomas in the outer third of the lower lids, bony defects or hypoplasia of malar bones and zygoma, hypoplasia of the mandible, macrostomia with high or cleft palate and malposition and malocclusion of teeth, low-set malformed external ears, atypical hair growth, and occasional pits or clefts between mouth and ear. SEE ALSO: Treacher Collins syndrome. SYN: mandibulofacial dysotosis syndrome, mandibulofacial dysplasia.
metaphysial d. a rare developmental abnormality of the skeleton in which metaphyses of tubular bones are expanded by deposits of cartilage.
d. multiplex specific pattern of radiographic changes observed in many lysosomal storage disorders.
orodigitofacial d. SYN: orofaciodigital syndrome.
otomandibular d. hypoplasia of the mandible, often with malformation of the temporomandibular joint, associated with malformations of the ear but not eye malformations or malar defects. SYN: otomandibular syndrome.
peripheral d. [MIM*170700] d. of the metacarpals and metatarsals, accompanied by variable facial features; possibly autosomal dominant inheritance.

dyspallia
dyspallia (dis-pal′e-a)

Developmental distortion of the brain mantle. [dys- + L. pallium, cloak]

dyspareunia
dyspareunia (dis-pa-roo′ne-a)

Occurrence of pain during sexual intercourse. [dys- + G. pareunos, lying beside, fr. para, beside, + eune, a bed]

dyspepsia
dyspepsia (dis-pep′se-a)

Impaired gastric function or “upset stomach” due to some disorder of the stomach; characterized by epigastric pain, sometimes burning, nausea, and gaseous eructation. SYN: gastric indigestion. [dys- + G. pepsis, digestion]
acid d. d. associated with excess gastric acidity.
adhesion d. pain, d., and other symptoms alleged to result from perigastric adhesions.
atonic d. d. with impaired tone in the muscular walls of the stomach. SYN: functional d. (1) .
fermentative d. d. accompanied by fermentation of the contents of the stomach, usually occurring in gastric dilation.
flatulent d. d. with frequent eructations of swallowed air, sometimes without underlying organic disease.
functional d. 1. SYN: atonic d.. 2. SYN: nervous d..
nervous d. d. associated with nervousness, tension, or anxiety. SYN: functional d. (2) .
reflex d. functional d. excited by reflex irritation from disease elsewhere than in the stomach or intestines.

dyspeptic
dyspeptic (dis-pep′tik)

Relating to or suffering from dyspepsia.

dysphagia
dysphagia, dysphagy (dis-fa′je-a, dis′fa-je)

Difficulty in swallowing. SEE ALSO: aglutition. [dys- + G. phago, to eat]
d. lusoria d. said to be due to compression by the right subclavian artery arising abnormally from the descending aorta and passing behind the esophagus. [coinage from L. lusus naturae, a sport of nature]
d. nervosa, nervous d. SYN: esophagism.
sideropenic d. SYN: Plummer-Vinson syndrome.
vallecular d. d. caused by food becoming lodged in a vallecula above the epiglottis. SYN: Barclay-Baron disease.

dysphagocytosis
dysphagocytosis (dis-fag′o-si-to′sis)

Disordered phagocytosis, especially failure of cells to ingest and digest bacteria.
congenital d. SYN: chronic granulomatous disease.

dysphasia
dysphasia (dis-fa′ze-a)

Impairment in the production of speech and failure to arrange words in an understandable way; caused by an acquired lesion of the brain. SYN: dysphrasia. [dys- + G. phasis, speaking]

dysphemia
dysphemia (dis-fe′me-a)

Disordered phonation, articulation, or hearing due to emotional or mental deficits. [dys- + G. pheme, speech]

dysphonia
dysphonia (dis-fo′ne-a)

Altered voice production. [dys- + G. phone, voice]
abductor spasmodic d. a breathy form of spasmodic d. caused by excessive and long vocal cord opening for voiceless phonemes extending into vowels.
adductor spasmodic d. a form of spasmodic d. in which excessive closure of the vocal cords affects the initiation and maintenance of phonation.
d. plicae ventricularis phonation with the ventricular bands rather than with the vocal cords.
spasmodic d. a spasmodic contradiction of the intrinsic muscles of the larynx excited bt attempted phonation, producing either adductor or abductor subtypes caused by a central nervous system disorder. A localized form of movement disorder. SYN: d. spastica, spastic d..
spastic d. SYN: spasmodic d..
d. spastica SYN: spasmodic d..

dysphoria
dysphoria (dis-for′e-a)

A mood of general dissatisfaction, restlessness, depression, and anxiety; a feeling of unpleasantness or discomfort. [dys- + G. phora, a bearing]
late luteal phase d. SYN: premenstrual syndrome.

dysphrasia
dysphrasia (dis-fra′ze-a)

SYN: dysphasia. [dys- + G. phrasis, speaking]

dyspigmentation
dyspigmentation (dis′pig-men-ta′shun)

Any abnormality in the formation or distribution of pigment, especially in the skin; usually applied to an abnormal reduction in pigmentation (depigmentation). SEE ALSO: albinism.

dyspinealism
dyspinealism (dis-pin′e-al-izm)

Obsolete term for the syndrome supposed to result from the deficiency of pineal gland secretion.

dyspituitarism
dyspituitarism (dis-pi-too′i-ter-izm)

The complex of phenomena due to excessive or deficient secretion by the pituitary gland.

dysplasia
dysplasia (dis-pla′ze-a)

Abnormal tissue development. SEE ALSO: heteroplasia. [dys- + G. plasis, a molding]
anhidrotic ectodermal d. [MIM*305100] a disorder characterized by absent or defective sweat glands, saddle-shaped nose, hyperpigmentation around the eyes, malformed or missing teeth, sparse hair, dysplastic nails, smooth, finely wrinkled skin, syndactyly, absent breast tissue, and occasionally mental retardation; X-linked recessive inheritance, caused by mutation in the ED1 gene on chromosome Xq. There is also an autosomal recessive form [MIM*224900]. SYN: hypohidrotic ectodermal d..
anterofacial d., anteroposterior facial d., anteroposterior d. abnormal growth of the face or cranium in an anteroposterior direction as seen and measured with a cephalogram.
asphyxiating thoracic d. [MIM*208500] SYN: asphyxiating thoracic dystrophy.
branchiootorenal d. an autosomal dominant disorder manifested by branchial cysts, preauricular skin tags or sinuses, ear anomalies, and kidney malformations. SYN: BOR syndrome.
bronchopulmonary d. chronic pulmonary insufficiency seen primarily in infants born prematurely; defined clinically as a persistent supplemental oxygen requirement at 1 month of age and typically seen in infants who required positive pressure ventilation.
cerebral d. abnormal development of the telencephalon.
cervical d. d. of the uterine cervix, epithelial atypia involving part or all of the thickness of cervical squamous epithelium, occurring most often in young women; appears to regress frequently, but may progress over a long period to carcinoma; severe d. may be microscopically indistinguishable from carcinoma in situ.
chondroectodermal d. [MIM*225500] triad of chondrodysplasia, ectodermal d., and polydactyly, with congenital heart defects in over half of patients; autosomal recessive inheritance. Maps to human chromosome 4p16. SYN: Ellis-van Creveld syndrome.
cleidocranial d., clidocranial d. SYN: cleidocranial dysostosis.
cochlear d. failure of the bony cochlea to develop completely.
congenital ectodermal d. incomplete development of the epidermis and skin appendages; the skin is smooth and hairless, the facies abnormal, and the teeth and nails may be affected; sweating may be deficient. SYN: congenital ectodermal defect.
congenital hip d. SYN: developmental hip d..
cortical d. a malformative disorganization of the cytoarchitecture of the cortex relative to neurons. SYN: cortical dysgenesis, neuronal migration abnormality.
craniocarpotarsal d. SYN: craniocarpotarsal dystrophy.
craniodiaphysial d. [MIM*218300] small stature, thickening of the cranial bones with sclerosis and diaphysial widening of tubular bones; autosomal recessive inheritance. There may also be an autosomal dominant form [MIM 122860].
craniometaphysial d. syndrome of metaphysial d. associated with severe sclerosis and overgrowth of bones of the skull (leontiasis ossea) and with hypertelorism.
dentin d. a hereditary disorder of the teeth, involving both primary and permanent dentition, in which the clinical morphology and color of the teeth are normal, but the teeth radiographically exhibit short roots [MIM125400], obliteration of the pulp chambers and canals, and mobility and premature exfoliation; autosomal dominant inheritance. In another type of dentin disease the teeth are opalescent [MIM 125420].
developmental hip d. a developmental abnormality in which a neonate's hips easily become dislocated; etiology is complex, with mechanical, familial, hormonal, and birthing presentation all contributing; female predominance is 9:1. SYN: congenital hip d..
diaphysial d. progressive, symmetrical fusiform enlargement of the shafts of long bones characterized by the formation of excessive new periosteal and endosteal bone and irregular conversion of this cortical bone into cancellous bone; anemia does not occur as a rule, as in osteopetrosis. SYN: Engelmann disease.
diastrophic d. [MIM*222600] a skeletal d. characterized by scoliosis, hitchhiker thumb due to shortening of the first metacarpal bone, cleft palate, malformed ear with calcification, chondritis, shortening of the Achilles tendon, clubbed foot, and characteristic radiologic findings; autosomal recessive inheritance, caused by mutation in the diastrophic d. sulfate transporter gene (DTDST) on chromosome 5q. SYN: diastrophic dwarfism.
ectodermal d. a congenital defect of the ectodermal tissues, including the skin and its appendages; associated with d. of the teeth and hyperthermia. See anhidrotic ectodermal d., hidrotic ectodermal d..
enamel d. SYN: amelogenesis imperfecta.
d. epiphysealis multiplex SYN: multiple epiphyseal d..
d. epiphysialis hemimelia SYN: tarsomegaly.
d. epiphysialis punctata SYN: chondrodysplasia punctata.
epithelial d. a disorder of differentiation of epithelial cells which may regress, remain stable, or progress to invasive carcinoma.
faciodigitogenital d. a syndrome of ocular hypertelorism, anteverted nostrils, broad upper lip, saddle-bag or shawl scrotum, protruding umbilicus, and laxity of ligaments resulting in genu recurvatum, flat feet, and hyperextensible fingers; the X-linked form [MIM*305400] is caused by mutation in the FGD1 gene on Xp; autosomal dominant [MIM*100050] and recessive [MIM*227300] forms also exist. SYN: Aarskog-Scott syndrome.
familial white folded d. SYN: white sponge nevus.
fibromuscular d. idiopathic nonatherosclerotic disease leading to stenosis of arteries, usually the renal arteries, and hypertension; two varieties are fibromuscular hyperplasia and perimuscular fibrosis.
fibrous d. of bone a disturbance of medullary bone maintenance in which bone undergoing physiologic lysis is replaced by abnormal proliferation of fibrous tissue, resulting in asymmetric distortion and expansion of bone; may be confined to a single bone (monostotic fibrous d.) or involve multiple bones (polyostotic fibrous d.).
fibrous d. of jaws SYN: cherubism.
florid osseous d., cemental d. SYN: sclerotic cemental mass.
hidrotic ectodermal d. [MIM*129500] congenital dystrophy of the nails and hair with thickened nails and sparse or absent scalp hair; often associated with keratoderma of the palms and soles; teeth and sweat gland function are normal; autosomal dominant inheritance.
hypohidrotic ectodermal d. SYN: anhidrotic ectodermal d..
mandibulofacial d. SYN: mandibulofacial dysostosis.
McKusick metaphyseal d. SYN: cartilage-hair hypoplasia.
metaphysial d. an abnormality that occurs when new bone at the metaphyses of long bones fails to undergo remodeling to the normal tubular structure; the ends of long bones appear to be expanded and porotic, with thin cortex; there may be an associated overgrowth of cranial bones (craniometaphysial d.).
Mondini d. congenital anomaly of osseus and membranous otic labyrinth characterized by aplastic cochlea, and deformity of the vestibule and semicircular canals with partial or complete loss of auditory and vestibular function; may be associated with spontaneous cerebrospinal fluid otorrhoea resulting in meningitis. SEE ALSO: Mondini hearing impairment.
monostotic fibrous d. fibrous d. of a single bone. SYN: localized osteitis fibrosa, osteitis fibrosa circumscripta.
mucoepithelial d. [MIM*158310] an epithelial cell dishesive disease characterized by red, periorificial mucosal lesions of oral, nasal, vaginal, urethral, anal, bladder, and conjunctival mucosa, with cataracts, follicular keratosis, nonscarring alopecia, frequent pulmonary infections, pneumothorax, and sometimes cor pulmonale; autosomal dominant inheritance.
multiple epiphyseal d. (EDM) a disorder of epiphyses characterized by difficulty in walking, pain and stiffness of joints, stubby fingers, and often short stature; on X-ray examination, the epiphyses are irregular and mottled, the ossification centers are late in appearance and may be multiple, but the vertebrae are normal. There are at least 3 forms of autosomal dominant inheritance: EDM1 [MIM*132400] due to mutation in the cartilage oligomeric matrix protein gene (COMP) on chromosome 19p; EDM2 [MIM*600304], due to mutation in the type IX collagen gene (COL9A2) on 1p; and EDM3 [MIM*600969], which is linked to an unknown locus. There is also an autosomal recessive form [MIM*226900]. SYN: d. epiphysealis multiplex.
neuronal intestinal d. SYN: neuronal hyperplasia.
oculoauriculovertebral d., OAV d. [MIM*257700] a syndrome characterized by epibulbar dermoids, preauricular appendages, micrognathia, and vertebral and other anomalies. SYN: Goldenhar syndrome, OAV syndrome.
oculodentodigital d. [MIM*164200] microphthalmia, coloboma, or anomalies of the iris associated with malformed and malpositioned teeth and with anomalies of the fingers including syndactyly, campylodactyly, or absent phalanges; autosomal dominant inheritance. There is also a recessive form in which the ocular manifestation is more severe [MIM*257850].
oculovertebral d. microphthalmia, colobomas, or anophthalmia with small orbit, twisted face due to unilateral d. of maxilla, macrostomia with malformed teeth and malocclusion, vertebral malformations, and branched and hypoplastic ribs. SYN: oculovertebral syndrome, Weyers-Thier syndrome.
odontogenic d. SYN: odontodysplasia.
ophthalmomandibulomelic d. [MIM*164900] an autosomal dominant disorder with corneal clouding and multiple abnormalities of the mandible and limbs.
otospondylomegaepiphyseal d. SYN: chondrodystrophy with sensorineural deafness.
periapical cemental d. a benign, painless, non-neoplastic condition of the jaws which occurs almost exclusively in middle-aged black females; lesions are usually multiple, most frequently involve vital mandibular anterior teeth, surround the root apices, and are initially radiolucent (becoming more opaque as they mature). SYN: periapical osteofibrosis.
polyostotic fibrous d. the occurrence of lesions of fibrous d. in multiple bones, commonly on one side of the body; may occur with areas of pigmentation and endocrine dysfunction (McCune-Albright syndrome). SYN: multifocal osteitis fibrosa, osteitis fibrosa disseminata.
pseudoachondroplastic spondyloepiphysial d. SYN: pseudoachondroplasia.
retinal d. an overgrowth of glial tissue compensating for aplasia of sensory elements.
septooptic d. congenital optic nerve hypoplasia associated with midline cerebral anomalies. SYN: de Morsier syndrome.
skeletal dysplasias a heterogeneous group of disorders (over 120 types), each of which results in numerous disturbances of the skeletal system and most of which include dwarfism. SEE ALSO: chondrodystrophy.
spondyloepiphyseal d. a group of conditions characterized by growth deficiency of the vertebral column with flattening of the vertebrae or platyspondyly, lack of ossification of the epiphyses, short-trunk dwarfism with limb shortening, and sometimes with other malformations; autosomal dominant [MIM*183900 and MIM*184100], autosomal recessive [MIM*208230 and MIM*271600], and X-linked recessive [MIM*313400] inheritance have been described.
spondyloepiphyseal d. congenita (SEDC) [MIM*183900] a skeletal d. characterized by short-trunk dwarfism with short limbs, delayed ossification of the pubic rami and femoral and tibial epiphyses, flattening of the vertebral bodies, myopia, retinal detachment, and cleft palate; autosomal dominant inheritance caused by mutation in the type II collagen gene (COL2A1) on 12q.
spondyloepiphyseal d. tarda a skeletal d. of later onset, usually in the second decade, characterized by short stature, flattening of the vertebrae, epiphyseal involvement with bony fusion of the hip joint, premature osteoarthritis, and distinctive radiographic findings. Autosomal dominant [MIM*184100] and X-linked recessive [MIM*313400] forms exist.
ventriculoradial d. a congenital syndrome consisting of a ventricular septal defect with associated absence of thumb or radius.

dysplastic
dysplastic (dis-plas′tik)

Pertaining to or marked by dysplasia.

dyspnea
dyspnea (disp-ne′a)

Shortness of breath, a subjective difficulty or distress in breathing, usually associated with disease of the heart or lungs; occurs normally during intense physical exertion or at high altitude. [G. dyspnoia, fr. dys-, bad, + pnoe, breathing]
cardiac d. shortness of breath of cardiac origin.
exertional d. excessive shortness of breath after exercise.
expiratory d. difficulty with the expiratory phase of breathing, often due to obstruction in the larynx or large bronchi, such as by a foreign body.
functional d. shortness of breath without apparent underlying disease.
nocturnal d. d. occurring at night, several hours after assuming recumbent position. Occurs in heart failure and results from reabsorption of water from dependent areas after removal of effect of gravity, causing hypervolemia, aggravating left-ventricular failure.
paroxysmal nocturnal d. acute d. appearing suddenly at night, usually waking the patient from sleep; caused by pulmonary congestion with or without pulmonary edema that results from left-sided heart failure following mobilization of fluid from dependent areas after lying down.
Traube d. obsolete eponym for inspiratory d. with maximal expansion of the chest and a slow respiratory rhythm.

dyspneic
dyspneic (disp-ne′ik)

Out of breath; relating to or suffering from dyspnea.

dyspraxia
dyspraxia (dis-prak′se-a)

Impaired or painful functioning in any organ. [dys- + G. praxis, a doing]

dysprosium
dysprosium (Dy) (dis-pro′se-um)

A metallic element of the lanthanide (rare earth) series, atomic no. 66, atomic wt. 162.50. [G. dysprositos, hard to get at]

dysproteinemia
dysproteinemia (dis-pro′ten-e′me-a)

An abnormality in plasma proteins, usually in immunoglobulins.

dysproteinemic
dysproteinemic (dis-pro-ten-e′mik)

Relating to dysproteinemia.

dysraphism
dysraphism, dysraphia (dis′ra-fizm, dis-raf′e-a)

Defective fusion, especially of the neural folds, resulting in status dysraphicus or neural tube defect. [dys- + G. rhaphe, suture]
spinal d. a general term used to describe a collection of congenital abnormalities that include defects in the vertebrae and underlying spine or nerve roots.

dysrhythmia
dysrhythmia (dis-rith′me-a)

Defective rhythm.rhythm. Cf.:arrhythmia. [dys- + G. rhythmos, rhythm]
cardiac d. any abnormality in the rate, regularity, or sequence of cardiac activation.
electroencephalographic d. a diffusely irregular brain wave tracing.
esophageal d. abnormal motility of the muscular layers of the esophageal wall, such as occurs in esophageal spasm.
paroxysmal cerebral d. a diffusely abnormal electroencephalogram often seen with epilepsy.

dyssomnia
dyssomnia (dis-som′ne-a)

Disturbance of normal sleep or rhythm pattern.

dysspondylism
dysspondylism (dis-spon′di-lizm)

An abnormality of development of the spine or vertebral column. [dys- + G. spondylos, vertebra]

dysstasia
dysstasia (dis-sta′se-a)

Difficulty in standing. SYN: dystasia. [dys- + G. stasis, standing]

dysstatic
dysstatic (dis-tat′ik)

Marked by difficulty in standing.

dyssyllabia
dyssyllabia (dis-il-la′be-a)

SYN: syllable-stumbling. [dys- + G. syllabe, syllable]

dyssynergia
dyssynergia (dis-in-er′je-a)

An aspect of ataxia, in which an act is not performed smoothly or accurately because of lack of harmonious association of its various components; usually used to describe abnormalities of movement caused by cerebellar disorders. [dys- + G. syn, with, + ergon, work]
d. cerebellaris myoclonica a familial disorder beginning in late childhood, characterized by progressive cerebellar ataxia, action myoclonus and preserved intellect. Probably due to multiple causes, mitochondrial abnormalities being one. SYN: dentatorubral cerebellar atrophy with polymyoclonus.
detrusor sphincter d. a disturbance of the normal relationship between bladder (detrusor) contraction and sphincter relaxation during voluntary or involuntary voiding efforts.

dystasia
dystasia

SYN: dysstasia.

dystelephalangy
dystelephalangy (dis-tel′e-fa-lan′je)

Bowing of the distal phalanx of the little finger. [dys- + G. telos, end, + phalanx]

dysthymia
dysthymia (dis-thi′me-a)

A chronic mood disorder manifested as depression for most of the day, more days than not, accompanied by some of the following symptoms: poor appetite or overeating, insomnia or hypersomnia, low energy or fatigue, low self-esteem, poor concentration, difficulty making decisions, and feelings of hopelessness. See mood disorders, under disorder, endogenous depression, exogenous depression. [dys- + G. thymos, mind, emotion]

dysthymic
dysthymic (dis-thi′mik)

Relating to dysthymia.

dystocia
dystocia (dis-to′se-a)

Difficult childbirth. [G. dystokia, fr. dys-, difficult, + tokos, childbirth]
arrest of active phase d. stoppage of further cervical dilation for longer than 2 hours after labor has entered active phase (generally defined as active contraction with at least 4 cm of cervical dilatation); causes include inadequate uterine contractions and cephalopelvic disproportion.
arrest of descent d. failure of fetus to descend after an hour in second stage despite maternal effort; typically due to inadequate maternal effort, fetal malposition, or fetal size.
fetal d. d. due to an abnormality of the fetus.
maternal d. d. caused by an abnormality or physical problem in the mother.
placental d. retention or difficult delivery of the placenta.
shoulder d. arrest of normal labor after delivery of the head by impaction of the anterior shoulder against the symphysis pubis.

dystonia
dystonia (dis-to′ne-a)

A state of abnormal (either hypo- or hyper-) tonicity in any of the tissues resulting in impairment of voluntary movement. [dys- + G. tonos, tension]
d. lenticularis d. resulting from a lesion of the lenticulate nucleus.
d. musculorum deformans a genetic, environmental, or idiopathic disorder, usually beginning in childhood or adolescence, marked by muscular contractions that distort the spine, limbs, hips, and sometimes the cranial-innervated muscles. The abnormal movements are increased by excitement and, at least initially, abolished by sleep. The musculature is hypertonic when in action, hypotonic when at rest. Hereditary forms usually begin with involuntary posturing of the foot or hand (autosomal recessive form [MIM*224500]) or of the neck or trunk (autosomal dominant form [MIM*128100]); both forms may progress to produce contortions of the entire body. SYN: torsion disease of childhood, torsion d., Ziehen-Oppenheim disease.
torsion d. SYN: d. musculorum deformans.

dystonic
dystonic (dis-ton′ik)

Pertaining to dystonia.

dystopia
dystopia (dis-to′pe-a)

Faulty or abnormal position of a part or organ. SYN: allotopia, malposition. [dys- + G. topos, place]
pituitary d. failure of union of neurohypophysis and adenohypophysis.

dystopic
dystopic (dis-top′ik)

Pertaining to, or characterized by, dystopia. SEE ALSO: ectopic.

dystrophia
dystrophia (dis-tro′fe-a)

SYN: dystrophy. [L. fr. G. dys-, bad, + trophe, nourishment]
d. adiposogenitalis SYN: adiposogenital dystrophy.
d. brevicollis a condition marked by symptoms of d. adiposogenitalis together with a deforming shortness of the neck, but without synostosis of the cervical vertebrae seen in Klippel-Feil syndrome.
d. myotonica SYN: myotonic dystrophy.
d. unguium dystrophy of the nails.

dystrophic
dystrophic (dis-trof′ik)

Relating to dystrophy.

dystrophin
dystrophin (dis-tro′fin)

A protein found in the sarcolemma of normal muscle; it is missing in individuals with pseudohypertrophic muscular dystrophy and in other forms of muscular dystrophy; its role may be in the linkage of the cytoskeleton of the muscle cell to extracellular protein. SYN: distropin, dystropin.

dystrophy
dystrophy (dis′tro-fe)

Progressive changes that may result from defective nutrition of a tissue or organ. SYN: dystrophia. [dys- + G. trophe, nourishment]
adiposogenital d. a disorder characterized primarily by obesity and hypogonadotrophic hypogonadism in adolescent boys; dwarfism is rare, and when present is thought to reflect hypothyroidism. Visual loss, behavioral abnormalities, and diabetes insipidus may occur. Fröhlich syndrome often is used synonymously for this disorder. Although the original case involved a pituitary tumor, most cases are thought to result from hypothalamic dysfunction in areas regulating appetite and gonadal development. The most common causes are pituitary and hypothalamic neoplasms. SYN: adiposis orchica, adiposogenital degeneration, adiposogenital syndrome, dystrophia adiposogenitalis, Fröhlich syndrome, hypophysial syndrome, hypothalamic obesity with hypogonadism, Launois-Cléret syndrome.
adult foveomacular retinal d. an autosomal dominant disorder presenting in the fifth decade with a mild decrease in vision and subfoveal, round yellow lesion with a central hyperpigmented spot.
adult pseudohypertrophic muscular d. [MIM*310200.0002] SYN: Becker muscular d..
anterior corneal d. corneal opacification with involvement of the epithelium, basement membrane, or Bowman membrane of the cornea.
asphyxiating thoracic d. [MIM*208500] hereditary hypoplasia of the thorax, associated with pelvic skeletal abnormality. SYN: asphyxiating thoracic chondrodystrophy, asphyxiating thoracic dysplasia, Jeune syndrome, thoracic-pelvic-phalangeal d..
Becker muscular d. a hereditary muscle disorder of late onset, usually in the second or third decade, affecting the proximal muscles with characteristic pseudohypertrophy of the calves; clinical features similar to Duchenne muscular d. but much milder and not a genetic lethal; X-linked recessive inheritance, with both Becker and Duchenne dystrophies caused by mutation in the dystrophin gene on Xp. Cf.:Duchenne d.. SYN: adult pseudohypertrophic muscular d., Becker-type tardive muscular d..
Becker-type tardive muscular d. SYN: Becker muscular d..
central areolar choroidal d. an autosomal dominant progressive disorder of vision loss with well-demarcated areas of atrophy of retinal pigment epithelium and choriocapillaris.
central cloudy corneal d. of François an autosomal dominant opacification of the central corneal stroma consisting of cloudy polygonal areas.
central crystalline corneal d. of Snyder an autosomal dominant opacification of the central corneal stroma by needle-shaped polychromatic crystals.
childhood muscular d. SYN: Duchenne d..
Cogan d. SYN: map-dot-fingerprint d..
cone d. a retinal abnormality in which color perception is severely deficient and typical changes occur in electroretinogram. See achromatopsia. SYN: cone degeneration.
cone-rod retinal d. a disorder affecting the retinal cones more than the rods, characterized by diminished central vision and color vision.
congenital hereditary endothelial d. a dominantly or recessively inherited condition characterized by a cloudy, thickened cornea at birth or in the neonatal period.
corneal d. [MIM*217600] central corneal opacification, usually bilateral, symmetrical, involving predominantly epithelial, stromal, or endothelial layers, often in a typical pattern; autosomal recessive inheritance.
craniocarpotarsal d. [MIM*193700] a syndrome characterized by specific facial features with sunken eyes, hypertelorism, long philtrum, small nose, and small mouth with pursing of lips as in whistling, and skeletal malformations with ulnar deviation of hands, camptodactyly, talipes equinovarus, and frontal bone defects; autosomal dominant inheritance. SYN: craniocarpotarsal dysplasia, Freeman-Sheldon syndrome, whistling face syndrome.
Duchenne d. the most common childhood muscular d., with onset usually before age 6. Characterized by symmetric weakness and wasting of first the pelvic and crural muscles and then the pectoral and proximal upper extremity muscles; pseudohypertrophy of some muscles, especially the calf; heart involvement; sometimes mild mental retardation; progressive course and early death, usually in adolescence. X-linked inheritance (affects males and transmitted by females). SYN: childhood muscular d., Duchenne disease, pseudohypertrophic muscular d..
Emery-Dreifuss muscular d. a generally benign type of muscular d., with onset in childhood or early adulthood. Weakness begins with the pectoral girdle and proximal upper extremity muscles and spreads to the pelvic girdle and distal lower extremity muscles. Contractures of the elbow, flexors, neck flexors, and calf muscles often occur; muscle pseudohypertrophy and mental retardation do not occur. A cardiomyopathy is common. An X-linked inherited disorder, nonallelic to Duchenne muscular d..
facioscapulohumeral muscular d. [MIM*158900] a highly variable hereditary disorder with onset in childhood or adolescence, characterized by weakness and wasting, sometimes asymmetrical, mainly of the muscles of the face, shoulder girdle, arms, and later, pelvic girdle and legs; autosomal dominant inheritance. SYN: facioscapulohumeral atrophy, Landouzy-Dejerine d..
Favre d. SYN: vitreotapetoretinal d..
fingerprint d. a condition wherein fine parallel lines in a fingerprint configuration area are seen in the basal epithelial layer and basement membrane of the corneal epithelium. SEE ALSO: map-dot-fingerprint d..
fleck d. of cornea [MIM*121850] a bilateral occurrence of subtle spots in the corneal stroma; the spots vary in size and shape, and have sharp margins and clear centers; photophobia may occur; autosomal dominant inheritance.
Fuchs endothelial d. common corneal d. with autosomal dominant inheritance, characterized by keratopathia guttata with loss of endothelium and progressive corneal edema.
gelatinous droplike corneal d. a bilateral, autosomal recessive condition characterized by mulberrylike elevated amyloid deposits involving the epithelium and anterior corneal stroma.
granular corneal d. an autosomal dominant disorder characterized by hyaline deposits in the corneal stroma.
Groenouw corneal d. 1. a granular type of corneal d., with autosomal dominant inheritance [MIM*121900], caused by mutation in the transforming growth factor, beta-induced, gene (TGFB1) encoding keratoepithelin on chromosome 5q; 2. a progressive macular type of corneal d., characterized by punctate opacities and episodes of photophobia, corneal erosion, and foreign body sensation; autosomal recessive inheritance.
gutter d. of cornea a marginal furrow usually inferiorly about 1 mm from the limbus; and sometimes bilateral. SYN: keratoleptynsis (1) .
hereditary epithelial d. SYN: Meesman d..
hypertrophic d. SYN: squamous cell hyperplasia.
infantile neuroaxonal d. a rare, familial disorder of early childhood manifested as progressive psychomotor deterioration, increased reflexes, Babinski sign, hypotonia and progressive blindness. Pathologically, eosinophilic spheroids of swollen axoplasm are found in various central nervous system nuclei.
Landouzy-Dejerine d. SYN: facioscapulohumeral muscular d..
lattice corneal d. [MIM*122200] a corneal d. due to localized accumulation of amyloid in a reticular pattern; manifest at puberty and progressing slowly until eventually useful vision is lost; autosomal dominant inheritance, caused by mutation in the transforming growth factor, beta-induced, gene (TGFB1) encoding keratoepithelin on 5q.
Leyden-Möbius muscular d. SYN: limb-girdle muscular d..
limb-girdle muscular d. [MIM*253600] a group of muscular dystrophies, probably heterogeneous in nature. Onset usually in childhood or early adulthood and both sexes affected. Characterized by weakness and wasting, usually symmetrical, of the pelvic girdle muscles, the shoulder girdle muscles, or both, but not the facial muscles. Muscle pseudohypertrophy, heart involvement, and mental retardation are absent. Autosomal dominant and recessive inheritance have been described. SYN: Leyden-Möbius muscular d., pelvofemoral muscular d., scapulohumeral muscular d..
macular corneal d. an autosomal recessive disorder characterized by glycosaminoglycan deposits in the corneal stroma.
macular retinal d. a group of disorders involving predominantly the posterior portion of the ocular fundus, due to degeneration in the sensory layer of the retina, retinal pigment epithelium, Bruch membrane, choroid, or a combination of these tissues. See Stargardt disease, Best disease.
map-dot-fingerprint d. fingerprint d. accompanied by maplike patterns and microcystic epithelial inclusions. SYN: Cogan d..
Meesman d. [MIM*122100] epithelial d. characterized by progressive cysts and opacities of the corneal epithelium, with onset in infancy; autosomal dominant inheritance with incomplete penetrance. SYN: hereditary epithelial d..
microcystic epithelial d. bilateral, symmetrical intraepithelial cysts in the central area of the cornea of healthy women, without hereditary predisposition.
mucopolysaccharide keratin d. a histologic finding seen in the surface epithelium of oral inflammatory fibrous hyperplasia, consisting of homogeneous eosinophilic pools of material in the superficial spinous layer.
muscular d. a general term for a number of hereditary, progressive degenerative disorders affecting skeletal muscles, and often other organ systems as well. SYN: myodystrophy, myodystrophia.
myotonic d. [MIM*160900] the most common adult muscular d., characterized by progressive muscle weakness and wasting of some of the cranial innervated muscles, as well as the distal limb muscles; other clinical features include myotonia, cataracts, hypogonadism, cardiac abnormalities, and frontal balding; onset usually in the the third decade; autosomal dominant inheritance caused by abnormal trinucleotide repeat expansion in the dystrophia myotonica protein kinase gene (DMPK) on chromosome 19q. This disorder demonstrates anticipation (increase in severity in successive generations because of successive amplification of the trinucleotide repeats); the severe congenital form is almost always confined to the offspring of affected women. SYN: dystrophia myotonica, myotonia atrophica, myotonia dystrophica, Steinert disease.
neuroaxonal d. a rare disorder that begins in the second year of life and is relentlessly progressive; clinically characterized initially by walking difficulties, weakness, and areflexia, later followed by corticospinal and pseudobulbar findings, blindness, loss of pain appreciation, and mental deterioration; pathologically, eosinophilic spheroids of swollen axoplasm are found in various central nuclei; autosomal recessive inheritance.
oculopharyngeal d. a dominantly inherited form of chronic progressive external ophthalmoplegia usually presenting in middle life or old age with chronic ptosis and/or difficulty swallowing. Many sufferers have French-Canadian ancestry.
pattern retinal d. a spectrum of autosomal dominant diseases affecting the retinal pigment epithelium, leading to mild to moderate vision loss.
pelvofemoral muscular d. SYN: limb-girdle muscular d..
posterior corneal d. opacification with primary involvement of the endothelium of the cornea.
posterior polymorphous corneal d. an autosomal dominant condition characterized by vesicular and linear abnormalities of the corneal endothelium; occasionally leads to corneal edema.
pre-Descemet corneal d. opacification with primary involvement of the posterior stroma of the cornea.
progressive tapetochoroidal d. SYN: choroideremia.
pseudohypertrophic muscular d. SYN: Duchenne d..
reflex sympathetic d. (RSD) diffuse persistent pain usually in an extremity often associated with vasomotor disturbances, trophic changes, and limitation or immobility of joints; frequently follows some local injury. SEE ALSO: causalgia. SYN: shoulder-hand syndrome, sympathetic reflex d..
Reis-Bücklers corneal d. an autosomal dominant disorder of Bowman membrane of the cornea, characterized by a reticular haze and associated with recurrent corneal erosions.
ringlike corneal d. [MIM*121900] threadlike opacities of the anterior corneal stroma, with acute, painful onset followed by decreased vision; autosomal dominant inheritance, caused by mutationin the transforming growth factor, beta-induced, gene (TGFB1) encoding keratoepithelium on chromosome 5q.
scapulohumeral muscular d. SYN: limb-girdle muscular d..
stromal corneal d. opacification with involvement of the middle layer of the cornea.
sympathetic reflex d. SYN: reflex sympathetic d..
thoracic-pelvic-phalangeal d. SYN: asphyxiating thoracic d..
twenty-nail d. longitudinal ridging of all of the nails; seen in alopecia areata and lichen planus.
vitelliform retinal d. SYN: Best disease.
vitreotapetoretinal d. [MIM*268100] autosomal recessive bilateral peripheral and central retinoschisis with pigmentary degeneration of the retina, chorioretinal atrophy, vitreous degeneration, and night blindness. SYN: Favre d..
vortex corneal d. a swirling pattern of abnormally pigmented corneal epithelial cells, seen in Fabry disease and in response to certain medications (including chloroquine, chlorpromazine, and amiodarone).
vulvar d. a spectrum of vulvar eruptions consisting of white atrophic papules, including lichen sclerosus et atrophicus, squamous cell hyperplasia (hypertrophic d.), or a combination of these (mixed d.). SEE ALSO: lichen sclerosus et atrophicus.

dystropin
dystropin

SYN: dystrophin.

dystropy
dystropy (dis′tro-pe)

Abnormal or eccentric behavior. [dys- + G. tropos, a turning]

dysuria
dysuria (dis-u′re-a)

Difficulty or pain in urination. SYN: dysury. [dys- + G. ouron, urine]

dysuric
dysuric (dis-u′rik)

Relating to or suffering from dysuria.

dysury
dysury (dis′u-re)

SYN: dysuria.

dysversion
dysversion (dis-ver′zhun)

A turning in any direction, less than inversion; particularly d. of the optic nerve head (situs inversus of the optic disk). [dys- + L. verto, to turn]

d-epirhamnose
d-epirhamnose (ep-i-ram′noz)

6-Deoxy-d-glucose;occurs in plants and bacteria in combination with diacylglycerol and is often sulfated (at C-6) in glycolipids. SYN: quinovose.

d-galacturonic acid
d-galacturonic acid (ga-lak-toor-on′ik)

The d-isomer is an oxidation product of d-galactose, in which the 6-CH₂OH group has become a –COOH group; occurs in many natural products ( e.g., pectins) and cell walls. SYN: pectic acid.

d-glucose
d-glucose (G, Glc) (gloo′kos)

Dextrose;a dextrorotatory monosaccharide (hexose) found in the free state in fruits and other parts of plants, and combined in glucosides, disaccharides (often with fructose in sugars), oligosaccharides, and polysaccharides; it is the product of complete hydrolysis of cellulose, starch, and glycogen. Free glucose also occurs in the blood, where it is a principal energy source for use by body tissues (normal human concentration, 70–110 mg per 100 mL); in diabetes mellitus, it appears in the urine. The epimers of d-glucose are d-allose, d-mannose, d-galactose, and l-idose. Dextrose should not be confused with the l-isomer, which is sinistrose. SYN: cellohexose.
activated glucose a nucleoside diphosphoglucose such as UDPglucose.
glucose dehydrogenase converts β-d-glucose to d-glucono-δ-lactone, transferring hydrogen to NAD⁺ or NADP⁺. Cf.:glucose oxidase.
liquid glucose a pharmaceutic aid consisting of dextrose, dextrins, maltose, and water, obtained by the incomplete hydrolysis of starch.
glucose oxidase an antibacterial flavoprotein enzyme, obtained from Penicillum notatum and other fungi, which is antibacterial only in the presence of glucose and oxygen, its effect being due to the oxidation of d-glucose to d-glucono-δ-lactone, with the coconversion of O₂ to H₂O₂; used in the preservation of food and in assays for glucose levels. SYN: glucose oxyhydrase, microcide.
glucose oxyhydrase SYN: glucose oxidase.
glucose phosphomutase SYN: phosphoglucomutase.

d-glucose 1,6-bisphosphate
d-glucose 1,6-bisphosphate

A bisphosphorylated derivative of d-glucose that is a required intermediate in the interconversion of d-glucose 1-phosphate and d-glucose 6-phosphate.

d-glucose 1-phosphate
d-glucose 1-phosphate

An important intermediate in glycogenesis and glycogenolysis. SYN: Cori ester.

d-glucose 6-phosphate
d-glucose 6-phosphate

A key intermediate in glycolysis, glycogenolysis, pentose phosphate shunt, etc.; elevated levels inhibit brain hexokinase and glycolysis. SYN: Robison ester, Robison-Embden ester.

d-glucuronolactone
d-glucuronolactone (gloo′ku-ro′no-lak′ton)

Used as a means of orally administering glucuronic acid in the management of collagen and joint diseases. SYN: glucurone.

d-glyceric aciduria
d-glyceric aciduria (gli-ser′ic as-id-oo-re-a)

1. Elevated levels of d-glyceric acid in the urine. 2. An inborn error in metabolism resulting in d-glyceric aciduria (1).

d-glycogenous
d-glycogenous (gli-koj′e-nus)

SYN: glycogenetic.

d-altro-2-heptulose
d-altro-2-heptulose

SYN: sedoheptulose.

d-manno-heptulose
d-manno-heptulose

A ketoheptose of the mannose configuration, occurring in the urine of individuals who have eaten a large quantity of avocados.

D-homosteroid
D-homosteroid (ho-mo-ster′oyd)

A steroid in which the D ring is made up of six carbon atoms instead of the usual five.

δ-hydroxylysine
δ-hydroxylysine

SYN: 5-hydroxylysine.

dl-hyoscyamine
dl-hyoscyamine

SYN: atropine.

d-sorbitol-6-phosphate dehydrogenase
d-sorbitol-6-phosphate dehydrogenase

An oxidoreductase that catalyzes the interconversion of d-sorbitol 6-phosphate and NAD⁺ to d-fructose 6-phosphate and NADH. A key step in fructose metabolism in the lens. SYN: ketose reductase.