N-acetylaspartate

N-acetylaspartate (as′-e-til-as-par′tat)

An acetylated derivative of aspartate found in the brain. Used as a marker in brain NMR and in neuroimaging.

N-acetylglucosamine
N-acetylglucosamine (as′e-til-glu-cos′a-men)

An acetylated amino sugar that is an important moiety of glycoproteins.

N-acetylglutamate
N-acetylglutamate (NAG) (a-se′til-gloo′ta-mat)

The salt of N-acetylglutamic acid. An activator of carbamoyl phosphate synthetase I during urea synthesis; this amino acid causes a configurational change in the enzyme, increasing the activity of that enzyme. The inability to synthesize acetylglutamate results in a defect in urea biosynthesis.

N-acetylneuraminic acid
N-acetylneuraminic acid (NeuAc) (as′e-til-nur-a-min′ik-as′id)

The most common form of sialic acid in mammals.

N4-acetylsulfanilamide
N⁴-acetylsulfanilamide (as′e-til-sul-fa-nil′a-mid)

An intermediate in the synthesis of sulfanilamide; formed in animal bodies by acetylation of sulfanilamide. SYN: p-sulfamylacetanilide.

N1-acetylsulfanilamide
N¹-acetylsulfanilamide

An antibacterial sulfa drug used topically and in the eye.

n-acylamino acid
n-acylamino acid (as-il-am′i-no)

An amino acid that has an acyl group attached to its N, as in hippuric acid (N-benzoylglycine) or phenaceturic acid.

N-acylsphingosine
N-acylsphingosine (as-il-sfing′go-sen)

A condensation product of an organic acid with sphingosine at the amino group of the latter compound.

N-allylnormorphine
N-allylnormorphine (al′il-nor-mor′fen)

SYN: nalorphine.

n-capric acid
n-capric acid (kap′rik)

A fatty acid found among the hydrolysis products of fat in goat's milk, cow's milk, and other substances. Cf.:n.caproic acid, caprylic acid. SYN: n-decanoic acid.

n-caproic acid
n-caproic acid (kap-ro′ik)

A fatty acid found among the hydrolysis products of fat in butter, coconut oil, and some other substances. SYN: n-hexanoic acid.

N-carbamoylaspartic acid
N-carbamoylaspartic acid (kar′ba-mo-il-as-par′tik)

SYN: ureidosuccinic acid.

N-carbamoylglutamic acid
N-carbamoylglutamic acid (kar′ba-mo-il-gloo-tam′ik)

An intermediate in the carbamoylation of ornithine to citrulline in the urea cycle; used in the treatment of individuals having a deficiency of the enzyme that synthesizes N-acetylglutamate.

N-carboxyanhydrides
N-carboxyanhydrides (kar-bok′se-an-hi′dridz)

Heterocyclic derivatives of amino acids from which polypeptides may be synthesized.

N-carboxyurea
N-carboxyurea (kar-bok′se-u-re′a)

SYN: allophanic acid.

n-decane
n-decane (dek′an)

A paraffin hydrocarbon, CH₃&cbond;(CH₂)₈&cbond;CH₃.

n-decanoic acid
n-decanoic acid (dek-a-no′ik)

SYN: n-capric acid.

N,N-dimethyltryptamine
N,N-dimethyltryptamine (DMT) (di-meth′il-trip′ta-men)

A psychotomimetic agent present in several South American snuffs ( e.g., cohoba snuff) and in the leaves of Prestonia amazonica (family Apocynaceae). Effects are similar to those of LSD, but with more rapid onset, greater likelihood of a panic reaction, and a shorter duration (1 to 2 hours, “businessman's trip”); it produces pronounced autonomic effects, including a marked increase in blood pressure.

n-docosanoic acid
n-docosanoic acid (do′ko-san-o′ik)

SYN: behenic acid.

n-dodecanoic acid
n-dodecanoic acid (do-dek′a-no-ik)

SYN: lauric acid.

n-eicosanoic acid
n-eicosanoic acid (i′ko-sa-no′ik)

SYN: arachidic acid.

N-formiminotetrahydrofolate
N-formiminotetrahydrofolate (for-mim′i-no-tet′ra-hi-dro-fo′lat)

A derivative of one-carbon tetrahydrofolate formed via l-histidine catabolism.

N-formylglycinamide ribotide
N-formylglycinamide ribotide (FGAR)

An intermediate in purine biosynthesis.

N-formylkynurenine
N-formylkynurenine (en-for′mil-ki-noor′e-nen)

The product of the oxidative cleavage of the indole ring in l-tryptophan; the intermediate first formed in l-tryptophan catabolism.

N-formylmethionine
N-formylmethionine (fMet) (for′mil-me-thi′o-nen)

Methionine acylated on the NH₂ group by a formyl (–CHO) group. This is the starting amino acid residue for virtually all bacterial polypeptides. It is also observed in mitochondria and chloroplasts of eukaryotes. SEE ALSO: initiating codon.

N10-formyltetrahydrofolate
N¹⁰-formyltetrahydrofolate

A formyl derivative of tetrahydrofolate that serves as a one-carbon source in metabolism.

N-glycoside
N-glycoside

Misnomer for glycosyl.

n-heptylpenicillin
n-heptylpenicillin (hep′til-pen-i-sil′in)

Penicillin K.

n-hexanoic acid
n-hexanoic acid (hek-sa-no′ik)

SYN: n-caproic acid.

n-icosanoic acid
n-icosanoic acid (i′ko-sa-no′ik)

SYN: arachidic acid.

N5,N10-methenyltetrahydrofolic acid
N⁵,N¹⁰-methenyltetrahydrofolic acid

SYN: anhydroleucovorin.

N5,N10-methenyltetrahydrofolate
N⁵,N¹⁰-methenyltetrahydrofolate

A one-carbon derivative of tetrahydrofolate; used in purine biosynthesis.

N-methyl d-aspartic acid
N-methyl d-aspartic acid

SYN: NMDA.

N-methylcarnosine
N-methylcarnosine (meth-il-kar′no-sen)

SYN: anserine (2) .

N5,N10-methylenetetrahydrofolate reductase
N⁵,N¹⁰-methylenetetrahydrofolate reductase

An enzyme that converts N⁵,N¹⁰-methylenetetrahydrofolate to N⁵,N¹⁰-methenyltetrahydrofolate using NADP⁺; a deficiency of this enzyme results in an accumulation of l-homocysteine and severe neurological disturbances.

N-methylglucamine
N-methylglucamine

SYN: methylglucamine.

N-methylhistidine
N-methylhistidine (meth′il-his′ti-den)

A methylated derivative of histidine found in actin; in the breakdown of actin and myosin, N-methylhistidine is released into the urine; urinary output of N-methylhistidine is a reliable index of the rate of myofibrillar protein breakdown in musculature.

N5-methyltetrahydrofolate
N⁵-methyltetrahydrofolate (meth-il-tet′ra-hi-dro-fol-at)

An active one-carbon derivative of tetrahydrofolate that participates in the S-methylation of l-homocysteine.
N⁵-methyltetrahydrofolate:homocysteine methyltransferase methionine synthase.

ν
ν

1. The 13th letter of the Greek alphabet, nu. 2. Symbol for kinematic viscosity; frequency; stoichiometric number. 3. In chemistry, denotes the position of a substituent located on the thirteenth atom from the carboxyl or other functional group.

N
N

1. Symbol for newton; nitrogen; asparagine; nucleoside; normal solution; haploid chromsome number. 2. Designation for an inherited blood factor. See MNSs blood group, Blood Groups appendix.

N/2
N/2

Symbol for seminormal.

15N
¹⁵N

Symbol for nitrogen-15.

14N
¹⁴N

Symbol for nitrogen-14.

13N
¹³N

Symbol for nitrogen-13.

NA
N_A

Symbol for Avogadro number.

n
n

Symbol for nano- (2) ; reaction order.

<SMCAP>n</SMCAP>
n

Symbol for normal concentration. See normal (3) .

n
n

1. The number in a scientific study. Sample size. 2. Symbol for refractive index.

n0
n₀

Abbreviation for Loschmidt number.

NA
NA

Abbreviation for Nomina Anatomica.

N.A.
N.A.

Abbreviation for numerical aperture.

Na
Na

Symbol for sodium (natrium).

24Na
²⁴Na

Symbol for sodium-24.

nabilone
nabilone (nab′i-lon)

A synthetic cannabinoid used in the treatment of nausea and vomiting associated with cancer chemotherapy.

Naboth
Naboth

Martin, German anatomist and physician, 1675–1721. See nabothian cyst, follicle.

nacreous
nacreous (na′kre-us)

Lustrous, like mother-of-pearl; descriptive term for bacterial colonies. [Fr. nacre, mother-of-pearl]

NAD
NAD

Abbreviation for nicotinamide adenine dinucleotide.

N.A.D.
N.A.D.

Abbreviation for no appreciable disease; nothing abnormal detected (British).

NAD+
NAD⁺

Abbreviation for nicotinamide adenine dinucleotide (oxidized form).
NAD⁺ nucleosidase an enzyme hydrolyzing NAD⁺ to nicotinamide and adenosine diphosphoribose. SYN: NADase.
NAD⁺ pyrophosphorylase an enzyme that participates in the synthesis of NAD⁺; it reacts nicotinamide mononucleotide with ATP to produce NAD⁺ and pyrophosphate; it will also act on nicotinate mononucleotide.
NAD⁺ synthetase an enzyme that catalyzes the reaction of ATP, l-glutamine, and nicotinate adenine dinucleotide to form NAD⁺, ADP, and l-glutamate.

NADase
NADase

SYN: NAD⁺ nucleosidase.

NADH
NADH

Abbreviation for nicotinamide adenine dinucleotide (reduced form).
N. dehydrogenase an iron-sulfur–containing flavoprotein reversibly oxidizing N. to NAD⁺; an inherited deficiency of this complex results in overwhelming acidosis. SYN: cytochrome c reductase.
N. dehydrogenase (quinone) an enzyme oxidizing N. with quinones ( e.g., menaquinone) as acceptors.
N.-hydroxylamine reductase an enzyme catalyzing the reaction of hydroxylamine and N. to form ammonia, NAD⁺, and water; used in a number of clinical assays.

nadide
nadide (na′did)

A nicotinamide adenine dinucleotide compound used as an antagonist to alcohol and narcotics.

nadir
nadir (na′der)

The lowest value of blood counts after chemotherapy. [M.E., Med. L., lowest point, fr. Arabic nazir, opposite (the zenith)]

Nadi reaction
Nadi reaction

See under reaction.

nadolol
nadolol (na′do-lol)

A β-adrenergic blocking agent with actions similar to those of propranolol.

NADP
NADP

Abbreviation for nicotinamide adenine dinucleotide phosphate.

NADP+
NADP⁺

Abbreviation for nicotinamide adenine dinucleotide phosphate (oxidized form).

NAD(P)+ nucleosidase
NAD(P)⁺ nucleosidase

An enzyme hydrolyzing NAD(P)⁺ to release free nicotinamide and adenosinediphosphoribose(phosphate).

NADPH
NADPH

Abbreviation for nicotinamide adenine dinucleotide phosphate (reduced form).
N.-cytochrome c₂ reductase an enzyme catalyzing the reduction of 2ferricytochrome c₂ to 2ferrocytochrome c₂ at the expense of N.. SYN: cytochrome c₂ reductase.
N. dehydrogenase a flavoprotein oxidizing N. to NADP⁺. SYN: N. diaphorase, old yellow enzyme, Warburg old yellow enzyme.
N. dehydrogenase (quinone) a flavoprotein oxidizing NADH or N. to NAD⁺ or NADP⁺ with quinones ( e.g., menadione) as hydrogen acceptors. SYN: DT-diaphorase, menadione reductase, phylloquinone reductase, quinone reductase.
N. diaphorase SYN: N. dehydrogenase.
N.-ferrihemoprotein reductase (fer′i-he-mo-pro′ten, fer′e-) an enzyme catalyzing the reduction of 2 ferricytochrome by N. to 2 ferrocytochrome; the physiologic acceptor is probably cytochrome P-450; hence, it has a role in steroid hydroxylations. SYN: cytochrome reductase.

Naegeli
Naegeli

Otto, Swiss physician, 1871–1938. See N. type of monocytic leukemia.

Naegeli
Naegeli

Oskar, Swiss physician, 1885–1959. See N. syndrome.

Naegleria
Naegleria (na-gle′re-a)

A genus of free-living soil, water, and sewage ameba (order Schizopyrenida, family Vahlkampfiidae) one species of which, N. fowleri, has been implicated as the causative agent of the rapidly fatal primary amebic meningoencephalitis. Infection has been traced to swimming pools (including indoor chlorinated pools); entry is by the nasal mucosa, from which the amebae reach the meninges and brain through the cribriform plate and olfactory nerves. Other soil amebae that have been implicated, although of far less epidemiologic significance, include the genera Acanthamoeba and Hartmanella, the latter being a suspected but unproved causative agent.

nafcillin
nafcillin (naf′sil′in)

A semisynthetic penicillin derived from 6-aminopenicillanic acid; resistant to penicillinase, and effective against Staphylococcus aureus.
n. sodium a penicillinase-resistant penicillin.

Naffziger
Naffziger

Howard C., U.S. surgeon, 1884–1961. See N. operation, N. syndrome.

naftifine hydrochloride
naftifine hydrochloride (naf′ti-fen)

A broad-spectrum antifungal agent used in the topical treatment of tinea infections.

NAG
NAG

Abbreviation for N-acetylglutamate.

nagana
nagana (nah-gah′nah)

An acute or chronic disease of cattle, dogs, pigs, horses, sheep, and goats in sub-Saharan Africa; marked by fever, anemia, and cachexia, varying in severity with the parasite and the host. A collective term for diseases caused by the protozoan parasites Trypanosoma brucei brucei, T. congolense, and T. vivax.

Nagel
Nagel

Willibald A., German ophthalmologist and physiologist, 1870–1911. See N. test.

Nägele
Nägele

Franz K., German obstetrician, 1777–1851. See N. obliquity, N. pelvis, N. rule.

Nägeli
Nägeli

Karl W. von, Swiss botanist, 1817–1891. See micelle.

Nageotte
Nageotte

Jean, French histologist, 1866–1948. See N. cells, under cell.

nail
nail (nal)

1. One of the thin, horny, translucent plates covering the dorsal surface of the distal end of each terminal phalanx of fingers and toes. A n. consists of corpus or body, the visible part, and radix or root at the proximal end concealed under a fold of skin. The underpart of the n. is formed from the stratum germinativum of the epidermis, the free surface from the stratum lucidum, the thin cuticular fold overlapping the lunula representing the stratum corneum. SYN: unguis [TA] , n. plate, onyx. 2. A slender rod of metal, bone, or other solid substance, used in operations to fasten together the fragments of a broken bone. [A.S. naegel]
egg shell n. SYN: hapalonychia.
half and half n. division of the n. by a transverse line into a proximal dull white part and a distal pink or brown part; seen in uremia.
Hippocratic nails the coarse, curved nails capping clubbed digits.
ingrown n. a toenail, one edge of which is overgrown by the nailfold, producing a pyogenic granuloma; due to faulty trimming of the toenails or pressure from a tight shoe. SYN: ingrowing toenail, onychocryptosis, unguis aduncus, unguis incarnatus.
Küntscher n. an intramedullary n. used for internal fixation of a fracture.
parrot-beak n. a markedly curved fingernail.
pincer n. transverse overcurvature of the n. that increases distally, causing the lateral borders of the n. to pinch the soft tissue with resulting tenderness; may result from a developmental anomaly or subungual exostosis.
racket n. a broad flat thumbnail resulting from a congenital shorter and wider distal phalanx of the thumb.
reedy n. a n. marked by longitudinal ridges and furrows.
shell n. n. dystrophy accompanying clubbing of digits in bronchiectasis, with excessive longitudinal curvature of the n. plate and atrophy of the n. bed and underlying bone.
Smith-Petersen n. a triflanged n. for internal fixation of a fracture of the neck of the femur.
spoon n. SYN: koilonychia.
yellow n. the complete or almost complete cessation of all n. growth, with thickening of the nails, increase in the convexity, loss of cuticles, and yellowing; the resulting onycholysis can cause loss of some of the nails; the condition is often associated with pulmonary disease but differs from clubbing in that the soft tissues are not hypertrophic. Lymphatic drainage may be reduced, even in the absence of lymphedema. SYN: yellow n. syndrome.

nailing
nailing (nal′ing)

Act of inserting or driving a nail into the ends of a fractured bone.

Najjar
Najjar

Victor A., U.S. physician and biochemist, *1914. See Crigler-N. syndrome.

Nakanishi
Nakanishi

Kazuhiro, Japanese physician, *1945. See N. stain.

nalbuphine hydrochloride
nalbuphine hydrochloride (nal-bu′fen)

A synthetic opioid analgesic chemically related to oxymorphone, a narcotic, and to naloxone, a narcotic antagonist, with both agonist and antagonist narcotic properties.

nalidixic acid
nalidixic acid (nal-i-dik′sik)

An orally effective antibacterial agent used in the treatment of genitourinary tract infections.

nalorphine
nalorphine (nal-or′fen)

An early antagonist of most of the depressant and stimulatory effects of morphine and related narcotic analgesics; precipitates severe withdrawal symptoms in morphine addicts, is used in the diagnosis of suspected morphine addiction, and counteracts the respiratory depression produced by morphine and related compounds; when administered in the absence of narcotics, n. has mild analgesic and respiratory depressant effects in nonaddicts; superseded by naloxone. SYN: N-allylnormorphine.

naloxone hydrochloride
naloxone hydrochloride (nal-ok′son)

A potent antagonist of endorphins and narcotics, including pentazocine; devoid of pharmacologic action when administered without narcotics.

naltrexone
naltrexone (nal-treks′on)

An orally active narcotic antagonist; devoid of pharmacologic action when administered in the absence of narcotics.

NAME
NAME

Acronym for nevi, atrial myxoma, myxoid neurofibromas, and ephilides. See N. syndrome.

NANDA
NANDA

Acronym for North American Nursing Diagnosis Association.

nandrolone
nandrolone (nan′dro-lon)

A semisynthetic, parenterally administered, anabolic, androgenic steroid.
n. decanoate an anabolic androgen.
n. phenpropionate a moderately long-acting synthetic anabolic androgen. SYN: n. phenylpropionate.
n. phenylpropionate SYN: n. phenpropionate.

nanism
nanism (nan′izm)

Obsolete term for dwarfism. [G. nanos; L. nanus, dwarf]
mulibrey n. (mu′li-bra) autosomal recessive disorder with defects of liver, brain, muscle, and eyes. [from muscle, liver, brain, and eyes]
renal n. infantile renal osteodystrophy.
symptomatic n. dwarfism with defects in bone, dentition, and sexual development.

Nannizzia
Nannizzia (na-niz′e-a)

A genus of ascomycetous fungi composed of Microsporum species in their perfect state.

nano- nano-

1. Combining form relating to dwarfism (nanism). 2. (n) Prefix used in the SI and metric systems to signify submultiples of one-billionth (10⁻⁹). [G. nanos, dwarf]

nanocephalia
nanocephalia (nan′o-se-fa′le-a)

SYN: microcephaly.

nanocephalous
nanocephalous, nanocephalic (nan-o-sef′a-lus, -se-fal′ik)

SYN: microcephalic.

nanocephaly
nanocephaly (nan-o-sef′a-le)

SYN: microcephaly. [nano- + G. kephale, head]

nanocormia
nanocormia (nan-o-kor′me-a)

SYN: microsomia. [nano- + G. kormos, trunk]

nanogram
nanogram (ng) (nan′o-gram)

One-billionth of a gram (10⁻⁹ g).

nanokatal
nanokatal (nkat) (nan-o-ka-tal′)

One-billionth of a katal (10⁻⁹ kat).

nanomelia
nanomelia (nan-o-me′le-a)

SYN: micromelia. [nano- + G. melos, limb]

nanometer
nanometer (nm) (nan-om′e-ter)

One-billionth of a meter (10⁻⁹ m).

nanophthalmia
nanophthalmia, nanophthalmos (nan-of-thal′me-a, -mos)

SYN: microphthalmos. [nano- + G. ophthalmos, eye]

Nanophyetus salmincola
Nanophyetus salmincola (na-no′fi-e-tus sal-min′ko-la)

A digenetic fish-borne fluke (family Nanophyetidae) of dogs and other fish-eating mammals; the vector of Neorickettsia helmintheca, the agent of salmon poisoning. SYN: Troglotrema salmincola.

Nanta
Nanta

See Gandy-N. disease.

nanukayami
nanukayami (na-noo-ka-yah′me)

SYN: n. fever.

nape
nape (nap)

SYN: nucha.

napex
napex (na′peks)

The area of the scalp just below the occipital protuberance.

naphazoline hydrochloride
naphazoline hydrochloride (na-faz′o-len, naf-az′-)

A sympathomimetic amine, used as a topical vasoconstrictor; available as n. nitrate, with the same uses. SYN: naphthazoline hydrochloride.

naphtha
naphtha (naf′tha)

SYN: petroleum benzin. [G.]
coal tar n. SYN: benzene.
wood n. SYN: methyl alcohol.

naphthalene
naphthalene (naf′tha-len)

A carcinogenic and toxic hydrocarbon obtained from coal tar; used for many syntheses in industry and in some moth repellents; n. can cause an attack of hemolytic anemia in individuals with a deficiency of glucose-6-phosphate dehydrogenase. SYN: naphthalin, tar camphor.

naphthalenol
naphthalenol (naf-thal′e-nol)

SYN: naphthol.

naphthalin
naphthalin (naf′tha-lin)

SYN: naphthalene.

naphthazoline hydrochloride
naphthazoline hydrochloride (naf-thaz′o-len)

SYN: naphazoline hydrochloride.

naphthol
naphthol (naf′thol)

A phenol of naphthalene, occurring in two forms: α-n., a dye intermediate used in cytochemistry for l-arginine localization; β-n., also known as isonaphthol, used as an anthelmintic and antiseptic. Both forms are also used in the manufacture of dyes, organic chemicals, and rubber products. SYN: naphthalenol.

naphtholate
naphtholate (naf′tho-lat)

A compound of naphthol in which the hydrogen in the hydroxyl radical is substituted by a base.

naphthol yellow S
naphthol yellow S [C.I. 10316]

An acid dye used as a stain for basic proteins in microspectrophotometry.

naphthoquinone
naphthoquinone (naf-tho-kwin′on)

1. A quinone derivative of naphthalene, reducible to naphthohydroquinone; 1,4-n. derivatives have vitamin K activity ( e.g., menaquinone). 2. A class of compounds containing the n. (1) structure.

naphthyl
naphthyl (naf′thil)

The radical of naphthalene, C₁₀H₇–.

napier
napier (na′pe-er)

SYN: neper. [John N., Scottish mathematician, 1550–1617]

naproxen
naproxen (na-prok′sen)

A nonsteroidal anti-inflammatory analgesic agent used in the treatment of rheumatoid conditions.

napsylate
napsylate (nap′si-lat)

USAN-approved contraction for 2-naphthalenesulfonate.

narceine
narceine (nar′se-en)

An alkaloid of opium; C₂₃H₂₇NO₈. Ethylnarceine is a narcotic, analgesic, and antitussive.

narcissism
narcissism (nar-sis′izm, nar′si-sizm)

1. A state in which one interprets and regards everything in relation to oneself and not to other persons or things. 2. Self-love, which may include sexual attraction toward onself. SEE ALSO: autoeroticism. SYN: self-love. [Narkissos, G. myth. char.]
primary n. in psychoanalysis, the original psychic energy embodied or invested in the ego.
secondary n. in psychoanalysis, the psychic energy once attached to external objects, but now withdrawn from those objects and reinvested in the ego.

narco- narco-

Stupor, narcosis. [G. narkoo, to benumb, deaden]

narcoanalysis
narcoanalysis (nar′ko-a-nal′i-sis)

Psychotherapeutic treatment under light anesthesia, originally used in acute combat cases during World War II; also has been used in the treatment of childhood trauma. SEE ALSO: narcotherapy. SYN: narcosynthesis.

narcohypnia
narcohypnia (nar-ko-hip′ne-a)

A general numbness sometimes experienced at the moment of waking. [narco- + G. hypnos, sleep]

narcohypnosis
narcohypnosis (nar′ko-hip-no′sis)

Stupor or deep sleep induced by hypnosis. [narco- + G. hypnos, sleep]

narcolepsy
narcolepsy (nar′ko-lep-se)

A sleep disorder that usually appears in young adulthood, consisting of recurring episodes of sleep during the day and often disrupted nocturnal sleep; frequently accompanied by cataplexy, sleep paralysis, and hypnagogic hallucinations; a genetically determined disease. SYN: Gélineau syndrome, paroxysmal sleep. [narco- + G. lepsis, seizure]

narcoleptic
narcoleptic (nar′ko-lep′-tik)

1. A sleep-inducing drug. 2. A person with narcolepsy.

narcosis
narcosis (nar-ko′sis)

General and nonspecific reversible depression of neuronal excitability, produced by a number of physical and chemical agents, usually resulting in stupor rather than in anesthesia (with which n. was once synonymous). [G. a benumbing]
CO₂ n. SYN: hypoventilation coma.
intravenous n. administration of opiate medication intravenously.
nitrogen n. 1. n. produced by nitrogenous materials such as occurs in certain forms of uremia and hepatic coma; 2. the stuporous condition characterized by disorientation and by loss of judgment and skill, attributed to an increased partial pressure of nitrogen in the inspired air of deep-sea divers during underwater operations. Commonly referred to as “rapture of the deep.” SYN: rapture of the deep.

narcosynthesis
narcosynthesis (nar-ko-sin′the-sis)

SYN: narcoanalysis.

narcotherapy
narcotherapy (nar-ko-thar′a-pe)

Psychotherapy conducted with the patient under the influence of a sedative or narcotic.

narcotic
narcotic (nar-kot′ik)

1. Originally, any drug derived from opium or opium-like compounds with potent analgesic effects associated with both significant alteration of mood and behavior and potential for dependence and tolerance. 2. More recently, any drug, synthetic or naturally occurring, with effects similar to those of opium and opium derivatives, including meperidine and fentanyl and its derivatives. 3. Capable of inducing a state of stuporous analgesia. [G. narkotikos, benumbing]

narcotism
narcotism (nar′ko-tizm)

1. Stuporous analgesia induced by a narcotic. 2. Addiction to a narcotic.

naris
naris, pl .nares (na′ris, -res) [TA]

Anterior opening to the nasal cavity. SYN: anterior n., external n., nostril, prenaris. [L.]
anterior n. SYN: n..
external n. SYN: n..
internal n. obsolete term for choanae.
posterior nares SYN: choanae.

NARP
NARP

Acronym for neuropathy, ataxia, retinitis pigmentosa syndrome, one of the inherited mitochondrial disorders, caused by a point mutation resulting in the substitution of a single amino acid in the mitochondrial DNA at position 8993. A more severe expression of the same point mutation manifests clinically as Leigh disease (q.v.).

narrowband
narrowband

A limited band of sound frequencies, as opposed to the wideband of frequencies also known as white noise; used to mask hearing in the nontest ear in hearing measurement.

nasal
nasal (na′zal)

Relating to the nose. SYN: rhinal. [L. nasus, nose]

nascent
nascent (nas′ent, na′sent)

1. Beginning; being born or produced. 2. Denoting the state of a chemical element at the moment it is set free from one of its compounds. [L. nascor, pres. p. nascens, to be born]

nasioiniac
nasioiniac (na′ze-o-in′e-ak)

Relating to the nasion and inion; denoting the distance in a straight line between the frontonasal suture and the external occipital protuberance.

nasion
nasion (na′ze-on) [TA]

A point on the skull corresponding to the middle of the nasofrontal suture. SYN: nasal point. [L. nasus, nose]

Nasmyth
Nasmyth

Alexander, London dentist, 1789–1849. See N. cuticle, N. membrane.

naso- naso-

The nose. [L. nasus]

nasoantral
nasoantral (na′zo-an′tral)

Relating to the nose and the maxillary sinus.

nasociliary
nasociliary

Relating to nose and eyelids. See n. nerve.

nasofrontal
nasofrontal (na-zo-frun′tal)

Relating to the nose and forehead, or to the nasal cavity and frontal sinuses.

nasogastric
nasogastric (na-zo-gas′trik)

Pertaining to or involving both the nasal passages and the stomach, as in n. intubation.

nasolabial
nasolabial (na-zo-la′be-al)

Relating to the nose and upper lip. [naso- + L. labium, lip]

nasolacrimal
nasolacrimal (na-zo-lak′ri-mal)

Relating to the nasal and the lacrimal bones, or to the nasal cavity and the lacrimal ducts.

naso-oral
naso-oral (na-zo-o′ral)

Relating to the nose and mouth.

nasopalatine
nasopalatine (na′zo-pal′a-ten, -tin)

Relating to the nose and the palate.

nasopharyngeal
nasopharyngeal (na′zo-fa-rin′je-al)

Relating to the nose or nasal cavity and the pharynx. SYN: rhinopharyngeal (1) .

nasopharyngolaryngoscope
nasopharyngolaryngoscope (na′zo-fa-ring′go-la-ring′go-skop)

An instrument, often of fiberoptic type, used to visualize the upper airways and pharynx.

nasopharyngoscope
nasopharyngoscope (na′zo-fa-ring′go-skop)

Telescopic instrument, electrically lighted, for examination of the nasal passages and the nasopharynx.

nasopharyngoscopy
nasopharyngoscopy (na′zo-fa-ring-gos′ko-pe)

Examination of the nasopharynx by flexible or rigid optical instruments, or with a mirror. [nasopharynx + G. skopeo, to view]

nasopharynx
nasopharynx (na′zo-far′ingks) [TA]

The part of the pharynx that lies above the soft palate; anteriorly it opens into the nasal cavities via the choanae; inferiorly, it communicates with the oropharynx via the pharyngeal isthmus; laterally it communicates with tympanic cavities via pharyngotympanic (auditory) tubes. SYN: pars nasalis pharyngis [TA] , epipharynx, nasal part of pharynx, nasal pharynx, pharyngonasal cavity, rhinopharynx.

nasorostral
nasorostral (na′zo-ros′tral)

Relating to the nasal cavity and the rostrum of the sphenoid bone.

nasosinusitis
nasosinusitis (na′zo-si-nu-si′tis)

Inflammation of the nasal cavities and of the accessory sinuses.

Nasse
Nasse

Christian Friedrich, German physician, 1788–1851.

Nasse law
Nasse law

See under law.

nasus
nasus (na′sus)

1. SYN: external nose. 2. SYN: nose. [L.]
n. externus SYN: external nose.

natal
natal (na′tal)

1. Relating to birth. [L. natalis, fr. nascor, pp. natus, to be born] 2. Relating to the buttocks or nates. [L. nates, buttocks]

natality
natality (na-tal′i-te)

The birth rate; the ratio of births to the general population. [see natal (1)]

natamycin
natamycin (na-ta-mi′sin)

SYN: pimaricin.

nates
nates (na′tez) [TA]

SYN: buttocks. [L. pl. of natis]

National Formulary
National Formulary (NF)

An official compendium formerly issued by the American Pharmaceutical Association but now published by the United States Pharmacopeial Convention for the purpose of providing standards and specifications which can be used to evaluate the quality of pharmaceuticals and therapeutic agents.

natremia
natremia, natriemia (na-tre′me-a, na′tre-e′me-a)

The presence of sodium in the blood. [natrium, sodium, + G. haima, blood]

natrexone hydrochloride
natrexone hydrochloride (na-treks′on)

An orally active narcotic antagonist used in maintenance therapy of detoxified, formerly opioid-dependent, patients.

natriferic
natriferic (na-trif′er-ik)

Tending to increase sodium transport. [natrium + L. fero, to carry]

natrium
natrium (Na) (na′tre-um)

SYN: sodium. [Ar. natrum, fr. G. nitron, carbonate of soda]

natriuresis
natriuresis (na′tre-u-re′sis)

Urinary excretion of sodium; commonly designates enhanced sodium excretion, which may occur in certain diseases or as a result of the administration of diuretic drugs. [natrium + G. ouron, urine]

natriuretic
natriuretic (na′tre-u-ret′ik)

1. Pertaining to or characterized by natriuresis. 2. A substance that increases urinary excretion of sodium, usually as a result of decreased tubular reabsorption of sodium ions from glomerular filtrate.

Nattrassia mangiferae
Nattrassia mangiferae

A dematiaceous mold, previously known as Hendersonula toruloidea, that causes onychomycosis and phaeohyphomycosis. Scytalidium dimidiatum is a synanamorph. SYN: Hendersonula toruloidea.

naturopath
naturopath (na′choor-o-path)

One who practices naturopathy.

naturopathic
naturopathic (na′choor-o-path′ik)

Relating to or by means of naturopathy.

naturopathy
naturopathy (na-choor-op′a-the)

A system of therapeutics in which neither surgical nor medicinal agents are used, dependence being placed only on natural (nonmedicinal) forces.

naupathia
naupathia (naw-path′e-a)

SYN: seasickness. [G. naus, ship, + pathos, suffering]

nausea
nausea (naw′ze-a, -zha)

An inclination to vomit. SYN: sicchasia (1) . [L. fr. G. nausia, seasickness, fr. naus, ship]
epidemic n. SYN: epidemic vomiting.
n. gravidarum SYN: morning sickness.

nauseant
nauseant (naw′ze-ant)

1. Nauseating; causing nausea. 2. An agent that causes nausea.

nauseate
nauseate (naw′ze-at)

To cause an inclination to vomit.

nauseated
nauseated (naw′ze-a-ted)

Affected with nausea. SYN: sick (2) .

nauseous
nauseous (naw′ze-us, naw′shus)

1. Nauseated. 2. Causing nausea.

Nauta
Nauta

Walle J.H., U.S. neuroscientist, *1916. See N. stain.

navel
navel (na′vel)

SYN: umbilicus. [A.S. nafela]

navicula
navicula (na-vik′u-la)

A small boat-shaped structure. [L. dim of navis, ship]

navicular
navicular (na-vik′u-lar) [TA]

Flattened, medially placed tarsal bone, concave on its posterior surface to accommodate the head of the talus, and convex on its anterior surface to articulate with the three cuneiform bones. SYN: os naviculare [TA] , central bone of ankle, n. (bone), os centrale tarsi. [L. navicularis, relating to shipping]

Nb
Nb

Symbol for niobium.

NBT
NBT

Abbreviation for nitroblue tetrazolium.

Nd
Nd

Symbol for neodymium.

NDP
NDP

Abbreviation for nucleoside diphosphate.

Ne
Ne

Symbol for neon.

nearsightedness
nearsightedness (ner′sit-ed-nes)

SYN: myopia.

nearthrosis
nearthrosis (ne-ar-thro′sis)

A new joint; e.g., a pseudarthrosis arising in an ununited fracture, or an artificial joint resulting from a total joint replacement operation. SYN: neoarthrosis. [G. neos, new, + arthrosis, a jointing]

nebramycin
nebramycin (neb-ra-mi′sin)

A complex of substances produced by Streptomyces tenebrarius; an antibacterial agent.

nebul.
nebul.

Abbreviation for n..

nebula
nebula (nebul.) , pl .nebulae (neb′u-la, -le)

1. A translucent foglike opacity of the cornea. 2. A class of oily preparations, intended for application by atomization. See spray. 3. A spray. [L. fog, cloud, mist]

nebularine
nebularine (neb-u-lar′in)

A toxic nucleoside isolated from the mushroom Agaricus nebularis and from Streptomyces sp. SYN: 9-β-ribofuranosylpurine, purine ribonucleoside, ribosylpurine.

nebulin
nebulin (neb′u-lin)

A very large protein, constituting about 3% of skeletal muscle protein; may aid in the organization of actin filaments as well as in actin polymerization. [L. nebula, mist, fog, fr. G. nephele, + -in]

nebulization
nebulization (neb′u-li-za′shun)

Spraying or vaporization. [L. nebula, mist]

nebulize
nebulize (neb′u-liz)

To break up a liquid into a fine spray or vapor; to vaporize. [L. nebula, mist]

nebulizer
nebulizer (neb′u-liz-er)

A device used to reduce liquid medication to extremely fine cloudlike particles; useful in delivering medication to deeper parts of the respiratory tract. SEE ALSO: atomizer, vaporizer.
jet n. an atomizer that uses an air or gas stream to change a liquid into small particles.
spinning disk n. a n. in which water is changed into small particles as it is thrown by centrifugal force from a spinning disk.
ultrasonic n. a humidifier using high-frequency electricity to power a transducer that vibrates 1,350,000 times per second and changes water up into particles 0.5–3 μm in size in its nebulizing chamber; used in inhalation therapy.

Necator
Necator (ne-ka′tor)

A genus of nematode hookworms (family Ancylostomatidae, subfamily Necatorinae) distinguished by two chitinous cutting plates in the buccal cavity and fused male copulatory spicules. Species include N. americanus, the so-called New World hookworm (although it is also prevalent in the tropics of Africa, southern Asia, and Polynesia); the adults of this species attach to villi in the small intestine and suck blood, causing abdominal discomfort, diarrhea (usually with melena) and cramps, anorexia, loss of weight, and hypochromic microcytic anemia, which may occur in advanced disease. SEE ALSO: Ancylostoma. [L. a murderer]

necatoriasis
necatoriasis (ne-ka-to-ri′a-sis)

Hookworm disease caused by Necator, the resulting anemia being usually less severe than that from ancylostomiasis.

neck
neck (nek) [TA]

1. Part of body by which the head is connected to the trunk: it extends from the base of the cranium to the top of the shoulders. 2. In anatomy, any constricted portion having a fancied resemblance to the n. of an animal. 3. The germinative portion of an adult tapeworm which develops the segments or proglottids; the region of cestode segmentation behind the scolex. SYN: cervix (1) [TA] , collum&star. [A.S. hnecca]
anatomical n. of humerus [TA] a groove separating the head of the humerus from the tuberosities, giving attachment to the articular capsule. SYN: collum anatomicum humeri [TA] .
buffalo n. combination of moderate kyphosis with thick heavy fat pad on the n., seen especially in persons with Cushing disease or syndrome.
bull n. a heavy thick n. caused by hypertrophied muscles or enlarged cervical lymph nodes.
dental n. SYN: n. of tooth.
n. of femur [TA] a short, constricted, strong bar projecting at an obtuse angle (about 125°) from the upper end of the shaft of the thigh bone and supporting its head. SYN: collum femoris [TA] , collum ossis femoris, n. of thigh bone.
n. of fibula [TA] the slightly constricted region between the head and body of the fibula. SYN: collum fibulae [TA] .
n. of gallbladder [TA] the narrow portion between the body of the gallbladder and beginning of the cystic duct. SYN: collum vesicae biliaris [TA] , collum vesicae felleae&star.
n. of glans [TA] a constriction behind the corona of the glans penis. SYN: collum glandis [TA] .
n. of hair follicle the narrowed part of the hair follicle between the hair bulb and the surface of the skin. SYN: collum folliculi pili.
n. of humerus anatomical n. of humerus, surgical n. of humerus.
Madelung n. multiple symmetric lipomatosis (Madelung disease) confined to the n..
n. of malleus [TA] the constricted portion of the malleus between the head and the manubrium. SYN: collum mallei [TA] .
n. of mandible [TA] the constricted portion of the condylar process below the head of the mandible. SYN: collum mandibulae [TA] .
n. of pancreas [TA] segment of pancreas, approximately 2 cm long, connecting head and body of pancreas; it intervenes between the duodenum anteriorly and the junction of the splenic and superior mesenteric veins, forming the beginning of the portal vein, posteriorly. SYN: collum pancreaticus [TA] .
n. of radius [TA] the narrow part of the shaft just below the head. SYN: collum radii [TA] .
n. of rib [TA] the flattened portion of a rib between the head and the tuberosity. SYN: collum costae [TA] .
n. of scapula [TA] a slight constriction marking the separation of that portion bearing the glenoid cavity and coracoid process from the remainder of the scapula. SYN: collum scapulae [TA] .
stiff n. nonspecific term for limited n. mobility, often due to muscle cramps and accompanied by pain.
surgical n. of humerus [TA] the narrow portion below the head and tuberosities. SYN: collum chirurgicum humeri [TA] .
n. of talus [TA] a constriction separating the head, or anterior portion, from the body of the talus. SYN: collum tali [TA] .
n. of thigh bone SYN: n. of femur.
n. of tooth [TA] the slightly constricted part of a tooth, between the crown and the root. SYN: cervix dentis [TA] , cervix of tooth&star, cervical margin of tooth, cervical zone of tooth, collum dentis, dental n..
turkey gobbler n. large skin folds hanging under the chin.
n. of (urinary) bladder [TA] the lowest part of the bladder formed by the junction of the fundus and the inferolateral surfaces. SYN: cervix vesicae urinariae [TA] , collum vesicae&star.
n. of uterus SYN: cervix of uterus.
webbed n. the broad n. due to lateral folds of skin extending from the clavicle to the head but containing no muscles, bones, or other structures; occurs in Turner syndrome and in Noonan syndrome.
n. of womb SYN: cervix of uterus.
wry n. SYN: torticollis.

necklace
necklace (nek′las)

Term used to describe a skin rash that encircles the neck.
Casal n. a dermatitis partly or completely encircling the lower part of the neck in pellagra.

necr- necr-

See necro-.

necrectomy
necrectomy (ne-krek′to-me)

Operative removal of any necrosed tissue. [necr- + G. ektome, excision]

necro- necro-, necr-

Death, necrosis. [G. nekros, corpse]

necrobacillosis
necrobacillosis (nek′ro-bas-il-o′sis)

Any disease with which the bacterium Fusobacterium necrophorum is associated.

necrobiosis
necrobiosis (nek′ro-bi-o′sis)

1. Physiologic or normal death of cells or tissues as a result of changes associated with development, aging, or use. 2. Necrosis of a small area of tissue. [necro- + G. bios, life]
n. lipoidica, n. lipoidica diabeticorum a condition, in many cases associated with diabetes, in which one or more yellow, atrophic, shiny lesions develop on the legs (typically pretibial); characterized histologically by indistinct areas of necrosis in the cutis.

necrobiotic
necrobiotic (nek′ro-bi-ot′ik)

Pertaining to or characterized by necrobiosis.

necrocytosis
necrocytosis (nek′ro-si-to′sis)

A process that results in, or a condition that is characterized by, the abnormal or pathologic death of cells. [necro- + G. kytos, cell, + -osis, condition]

necrogenic
necrogenic (nek-ro-jen′ik)

Relating to, living in, or having origin in dead matter. SYN: necrogenous. [necro- + G. genesis, origin]

necrogenous
necrogenous (ne-kroj′e-nus)

SYN: necrogenic.

necrogranulomatous
necrogranulomatous (nek′ro-gran-u-lo′ma-tus)

Obsolete term for the characteristics of a granuloma with central necrosis.

necrologist
necrologist (ne-krol′o-jist)

A student of, or a specialist in, necrology.

necrology
necrology (ne-krol′o-je)

The science of the collection, classification, and interpretation of mortality statistics. [necro- + G. logos, study]

necrolysis
necrolysis (ne-krol′i-sis)

Necrosis and loosening of tissue. [necro- + G. lysis, loosening]
toxic epidermal n. (TEN) a syndrome in which a large portion of the skin becomes intensely erythematous with epidermal necrosis, and peels off in the manner of a second-degree burn, often simultaneous with the formation of flaccid bullae, resulting from drug sensitivity or of unknown cause; the level of separation is subepidermal, unlike staphylococcal scalded skin syndrome in which there is subcorneal change. SYN: Lyell syndrome.

necromania
necromania (nek-ro-ma′ne-a)

1. A morbid tendency to dwell with longing on death. 2. A morbid attraction to dead bodies. [necro- + G. mania, frenzy]

necrometer
necrometer (ne-krom′e-ter)

An instrument for measuring a dead body or any of its parts or organs. [necro- + G. metron, measure]

necroparasite
necroparasite (nek-ro-par′a-sit)

SYN: saprophyte.

necropathy
necropathy (ne-krop′a-the)

A tendency to tissue death or gangrene. [necro- + G. pathos, disease]

necrophagous
necrophagous (ne-krof′a-gus)

1. Living on carrion. 2. SYN: necrophilous. [necro- + G. phago, to eat]

necrophilia
necrophilia, necrophilism (nek-ro-fil′e-a, ne-krof′i-lizm)

1. A morbid fondness for being in the presence of dead bodies. 2. The impulse to have sexual contact, or the act of such contact, with a dead body, usually of males with female corpses. [necro- + G. phileo, to love]

necrophilous
necrophilous (ne-krof′i-lus)

Having a preference for dead tissue; denoting certain bacteria. SYN: necrophagous (2) . [necro- + G. philos, fond]

necrophobia
necrophobia (nek-ro-fo′be-a)

Morbid fear of corpses. [necro- + G. phobos, fear]

necropsy
necropsy (nek′rop-se)

SYN: autopsy (1) . [necro- + G. opsis, view]

necrosadism
necrosadism (nek-ro-sad′izm)

Sexual gratification derived by mutilating corpses. [necro- + sadism]

necroscopy
necroscopy (ne-kros′ko-pe)

Rarely used term for autopsy. [necro- + G. skopeo, to examine]

necrose
necrose (ne-kroz′)

1. To cause necrosis. 2. To become the site of necrosis.

necrosectomy
necrosectomy (ne-kro′sek-to-me)

Resection of necrotic tissue.

necrosis
necrosis (ne-kro′sis)

Pathologic death of one or more cells, or of a portion of tissue or organ, resulting from irreversible damage; earliest irreversible changes are mitochondrial, consisting of swelling and granular calcium deposits seen by electron microscopy; most frequent visible alterations are nuclear: pyknosis, shrunken and abnormally dark basophilic staining; karyolysis, swollen and abnormally pale basophilic staining; or karyorrhexis, rupture and fragmentation of the nucleus. After such changes, the outlines of individual cells are indistinct, and affected cells may become merged, sometimes forming a focus of coarsely granular, amorphous, or hyaline material. [G. nekrosis, death, fr. nekroo, to make dead]
acute massive liver n. a lesion in which there is extensive and rapid death of parenchymal cells of the liver, sometimes with fatty degeneration of the size of the organ; the n. may result from fulminant viral infection or chemical poisoning; associated with jaundice. SYN: acute parenchymatous hepatitis, acute yellow atrophy of the liver, Rokitansky disease (1) .
acute retinal n. (ARN) a viral syndrome occurring in immunocompetent patients, characterized by peripheral retinal destruction that becomes circumferential and leads to retinal detachment.
aseptic n. n. occurring in the absence of infection.
avascular n. n. due to deficient blood supply.
bridging hepatic n. area of liver n. that bridges adjacent portal areas and central veins; subsequent postnecrotic collapse and fibrosis is likely to result in cirrhosis.
caseous n., caseation n. n. characteristic of certain inflammations ( e.g., tuberculosis, histoplasmosis), which represents n. with loss of separate structures of the various cellular and histologic elements; affected tissue manifests the friable, crumbly consistency and dull, opaque quality observed in cheese. SYN: caseous degeneration.
central n. n. involving the deeper or inner portions of a tissue, or an organ or its units.
coagulation n. a type of n. in which the affected cells or tissue are converted into a dry, dull, fairly homogeneous eosinophilic mass without nuclear staining, as a result of the coagulation of protein as occurs in an infarct; microscopically, the necrotic process involves chiefly the cells, and remnants of histologic elements ( e.g., elastin, collagen, muscle fibers) may be recognizable, as well as “ghosts” of cells and portions of cell membranes; may be caused by heat, ischemia, and other agents that destroy tissue, including enzymes that would continue to alter the devitalized cellular substance.
colliquative n. obsolete term for liquefactive n..
contraction band n. SYN: contraction band.
cystic medial n. loss of elastic and muscle fibers in the aortic media, with accumulation of mucopolysaccharide, sometimes in cystlike spaces between the fibers; a disease of unknown cause, which may be inherited and which predisposes to dissecting aneurysms. SYN: Erdheim disease, medionecrosis aortae idiopathica cystica, medionecrosis of the aorta, mucoid medial degeneration.
epiphysial aseptic n. aseptic n. of bony epiphyses in children or adults probably due to ischemia; it may affect the upper end of the femur (Legg-Calvé-Perthes disease), the tibial tubercle (Osgood-Schlatter disease), the tarsal navicular bone or the patella (Köhler disease), the second metatarsal head (Freiberg disease), vertebral bodies (Scheuermann disease), or the capitellum of the humerus (Panner disease).
fat n. the death of adipose tissue, characterized by the formation of small (1–4 mm), dull, chalky, gray or white foci; these represent small quantities of calcium soaps formed in the affected tissue when fat is hydrolyzed into glycerol and fatty acids. SYN: steatonecrosis.
fibrinoid n. n. in which the necrotic tissue has some staining reactions resembling fibrin and becomes deeply eosinophilic, homogenous, and refractile.
focal n. occurrence of numerous, relatively small or tiny, fairly well-circumscribed, usually spheroidal portions of tissue that manifest coagulative, caseous, or gummatous n. and are characteristically associated with agents that are hematogenously disseminated; frequently observed only in histologic sections, but the foci may be as large as 1–3 mm and macroscopically visible; arbitrarily, foci larger than that are usually not termed focal n..
ischemic n. n. caused by hypoxia resulting from local deprivation of blood supply, as by infarction.
laminar cortical n. the breaking down of a definite cell layer in the cerebral cortex, encountered typically after temporary cardiac arrest or perinatal hypoxia.
liquefactive n. a type of n. characterized by a fairly well-circumscribed, microscopically or macroscopically visible lesion that consists of the dull, opaque or turbid, gray-white to yellow-gray, soft or boggy, partly or completely fluid remains of tissue that became necrotic and was digested by enzymes, especially proteolytic enzymes liberated from disintegrating leukocytes; it is classically observed in abscesses, and frequently in infarcts of the brain.
progressive emphysematous n. SYN: gas gangrene.
progressive outer retinal n. (PORN) a viral syndrome occurring in AIDS patients, caused by herpesvirus and characterized by destruction of peripheral retina.
renal papillary n. n. of renal papillae, occurring in acute pyelonephritis, especially in diabetics, or in analgesic nephropathy; renal failure may result. SYN: necrotizing papillitis.
simple n. a stage of coagulation n.; the occurrence of a coarsely granular or hyaline change in the cytoplasm, and the lack of a recognizable nucleus, with the general configuration of the dead cells being relatively unchanged.
subcutaneous fat n. of newborn indurated plaques and nodules appearing usually a few days or a few weeks after birth and usually resolving within a few months, characterized microscopically by birefringent needle-shaped crystals within necrotic fat cells; the condition remains localized, unlike sclerema neonatorum, although hypercalcemia may develop.
suppurative n. liquefactive n. with pus formation.
total n. 1. complete n. of the cytologic and histologic elements in a portion of tissue, as in caseous n.; 2. death of an entire organ or part.
zonal n. n. predominantly affecting or limited to an anatomical zone, especially parts of the hepatic lobules defined according to proximity to either the portal tracts or central (hepatic) veins.

necrospermia
necrospermia (nek-ro-sper′me-a)

A condition in which there are dead or immobile spermatozoa in the semen. [necro- + G. sperma, seed]

necrosteon
necrosteon, necrosteosis (ne-kros′te-on, ne-kros-te-o′sis)

Gangrene of bone. [necro- + G. osteon, bone]

necrotic
necrotic (ne-krot′ik)

Pertaining to or affected by necrosis.

necrotomy
necrotomy (ne-krot′o-me)

1. SYN: dissection. 2. Operation for the removal of a necrosed portion of bone (sequestrum). [necro- + G. tome, cutting]
osteoplastic n. removal of a bone sequestrum through a hinged window of bone which is then replaced.

needle
needle (ne′dl)

1. A slender, solid, usually sharp-pointed instrument used for puncturing tissues, suturing, or passing a ligature around or through a vessel. 2. A hollow n. used for injection, aspiration, biopsy, or to guide introduction of a catheter into a vessel or other space. 3. To separate the tissues by means of one or two needles, in the dissection of small parts. 4. To perform discission of a cataract by means of a knife n.. [M.E. nedle, fr. A.S. naedl]
aneurysm n., artery n. a blunt-pointed, curved n., set in a handle, with the eye at the point, used for passing a ligature around an artery.
aspirating n. a hollow n. used for withdrawing fluid from a cavity, when combined with an aspirator tube attached to one end.
atraumatic n. an eyeless surgical n. with the suture permanently fastened into a hollow end.
biopsy n. a hollow n. used to obtain a core of tissue for histologic study.
cataract n. SYN: knife n..
cutting n. a surgical n. with angulated surface designed to puncture tough tissue.
Deschamps n. a n. with a long shaft for passing sutures in the deep tissues.
Emmet n. a strong n. with the eye in the point, having a wide curve, and set in a handle, used to pass a ligature around an undissected structure.
exploring n. a strong n. with a longitudinal groove, which is thrust into a tumor or cavity to determine the presence of fluid, the latter escaping along the groove.
Francke n. a small lancet-shaped, spring-activated n., used to evacuate a small effusion of blood.
Frazier n. a n. for draining lateral ventricles of brain.
Gillmore n. a device for obtaining the setting time of dental cement.
Hagedorn n. a curved surgical n. flattened on the sides.
hypodermic n. a hollow n., similar to but smaller than an aspirating n., attached to a syringe; used primarily for injection.
knife n. a very narrow, n.-pointed knife used in discission of a cataract. SYN: cataract n..
lumbar puncture n. a n., provided with a stylet, for entering the spinal canal or cisterna magna, with a bore of at least 1 mm and 40 mm or more in length.
Millner n. a fine, non-cutting n. with eye for thread frequently used for suture of skin.
Salah sternal puncture n. a wide-bore n. for obtaining samples of red marrow from the sternum.
spatula n. a minute n. with a flat (noncutting) concave surface, used by eye surgeons.
stop-n. a surgical n., with the eye at the tip, the shank of which has a projecting shelf to arrest the n. when it has passed the desired distance through the tissues.
Tuohy n. a n. with a lateral opening at the distal end, designed to cause a catheter passing through the n.'s lumen to exit laterally at a 45° angle; used to place catheters into the subarachnoid or epidural space.
Veress n. a n. equipped with a spring loaded obturator that is used for insufflation of the abdomen in laparoscopic surgery.

needle-holder
needle-holder, needle-carrier, needle-driver

A hand-held instrument for grasping a needle in suturing. SYN: needle forceps.

Needles
Needles

J.W., U.S. dentist. See N. split cast method.

Needles
Needles

Carl F., U.S. pediatrician, *1935. See Melnick-N. osteodysplasty, Melnick-N. syndrome.

needling
needling (ned′ling)

Discission of a soft or secondary cataract.

Neelsen
Neelsen

Friedrich K.A., German pathologist, 1854–1894. See Ziehl-N. stain.

neencephalon
neencephalon (ne-en-sef′a-lon)

Edinger term for the higher levels of the central nervous system superimposed upon the metameric or propriospinal system (paleencephalon). SYN: neoencephalon. [G. neos, new, + enkephalos, brain]

NEEP
NEEP

Abbreviation for negative end-expiratory pressure.

nefopam hydrochloride
nefopam hydrochloride (nef′o-pam)

An analgesic agent.

Neftel
Neftel

William B., U.S. neurologist, 1830–1906.

negation
negation (ne-ga′shun)

SYN: denial.

negative
negative (neg′a-tiv)

1. Not affirmative; refutative; not positive; not abnormal. 2. Denoting failure of response, absence of a reaction, or absence of an entity or condition in question. [L. negativus, fr. nego, to deny]

negative G
negative G

Gravity in a foot-to-head direction in flying, or in standing on one's head; opposite of positive G.

negative S
negative S

SYN: flotation constant.

negativism
negativism (neg′a-tiv-izm)

A tendency to do the opposite of what one is requested to do, or to stubbornly resist for no apparent reason; seen in catatonic states and in toddlers.

negatron
negatron (neg′a-tron)

Term used for an electron to emphasize its negative charge in contradistinction to the positive charge carried by the otherwise similar positron.

Negri
Negri

Adelchi, Italian physician, 1876–1912. See N. bodies, under body, N. corpuscles, under corpuscle.

Negro
Negro

Camillo, Italian neurologist, 1861–1927. See N. phenomenon.

Neisser
Neisser

Albert L.S., German physician, 1855–1916. See Neisseria, N. coccus, N. syringe.

Neisser
Neisser

Max, German bacteriologist, 1869–1938. See N. stain.

Neisseria
Neisseria (ni-se′re-a)

A genus of aerobic bacteria (family Neisseriaceae) containing Gram-negative cocci which occur in pairs with the adjacent sides flattened. These organisms are parasites of animals. The type species is N. gonorrhoeae. [A. Neisser]
N. catarrhalis former name for Moraxella catarrhalis.
N. caviae a bacterial species found in the pharyngeal region of guinea pigs; may also be found in other animals.
N. flava a bacterial species found in the mucous membranes of the human respiratory tract; easily confused with N. meningitidis. SYN: N. subflava.
N. flavescens a bacterial species found in cerebrospinal fluid in cases of meningitis; probably occurs in the mucous membranes of the human respiratory tract.
N. gonorrhoeae a bacterial species that causes gonorrhea and other infections in humans; the type species of the genus N.. SYN: gonococcus, Neisser coccus.
N. haemolysans former name for Gemella haemolysans. See Gemella.
N. meningitidis a bacterial species found in the nasopharynx of humans but not in other animals; the causative agent of meningococcal meningitis and meningicoccemia; virulent organisms are strongly Gram negative and occur singly or in pairs; in the latter case the cocci are elongated and are arranged with long axes parallel and facing sides kidney shaped; groups characterized by serologically specific capsular polysaccharides are designated by capital letters (the main serogroups being A, B, C, and D). SYN: meningococcus, Weichselbaum coccus.
N. sicca a bacterial species found in the mucous membranes of the human respiratory tract.
N. subflava SYN: N. flava.

neisseria
neisseria, pl .neisseriae (ni-se′re-a, ni-se′re-e)

A vernacular term used to refer to any member of the genus N..

Nélaton
Nélaton

Auguste, French surgeon, 1807–1873. See N. catheter, N. fibers, under fiber, N. line, N. sphincter, Roser-N. line.

Nelson
Nelson

Don H., U.S. internist, *1925. See N. syndrome, N. tumor.

nem
nem

A nutritional unit defined as 1 gram breast milk of specific nutritional components having a caloric value equivalent to 23 calorie. [Ger. Nahrungseinheit Milch, milk nutrition unit]

nema- nema-, nemat-, nemato-

Thread, threadlike. [G. nema]

nemathelminth
nemathelminth (nem-a-thel′minth)

A member of the former phylum Nemathelminthes.

Nemathelminthes
Nemathelminthes (nem′a-thel-min′thez)

Formerly considered a phylum to incorporate the pseudocelomate organisms, which now are divided into the distinct phyla Acanthocephala, Entoprocta, Rotifera, Gastrotricha, Kinorhyncha, Nematoda, and Nematomorpha. [nemat- + G. helmins, helminthos, worm]

nematicidal
nematicidal, nematocidal (nem′a-ti-si′dal -to-si′ dal)

Destructive to nematode worms.

nematicide
nematicide, nematocide (ne-mat′i-sid -o-sid)

An agent that kills nematodes. [nematode + L. caedo, to kill]

nematization
nematization (nem′a-ti-za-shun)

Infestation by nematodes.

nematoblast
nematoblast (nem′ah-to-blast)

SYN: spermatid. [G., nema, thread + blastos, germ]

nematocyst
nematocyst (nem′a-to-sist)

A stinging cell of coelenterates consisting of a poison sac and a coiled barbed sting capable of being ejected and penetrating the skin of an animal on contact; of considerable consequence in large jellyfish and in the Portuguese man-of-war whose large numbers of these stinging cells can cause great pain and even death. SYN: cnida, cnidocyst. [nemato- + G. kystis, bladder]

Nematoda
Nematoda (nem-a-to′da)

The roundworms, a large phylum that includes many of the helminths parasitic in humans and a far greater number of plant-parasitic and free-living soil and aquatic nonparasitic species. For practical purposes, the parasitic nematodes may be placed in two groups, based on their adult habitat in the human body: 1) the intestinal roundworms ( e.g., the genera Ascaris, Trichuris, Ancylostoma, Necator, Strongyloides, Enterobius, and Trichinella); and 2) the filarial roundworms of the blood, lymphatic tissues, and viscera ( e.g., the genera Wuchereria, Mansonella, Loa, Onchocerca, and Dracunculus). [nemat- + G. eidos, form]

nematode
nematode (nem′a-tod)

A common name for any roundworm of the phylum Nematoda.

nematodiasis
nematodiasis (nem′a-to-di′a-sis)

Infection with nematode parasites.
cerebrospinal n. invasion of the central nervous system by wandering nematode larvae; e.g., Angiostrongylus cantonensis in rats and humans.

Nematodirella longispiculata
Nematodirella longispiculata (ne′ma-to-di-rel′a lon′gi-spik-u-la′ta)

One of the thread-necked trichostrongyle nematodes in the small intestine of sheep, goats, reindeer, moose, musk ox, and pronghorn.

nematoid
nematoid (nem′a-toyd)

Relating to nematodes.

nematologist
nematologist (nem-a-tol′o-jist)

A specialist in nematology.

nematology
nematology (nem-a-tol′o-je)

The science concerned with all aspects of nematodes, their biology, and their importance to humans. [nematode + G. logos, study]

nematospermia
nematospermia (nem′a-to-sper′me-a)

Spermatozoa with an elongated tail, as in humans, in contrast to spherospermia. [nemat- + G. sperma, seed]

Némethy
Némethy

George, Hungarian-U.S. biochemist, *1934. See Adair-Koshland-N.-Filmer model, Koshland-N.-Filmer model.

neo- neo-

New, recent. [G. neos]

neoadjuvant
neoadjuvant (ne-o-ad′joo-vant)

Chemotherapy or radiation given before cancer surgery. [neo- + adjuvant]

neoantigens
neoantigens (ne-o-an′ti-jenz)

SYN: tumor antigens, under antigen.

neoarsphenamine
neoarsphenamine (ne′o-ar-sfen′a-men)

Formerly used as an antisyphilitic agent.

neoarthrosis
neoarthrosis (ne-o-ar-thro′sis)

SYN: nearthrosis.

Neoascaris vitulorum
Neoascaris vitulorum (ne-o-as′ka-ris vit-u-lo′rum)

The large roundworm occurring in the small intestine of cattle, water buffalo, and (rarely) sheep; although uncommon in the U.S., it is a serious cattle parasite in many other areas. Experimental infection has been produced in rodents and humans.

neobiogenesis
neobiogenesis (ne′o-bi-o-jen′e-sis)

The theory that life can originate from nonliving matter. [neo- + G. bios, life, + genesis, origin]

neobladder
neobladder (ne′o-blad′er)

Surgically constricted (usually using stomach or intestine) replacement for urinary bladder.

neoblastic
neoblastic (ne-o-blas′tik)

Developing in or characteristic of new tissue. [neo- + G. blastos, germ, offspring]

neocerebellum
neocerebellum (ne′o-ser-e-bel′um) [TA]

Phylogenetic term referring to the larger lateral portion of the cerebellar hemisphere receiving its dominant input from the pontine nuclei which, in turn, are dominated by afferent nerves originating from all parts of the cerebral cortex; phylogenetically, of more recent origin than the archicerebellum and paleocerebellum, q.v., the n. reaches its largest development in humans and other primates. SYN: corticocerebellum.

neochymotrypsinogen
neochymotrypsinogen (ne-o-ki′mo-trip-sin′o-jen)

An intermediate in the conversion of chymotrypsin to α-chymotrypsin by chymotrypsin cleavage.

neocinchophen
neocinchophen (ne-o-sin′ko-fen)

The ethyl ester of 6-methyl-2-phenylquinolin-4-carboxylic acid; its action and uses are similar to those of cinchophen.

neocortex
neocortex (ne-o-kor′teks) [TA]

SYN: isocortex.

neocystostomy
neocystostomy (ne′o-sis-tos′to-me)

SYN: ureteroneocystostomy. [neo- + G. kystis, bladder, + stoma, mouth]

neodymium
neodymium (Nd) (ne-o-dim′e-um)

One of the rare earth elements; atomic no. 60, atomic wt. 144.24. [neo-, new, + G. didymos, twin (of lanthanum)]

neoencephalon
neoencephalon (ne-o-en-sef′a-lon)

SYN: neencephalon.

neofetal
neofetal (ne-o-fe′tal)

Relating to the neofetus or to the transition between the embryonic and fetal periods of development.

neofetus
neofetus (ne-o-fe′tus)

The intrauterine organism at about 8 weeks of development.

neoformation
neoformation (ne′o-for-ma′shun)

1. Formation of neoplasia, or a neoplasm. 2. Sometimes used to indicate the process of regeneration, or a regenerated tissue or part.

neogenesis
neogenesis (ne-o-jen′e-sis)

SYN: regeneration (1) . [neo- + G. genesis, origin]

neogenetic
neogenetic (ne′o-je-net′ik)

Pertaining to or characterized by neogenesis.

neokinetic
neokinetic (ne′o-ki-net′ik)

Denoting one of the divisions of the motor system, the function of which is the transmission of isolated synergic movements of voluntary origin; it represents a more highly specialized form of movement than the paleokinetic function. [neo- + G. kinetikos, relating to movement]

neolallism
neolallism (ne-o-lal′izm)

Abnormal use of neologisms in speech. [neo- + G. laleo, to chatter]

neologism
neologism (ne-ol′o-jizm)

A new word or phrase of the patient's own making often seen in schizophrenia ( e.g., headshoe to mean hat), or an existing word used in a new sense; in psychiatry, such usages may have meaning only to the patient or be indicative of the patient's condition. [neo- + G. logos, word]

neomorph
neomorph, neomorphism (ne′o-morf, ne′o-mor′fizm)

A new formation; a structure found in higher organisms, only slight or no traces of which exist in lower orders. [neo- + G. morphe, form]

neomycin sulfate
neomycin sulfate (ne-o-mi′sin)

The sulfate of an antibacterial antibiotic substance produced by the growth of Streptomyces fradiae, active against a variety of Gram-positive and Gram-negative bacteria.

neon
neon (Ne) (ne′on)

An inert gaseous element in the atmosphere, separated from argon by W. Ramsay and M. Travers in 1898; atomic no. 10, atomic wt. 20.1797. [G. neos, new]

neonatal
neonatal (ne-o-na′tal)

Relating to the period immediately succeeding birth and continuing through the first 28 days of extrauterine life. SYN: newborn. [neo- + L. natalis, relating to birth]

neonate
neonate (ne′o-nat)

An infant aged 1 month or less. SYN: newborn. [neo- + L. natus, born, fr. nascor, to be born]

neonatologist
neonatologist (ne′o-na-tol′o-jist)

One who specializes in neonatology.

neonatology
neonatology (ne′o-na-tol′o-je)

The pediatric subspecialty concerned with disorders of the neonate. SYN: neonatal medicine. [neo- + L. natus, pp. born, + G. logos, theory]

neoneurotization
neoneurotization (ne-o-noo-rot′i-za′shun)

Rarely observed phenomenon of return of facial motor function following deliberate transection of the facial nerve; believed to represent trigeminal reinnervation of the facial muscles.

neopallium
neopallium (ne-o-pal′e-um)

SYN: isocortex.

neophobia
neophobia (ne-o-fo′be-a)

Morbid aversion to, or dread of, novelty or the unknown. [neo- + G. phobos, fear]

neoplasia
neoplasia (ne-o-pla′ze-a)

The pathologic process that results in the formation and growth of a neoplasm. [neo- + G. plasis, a molding]
cervical intraepithelial n. dysplastic changes beginning at the squamocolumnar junction in the uterine cervix that may be precursors of squamous cell carcinoma: grade 1, mild dysplasia involving the lower one-third or less of the epithelial thickness; grade 2, moderate dysplasia with one-third to two-thirds involvement; grade 3, severe dysplasia or carcinoma in situ, with two-thirds to full-thickness involvement.
lobular n. SYN: noninfiltrating lobular carcinoma.
multiple endocrine n. (MEN) a group of disorders characterized by functioning tumors in more than one endocrine gland. SYN: familial multiple endocrine adenomatosis, multiple endocrine adenomatosis.
multiple endocrine n. 1 [MIM*131100] syndrome characterized by tumors of the pituitary gland, pancreatic islet cells, and parathyroid glands and may be associated with Zollinger-Ellison syndrome; autosomal dominant inheritance, caused by mutation in the MEN1 gene on chromosome 11q.
multiple endocrine n. 2 [MIM*171400] syndrome associated with pheochromocytoma, parathyroid adenoma and medullary thyroid carcinoma; autosomal dominant inheritance, caused by mutation in the RET oncogene on chromosome 10q.
multiple endocrine n. 3 [MIM*162300] syndrome characterized by tumors found in MEN2, tall, thin habitus, prominent lips, and neuromas of the tongue and eyelids; autosomal dominant inheritance, caused by mutation in the RET oncogene on 10q. SYN: multiple endocrine n. 2B.
multiple endocrine n. 2B SYN: multiple endocrine n. 3.
multiple endocrine n., type 1 SYN: multiple endocrine n. syndrome, type 1.
multiple endocrine n., type 2A (MEN2A) SYN: multiple endocrine n. syndrome, type 2A.
prostatic intraepithelial n. (PIN) dysplastic changes involving glands and ducts of the prostate that may be a precursor of adenocarcinoma; low grade (PIN 1), mild dysplasia with cell crowding, variation in nuclear size and shape, and irregular cell spacing; high grade (PIN 2 and 3), moderate to severe dysplasia with cell crowding, nucleomegaly and nucleolomegaly, and irregular cell spacing.
vaginal intraepithelial n. preinvasive squamous cell carcinoma (carcinoma in situ) limited to vaginal epithelium; like vulvar or cervical intraepithelial n., graded histologically on a scale from 1 to 3 or subdivided into low-grade and high-grade intraepithelial malignancy; usually related to human papilloma virus infection; may progress to invasive carcinoma.
vulvar intraepithelial n. preinvasive squamous cell carcinoma (carcinoma in situ) limited to vulvar epithelium; like vaginal or cervical intraepithelial n., graded histologically on a scale from 1 to 3 or subdivided into low-grade and high-grade intraepithelial malignancy; usually related to human papilloma virus infection; may progress to invasive carcinoma.

neoplasm
neoplasm (ne′o-plazm)

An abnormal tissue that grows by cellular proliferation more rapidly than normal and continues to grow after the stimuli that initiated the new growth cease. Neoplasms show partial or complete lack of structural organization and functional coordination with the normal tissue, and usually form a distinct mass of tissue that may be either benign (benign tumor) or malignant (cancer). SYN: new growth, tumor (2) . [neo- + G. plasma, thing formed]
histoid n. old term for a n. characterized by a cytohistologic pattern that closely resembles the tissue from which the neoplastic cells are derived.

neoplastic
neoplastic (ne-o-plas′tik)

Pertaining to or characterized by neoplasia, or containing a neoplasm.

neopterin
neopterin (ne-op′trin)

A pteridine present in body fluids; elevated levels result from immune system activation, malignant disease, allograft rejection, and viral infections (especially as in AIDS). [neo- + G. pteron, wing, + -in]

neopyrithiamin
neopyrithiamin (ne′o-pir-i-thi′a-min)

SYN: pyrithiamin.

neoretinal b
neoretinal b (ne-o-ret′in-al)

SYN: 11-cis-retinal.

neoretinene B
neoretinene B (ne-o-ret′i-nen)

SYN: 11-cis-retinol.

Neospora canium
Neospora canium (ne-o-spor-a kan′-e-um)

A protozoan parasite of dogs in the phylum Apicomplexa, an intracellular cyst-forming pathogen of neural and other tissues. Its epidemiology and life history are unknown.

neostigmine
neostigmine (ne-o-stig′min)

A synthetic compound, similar in action to physostigmine (eserine); a reversible cholinesterase inhibitor, used as the bromide or methylsulfate salts in the treatment of myasthenia gravis, postoperative distention, urinary retention, and antagonist of stabilizing neuromuscular blocking drugs.

neostomy
neostomy (ne-os′to-me)

Surgical construction of a new or artificial opening. [neo- + G. stoma, mouth]

neostriatum
neostriatum (ne-o-stri-a′tum)

striatum.

neoteny
neoteny (ne-ot′e-ne)

Prolongation of the larval state, as in the Mexican tiger salamander or axolotl, or in certain termite castes held in the larval stage as future replacements of the queen. Cf.:pedogenesis. [neo- + G. teino, to stretch]

Neotestudina rosati
Neotestudina rosati (ne′o-tes-too-di′na ro-sa′ti)

A species of fungus that causes white grain mycetoma in Somalia and elsewhere in Africa.

neothalamus
neothalamus (ne-o-thal′a-mus)

The portion of the thalamus projecting to the neocortex.

neotyrosine
neotyrosine (ne-o-ti′ro-sen)

Dimethyltyrosine;a tyrosine antimetabolite.

neovascularization
neovascularization (ne′o-vas′ku-lar-i-za′shun)

Proliferation of blood vessels in tissue not normally containing them, or proliferation of blood vessels of a different kind than usual in tissue.
choroidal n. ingrowth of new vessels from the choriocapillaris into the subretinal pigment epithelium and the retina; space associated with damage to the outer retina.
classic choroidal n. well-demarcated areas of hyperfluorescence observed in the early phases of a retinal angiogram.
occult choroidal n. area of leakage of undetermined source seen in the late phases of a retinal angiogram.
Type 1 choroidal n. ingrowth of new vessels from the choriocapillaris into the subretinal pigment epithelial space; associated with damage to the outer retina.
Type 2 choroidal n. ingrowth of new vessels from the choriocapillaris into the subretinal space; associated with damage to the outer retina.

neper
neper (Np)

A unit for comparing the magnitude of two powers, usually in electricity or acoustics; it is one half of the natural logarithm of the ratio of the two powers. SYN: napier. [fr. neperus, latinized form of (John) Napier]

nephelometer
nephelometer (nef-e-lom′e-ter)

An instrument used in nephelometry. [G. nephele, cloud, + metron, measure]

nephelometry
nephelometry (nef-e-lom′e-tre)

A technique for estimation of the number and size of particles in a suspension by measurement of light scattered from a beam of light passed through the solution.

nephr- nephr-

See nephro-.

nephralgia
nephralgia (ne-fral′je-a)

Rarely used term for pain in the kidney. [nephr- + G. algos, pain]

nephralgic
nephralgic (ne-fral′jik)

Relating to nephralgia.

nephrectomy
nephrectomy (ne-frek′to-me)

Removal of a kidney. [nephr- + G. ektome, excision]
abdominal n. transperitoneal removal of the kidney by an incision through the anterior abdominal wall.
laparoscopic n. removal of a kidney by percutaneous endoscopic technique.
lumbar n. extraperitoneal n. through a flank, loin, or posterior lumbar incision.
morcellated n. removal of a kidney in pieces.
posterior n. retroperitoneal removal of a kidney through an incision in the posterior lumbar muscles, usually with the patient in a prone position. SYN: lumbotomy incision.

nephredema
nephredema (nef-re-de′ma)

Edema caused by renal disease; rarely, edema of the kidney. [nephr- + G. oidema, swelling]

nephrelcosis
nephrelcosis (nef-rel-ko′sis)

Ulceration of the mucous membrane of the pelvis or calices of the kidney. [nephr- + G. helkosis, ulceration]

nephric
nephric (nef′rik)

Relating to the kidney. SYN: renal.

nephridium
nephridium, pl .nephridia (ne-frid′e-um, -a)

One of the paired, segmentally arranged excretory tubules of invertebrates such as the annelids. [G. nephros, kidney, + Mod. L. -idium, dim. suffix, fr. G. -idion]

nephritic
nephritic (ne-frit′ik)

Relating to or suffering from nephritis.

nephritis
nephritis, pl .nephritides (ne-fri′tis, -frit′i-dez)

Inflammation of the kidneys. [nephr- + G. -itis, inflammation]
acute n. SYN: acute glomerulonephritis.
acute interstitial n. interstitial n. with variable tubular damage and infiltration by numerous neutrophils, due to bacterial infection, urinary tract obstruction, or other causes (including drugs), which may be hypersensitivity reactions; accompanied by renal failure, fever, blood or tissue eosinophilia, and rash.
analgesic n. chronic interstitial n. with renal papillary necrosis, occurring in patients with a long history of excessive consumption of analgesics, especially those containing phenacetin. SYN: analgesic nephropathy.
anti–basement membrane n. glomerulonephritis produced by autologous or heterologous antibodies to the glomerular capillary basement membranes, the latter known as anti–kidney serum n..
anti–kidney serum n. experimental glomerulonephritis produced by injection of antiserum to kidney.
chronic n. SYN: chronic glomerulonephritis.
focal n. SYN: focal glomerulonephritis.
glomerular n. SYN: glomerulonephritis.
n. gravidarum n. developing in pregnancy.
hemorrhagic n. acute glomerulonephritis accompanied by hematuria.
hereditary n. [MIM*161900] familial renal disease occurring in adulthood characterized by proteinuria, hematuria, and hypertension progressing to chronic renal failure. There is no ocular defect or deafness; autosomal dominant inheritance. SEE ALSO: Alport syndrome.
immune complex n. an immune complex disease resulting from glomerular deposits, as in systemic lupus erythematosus.
interstitial n. a form of n. in which the interstitial connective tissue is chiefly affected.
lupus n. glomerulonephritis occurring in some patients with systemic lupus erythematosus, characterized by hematuria and a progressive course culminating in renal failure, often without hypertension; sometimes also applied to the nephrotic syndrome in patients with systemic lupus. Renal biopsies in patients with a progressive course show diffuse proliferative glomerulonephritis; in milder cases, there are focal proliferative glomerular lesions or mesangial n..
mesangial n. glomerulonephritis with an increase in glomerular mesangial cells or matrix, or mesangial deposits.
salt-losing n. a rare disorder resulting from renal tubular damage of a variety of etiologies; mimics adrenocortical insufficiency in that abnormal renal loss of sodium chloride occurs, accompanied by hyponatremia, azotemia, acidosis, dehydration, and vascular collapse. SYN: salt-losing syndrome, Thorn syndrome.
scarlatinal n. acute glomerulonephritis occurring as a complication of scarlet fever.
serum n. glomerulonephritis occurring in serum sickness or in animals injected with foreign serum protein.
subacute n. SYN: subacute glomerulonephritis.
suppurative n. focal glomerulonephritis with abscess formation in the kidney.
syphilitic n. a rare complication of congenital and secondary syphilis, with the nephrotic syndrome, resulting from glomerular immune-complex deposits.
transfusion n. renal failure and tubular damage resulting from the transfusion of incompatible blood; the hemoglobin of the hemolyzed red cells is deposited as casts in the renal tubules.
tuberculous n. n., mainly interstitial, due to the tubercle bacillus.
tubulointerstitial n. n. affecting renal tubules and interstitial tissue, with infiltration by plasma cells and mononuclear cells; seen in lupus n., allograft rejection, and methicillin sensitization.
uranium n. an experimental n. produced by the administration of uranium nitrate.

nephritogenic
nephritogenic (nef′ri-to-jen′ik)

Causing nephritis; said of conditions or agents. [nephritis + G. genesis, production]

nephro- nephro-, nephr-

The kidney. SEE ALSO: reno-. [G. nephros, kidney]

nephroblastema
nephroblastema (nef′ro-blas-te′ma)

SYN: nephric blastema. [nephro- + G. blastema, a sprout]

nephroblastoma
nephroblastoma (nef′ro-blas-to′ma)

SYN: Wilms tumor.

nephrocalcinosis
nephrocalcinosis (nef′ro-kal-si-no′sis)

A form of renal lithiasis characterized by diffusely scattered foci of calcification in the renal parenchyma; deposits of calcium phosphate, calcium oxalate monohydrate, and similar compounds are usually demonstrable radiologically. [nephro- + calcinosis]

nephrocapsectomy
nephrocapsectomy (nef′ro-kap-sek′to-me)

Obsolete operation for decortication, or decapsulation, of the kidney. [nephro- + L. capsula, a small box, + G. ektome, excision]

nephrocardiac
nephrocardiac (nef′ro-kar′de-ak)

SYN: cardiorenal. [nephro- + G. kardia, heart]

nephrocele
nephrocele (nef′ro-sel)

1. Hernial displacement of a kidney. [nephro- + G. kele, hernia] 2. Cavity of the nephrotome. SYN: nephrotomic cavity. [nephro- + G. koiloma, a hollow (celom)]

nephrocystosis
nephrocystosis (nef′ro-sis-to′sis)

Formation of renal cysts. [nephro- + G. kystis, cyst, + -osis, condition]

nephrogenetic
nephrogenetic, nephrogenic (nef′ro-je-net′ik, -jen′ik)

Developing into kidney tissue. [nephro- + G. genesis, origin]

nephrogenous
nephrogenous (ne-froj′e-nus)

Developing from kidney tissue.

nephrogram
nephrogram (nef′ro-gram)

1. Radiographic examination of the kidney after the intravenous injection of a water-soluble iodinated contrast material. 2. The diffuse opacification of the renal parenchyma following such injection, an indication of renal blood flow and glomerular filtration. A persistent n. indicates obstruction of kidney drainage.

nephrography
nephrography (ne-frog′ra-fe)

Radiography of the kidney. [nephro- + G. grapho, to write]

nephroid
nephroid (nef′royd)

Kidney-shaped; resembling a kidney. SYN: reniform. [nephro- + G. eidos, resemblance]

nephrolith
nephrolith (nef′ro-lith)

SYN: renal calculus. [nephro- + G. lithos, stone]

nephrolithiasis
nephrolithiasis (nef′ro-li-thi′a-sis)

Presence of renal calculi.

nephrolithotomy
nephrolithotomy (nef′ro-li-thot′o-me)

Incision into the kidney for the removal of a renal calculus. [nephro- + G. lithos, stone, + tome, incision]

nephrology
nephrology (ne-frol′o-je)

The branch of medical science concerned with medical diseases of the kidneys. [nephro- + G. logos, study]

nephrolysin
nephrolysin (ne-frol′i-sin)

An antibody that causes destruction of the cells of the kidneys, formed in response to the injection of an emulsion of renal substance; it is specific for the species from which the antigen was prepared.

nephrolysis
nephrolysis (ne-frol′i-sis)

1. Freeing of the kidney from inflammatory adhesions, with preservation of the capsule. 2. Destruction of renal cells. [nephro- + G. lysis, dissolution]

nephrolytic
nephrolytic (nef-ro-lit′ik)

Pertaining to, characterized by, or causing nephrolysis. SYN: nephrotoxic (2) .

nephroma
nephroma (ne-fro′ma)

A tumor arising from renal tissue. [nephro- + G. -oma, tumor]
mesoblastic n. a spindle cell neoplasm of the infant and, rarely, adult kidney with entrapped renal tubules.

nephromalacia
nephromalacia (nef′ro-ma-la′she-a)

Softening of the kidneys. [nephro- + G. malakia, softness]

nephromegaly
nephromegaly (nef-ro-meg′a-le)

Extreme hypertrophy of one or both kidneys. [nephro- + G. megas, great]

nephromere
nephromere (nef′ro-mer)

That portion of the intermediate mesoderm from which segmented kidney tubules develop. See nephrotome. [nephro- + G. meros, a part]

nephron
nephron (nef′ron)

A long convoluted tubular structure in the kidney, consisting of the renal corpuscle, the proximal convoluted tubule, the nephronic loop, and the distal convoluted tubule. SEE ALSO: uriniferous tubule. [G. nephros, kidney]

nephropathia
nephropathia (nef′ro-path′e-a)

SYN: nephropathy.
n. epidemica a generally benign form of epidemic hemorrhagic fever reported in Scandinavia.

nephropathic
nephropathic (nef′ro-path′ik)

Causing organic renal disease or impairment of renal function.

nephropathy
nephropathy (ne-frop′a-the)

Any disease of the kidney. SYN: nephropathia, nephrosis (1) . [nephro- + G. pathos, suffering]
analgesic n. SYN: analgesic nephritis.
Balkan n. interstitial chronic nephritis of unknown etiology, originally described as a disease endemic in the Balkans, characterized by insidious onset, scanty urinary findings, anemia, and acidosis. SYN: Danubian endemic familial n..
Danubian endemic familial n. SYN: Balkan n..
diabetic n. a syndrome occurring in people with diabetes mellitus and characterized by albuminuria, hypertension, and progressive renal insufficiency.Diabetic n. is a major cause of morbidity and mortality in people with diabetes mellitus (DM). People with diabetes make up the largest number (>25%) of those who start renal dialysis for end-stage renal disease (ESRD) each year in the U.S. The incidence of ESRD approaches 40% in people who have had type 1 DM for 20 years. The risk of diabetic n. is higher in males, blacks, Hispanics, and Native Americans. Within 3 years after the diagnosis of DM is made, histologic study shows thickening of glomerular basement membrane and mesangial expansion, changes characteristic of diabetic glomerulosclerosis (Kimmelstiel-Wilson disease). The kidneys increase in size and weight because of both hypertrophy and hyperplasia of parenchymal cells, and renal blood flow and glomerular filtration rate (GFR) are increased; as a result, serum creatinine and urea nitrogen are slightly reduced. After 10–15 years, the first evidence of renal damage may appear as microalbuminuria, a persistent excretion of albumin in concentrations not detected by routine tests for urinary protein. An albumin excretion rate of 20–200 μg/min (30–300 mg/day) heralds the onset of diabetic n. and strongly predicts eventual ESRD. Further progression of renal damage leads to frank albuminuria and a decline in glomerular filtration rate and nitrogen clearance. The prevalence of hypertension is markedly greater in persons with microalbuminuria, and hypertension accelerates the progression of renal disease. Diabetic n. can lead to hyperkalemia, metabolic acidosis, nephrotic syndrome, papillary necrosis, and increased susceptibility to acute renal failure after exposure to radiographic contrast media. Current practice guidelines for the treatment of DM call for annual assessment of 24-hour albumin excretion, prompt treatment of urinary tract infections, and avoidance of nephrotoxic drugs and radiographic dyes. No interventions have been shown to reverse clinical diabetic n.. However, prospective randomized studies have established that improved metabolic control, maintaining plasma glucose as near normal as possible at all times, can markedly decrease the development and progression of diabetic n., as well as of other long-term microvascular complications of diabetes (retinopathy and neuropathy). In addition, aggressive management of hypertension with ACE inhibitors or angiotensin II receptor blockers has been shown to delay progression of n. by mechanisms independent of blood pressure control, and limitation of daily protein intake to 0.8 g/kg of body weight (not appropriate in pregnancy) has been shown to delay progression of both diabetic and nondiabetic renal disease. ESRD is treated with kidney transplantation, hemodialysis, or peritoneal dialysis. Because diabetic retinopathy and neuropathy progress more rapidly with the onset of renal failure, dialysis is usually instituted early (when serum creatinine reaches about 6 mg/dL) in diabetic n..
hypokalemic n. vacuolation of the epithelial cytoplasm of renal convoluted tubules in patients seriously depleted of potassium; vacuoles do not contain fat or glycogen, concentrating ability is impaired, polyuria and polydipsia are common, and pyelonephritis may develop. SYN: vacuolar nephrosis.
IgA n. SYN: focal glomerulonephritis.
IgM n. SYN: mesangial proliferative glomerulonephritis.
reflux n. damaged renal parenchyma secondary to vesicoureteral reflux of infected urine.

nephropexy
nephropexy (nef′ro-pek-se)

Operative fixation of a floating or mobile kidney. SEE ALSO: nephrorrhaphy. [nephro- + G. pexis, fixation]

nephrophthisis
nephrophthisis (nef-rof′thi-sis, -ti-sis)

1. Suppurative nephritis with wasting of the substance of the organ. 2. Tuberculosis of the kidney. [nephro- + G. phthisis, a wasting]
familial juvenile n. cystic disease of renal medulla characterized by polyuria, polydipsia, anemia, and renal failure. There are two forms: one is inherited as an autosomal recessive [MIM*256100], caused by mutation in the NPHP1 gene on 2q13; the other is an autosomal dominant form [MIM*174000].

nephroptosis
nephroptosis, nephroptosia (nef-rop-to′sis, -to′se-a)

Prolapse of the kidney. [nephro- + G. ptosis, a falling]

nephropyosis
nephropyosis (nef′ro-pi-o′sis)

SYN: pyonephrosis. [nephro- + G. pyosis, suppuration]

nephrorrhaphy
nephrorrhaphy (nef-ror′a-fe)

Nephropexy by suturing the kidney. [nephro- + G. rhaphe, a suture]

nephros
nephros (nef′ros)

SYN: kidney.

nephrosclerosis
nephrosclerosis (nef′ro-skle-ro′sis)

Fibrosis of the kidney from overgrowth and contraction of the interstitial connective tissue. [nephro- + G. sklerosis, hardening]
arterial n. patchy atrophic scarring of the kidney due to arteriosclerotic narrowing of the lumens of large branches of the renal artery, occurring in old or hypertensive persons and occasionally causing hypertension. SYN: arterionephrosclerosis, senile n..
arteriolar n. renal scarring due to arteriolar sclerosis resulting from longstanding hypertension; the kidneys are finely granular and mildly or moderately contracted, with hyaline thickening of the walls of afferent glomerular arterioles and hyaline scarring of scattered glomeruli; chronic renal failure develops infrequently. SYN: arteriolonephrosclerosis, benign n..
benign n. SYN: arteriolar n..
malignant n. the renal changes in malignant hypertension; subcapsular petechiae, necrosis in the walls of scattered afferent glomerular arterioles, and red blood cells and casts in the urine, with uremia as a common termination.
senile n. SYN: arterial n..

nephrosclerotic
nephrosclerotic (nef′ro-skle-rot′ik)

Pertaining to or causing nephrosclerosis.

nephroscope
nephroscope (ne-fro′skop)

An endoscope passed into the renal pelvis to view it. Route of access may be percutaneous, through a surgically exposed kidney, or retrograde via the ureter.

nephrosis
nephrosis (ne-fro′sis)

1. SYN: nephropathy. 2. Degeneration of renal tubular epithelium. 3. SYN: nephrotic syndrome. [nephro- + G. -osis, condition]
acute n. acute oliguric renal failure, especially that caused by certain poisons.
acute lobar n. a severe but localized bacterial infection of the renal parenchyma that may produce a mass effect simulating a renal abscess.
amyloid n. 1. SYN: renal amyloidosis. 2. the nephrotic syndrome due to deposition of amyloid in the kidney.
familial n. [MIM*256300] the nephrotic syndrome appearing in siblings in infancy, without nerve deafness; inherited as an autosomal recessive, the Finnish type of which is due to mutation in the nephrin gene on chromosome 19q.
hemoglobinuric n. acute oliguric renal failure associated with hemoglobinuria, due to massive intravascular hemolysis, e.g., following an incompatible blood transfusion; the kidneys show the morphologic changes of hypoxic n..
hypoxic n. acute oliguric renal failure following hemorrhage, burns, shock, or other causes of hypovolemia and reduced renal blood flow; frequently associated with patchy tubular necrosis, tubulorrhexis, and distal tubular casts of hemoglobin.
lipoid n. idiopathic nephrotic syndrome occurring most commonly in children, in which glomeruli show minimal changes with no thickening of the basement membranes, fat vacuoles in the tubular epithelium, and fusion of glomerular foot processes. SYN: minimal-change disease, nil disease.
osmotic n. swelling of renal tubular epithelium associated with glomerular filtration of sugars and dextrose; the swelling is due to formation of cytoplasmic vesicles by pinocytosis, and is reversible, probably with no dysfunction, when produced by glucose or mannitol.
toxic n. acute oliguric renal failure due to chemical poisons, septicemia, or bacterial toxemia; frequently associated with extensive necrosis of proximal convoluted tubules.
vacuolar n. SYN: hypokalemic nephropathy.

nephrostogram
nephrostogram (ne-fros′to-gram)

A radiograph of the kidney after opacification of the renal pelvis by injecting a contrast agent through a nephrostomy tube. [nephrostomy + G. gramma, writing]

nephrostoma
nephrostoma, nephrostome (ne-fros′to-ma, nef′ro-stom)

One of the ciliated funnel-shaped openings by which pronephric and some primitive mesonephric tubules communicate with the celom. [nephro- + G. stoma, mouth]

nephrostomy
nephrostomy (ne-fros′to-me)

Establishment of an opening between the collecting system of the kidney through its parenchyma to the exterior of the body; may be performed by surgical incision or be placed percutaneously. [nephro- + G. stoma, mouth]
percutaneous n. drainage of the collecting system through a catheter inserted through the skin of the flank under fluoroscopic control, usually using the Seldinger technique.

nephrotic
nephrotic (nef-rot′ik)

Relating to, caused by, or similar to nephrosis.

nephrotome
nephrotome (nef′ro-tom)

The segmented intermediate mesoderm develops into nephric primordia. [nephro- + G. tome, a cutting]

nephrotomic
nephrotomic (nef-ro-tom′ik)

Relating to the nephrotome.

nephrotomogram
nephrotomogram (nef-ro-to′mo-gram)

A tomographic examination of the kidneys following the intravenous administration of contrast material for the purpose of improving demonstration of renal parenchymal abnormalities. [nephro- + G. tomos, a cutting + gramma, a writing]

nephrotomography
nephrotomography (nef′ro-to-mog′ra-fe)

Tomographic examination of the kidney.

nephrotomy
nephrotomy (ne-frot′o-me)

Incision into the kidney. [nephro- + G. tome, incision]
anatrophic n. an incision into the posterolateral renal parenchyma, gaining access to the calyceal system through an avascular plane between anterior and posterior branches of the renal artery; used for removal of calyceal and branched renal calculi, with maximum exposure yet minimal bleeding or parenchymal damage. SYN: Smith-Boyce operation.

nephrotoxic
nephrotoxic (nef-ro-tok′sik)

1. Pertaining to nephrotoxin; toxic to renal cells. 2. SYN: nephrolytic.

nephrotoxicity
nephrotoxicity (nef′ro-tok-sis′i-te)

The quality or state of being toxic to kidney cells.

nephrotoxin
nephrotoxin (nef-ro-tok′sin)

A cytotoxin that is specific for cells of the kidney.

nephrotrophic
nephrotrophic (nef-ro-trof′ik)

SYN: renotrophic.

nephrotropic
nephrotropic (nef-ro-trop′ik)

SYN: renotrophic.

nephrotuberculosis
nephrotuberculosis (nef′ro-too-ber-ku-lo′sis)

Tuberculosis of the kidney.

nephroureterectasis
nephroureterectasis (nef′ro-u-re′ter-dk-ta′sis)

SYN: ureterohydronephrosis.

nephroureterectomy
nephroureterectomy (nef′ro-u-re′ter-ek′to-me)

Surgical removal of a kidney and its ureter. SYN: ureteronephrectomy. [nephro- + ureter + G. ektome, excision]

nephroureterocystectomy
nephroureterocystectomy (nef′ro-u-re′ter-o-sis-tek′to-me)

Removal of kidney, ureter, and part or all of the bladder. [nephro- + ureter + G. kystis, bladder, + ektome, excision]

neptunium
neptunium (Np) (nep-too′ne-um)

A radioactive element; atomic no. 93; first element of the transuranian series (not found in nature); ²³⁷Np has a half-life of 2.14 × 10⁶ years. [planet, Neptune]

neral
neral (ne′ral)

cis-Citral. See citral.

Néri
Néri

Vincenzo, Italian neurologist, *1882. See N. sign.

neriine
neriine (ne′ri-en)

SYN: conessine.

Nernst
Nernst

Walther, German physicist and Nobel laureate, 1864–1941. See N. equation.

nerve
nerve (nerv) [TA]

A whitish cordlike structure composed of one or more bundles (fascicles) of myelinated or unmyelinated n. fibers, or more often mixtures of both, coursing outside the central nervous system, together with connective tissue within the fascicle and around the neurolemma of individual n. fibers (endoneurium), around each fascicle (perineurium), and around the entire n. and its nourishing blood vessels (epineurium), by which stimuli are transmitted from the central nervous system to a part of the body or the reverse. N. branches are given in the definition of the major n.; many are also listed and defined under branch. SYN: nervus [TA] . [L. nervus]
abdominopelvic splanchnic nerves visceral branches of the sympathetic trunks conveying presynaptic sympathetic fibers to and visceral afferent fibers from the prevertebral ganglia and para-aortic/hypogastric plexuses for the innervation of viscera located below the diaphragm. The greater, lesser, lowest, lumbar, and sacral splanchnic nerves belong to this group.
abducens n. abducent n. [CN VI].
abducent n. [CN VI] [TA] a small motor n. supplying the lateral rectus muscle of the eye; its origin is in the dorsal part of the tegmentum of the pons just below the surface of the rhomboid fossa, and it emerges from the brain in the fissure between the medulla oblongata and the posterior border of the pons (medullopontine sulcus); it enters the dura of the clivus and passes through the cavernous sinus, entering the orbit through the superior orbital fissure. SYN: nervus abducens [CN VI] [TA] , abducens n.&star, abducent (2) , sixth cranial n. [CN VI].
accelerator nerves certain of the cardiopulmonary splanchnic nerves establishing the sympathetic innervation of the heart; originating from ganglion cells of the superior, middle, and inferior cervical ganglion of the sympathetic trunk, the unmyelinated efferent fibers of the accelerator nerves stimulate an increase in the heart rate.
accessory n. [CN XI] [TA] arises by two sets of roots: the presumed cranial, emerging from the side of the medulla, and spinal, emerging from the ventrolateral part of the first five cervical segments of the spinal cord; these roots unite to form the accessory n. trunk, which divides into two branches, internal and external; the internal branch, carrying fibers of the cranial root, unites with the vagus in the jugular foramen and supplies the muscles of the pharynx, larynx, and soft palate; the external branch continues independently through the jugular foramen to supply the sternocleidomastoid and trapezius muscles. While the accessory n. was originally believed to have cranial and spinal roots, it is now the general view that the so-called cranial root is actually a portion of the vagus n.. SYN: nervus accessorius [CN XI] [TA] , accessorius willisii, eleventh cranial n. [CN XI], spinal accessory n..
accessory phrenic nerves [TA] accessory n. strands that arise from the fifth cervical n., often as branches of the n. to the subclavius, passing downward to join the phrenic n.. SYN: nervi phrenici accessorii [TA] .
acoustic n. an archaic term sometimes used to designate the vestibulocochlear n. [CN VIII].
afferent n. a n. conveying impulses from the periphery to the central nervous system. SYN: centripetal n., esodic n..
Andersch n. SYN: tympanic n..
anococcygeal n. small n. arising from the coccygeal plexus, supplying the skin over the coccyx. SYN: nervus anococcygeus.
anterior ampullary n. [TA] a branch of the utriculoampullar n. that supplies the crista ampullaris of the anterior semicircular duct. SYN: nervus ampullaris anterior [TA] .
anterior antebrachial n. SYN: anterior interosseous n..
anterior auricular nerves [TA] branches of the auriculotemporal n. that supply the tragus and upper part of the auricle. SYN: nervi auriculares anteriores [TA] .
anterior crural n. SYN: femoral n..
anterior cutaneous nerves of abdomen SYN: thoracoabdominal nerves.
anterior ethmoidal n. [TA] a branch of the nasociliary n.; passes through anterior ethmoidal foramen on superomedial wall of orbit into cranial cavity, giving rise to anterior meningeal nerves, then passes through cribriform plates into nasal cavity, supplying anterosuperior nasal mucosa. SYN: nervus ethmoidalis anterior [TA] .
anterior femoral cutaneous nerves SYN: anterior cutaneous branches of femoral n., under branch.
anterior interosseous n. [TA] a branch of the median arising in the elbow region, running on interosseous membrane, supplying the flexor pollicis longus, part of flexor digitorum profundus and the pronator quadratus muscles, as well as radiocarpal and intercarpal joints. SYN: nervus interosseus antebrachii anterior [TA] , anterior antebrachial n., nervus antebrachii anterior, volar interosseous n..
anterior labial nerves [TA] branches of the ilioinguinal n. distributed to the labia majora, mons pubis, and adjacent thigh. SYN: nervi labiales anteriores [TA] .
anterior scrotal nerves [TA] the branches of the ilioinguinal n., distributed to the skin of the root of the penis, mons pubis, adjacent thigh, and anterior surface of the scrotum. SYN: nervi scrotales anteriores [TA] .
anterior superior alveolar nerves [TA] the branches of the superior alveolar n. that supply the incisors, canines, premolars, and first molar by their contributions to the superior dental plexus. SYN: anterior superior alveolar branches of infraorbital n., rami alveolares superiores anteriores nervi infraorbitalis.
anterior supraclavicular n. SYN: medial supraclavicular n..
anterior tibial n. SYN: deep fibular n..
aortic n. a branch of the vagus that ends in the aortic arch and base of the heart; composed entirely of afferent fibers; its stimulation elicits a brainstem reflex that causes slowing of the heart, dilation of the peripheral vessels, and a fall in blood pressure. SYN: Cyon n., depressor n. of Ludwig, Ludwig n..
Arnold n. SYN: auricular branch of vagus n..
articular n. a branch of a n. supplying a joint. SYN: nervus articularis.
auditory n. SYN: cochlear n..
augmentor nerves SYN: cervical splanchnic nerves.
auriculotemporal n. [TA] a branch of the mandibular, usually arising by two roots embracing the middle meningeal artery; it passes through the parotid gland conveying postsynaptic parasympathetic secretomotor fibers from the otic ganglion, and continuing to terminate in the skin of the temple and scalp; also sends branches to the external acoustic meatus, tympanic membrane, and auricle as well as a communicating branch to the facial n.. SYN: nervus auriculotemporalis [TA] .
autonomic n. a bundle of autonomic n. fibers outside of the central nervous system belonging or relating to the autonomic (visceral motor) nervous system. SYN: nervus autonomicus [TA] .
axillary n. [TA] arises from the posterior cord of the brachial plexus in the axilla, passes laterally and posteriorly through quadrangular space with the posterior circumflex humeral artery, winding round the surgical neck of the humerus to supply the deltoid and teres minor muscles, terminating as the superior lateral brachial cutaneous n.. SYN: nervus axillaris [TA] , circumflex n..
baroreceptor n. SYN: pressoreceptor n..
Bell respiratory n. SYN: long thoracic n..
Bock n. SYN: pharyngeal n..
buccal n. [TA] a sensory branch of the mandibular division of the trigeminal n.; it passes downward, emerging from beneath the ramus of the mandible to run forward on the buccinator muscle, piercing (but not supplying) it to supply the buccal mucous membrane and skin of the cheek near the angle of the mouth. SYN: nervus buccalis [TA] , buccinator n., long buccal n..
buccinator n. SYN: buccal n..
cardiopulmonary splanchnic nerves visceral branches of the sympathetic trunks conveying postsynaptic sympathetic fibers to and visceral afferent fibers from viscera located above the diaphragm, mainly via the cardiac, pulmonary, and esophageal plexuses. The cervical and upper thoracic splanchnic nerves are part of this group.
caroticotympanic nerves two sympathetic branches from the internal carotid plexus to the tympanic plexus. SYN: nervi caroticotympanicus, small deep petrosal n..
carotid sinus n. SYN: carotid branch of glossopharyngeal n. (CN IX).
n. to carotid sinus SYN: carotid branch of glossopharyngeal n. (CN IX).
cavernous nerves of clitoris [TA] nerves corresponding to the cavernous nerves of penis in the male, arising from the vesicular portion of the pelvic plexus. SYN: nervi cavernosi clitoridis [TA] , cavernous plexus of clitoris.
cavernous nerves of penis [TA] two nerves, major and minor, derived from the prostatic portion of the pelvic plexus supplying sympathetic and parasympathetic fibers to the helicine arteries and arteriorvenous anastomoses of the corpus cavernosum stimulating erection. SYN: nervi cavernosi penis [TA] , cavernous plexus of penis.
centrifugal n. SYN: efferent n..
centripetal n. SYN: afferent n..
cervical nerves [C1–C8] spinal nerves arising from the cervical segments of the spinal cord. SYN: nervi cervicales [C1–C8].
cervical splanchnic nerves visceral branches arising from the superior, middle, and inferior (stellate) cervical ganglia; they include the superior, middle, and inferior cervical cardiac nerves and are part of the cardiopulmonary splanchnic nerves. SYN: augmentor nerves.
circumflex n. SYN: axillary n..
coccygeal n. [Co] [TA] a small n., the lowest of the spinal nerves, entering into the formation of the coccygeal plexus. SYN: nervus coccygeus [Co] [TA] .
cochlear n. [TA] the part of the vestibulocochlear n. [CN VIII] peripheral to the cochlear root; composed of the central n. processes of the bipolar neurons of the spiral ganglion, which have their peripheral processes on the four rows of neuroepithelial cells (hair cells) of the spiral organ. SEE ALSO: cochlear root of VIII n.. SYN: nervus cochlearis [TA] , auditory n., cochlear part of vestibulocochlear n., inferior part of vestibulocochlear n., pars cochlearis nervi vestibulocochlearis.
common fibular n. [TA] one of the terminal divisions of the sciatic n., diverging from the tibial n. at the upper end of the popliteal fossa, then coursing with the biceps tendon along the lateral portion of the popliteal space to wind around the neck of the fibula where it divides into the superficial and deep peroneal nerves. The common peroneal n., or its deep branch, is the most commonly injured n., being located in a lateral subcutaneous position at the fibular neck; a lesion causes a loss of ability to dorsiflex the foot (&dquor;foot drop&dquor;). SYN: nervus fibularis communis [TA] , common peroneal n.&star, nervus peroneus communis&star.
common palmar digital nerves [TA] four nerves in the palm that send branches (proper palmar digital nerves) to adjacent sides of two digits; three are branches of the median n., one is from the ulnar n.. SYN: nervi digitales palmares communes [TA] .
common peroneal n. common fibular n..
common plantar digital nerves [TA] three nerves derived from the medial plantar n. and one from the lateral plantar n. that supply the skin overlying the metatarsals and terminate as proper plantar digital nerves to the side of each toe. SYN: nervi digitales plantares communes [TA] .
cranial nerves [TA] those nerves that emerge from, or enter, the cranium or skull, in contrast to the spinal nerves, which emerge from the spine or vertebral column. The twelve paired cranial nerves are the olfactory [CN I], optic [CN II], oculomotor [CN III], trochlear [CN IV], trigeminal [CN V], abducent [CN VI], facial [CN VII], vestibulocochlear [CN VIII], glossopharyngeal [CN IX], vagal [CN X], accessory [CN XI], and hypoglossal [CN XII] nerves. SYN: nervi craniales [TA] .
crural interosseous n. [TA] a n. given off from one of the muscular branches of the tibial n. which passes down over the posterior surface of the interosseous membrane supplying it and the two bones of the leg. SYN: nervus interosseus cruris [TA] , interosseous n. of leg.
cubital n. SYN: ulnar n..
cutaneous n. [TA] a mixed n. supplying a region of the skin, including its sensory endings, blood vessels, smooth muscle and glands. SYN: nervus cutaneus [TA] .
cutaneous cervical n. SYN: transverse cervical n..
Cyon n. SYN: aortic n..
dead n. misnomer for nonvital dental pulp.
deep fibular n. [TA] one of the terminal branches of the common peroneal n., arising at the fibular neck and passing into the anterior compartment of the leg; it supplies the tibialis anterior, extensor hallucis longus, extensor digitorum longus, and peroneus tertius muscles in the leg, then crosses the ankle joint to supply the muscles on the dorsum of the foot (extensors hallucis and digitorum brevis), becoming cutaneous to innervate adjacent sides of the great and second toes. SYN: nervus fibularis profundus [TA] , deep peroneal n.&star, nervus peroneus profundus&star, anterior tibial n..
deep peroneal n. deep fibular n..
deep petrosal n. [TA] the deep petrosal branch of the internal carotid plexus, which joins the greater petrosal n. at the entrance of the pterygoid canal forming the n. of the pterygoid canal and thus provides postsynaptic fibers to the pterygopalatine ganglion. SYN: nervus petrosus profundus [TA] , radix sympathica ganglii pterygopalatini&star, sympathetic root of pterygopalatine ganglion&star.
deep temporal nerves [TA] two branches, anterior and posterior, from the mandibular n., supplying the temporalis muscle and periosteum of the temporal fossa. SYN: nervi temporales profundi [TA] .
dental n. 1. layperson's term for a dental pulp; 2. branches of the inferior and superior alveolar nerves to the teeth. See inferior alveolar n., superior alveolar nerves.
depressor n. of Ludwig SYN: aortic n..
dorsal n. of clitoris [TA] the deep terminal branch of the pudendal, supplying especially the glans clitoridis after passing through the deep perineal musculature, to run along the dorsum of the clitoral shaft. SYN: nervus dorsalis clitoridis [TA] .
dorsal digital nerves SYN: dorsal digital nerves of hand.
dorsal digital nerves of deep fibular n. [TA] terminal sensory portion of the deep fibular (peroneal) n. on the dorsum of the foot, remaining after the motor branches to the extensor digitorum brevis and extensor hallucis brevis muscles have been supplied; provides cutaneous innervation to a small, wedge-shaped area that includes the adjacent sides of the great and second toes. SYN: nervi digitales dorsales nervi fibularis profundi [TA] .
dorsal digital nerves of foot [TA] nerves supplying the skin of the dorsal aspect of the proximal and middle phalanges of the toes. See dorsal digital nerves of superficial fibular n., dorsal digital nerves of deep fibular n.. SYN: nervi digitales dorsales pedis [TA] , dorsal nerves of toes.
dorsal digital nerves of hand [TA] terminal branches of the radial and ulnar nerves in the hand supplying the skin of the dorsal surface of the proximal and middle phalanges of the fingers. See dorsal digital nerves of ulnar n.. SYN: dorsal digital nerves, nervi digitales dorsales.
dorsal digital nerves of superficial fibular n. [TA] nerves arising in the lateal fibular/peroneal) compartment of the leg that pass to the dorsum of the foot, supplying the skin of most of the dorsum of the foot and dorsal aspect of the toes, with the exception of a small wedge-shaped area including the adjacent sides of the great and second toes. SYN: nervi digitales dorsales nervi fibularis superficialis [TA] .
dorsal digital nerves of ulnar n. [TA] nerves arising from the dorsal branch of the ulnar n. supplying the skin of the dorsal aspect of the little and ulnar half of the ring fingers and adjacent area of the dorsum of the hand. SYN: nervi digitales dorsales nervi ulnaris [TA] .
dorsal interosseous n. SYN: posterior interosseous n..
dorsal lateral cutaneous n. SYN: lateral dorsal cutaneous n..
dorsal medial cutaneous n. SYN: medial dorsal cutaneous n..
dorsal n. of penis [TA] the deep terminal branch of the pudendal nerves that runs through the deep perineal muscles giving branches, then runs along the dorsum of the penis, supplying the skin of the penis, the prepuce, the corpora cavernosa, and the glans. SYN: nervus dorsalis penis [TA] .
dorsal n. of scapula SYN: dorsal scapular n..
dorsal scapular n. [TA] arises from ventral primary rami of the fifth to seventh cervical nerves and passes downward to supply the levator scapulae and the rhomboideus major and minor muscles. SYN: nervus dorsalis scapulae [TA] , dorsal n. of scapula, n. to rhomboid, posterior scapular n..
dorsal nerves of toes SYN: dorsal digital nerves of foot.
efferent n. a n. conveying impulses from the central nervous system to the periphery. SYN: centrifugal n., exodic n..
eighth n. SYN: vestibulocochlear n. [CN VIII].
eighth cranial n. [CN VIII] SYN: vestibulocochlear n. [CN VIII].
eleventh cranial n. [CN XI] SYN: accessory n. [CN XI].
esodic n. SYN: afferent n..
excitor n. a n. conducting impulses that stimulate to increase function.
excitoreflex n. a visceral n. the special function of which is to cause reflex action.
exodic n. SYN: efferent n..
n. to external acoustic meatus [TA] a branch of the auriculotemporal n. supplying the lining of the external acoustic meatus. SYN: nervus meatus acustici externi [TA] .
external carotid nerves [TA] cephalic arterial ramus of the sympathetic trunk, conveying a number of sympathetic n. fibers extending from the superior cervical ganglion to the external carotid artery to form the external carotid plexus. SYN: nervi carotici externi [TA] .
external respiratory n. of Bell SYN: long thoracic n..
external saphenous n. SYN: sural n..
external spermatic n. SYN: genital branch of genitofemoral n..
facial n. [CN VII] [TA] n. with origin in the tegmentum of the lower portion of the pons; it emerges from the brain at the posterior border of the pons; it leaves the cranial cavity through the internal acoustic meatus where it is joined by the intermediate n., traverses the facial canal in the petrous portion of the temporal bone, and makes its exit through the stylomastoid foramen; after supplying the stapedius, occipitalis, auricular, stylohyoid, and posterior belly of the digastric muscles; its main trunk ramifies within the parotid gland forming the intraparotid plexus, the various branches of which pass to the muscles of facial expression. SYN: nervus facialis [CN VII] [TA] , motor n. of face, seventh cranial n. [CN VII].
femoral n. [TA] arises as a branch of the lumbar plexus, conveying fibers from the second, third, and fourth lumbar nerves through the substance of the psoas muscle and enters the thigh via the retroinguinal muscular space posterior to the inguinal ligament, lateral to the femoral vessels; it arborizes within the femoral triangle into muscle branches to the sartorius, pectineus, and quadriceps muscles and anterior femoral cutaneous branches to the skin of the anterior and medial region of the thigh; its terminal branch is the saphenous n. by which it supplies the skin of the medial leg and foot. SYN: nervus femoralis [TA] , anterior crural n..
fifth cranial n. [CN V] SYN: trigeminal n. [CN V].
first cranial n. [CN I] SYN: olfactory nerves [CN I].
fourth cranial n. [CN IV] SYN: trochlear n. [CN IV].
fourth lumbar n. [L4] [TA] the ventral branch of the n. is forked to enter into the formation of both lumbar and sacral plexuses. SYN: furcal n., nervus furcalis.
frontal n. [TA] a branch of the ophthalmic n. that divides within the orbit into the supratrochlear and the supraorbital nerves. SYN: nervus frontalis [TA] .
furcal n. SYN: fourth lumbar n. [L4].
Galen n. SYN: communicating branch of internal laryngeal n. with recurrent laryngeal n..
gangliated n. a sympathetic n..
genitocrural n. SYN: genitofemoral n..
genitofemoral n. [TA] arises from the first and second lumbar nerves, passes distally along the anterior surface of psoas major muscle and divides into genital and femoral branches. SYN: nervus genitofemoralis [TA] , genitocrural n..
glossopharyngeal n. [CN IX] [TA] ninth cranial n. that emerges from the rostral end of the medulla and passes through the jugular foramen to supply sensation including taste to the pharynx and posterior third of the tongue; it also carries somatic motor fibers to the stylopharyngeus muscle and secretomotor presynaptic parasympathetic fibers to the otic ganglion for innervation of the parotid gland. SYN: nervus glossopharyngeus [CN IX] [TA] , ninth cranial n. [CN IX].
great auricular n. [TA] arises as a branch of the cervical plexus, conveying fibers from the ventral primary rami of the second and third cervical spinal nerves; supplies the skin of part of the auricle, adjacent portion of the scalp, and that overlying the angle of the jaw; it also innervates the parotid sheath, conveying from it the pain fibers stimulated by stretching of the sheath during parotitis (mumps). SYN: nervus auricularis magnus [TA] .
greater occipital n. [TA] medial branch of the dorsal primary ramus of the second cervical n.; sends branches to the semispinalis capitis and multifidus cervicis, but is mainly sensory, supplying the back part of the scalp, meningeal branches to the posterior cranial fossa, and pain and proprioceptive branches to the first cervical n. for the suboccipital muscles. SYN: nervus occipitalis major [TA] .
greater palatine n. [TA] a branch of the pterygopalatine ganglion that passes inferiorly through the greater palatine canal to supply the mucosa and glands of the hard palate, and the anterior part of the soft palate. SYN: nervus palatinus major [TA] .
greater petrosal n. [TA] a branch from the genu of the facial n. exiting via the hiatus of the facial canal and running in a groove on the anterior surface of the petrous part of the temporal bone beside the foramen lacerum to join the deep petrosal n., thus forming the n. of the pterygoid canal, which passes through the pterygoid canal to reach the pterygopalatine ganglion. SYN: nervus petrosus major [TA] , parasympathetic root of pterygopalatine ganglion&star, greater superficial petrosal n..
greater splanchnic n. [TA] uppermost of the abdominopelvic splanchnic that arises from the fifth or sixth to the ninth or tenth thoracic sympathetic ganglia in the thorax and passes inferiorly along the bodies of the thoracic vertebrae, penetrating the diaphragm to join the celiac plexus; conveys presynaptic sympathetic fibers to the celiac ganglia and visceral afferent fibers from the celiac plexus. SYN: nervus splanchnicus major [TA] .
greater superficial petrosal n. SYN: greater petrosal n..
great sciatic n. SYN: sciatic n..
hemorrhoidal nerves See superior rectal (nervous) plexus, middle rectal (nervous) plexus, inferior anal nerves.
Hering sinus n. SYN: carotid branch of glossopharyngeal n. (CN IX).
hypogastric n. [TA] one of the two n. trunks (right and left) that lead from the superior hypogastric plexus (presacral n.) into the pelvis to join the inferior hypogastric plexuses. SYN: nervus hypogastricus [TA] .
hypoglossal n. [CN XII] [TA] arises from an oblong nucleus in the medulla and emerges by several root filaments between the pyramid and the olive via the preolivary groove; it passes through the hypoglossal canal, then courses downward and forward to supply the intrinsic and four of five extrinsic muscles of the tongue. SYN: nervus hypoglossus [CN XII] [TA] , twelfth cranial n. [CN XII].
iliohypogastric n. [TA] terminal branch, with ilioinguinal n., of the first lumbar n.; it supplies the abdominal muscles and the skin of the lower part of the anterior abdominal wall. SYN: nervus iliohypogastricus [TA] .
ilioinguinal n. [TA] terminal branch, with the iliohypogastric n., the first lumbar n., passes through the inguinal canal and superficial inguinal ring to supply the skin of the upper medial thigh, mons pubis, and scrotum or labia majora. SYN: nervus ilioinguinalis [TA] .
inferior alveolar n. [TA] one of the terminal branches of the mandibular, it enters the mandibular canal to be distributed to the lower teeth, periosteum, and gingiva of the mandible; a branch, the mental n., passes through the mental foramen to supply the skin and mucosa of the lower lip and chin. SYN: nervus alveolaris inferior [TA] , inferior dental n..
inferior anal nerves [TA] several branches of the pudendal n. that pass to the external anal sphincter anoderm and skin of the anal region. SYN: nervi anales inferiores [TA] , inferior rectal nerves&star, nervi rectales inferiores&star, inferior hemorrhoidal nerves.
inferior cervical cardiac n. [TA] a n. passing from the stellate ganglion to the cardiac plexus. SYN: nervus cardiacus cervicalis inferior [TA] .
inferior clunial nerves [TA] branches of the posterior femoral cutaneous n. emerging from beneath the inferior border of the gluteus maximus to supply the skin of the lower half of the gluteal region. SYN: nervi clunium inferiores [TA] .
inferior dental n. SYN: inferior alveolar n..
inferior gluteal n. [TA] arises as a branch of the sacral plexus, conveying fibers from the fifth lumbar and first and second sacral nerves , and supplies the gluteus maximus muscle. It is subject to injury by compression and ischemia in sedentary individuals, resulting in difficulty in rising from a sitting position and difficulty climbing stairs. SYN: nervus gluteus inferior [TA] .
inferior hemorrhoidal nerves SYN: inferior anal nerves.
inferior laryngeal n. [TA] the terminal branch of the recurrent laryngeal n. as the latter passes deep to the inferior pharyngeal constrictor; it supplies the laryngeal mucosa inferior to the vocal folds and all laryngeal muscles except the cricothyroid. SYN: nervus laryngeus inferior [TA] .
inferior lateral brachial cutaneous n. inferior lateral cutaneous n. of arm.
inferior lateral cutaneous n. of arm [TA] cutaneous branch of the radial n. supplying the skin of the lower lateral aspect of the arm; it frequently arises as a branch of the posterior antebrachial n.. SYN: nervus cutaneus brachii lateralis inferior [TA] , inferior lateral brachial cutaneous n.&star.
inferior maxillary n. SYN: mandibular n. [CN V3].
inferior rectal nerves inferior anal nerves.
infraorbital n. [TA] the continuation of the maxillary n. [CN V2] after it has traversed the pterygopalatine fossa and enters the orbit, via the infraorbital fissure, it is then transmitted by the infraorbital canal to reach the face; it supplies the mucosa of the maxillary sinus, the upper incisors, canine and premolars, the upper gums, the inferior eyelid and conjunctiva, part of the nose, and the superior lip. SYN: nervus infraorbitalis [TA] .
infratrochlear n. [TA] a terminal branch of the nasociliary n. running beneath the pulley of the superior oblique muscle to the front of the orbit, and supplying the skin of the eyelids and root of the nose. SYN: nervus infratrochlearis [TA] .
inhibitory n. a n. conveying impulses that diminish functional activity in a part.
intercarotid n. SYN: carotid branch of glossopharyngeal n. (CN IX).
intercostal nerves [TA] ventral primary rami of thoracic nerves [T1–T11]. SYN: nervi intercostales [TA] .
intercostobrachial nerves [TA] lateral cutaneous branches of the second and third intercostal nerves that pass to the skin of the medial side of the arm. SYN: nervi intercostobrachiales [TA] , intercostohumeral nerves.
intercostohumeral nerves SYN: intercostobrachial nerves.
intermediary n. SYN: intermediate n..
intermediate n. [TA] a root of the facial n. containing sensory fibers for taste from the anterior 2/3 of tongue whose cell bodies are located in the geniculate ganglion and presynaptic parasympathetic autonomic fibers whose cell bodies are located in the superior salivatory nucleus, i.e., the fibers are eventually conveyed via the chorda tympani branch of the facial n. to the lingual n.. SYN: nervus intermedius [TA] , intermediary n., portio intermedia, Wrisberg n. (2) .
intermediate dorsal cutaneous n. [TA] the lateral terminal branch of the superficial fibular (peroneal) n., supplying the dorsum of the foot and dorsal digital nerves to the toes (except for adjacent parts of great and second toes). SYN: nervus cutaneus dorsalis intermedius [TA] .
intermediate supraclavicular n. [TA] one of several nerves arising from the C-3–C-4 part of the cervical plexus that run across the top of the shoulder and pass down across the shaft of the clavicle to supply the skin of the top of the shoulder and in the infraclavicular region. SYN: nervus supraclavicularis intermedius [TA] , middle supraclavicular n..
internal carotid n. [TA] the cephalic arterial ramus conveying postsynaptic sympathetic fibers from the superior cervical ganglion to the internal carotid artery to form the internal carotid plexus. SYN: nervus caroticus internus [TA] .
internal saphenous n. SYN: saphenous n..
interosseous n. of leg SYN: crural interosseous n..
Jacobson n. SYN: tympanic n..
jugular n. [TA] a communicating branch between the superior cervical ganglion of the sympathetic n., the superior ganglion of the vagus n., and the inferior ganglion of the glossopharyngeal n.. SYN: nervus jugularis [TA] .
lacrimal n. [TA] a branch of the ophthalmic n. [CN V1] supplying sensory fibers to the lateral part of the upper eyelid, conjunctiva, and lacrimal gland. The secretomotor fibers of the latter were conveyed to the lacrimal n. by the communicating branch of the zygomatic n. (a branch of the maxillary n. [CN V2]. SYN: nervus lacrimalis [TA] .
Latarget n. 1. SYN: superior hypogastric (nervous) plexus. 2. terminal branch of anterior vagal trunk that runs along lesser curvature of the stomach to within a few centimeters of the gastroduodenal junction, but apparently never reaching the pyloric sphincter.
lateral ampullar n. [TA] a branch of the utriculoampullar n. that supplies the crista ampullaris of the lateral semicircular duct. SYN: nervus ampullaris lateralis [TA] .
lateral antebrachial cutaneous n. lateral cutaneous n. of forearm.
lateral anterior thoracic n. SYN: lateral pectoral n..
lateral cutaneous n. of calf SYN: lateral sural cutaneous n..
lateral cutaneous n. of forearm [TA] the terminal cutaneous branch of the musculocutaneous n. that emerges between biceps brachii and brachialis muscles to supply the skin of the radial side of the forearm. SYN: nervus cutaneus antebrachii lateralis [TA] , lateral antebrachial cutaneous n.&star.
lateral cutaneous n. of thigh [TA] arises from the lumbar plexus, conveying fibers from the second and third lumbar nerves, supplies the skin of the anterolateral and lateral surfaces of the thigh. SYN: nervus cutaneus femoris lateralis [TA] , lateral femoral cutaneous n.&star.
lateral dorsal cutaneous n. [TA] the continuation of the sural n. in the foot, supplying the lateral margin and dorsum. SYN: nervus cutaneus dorsalis lateralis [TA] , dorsal lateral cutaneous n..
lateral femoral cutaneous n. lateral cutaneous n. of thigh.
lateral pectoral n. [TA] a n. that arises from the lateral cord of the brachial plexus usually passing medial to pectoralis minor to supply the sternoclavicular head of pectoralis major. SYN: nervus pectoralis lateralis [TA] , lateral anterior thoracic n..
lateral plantar n. [TA] one of two terminal branches of the tibial n.; it courses along the lateral side of the sole, dividing into superficial and deep branches; it supplies the skin of the lateral aspect of the sole and the lateral one and one-half toes; it innervates the intrinsic muscles of the plantar part of the foot with the exception of the abductor hallucis and the flexor digitorum brevis; its distribution in the foot is very similar to that of the ulnar n. in the hand. SYN: nervus plantaris lateralis [TA] .
lateral supraclavicular n. [TA] one of several branches of the C-3–C-4 portion of the cervical plexus that descend to the skin over the acromion and deltoid region. SYN: nervus supraclavicularis lateralis [TA] , posterior supraclavicular n..
lateral sural cutaneous n. [TA] it arises from the common fibular (peroneal) in the popliteal space and is distributed to the skin of the inferolateral surface of the calf. SYN: nervus cutaneus surae lateralis [TA] , lateral cutaneous n. of calf.
least splanchnic n. [TA] one of the abdominopelvic splanchnic nerves arising in the thorax and penetrating the diaphragm to supply presynaptic sympathetic fibers for the renal plexus; often combined with the lesser splanchnic n., but occasionally existing as an independent n.. SYN: nervus splanchnicus imus [TA] , lowest splanchnic n.&star, smallest splanchnic n..
lesser internal cutaneous n. SYN: medial cutaneous n. of arm.
lesser occipital n. [TA] arises from cervical plexus, conveying fibers from the ventral primary rami of the second and third cervical nerves; supplies the skin of the posterior surface of the auricle and the adjacent portion of the scalp posterior to the auricle. SYN: nervus occipitalis minor [TA] .
lesser palatine nerves [TA] usually two, these nerves emerge through the lesser palatine foramina and supply the mucosa and glands of the soft palate and uvula; they are branches of the pterygopalatine ganglion and contain postsynaptic parasympathetic and sensory fibers of the maxillary n.. SYN: nervi palatini minores [TA] .
lesser petrosal n. [TA] the parasympathetic root of the otic ganglion, derived from the tympanic plexus; it leaves the tympanic cavity through the canal for the lesser petrosal n. and passes within the cranium to the sphenopetrosal fissure, or to the foramen ovale, or to the petrosal foramen through which it descends to reach the otic ganglion; conveys presynaptic parasympathetic fibers from the glossopharyngeal n. concerned with secretomotor innervation of the parotid gland. SYN: nervus petrosus minor [TA] , parasympathetic root of otic ganglion&star, radix parasympathica ganglii otici&star, lesser superficial petrosal n..
lesser splanchnic n. [TA] one of the abdominopelvic splanchnic nerves arising in the thorax from the last two thoracic sympathetic ganglia and passing through the diaphragm to the aorticorenal ganglion; conveys presynaptic sympathetic fibers and visceral afferent fibers. SYN: nervus splanchnicus minor [TA] .
lesser superficial petrosal n. SYN: lesser petrosal n..
lingual n. [TA] one of the branches of the mandibular n. [CN V3], passing medial to the lateral pterygoid muscle, between the medial pterygoid and the mandible, and beneath the mucous membrane of the floor of the mouth to the side of the tongue over the anterior two-thirds of which it is distributed: it supplies also the mucous membrane of the floor of the mouth. It passes close to the lingual side of the roots of the second and third lower molar teeth and is endangered during tooth extractions. SYN: nervus lingualis [TA] .
long buccal n. SYN: buccal n..
long ciliary n. [TA] one of two or three branches of the nasociliary n., which bypass the ciliary ganglion, supplying postsynaptic sympathetic fibers for the dilator pupillae muscle and sensory fibers for the ciliary muscles, iris, and cornea. SYN: nervus ciliaris longus [TA] .
long saphenous n. SYN: saphenous n..
long subscapular n. SYN: thoracodorsal n..
long thoracic n. [TA] arises from the fifth, sixth, and seventh cervical nerves (roots of brachial plexus), descends the neck behind the brachial plexus, and is distributed to the serratus anterior muscle; it is somewhat unusual in that it courses on the superficial aspect of the muscle it supplies; its paralysis results in “winged scapula.” SYN: nervus thoracicus longus [TA] , Bell respiratory n., external respiratory n. of Bell, posterior thoracic n..
lowest splanchnic n. least splanchnic n..
Ludwig n. SYN: aortic n..
lumbar nerves [L1–L5] five bilaterally paired spinal nerves emerging from the lumbar portion of the spinal cord; the first four nerves enter into the formation of the lumbar plexus, the fourth and fifth into that of the sacral plexus. SYN: nervi lumbales.
lumbar splanchnic nerves [TA] branches arising from the medial aspect of the lumbar sympathetic trunks that pass anteriorly and medially to convey presynaptic sympathetic fibers to, and visceral afferents from, the celiac, intermesenteric, aortic, and superior hypogastric plexuses. SYN: nervi splanchnici lumbales [TA] .
lumboinguinal n. femoral branch of genitofemoral n. See genitofemoral n..
mandibular n. [CN V3] [TA] the third division of the trigeminal n. formed by the union of sensory fibers from the trigeminal ganglion and the motor root of the trigeminal n. in the foramen ovale, through which the n. emerges; its branches are: meningeal, masseteric, deep temporal, lateral and medial pterygoid, buccal, auriculotemporal, lingual, and inferior alveolar; its sensory fibers are distributed to the auricle, external acoustic meatus, tympanic membrane, temporal region, cheek, skin overlying the mandible (except its angle), anterior 2/3 of tongue, floor of mouth, lower teeth, and gingiva; its motor fibers innervate all the muscles of mastication plus the mylohyoid, anterior belly of the digestive, and the tensores veli palati and tympani. SYN: nervus mandibularis [CN V3] [TA] , inferior maxillary n..
masseteric n. [TA] a muscular branch of the mandibular n. [CN V3] passing through the mandibular notch to the medial surface of the masseter muscle that it supplies and the temporomandibular joint. SYN: nervus massetericus [TA] .
masticator n. SYN: motor root of trigeminal n..
maxillary n. [CN V2] the second division of the trigeminal n., passing from the trigeminal ganglion in the middle cranial fossa through the foramen rotundum into the pterygopalatine fossa, where it gives off ganglionic branches to the pterygopalatine ganglion and continues forward to give off the zygomatic n. and enter the orbit, where it continues as the infraorbital n.. Its sensory fibers are distributed to the skin and conjunctiva of the lower eyelid, the skin and mucosa of the upper lip and cheek, the palate, upper teeth and gingiva, the maxillary sinus, wings of the nose, and posterior/interior nasal cavity. SYN: nervus maxillaris [CN V2] [TA] , superior maxillary n..
medial antebrachial cutaneous n. medial cutaneous n. of forearm.
medial anterior thoracic n. SYN: medial pectoral n..
medial brachial cutaneous n. medial cutaneous n. of arm.
medial clunial nerves [TA] terminal branches of the dorsal primary rami of the sacral nerves, supplying the skin of the midgluteal region. SYN: nervi clunium medii [TA] , middle cluneal nerves.
medial crural cutaneous n. medial cutaneous n. of leg.
medial cutaneous n. of arm [TA] arises from the medial cord of the brachial plexus, unites in the axilla with the lateral cutaneous branch of the second intercostal n., and supplies the skin of the medial side of the arm. SYN: nervus cutaneus brachii medialis [TA] , medial brachial cutaneous n.&star, lesser internal cutaneous n., Wrisberg n. (1) .
medial cutaneous n. of forearm [TA] arises from the medial cord of the brachial plexus, passes downward in company with the brachial artery and then the basilic vein, and supplies the skin of the anterior and ulnar surfaces of the forearm. SYN: nervus cutaneus antebrachii medialis [TA] , medial antebrachial cutaneous n.&star.
medial cutaneous n. of leg [TA] branches of saphenous n. distributed to the skin of the medial side of the leg. SYN: rami cutanei cruris mediales nervi sapheni [TA] , medial crural cutaneous n.&star, medial crural cutaneous branches of saphenous n..
medial dorsal cutaneous n. [TA] the medial terminal branch of the superficial fibular (peroneal) n., supplying the dorsum of the foot and dorsal nerves to the toes (except adjacent sides of great and second toes). SYN: nervus cutaneus dorsalis medialis [TA] , dorsal medial cutaneous n..
medial pectoral n. [TA] a n. that arises from the medial cord of the brachial plexus to supply the pectoral muscles; usually pierces pectoralis minor, then continues to supply mainly the sternocostal portion of pectoralis major. SYN: nervus pectoralis medialis [TA] , medial anterior thoracic n..
medial plantar n. [TA] one of the two terminal branches of the tibial n.; it courses along the medial aspect of the sole to supply the abductor hallucis and flexor digitorum brevis and, by way of common and proper digital branches, to innervate the skin of the medial part of the foot and medial three and one-half toes. SYN: nervus plantaris medialis [TA] .
medial popliteal n. SYN: tibial n..
medial supraclavicular n. [TA] one of several nerves arising from the C3–C4 loop of the cervical plexus that supply the skin over the medial end of the clavicle and upper medial part of the thorax. SYN: nervus supraclavicularis medialis [TA] , anterior supraclavicular n..
medial sural cutaneous n. [TA] arises from the tibial n. in the popliteal space, passes down the calf between the two heads of the gastrocnemius and unites in the middle of the leg with the communicating branch of the common peroneal to form the sural n., distributed to the skin of the distal and lateral surfaces of the leg and ankle. SYN: nervus cutaneus surae medialis [TA] , popliteal communicating n., tibial communicating n..
median n. [TA] formed by the union of medial and lateral roots from the medial and lateral cords of the brachial plexus, respectively; it supplies all the muscles in the anterior compartment of the forearm with the exception of the flexor carpi ulnaris and ulnar half of the flexor digitorum profundus; it passes through the carpal tunnel to supply the thenar muscles (except adductor pollicis and the deep head of flexor pollicis brevis) via its recurrent thenar branch; its sensory fibers are distributed to the skin of the palmar and distal dorsal aspects of the radial three and one-half digits and adjacent palm. The median n. is most commonly injured through compression in carpal tunnel syndrome, resulting in a loss of ability to oppose the thumb (“ape hand”) and loss of sensation over the radial portion of the hand. SYN: nervus medianus [TA] .
mental n. [TA] a branch of the inferior alveolar n., arising in the mandibular canal and passing through the mental foramen to the chin and lower lip. SYN: nervus mentalis [TA] .
middle cervical cardiac n. [TA] one of the cardiopulmonary splanchnic nerves conveying postsynaptic sympathetic fibers running downward, from the middle cervical ganglion along the subclavian artery (on the left) or the brachiocephalic (on the right side) to join the cardiac plexus. SYN: nervus cardiacus cervicalis medius [TA] .
middle cluneal nerves SYN: medial clunial nerves.
middle meningeal n. SYN: meningeal branch of maxillary n..
middle supraclavicular n. SYN: intermediate supraclavicular n..
mixed n. [TA] a n. containing both afferent and efferent fibers. SYN: nervus mixtus [TA] .
motor n. [TA] a n. composed mostly or entirely of efferent (motor) n. fibers conveying impulses that excites muscular contraction; motor nerves in the autonomic nervous system also elicit secretions from glandular epithelia.
motor n. of face SYN: facial n. [CN VII].
musculocutaneous n. [TA] arises from lateral cord of the brachial plexus, passes through the coracobrachialis muscle, and then downward between the brachialis and biceps, supplying these three muscles and being continued distally as the lateral cutaneous n. of the forearm. SYN: nervus musculocutaneus [TA] .
musculocutaneous n. of leg SYN: superficial fibular n..
musculospiral n. SYN: radial n..
myelinated n. a peripheral n. whose axons are surrounded by layers of Schwann cell membranes that form the myelin sheath; also called medullated nerves.
mylohyoid n. SYN: n. to mylohyoid.
n. to mylohyoid [TA] a small branch of the inferior alveolar n. given off posteriorly just before the n. enters the mandibular foramen, distributed to the anterior belly of the digastric muscle and to the mylohyoid muscle. SYN: nervus mylohyoideus [TA] , mylohyoid n..
nasal n. SYN: nasociliary n..
nasociliary n. [TA] a branch of the ophthalmic n. [CN V1]in the superior orbital fissure, passing through the orbit, giving rise to the communicating branch to the ciliary ganglion, the long ciliary nerves, the posterior and anterior ethmoidal nerves, and terminating as the infratrochlear and nasal branches, which supply the mucous membrane of the nose, the skin of the tip of the nose, and the conjunctiva. SYN: nervus nasociliaris [TA] , nasal n..
nasopalatine n. [TA] a branch from the pterygopalatine ganglion, passing through the sphenopalatine foramen, crossing to and then down the nasal septum, and through the incisive foramen to supply the mucous membrane of the hard palate. SYN: nervus nasopalatinus [TA] .
ninth cranial n. [CN IX] SYN: glossopharyngeal n. [CN IX].
obturator n. [TA] arises from the lumbar plexus, conveying fibers from the second, third, and fourth lumbar nerves in the psoas muscle, crosses the brim of the pelvis, and enters the thigh through the obturator canal; it supplies muscles of the medial compartment of the thigh (adductors of thigh at the hip joint) and terminates as the cutaneous branch of the obturator n., supplying a small area of medial thigh above knee. SYN: nervus obturatorius [TA] .
oculomotor n. [CN III] [TA] the third cranial n., it supplies all the extrinsic muscles of the eye, except the lateral rectus and superior oblique; it also supplies the levator palpebrae superioris and conveys presynaptic parasympathetic fibers to the ciliary ganglion for innervation of the ciliary muscle and sphincter pupillae; its origin is in the midbrain below the cerebral aqueduct; it emerges from the brain in the interpeduncular fossa, pierces the dura mater to the side of the posterior clinoid process, passes in the lateral wall of the cavernous sinus, and enters the orbit through the superior orbital fissure. SYN: nervus oculomotorius [CN III] [TA] , motor oculi, oculomotorius, third cranial n. [CN III].
olfactory nerves [CN I] [TA] collective term denoting the numerous olfactory filaments: slender fascicles each composed of the thin, unmyelinated axons of 8 to 12 of the bipolar olfactory receptor cells in the olfactory portion of the nasal mucosa; the olfactory filaments pass through the cribriform plate of the ethmoid bone and enter the olfactory bulb, where they terminate in synaptic contact with mitral cells, tufted cells, and granule cells. SEE ALSO: olfactory tract. SYN: fila olfactoria [TA] , nervus olfactorii [CN I] [TA] , first cranial n. [CN I], n. of smell, olfactory fila.
ophthalmic n. [CN V1] [TA] a branch of the trigeminal n. that passes forward from the trigeminal ganglion in the lateral wall of the cavernous sinus, entering the orbit through the superior orbital fissure; through its branches, frontal, lacrimal, and nasociliary, it supplies sensation to the orbit and its contents, the anterior part of the nasal cavity, and the skin of the nose and forehead. SYN: nervus ophthalmicus [CN V1] [TA] .
optic n. [CN II] [TA] although classified as a cranial n., it is actually an extension of the forebrain; it conveys afferent fibers from the ganglion cells of the retina, it passes out of the orbit through the optic canal to the chiasm, where part of the fibers cross to the opposite side and pass through the optic tract to the geniculate bodies, superior colliculus, and the pretectum. SYN: nervus opticus [CN II] [TA] , second cranial n. [CN II].
orbital n. SYN: zygomatic n..
parasympathetic n. one of the nerves of the parasympathetic nervous system.
pathetic n. SYN: trochlear n. [CN IV].
pelvic splanchnic nerves [TA] visceral branches from the ventral primary rami of the second, third, and fourth sacral spinal nerves that join the inferior hypogastric plexus to form the pelvic plexuses, to and from which they convey presynaptic parasympathetic and sensory fibers, respectively. SYN: nervi pelvici splanchnici [TA] , parasympathetic root of pelvic ganglia&star, radices parasympathicae gangliorum pelvicorum&star, nervi erigentes.
perineal nerves [TA] the superficial terminal branches of the pudendal n., supplying most of the muscles of the perineum (deep branch) as well as the skin of that region (superficial branch). SYN: nervi perineales [TA] .
peroneal communicating n. SYN: sural communicating branch of common fibular n..
pharyngeal n. [TA] branch of pterygopalatine ganglion passing posteriorly through pharyngeal canal to supply postsynaptic parasympathetic fibers to mucus glands of nasopharynx. SYN: nervus pharyngeus [TA] , Bock n., pharyngeal branch of pterygopalatine ganglion, ramus pharyngeus ganglii pterygopalatini.
phrenic n. [TA] arises from the cervical plexus, chiefly conveying fibers from the fourth cervical n., passes downward in front of the anterior scalene muscle and enters the thorax between the subclavian artery and vein behind the sternoclavicular articulation; it then passes in front of the root of the lung to the diaphragm; it is mainly the motor n. of the diaphragm but sends sensory fibers to the mediastinal parietal pleura, the pericardium, the diaphragmatic pleura and peritoneum, and branches (phrenicoabdominales branches) that communicate with branches from the celiac plexus. SYN: nervus phrenicus [TA] .
pneumogastric n. SYN: vagus n. [CN X].
popliteal communicating n. SYN: medial sural cutaneous n..
posterior ampullar n. [TA] a branch of the vestibular part of the eighth n. that supplies the crista ampullaris of the posterior semicircular duct. SYN: nervus ampullaris posterior [TA] .
posterior antebrachial n. SYN: posterior interosseous n..
posterior antebrachial cutaneous n. posterior cutaneous n. of forearm.
posterior auricular n. [TA] the first extracranial branch of the facial n., it passes behind the ear, supplying the auricularis posterior, intrinsic muscles of the auricle and, through its occipital branch, the occipital belly of the occipitofrontalis muscle. SYN: nervus auricularis posterior [TA] .
posterior brachial cutaneous n. posterior cutaneous n. of arm.
posterior cutaneous n. of arm [TA] a branch of the radial n. supplying the skin of the posterior surface of the arm. SYN: nervus cutaneus brachii posterior [TA] , posterior brachial cutaneous n.&star.
posterior cutaneous n. of forearm [TA] a branch of the radial n. supplying the skin of the dorsal surface of the forearm. SYN: nervus cutaneus antebrachii posterior [TA] , posterior antebrachial cutaneous n.&star.
posterior cutaneous n. of thigh [TA] arises as a branch of the sacral plexus, conveying fibers from the ventral rami of first three sacral nerves; supplies the skin of the posterior surface of the thigh and of the popliteal region (S1 and S2 component); it gives off a perineal branch (S3 component) that passes to the lateral aspect of the scrotum or labia majora. SYN: nervus cutaneus femoris posterior [TA] , posterior femoral cutaneous n.&star, small sciatic n..
posterior ethmoidal n. [TA] a branch of the nasociliary n. providing sensory innervation to the sphenoidal sinus and the posterior ethmoidal air cells. SYN: nervus ethmoidalis posterior [TA] .
posterior femoral cutaneous n. posterior cutaneous n. of thigh.
posterior inferior nasal nerves [TA] branches of greater palatine n. to posterior inferior lateral wall of nasal cavity, including posterior aspect of mucosa over posterior portion of inferior nasal concha and meatus; may arise independently from pterygopalatine ganglion. SYN: rami nasales posteriores inferiores nervi palatini majoris [TA] , posterior inferior nasal branches of greater palatine n..
posterior interosseous n. [TA] the terminal portion of the deep branch of the radial n.; arises in the cubital region, penetrating and supplying the supinator and continuing with the posterior interosseous artery to supply all the extensor muscles in the forearm. SYN: nervus interosseus antebrachii posterior [TA] , dorsal interosseous n., nervus antebrachii posterior, nervus interosseus dorsalis, nervus interosseus posterior, posterior antebrachial n..
posterior labial nerves [TA] terminal branches of the superficial perineal n., supplying the skin of the posterior portion of the labia and the vestibule of the vagina, corresponding to the posterior scrotal nerves in the male. SYN: nervi labiales posteriores [TA] .
posterior scapular n. SYN: dorsal scapular n..
posterior scrotal nerves [TA] several terminal branches of the superficial perineal n. supplying the skin of the posterior portion of the scrotum, corresponding to the posterior labial nerves in the female. SYN: nervi scrotales posteriores [TA] .
posterior supraclavicular n. SYN: lateral supraclavicular n..
posterior thoracic n. SYN: long thoracic n..
presacral n. superior hypogastric (nervous) plexus.
pressor n. an afferent n., stimulation of which excites a reflex vasoconstriction, thereby raising the blood pressure.
pressoreceptor n. a n. composed of afferent fibers the endings of which are sensitive to increases in mechanical pressure; the term specifically refers to sensory nerves innervating the walls of hollow organs. SYN: baroreceptor n..
proper palmar digital nerves [TA] the palmar nerves of the digits of the hand derived from common palmar digital nerves; each n. supplies a palmar quadrant of a digit and a part of the dorsal surface of the distal phalanx. SYN: nervi digitales palmares proprii [TA] .
proper plantar digital nerves [TA] the ten nerves derived from the common plantar digital nerves; each n. supplies a plantar quadrant of a toe and part of the dorsal surface of the distal phalanx. SYN: nervi digitales plantares proprii [TA] .
pterygoid n. [TA] one of two motor branches, the nerves to the lateral and medial pterygoid muscles, from the mandibular n., supplying muscles with fibers of the motor root of the trigeminal n.. SYN: nervus pterygoideus [TA] .
n. of pterygoid canal [TA] the n. constituting the parasympathetic and sympathetic root of the pterygopalatine ganglion; it is formed in the region of the foramen lacerum by the union of the greater and deep petrosal nerves and runs through the pterygoid canal to the pterygopalatine fossa. SYN: nervus canalis pterygoidei [TA] , facial root, radix facialis, vidian n..
pterygopalatine nerves SYN: sensory root of pterygopalatine ganglion.
pudendal n. [TA] branch of the sacral plexus formed by fibers from the ventral primary rami of the second, third, and fourth sacral spinal nerves; it exits the pelvis via the greater sciatic foramen, passes posterior to the sacrospinous ligament, and accompanies the internal pudendal artery, into the perineum via the lesser sciatic foramen; it gives off inferior rectal nerves, then courses through the pudendal canal in the lateral wall of the ischiorectal fossa, terminating as the dorsal n. of the penis or of the clitoris. SYN: nervus pudendus [TA] , plexus pudendus nervosus, pudic n..
pudic n. SYN: pudendal n..
radial n. [TA] arises from the posterior cord of the brachial plexus conveying fibers from all roots of the plexus; it curves around the posterior surface of the humerus and passes down to the cubital fossa where it divides into its two terminal branches, the cutaneous superficial branch and the motor deep branch; it supplies the muscles of the posterior compartments of the arm and forearm and overlying skin. The radial n. is most commonly injured by fractures of the middle 1/3 of the humerus, resulting in a loss of extension at the wrist (“wrist drop”). SYN: nervus radialis [TA] , musculospiral n..
recurrent n. SYN: recurrent laryngeal n..
recurrent laryngeal n. [TA] a branch of the vagus n. curving upward, on the right side around the root of the subclavian artery, on the left side around the arch of the aorta, then passing superiorly, posterior to the common carotid artery between the trachea and the esophagus to the larynx; it supplies cardiac, tracheal, and esophageal branches and terminates as the inferior laryngeal n.. SYN: nervus laryngeus recurrens [TA] , recurrent n..
recurrent meningeal n. meningeal branches of 1) mandibular, 2) maxillary, 3) ophthalmic, and 4) spinal nerves.
n. to rhomboid SYN: dorsal scapular n..
saccular n. [TA] a branch of the inferior part of the vestibular n. going to the macula of the sacculus. SYN: nervus saccularis [TA] .
sacral splanchnic nerves [TA] branches from the sacral sympathetic trunk that pass to the inferior hypogastric plexus; part of the abdominopelvic (sympathetic) splanchnic nerves, but their specific function is unclear. They tend to be confused with the pelvic splanchnic nerves, which are much more significant structures. SYN: nervi splanchnici sacrales [TA] .
sacral nerves [S1–S5] five nerves issuing from the sacral foramina on either side; the ventral branches of the first three enter into the formation of the sacral plexus, and the last two into the coccygeal plexus. SYN: nervi sacrales [S1–S5].
saphenous n. [TA] a branch of the femoral, extending from the femoral triangle to the foot, becoming subcutaneous on the medial side of the knee; it supplies cutaneous branches to the skin of the leg and foot, by way of infrapatellar and medial crural branches. SYN: nervus saphenus [TA] , internal saphenous n., long saphenous n..
sciatic n. [TA] arises as the major product of the sacral plexus, exits the pelvis via the greater sciatic foramen, and descends in the posterior compartment of the thigh, deep to the long head of biceps femoris n.; at the apex of the popliteal fossa it divides into the common peroneal and tibial nerves, although the two may separate at higher levels. SYN: nervus ischiadicus [TA] , great sciatic n., nervus sciaticus.
second cranial n. [CN II] SYN: optic n. [CN II].
secretomotor n. SYN: secretory n..
secretory n. a n. conveying impulses that excite functional activity in a gland. SYN: secretomotor n..
sensory n. an afferent n. conveying impulses that are processed by the central nervous system so as to become part of the organism's perception of self and its environment.
seventh cranial n. [CN VII] SYN: facial n. [CN VII].
short ciliary n. [TA] one of a number of branches passing from the ciliary ganglion to the eyeball, supplying the ciliary muscles, iris, and tunics of the eyeball. SYN: nervus ciliaris brevis [TA] .
short saphenous n. SYN: sural n..
sinus n. of Hering SYN: carotid branch of glossopharyngeal n. (CN IX).
sinuvertebral nerves SYN: meningeal branch of spinal nerves.
sixth cranial n. [CN VI] SYN: abducent n. [CN VI].
small deep petrosal n. SYN: caroticotympanic nerves.
smallest splanchnic n. SYN: least splanchnic n..
small sciatic n. SYN: posterior cutaneous n. of thigh.
n. of smell SYN: olfactory nerves [CN I].
somatic n. one of the nerves of parietal sensation or voluntary motion, as distinguished from the visceral sensory, involuntary motor, and secretory nerves.
spinal nerves [TA] the nerves emerging from the spinal cord; there are 31 pairs, each arising from the cord by rootlets that converge to form two roots, anterior (ventral or motor) and posterior (dorsal or sensory); the latter type is provided with a circumscribed enlargement, the spinal (dorsal root) ganglion; the two roots unite in the intervertebral foramen, and the mixed spinal n. almost immediately divides again into anterior and posterior (primary) rami, the former supplying the anterolateral trunk and the limbs, the latter the true muscles and overlying skin of the back. SYN: nervi spinales [TA] .
spinal accessory n. SYN: accessory n. [CN XI].
splanchnic n. one of the nerves supplying the viscera. There are three groups of splanchnic nerves: cardiopulmonary splanchnic nerves that convey postsynaptic sympathetic fibers to thoracic viscera; abdominopelvic nerves that convey presynpatic sympathetic fibers to the sympathetic ganglia of the abdominopelvic cavity; and pelvic splanchnic nerves that convey presynaptic parasympathetic fibers to the pelvic ganglia. See also entries under the individual listings for the splanchnic nerves mentioned.
n. to stapedius muscle [TA] a branch of the facial arising in the facial canal and innervating the stapedius muscle. SYN: nervus stapedius [TA] .
statoacoustic n. SYN: vestibulocochlear n. [CN VIII].
subclavian n. [TA] a branch from the superior trunk of the brachial plexus supplying the subclavius muscle. SYN: nervus subclavius [TA] .
subcostal n. [TA] the ventral ramus of the twelfth thoracic n.; it courses below the last rib paralleling the course of the intercostal nerves superior to it; it supplies parts of the abdominal muscles and gives off cutaneous branches to the skin of the lowermost ventrolateral abdominal wall and to the superolateral gluteal region. SYN: nervus subcostalis [TA] .
sublingual n. [TA] a branch of the lingual to the sublingual gland and mucosa of the floor of the mouth. SYN: nervus sublingualis [TA] .
suboccipital n. [TA] dorsal ramus of the first cervical n., passing through the suboccipital triangle and sending branches to the rectus capitis posterior major and minor, obliquus capitis superior and inferior, rectus capitis lateralis, and semispinalis capitis; the first cervical spinal n. is generally considered to have only motor fibers, but the suboccipital n. receives sensory fibers for proprioception via a communicating branch from the second cervical spinal n.. SYN: nervus suboccipitalis [TA] .
subscapular nerves [TA] two branches of the posterior cord of the brachial plexus, an upper and lower, supplying the subscapularis muscle; the lower subscapular n. also supplies the teres major muscle. SYN: nervi subscapulares [TA] .
sudomotor nerves nerves containing autonomic (general visceral efferent–postganglionic) fibers that innervate sweat glands.
superficial cervical n. SYN: transverse cervical n..
superficial fibular n. [TA] a branch of the common fibular (peroneal) n. that passes downward in the lateral compartment of the leg to supply the fibularis (peroneus) longus and brevis muscles and terminate as the intermediate and medial dorsal cutaneous nerves supplying the skin of the dorsum of the foot and toes (except for adjacent sides of great and second toes). SYN: nervus fibularis superficialis [TA] , nervus peroneus superficialis&star, superficial peroneal n.&star, musculocutaneous n. of leg.
superficial peroneal n. superficial fibular n..
superior alveolar nerves [TA] three branches (posterior, middle, and anterior) of the maxillary n. (or its continuation as the infraorbital n.) that enter the maxilla to supply the mucosa of the maxillary sinus, upper teeth, and gingiva. SYN: nervi alveolares superiores [TA] , superior dental nerves.
superior cervical cardiac n. [TA] the uppermost of the cardiopulmonary splanchnic nerves that arises from the lower part of the superior cervical ganglion and passes down to form, with branches of the vagus, the cardiac plexus. SYN: nervus cardiacus cervicalis superior [TA] .
superior clunial nerves [TA] terminal branches of the dorsal primary rami of the lumbar nerves, supplying the skin of the upper half of the gluteal region. SYN: nervi clunium superiores [TA] .
superior dental nerves SYN: superior alveolar nerves.
superior gluteal n. [TA] arises from sacral plexus, conveying fibers from the fourth and fifth lumbar and first sacral nerves, and supplies the gluteus medius and minimus and tensor fasciae latae muscles (abductors and medial rotators of the hip joint). A lesion of this n. causes the pelvis to drop on the unsupported side when the foot is lifted off the ground (Trendelenburg sign). SYN: nervus gluteus superior [TA] .
superior laryngeal n. [TA] a branch of the vagus n. at the inferior ganglion; at the thyroid cartilage it divides into two branches: the internal laryngeal n., a sensory branch that supplies the mucous membrane of the larynx superior to the vocal folds, and the external laryngeal n., a motor branch that supplies the inferior pharyngeal constrictor and the cricothyroid muscle. SYN: nervus laryngeus superior [TA] .
superior lateral brachial cutaneous n. upper lateral cutaneous n. of arm.
superior maxillary n. SYN: maxillary n. [CN V2].
supraorbital n. [TA] a branch of the frontal n. leaving the orbit through the supraorbital foramen or notch and dividing into branches distributed to the forehead and scalp, upper eyelid, and frontal sinus. SYN: nervus supraorbitalis [TA] .
suprascapular n. [TA] arises from the upper trunk of the brachial plexus (fifth and sixth cervical spinal nerves), passes downward parallel to the cords of the brachial plexus, then through the scapular notch, supplying the supraspinatus and infraspinatus muscles, and also sending branches to the shoulder joint. It is vulnerable to injury in fractures of the middle 1/3 of the clavicle; a lesion of the suprascapular n. results in a loss of lateral rotation at the shoulder so that when relaxed the limb rotates medially (waiter's tip position); ability to initiate abduction is also affected. SYN: nervus suprascapularis [TA] .
supratrochlear n. [TA] a branch of the frontal n. supplying the medial part of the upper eyelid, the central part of the skin of the forehead, and the root of the nose. SYN: nervus supratrochlearis [TA] .
sural n. [TA] formed by the union of the medial sural cutaneous from the tibial and the peroneal communicating branch of the common peroneal n., usually about the middle of the calf, although this is highly variable; thence it accompanies the small saphenous vein around the lateral malleolus to the dorsum of the foot as the lateral dorsal cutaneous n.. SYN: nervus suralis [TA] , external saphenous n., short saphenous n..
sympathetic n. one of the nerves of the sympathetic nervous system.
temporomandibular n. SYN: zygomatic n..
n. to tensor tympani (muscle) [TA] a branch of the mandibular n. conveying fibers from the motor root of the trigeminal n. that pass through the otic ganglion without synapse to supply the tensor tympani muscle. SYN: nervus musculi tensoris tympani [TA] .
n. to tensor veli palatini (muscle) [TA] a branch of the mandibular n. conveying fibers from the motor root of the trigeminal n. that pass through the otic ganglion without synapse to supply the tensor veli palatini muscle. SYN: nervus musculi tensoris veli palatini [TA] .
tenth cranial n. [CN X] SYN: vagus n. [CN X].
tentorial n. [TA] the meningeal branch arising in a recurrent fashion from the intracranial portion of the ophthalmic n. supplying the tentorium cerebelli and supratentorial falx cerebri. SYN: ramus meningeus recurrens nervi ophthalmici [TA] , ramus tentorii&star, nervus tentorii.
terminal n. [TA] delicate plexiform n. strands passing parallel and medial to the olfactory tracts, distributing peripherally with the olfactory nerves and passing centrally into the anterior perforated substance; they are considered to have an autonomic function, but the exact nature of this is unknown. SYN: nervus terminalis [TA] .
third cranial n. [CN III] SYN: oculomotor n. [CN III].
third occipital n. [TA] medial branch of the dorsal primary ramus of the third cervical n.; this is usually joined with the greater occipital, but may exist as an independent n. supplying cutaneous branches to the scalp and nucha. SYN: nervus occipitalis tertius [TA] .
thoracic cardiac nerves SYN: thoracic cardiac branches of thoracic ganglia, under branch.
thoracic splanchnic nerves splanchnic nerves arising from the thoracic portion of the sympathetic trunks; the upper thoracic splanchnic nerves (from T1 to T4 or 5) pass to viscera above the diaphragm (mainly heart, lungs, and esophagus) and so are cardiopulmonary splanchnic nerves; the lower thoracic splanchnic nerves form the greater, lesser, and lowest splanchnic nerves and supply viscera below the level of the diaphragm, and so are abdominopelvic splanchnic nerves.
thoracic nerves [T1–T12] [TA] twelve nerves on each side, mixed motor and sensory, supplying the muscles and skin of the thoracic and abdominal walls. SYN: nervi thoracici [T1–12].
thoracoabdominal nerves the ventral primary rami of spinal nerves T7–T11 (seventh to eleventh intercostal nerves), which supply the abdominal as well as the thoracic wall; innervate intercostal, subcostal, serratus posterior inferior, transversus abdominis, external and internal oblique, and rectus abdominis muscles, and provide sensory branches to the periphery of the diaphragm, and parietal pleura and peritoneum. SYN: anterior cutaneous nerves of abdomen, pectoral and abdominal anterior cutaneous branch of intercostal nerves, rami cutanei anteriores pectoralis et abdominalis nervorum intercostalium, ramus cutaneus anterior (pectoralis et abdominalis) nervorum thoracicorum.
thoracodorsal n. [TA] arises from the posterior cord of the brachial plexus; it contains fibers from the sixth, seventh, and eighth cervical nerves and supplies the latissimus dorsi muscle. SYN: nervus thoracodorsalis [TA] , long subscapular n..
n. to thyrohyoid muscle SYN: thyrohyoid branch of ansa cervicalis.
tibial n. [TA] one of the two major divisions of the sciatic n., it courses down the back of the leg to terminate as the medial and lateral plantar nerves in the foot; it supplies the hamstring muscles, the muscles of the back of the leg (the dorsiflexors and invertors of the foot), and the plantar aspect of the foot, as well as the skin on the back of the leg and sole of the foot. SYN: nervus tibialis [TA] , medial popliteal n..
tibial communicating n. SYN: medial sural cutaneous n..
Tiedemann n. a sympathetic n. accompanying the central artery of the retina in the optic n..
transverse cervical n. [TA] a branch of the cervical plexus that supplies the skin over the anterior triangle of the neck. SYN: nervus transversus colli [TA] , nervus transversus cervicalis&star, cutaneous cervical n., nervus cervicalis superficialis, superficial cervical n., transverse n. of neck.
transverse n. of neck SYN: transverse cervical n..
trifacial n. SYN: trigeminal n. [CN V].
trigeminal n. [CN V] [TA] the chief sensory n. of the face and the motor n. of the muscles of mastication; its nuclei are in the mesencephalon and in the pons and medulla oblongata extending down into the cervical portion of the spinal cord; it emerges by two roots, sensory and motor, from the lateral portion of the surface of the pons, and enters a cavity of the dura mater, the trigeminal cave, at the apex of the petrous portion of the temporal bone, where the sensory root expands to form the trigeminal ganglion; from there the three divisions (ophthalmic [CN V1], maxillary [CN V2], and mandibular [CN V3] nerves) arise. SYN: nervus trigeminus [CN V] [TA] , fifth cranial n. [CN V], trifacial n..
trochlear n. [CN IV] [TA] supplies the superior oblique muscle of the eye; its origin is in the midbrain below the cerebral aqueduct, and its fibers decussate in the superior medullary velum, and emerge from the brain at the side of the frenulum, the only cranial n. to arise from the dorsal aspect of the brainstem; it therefore has the longest intracranial course, entering the dura in the free edge of the tentorium, close to the posterior clinoid process, and passing in the lateral wall of the cavernous sinus to enter the orbit through the superior orbital fissure. SYN: nervus trochlearis [CN IV] [TA] , fourth cranial n. [CN IV], pathetic n..
twelfth cranial n. [CN XII] SYN: hypoglossal n. [CN XII].
tympanic n. [TA] a n. from the inferior ganglion of the glossopharyngeal n., passing through the tympanic canaliculus to the tympanic cavity, forming there the tympanic plexus that supplies the mucous membrane of the tympanic cavity, mastoid cells, and auditory tube; presynaptic parasympathetic fibers also pass through the tympanic n. via the lesser superficial petrosal n. to the otic ganglion, where they synapse with postsynaptic fibers that continue to supply the parotid gland. SYN: nervus tympanicus [TA] , Andersch n., Jacobson n..
n. of tympanic membrane SYN: branches of auriculotemporal n. to tympanic membrane, under branch.
ulnar n. [TA] arises from the medial cord of the brachial plexus conveying fibers mainly from the C8 and T1 nerves; it passes down the arm, behind the medial epicondyle of the humerus, and down the ulnar side of the anterior compartment of the forearm to the hand; it gives off muscular branches in the forearm to the flexor carpi ulnaris muscle and the ulnar portion of flexor digitorum profundus and supplies the hypothenar, interosseous, medial lumbricals, adductor pollicis, and deep head of flexor hallucis brevis, and the intrinsic muscles of the hand and the skin of the small finger and medial side of the ring finger and adjacent portions of the palm of the hand. The ulnar n. is most vulnerable to injury where it passes subcutaneously behind the medial epicondyle of the humerus. Mild injury here produces “crazy bone” sensation. An ulnar n. lesion here results in loss of flexion of metacarpophalangeal joints and of extension at the interphalangeal joints (“claw hand”). SYN: nervus ulnaris [TA] , cubital n..
unmyelinated n. a n. made up largely, or exclusively, of unmyelinated fibers; a n. composed of axons having no myelin covering, but lying in troughs in Schwann cells; a slow conducting n..
upper lateral cutaneous n. of arm [TA] the terminal branch of the axillary n. supplying the skin over the lower portion of the deltoid and for a distance below its insertion. SYN: nervus cutaneus brachii lateralis superior [TA] , superior lateral brachial cutaneous n.&star.
upper subscapular n. subscapular nerves.
upper thoracic splanchnic nerves SYN: thoracic cardiac branches of thoracic ganglia, under branch.
utricular n. [TA] a branch of the utriculoampullar n., supplying the macula of the utricle. SYN: nervus utricularis [TA] .
utriculoampullar n. [TA] a division of the vestibular part of the eighth cranial n.; it gives off branches to the macula of the utricle (utricular n.) and to the cristae of the ampullae of the anterior and lateral semicircular ducts (anterior and lateral ampullary nerves). SYN: nervus utriculoampullaris [TA] .
vaginal nerves [TA] several nerves passing from the uterovaginal plexus to the vagina. SYN: nervi vaginales [TA] .
vagus n. [CN X] [TA] a mixed n. that arises by numerous small roots from the side of the medulla oblongata, between the glossopharyngeal above and the accessory below; it leaves the cranial cavity by the jugular foramen and passes down to supply the pharynx, larynx, trachea, lungs, heart, and the gastrointestinal tract as far as the left colic (splenic) flexure; the only cranial n. that does not arise from the brain, but is classified as such because it exits from the cranium. SYN: nervus vagus [CN X] [TA] , pneumogastric n., tenth cranial n. [CN X], vagus.
Valentin n. a n. that connects the pterygopalatine ganglion with the abducens n..
vascular nerves [TA] a small n. filament that supplies the wall of a blood vessel. SYN: nervi vascularorum [TA] .
vasomotor n. a motor n. effecting or inhibiting contraction of the blood vessels.
vertebral n. a branch from the stellate ganglion that ascends along the vertebral artery to the level of the axis or atlas, giving branches to the cervical nerves and meninges. SYN: nervus vertebralis.
vestibular n. [TA] the part of the vestibulocochlear n. [CN VIII] peripheral to the vestibular root; it is composed of the central processes of bipolar neurons that have their terminals of their peripheral processes on the hair cells in the ampullae of the semicircular ducts and the maculae of the saccule and utricle, and cell bodies of the vestibular ganglion. SEE ALSO: vestibular root. SYN: nervus vestibularis [TA] , pars vestibularis nervi vestibulocochlearis, superior part of vestibulocochlear n., vestibular part of vestibulocochlear n..
vestibulocochlear n. [CN VIII] [TA] a composite sensory n. innervating the receptor cells of the membranous labyrinth; it consists of two major, anatomically and functionally distinct components, each of which have different central connections: the vestibular n. and the cochlear n.. SYN: nervus vestibulocochlearis [CN VIII] [TA] , eighth cranial n. [CN VIII], eighth n., nervus acusticus, nervus octavus, nervus statoacusticus, octavus, statoacoustic n..
vidian n. SYN: n. of pterygoid canal.
visceral n. a term describing nerves conveying autonomic (general visceral efferent) fibers.
volar interosseous n. SYN: anterior interosseous n..
Wrisberg n. 1. SYN: medial cutaneous n. of arm. 2. SYN: intermediate n..
zygomatic n. [TA] a branch of the maxillary n. [CN V2] in the inferior orbital fissure through which it passes; it gives rise to two sensory branches, the zygomaticotemporal and zygomaticofacial, which supply the skin of the temporal and zygomatic regions and is continued as the communicating branch of the lacrimal n. with the zygomatic n.. SYN: nervus zygomaticus [TA] , orbital n., temporomandibular n..

nerve root sleeve
nerve root sleeve

In myelography, the funnel-shaped extension of the opacified subarachnoid space that surrounds each nerve root as it enters its neural foramen.

nervi
nervi (ner′vi)

Plural of nervus. [L.]

nervimotility
nervimotility (ner-vi-mo-til′i-te)

Capability of movement in response to a nervous stimulus. SYN: neurimotility.

nervimotion
nervimotion (ner-vi-mo′shun)

Movement in response to a nervous stimulus.

nervimotor
nervimotor (ner-vi-mo′ter)

Relating to a motor nerve. SYN: neurimotor.

nervine
nervine (ner′vin)

Acting therapeutically, especially as a sedative, upon the nervous system.

nervone
nervone (ner′von)

A cerebroside containing a nervonyl moiety.

nervonic acid
nervonic acid (ner-von′-ik)

A 24-carbon straight-chain fatty acid unsaturated between C-15 and C-16; occurs in cerebrosides such as nervone.

nervous
nervous (ner′vus)

1. Relating to a nerve or the nerves. 2. Easily excited or agitated; suffering from mental or emotional instability; tense or anxious. 3. Formerly, denoting a temperament characterized by excessive mental and physical alertness, rapid pulse, excitability, often volubility, but not always fixity of purpose. [L. nervosus]

nervous breakdown
nervous breakdown

Nonmedical term for an emotional or mental illness; often a euphemism for a psychiatric disorder.

nervousness
nervousness (ner′vus-nes)

A condition of being nervous (2).

nervus
nervus, gen. and pl. nervi (ner′vus, -vi) [TA]

SYN: nerve. [L.]
n. abducens [CN VI] [TA] SYN: abducent nerve [CN VI].
n. accessorius [CN XI] [TA] SYN: accessory nerve [CN XI].
n. acusticus SYN: vestibulocochlear nerve [CN VIII].
nervi alveolares superiores [TA] SYN: superior alveolar nerves, under nerve.
nervi alveolares superiores anteriores [TA]
n. alveolaris inferior [TA] SYN: inferior alveolar nerve.
n. ampullaris anterior [TA] SYN: anterior ampullary nerve.
n. ampullaris lateralis [TA] SYN: lateral ampullar nerve.
n. ampullaris posterior [TA] SYN: posterior ampullar nerve.
nervi anales inferiores [TA] SYN: inferior anal nerves, under nerve.
n. anococcygeus SYN: anococcygeal nerve.
n. antebrachii anterior SYN: anterior interosseous nerve.
n. antebrachii posterior SYN: posterior interosseous nerve.
n. articularis SYN: articular nerve.
nervi auriculares anteriores [TA] SYN: anterior auricular nerves, under nerve.
n. auricularis magnus [TA] SYN: great auricular nerve.
n. auricularis posterior [TA] SYN: posterior auricular nerve.
n. auriculotemporalis [TA] SYN: auriculotemporal nerve.
n. autonomicus [TA] SYN: autonomic nerve.
n. axillaris [TA] SYN: axillary nerve.
n. buccalis [TA] SYN: buccal nerve.
n. canalis pterygoidei [TA] SYN: nerve of pterygoid canal.
nervi cardiaci thoracici SYN: thoracic cardiac branches of thoracic ganglia, under branch.
n. cardiacus cervicalis inferior [TA] SYN: inferior cervical cardiac nerve.
n. cardiacus cervicalis medius [TA] SYN: middle cervical cardiac nerve.
n. cardiacus cervicalis superior [TA] SYN: superior cervical cardiac nerve.
nervi carotici externi [TA] SYN: external carotid nerves, under nerve.
nervi caroticotympanicus SYN: caroticotympanic nerves, under nerve.
n. caroticus internus [TA] SYN: internal carotid nerve.
nervi cavernosi clitoridis [TA] SYN: cavernous nerves of clitoris, under nerve.
nervi cavernosi penis [TA] SYN: cavernous nerves of penis, under nerve.
nervi cervicales [C1–C8] SYN: cervical nerves [C1–C8], under nerve.
n. cervicalis superficialis SYN: transverse cervical nerve.
n. ciliaris brevis, pl .nervi ciliares breves [TA] SYN: short ciliary nerve.
n. ciliaris longus, pl .nervi ciliares longi [TA] SYN: long ciliary nerve.
nervi clunium inferiores [TA] SYN: inferior clunial nerves, under nerve.
nervi clunium medii [TA] SYN: medial clunial nerves, under nerve.
nervi clunium superiores [TA] SYN: superior clunial nerves, under nerve.
n. coccygeus [Co] [TA] SYN: coccygeal nerve [Co].
n. cochlearis [TA] SYN: cochlear nerve. SEE ALSO: cochlear root of VIII nerve.
n. communicans fibularis SYN: sural communicating branch of common fibular nerve.
n. communicans peroneus SYN: sural communicating branch of common fibular nerve.
nervi craniales [TA] SYN: cranial nerves, under nerve.
n. cutaneus [TA] SYN: cutaneous nerve.
n. cutaneus antebrachii lateralis [TA] SYN: lateral cutaneous nerve of forearm.
n. cutaneus antebrachii medialis [TA] SYN: medial cutaneous nerve of forearm.
n. cutaneus antebrachii posterior [TA] SYN: posterior cutaneous nerve of forearm.
n. cutaneus brachii lateralis inferior [TA] SYN: inferior lateral cutaneous nerve of arm.
n. cutaneus brachii lateralis superior [TA] SYN: upper lateral cutaneous nerve of arm.
n. cutaneus brachii medialis [TA] SYN: medial cutaneous nerve of arm.
n. cutaneus brachii posterior [TA] SYN: posterior cutaneous nerve of arm.
n. cutaneus dorsalis intermedius [TA] SYN: intermediate dorsal cutaneous nerve.
n. cutaneus dorsalis lateralis [TA] SYN: lateral dorsal cutaneous nerve.
n. cutaneus dorsalis medialis [TA] SYN: medial dorsal cutaneous nerve.
n. cutaneus femoris lateralis [TA] SYN: lateral cutaneous nerve of thigh.
n. cutaneus femoris posterior [TA] SYN: posterior cutaneous nerve of thigh.
n. cutaneus surae lateralis [TA] SYN: lateral sural cutaneous nerve.
n. cutaneus surae medialis [TA] SYN: medial sural cutaneous nerve.
nervi digitales dorsales SYN: dorsal digital nerves of hand, under nerve.
nervi digitales dorsales nervi fibularis profundi [TA] SYN: dorsal digital nerves of deep fibular nerve, under nerve.
nervi digitales dorsales nervi fibularis superficialis [TA] SYN: dorsal digital nerves of superficial fibular nerve, under nerve.
nervi digitales dorsales nervi ulnaris [TA] SYN: dorsal digital nerves of ulnar nerve, under nerve.
nervi digitales dorsales pedis [TA] SYN: dorsal digital nerves of foot, under nerve.
nervi digitales palmares communes [TA] SYN: common palmar digital nerves, under nerve.
nervi digitales palmares proprii [TA] SYN: proper palmar digital nerves, under nerve.
nervi digitales plantares communes [TA] SYN: common plantar digital nerves, under nerve.
nervi digitales plantares proprii [TA] SYN: proper plantar digital nerves, under nerve.
n. dorsalis clitoridis [TA] SYN: dorsal nerve of clitoris.
n. dorsalis penis [TA] SYN: dorsal nerve of penis.
n. dorsalis scapulae [TA] SYN: dorsal scapular nerve.
nervi erigentes SYN: pelvic splanchnic nerves, under nerve.
n. ethmoidalis anterior [TA] SYN: anterior ethmoidal nerve.
n. ethmoidalis posterior [TA] SYN: posterior ethmoidal nerve.
n. facialis [CN VII] [TA] SYN: facial nerve [CN VII].
n. femoralis [TA] SYN: femoral nerve.
n. fibularis communis [TA] SYN: common fibular nerve.
n. fibularis profundus [TA] SYN: deep fibular nerve.
n. fibularis superficialis [TA] SYN: superficial fibular nerve.
n. frontalis [TA] SYN: frontal nerve.
n. furcalis SYN: fourth lumbar nerve [L4].
n. genitofemoralis [TA] SYN: genitofemoral nerve.
n. glossopharyngeus [CN IX] [TA] SYN: glossopharyngeal nerve [CN IX].
n. gluteus inferior [TA] SYN: inferior gluteal nerve.
n. gluteus superior [TA] SYN: superior gluteal nerve.
n. hemorrhoidalis superior rectal (nervous) plexus, inferior anal nerves, under nerve.
n. hypogastricus [TA] SYN: hypogastric nerve.
n. hypoglossus [CN XII] [TA] SYN: hypoglossal nerve [CN XII].
n. iliohypogastricus [TA] SYN: iliohypogastric nerve.
n. ilioinguinalis [TA] SYN: ilioinguinal nerve.
n. impar SYN: terminal filum.
n. infraorbitalis [TA] SYN: infraorbital nerve.
n. infratrochlearis [TA] SYN: infratrochlear nerve.
nervi intercostales [TA] SYN: intercostal nerves, under nerve.
nervi intercostobrachiales [TA] SYN: intercostobrachial nerves, under nerve.
n. intermedius [TA] SYN: intermediate nerve.
n. interosseus antebrachii anterior [TA] SYN: anterior interosseous nerve.
n. interosseus antebrachii posterior [TA] SYN: posterior interosseous nerve.
n. interosseus cruris [TA] SYN: crural interosseous nerve.
n. interosseus dorsalis SYN: posterior interosseous nerve.
n. interosseus posterior SYN: posterior interosseous nerve.
n. ischiadicus [TA] SYN: sciatic nerve.
n. jugularis [TA] SYN: jugular nerve.
nervi labiales anteriores [TA] SYN: anterior labial nerves, under nerve.
nervi labiales posteriores [TA] SYN: posterior labial nerves, under nerve.
n. lacrimalis [TA] SYN: lacrimal nerve.
n. laryngeus inferior [TA] SYN: inferior laryngeal nerve.
n. laryngeus recurrens [TA] SYN: recurrent laryngeal nerve.
n. laryngeus superior [TA] SYN: superior laryngeal nerve.
n. lingualis [TA] SYN: lingual nerve.
nervi lumbales SYN: lumbar nerves [L1–L5], under nerve.
n. mandibularis [CN V3] [TA] SYN: mandibular nerve [CN V3].
n. massetericus [TA] SYN: masseteric nerve.
n. maxillaris [CN V2] [TA] SYN: maxillary nerve [CN V2].
n. meatus acustici externi [TA] SYN: nerve to external acoustic meatus.
n. medianus [TA] SYN: median nerve.
n. mentalis [TA] SYN: mental nerve.
n. mixtus [TA] SYN: mixed nerve.
n. musculi tensoris tympani [TA] SYN: nerve to tensor tympani (muscle).
n. musculi tensoris veli palatini [TA] SYN: nerve to tensor veli palatini (muscle).
n. musculocutaneus [TA] SYN: musculocutaneous nerve.
n. mylohyoideus [TA] SYN: nerve to mylohyoid.
n. nasociliaris [TA] SYN: nasociliary nerve.
n. nasopalatinus [TA] SYN: nasopalatine nerve.
nervi nervorum nerves distributed to the sheaths of nerve trunks.
n. obturatorius [TA] SYN: obturator nerve.
n. occipitalis major [TA] SYN: greater occipital nerve.
n. occipitalis minor [TA] SYN: lesser occipital nerve.
n. occipitalis tertius [TA] SYN: third occipital nerve.
n. octavus SYN: vestibulocochlear nerve [CN VIII].
n. oculomotorius [CN III] [TA] SYN: oculomotor nerve [CN III].
n. olfactorii [CN I] [TA] SYN: olfactory nerves [CN I], under nerve. SEE ALSO: olfactory tract.
n. ophthalmicus [CN V1] [TA] SYN: ophthalmic nerve [CN V1].
n. opticus [CN II] [TA] SYN: optic nerve [CN II].
nervi palatini minores [TA] SYN: lesser palatine nerves, under nerve.
n. palatinus major [TA] SYN: greater palatine nerve.
n. pectoralis lateralis [TA] SYN: lateral pectoral nerve.
n. pectoralis medialis [TA] SYN: medial pectoral nerve.
nervi pelvici splanchnici [TA] SYN: pelvic splanchnic nerves, under nerve.
nervi perineales [TA] SYN: perineal nerves, under nerve.
n. peroneus communis common fibular nerve.
n. peroneus profundus deep fibular nerve.
n. peroneus superficialis superficial fibular nerve.
n. petrosus major [TA] SYN: greater petrosal nerve.
n. petrosus minor [TA] SYN: lesser petrosal nerve.
n. petrosus profundus [TA] SYN: deep petrosal nerve.
n. pharyngeus [TA] SYN: pharyngeal nerve.
nervi phrenici accessorii [TA] SYN: accessory phrenic nerves, under nerve.
n. phrenicus [TA] SYN: phrenic nerve.
n. plantaris lateralis [TA] SYN: lateral plantar nerve.
n. plantaris medialis [TA] SYN: medial plantar nerve.
n. presacralis superior hypogastric (nervous) plexus.
n. pterygoideus [TA] SYN: pterygoid nerve.
nervi pterygopalatini SYN: sensory root of pterygopalatine ganglion.
n. pudendus [TA] SYN: pudendal nerve.
n. radialis [TA] SYN: radial nerve.
nervi rectales inferiores inferior anal nerves, under nerve.
n. saccularis [TA] SYN: saccular nerve.
nervi sacrales [S1–S5] SYN: sacral nerves [S1–S5], under nerve.
n. saphenus [TA] SYN: saphenous nerve.
n. sciaticus SYN: sciatic nerve.
nervi scrotales anteriores [TA] SYN: anterior scrotal nerves, under nerve.
nervi scrotales posteriores [TA] SYN: posterior scrotal nerves, under nerve.
n. spermaticus externus SYN: genital branch of genitofemoral nerve.
nervi sphenopalatini SYN: sensory root of pterygopalatine ganglion.
nervi spinales [TA] SYN: spinal nerves, under nerve.
n. spinosus meningeal branch of mandibular nerve.
nervi splanchnici lumbales [TA] SYN: lumbar splanchnic nerves, under nerve.
nervi splanchnici sacrales [TA] SYN: sacral splanchnic nerves, under nerve.
n. splanchnicus imus [TA] SYN: least splanchnic nerve.
n. splanchnicus major [TA] SYN: greater splanchnic nerve.
n. splanchnicus minor [TA] SYN: lesser splanchnic nerve.
n. stapedius [TA] SYN: nerve to stapedius muscle.
n. statoacusticus SYN: vestibulocochlear nerve [CN VIII].
n. subclavius [TA] SYN: subclavian nerve.
n. subcostalis [TA] SYN: subcostal nerve.
n. sublingualis [TA] SYN: sublingual nerve.
n. suboccipitalis [TA] SYN: suboccipital nerve.
nervi subscapulares [TA] SYN: subscapular nerves, under nerve.
n. supraclavicularis intermedius [TA] SYN: intermediate supraclavicular nerve.
n. supraclavicularis lateralis [TA] SYN: lateral supraclavicular nerve.
n. supraclavicularis medialis [TA] SYN: medial supraclavicular nerve.
n. supraorbitalis [TA] SYN: supraorbital nerve.
n. suprascapularis [TA] SYN: suprascapular nerve.
n. supratrochlearis [TA] SYN: supratrochlear nerve.
n. suralis [TA] SYN: sural nerve.
nervi temporales profundi [TA] SYN: deep temporal nerves, under nerve.
n. tentorii SYN: tentorial nerve.
n. terminalis [TA] SYN: terminal nerve.
nervi thoracici [T1–12] SYN: thoracic nerves [T1–T12], under nerve.
n. thoracicus longus [TA] SYN: long thoracic nerve.
n. thoracodorsalis [TA] SYN: thoracodorsal nerve.
n. tibialis [TA] SYN: tibial nerve.
n. transversus cervicalis transverse cervical nerve.
n. transversus colli [TA] SYN: transverse cervical nerve.
n. trigeminus [CN V] [TA] SYN: trigeminal nerve [CN V].
n. trochlearis [CN IV] [TA] SYN: trochlear nerve [CN IV].
n. tympanicus [TA] SYN: tympanic nerve.
n. ulnaris [TA] SYN: ulnar nerve.
n. utricularis [TA] SYN: utricular nerve.
n. utriculoampullaris [TA] SYN: utriculoampullar nerve.
nervi vaginales [TA] SYN: vaginal nerves, under nerve.
n. vagus [CN X] [TA] SYN: vagus nerve [CN X].
nervi vascularorum [TA] SYN: vascular nerves, under nerve.
n. vertebralis SYN: vertebral nerve.
n. vestibularis [TA] SYN: vestibular nerve. SEE ALSO: vestibular root of vestibulocochlear nerve.
n. vestibulocochlearis [CN VIII] [TA] SYN: vestibulocochlear nerve [CN VIII]. See entries under radix.
n. zygomaticus [TA] SYN: zygomatic nerve.

nesidiectomy
nesidiectomy (ne-sid′e-ek′to-me)

Excision of islet tissue of the pancreas. [G. nesidion, islet, dim. of nesos, island, + ektome, excision]

nesidioblast
nesidioblast (ne-sid′e-o-blast)

A pancreatic islet-forming cell. [G. nesidion, dim. of nesos, island, + blastos, germ]

nesidioblastosis
nesidioblastosis (ne-sid′e-o-blas-to′sis)

Hyperplasia of the cells of the islets of Langerhans. [nesidioblast + G. -osis, tumor]

Nessler
Nessler

A., German chemist, 1827–1905. See N. reagent.

nesslerize
nesslerize (nes′ler-iz)

To treat with Nessler reagent; used in the determination of urea nitrogen in the blood and in the urine.

nest
nest

A group or collection of similar objects. SEE ALSO: nidus. [A.S.]
Brunn n. glandlike invagination of surface transitional epithelium in the epithelium of the lower urinary tract.
cell n. a small focus or accumulation of one type of cell that is different from the other cells in the tissue.
epithelial n. SYN: keratin pearl.
isogenous n. a clone of cartilage cells all from one progenitor cell and occurring as a cluster.

net
net

SYN: network (1) .
Chiari n. abnormal fibrous or lacelike strands in the right atrium, extending from the margins of the coronary or caval valves and attaching to the atrial wall along the line of the crista terminalis; results when resorption of the septum spurium is markedly less than normal.
chromidial n. a reticulum of basophilic-staining material in the cytoplasm of certain cells.

Netherton
Netherton

Earl W., 20th century U.S. dermatologist. See N. syndrome.

netilmicin sulfate
netilmicin sulfate (net-il-mi′sin)

A parenteral aminoglycoside antibiotic used for short-term treatment of serious or life-threatening bacterial infections.

nettle
nettle (net′l)

SYN: urtica. [A.S. netele]

network
network (net′werk)

1. A structure bearing a resemblance to a woven fabric. A n. of nerve fibers or small vessels. SYN: net, rete (1) . SEE ALSO: reticulum. 2. The persons in a patient's environment, especially as significant for the course of the illness.
acromial arterial n. SYN: acromial anastomosis of the thoracoacromial artery.
arteriolar n. SYN: arterial plexus.
articular n. SYN: articular vascular plexus. See plane joint.
articular vascular n. SYN: articular vascular plexus.
articular vascular n. of elbow SYN: cubital anastomosis.
articular vascular n. of knee SYN: genicular anastomosis.
calcaneal arterial n. SYN: calcaneal anastomosis.
chromatin n. the appearance of basophilic material in the nuclei of many cells after fixation. SEE ALSO: chromatin.
dorsal carpal n. SYN: dorsal carpal arterial arch.
dorsal venous n. of foot [TA] a superficial n. of fine veins on the dorsum of the foot. SYN: rete venosum dorsale pedis [TA] .
dorsal venous n. of hand [TA] a superficial n. of veins on the dorsum of the hand emptying into the cephalic and the basilic veins. SYN: rete venosum dorsale manus [TA] .
lateral malleolar n. [TA] a n. over the lateral malleolus formed by branches of the posterior lateral malleolar, anterior lateral malleolar, peroneal, and lateral tarsal arteries. SYN: rete malleolare laterale [TA] .
linin n. linin (3) .
medial malleolar n. [TA] a n. over the medial malleolus formed by branches from the anterior and posterior medial malleolar and medial tarsal arteries. SYN: rete malleolare mediale [TA] .
neurofibrillar n. the intertwined patterns formed by neurofibrils in the neuron.
patellar n. SYN: patellar anastomosis.
peritarsal n. the lymphatic vessels along the margin of the eyelid.
plantar venous n. [TA] a fine superficial venous n. in the sole of the foot. SYN: rete venosum plantare [TA] .
Purkinje n. the n. formed by Purkinje fibers beneath the endocardium.
subpapillary n. the capillary blood vessels in the deeper layers of the skin.
trabecular n. SYN: trabecular tissue of sclera.

NeuAc
NeuAc

Abbreviation for N-acetylneuraminic acid.

Neubauer
Neubauer

Johann E., German anatomist, 1742–1777. See N. artery.

Neufeld
Neufeld

Fred, German bacteriologist, 1869–1945. See N. reaction, N. capsular swelling.

Neumann
Neumann

Ernst F.C., German histologist, anatomist, and pathologist, 1834–1918. See N. sheath, Rouget-N. sheath.

Neumann
Neumann

Franz E., German physicist, 1798–1895. See N. law.

Neumann
Neumann

Isidor Edler von Heilwart, Austrian dermatologist, 1832–1906. See N. disease.

neur- neur-, neuri-, neuro-

Nerve, nerve tissue, the nervous system. [G. neuron]

neural
neural (noor′al)

1. Relating to any structure composed of nerve cells or their processes, or that on further development will evolve into nerve cells. 2. Referring to the dorsal side of the vertebral bodies or their precursors, where the spinal cord is located, as opposed to hemal (2). [G. neuron, nerve]

neuralgia
neuralgia (noo-ral′je-a)

Pain of a severe, throbbing, or stabbing character in the course or distribution of a nerve. SYN: neurodynia. [neur- + G. algos, pain]
atypical facial n. SYN: atypical trigeminal n..
atypical trigeminal n. periodic pain in any region of the face, teeth, tongue, and occasionally in the occipital or shoulder area, which lasts several minutes to several days but has no trigger point and lacks the paroxysmal character of tic douloureux. SYN: atypical facial n..
epileptiform n. SYN: trigeminal n..
facial n. SYN: trigeminal n..
n. facialis vera SYN: geniculate n..
Fothergill n. SYN: trigeminal n..
geniculate n. a severe paroxysmal lancinating pain deep in the ear, on the anterior wall of the external meatus, and on a small area just in front of the pinna. SYN: geniculate otalgia, Hunt n., n. facialis vera.
glossopharyngeal n. paroxysmal lancinating pain in the throat or palate. SYN: glossopharyngeal tic.
hallucinatory n. an impression of local pain persisting after an attack of n. has ceased.
Hunt n. SYN: geniculate n..
idiopathic n. nerve pain not due to any apparent cause.
intercostal n. pain in the chest wall due to n. of one or more of the intercostal nerves.
mammary n. n. of the intercostal nerve or nerves supplying the breast.
Morton n. n. of an interdigital nerve, usually the anastomotic branch between the medial and lateral plantar nerves, resulting from compression of the nerve by the metatarsophalangeal joint. SYN: Morton metatarsalgia, Morton neuroma.
occipital n. posttraumatic neck syndrome.
periodic migrainous n. recurrent facial pain and headache, more common in men than in women. SYN: Harris migraine.
sciatic n. SYN: sciatica.
Sluder n. SYN: sphenopalatine n..
sphenopalatine n. n. of the lower half of the face, with pain referred to the root of the nose, upper teeth, eyes, ears, mastoid, and occiput, in association with nasal congestion and rhinorrhea occurring in infection of the nasal sinuses, and produced by lesions of the sphenopalatine ganglion; ocular hyperemia and excessive lacrimation may occur. SYN: Sluder n..
stump n. pain experienced as coming from an absent part, caused by irritation of neuromas in the scarred tissue of an amputation stump.
suboccipital n. posttraumatic neck syndrome.
supraorbital n. n. of the supraorbital nerve.
symptomatic n. n. occurring as a symptom of some local or systemic disease not involving primarily nerve structures.
trifacial n. SYN: trigeminal n..
trigeminal n. severe, paroxysmal bursts of pain in one or more branches of the trigeminal nerve; often induced by touching trigger points in or about the mouth. SYN: epileptiform n., facial n., Fothergill disease (1) , Fothergill n., tic douloureux, trifacial n..

neuralgic
neuralgic (noo-ral′jik)

Relating to, resembling, or of the character of, neuralgia.

neuralgiform
neuralgiform (noo-ral′ji-form)

Resembling or of the character of neuralgia.

neuramebimeter
neuramebimeter (noor′am-e-bim′e-ter)

An instrument for measuring the rapidity of response of a nerve to any stimulus. [neur- + G. amoibe, exchange, return, answer, + metron, measure]

neuraminic acid
neuraminic acid (noor′a-min′ik)

An aldol product of d-mannosamine and pyruvic acid, linking the C-1 of the former to the C-3 of the latter. The N- and O-acyl derivatives of n. are known as sialic acids and are constituents of gangliosides and of the polysaccharide components of muco- and glycoproteins from many tissues, secretions, and species. SYN: prehemataminic acid.

neuraminidase
neuraminidase (noor-a-min′i-das)

SYN: sialidase.

neuranagenesis
neuranagenesis (noor′an-a-jen′e-sis)

Regeneration of a nerve. [neur- + G. ana, up, again, + genesis, origin]

neurapophysis
neurapophysis (noor-a-pof′i-sis)

SYN: lamina of vertebral arch. [neur- + G. apophysis, offshoot]

neurapraxia
neurapraxia (noor-a-prak′se-a)

The mildest type of focal nerve lesion that produces clinical deficits; localized loss of conduction along a nerve without axon degeneration; caused by a focal lesion, usually demyelinating, and followed by a complete recovery. Term is often misspelled (neuropraxia), and often used, incorrectly, as a synonym for nerve lesion. SEE ALSO: axonotmesis. [neur- + G. a- priv. + praxis, action]

neurarchy
neurarchy (noor′ar-ke)

The dominant action of the nervous system over the physical processes of the body. [neur- + G. arche, dominion]

neurasthenia
neurasthenia (noor-as-the′ne-a)

An ill-defined condition, commonly accompanying or following depression, characterized by vague fatigue believed to be brought on by psychological factors. [neur- + G. astheneia, weakness]
angiopathic n., angioparalytic n. an obsolete term for a form of mild n. in which the chief complaint is of a universal throbbing or sense of pulsation throughout the body.
gastric n. a condition marked by vague epigastric atony and distention, and mild neurasthenic symptoms.
n. gravis obsolete term for a condition of extreme and lasting n..
n. praecox obsolete term for a form of nervous exhaustion appearing in the adolescent period.
primary n. obsolete term for n. praecox.
pulsating n. obsolete term for angiopathic n..
sexual n. obsolete term for a form in which sexual erethism, weakness, or perversion is a marked symptom.
traumatic n. obsolete term for posttraumatic syndrome.

neurasthenic
neurasthenic (noor-as-then′ik)

Relating to, or suffering from, neurasthenia.

neuraxis
neuraxis (noo-rak′sis)

The axial, unpaired part of the central nervous system: spinal cord, rhombencephalon, mesencephalon, and diencephalon, in contrast to the paired cerebral hemisphere, or telencephalon.

neuraxon
neuraxon, neuraxone (noo-rak′son, -son)

Obsolete term for axon. [neur- + G. axon, axis]

neurectasis
neurectasis, neurectasia, neurectasy (noo-rek′ta-sis, noor-ek-ta′ze-a, -ek′ta-se)

The operation of stretching a nerve or nerve trunk. SYN: neurotension. [neur- + G. ektasis, extension]

neurectomy
neurectomy (noo-rek′to-me)

Excision of a segment of a nerve. SYN: neuroectomy. [neur- + G. ektome, excision]
occipital n. excision of greater occipital nerve for the treatment of occipital neuralgia.
presacral n. cutting of the presacral nerve to relieve severe dysmenorrhea. SYN: Cotte operation, presacral sympathectomy.
retrogasserian n. SYN: trigeminal rhizotomy.
vestibular n. transection of the vestibular division of the eighth cranial nerve.

neurectopia
neurectopia, neurectopy (noor-ek-to′pe-a, -ek′to-pe)

A condition in which a nerve follows an anomalous course. [neur- + G. ektopos, fr. ek, out of, + topos, place]

neurepithelium
neurepithelium (noor′ep-i-the′le-um)

SYN: neuroepithelium.

neuri- neuri-

See neur-.

neuridine
neuridine (noor′i-den)

SYN: spermine.

neurilemma
neurilemma (noor-i-lem′a)

A cell that enfolds one or more axons of the peripheral nervous system; in myelinated fibers its plasma membrane forms the lamellae of myelin. SYN: neurolemma, sheath of Schwann. [neuri + G. lemma, husk]

neurilemoma
neurilemoma (noor′i-le-mo′ma)

SYN: schwannoma. [neurilemma + G. -oma, tumor]
acoustic n. schwannoma arising from cranial nerve VIII.
Antoni type A n. relatively solid or compact arrangement of neoplastic tissue that consists of Schwann cells arranged in twisting bundles and associated with delicate reticulin fibers; the nuclei of the Schwann cells are frequently grouped in parallel rows (so-called palisades), and the nuclei and fibers sometimes form exaggerated tactile corpuscles, called Verocay bodies.
Antoni type B n. relatively soft or loose arrangement of neoplastic tissue that consists of Schwann cells in a haphazard or nondescript type of arrangement among reticulin fibers and tiny cystlike foci; fat-laden macrophages may be observed in some of the larger neoplasms.

neurility
neurility (noo-ril′i-te)

The property, inherent in nerves, of conducting stimuli.

neurimotility
neurimotility (noor′i-mo-til′i-te)

SYN: nervimotility.

neurimotor
neurimotor (noor-i-mo′ter)

SYN: nervimotor.

neurine
neurine (noor′en)

A toxic amine that is a product of decomposing animal matter (dehydration of choline) and a poisonous constituent of mushrooms.

neurinoma
neurinoma (noor-i-no′ma)

Obsolete term for schwannoma.
acoustic n. SYN: vestibular schwannoma.

neuritic
neuritic (noo-rit′ik)

Relating to neuritis.

neuritis
neuritis, pl .neuritides (noo-ri′tis, noo-rit′i-dez)

1. Inflammation of a nerve. 2. SYN: neuropathy. [neuri- + G. -itis, inflammation]
adventitial n. inflammation of the sheath of a nerve. SEE ALSO: perineuritis.
ascending n. inflammation progressing upward along a nerve trunk in a direction away from the periphery.
axial n. SYN: parenchymatous n..
brachial n. SYN: neuralgic amyotrophy.
central n. SYN: parenchymatous n..
descending n. inflammation progressing along a nerve trunk toward the periphery.
Eichhorst n. SYN: interstitial n..
endemic n. SYN: beriberi.
fallopian n. SYN: facial paralysis.
interstitial n. inflammation of the connective tissue framework of a nerve. SYN: Eichhorst n..
intraocular n. inflammation of the retinal portion of the optic nerve.
Leyden n. fatty degeneration of the fibers of the affected nerve.
multiple n. SYN: polyneuropathy.
occipital n. posttraumatic neck syndrome.
optic n. inflammation of the optic nerve. SEE ALSO: neuromyelitis optica, retrobulbar n., papillitis.
parenchymatous n. inflammation of the nervous substance proper, the axons, and myelin. SYN: axial n., central n..
retrobulbar n. optic n. without swelling of the optic disk.
sciatic n. SYN: sciatica.
segmental n. 1. inflammation occurring at several points along the course of a nerve; 2. segmental demyelinating neuropathy
suboccipital n. posttraumatic neck syndrome.
toxic n. n. caused by an endogenous or exogenous toxin.
traumatic n. nerve lesion following an injury.

neuro- neuro-

See neur-.

neuroallergy
neuroallergy (noor-o-al′er-je)

An allergic reaction in nervous tissue.

neuroanastomosis
neuroanastomosis (noor′o-an-as-to-mo′sis)

Surgical formation of a junction between nerves.

neuroanatomy
neuroanatomy (noor′o-a-nat′o-me)

The anatomy of the nervous system, usually specific to the central nervous system.

neuroarthropathy
neuroarthropathy (noor′o-ar-throp′a-the)

A joint disorder caused by loss of joint sensation. See Charcot joint. [neuro- + G. arthron, joint, + pathos, suffering, disease]

neuroaugmentation
neuroaugmentation (noor′o-awg-men-ta′shoon)

Use of electrical stimulation to supplement activity of the nervous system.

neuroaugmentive
neuroaugmentive (noor′o-awg-men′tiv)

Related to neuroaugmentation.

neurobiology
neurobiology

The biology of the nervous system.

neurobiotaxis
neurobiotaxis

The theory that nerve cell bodies may move toward, or their axons may grow toward, the area from which they receive the most stimuli. [G. neuron, nerve + bios, life + taxis, arrangement]

neuroblast
neuroblast (noor′o-blast)

An embryonic nerve cell. [neuro- + G. blastos, germ]

neuroblastoma
neuroblastoma (noor′o-blas-to′ma)

A malignant neoplasm characterized by immature, only slightly differentiated nerve cells of embryonic type, i.e., neuroblasts; typical cells are relatively small (10–15 μm in diameter) with disproportionately large, darkly staining, vesicular nuclei and scant, palely acidophilic cytoplasm; they may be arranged in sheets, irregular clumps, or cordlike groups, as well as occurring individually and in pseudorosettes (with nuclei arranged peripherally about the centrally directed cytoplasmic processes); ordinarily, the stroma is sparse, and foci of necrosis and hemorrhage are not unusual. Neuroblastomas occur frequently in infants and children in the mediastinal and retroperitoneal regions (approximately 30% associated with the adrenal glands); widespread metastases to the liver, lungs, lymph nodes, cranial cavity, and skeleton are very common.
olfactory n. a rare, often slowly growing malignant tumor of primitive nerve cells, usually arising in the olfactory area of the nasal cavity. SYN: olfactory esthesioneuroblastoma.

neuroborreliosis
neuroborreliosis (noor′o-bor-rel′e-o′sis)

Inflammation or disease caused by infection of the central nervous system by a member of the genus Borrelia. It is frequently a late stage in the disease process, particularly in immunosuppressed individuals, such as those suffering from AIDS.

neurocardiac
neurocardiac (noor-o-kar′de-ak)

1. Relating to the nerve supply of the heart. 2. Relating to a cardiac neurosis. [neuro- + G. kardia, heart]

neurocele
neurocele (noor′o-sel)

Rarely used collective term for the central cavity of the cerebrospinal axis; the combined ventricles of the brain and central canal of the spinal cord. [neuro- + G. koilos, hollow]

neurochemistry
neurochemistry (noor-o-kem′is-tre)

The science concerned with the chemical aspects of nervous system structure and function.

neurochitin
neurochitin (noor-o-ki′tin)

SYN: neurokeratin. [neuro- + G. chiton, tunic]

neurochorioretinitis
neurochorioretinitis (noor-o-kor′e-o-ret-in-i′tis)

Inflammation of the choroid, the retina, and the optic nerve.

neurochoroiditis
neurochoroiditis (noor′o-ko-roy-di′tis)

Inflammation of the choroid and the optic nerve.

neurocladism
neurocladism (noo-rok′la-dizm)

The outgrowth of axons from the central stump to bridge the gap in a cut nerve. SYN: odogenesis. [neuro- + G. klados, a young branch]

neurocranium
neurocranium (noor-o-kra′ne-um) [TA]

Those bones of the skull enclosing the brain, as distinguished from the bones of the face. SYN: brain box&star, braincase, cranial vault, cranium cerebrale, cerebral cranium. [neuro- + G. kranion, skull]
cartilaginous n. in the embryo, that part of the base of the skull first laid down in cartilage and then ossified.
membranous n. the vault of the embryonic skull that is ossified in membrane.

neurocristopathy
neurocristopathy (noor′o-kris-top′a-the)

Developmental anomaly arising from maldevelopment of neural crest cells. [neuro- + L. crista, crest, + G. pathos, suffering]

neurocyte
neurocyte (noor′o-sit)

SYN: neuron. [neuro- + G. kytos, cell]

neurocytolysis
neurocytolysis (noor′o-si-tol′i-sis)

Destruction of neurons. [neuro- + G. kytos, cell, + lysis, dissolution]

neurocytoma
neurocytoma (noor′o-si-to′ma)

A tumor of neuronal differentiation usually intraventricular in location, consisting of sheets of cells with uniform nuclei and occasional perivascular pseudorosette formation. [neuro- + G. kytos, cell, + -oma, tumor]

neurodendrite
neurodendrite (noor-o-den′drit)

SYN: dendrite (1) .

neurodendron
neurodendron (noor-o-den′dron)

SYN: dendrite (1) .

neurodermatitis
neurodermatitis (noor′o-der-ma-ti′tis)

A chronic lichenified skin lesion, localized or disseminated. [neuro- + G. derma, skin, + -itis, inflammation]

neurodynamic
neurodynamic (noor′o-di-nam′ik)

Pertaining to nervous energy. [neuro- + G. dynamis, force]

neurodynia
neurodynia (noor-o-din′e-a)

SYN: neuralgia. [neuro- + G. odyne, pain]

neuroectoderm
neuroectoderm (noor-o-ek′to-derm)

That central region of the early embryonic ectoderm that on further development forms the brain and spinal cord, and the neural crest cells that become the nerve cells and neurilemma or Schwann cells of the peripheral nervous system.

neuroectodermal
neuroectodermal (noor′o-ek-to-der′mal)

Relating to the neuroectoderm.

neuroectomy
neuroectomy (noor-o-ek′to-me)

SYN: neurectomy.

neuroencephalomyelopathy
neuroencephalomyelopathy (noor′o-en-sef′a-lo-mi-e-lop′a-the)

Disease of the brain, spinal cord, and nerves.

neuroendocrine
neuroendocrine (noor-o-en′do-krin)

1. Pertaining to the anatomic and functional relationships between the nervous system and the endocrine apparatus. 2. Descriptive of cells that release a hormone into the circulating blood in response to a neural stimulus. Such cells may compose a peripheral endocrine gland ( e.g., the insulin-secreting beta cells of the islets of Langerhans in the pancreas and the adrenaline-secreting chromaffin cells of the adrenal medulla); others are neurons in the brain ( e.g., the neurons of the supraoptic nucleus that release antidiuretic hormone from their axon terminals in the posterior lobe of the hypophysis).

neuroendocrinology
neuroendocrinology (noor-o-en′do-krin-ol′o-je)

The specialty concerned with the anatomic and functional relationships between the nervous system and the endocrine apparatus.

neuroepithelial
neuroepithelial (noor′o-ep-i-the′le-al)

Relating to the neuroepithelium.

neuroepithelium
neuroepithelium (noor′o-ep-i-the′le-oom)

Epithelial cells specialized for the reception of external stimuli. Most neuroepithelial cells, notably the hair cells of the inner ear and the receptor cells of the taste buds, are not true neurons but transducer cells that stand in synaptic contact with the peripheral endings of sensory ganglion cells. The neuroepithelial receptor cells of the olfactory epithelium, by contrast, are true peripheral neurons whose extremely thin, unmyelinated axons compose the olfactory filaments that enter the olfactory bulb of the cerebral hemisphere. The NA also applies the term to the rods and cones of the retina. SYN: neurepithelium, neuroepithelial cells.
n. of ampullary crest the specialized sensory hair cells in the ampullary crest of the ampulla of each semicircular duct.
n. of macula the specialized sensory hair cells of the epithelium of the macula sacculi and macula utriculi. SEE ALSO: macula.

neurofibra neurofibra

neurofibrae autonomicae [TA] SYN: autonomic nerve fibers, under fiber.
neurofibrae postganglionicae SYN: postganglionic.
neurofibrae preganglionicae SYN: preganglionic nerve fibers, under fiber.
neurofibrae somaticae [TA] SYN: somatic nerve fibers, under fiber.

neurofibril
neurofibril (noor-o-fi′bril)

A filamentous structure seen with the light microscope in the nerve cell's body, dendrites, axon, and sometimes synaptic endings, as aggregations of much finer ultramicroscopic elements, the neurofilaments and microtubules; their functional significance remains to be established.

neurofibrillar
neurofibrillar (noor-o-fi′bri-ler)

Relating to neurofibrils.

neurofibroma
neurofibroma (noor′o-fi-bro′ma)

A moderately firm, benign, encapsulated tumor resulting from proliferation of Schwann cells in a disorderly pattern that includes portions of nerve fibers; in neurofibromatosis, neurofibromas are multiple. SYN: fibroneuroma.
plexiform n. a type of n., representing an anomaly rather than a true neoplasm, in which the proliferation of Schwann cells occurs from the inner aspect of the nerve sheath, thereby resulting in an irregularly thickened, distorted, tortuous structure; in some instances, the process extends along the course of the nerve and may eventually involve the spinal roots and the spinal cord; seen most frequently in neurofibromatosis. SYN: fibrillary neuroma, plexiform neuroma.
storiform n. SYN: pigmented dermatofibrosarcoma protuberans.

neurofibromatosis
neurofibromatosis (noor′o-fi-bro-ma-to′sis)

Under this heading are grouped two distinct hereditary disorders, formerly labeled peripheral and central n., but now entitled n. type 1 and type 2. Type 1 (peripheral) n., [MIM*162200] by far the most common of the two types, is characterized clinically by the combination of patches of hyperpigmentation and cutaneous and subcutaneous tumors. The hyperpigmented skin areas, present from birth and found anywhere on the body surface, can vary markedly in size and color—the dark brown ones are called café-au-lait spots. The multiple cutaneous and subcutaneous tumors, nerve sheath neoplasms, called neurofibromas, can develop anywhere along the peripheral nerve fibers, from the roots distally. Neurofibromas can become quite large, causing a major disfigurement, eroding bone, and compressing various peripheral nerve structures; a small hamartoma (Lisch nodule) can be found in the iris of almost all patients. Type 1 n., also called von Recklinghausen disease, has autosomal dominant inheritance, with the gene locus on chromosome 17q11, and is caused by mutation in the NF1 gene that encodes neurofibromin. Type 2 (central) n. [MIM*101000] has few cutaneous manifestations, and consists primarily of bilateral (less often, unilateral) acoustic neuromas, causing deafness, often accompanied by other intracranial and paraspinal neoplasms, such as meningiomas and gliomas. Type 2 n. also has autosomal dominant inheritance, but the gene locus is on 22q11, caused by mutation in the NF2 gene encoding the product merlin. SYN: elephant man's disease (2) .
abortive n. SYN: incomplete n..
central type n. type 2 n.. See n..
incomplete n. multiple neurofibromas with minimal manifestations, perhaps limited to café-au-lait spots; individuals with minimal lesions may have offspring with severe involvement. SYN: abortive n..

neurofilament
neurofilament (noor-o-fil′a-ment)

A class of intermediate filaments found in neurons.

neuroganglion
neuroganglion (noor-o-gang′le-on)

SYN: ganglion (1) .

neurogastric
neurogastric (noor-o-gas′trik)

Relating to the innervation of the stomach.

neurogenesis
neurogenesis (noor-o-jen′e-sis)

Formation of the nervous system. [neuro- + G. genesis, production]

neurogenic
neurogenic, neurogenetic (noor-o-jen′ik, -je-net′ik)

1. Originating in, starting from, or caused by, the nervous system or nerve impulses. SYN: neurogenous. 2. Relating to neurogenesis.

neurogenous
neurogenous (noo-roj′e-nus)

SYN: neurogenic (1) .

neuroglia
neuroglia (noo-rog′le-a)

Non-neuronal cellular elements of the central and peripheral nervous system; formerly believed to be merely supporting cells but now thought to have important metabolic functions, since they are invariably interposed between neurons and the blood vessels supplying the nervous system. In central nervous tissue they include oligodendroglia cells, astrocytes, ependymal cells, and microglia cells. The satellite cells of ganglia and the neurolemmal or Schwann cells around peripheral nerve fibers can be interpreted as the oligodendroglia cells of the peripheral nervous system. SYN: reticulum (2) [TA] , glia, Kölliker reticulum. [neuro- + G. glia, glue]

neurogliacyte
neurogliacyte (noo-rog′le-a-sit)

A neuroglia cell. See neuroglia. [neuro- + G. glia, glue, + kytos, cell]

neuroglial
neuroglial, neurogliar (noo-rog′le-al, -le-ar)

Relating to neuroglia.

neurogliomatosis
neurogliomatosis (noo-rog′le-o-ma-to′sis)

SYN: gliomatosis.

neurogram
neurogram (noor′o-gram)

The imprint on the brain substance theoretically remaining after every mental experience, i.e., the engram or physical register of the mental experience, stimulation of which retrieves and reproduces the original experience, thereby producing memory. [neuro- + G. gramma, something written]

neurography
neurography (noo-rog′ra-fe)

A method of depicting the state of a peripheral nerve, such as electrical recording or radiographic visualization by contrast media. [neuro- + G. grapho, to write]

neurohemal
neurohemal (noor-o-he′mal)

Descriptive of structures containing neurosecretory neurons, whose axons form no synapses with other neurons and whose axonal endings are modified to permit storage and release into the circulation of neurosecretory material. [neuro- + G. haima, blood + suffix -in, material]

neurohistology
neurohistology (noor′o-his-tol′o-je)

The microscopic anatomy of the nervous system. SYN: histoneurology.

neurohormone
neurohormone (noor-o-hor′mon)

A hormone formed by neurosecretory cells and liberated by nerve impulses ( e.g., norepinephrine).

neurohypophysial
neurohypophysial (noor′o-hi-po-fiz′e-al)

Relating to the neurohypophysis.

neurohypophysis
neurohypophysis (noor′o-hi-pof′i-sis) [TA]

It is composed of the infundibulum and the nervous lobe of the hypophysis. SEE ALSO: pituitary gland. SYN: lobus nervosus [TA] , lobus posterior hypophyseos&star, pars nervosa hypophyseos&star, nervous lobe, neural part of hypophysis, posterior lobe of hypophysis. [neuro- + hypophysis]

neuroid
neuroid (noor′oyd)

Resembling a nerve; nervelike. [neuro- + G. eidos, resemblance]

neurokeratin
neurokeratin (noor-o-kar′a-tin)

1. The proteinaceous network that remains of the myelin sheath of axons following fixation and the removal of the fatty material; the reticular appearance is probably a fixation artifact. 2. The insoluble protein matter of brain remaining after extraction with solvents following proteolytic digestion; it is unrelated to the keratins. SYN: neurochitin. [neuro- + G. keras, horn]

neurolemma
neurolemma (noor-o-lem′a)

SYN: neurilemma. [neuro- + G. lemma, husk]

neuroleptanalgesia
neuroleptanalgesia (noor′o-lept-an-al-je′ze-a)

An intense analgesic and amnesic state produced by administration of narcotic analgesics and neuroleptic drugs; unconsciousness may or may not occur, and cardiorespiratory function may be altered.

neuroleptanesthesia
neuroleptanesthesia (noor′o-lept-an-es-the′ze-ah)

A technique of general anesthesia based upon intravenous administration of neuroleptic drugs, together with inhalation of a weak anesthetic with or without neuromuscular relaxants.

neuroleptic
neuroleptic (noor-o-lep′tik)

Any of a class of psychotropic drugs used to treat psychosis, particularly schizophrenia; includes the phenothiazine, thioxanthene, and butyrophenone derivates and the dihydroindolones. SYN: n. agent. SEE ALSO: antipsychotic agent. [neuro- + G. lepsis, taking hold]

neurolinguistics
neurolinguistics (nur′o-ling-gwis′tiks)

The branch of medical science concerned with the neuroanatomic basis of speech and its disorders.

neurologist
neurologist (noo-rol′o-jist)

A specialist in the diagnosis and treatment of disorders of the neuromuscular system: the central, peripheral, and autonomic nervous systems, the neuromuscular junction, and muscle.

neurology
neurology (noo-rol′o-je)

The branch of medical science concerned with the various nervous systems (central, peripheral, and autonomic), plus the neuromuscular junction and muscle, and their disorders. [neuro- + G. logos, study]

neurolymph
neurolymph (noor′o-limf)

Obsolete term for cerebrospinal fluid. [neuro- + L. lympha, clear water]

neurolymphomatosis
neurolymphomatosis (noor′o-lim-fo-ma-to′sis)

Lymphoblastic invasion of a nerve.

neurolysin
neurolysin (nu-rol′i-sin)

An antibody causing destruction of ganglion and cortical cells, obtained by the injection of brain substance. SYN: neurotoxin (1) .

neurolysis
neurolysis (noo-rol′i-sis)

1. Destruction of nerve tissue. 2. Freeing of a nerve from inflammatory adhesions. [neuro- + G. lysis, dissolution]

neurolytic
neurolytic (noor-o-lit′ik)

Relating to neurolysis.

neuroma
neuroma (noo-ro′ma)

General term for any neoplasm derived from cells of the nervous system; on the basis of newer knowledge pertaining to cytologic and histologic characteristics, a variety of neoplasms, formerly placed in the general category of n., may now be classified in more specific categories, e.g., ganglioneuroma, neurilemoma, pseudoneuroma, and others. [neuro- + G. -oma, tumor]
acoustic n. SYN: vestibular schwannoma.
amputation n. SYN: traumatic n..
n. cutis neurofibroma of the skin.
false n. SYN: traumatic n..
fibrillary n. SYN: plexiform neurofibroma.
Morton n. SYN: Morton neuralgia.
plexiform n. SYN: plexiform neurofibroma.
n. telangiectodes a neurofibroma with a conspicuous number of blood vessels, some of which have unusually large lumens (in proportion to the thickness of the walls).
traumatic n. the nonneoplastic proliferative mass of Schwann cells and neurites that may develop at the proximal end of a severed or injured nerve. SYN: amputation n., false n., pseudoneuroma.

neuromalacia
neuromalacia (noor′o-ma-la′she-a)

Pathologic softening of nervous tissue. [neuro- + G. malakia, softness]

neuromatosis
neuromatosis (noor′o-ma-to′sis)

The presence of multiple neuromas, as in neurofibromatosis.

neuromelanin
neuromelanin (noor-o-mel′a-nin)

A modified form of melanin pigment normally found in certain neurons of the nervous system, especially in the substantia nigra and locus ceruleus.

neuromeningeal
neuromeningeal (noor-o-me-nin′je- al)

Related to involvement of nervous tissue and the meninges.

neuromere
neuromere (noor′o-mer)

Elevations in the wall of the developing neural tube that divide the developing spinal cord (n.) into portions to which dorsal and ventral roots are attached, or that divide the developing rhombencephalon into portions associated primarily with motor portions of the cranial nerves of the medulla and pons. SYN: encephalomere, neural segment, neurotome (2) . [neuro- + G. meros, part]

neuromimetic
neuromimetic (noor′o-mi-met′ik)

Relating to the action of a drug that mimics the response of an effector organ to nerve impulses.

neuromuscular
neuromuscular (noor-o-mus′ku-lar)

Referring to the relationship between nerve and muscle, in particular to the motor innervation of skeletal muscles and its pathology ( e.g., n. disorders). SEE ALSO: myoneural.

neuromyasthenia
neuromyasthenia (noor′o-mi-as-the′ne-a)

Obsolete term for muscular weakness, usually of emotional origin. [neuro- + G. mys, muscle, + a- priv. + sthenos, strength]
epidemic n. an epidemic disease characterized by stiffness of the neck and back, headache, diarrhea, fever, and localized muscular weakness; restricted almost exclusively to adults, affecting women more than men; probably viral in origin. SYN: benign myalgic encephalomyelitis, epidemic myalgic encephalomyelitis, Iceland disease.

neuromyelitis
neuromyelitis (noor′o-mi-el-i′tis)

Neuritis combined with spinal cord inflammation. SYN: myeloneuritis. [neuro- + G. myelos, marrow, + -itis, inflammation]
n. optica a demyelinating disorder consisting of a transverse myelopathy and optic neuritis. SYN: Devic disease.

neuromyopathy
neuromyopathy (noor′o-mi-op′a-the)

1. A disorder of muscle due to disorder of its nerve supply. 2. Simultaneous disorders of nerve and muscles. [neuro- + G. mys, muscle, + pathos, disease]
carcinomatous n. n. associated with carcinoma, especially of the lung.

neuromyositis
neuromyositis (noor′o-mi-o-si′tis)

Obsolete term for polymyositis. [neuro- + G. mys, muscle, + -itis, inflammation]

neuron
neuron (noor′on)

The morphologic and functional unit of the nervous system, consisting of the nerve cell body, the dendrites, and the axon. SYN: nerve cell, neurocyte, neurone. [G. n., a nerve]
autonomic motor n. motor n..
bipolar n. a n. that has two processes arising from opposite poles of the cell body.
gamma motor neurons SYN: gamma loop.
ganglionic motor n. motor n..
Golgi type I n. nerve cells whose long axons leave the gray matter of which they form a part.
Golgi type II n. nerve cells with short axons that ramify in the gray matter.
intercalary n. SYN: internuncial n..
internuncial n. a n. interposed between and connecting two other neurons. SYN: intercalary n..
lower motor n. clinical term used to indicate the final motor neurons that innervate the skeletal muscles; distinguished from upper motor neurons of the motor cortex that contribute to the corticospinal tract. SEE ALSO: motor n..
motor n. a nerve cell in the spinal cord, rhombencephalon, or mesencephalon characterized by having an axon that leaves the central nervous system to establish a functional connection with an effector (muscle or glandular) tissue; somatic motor neurons directly synapse with striated muscle fibers by motor endplates; visceral motor neurons or autonomic motor neurons (preganglionic m. neurons), by contrast, innervate smooth muscle fibers or glands only by the intermediary of a second, peripheral, n. (postganglionic m. n.) located in an autonomic, or visceral motor, ganglion. SEE ALSO: motor endplate, autonomic division of nervous system. SYN: anterior horn cell, motoneuron.
multipolar n. a n. with several processes, usually an axon and three or more dendrites.
NANC n. abbreviation for nonadrenergic, noncholinergic n..
nonadrenergic, noncholinergic n. (NANC n.) autonomic efferent n. whose transmission is not blocked by blocking adrenergic and cholinergic transmission. Nitric oxide may be the transmitter in some cases.
polymorphic n. occurring in many shapes. SEE ALSO: multipolar cell.
postganglionic motor n. motor n..
preganglionic motor n. motor n..
pseudounipolar n. SYN: unipolar n..
sensory n. a n. conveying information originating from sensory receptors or nerve endings; afferent n., may be general or special sensory.
somatic motor n. motor n..
unipolar n. a n. whose cell body emits a single axonal process resulting from the fusion of two polar processes during development; at a variable distance from the cell body, the process divides into a peripheral axon branch extending outward as a peripheral afferent (sensory) nerve fiber and a central axon branch that enters into synaptic contact with neurons in the spinal cord or brainstem. With the single known exception of the neurons composing the mesencephalic nucleus of the trigeminus, unipolar neurons are the exclusive neural elements of the sensory ganglia. The lack of dendritic processes of these primary sensory neurons is only apparent: the dendritic pole of the unipolar n. is represented by the unmyelinated terminal ramifications of the peripheral axon branch. SYN: pseudounipolar cell, pseudounipolar n., unipolar cell.
upper motor n. clinical term indicating those neurons of the motor cortex that contribute to the formation of the corticospinal and corticonuclear (corticobulbar) tracts, as distinguished from the lower motor neurons innervating the skeletal muscles. Although not motor neurons in the strict sense, these cortical neurons became colloquially classified as motor neurons because their stimulation produces movement and their destruction causes moderate to severe disorders of movement. SEE ALSO: motor n., motor cortex.
visceral motor n. motor n..

neuronal
neuronal (noor′o-nal, noo-ro′nal)

Pertaining to a neuron.

neurone
neurone (noor′on)

SYN: neuron.

neuronephric
neuronephric (noor-o-nef′rik)

Relating to the nerve supply of the kidney. [neuro- + G. nephros, kidney]

neuronevus
neuronevus (noor-o-ne′vus)

A variety of intradermal nevus in adults in which nests of atrophic nevus cells in the lower dermis are hyalinized and resemble nerve bundles.

neuronitis
neuronitis (noor-o-ni′tis)

Inflammatory disorder of the neuron.
vestibular n. a paroxysmal attack of severe vertigo, not accompanied by deafness or tinnitus, which affects young to middle-aged adults, often following a nonspecific upper respiratory infection; due to unilateral vestibular dysfunction. SYN: endemic paralytic vertigo, epidemic vertigo, Gerlier disease, kubisagari, kubisagaru, paralyzing vertigo.

neuronopathy
neuronopathy (noor-o-nop′a-the)

Disorder, often toxic, of the neuron (1).
sensory n. n. confined to dorsal root and gasserian ganglia.
X-linked recessive bulbospinal n. SYN: Kennedy disease.

neuronophage
neuronophage (noo-ron′o-faj)

A phagocyte that ingests neuronal elements. See microglia. [neuron + G. phago, to eat]

neuronophagia
neuronophagia, neuronophagy (noor′on′o-fa′je-a, noor-o-nof′a-je)

Phagocytosis of nerve cells. [neuron + G. phago, to eat]

neuronyxis
neuronyxis (noor-o-nik′sis)

Acupuncture of a nerve. [neuro- + G. nyxis, pricking]

neuro-oncology
neuro-oncology (noor′o-on-kol′o-je)

The branch of medicine concerned with the direct and indirect effects of neoplasms on the nervous system, neuromuscular junction, and muscle. [neuro- + onco- + G. logos, study]

neuro-ophthalmology
neuro-ophthalmology (noor′o-of-thal-mol′o-je)

The branch of medicine concerned with the neurological aspects of the visual apparatus.

neurootology
neurootology (noor′o-o-tol′o-je)

The branch of medicine concerned with the nervous system related to the auditory and vestibular systems.

neuroparalysis
neuroparalysis (noor′o-pa-ral′i-sis)

Paralysis resulting from disease of the nerve supplying the affected part.

neuroparalytic
neuroparalytic (noor′o-pa-ra-lit′ik)

Denoting or characterized by neuroparalysis.

neuropath
neuropath (noor′o-path)

One who suffers from or is predisposed to some disease of the nervous system.

neuropathia
neuropathia (noo-ro-path′e-a)

SYN: neuropathy.
n. epidemica hemorrhagic fever with renal complications; due to Puumala virus.

neuropathic
neuropathic (noor-o-path′ik)

Relating in any way to neuropathy.

neuropathogenesis
neuropathogenesis (noor′o-path-o-jen′e-sis)

The origin or causation of a disease of the nervous system. [neuro- + G. pathos, suffering, + genesis, origin]

neuropathology
neuropathology (noor′o-pa-thol′o-je)

1. Pathology of the nervous system. 2. That branch of pathology concerned with the nervous system.

neuropathy
neuropathy (noo-rop′a-the)

1. A classical term for any disorder affecting any segment of the nervous system. 2. In contemporary usage, a disease involving the cranial nerves or the peripheral or autonomic nervous system. SYN: neuritis (2) , neuropathia. [neuro- + G. pathos, suffering]
acute motor axonal n. an acute, pure motor axon-degenerating type of polyradiculoneuropathy, a variant of Guillain-Barré syndrome; seen principally in a seasonal pattern (spring or summer) among children in rural China following epidemics of diarrhea caused by Campylobacter jejuni.
acute sensory motor axonal n. an acute axon-degenerating polyradiculoneuropathy that affects both motor and sensory fibers; a variant of Guillain-Barré syndrome.
asymmetric motor n. 1. n. in which the loss of function is more marked in the extremities of one side of the body; 2. one presentation of diabetic amyotrophy.
auditory n. a disorder of hearing in children characterized by sensorineural hearing loss for pure tones, reduced word discrimination disproportionate to the pure-tone loss, normal outer hair cell function as determined by measurement of otoacoustic emissions, and absent or abnormal auditory brainstem response.
brachial plexus n. SYN: neuralgic amyotrophy.
compression n. a focal nerve lesion produced when sustained pressure is applied to a localized portion of the nerve, either from an external or internal source; the main source of injury is the pressure differential that exists between one portion of the nerve and another.
dapsone n. a polyneuropathy that develops in patients taking dapsone (4,4-diaminodiphenylsulfone); unusual features include being a pure motor n. and beginning in the hands, sometimes asymmetrically. SYN: motor dapsone n..
diabetic n. a generic term for any diabetes mellitus–related disorder of the peripheral nervous system, autonomic nervous system, and some cranial nerves.This most common of the chronic complications of diabetes can affect either the peripheral or the autonomic nervous system, or both. Peripheral neuropathies can cause bilaterally symmetric hypesthesia, hyperesthesia, paresthesia, loss of temperature and vibratory sense, or causalgia. Involvement of the autonomic nervous system may be manifested by postural hypotension, gastroparesis, alternating diarrhea and constipation, and impotence. The pathogenesis of chronic diabetic n. is poorly understood. Symptoms tend to progress, and the response to treatment is unpredictable. In contrast, cranial nerve palsies due to microangiopathy in diabetes mellitus often resolve spontaneously.
diphtheritic n. a rapidly developing polyneuropathy caused by a toxin elaborated by Corynebacterium diphtheriae.
entrapment n. a focal nerve lesion produced by constriction or mechanical distortion of the nerve, within a fibrous or fibro-osseous tunnel, or by a fibrous band; with these lesions, stretching and angulation of the nerve may be as important a source of injury as compression; entrapment neuropathies tend to occur at particular sites in the body.
familial amyloid n. [MIM*105120, various kinds] a disorder in which various peripheral nerves are infiltrated with amyloid and their functions disturbed, an abnormal prealbumin is also formed and is present in the blood; characteristically, it begins during midlife and is found largely in persons of Portuguese descent; autosomal dominant inheritance. Other rare clinical types occur. SYN: familial amyloidosis, hereditary amyloidosis.
giant axonal n. a rare disorder beginning at or after the third year of life, and presenting clinically with kinky hair, progressive painless clumsiness, muscle weakness and atrophy, sensory loss, and areflexia. Pathologically, both myelinated and unmyelinated nerve fibers contain axonal spheroids packed with neurofilaments; sporadic in nature.
Graves optic n. visual dysfunction due to optic nerve compression in Graves orbitopathy.
heavy metal n. peripheral nervous system disorders attributed to intoxication of one of the heavy metals: arsenic, gold, lead, mercury, platinum, and thallium.
hereditary hypertrophic n. [MIM*145900] SYN: Dejerine-Sottas disease.
hereditary sensory radicular n. [MIM*162400] polyneuropathy characterized by the occurrence of severe, relapsing foot ulcerations of neuropathic origin, destruction of terminal digits of feet and hands, and a loss of sensation; autosomal dominant inheritance is associated with onset in the second decade or later.
hypertrophic interstitial n. sensorimotor polyneuropathy characterized pathologically by collections of Schwann cell processes arranged concentrically around one or more nerve fibers. No genetic factors are known in its etiology.For hereditary types, see hereditary hypertrophic n..
ischemic n. n. resulting from acute or chronic ischemia of the involved nerves.
ischemic optic n. optic nerve n. secondary to hypoperfusion of the low pressure posterior ciliary arteries supplying the optic nerve head (nonarteritic) or to temporal arteritis (arteritic).
isoniazid n. axon loss; type of polyneuropathy seen in some patients treated with isoniazid.
lead n. a polyneuropathy reportedly seen in chronic lead intoxication; reputedly characterized by wrist-drop, but no convincing modern reports of this are available.
leprous n. a slowly developing granulomatous n., commonly seen in leprosy, caused by Mycobacterium leprae.
motor dapsone n. SYN: dapsone n..
onion bulb n. designation for any of several demyelinating polyneuropathies in which the nerves are enlarged because of onion bulb formation—whorls of overlapping Schwann cell processes encircling bare medullated axons; e.g., progressive hypertrophic polyneuropathy. See hypertrophic interstitial n..
symmetric distal n. SYN: polyneuropathy.
vitamin B₁₂ n. SYN: subacute combined degeneration of the spinal cord.

neuropeptide
neuropeptide (noor-o-pep′tid)

Any of a variety of peptides found in neural tissue; e.g., endorphins, enkephalins.
n. Y a 36–amino acid peptide neurotransmitter found in the brain and autonomic nervous system. It augments the vasoconstrictor effects of noradrenergic neurons.

neuropharmacology
neuropharmacology (noor′o-far′ma-kol′o-je)

The study of drugs that affect neuronal tissue.

neurophilic
neurophilic (noor-o-fil′ik)

SYN: neurotropic. [neuro- + G. philos, fond]

neurophonia
neurophonia (noor-o-fo′ne-a)

A spasm or tic of the muscles of phonation causing involuntary sounds or cries. [neuro- + G. phone, voice]

neurophysins
neurophysins (noor-o-fiz′inz)

A family of proteins synthesized in the hypothalamus as part of the large precursor protein that includes vasopressin and oxytocin in the neurosecretory granules; n. function as carriers in the transport and storage of neurohypophysial hormones.

neurophysiology
neurophysiology (noor′o-fiz-e-ol′o-je)

Physiology of the nervous system.

neuropil
neuropil, neuropile (noor′o-pil, -pil)

The complex, feltlike net of axonal, dendritic, and glial arborizations that forms the bulk of the central nervous system's gray matter, and in which the nerve cell bodies lie embedded. [neuro- + G. pilos, felt]

neuroplasm
neuroplasm (noor′o-plazm)

The protoplasm of a nerve cell.

neuroplasty
neuroplasty (noor′o-plas-te)

Surgery of the nerves. [neuro- + G. plastos, formed]

neuroplegic
neuroplegic (noor-o-ple′jik)

Pertaining to paralysis due to nervous system disease. [neuro- + G. plege, a stroke]

neuroplexus
neuroplexus (noo′ro-plek′sus)

A plexus or network of nerve cells or fibers.

neuropodia
neuropodia (noor-o-po′de-a)

SYN: axon terminals, under terminal. [pl. of neuropodium or neuropodion, fr. neuro- + G. podion, little foot]

neuropore
neuropore (noor′o-por)

An opening in the embryo leading from the central canal of the neural tube to the exterior of the tube. [neuro- + G. poros, pore]
anterior n. SYN: rostral n..
caudal n. the temporary opening at the extreme caudal end of the neural tube in early embryos; closes at approximately the 25th somite stage in humans. SYN: posterior n..
cranial n. SYN: rostral n..
posterior n. SYN: caudal n..
rostral n. the temporary opening at the extreme rostral (cephalic) end of the early embryonic forebrain; closes at approximately the 20th somite stage in humans. SYN: anterior n., cranial n..

neuropraxia
neuropraxia

Commonly used misspelling of neurapraxia.

neuropsychiatry
neuropsychiatry (noor′o-si-ki′a-tre)

The specialty dealing with both organic and psychic disorders of the nervous system; earlier term for psychiatry.

neuropsychologic
neuropsychologic, neuropsychological (noor′o-si-ko-loj′ik, -loj′i-kal)

Pertaining to neuropsychology.

neuropsychology
neuropsychology (noor′o-si-kol′o-je)

A specialty of psychology concerned with the study of the relationships between the brain and behavior, including the use of psychological tests and assessment techniques to diagnose specific cognitive and behavioral deficits and to prescribe rehabilitation strategies for their remediation.

neuropsychopathic
neuropsychopathic (noor′o-si-ko-path′ik)

Relating to neuropsychopathy.

neuropsychopathy
neuropsychopathy (noor′o-si-kop′a-the)

An emotional illness of neurologic origin.

neuropsychopharmacology
neuropsychopharmacology (noor′o-si′ko-far-ma-kol′o-je)

SYN: psychopharmacology.

neuroradiology
neuroradiology (noor′ro-ra-de-ol′o-je)

The clinical subspecialty concerned with the diagnostic radiology of diseases of the central nervous system, head, and neck.

neuroregulator
neuroregulator (noor′o-reg′u-la-tor)

A chemical factor that extends a modulatory effect on a neuron.

neurorelapse
neurorelapse (noor′o-re-laps′)

Obsolete term for the recurrence of neurological symptoms upon initiation of therapy, especially with antisyphilitic drugs.

neuroretinitis
neuroretinitis (noor′o-ret-i-ni′tis)

An inflammation affecting the optic nerve head and the posterior pole of the retina, with cells in the nearby vitreous, usually producing a macular star. SYN: papilloretinitis.
diffuse unilateral subacute n. (DUSN) inflammation of the neurosensory retina caused by infiltration by a roundworm such as Baylisascaris or Ancylostoma species.
Leber idiopathic stellate n. SYN: stellate n..
stellate n. a unilateral n. with perifoveal exudates in Henle nerve fiber layer producing a macular star and spontaneous regression in a few months. SYN: Leber idiopathic stellate n..

neurorrhaphy
neurorrhaphy (noor-or′a-fe)

Joining together, usually by suture, of the two parts of a divided nerve. SYN: nerve suture, neurosuture. [neuro- + G. rhaphe, suture]

neurosarcocleisis
neurosarcocleisis (noor′o-sar-ko-kli′sis)

An operation for the relief of neuralgia, consisting of resection of one of the walls of an osseous canal traversed by the nerve and transposition of the nerve into the soft tissues. [neuro- + G. sarx, flesh, + kleisis, closure]

neurosarcoidosis
neurosarcoidosis (noor′o-sar-koy-do′sis)

A granulomatous disease of unknown etiology involving the central nervous system, usually with concomitant systemic involvement.

neurosarcoma
neurosarcoma (noo′ro-sar-ko′ma)

A sarcoma with neuromatous elements; includes neurofibrosarcoma, neurogenic sarcoma, and malignant schwannoma.

neuroschwannoma
neuroschwannoma (noor′o-shwah-no′ma)

SYN: schwannoma.

neurosciences
neurosciences (noor-o-si′en-sez)

The scientific disciplines concerned with the development, structure, function, chemistry, pharmacology, clinical assessments, and pathology of the nervous system.

neurosecretion
neurosecretion (noor′o-se-kre′shun)

The release of a secretory substance from the axon terminals of certain nerve cells in the brain into the circulating blood. The secretory product may be a true hormone, e.g., the antidiuretic hormone released from the axon terminals of the neurons composing the supraoptic nucleus of the hypothalamus; in the case of the so-called releasing-factor neurons of the hypothalamus the cell product is not a systemic hormone in its own right but elicits the release of trophic hormones by the anterior lobe of the hypophysis, substances that in turn stimulate peripheral endocrine glands to release their systemically active hormones.

neurosecretory
neurosecretory (noor′o-se′kre-tor-e, -se-kre′tor-e)

Relating to neurosecretion.

neurosis
neurosis, pl .neuroses (noo-ro′sis, -sez)

1. A psychological or behavioral disorder in which anxiety is the primary characteristic; defense mechanisms or any of the phobias are the adjustive techniques that an individual learns in order to cope with this underlying anxiety. In contrast to the psychoses, persons with a n. do not exhibit gross distortion of reality or disorganization of personality. 2. A functional nervous disease, or one for which there is no evident lesion. 3. A peculiar state of tension or irritability of the nervous system; any form of nervousness. SYN: neurotic disorder. [neuro- + G. -osis, condition]
accident n. SYN: traumatic n..
anxiety n. chronic abnormal distress and worry to the point of panic followed by a tendency to avoid or run from the feared situation, associated with overaction of the sympathetic nervous system.
cardiac n. anxiety concerning the state of the heart, as a result of palpitation, chest pain, or other symptoms not due to heart disease; a form of hypochondriasis. SYN: cardioneurosis.
character n. a subclass of personality disorders.
combat n. battle fatigue, posttraumatic stress disorder.
compensation n. the development of symptoms of n. believed to be motivated by the desire for, and hope of, monetary or interpersonal gain.
compulsive n. SYN: obsessive-compulsive n..
conversion n. SYN: conversion hysteria.
conversion hysteria n. SYN: conversion hysteria.
depressive n. See depression, dysthymia.
experimental n. a behavior disorder produced experimentally, as when an organism is required to make a discrimination of extreme difficulty and “breaks down” in the process.
hypochondriacal n. SYN: hypochondriasis.
hysterical n. a bona fide disorder characterized by an alteration or loss of physical functioning, such as blurred vision, numbness or paralysis of limbs, coordination difficulties, etc., that suggests a physical disorder, but that instead is apparently an expression of a psychological conflict or need. Also called conversion disorder. SEE ALSO: hysteria.
noogenic n. in existential psychiatry, the neurotic symptomatology resulting from existential frustration.
obsessional n. SYN: obsessive-compulsive n..
obsessive-compulsive n. a disorder characterized by the persistent and repetitive intrusion of unwanted thoughts, urges, or actions that the individual is unable to prevent; the compulsive thoughts may consist of single words, ideas, or ruminations often perceived by the sufferer as nonsensical; the repetitive urges or actions vary from simple movements to complex rituals; anxiety or distress is the underlying emotion or drive state, and the ritualistic behavior is a learned method of reducing the anxiety. SEE ALSO: obsessive-compulsive disorder. SYN: compulsive n., obsessional n..
oedipal n. continuation of the Oedipus complex into adulthood.
pension n. a type of compensation n., motivated by the desire for premature retirement on pension.
posttraumatic n. SYN: traumatic n..
torsion n. SYN: dysbasia lordotica progressiva.
transference n. in psychoanalysis, the phenomenon of the patient's developing a strong emotional relationship with the analyst, symbolizing an emotional relationship with a family figure; analysis of this n. constitutes an important part of psychoanalytic treatment.
traumatic n. any functional nervous disorder following an accident or injury. See posttraumatic stress disorder. SYN: accident n., posttraumatic n..

neurosplanchnic
neurosplanchnic (noor-o-splangk′nik)

SYN: neurovisceral. [neuro- + G. splanchnon, a viscus]

neurospongium
neurospongium (noor-o-spon′je-um, noor-o-spun′je-um)

1. Obsolete term for the plexus of neurofibrils within nerve cells. 2. Obsolete designation for the reticular layer of the retina. [neuro- + G. spongion, small sponge]

Neurospora
Neurospora (noo-ros′por-a)

A genus of fungi (class Ascomycetes) grown in cultures and used in research in genetics and cellular biochemistry. SYN: pink bread mold. [neuro- + G. spora, seed]

neurosteroid
neurosteroid (nur-o-ster′oyd)

Steroid produced within the brain.

neurostimulator
neurostimulator (noor-o-stim′u-la-ter)

A device for electrical excitation of the central or peripheral nervous system.

neurosurgeon
neurosurgeon (noor-o-ser′jun)

A surgeon specializing in operations on the brain, spinal cord, spinal column, and peripheral nerves.

neurosurgery
neurosurgery (noor-o-ser′jer-e)

Surgery of the nervous system.
functional n. destruction or chronic excitation of a part of the brain to treat disordered behavior or function.

neurosuture
neurosuture (noor-o-soo′choor)

SYN: neurorrhaphy.

neurosyphilis
neurosyphilis (noor-o-sif′i-lis)

Infection of the central nervous system by Treponema pallidum, or syphilis; there are several subdivisions, including asymptomatic n., meningeal n., meningovascular n., paretic n., and tabetic n..
asymptomatic n. clinically inapparent (except for possible abnormal pupils) syphilitic meningeal infection, diagnosed by examination of the cerebrospinal fluid; if untreated, often develops into some form of symptomatic n..
meningeal n. syphilitic meningeal infection producing an afebrile clinical meningitis, with headache, stiff neck, obtusion, etc., and abnormal CSF findings. Most often develops within 2 years of initial infection.
meningovascular n. syphilitic meningeal infection accompanied by changes (inflammation, fibrous thickening) in the walls of the subarachnoid arteries, manifested as a stroke, with sudden onset of symptoms such as hemiplegia, aphasia, visual disturbances, etc., and abnormal CSF findings.
paretic n. syphilitic infection manifested as dementia (often with delusional features), dysarthria, seizures, myoclonic jerks, action tremor, impaired walking and standing, pupillary abnormalities, and abnormal CSF findings. SYN: chronic progressive syphilitic meningoencephalitis, general paresis.
tabetic n. type of n. in which the posterior roots of the spinal cord, especially in the lumbosacral area, are the principal sites of infection, resulting in ataxia, hypotonia, impotence, constipation, hypotonic bladder, areflexia, and Romberg sign; other findings include lancinating pains (most often in the legs), visceral crises, Argyll Robertson pupils, optic atrophy, and Charcot joints; in most patients, the CSF is abnormal. SYN: myelosyphilis, posterior sclerosis, posterior spinal sclerosis.

neurotaxis
neurotaxis (noor′o-tak′sis)

Neuronal elongation in the direction of a target. [neuro- + taxis, arrangement]

neurotendinous
neurotendinous (noor-o-ten′di-nus)

Relating to both nerves and tendons.

neurotensin
neurotensin (noo-ro-ten′sin)

A 13–amino acid peptide neurotransmitter found in synapsomes in the hypothalamus, amygdala, basal ganglia, and dorsal gray matter of the spinal cord; it plays a role in pain perception, but its analgesic effects are not blocked by opioid antagonists; it also affects pituitary hormone release and gastrointestinal function.

neurotension
neurotension (noor-o-ten′shun)

SYN: neurectasis.

neurothekeoma
neurothekeoma (noor-o-the-ke-o′ma)

A benign myxoma of cutaneous nerve sheath origin. [neuro- + G. theke, box, sheath, + -oma, tumor]

neurothele
neurothele (noor′o-thel)

SYN: nerve papilla. [neuro- + G. thele, nipple]

neurotherapeutics
neurotherapeutics, neurotherapy (noor′o-thar′a-pu′tiks, -thar′a-pe)

An older term for the treatment of psychological, psychiatric, and nervous disorders.

neurotic
neurotic (noo-rot′ik)

Relating to or suffering from a neurosis. See neurosis.

neuroticism
neuroticism (noo-rot′i-sizm)

The condition or psychological trait of being neurotic.

neurotization
neurotization (noor′o-ti-za′shun)

The acquisition of nervous substance; the regeneration of a nerve.

neurotize
neurotize (noor′o-tiz)

To provide with nerve substance.

neurotmesis
neurotmesis

A type of axon loss lesion resulting from focal peripheral nerve injury in which, at the lesion site, the nerve stroma is damaged to varying degrees, as well as the axon and myelin, which degenerate from that point distally; with the most severe n. lesions, the gross continuity of the nerve is disrupted. See axonotmesis, neurapraxia.

neurotome
neurotome (noor′o-tom)

1. A very slender knife or needle, used for teasing apart nerve fibers in microdissection. 2. SYN: neuromere. [neuro- + G. tome, a cutting]

neurotomy
neurotomy (noo-rot′o-me)

Operative division of a nerve. [neuro- + G. tome, a cutting]
retrogasserian n. SYN: trigeminal rhizotomy.

neurotonic
neurotonic (noor-o-ton′ik)

1. Relating to neurotony. 2. Strengthening or stimulating impaired nervous action. 3. An agent that improves the tone or force of the nervous system.

neurotoxic
neurotoxic (noor-o-tok′sik)

Poisonous to nervous substance.

neurotoxin
neurotoxin (noor-o-tok′sin)

1. SYN: neurolysin. 2. Any toxin that acts specifically on nervous tissue.

neurotransmission
neurotransmission (noor′o-trans-mish′un)

SYN: neurohumoral transmission.

neurotransmitter
neurotransmitter (noor′o-trans-mit′er)

Any specific chemical agent (including acetylcholine, five amines, four amino acids, two purines, and more than 28 peptides) released by a presynaptic cell, upon excitation, that crosses the synapse to stimulate or inhibit the postsynaptic cell. More than one may be released at any given synapse. The neurotransmitters released by presynaptic cells may modulate transmitter release from presynaptic cells. Nitric oxide may be a retrograde n., released from postsynaptic cells, to act on presynaptic cells. [neuro- + L. transmitto, to send across]
adrenergic n. a n. formed in sympathetic postganglionic synapses ( E.G., norepinephrine).
cholinergic n. a n. formed in pre- and postganglionic synapses of the parasympathetic nervous system ( E.G., acetylcholine).

neurotrauma
neurotrauma (noor-o-traw′ma)

1. Trauma of the nervous system. 2. Trauma or wounding of a nerve. SYN: neurotrosis. [neuro- + G. trauma, injury]

neurotripsy
neurotripsy (noor-o-trip′se)

Operative crushing of a nerve. [neuro- + G. tripsis, a rubbing]

neurotrophic
neurotrophic (noor-o-trof′ik)

Relating to neurotrophy.

neurotrophy
neurotrophy (noo-rot′ro-fe)

Nutrition and metabolism of tissues under nervous influence. [neuro- + G. trophe, nourishment]

neurotropic
neurotropic (noor-o-trop′ik)

Having an affinity for the nervous system. SYN: neurophilic.

neurotropy
neurotropy, neurotropism (noo-rot′ro-pe, -pizm)

1. Affinity of basic dyes for nervous tissue. 2. The attraction of certain pathogenic microorganisms, poisons, and nutritive substances toward the nerve centers. [neuro- + G. trope, a turning]

neurotrosis
neurotrosis (noor-o-tro′sis)

SYN: neurotrauma (2) . [neuro- + G. trosis, a wounding]

neurotubule
neurotubule (noor′o-too-bul)

One of the microtubules, about 24 nm in diameter, occurring in the cell body, dendrites, axon, and some synaptic endings of neurons.

neurovaccine
neurovaccine (noor-o-vak′sen)

A fixed or standardized vaccine virus of definite strength, obtained by continued passage through the brain of rabbits; old way to prepare rabies vaccine.

neurovaricosis
neurovaricosis, neurovaricosity (noor′o-var-i-ko′sis, -var-i-kos′i-te)

A condition marked by multiple swellings along the course of a nerve. [neuro- + L. varix, varicosis]

neurovascular
neurovascular (noor-o-vas′ku-lar)

Relating to both nervous and vascular systems; relating to the nerves supplying the walls of the blood vessels, the vasomotor nerves.

neurovegetative
neurovegetative (noor-o-vej′e-ta-tiv)

SYN: neurovisceral.

neurovirus
neurovirus (noor-o-vi′rus)

Vaccine virus modified by means of passage into and growth in nervous tissue.

neurovisceral
neurovisceral (noor-o-vis′er-al)

Referring to the innervation of the internal organs by the autonomic (visceral motor) nervous system. SYN: neurosplanchnic, neurovegetative. [neuro- + L. viscera, the internal organs]

neurula
neurula, pl .neurulae (noor′oo-la, -le)

Stage in embryonic development in which the prominent processes are the formation of the neural plate and the plate's closure to form the neural tube. [neur- + L. -ulus, small one]

neurulation
neurulation (noor-oo-la′shun)

Formation of the neural plate and its closure to form the neural tube. [see neurula]

Neusser
Neusser

Edmund von, Austrian physician, 1852–1912. See N. granules, under granule.

neutral
neutral (noo′tral)

1. Exhibiting no positive properties; indifferent. 2. In chemistry, neither acid nor alkaline, i.e., [OH⁻] = [H⁺]. 3. Having the same number of positive and negative charges. [L. neutralis, fr. neuter, neither]

neutralization
neutralization (noo′tral-i-za′shun)

1. The change in reaction of a solution from acid or alkaline to neutral by the addition of just a sufficient amount of an alkaline or of an acid substance, respectively. 2. The rendering ineffective of any action, process, or potential.
viral n. the elimination of viral infectivity as with specific antibodies.

neutralize
neutralize (noo′tra-liz)

To effect neutralization.

neutral red
neutral red [C.I. 50040]

Used as an indicator (red at pH 6.8, yellow at 8.0), as a vital dye to stain granules and vacuoles in living cells, in testing the secretion of acid by the stomach (given with a test meal), and in general histologic staining. SYN: toluylene red.

neutro- neutro-, neutr-

Neutral. [L. neutralis, fr. neuter, neither]

neutroclusion
neutroclusion (noo-tro-kloo′zhun)

A malocclusion in which there is a normal anteroposterior relationship between the maxilla and mandible; in Angle classification, a Class I malocclusion. SYN: neutral occlusion (2) . [neutro- + occlusion]

neutron
neutron (noo′tron)

An electrically neutral particle in the nuclei of all atoms (except hydrogen-1) with a mass slightly larger than that of a proton; in isolation, it has a half-life of about 10.3 minutes. [L. neuter, neither]
epithermal n. a n. having an energy in the range immediately above the thermal range, i.e., having an energy between a few hundredths and approximately 100 ev.

neutropenia
neutropenia (noo-tro-pe′ne-a)

The presence of abnormally small numbers of neutrophils in the circulating blood. SYN: neutrophilic leukopenia, neutrophilopenia. [neutrophil + G. penia, poverty]
cyclic n. SYN: periodic n..
periodic n. n. recurring at regular intervals (14–45 days), in association with various types of infectious diseases, e.g., stomatitis, cutaneous ulcers, furuncles, arthritis, and others. SYN: cyclic n..

neutrophil
neutrophil, neutrophile (noo′tro-fil, -fil)

1. A mature white blood cell in the granulocytic series, formed by myelopoietic tissue of the bone marrow (sometimes also in extramedullary sites), and released into the circulating blood, where they normally represent 54–65% of the total number of leukocytes. When stained with the usual Romanovsky type of dyes, neutrophils are characterized by 1) a nucleus that is dark purple-blue, lobated (three to five distinct lobes joined by thin strands of chromatin), and with a rather coarse network of fairly dense chromatin; and 2) a cytoplasm that is faintly pink (sharply contrasted with the nucleus) and contains numerous fine pink or violet-pink granules, i.e., not acidophilic or basophilic (as in eosinophils or basophils). The precursors of neutrophils, in order of increasing maturity, are: myeloblasts, promyelocytes, myelocytes, metamyelocytes, and band forms. Although the terms neutrophilic leukocytes and neutrophilic granulocytes include younger cells in which neutrophilic granules are recognized, the two expressions are frequently used as synonyms for neutrophils, which are mature forms unless otherwise indicated by a modifying term, such as immature n.. SEE ALSO: leukocyte, leukocytosis. 2. Any cell or tissue that manifests no special affinity for acid or basic dyes, i.e., the cytoplasm stains approximately equally with either type of dye. [neutro- + G. philos, fond]
band n. SYN: band cell.
hypersegmented n. an aged and degenerated n. in which there may be 6 to 10 lobes in the nucleus.
immature n. a young n.; the term is usually used with reference to stab neutrophils (or other “juvenile” neutrophils), neutrophilic granulocytes in which the nucleus is indented but not distinctly segmented.
juvenile n. any cell of the granulocytic series in which the neutrophilic granules are recognizable and the nucleus is indented (the first phase of segmentation).
mature n. SYN: segmented n..
segmented n. a fully matured n. that has at least 2 (and as many as 5) distinct lobes in the nucleus and manifests active ameboid motion. SYN: mature n..
stab n. SYN: band cell.

neutrophilia
neutrophilia (noo-tro-fil′e-a)

An increase of neutrophilic leukocytes in blood or tissues; also frequently used synonymously with leukocytosis, inasmuch as the latter is generally the result of an increased number of neutrophilic granulocytes in the circulating blood (or in the tissues, or both). N. is usually absolute, i.e., there is an increase in the total number of leukocytes as well as an increased percentage of neutrophils; in some instances, n. may be relative ( i.e., there is an increased percentage of neutrophils), but the total number of all types of leukocytes may be within the normal range. SYN: neutrophilic leukocytosis.

neutrophilic
neutrophilic (noo-tro-fil′ik)

1. Pertaining to or characterized by neutrophils, such as an exudate in which the predominant cells are n. granulocytes. 2. Characterized by a lack of affinity for acid or basic dyes, i.e., staining approximately equally with either type. SYN: neutrophilous.

neutrophilopenia
neutrophilopenia (noo′tro-fil-o-pe′ne-a)

SYN: neutropenia. [neutrophil + G. penia, poverty]

neutrophilous
neutrophilous (noo-trof′i-lus)

SYN: neutrophilic (2) .

neutrotaxis
neutrotaxis (noo-tro-tak′sis)

A phenomenon in which neutrophilic leukocytes are stimulated by a substance in such a manner that they are either attracted, and move toward it (positive n.), or they are repelled, and move away from it (negative n.); in some instances, there is no effect (sometimes called indifferent n.). [neutrophil + G. taxis, arrangement]

nevi
nevi (ne′vi)

Plural of nevus. [L.]

nevocyte
nevocyte (ne′vo-sit)

SYN: nevus cell.

nevoid
nevoid (ne′voyd)

Resembling a nevus. [L. naevus, mole (nevus), + G. eidos, resemblance]

nevoxanthoendothelioma
nevoxanthoendothelioma (ne′vo-zan′tho-en′do-the-le-o′ma)

SYN: juvenile xanthogranuloma. [nevus + G. xanthos, yellow, + endothelioma]

nevus
nevus, pl .nevi (ne′vus, -vi)

1. A circumscribed malformation of the skin, especially if colored by hyperpigmentation or increased vascularity; a n. may be predominantly epidermal, adnexal, melanocytic, vascular, or mesodermal, or a compound overgrowth of these tissues. 2. A benign localized overgrowth of melanin-forming cells of the skin present at birth or appearing early in life. SYN: mole (1) . [L. naevus, mole, birthmark]
acquired n. a melanocytic n. that is not visible at birth, but appears in childhood or adult life.
n. anemicus a functional developmental defect in vascular filling characterized by pale, round or oval, flat lesions, indistinguishable from surrounding normal skin on diascopy.
n. araneus SYN: spider angioma.
balloon cell n. a n. in which many of the cells are large, with clear cytoplasm.
basal cell n. [MIM*109400] a hereditary disease noted in infancy or adolescence, characterized by lesions of the eyelids, nose, cheeks, neck, and axillae, appearing as uneroded flesh-colored papules, some becoming pedunculated, and histologically indistinguishable from basal cell epithelioma; also noted are punctate keratotic lesions of the palms and soles; the lesions usually remain benign, but in some cases ulceration and invasion occur and are evidence of malignant change; autosomal dominant inheritance; caused by mutation in the human PTCH, the homolog of the “patched gene” of Drosophila. PTCH is found on chromosome 9q22.
bathing trunk n. a large hairy congenital pigmented n. with a predilection for the entire lower trunk; malignant melanoma may develop in childhood. SYN: giant pigmented n..
Becker n. a n. first seen as an irregular pigmentation of the shoulders, upper chest, or scapular area, gradually enlarging irregularly and becoming thickened and hairy. SYN: pigmented hair epidermal n..
blue n. a dark blue or blue-black n. covered by smooth skin and formed by heavily pigmented spindle-shaped or dendritic melanocytes in the reticular dermis.
blue rubber-bleb nevi a syndrome characterized by erectile, easily compressible, thin-walled hemangiomatous nodules, present at birth, widely distributed in the skin and the alimentary canal and sometimes in other tissues; lesions in the gut may perforate or cause hemorrhage, and the patient may be anemic from continual bleeding.
capillary n. capillary hemangioma of the skin.
n. cavernosus SYN: cavernous angioma.
cellular blue n. a large, acquired blue n. in which melanocytes are often clear and large, alternating with pigmented spindle cells and which may expand deeply into the subcutis; malignant change is very rare.
n. comedonicus congenital or childhood linear keratinous cystic invaginations of the epidermis, with failure of development of normal pilosebaceous follicles.
compound n. a n. in which there are nests of melanocytes in the epidermal-dermal junction and in the dermis.
congenital n. a melanocytic n. that is visible at birth, is often larger than an acquired n., and more frequently involves deeper structures. Congenital n. larger than 20.0 cm in diameter, termed giant congenital nevi, have a 6–12% lifetime risk of developing melanoma. SEE ALSO: bathing trunk n..
dysplastic n. a n. exceeding 5 mm in diameter, with irregular, indistinct, or notched borders and mixed tan-to-black and pink-to-red color. Microscopically these are basally nested and scattered intraepidermal melanocytes with hyperchromatic nuclei larger than those of basal keratinocytes. If multiple and associated with a family history of melanoma, these nevi have a high risk of malignant change, but isolated dysplastic nevi in the absence of a family history of melanoma are less frequently premalignant. SEE ALSO: malignant mole syndrome. See dysplastic n. syndrome.
epithelioid cell n. SYN: Spitz n..
faun tail n. a circumscribed growth of hair of the lumbosacral area, associated with diastematomyelia.
n. flammeus, flame n. a large congenital vascular malformation n. having a purplish color; it is usually found on the head and neck and persists throughout life. SEE ALSO: Sturge-Weber syndrome. SYN: port-wine stain.
giant pigmented n. SYN: bathing trunk n..
halo n. a benign, sometimes multiple, melanocytic n. in which involution occurs with a central brown mole surrounded by a uniformly depigmented zone or halo. SYN: leukoderma acquisitum centrifugum, Sutton n..
inflammatory linear verrucous epidermal n. rare pruritic confluent scaly erythematous papules in linear array, usually appearing in early childhood on a limb and resolving before adulthood.
intradermal n. a n. in which nests of melanocytes are found in the dermis, but not at the epidermal-dermal junction; benign pigmented nevi in adults are most commonly intradermal.
Ito n. pigmentation of skin innervated by lateral branches of the supraclavicular nerve and the lateral cutaneous nerve of the arm, due to scattered, heavily pigmented, dendritic melanocytes in the dermis.
Jadassohn n. SYN: n. sebaceus.
junction n. a n. consisting of nests of melanocytes in the basal cell zone, at the junction of the epidermis and dermis, appearing as a slightly raised, small, flat, nonhairy pigmented (brown or black) tumor.
linear epidermal n. SYN: n. unius lateris.
n. lymphaticus a cutaneous lymphangioma.
nape n. a pale vascular birthmark found on the nape of the neck in 25–50% of normal persons.
oral epithelial n. SYN: white sponge n..
Ota n. SYN: oculodermal melanosis.
n. papillomatosus a prominent wartlike mole.
pigmented hair epidermal n. SYN: Becker n..
n. pigmentosus a benign pigmented melanocytic proliferation; raised or level with the skin, present at birth or arising early in life. SYN: mole (2) .
n. pilosus a mole covered with an abundant growth of hair. SYN: hairy mole.
n. sebaceus congenital papillary acanthosis of the epidermis, with hyperplasia of sebaceous glands developing at puberty and presence of apocrine glands in nonapocrine areas of the skin (commonly the scalp). A variety of epithelial tumors may arise from a n. sebaceus in adult life, most commonly basal cell carcinoma. SYN: Jadassohn n..
spider n. SYN: spider angioma.
n. spilus a form of (flat) n. pigmentosus. SYN: spilus.
spindle cell n. SYN: Spitz n..
Spitz n. a benign, slightly pigmented or red superficial small skin tumor composed of spindle-shaped, epithelioid, and multinucleated cells that may appear atypical; most common in children, but also appearing in adults. SYN: benign juvenile melanoma, epithelioid cell n., spindle cell n..
strawberry n. a small n. vascularis (capillary hemangioma) resembling a strawberry in size, shape, and color; it usually disappears spontaneously in early childhood. See capillary hemangioma. SYN: strawberry birthmark.
Sutton n. SYN: halo n..
n. unius lateris a congenital systematized linear n. limited to one side of the body or to portions of the extremities on one side; lesions are often extensive, forming wave-like bands on the trunk and spiraling streaks on the extremities. SYN: linear epidermal n..
Unna n. capillary stain on nape of neck; persistent form of n. flammeus nuchae. SYN: erythema nuchae.
n. vascularis, n. vasculosus SYN: capillary hemangioma.
n. venosus a n. formed of a patch of dilated venules.
verrucous n. a skin-colored or darker wartlike, often linear lesion appearing at birth or early in childhood and occurring in various sizes and locations, single or multiple.
white sponge n. [MIM*193900] an autosomal dominant condition of the oral cavity characterized by soft, white or opalescent, thickened, and corrugated folds of mucous membrane; other mucosal sites are occasionally involved simultaneously; caused by mutation in either the mucosal keratin gene K4 on chromosome 12 or keratin-13 gene on 17. SYN: familial white folded dysplasia, oral epithelial n..
woolly hair n. [MIM*194300] a circumscribed patch of fine, curly hair in an otherwise normal scalp appearing during childhood and enlarging for a period of 2–3 years; autosomal dominant inheritance. There is another, mostly sporadic form that may be autosomal recessive [MIM*278150].

newberyite
newberyite (noo′ber-e-it)

The trihydrate of magnesium hydrogen phosphate; found in some renal calculi. Cf.:bobierrite, struvite. [J. Cosmo Newberry, Australian mineralogist, + -ite]

newborn
newborn (noo′born)

SYN: neonatal, neonate.

Newcomer fixative
Newcomer fixative

See under fixative.

Newton
Newton

Sir Isaac, English physicist, 1642–1727. See n., newtonian aberration, Newtonian constant of gravitation, newtonian flow, newtonian viscosity, N. disk, N. law.

newton
newton (N) (noo′ton)

Derived unit of force in the SI system, expressed as meters-kilograms per second squared (m&chmpnt;kg s⁻²); equivalent to 10⁵ dynes in the CGS system. [I. N.]

newton-meter
newton-meter

A unit of the MKS system, expressed as energy expended, or work done, by a force of 1 N acting through a distance of 1 m; equal to 1 J = 10⁷ ergs.

nexins
nexins (neks′inz)

Proteins that bridge adjacent microtubule doublets of the axoneme of cilia and flagella. [L. nexus, a binding, fr. necto, to bind + -in]

nexus
nexus, pl .nexus (nek′sus)

SYN: gap junction. [L. interconnection]

Nezelof
Nezelof

C., French pathologist, *1922. See N. syndrome, N. type of thymic alymphoplasia.

NF
NF

Abbreviation for National Formulary.

ng
ng

Abbreviation for nanogram.

NGF
NGF

Abbreviation for nerve growth factor.

NHL
NHL

Abbreviation for non-Hodgkin lymphoma.

N.H.S.
N.H.S.

Abbreviation for National Health Service (England).

NH2-terminal
NH₂-terminal

SYN: amino-terminal.

Ni
Ni

Symbol for nickel.

niacin
niacin (ni′a-sin)

SYN: nicotinic acid.

niacinamide
niacinamide (ni′a-sin-am′id)

SYN: nicotinamide.

nialamide
nialamide (ni-al′a-mid)

A monoamine oxidase inhibitor used in the treatment of depressive disorders.

nib
nib

In dentistry, the portion of a condensing instrument that comes into contact with the restorative material being condensed; its end, the face, is smooth or serrated.

nicardipine
nicardipine (ni-kar′de-pen)

A calcium channel blocker of the dihydropyridine series; used as an antihypertensive and antianginal agent.

niche
niche (nitch, nesh)

1. In contrast radiography, an eroded or ulcerated area, especially gastrointestinal or vascular, which can be detected when it fills with contrast medium. 2. An ecologic term for the position occupied by a species in a biotic community, particularly its relationships to various other competitor, predator, prey, and parasite species. [Fr.]
enamel n. SYN: enamel crypt.
Haudek n. an archaic term for the radiographic appearance in profile of contrast material filling a gastric ulcer in the wall of the stomach.

nick
nick (nik)

In molecular biology, a hydrolytic cleavage of a phosphodiester bond in one strand of a double-stranded polynucleic acid. Cf.:cut.

nickel
nickel (Ni) (nik′l)

A metallic bioelement, atomic no. 28, atomic wt. 58.6934, closely resembling cobalt and often associated with it. Protects ribosome structure against heat denaturation. A deficiency of n. causes changes in the ultrastructure of the liver. It is a cofactor in a number of enzymes ( e.g., urease). [abbrev. fr. Ger. kupfer-n., name of copper-colored ore from which n. was first obtained; n., the Ger. word for a dwarfish imp]
Raney n. See Raney N..

nickeloplasmin
nickeloplasmin (nik′l-o-plas-men)

A nickel-containing protein found in human sera.

Nickerson-Kveim test
Nickerson-Kveim test

See under test.

nicking
nicking (nik′ing)

Localized constrictions in retinal blood vessels.
arteriovenous n. constriction of a retinal vein at an artery-vein crossing.

niclosamide
niclosamide (ni-klo′sa-mid)

A teniacide effective against intestinal cestodes.

nicofuranose
nicofuranose (ni-ko-fu′ra-nos)

A peripheral vasodilator.

Nicol
Nicol

William, Scottish physicist, 1768–1851. See N. prism.

Nicolas
Nicolas

Joseph, French physician, *1878. See N.-Favre disease.

Nicolle
Nicolle

Charles J.H., French microbiologist and Nobel laureate, 1866–1936. See N. stain for capsules.

nicotinamide
nicotinamide (nik-o-tin′a-mid)

The biologically active amide of nicotinic acid, used in the prevention and treatment of pellagra. SYN: niacinamide, nicotinic acid amide.

nicotinamide adenine dinucleotide
nicotinamide adenine dinucleotide (NAD, NAD⁺, NADH)

Ribosylnicotinamide 5′-phosphate (NMN) and adenosine 5′-phosphate (AMP) linked by phosphoanhydride linkage between the two phosphoric groups; binds as a coenzyme to proteins, serves in respiratory metabolism (hydrogen acceptor and donor) through alternate oxidation and reduction (NAD⁺ &rrl; NADH). See also entries under NAD⁺ and NADP⁺.

nicotinamide adenine dinucleotide phosphate
nicotinamide adenine dinucleotide phosphate (NADP, NADP⁺, NADPH)

A coenzyme of many oxidases (dehydrogenases), in which the reaction NADP⁺ + 2H &rrl; NADPH + H⁺ takes place; the third phosphoric group esterifies the 2′-hydroxyl of the adenosine moiety of NAD⁺.

nicotinamide mononucleotide
nicotinamide mononucleotide (NMN)

A condensation product of nicotinamide and ribose 5-phosphate, linking the N of nicotinamide to the (β) C-1 of the ribose; in NAD⁺, the ring is linked by the 5′-phosphoryl residue of the ribose moiety to the 5′-phosphoryl residue of AMP; a precursor in the synthesis of NAD⁺.

nicotinate
nicotinate (nik′o-ti-nat)

Salt or ester of nicotinic acid; some nicotinates are used in ointments as rubefacients.

nicotine nicotine (nik′o-ten)

1-Methyl-2-(3-pyridyl)pyrrolidine;a poisonous volatile alkaloid derived from tobacco (Nicotiana spp.) and responsible for many of the effects of tobacco; it first stimulates (small doses), then depresses (large doses) at autonomic ganglia and myoneural junctions; its principal urinary metabolite is cotinine. N. is an important tool in physiologic and pharmacologic investigation, is used as an insecticide and fumigant, and forms salts with most acids. SEE ALSO: tobacco. [Nicotiana, genus name of botanical source, + - ine] N. in inhaled tobacco smoke or in smokeless tobacco applied to buccal or nasal mucosa enters the circulation within seconds, causing an increase in heart rate, ventricular stroke volume, and myocardial oxygen consumption, as well as euphoria, heightened alertness, and a sense of relaxation. N. use is powerfully addictive, readily leading to habituation, tolerance, and dependency. Withdrawal from n. causes restlessness, irritability, anxiety, difficulty concentrating, and craving for n.. Addiction to n. is the reason for most tobacco use and is thus directly responsible for the resulting morbidity and mortality.

nicotinehydroxamic acid methiodide
nicotinehydroxamic acid methiodide (nik′o-ten-hi′drok-sam′ik as′id me-thi′o-did)

An effective cholinesterase reactivator, with actions that are most marked at the skeletal neuromuscular junction; antidotal effects are less striking at autonomic effector sites and insignificant in the central nervous system.

nicotinic
nicotinic (nik-o-tin′ik)

Relating to the stimulating action of acetylcholine and other nicotine-like agents on autonomic ganglia, adrenal medulla, and the motor end-plate of striated muscle.

nicotinic acid
nicotinic acid

Pyridine-3-carboxylic acid;a part of the vitamin B complex; used in the prevention and treatment of pellagra, as a vasodilator, and in hyperlipidemia, where it lowers cholesterol and acts as an HDL-raising agent. SYN: anti–black-tongue factor, antipellagra factor, niacin, pellagra-preventing factor, vitamin PP.

nicotinic acid amide
nicotinic acid amide

SYN: nicotinamide.

nicotinic alcohol
nicotinic alcohol

SYN: nicotinyl alcohol.

nicotinomimetic
nicotinomimetic (nik-o-tin′o-mi-met′ik)

Mimicking the action of nicotine.

nicotinyl alcohol
nicotinyl alcohol (nik-o-tin′il)

Same action and use as nicotinyl tartrate. SYN: nicotinic alcohol.

nicotinyl tartrate
nicotinyl tartrate

A relatively weak peripheral vasodilator related to nicotinic acid; used in peripheral vascular disorders such as Raynaud disease, acrocyanosis, and chilblains.

nicoumalone
nicoumalone (ni-koo′ma-lon)

SYN: acenocoumarol.

nictation
nictation (nik-ta′shun)

SYN: nictitation.

nictitate
nictitate (nik′ti-tat)

To wink. [see nictitation]

nictitation
nictitation (nik-ti-ta′shun)

Winking. SYN: nictation. [L. nicto, pp. -atus, to wink, fr. nico, to beckon]

nidal
nidal (ni′dal)

Relating to a nidus, or nest.

nidation
nidation (ni-da′shun)

Embedding of the early embryo in the uterine endometrium. [L. nidus, nest]

NIDDM
NIDDM

Abbreviation for non-insulin-dependent diabetes mellitus.

nidogen
nidogen (ni′do-jen)

SYN: entactin. [L. nidus, nest, + -gen 1.]

nidus
nidus, pl .nidi (ni′dus, ni′di)

1. A nest. 2. The nucleus or central point of origin of a nerve. 3. A focus of infection. 4. The nucleus of a crystal; the coalescence of molecules or small particles that is the beginning of a crystal or similar solid deposit. 5. The focus of reduced density at the center of an osteoid osteoma, on bone radiographs. [L. nest]
n. avis a deep depression on each side of the inferior surface of the cerebellum, between the uvula and the biventral lobe, in which the tonsil rests. SYN: n. hirundinis. [L. bird's nest]
n. hirundinis SYN: n. avis. [L. swallow's nest]

Niemann
Niemann

Albert, German physician, 1880–1921. See N.-Pick cell, N.-Pick disease, N. disease, N. splenomegaly.

Niewenglowski
Niewenglowski

Gaston H., 19th century French scientist. See N. rays, under ray.

nifedipine
nifedipine (ni-fed′i-pen)

A calcium channel-blocking agent of the dihydropyridine type; coronary vasodilator.

nifenazone
nifenazone (ni-fen′a-zon)

An analgesic and antipyretic.

nifuraldezone
nifuraldezone (ni-fur-al′de-zon)

An antibacterial agent.

nifuratel
nifuratel (ni-fu′ra-tel)

trichomonacide.

nifuroxime
nifuroxime (ni-fu-rok′sem, -sim)

A furan derivative, principally effective against Candida albicans.

nigerose
nigerose (ni′je-ros)

A disaccharide obtained by the hydrolysis of amylopectins, consisting of two d-glucose residues bound in an α1–3 linkage. [fr. nigeran, a polysaccharide synthesized by Aspergillus niger]

nightguard
nightguard (nit′gard)

A device used to stabilize the teeth and reduce the traumatic effects of bruxism.

Nightingale
Nightingale

Florence, 1820-1910. English nurse; founder of modern nursing.

nightmare
nightmare (nit′mar)

A terrifying dream, as in which one is unable to cry for help or to escape from a seemingly impending evil. SEE ALSO: incubus, succubus. [A.S. nyht, night, + mara, a demon]

nightshade
nightshade (nit′shad)

Any of a number of plants of the genus Solanum (family Solanaceae) and of some other genera of the family Solanaceae.
deadly n. SYN: belladonna.

night terrors
night terrors (nit′tar-erz)

A disorder occurring in children, in which the child awakes screaming with fright, the distress persisting for a time during a state of semiconsciousness. SYN: pavor nocturnus, sleep terror.

nigra
nigra (ni′gra)

In neuroanatomy, the substantia n.. [L. fr. niger, black]

nigrities
nigrities (ni-grish′i-ez)

A black pigmentation. [L. blackness, fr. niger, black]
n. linguae SYN: black tongue.

nigrosin
nigrosin, nigrosine (ni′gro-sin, -sen) [C.I. 50420]

A variable mixture of blue-black aniline dyes; used as a histologic stain for nervous tissue and as a negative stain for studying bacteria and spirochetes; also used to discriminate between live and dead cells in dye-exclusion staining.

Nigrospora
Nigrospora (ni-gros′por-a)

A genus of rapidly growing fungi that produces shiny, black conidia in cultures; it is a common contaminant in laboratory cultures and is nonpathogenic for humans.

nigrostriatal
nigrostriatal (ni′gro-stri-a′tal)

Referring to the efferent connection of the substantia nigra with the striatum. See substantia nigra.

NIH
NIH

Abbreviation for National Institutes of Health (U.S. Public Health Service).

nihilism
nihilism (ni′i-lizm, ni′hi-lizm)

1. In psychiatry, the delusion of the nonexistence of everything, especially of the self or part of the self. 2. Engagement in acts that are totally destructive to one's own purposes and those of one's group. [L. nihil, nothing]
therapeutic n. a disbelief in the efficacy or value of therapy, as of drugs, psychotherapy, etc.

nikethamide
nikethamide (ni-keth′a-mid)

Drug that acts mainly on the central nervous system, as a respiratory and cardiovascular stimulant.

Nikiforoff
Nikiforoff

Mikhail, Russian dermatologist, 1858–1915. See N. method.

Nikolsky
Nikolsky

Pyotr V., Russian dermatologist, 1858–1940. See N. sign.

Nile blue A
Nile blue A [C.I. 51180]

A basic oxazin dye, used as a fat and vital stain, and in Kittrich stain; as an indicator, it changes from blue to purplish red at pH 10–11.

nimodipine
nimodipine (ni-mo′di-pen)

A calcium channel blocking drug of the dihydropyridine series used as a vasodilator.

nimustine
nimustine (ni′mus-tin)

A nitrosourea antineoplastic similar to carmustine (BCNU)

ninhydrin
ninhydrin (nin-hi′drin)

Reacts with free amino acids to yield CO₂, NH₃, and an aldehyde, the NH₃ produced yielding a colored product (diketohydrindylidene-diketohydrinamine, a bi-indanedione derivative). SEE ALSO: n. reaction.

niobium
niobium (Nb) (ni-o′be-um)

A rare metallic element, atomic no. 41, atomic wt. 92.90638, usually found with tantalum. [Niobe, daughter of Tantalus]

nipple
nipple (nip′l) [TA]

A wartlike projection at the apex of the breast on the surface of which the lactiferous ducts open; it is surrounded by a circular pigmented area, the areola. SYN: papilla mammae [TA] , mammilla (2) , papilla of breast, teat (1) , thele, thelium (3) . [dim. of A.S. neb, beak, nose (?)]
accessory n. a supernumerary n. occurring on the mammary line.
aortic n. colloquial term for the radiographic appearance of the left superior intercostal or accessory hemiazygos vein as a bump on the aortic knob.

niridazole
niridazole (ni-rid′a-zol)

Used for the treatment of schistosomiasis, amebiasis, and dracontiasis.

nisin
nisin (ni′sin)

A polypeptide antibiotic produced by Streptococcus lactis; active against certain streptococci, Mycobacterium tuberculosis, Clostridium difficile, and other bacteria.

nisoldipine
nisoldipine (ni-sol′di-pen)

A calcium channel blocker of the dihydropyridine series; used as an antihypertensive and antianginal agent.

Nissen
Nissen

Rudolf, Swiss surgeon, 1896–1981. See Collis-N. fundoplication, N. fundoplication, N. operation.

Nissl
Nissl

Franz, German neurologist, 1860–1919. See N. bodies, under body, N. degeneration, N. granules, under granule, N. substance, N. stain.

nit
nit (nit)

1. The ovum or hatched egg of a body, head, or crab louse; the egg is attached to human hair or clothing by a layer of chitin. 2. A unit of luminance; a luminous intensity of 1 candela per square meter of orthogonally projected surface. [A.S. knitu]

Nitabuch
Nitabuch

Raissa, 19th century German physician. See N. layer, N. membrane, N. stria.

niter
niter (ni′ter)

SYN: potassium nitrate. [G. nitron, soda, formerly not distinguished from potash]
cubic n. SYN: sodium nitrate.

niton
niton (ni′ton)

Archaic term for radon.

nitrate
nitrate (ni′trat)

A salt of nitric acid.

nitrazepam
nitrazepam (ni-tra′ze-pam)

A hypnotic and sedative of the benzodiazepine class.

nitrendipine
nitrendipine (ni-tren′-di-pen)

A calcium channel blocker of the dihydropyridine series; used as an antihypertensive.

nitric acid
nitric acid (ni′trik)

A strong acid oxidant and corrosive.
fuming n. contains about 91% n.; used as a caustic.

nitric oxide nitric oxide (NO&chmpnt;)

A colorless, radical-free gas that reacts rapidly with O₂ to form other nitrogen oxides (e.g., NO₂, N₂O₃, and N₂O₄) and ultimately is converted to nitrite (NO₂⁻) and nitrate (NO₃⁻); a gaseous mediator of cell-to-cell communication and potent vasodilator, formed from l-arginine in bone, brain, endothelium, granulocytes, pancreatic beta cells, and peripheral nerves by a constitutive n. synthase, and in hepatocytes, Kupffer cells, macrophages, and smooth muscle by an inducible n. synthase (e.g., induced by endotoxin). NO&chmpnt; activates soluble guanylate cyclase, mediates penile erection, and may be the first known retrograde neurotransmitter.The short-lived NO&chmpnt; molecule is a product of various tissues and plays a role in various processes. NO&chmpnt; elaborated by endothelium, which is identical to endothelium-derived relaxing factor, dilates vessels by relaxing vascular smooth muscle; nitrites used in coronary and peripheral vascular disease induce or mimic this action. The 1998 Nobel Prize in Medicine or Physiology was awarded to 3 U.S. pharmacologists, Robert F. Furchgott, Ferid Murad, and Louis J. Ignarro, for their independent discoveries of the role of n. in cardiovascular physiology. In the immune system, macrophages use NO&chmpnt; as a cytotoxic agent. Deficiency or inactivation of NO&chmpnt; may contribute to the pathogenesis of both hypertension and atherosclerosis. An excess of NO&chmpnt;, which is a free radical, is toxic to brain cells, and NO&chmpnt; is also responsible for the precipitate, often fatal, drop in blood pressure accompanying septic shock. Free NO&chmpnt; in the bloodstream is rapidly reduced by the iron of hemoglobin.
n. reductase an enzyme oxidizing N₂ with some acceptor to 2NO&chmpnt;, a first step in the fixing of atmospheric nitrogen by bacteria.
n. synthase (NO synthase) an enzyme that catalyzes the reaction of l-arginine with 2O₂ and 1.5NADPH to form NO, l-citrulline, 1.5NADP⁺, and 2H₂O; there are an inducible and two constitutive forms of this enzyme: the constitutive forms play significant roles in regulating vascular tone, tissue blood flow, renal function, etc.; in bone, brain, endothelium, granulocytes, pancreatic Z-cells, and peripheral nerves, the constitutive forms are calcium-calmodulin dependent; in brain, the enzyme is cytosolic; in endothelium, it is membrane bound; the inducible form of the enzyme ( e.g., by endotoxin) in hepatocytes, Kupffer cells, macrophages, and smooth muscle is not calmodulin dependent.

nitridation
nitridation (ni-tri-da′shun)

Formation of nitrides; formation of nitrogen compounds through the action of ammonia (analogous to oxidation).

nitride
nitride (ni′trid)

A compound of nitrogen and one other element, e.g., magnesium n., Mg₃N₂.

nitrification
nitrification (ni′tri-fi-ka′shun)

1. Bacterial conversion of nitrogenous matter into nitrates. 2. Treatment of a material with nitric acid.

nitrile
nitrile (ni′tril)

An alkyl cyanide. Individual nitriles are named for the acid formed on hydrolysis; e.g., CH₃CN is acetonitrile rather than methyl cyanide.

nitrilo- nitrilo-

Prefix indicating a tervalent nitrogen atom attached to three identical groups; e.g., nitrilotriacetic acid, N(CH₂COOH)₃.

nitrimuriatic acid
nitrimuriatic acid (ni′tri-mu-re-at′ik)

SYN: nitrohydrochloric acid.

nitrite
nitrite (ni′trit)

A salt of nitrous acid.

nitrituria
nitrituria (ni-tri-too′re-a)

The presence of nitrites in the urine, as a result of the action of Escherichia coli, Proteus vulgaris, and other microorganisms that may reduce nitrates.

nitro- nitro-

Prefix denoting the group –NO₂. [G. nitron, sodium carbonate.]

nitrocellulose
nitrocellulose (ni-tro-sel′u-los)

SYN: pyroxylin.

nitrochloroform
nitrochloroform (ni-tro-klor′o-form)

SYN: chloropicrin.

nitrofurans
nitrofurans (ni-tro-fu′ranz)

Antimicrobials ( e.g., nitrofurazone) effective against Gram-positive and Gram-negative organisms.

nitrofurantoin
nitrofurantoin (ni′tro-fu-ran′to-in)

A urinary antibacterial agent with a wide range of activity against both Gram-positive and Gram-negative organisms; also available as n. sodium for injection.

nitrofurazone
nitrofurazone (ni-tro-fu′ra-zon)

A topical bacteriostatic and bactericidal agent often used in burns.

nitrogen
nitrogen (N) (ni′tro-jen)

1. A gaseous element, atomic no. 7, atomic wt. 14.00674; N₂ forms about 78.084% by volume of the dry atmosphere. 2. The molecular form of n., N₂. 3. Pharmaceutical grade N₂, containing not less than 99.0% by volume of N₂; used as a diluent for medicinal gases, and for air replacement in pharmaceutical preparations. [L. nitrum, niter, + -gen, to produce]
blood urea n. (BUN) n., in the form of urea, in the blood; the most prevalent of nonprotein nitrogenous compounds in blood; blood normally contains 10–15 mg of urea/100 mL. Measurements in the laboratory are commonly used as a measure of renal function. SEE ALSO: urea n..
filtrate n. nonprotein n. in various compounds that normally pass through the glomerular filtration or through a filter in the laboratory (after proteins are precipitated).
heavy n. SYN: n.-15.
n. monoxide SYN: nitrous oxide.
nonprotein n. (NPN) the n. content of other than protein bodies; e.g., about one-half the nonprotein n. in the blood is contained in urea. SYN: rest n..
rest n. SYN: nonprotein n..
undetermined n. the n. of blood, urine, etc., other than urea, uric acid, amino acids, etc., that can be directly estimated; in blood it amounts to about 25 mg/100 mL.
urea n. the portion of n. in a biologic sample, such as blood or urine, that derives from its content of urea. SEE ALSO: blood urea n..
urinary n. n. excreted as urea, amino acids, uric acid, etc., in the urine; 1 g of urinary n. indicates the breakdown in the body of 6.25 g of protein. SEE ALSO: n. equivalent.

nitrogen-13
nitrogen-13 (¹³N)

A cyclotron-produced, positron-emitting radioisotope of nitrogen with a half-life of 9.97 minutes; used in protein metabolism studies and in positron-emission tomography.

nitrogen-14
nitrogen-14 (¹⁴N)

The common nitrogen isotope, making up 99.63% of natural nitrogen.

nitrogen-15
nitrogen-15 (¹⁵N)

The less common stable nitrogen isotope, making up 0.37% of natural nitrogen. SYN: heavy nitrogen.

nitrogenase
nitrogenase (ni′tro-je-nas)

Formerly a general term used to describe enzyme systems that catalyze the reduction of molecular nitrogen to ammonia in nitrogen-fixing bacteria; now specifically applied to enzymes that carry out this reaction with reduced ferredoxin and ATP; typically n. consists of two components, the first of which reduces N₂ while the second transfers electrons.

nitrogen distribution
nitrogen distribution

SYN: nitrogen partition.

nitrogen group
nitrogen group

Five trivalent or quinquivalent elements whose hydrogen compounds are basic and whose oxyacids vary from monobasic to tetrabasic: nitrogen, phosphorus, arsenic, antimony, and bismuth.

nitrogen lag
nitrogen lag

The length of time after the ingestion of a given protein before the amount of nitrogen equal to that in the protein has been excreted in the urine.

nitrogenous
nitrogenous (ni-troj′e-nus)

Relating to or containing nitrogen.

nitrogen partition
nitrogen partition

Determination of the distribution of nitrogen in the urine among the various constituents. SYN: nitrogen distribution.

nitroglycerin
nitroglycerin (ni-tro-glis′er-in)

An explosive yellowish oily fluid formed by the action of sulfuric and nitric acids on glycerin; used as a vasodilator, especially in angina pectoris; generates nitric oxide. SYN: glyceryl trinitrate, trinitroglycerin.

nitrohydrochloric acid
nitrohydrochloric acid (ni′tro-hi-dro-klor′ik)

An extremely caustic mixture that contains 18 parts nitric acid and 82 parts hydrochloric acid. SYN: aqua regia, aqua regalis, nitrimuriatic acid.

nitromannitol
nitromannitol (ni-tro-man′i-tol)

SYN: mannitol hexanitrate.

nitromersol
nitromersol (ni-tro-mer′sol)

The anhydride of 4-nitro-3-hydroxymercuriorthocresol; a synthetic organic mercurial compound, used as an antiseptic for skin and mucous membranes.

nitrometer
nitrometer (ni-trom′e-ter)

A device for collecting and measuring the nitrogen set free in a chemical reaction. [nitrogen + G. metron, measure]

nitron
nitron (ni′tron)

A reagent for the determination of nitric acid, perchlorate, and rhenium, as it is one of the few substances to form an insoluble nitrate.

nitrophenylsulfenyl
nitrophenylsulfenyl (Nps) (ni′tro-fen′il-sul-fen′il)

O₂N–C₆H₄–S–; nitrophenylthio;a radical easily attached to amino groups; used in peptide synthesis and protein chemistry.

nitroprusside
nitroprusside (ni-tro-prus′id)

The anion [Fe(CN)₅NO]^&dbond;; as in sodium n.; used as a vasodilator by the intravenous route.

nitrosamines
nitrosamines (ni-tros′am-enz)

Amines substituted by a nitroso (NO) group, usually on a nitrogen atom, to yield N-n. (R–NH–NO or R₂N–NO); can be formed by direct combination of an amine and nitrous acid (can be formed from nitrites in the acidic gastric juice); some are mutagenic and/or carcinogenic.

nitroso- nitroso-

Prefix denoting a compound containing nitrosyl. [L. nitrosus]

nitrosourea
nitrosourea (ni-tro′so-oor′e-a)

Alkylating agent used in the treatment of many neoplasms; an example is BCNU [N,N′-bis(2-chloroethyl)-N-n.; carmustine].

nitrosyl
nitrosyl (ni′tro-sil)

A univalent radical or atom group, –N&dbond;O, forming the nitroso compounds.

nitrous
nitrous (ni′trus)

Denoting a nitrogen compound containing one less atom of oxygen than the nitric compounds; one in which the nitrogen is present in its trivalent state.

nitrous acid
nitrous acid

HNO₂;a standard biologic and clinical laboratory reagent.

nitrous oxide
nitrous oxide

N₂O;a nonflammable, nonexplosive gas that will support combustion; widely used as a rapidly acting, rapidly reversible, nondepressant, and nontoxic inhalation analgesic to supplement other anesthetics and analgesics; its anesthetic potency alone is inadequate to provide surgical anesthesia. SYN: dinitrogen monoxide, nitrogen monoxide.

nitroxanthic acid
nitroxanthic acid (ni-tro-zan′thik)

SYN: picric acid.

nitroxoline
nitroxoline (ni-trok′so-len)

An antibacterial agent.

nitroxy
nitroxy (ni-trok′se)

The –O–NO₂ radical. [contraction of nitryloxy]

nitroxyl
nitroxyl (ni-trok′sil)

The nitrosyl hydride, HNO.

nitryl
nitryl (ni′tril)

The radical –NO₂ of the nitro compounds.

nizatidine
nizatidine (ni-zat′i-den)

A histamine H₂ antagonist used to treat active duodenal ulcers.

njovera
njovera (nyo-ver′a)

A nonvenereal disease of children in Zimbabwe, indistinguishable from syphilis, due to an organism apparently identical with Treponema pallidum; probably the same as bejel. [Zimbabwean]

N.K.
N.K.

Abbreviation for Nomenklatur Kommission.

nkat
nkat

Abbreviation for nanokatal.

Nle
Nle

Abbreviation for norleucine.

NLN
NLN

Abbreviation for National League for Nursing.

nM
nM

Abbreviation for nanomolar.

nm
nm

Abbreviation for nanometer.

NMDA
NMDA

Abbreviation for N-methyl d-aspartate; excitotoxic amino acid used to identify a specific subset of glutamate (an excitatory amino acid) receptors. SYN: N-methyl d-aspartic acid.

NMN
NMN

Abbreviation for nicotinamide mononucleotide.

NMP
NMP

Abbreviation for nucleoside 5′-monophosphate.

NMR
NMR

Abbreviation for nuclear magnetic resonance.

NO&chmpnt;
NO&chmpnt;

Symbol for nitric oxide.

No
No

Symbol for nobelium.

Noack
Noack

M., 20th century German physician. See N. syndrome.

nobelium
nobelium (No) (no-bel′e-um)

An unstable transuranium element, atomic no. 102, prepared by bombardment of curium with carbon-12 nuclei and similar heavy ions on other elements of the transuranium series. [Nobel Institute for Physics and A.B. Nobel, Swedish inventor, 1833–1896]

Noble
Noble

Charles P., U.S. gynecologist, 1863–1935. See N. position.

Noble
Noble

Robert L., Canadian physiologist, *1910. See N.-Collip procedure.

Noble stain
Noble stain

See under stain.

Nocard
Nocard

Edmund I.E., French veterinarian, 1850–1903. See Nocardia, Nocardiaceae.

Nocardia
Nocardia (no-kar′de-a)

A genus of aerobic actinomycetes (family Nocardiaceae, order Actinomycetales), higher bacteria, containing weakly acid-fast, slender rods or filaments, frequently swollen and occasionally branched, forming a mycelium. Coccus or bacillary forms are produced by these organisms, which are mainly saprophytic but may be a cause of mycetoma or nocardiosis. [E. Nocard]
Nocardia asteroides a species of aerobic, Gram-positive, partially acid-fast, branching organisms causing nocardiosis and possibly mycetoma in humans.
Nocardia brasiliensis a bacterial species that closely resembles Nocardia asteroides and is a cause of mycetoma and nocardiosis in humans.
Nocardia caviae former name for Nocardia otitidiscaviarum.
Nocardia farcinica a species causing bovine farcy; it is the type species of the genus Nocardia.
Nocardia gibsonii SYN: Streptomyces gibsonii.
Nocardia lurida former name for Amycolatopsis orientalis lurida.
Nocardia madurae former name for Actinomadura madurae.
Nocardia mediterranei a bacterial species that produces rifamycin.
Nocardia nova a bacterial species commonly recovered from human infections.
Nocardia orientalis a bacterial species that produces vancomycin.
Nocardia otitidiscaviarum a higher bacteria (formerly Nocardia caviae) living in soil and one of the causes of nocardiosis and actinomycetoma.
Nocardia transvalensis an aerobic actinomycete; a cause of nocardiosis.

nocardia
nocardia, pl .nocardiae (no-kar′de-a, no-kar′de-e)

A vernacular term used to refer to any member of the genus N..

Nocardiaceae
Nocardiaceae (no-kar-de-a′se-e)

A family of acid-fast, Gram-positive, aerobic bacteria (order Actinomycetales) that includes the genus Nocardia. [E. Nocard]

nocardiasis
nocardiasis (no-kar-di′a-sis)

SYN: nocardiosis.

nocardioform
nocardioform (no-kar′de-o-form)

Denoting an organism that morphologically and culturally resembles members of the genus Nocardia.

Nocardiopsis
Nocardiopsis (no-kar-de-op′sis)

A genus of higher bacteria living in soil that cause subacute or chronic pneumonia, subcutaneous infection, or disseminated disease, usually in immunosuppressed patients.
N. dassonvillei an aerobic actinomycete, formerly Nocardia dassonvillei; a cause of actinomycetoma.

nocardiosis
nocardiosis (no-kar-de-o′sis)

A generalized disease in humans and other animals caused by Nocardia asteroides, N. otitidiscaviarum, N. transvalensis, and N. brasiliensis and characterized by primary pulmonary lesions that may be subclinical or chronic with hematogenous spread, to deep viscera, including the central nervous system; most commonly occurs in immunosuppressed patients. SYN: nocardiasis.
granulomatous n. a form of n. characterized by emaciation, abdominal distention, and replacement of lymphoid tissue in lymph nodes and spleen by granulomatous tissue.

nocebo
nocebo (no-se′bo)

An unpleasant effect attributable to administration of a placebo; jargon. [L. I shall harm, fr. noceo, to harm, by analogy with placebo, I shall please]

noci- noci-

Hurt, pain, injury. [L. noceo]

nociceptive
nociceptive (no-si-sep′tiv)

Capable of appreciation or transmission of pain. [see nociceptor]

nociceptor
nociceptor (no-si-sep′ter, -tor)

A peripheral nerve organ or mechanism for the reception and transmission of painful or injurious stimuli. [noci- + L. capio, to take]

nocifensor
nocifensor (no-si-fen′ser)

Denoting processes or mechanisms that act to protect the body from injury; specifically, a system of nerves in the skin and mucous membranes that react to adjacent injury by causing vasodilation. [noci- + L. fendo (only in compounds), to strike, ward off]

noct- noct-

Nocturnal. SEE ALSO: nycto-. [L. nox, night]

noctalbuminuria
noctalbuminuria (nok′tal-boo′mi-nu′re-a)

A pathologic increase of albumin in urine excreted during the evening, a rarely observed event. [L. nox, night, + albuminuria]

noctiphobia
noctiphobia (nok′te-fo′be-a)

Morbid dread of night and its darkness and silence. [noct- + phobia]

noct. maneq.
noct. maneq.

Abbreviation for L. nocte maneque, at night and in the morning.

noctograph
noctograph (nok′to-graf)

SYN: scotograph. [noct- + G. grapho, to write]

nocturia
nocturia (nok-too′re-a)

Purposeful urination at night, after waking from sleep; typically caused by increased nocturnal secretion of urine resulting from failure of suppression of urine production during recumbency or incomplete emptying of the bladder because of obstructive lesions in the lower urinary tract or detrusor instability. SYN: nycturia. [noct- + G. ouron, urine]

nocturnal
nocturnal (nok-ter′nal)

Pertaining to the hours of darkness; opposite of diurnal (1). [L. nocturnus, of the night]

nodal
nodal (no′dal)

Relating to any node.

node
node (nod) [TA]

1. A knob or nodosity; a circumscribed swelling; in anatomy, a circumscribed mass of tissue. 2. A circumscribed mass of differentiated tissue. 3. A knuckle, or finger joint. SYN: nodus [TA] . [L. nodus, a knot]
anterior tibial n. SYN: anterior tibial lymph n..
n. of Aschoff and Tawara SYN: atrioventricular n..
atrioventricular n. (AV n.) [TA] 1. a small n. of modified cardiac muscle fibers located near the ostium of the coronary sinus; it gives rise to the atrioventricular bundle of the conduction system of the heart; 2. loosely circumscribed conduction tissue with sparse pacemakerlike (P) cells in the atrioventricular junction. SYN: nodus atrioventricularis [TA] , n. of Aschoff and Tawara, Tawara n..
Babès nodes collections of lymphocytes in the central nervous system found in rabies.
buccinator n., buccal n. SYN: buccal lymph n..
n. of Cloquet SYN: proximal deep inguinal lymph n..
coronary n. the uppermost part of the atrioventricular n..
cystic n. SYN: cystic lymph n..
delphian n. a midline prelaryngeal lymph n., adjacent to the thyroid gland, enlargement of which is indicative of thyroid disease or early metastasis from the subglottic larynx.
Dürck nodes perivascular chronic inflammatory infiltrates in the brain, occurring in human trypanosomiasis.
fibular n. SYN: fibular lymph n..
Flack n. SYN: sinuatrial n..
foraminal n. SYN: lymph n. of anterior border of omental foramen.
Haygarth nodes exostoses from the margins of the articular surfaces and from the periosteum and bone in the neighborhood of the joints of the fingers, leading to ankylosis and associated with lateral deflection of the fingers toward the ulnar side, which occur in rheumatoid arthritis.
Heberden nodes exostoses about the size of a pea or smaller, found on the terminal phalanges of the fingers in osteoarthritis, which are enlargements of the tubercles at the articular extremities of the distal phalanges. SYN: tuberculum arthriticum (1) .
hemal n. a lymphoid structure in which the blood sinuses are present in place of lymph sinuses; hemal nodes occur in ruminants and some other mammals, but their presence in humans is questioned. SYN: hemal gland, hemolymph gland, hemolymph n., vascular gland.
hemolymph n. SYN: hemal n..
Hensen n. SYN: primitive n..
intermediate lacunar n. SYN: intermediate lacunar lymph n..
jugulodigastric n. SYN: jugulodigastric lymph n..
juguloomohyoid n. SYN: juguloomohyoid lymph n..
Keith n. SYN: sinuatrial n..
Keith and Flack n. SYN: sinuatrial n..
Koch n. SYN: sinuatrial n..
lateral lacunar n. SYN: lateral lacunar lymph n..
n. of ligamentum arteriosum SYN: lymph n. of ligamentum arteriosum.
lymph n. lymph n..
malar n. SYN: malar lymph n..
mandibular nodes SYN: mandibular lymph n..
medial lacunar n. SYN: medial lacunar lymph n..
middle rectal n. SYN: middle rectal lymph n..
milkers' nodes SYN: milkers' nodules, under nodule.
nasolabial n. SYN: nasolabial lymph n..
Osler n. in subacute bacterial endocarditis, circumscribed, painful erythematous swellings, ranging in size from that of a pinhead to that of a pea, in the skin and subcutaneous tissues of the hands and feet. SYN: Osler sign.
parietal nodes SYN: parietal lymph nodes, under lymph n..
posterior tibial n. SYN: posterior tibial lymph n..
primitive n. a local thickening of the blastoderm at the cephalic end of the primitive streak of the embryo. SYN: Hensen knot, Hensen n., Hubrecht protochordal knot, primitive knot, protochordal knot.
promontorial common iliac nodes [TA] nodes of the common iliac group located at the promontory of the sacrum. SYN: nodi lymphoidei iliaci communes promontorii [TA] , nodi lymphoidei promontorii.
n. of Ranvier a short interval in the myelin sheath of a nerve fiber, occurring between each two successive segments of the myelin sheath; at the n., the axon is invested only by short, finger-like cytoplasmic processes of the two neighboring Schwann cells or, in the central nervous system, oligodendroglia cells. SEE ALSO: myelin sheath.
retropyloric nodes SYN: retropyloric lymph nodes, under lymph n..
Rosenmüller n. SYN: proximal deep inguinal lymph n..
n. of Rouviere one of the lateral group of retropharyngeal lymph nodes. See retropharyngeal lymph nodes, under lymph n..
S-A n. abbreviation for sinoatrial n..
sentinel n. SYN: sentinel lymph n..
signal n. See signal lymph n..
singer's nodes SYN: vocal cord nodules, under nodule.
sinoatrial n. (S-A n.) SYN: sinuatrial n..
sinuatrial n. [TA] the mass of specialized cardiac muscle fibers that normally acts as the “pacemaker” of the cardiac conduction system; it lies under the epicardium at the upper end of the sulcus terminalis. SYN: nodus sinuatrialis [TA] , atrionector, Flack n., Keith and Flack n., Keith n., Koch n., sinoatrial n., sinus n..
sinus n. SYN: sinuatrial n..
subdigastric n. SYN: jugulodigastric lymph n..
subpyloric n. SYN: subpyloric lymph nodes, under lymph n..
suprapyloric n. SYN: suprapyloric lymph n..
Tawara n. SYN: atrioventricular n..
teacher's nodes SYN: vocal cord nodules, under nodule.
Troisier n. SYN: Troisier ganglion.
Virchow n. SYN: signal lymph n..
visceral nodes SYN: visceral lymph nodes, under lymph n..
vital n. SYN: noeud vital.

nodi
nodi (no′di)

Plural of nodus. [L.]

nodose
nodose (no′dos)

Having nodes or knotlike swellings. [L. nodosus]

nodulation
nodulation (nod-u-la′shun)

The formation or the presence of nodules.

nodule
nodule (nod′ul) [TA]

A small node; in skin, a node up to 1.0 cm in diameter, solid, with palpable depth. SYN: nodulus (1) [TA] . [L. nodulus, dim. of nodus, knot]
aggregated lymphatic nodules SYN: aggregated lymphoid nodules of small intestine.
aggregated lymphoid nodules [TA] masses of lymphoid tissue in the submucous coat of the vermiform appendix. SYN: noduli lymphoidei aggregati appendicis vermiformis [TA] , aggregated lymphatic follicles of vermiform appendix, folliculi lymphatici aggregati appendicis vermiformis.
aggregated lymphoid nodules of small intestine [TA] collections of many lymphoid follicles closely packed together, forming oblong elevations on the mucous membrane of the ileum opposite the attachment of mesentary. SYN: aggregate glands, aggregated lymphatic follicles of small intestine, aggregated lymphatic nodules, agmen peyerianum, agminate glands, agminated glands, folliculi lymphatici aggregati, Peyer glands, Peyer patches.
Albini nodules minute fibrous nodules on the margins of the mitral and tricuspid valves of the heart, sometimes present in the neonate and representing fetal tissue rests; described previously by Cruveilhier. Cf.:nodules of semilunar cusps.
apple jelly nodules descriptive term for the papular lesions of lupus vulgaris, as they appear on diascopy.
Arantius n. SYN: nodules of semilunar cusps.
Aschoff nodules SYN: Aschoff bodies, under body.
benign rheumatoid nodules SYN: pseudorheumatoid nodules.
Bianchi n. SYN: nodules of semilunar cusps.
Bohn nodules tiny multiple cysts in newborns. They are found at the junction of the hard and soft palates and along buccal and lingual parts of the dental ridges and are derived from epithelial remnants of mucous gland tissue.
Busacca nodules inflammatory, granulomatous nodules located away from the pupillary margin of the iris.
Caplan nodules SYN: Caplan syndrome.
cold n. a thyroid n. with a much lower uptake of radioactive iodine than the surrounding parenchyma; about one in four prove to be malignant.
Dalen-Fuchs nodules collections of epithelial cells lying between Bruch membrane and the retinal pigment epithelium in sympathetic ophthalmia and rarely in other granulomatous intraocular inflammations.
enamel n. SYN: enameloma.
Gamna-Gandy nodules SYN: Gamna-Gandy bodies, under body.
gastric lymphoid nodules lymphoid tissue within the lamina propria which, especially in early life, collect in small masses similar to intestinal solitary lymphatic follicles. SYN: folliculi lymphatici gastrici.
Hoboken nodules gross dilations on the outer surface of the umbilical arteries. SEE ALSO: Hoboken valves, under valve. SYN: Hoboken gemmules.
hot n. a thyroid n. with a much higher uptake of radioactive iodine than the surrounding parenchyma; usually benign but sometimes causing hyperthyroidism.
Jeanselme nodules a form of tertiary yaws that is characterized by the occurrence of nodules on the arms and legs, situated usually near the joints. SYN: juxta-articular nodules.
juxta-articular nodules SYN: Jeanselme nodules.
laryngeal lymphoid nodules small follicles located on the posterior aspect of the epiglottis and in the ventricle of the larynx. SYN: folliculi lymphatici laryngei, laryngeal tonsils, lymphatic follicles of larynx.
Lisch n. iris hamartomas typically seen in type 1 neurofibromatosis. SYN: Sakurai-Lisch n..
lymph n. SYN: lymphoid n..
lymphatic n. SYN: lymphoid n..
lymphoid n. one of the spherical masses of lymphoid cells, frequently having a more lightly staining center. See solitary lymphatic nodules, aggregated lymphoid nodules of small intestine. SYN: folliculus lymphaticus, lymph n., lymphatic n., nodulus lymphaticus.
malpighian nodules SYN: splenic lymph follicles, under follicle.
milkers' nodules an infection of cows' udders by pseudocowpox virus, a member of the Poxviridae, that is transmitted to the fingers and hands of milkers, producing nodules and lymphangitis, and occasionally widespread papular or papulovesicular eruptions; human infection is transferable to uninfected cows. SYN: milkers' nodes, paravaccinia, pseudocowpox.
Morgagni n. SYN: nodules of semilunar cusps.
picker's nodules lichenified skin nodules seen in prurigo nodularis.
primary n. a lymphatic n. having small lymphocytes and lacking a germinal center.
pseudorheumatoid nodules benign subcutaneous nodules of unknown etiology resembling rheumatoid nodules but not associated with rheumatic disease; may occur in multiple sites, such as the dorsa of the feet or hands, elbows, scalp, and pretibial area. Serologic tests for collagen vascular disease are negative. SYN: benign rheumatoid nodules.
pulp n. SYN: endolith.
rheumatoid nodules subcutaneous nodules, occurring most commonly over bony prominences, in some patients with rheumatoid arthritis; microscopically, the nodules are foci of fibrinoid necrosis, surrounded by a palisade of fibroblasts.
Sakurai-Lisch n. SYN: Lisch n..
Schmorl n. prolapse of the nucleus pulposus through the vertebral body endplate into the spongiosa of an adjacent vertebra.
secondary n. a lymphatic n. having a germinal center.
nodules of semilunar cusps [TA] a n. at the center of the free border of each semilunar valve at the beginning of the pulmonary artery and aorta. SYN: noduli valvularum semilunarium [TA] , Arantius n., Bianchi n., corpus arantii, Morgagni n., n. of semilunar valve.
n. of semilunar valve SYN: nodules of semilunar cusps.
siderotic nodules SYN: Gamna-Gandy bodies, under body.
singer's nodules SYN: vocal cord nodules.
solitary nodules of intestine SYN: solitary lymphatic nodules.
solitary lymphatic nodules [TA] minute collections of lymphoid tissue in the mucosa of the small and large intestines, being especially numerous in the cecum and appendix. SYN: noduli lymphoidei solitarii [TA] , folliculi lymphatici solitarii, solitary follicles, solitary glands, solitary lymphatic follicles, solitary nodules of intestine.
splenic lymph nodules SYN: splenic lymph follicles, under follicle.
vocal cord nodules small, circumscribed, bilateral, beadlike enlargements on the free edge of the vocal cords at the junction of the anterior one-third and the posterior two-thirds caused by overuse or abuse of the voice; often reversible by voice therapy. SYN: singer's nodes, singer's nodules, teacher's nodes.

nodulus
nodulus, pl .noduli (nod′u-lus, nod′u-li) [TA]

1. SYN: nodule. 2. The posterior extremity of the inferior vermis of the cerebellum, forming with the posterior medullary velum the central portion of the flocculonodular lobe. [L. dim. of nodus]
n. caroticus SYN: carotid body.
n. lymphaticus SYN: lymphoid nodule.
noduli lymphoidei aggregati appendicis vermiformis [TA] SYN: aggregated lymphoid nodules, under nodule.
noduli lymphoidei solitarii [TA] SYN: solitary lymphatic nodules, under nodule.
noduli valvularum semilunarium [TA] SYN: nodules of semilunar cusps, under nodule.

nodus
nodus, pl .nodi (no′dus, -di) [TA]

SYN: node. [L. a knot]
n. atrioventricularis [TA] SYN: atrioventricular node.
n. buccinatorius SYN: buccal lymph node.
n. sinuatrialis [TA] SYN: sinuatrial node.
n. tibialis anterior [TA] SYN: anterior tibial lymph node.

nodus lymphaticus
nodus lymphaticus, pl .nodi lymphatici (no′dus lim′fat′e-kus, -no′di)

lymph node. [lympho- + L. nodus, node]
nodi lymphatici colici SYN: colic lymph nodes, under lymph node.
nodi lymphatici comitantes nervi accessorii SYN: accessory lymph nodes, under lymph node.
nodi lymphatici iliaci communes mediales medial common iliac lymph nodes. See common iliac lymph nodes, under lymph node.
nodi lymphatici iliaci externi laterales external iliac lymph nodes, under lymph node.
nodi lymphatici iliaci externi mediales external iliac lymph nodes, under lymph node.
nodi lymphatici pancreatici superiores superior pancreatic lymph nodes. See pancreatic lymph nodes, under lymph node.
nodi lymphatici paravesiculares See paravesical lymph nodes, under lymph node.
nodi lymphatici postcavales right lumbar lymph nodes, under lymph node.
nodi lymphatici postvesiculares See paravesical lymph nodes, under lymph node.
nodi lymphatici prevesiculares See paravesical lymph nodes, under lymph node.
nodi lymphatici vesicales laterales See paravesical lymph nodes, under lymph node.

nodus lymphoideus
nodus lymphoideus, pl .nodi lymphoidei [TA]

SYN: lymph node.
nodi lymphoidei abdominis [TA] SYN: abdominal lymph nodes, under lymph node.
nodi lymphoidei accessorii [TA] SYN: accessory lymph nodes, under lymph node.
nodi lymphoidei anorectales SYN: pararectal lymph nodes, under lymph node.
nodi lymphoidei appendiculares [TA] SYN: appendicular lymph nodes, under lymph node.
n. arcus venae azygos SYN: lymph node of arch of azygos vein.
nodi lymphoidei axillares [TA] SYN: axillary lymph nodes, under lymph node.
nodi lymphoidei axillares anteriores SYN: pectoral axillary lymph nodes, under lymph node.
nodi lymphoidei axillares apicales [TA] SYN: apical axillary lymph nodes, under lymph node.
nodi lymphoidei axillares centrales [TA] SYN: central axillary lymph nodes, under lymph node.
nodi lymphoidei axillares humerales [TA] SYN: humeral axillary lymph nodes, under lymph node.
nodi lymphoidei axillares laterales humeral axillary lymph nodes, under lymph node.
nodi lymphoidei axillares posteriores subscapular axillary lymph nodes, under lymph node.
nodi lymphoidei axillares subscapulares [TA] SYN: subscapular axillary lymph nodes, under lymph node.
nodi lymphoidei axillares pectorales [TA] SYN: pectoral axillary lymph nodes, under lymph node.
nodi lymphoidei brachiales SYN: humeral axillary lymph nodes, under lymph node.
nodi lymphoidei brachiocephalici [TA] SYN: brachiocephalic lymph nodes.
nodi lymphoidei bronchopulmonales [TA] SYN: bronchopulmonary lymph nodes, under lymph node.
n. buccinatorius [TA] SYN: buccal lymph node.
nodi lymphoidei capitis et colli [TA] SYN: lymph nodes of head and neck, under lymph node.
nodi lymphoidei centrales SYN: superior mesenteric lymph nodes, under lymph node.
nodi lymphoidei cervicales anteriores [TA] SYN: anterior cervical lymph nodes, under lymph node.
nodi lymphoidei cervicales anteriores profundi SYN: deep anterior cervical lymph nodes, under lymph node.
nodi lymphoidei cervicales anteriores superficiales [TA] SYN: anterior superficial cervical lymph nodes, under lymph node.
nodi lymphoidei cervicales laterales profundi [TA] SYN: deep lateral cervical lymph nodes, under lymph node.
nodi lymphoidei cervicales laterales superficiales [TA] SYN: superficial lateral cervical lymph nodes, under lymph node.
nodi lymphoidei coeliaci [TA] SYN: celiac lymph nodes, under lymph node.
nodi lymphoidei colici dextri [TA] SYN: right colic lymph nodes, under lymph node.
nodi lymphoidei colici medii [TA] SYN: middle colic lymph nodes, under lymph node.
nodi lymphoidei colici sinistri [TA] SYN: left colic lymph nodes, under lymph node.
nodi lymphoidei cubitales [TA] SYN: cubital lymph nodes, under lymph node.
n. cysticus [TA] SYN: cystic lymph node.
nodi lymphoidei epigastrici inferiores [TA] SYN: inferior epigastric lymph nodes, under lymph node.
nodi lymphoidei faciales [TA] SYN: facial lymph nodes, under lymph node.
n. fibularis [TA] SYN: fibular lymph node.
n. foraminalis [TA] SYN: lymph node of anterior border of omental foramen.
nodi lymphoidei gastrici dextri [TA] SYN: right gastric lymph nodes, under lymph node.
nodi lymphoidei gastrici sinistri [TA] SYN: left gastric lymph nodes, under lymph node.
nodi lymphoidei gastroomentales dextri [TA] SYN: right gastroomental lymph nodes, under lymph node.
nodi lymphoidei gastroomentales sinistri [TA] SYN: left gastroomental lymph nodes, under lymph node.
nodi lymphoidei gluteales [TA] SYN: gluteal lymph nodes, under lymph node.
nodi lymphoidei hepatici [TA] SYN: hepatic lymph nodes, under lymph node.
nodi lymphoidei ileocolici [TA] SYN: ileocolic lymph nodes, under lymph node.
nodi lymphoidei iliaci communes [TA] SYN: common iliac lymph nodes, under lymph node.
nodi lymphoidei iliaci communes promontorii [TA] SYN: promontorial common iliac nodes, under node.
nodi lymphoidei iliaci externi [TA] SYN: external iliac lymph nodes, under lymph node.
nodi lymphoidei iliaci interni [TA] SYN: internal iliac lymph nodes, under lymph node.
nodi lymphoidei inguinales profundi SYN: deep inguinal lymph nodes, under lymph node.
nodi lymphoidei inguinales superficiales [TA] SYN: superficial inguinal lymph nodes, under lymph node.
nodi lymphoidei intercostales [TA] SYN: intercostal lymph nodes, under lymph node.
nodi lymphoidei interiliaci [TA] SYN: interiliac lymph nodes, under lymph node.
nodi lymphoidei interpectorales [TA] SYN: interpectoral lymph nodes, under lymph node.
nodi lymphoidei intrapulmonales [TA] SYN: intrapulmonary lymph nodes, under lymph node.
nodi lymphoidei jugulares anteriores SYN: anterior superficial cervical lymph nodes, under lymph node.
nodi lymphoidei jugulares laterales SYN: lateral jugular lymph nodes, under lymph node.
n. jugulodigastricus [TA] SYN: jugulodigastric lymph node.
n. juguloomohyoideus [TA] SYN: juguloomohyoid lymph node.
nodi lymphoidei juxtaesophageales [TA] SYN: juxtaesophageal lymph nodes, under lymph node.
nodi lymphoidei juxtaesophageales pulmonales SYN: juxtaesophageal lymph nodes, under lymph node.
nodi lymphoidei juxtaintestinales [TA] SYN: juxta-intestinal mesenteric lymph nodes, under lymph node.
n. lacunaris intermedius [TA] SYN: intermediate lacunar lymph node.
n. lacunaris lateralis [TA] SYN: lateral lacunar lymph node.
n. lacunaris medialis [TA] SYN: medial lacunar lymph node.
nodi lymphoidei lienales splenic lymph nodes, under lymph node.
n. ligamenti arteriosi [TA] SYN: lymph node of ligamentum arteriosum.
nodi lymphoidei linguales [TA] SYN: lingual lymph nodes, under lymph node.
nodi lymphoidei lumbales dextri [TA] SYN: right lumbar lymph nodes, under lymph node.
nodi lymphoidei lumbales intermedii [TA] SYN: intermediate lumbar lymph nodes, under lymph node.
nodi lymphoidei lumbales sinistri [TA] SYN: left lumbar lymph nodes, under lymph node.
nodi lymphoidei abdominis viscerales [TA] SYN: visceral lymph nodes of abdomen, under lymph node.
n. malaris [TA] SYN: malar lymph node.
n. mandibularis [TA] SYN: mandibular lymph node.
nodi lymphoidei mastoidei [TA] SYN: mastoid lymph nodes, under lymph node.
nodi lymphoidei mediastinales anteriores SYN: brachiocephalic lymph nodes.
nodi lymphoidei mediastinales posteriores SYN: prevertebral lymph nodes, under lymph node.
nodi lymphoidei membri inferioris [TA] SYN: lymph nodes of lower limb, under lymph node.
nodi lymphoidei membri superioris [TA] SYN: lymph nodes of upper limb, under lymph node.
nodi lymphoidei mesenterici [TA] SYN: mesenteric lymph nodes, under lymph node.
nodi lymphoidei mesenterici inferiores [TA] SYN: inferior mesenteric lymph nodes, under lymph node.
nodi lymphoidei mesenterici superiores [TA] SYN: superior mesenteric lymph nodes, under lymph node.
nodi lymphoidei mesocolici [TA] SYN: mesocolic lymph nodes, under lymph node.
n. nasolabialis [TA] SYN: nasolabial lymph node.
nodi lymphoidei obturatorii [TA] SYN: obturator lymph nodes, under lymph node.
nodi lymphoidei occipitales [TA] SYN: occipital lymph nodes, under lymph node.
nodi lymphoidei pancreatici [TA] SYN: pancreatic lymph nodes, under lymph node.
nodi lymphoidei pancreaticoduodenales [TA] SYN: pancreaticoduodenal lymph nodes, under lymph node.
nodi lymphoidei pancreaticolienales SYN: pancreaticosplenic lymph nodes, under lymph node.
nodi lymphoidei pancreaticosplenales [TA] SYN: pancreaticosplenic lymph nodes, under lymph node.
nodi lymphoidei paracolici SYN: mesocolic lymph nodes, under lymph node.
nodi lymphoidei paramammarii [TA] SYN: paramammary lymph nodes, under lymph node.
nodi lymphoidei pararectales [TA] SYN: pararectal lymph nodes, under lymph node.
nodi lymphoidei parasternales [TA] SYN: parasternal lymph nodes, under lymph node.
nodi lymphoidei paratracheales [TA] SYN: paratracheal lymph node.
nodi lymphoidei parauterini [TA] SYN: parauterine lymph nodes, under lymph node.
nodi lymphoidei paravaginales [TA] SYN: paravaginal lymph nodes, under lymph node.
nodi lymphoidei parietales [TA] SYN: parietal lymph nodes, under lymph node.
nodi lymphoidei parotidei intraglandulares [TA] SYN: intraglandular deep parotid lymph nodes, under lymph node.
nodi lymphoidei parotidei profundi [TA] SYN: deep parotid lymph nodes, under lymph node.
nodi lymphoidei parotidei profundi infra-auriculares SYN: infraauricular deep parotid lymph nodes, under lymph node.
nodi lymphoidei parotidei profundi preauriculares [TA] SYN: preauricular deep parotid lymph nodes, under lymph node.
nodi lymphoidei parotidei superficiales [TA] SYN: superficial parotid lymph nodes, under lymph node.
nodi lymphoidei pelvis [TA] SYN: pelvic lymph nodes, under lymph node.
nodi lymphoidei pericardiales laterales [TA] SYN: lateral pericardial lymph nodes, under lymph node.
nodi lymphoidei phrenici inferiores [TA] SYN: inferior phrenic lymph nodes, under lymph node.
nodi lymphoidei phrenici superiores [TA] SYN: superior phrenic lymph nodes, under lymph node.
nodi lymphoidei popliteales [TA] SYN: popliteal lymph nodes, under lymph node.
nodi lymphoidei precaecales [TA] SYN: prececal lymph nodes, under lymph node.
nodi lymphoidei prelaryngeales [TA] SYN: prelaryngeal lymph nodes, under lymph node.
nodi lymphoidei prepericardiaci [TA] SYN: prepericardial lymph nodes, under lymph node.
nodi lymphoidei pretracheales [TA] SYN: pretracheal lymph nodes, under lymph node.
nodi lymphoidei prevertebrales prevertebral lymph nodes, under lymph node.
nodi lymphoidei promontorii SYN: promontorial common iliac nodes, under node.
n. proximalis profundus [TA] SYN: proximal deep inguinal lymph node.
nodi lymphoidei pulmonales SYN: intrapulmonary lymph nodes, under lymph node.
nodi lymphoidei pylorici SYN: pyloric lymph nodes, under lymph node.
nodi lymphoidei rectales superiores [TA] SYN: superior rectal lymph nodes, under lymph node.
n. rectalis medius SYN: middle rectal lymph node.
nodi lymphoidei retrocecales [TA] SYN: retrocecal lymph nodes, under lymph node.
nodi lymphoidei retropharyngeales [TA] SYN: retropharyngeal lymph nodes, under lymph node.
nodi lymphoidei retropylorici [TA] SYN: retropyloric lymph nodes, under lymph node.
nodi lymphoidei sacrales [TA] SYN: sacral lymph nodes, under lymph node.
nodi lymphoidei sigmoidei [TA] SYN: sigmoid lymph nodes, under lymph node.
nodi lymphoidei splenici [TA] SYN: splenic lymph nodes, under lymph node.
nodi lymphoidei subaortici [TA] SYN: subaortic lymph nodes, under lymph node.
nodi lymphoidei submandibulares [TA] SYN: submandibular lymph nodes, under lymph node.
nodi lymphoidei submentales [TA] SYN: submental lymph nodes, under lymph node.
nodi lymphoidei subpylorici [TA] SYN: subpyloric lymph nodes, under lymph node.
nodi lymphoidei superiores centrales [TA] SYN: central superior mesenteric lymph nodes, under lymph node.
nodi lymphoidei supraclaviculares [TA] SYN: supraclavicular lymph nodes, under lymph node.
n. suprapyloricus [TA] SYN: suprapyloric lymph node.
nodi lymphoidei thoracis [TA] SYN: thoracic lymph nodes, under lymph node.
nodi lymphoidei thyroidei [TA] SYN: thyroid lymph nodes, under lymph node.
n. tibialis posterior [TA] SYN: posterior tibial lymph node.
nodi lymphoidei tracheobronchiales inferiores SYN: inferior tracheobronchial lymph nodes, under lymph node.
nodi lymphoidei tracheobronchiales superiores [TA] SYN: superior tracheobronchial lymph nodes, under lymph node.
nodi lymphoidei viscerales [TA] SYN: visceral lymph nodes, under lymph node.

NOE
NOE

Abbreviation for nuclear Overhauser effect.

noematic
noematic (no-e-mat′ik)

Rarely used term relating to the mental processes. [G. noema, perception, a thought]

noesis
noesis (no-e′sis)

Cognition, especially through direct and self-evident knowledge. [G. n., thought, intelligence]

noetic
noetic (no-et′ik)

Relating to noesis.

noeud vital
noeud vital (noo ve-tal′)

A circumscript region in the lower part of the medulla oblongata, near the apex of the calamus scriptorius, interpreted by M. Flourens (1858) as a nerve center controlling respiration. SYN: vital knot, vital node. [Fr.]

Noguchia
Noguchia (no-goo′che-a)

A genus of aerobic to facultatively anaerobic, motile, peritrichous bacteria (family Brucellaceae) containing small, slender, Gram-negative, encapsulated rods. These organisms are present in the conjunctiva of humans and other animals affected by a follicular type of disease. The type species is N. granulosis. [Hideyo Noguchi, Japanese bacteriologist, 1876–1928]
N. granulosis a bacterial species regarded by some as a cause of trachoma in humans; it produces a granular conjunctivitis in monkeys and apes; it is the type species of the genus N..

noise
noise (noyz)

1. Unwanted sound, particularly complex sound that lacks a musical quality because the various frequencies of which it is composed are not whole or partial number multiples (harmonics) of each other. 2. Unwanted additions to a signal not arising at its source; e.g., the 60-cycle frequency wave in an electrocardiogram; largely eliminated from modern (post-1980) machines (includes visual n. on imaging studies). See signal-to-n. ratio. 3. Extraneous uncontrolled variables influencing the distibution of measurements in a set of data. [M.E., fr. O.Fr., fr. L.L. nausea, seasickness]
structured n. in radiology, the signals from anatomic structures that interfere with the detection of significant pathology.
white n. a complex sound consisting of many frequencies over a wide band of frequencies; often used for masking of hearing in the nontest ear in the measurement of hearing.

noma
noma (no′ma)

A gangrenous stomatitis, usually beginning in the mucous membrane of the corner of the mouth or cheek, and then progressing fairly rapidly to involve the entire thickness of the lips or cheek (or both), with conspicuous necrosis and complete sloughing of tissue; usually observed in poorly nourished children and debilitated adults, especially in lower socioeconomic groups, and frequently preceded by another disease, e.g., kala azar, dysentery, or scarlet fever. A similar process (n. pudendi, n. vulvae) also may involve the labia majora. Several organisms are usually found in the necrotic material, but fusiform bacilli, Borrelia organisms, staphylococci, and anaerobic streptococci are most frequently observed. SYN: cancrum oris, stomatonecrosis, water canker. [G. nome, a spreading (sore)]

Nomarski
Nomarski

Georges, 20th century French optical inventor. See N. optics.

nomenclature
nomenclature (no′men-kla-choor, no-men′kla-choor)

A system of names as of anatomic structures, organisms, used in any science. [L. nomenclatura, a listing of names, fr. nomen, name, + calo, to proclaim]
binary n., binomial n. SYN: linnaean system of n..
Cleland n. a n. for representing the binding mechanisms of enzyme-catalyzed reactions; in this n., substrates are represented by the letters A, B, C, etc., while products are represented by P, Q, R, etc., enzyme by E, and modified forms of the enzyme by F, G, etc.; in addition, the number of substrates or products is represented by uni, bi, ter, etc.; thus, an aminotransferase reaction ( e.g., alanine transaminase) has a ping-pong bi bi mechanism, and glutamine synthetase has been reported to have a random ter ter mechanism. See also entries under subentries under mechanism.

Nomenklatur Kommission
Nomenklatur Kommission (N.K.)

Committee on Nomenclature of the German Anatomical Society, appointed to revise or supplement the BNA (1895).

nomifensine maleate
nomifensine maleate (no-mi-fen′sen)

An antidepressant.

Nomina Anatomica
Nomina Anatomica (NA) (nom′i-na an-a-tom′i-ka, no′mi-na an′a-to′mi-ka)

The modification of the Basle N. or BNA system of anatomic terminology adopted in 1955 by the International Congress of Anatomists in Paris, France. The International Anatomical Nomenclature Committee was responsible for continued revisions of the NA that had been reviewed and adopted by the International Congress of Anatomists meeting at five-year intervals from 1955 to 1985. NA was replaced by Terminologia Anatomica [TA] in 1998, produced by the Federative Committee on Anatomical Terminology.

nomogram
nomogram (nom′o-gram)

A form of line chart showing scales for the variables involved in a particular formula in such a way that corresponding values for each variable lie in a straight line intersecting all the scales. SYN: nomograph (2) . [G. nomos, law, + gramma, something written]
blood volume n. a n. used to predict blood volume on the basis of the individual's weight and height.
cartesian n. a n. based on rectangular coordinates, representing two variables, on which a family of isopleths is superimposed for each of the additional variables involved. [from R. Descartes, French philosopher and mathematician, 1596–1650]
d'Ocagne n. an alignment chart consisting of an arrangement of three or more graduated lines (straight or curved), each constituting a scale of values of a variable, constructed so that any straight line crossing these scales connects the simultaneously compatible values; from values for any two variables, the values of all other variables can be determined.
Radford n. a n. used to predict necessary tidal volume for artificial respiration on the basis of respiratory rate, body weight, and sex; correction factors are supplied for activity, fever, altitude, metabolic acidosis, and alterations in dead space.
Siggaard-Andersen n. a n. used to predict acid-base composition of blood by the slope and position of a buffer line constructed when P_CO₂ on a logarithmic scale is plotted against pH.

nomograph
nomograph (nom′o-graf)

1. A graph consisting of three coplanar curves, usually parallel, each graduated for a different variable so that a straight line cutting all three curves intersects the related values of each variable. 2. SYN: nomogram. [G. nomos, law, + grapho, to write]

nomothetic
nomothetic (nom-o-thet′ik)

Denoting the generalizations pertaining to the behavior of groups of individuals as groups, as opposed to idiographic. [G. nomos, law, + thesis, a placing]

nomotopic
nomotopic (no-mo-top′ik)

Relating to, or occurring at, the usual or normal place. [G. nomos, law, custom, + topos, place]

nonallele
nonallele (non-a-lel′)

Used of genes that are not competitors at the same locus; how independently they will behave depends on whether their loci are linked. At least when first formed (for instance, as a result of unequal crossing-over), two nonalleles may be identical.

nonan
nonan (no′nan)

Occurring on the ninth day. [L. nonus, ninth]

n-nonanoic acid
n-nonanoic acid (non-a-no′ik)

SYN: pelargonic acid.

nonapeptide
nonapeptide (non-a-pep′tid)

An oligopeptide containing nine amino acid residues ( E.G., oxytocin).

nonbursate
nonbursate (non-ber′sat)

Denoting a nontaxonomic division of Nematoda embracing those in which the male copulatory bursa is only a skin fold containing no fleshy ribs, as seen in hookworms and other bursate nematodes. [L. non, not, + Mediev. L. bursa, purse]

noncariogenic
noncariogenic (non-ka′re-o-jen′ik)

Not caries-producing.

noncellular
noncellular (non-sel′u-lar)

1. Lacking cellular organization, as applied to viruses, which can only replicate within a cell, whether prokaryotic or eukaryotic. SYN: subcellular. 2. SYN: acellular (1) .

nonchromogens
nonchromogens (non-kro′mo-jenz)

SYN: Runyon group III mycobacteria.

noncomedogenic
noncomedogenic (non-kom′e-do-jen′ik)

Tending not to promote the formation of comedones.

non compos mentis
non compos mentis (non kom′pos men′tis)

Not of sound mind; mentally incapable of managing one's affairs. [L. non, not, + compos, participating, competent, + mens, gen. mentis, mind]

nondisease
nondisease (non′dis-ez)

Absence of disease when a specific disease is suspected but not found.

nondisjunction
nondisjunction (non-dis-junk′shun)

Failure of one or more pairs of chromosomes to separate at the meiotic stage of karyokinesis, with the result that both chromosomes are carried to the one daughter cell and none to the other.
primary n. n. occurring in a previously normal cell.
secondary n. n. occurring in an aneuploid cell that was the result of a primary n..

nonelectrolyte
nonelectrolyte (non-e-lek′tro-lit)

A substance with molecules that do not, in solution, dissociate to ions and, therefore, do not carry an electric current.

nonestrogenic
nonestrogenic (non-es-tro-jen′ik)

1. Not causing estrus in animals. 2. Not having an action similar to that of an estrogen. Cf.:nonuterotropic. SYN: nonoestrogenic.

nonimmune
nonimmune (non-i-mun′)

Pertaining to an individual that is not immune or to a serum from such an individual.

nonimmunity
nonimmunity (non-i-mun′i-te)

SYN: aphylaxis.

noninfectious
noninfectious (non′in-fek′shus)

Not infectious; not able to spread disease.

noninvasive
noninvasive (non-in-va′siv)

Denoting a procedure that does not require insertion of an instrument or device through the skin or a body orifice for diagnosis or treatment.

nonionic
nonionic (non-i-on′ik)

A class of radiographic contrast media that do not ionize in solution, thereby decreasing effective osmolarity and toxicity. SEE ALSO: low osmolar contrast agent.

nonmaleficence
nonmaleficence (non-mal′ef-i-sens)

The ethical principle of doing no harm, based on the Hippocratic maxim, primum non nocere, first do no harm. [non- + L. maleficencia, evildoing, fr. male, badly, wrongly, + facio, to do, act]

nonmedullated
nonmedullated (non-med′u-lat-ed)

SYN: unmyelinated.

nonmyelinated
nonmyelinated (non-mi′e-li-nat′ed)

SYN: unmyelinated.

nonneoplastic
nonneoplastic (non′ne-o-plas′tik)

Not neoplastic.

non-nucleated
non-nucleated (non-noo′kle-a-ted)

Having no nucleus.

nonocclusion
nonocclusion (non-o-kloo′shun)

Failure of a tooth to contact an opposing tooth.

nonoestrogenic
nonoestrogenic

SYN: nonestrogenic.

nonose
nonose (non′os)

A sugar with nine carbon atoms. [L. nonus, ninth]

nonoxynol 9
nonoxynol 9 (non′noks-i-nol)

A group of compounds that are surface-acting agents, used in spermicidal preparations such as contraceptive foam and diaphragm jelly.

nonparametric
nonparametric (non-par′a-met′rik)

A group of statistical maneuvers that can be applied effectively to data nonnormal or non-Gaussian in distribution.

nonparous
nonparous (non-par′us)

SYN: nulliparous.

nonpenetrance
nonpenetrance (non-pen′e-trans)

The state in which a genetic trait, although present in the appropriate genotype ( i.e., homozygous, hemizygous, or heterozygous according to the state of dominance and mode of inheritance), fails to manifest itself in the phenotype because of modifying factors. Cf.:hypostasis.

nonproprietary name
nonproprietary name (non-pro-pri′e-tar-e)

A short name (often called a generic name) of a chemical, drug, or other substance that is not subject to trademark (proprietary) rights but is, in contrast to a trivial name, recognized or recommended by government agencies ( e.g., Federal Food and Drug Administration) and by quasi-official organizations ( e.g., U.S. Adopted Names Council) for general public use. Like a proprietary name, it is almost always a coined designation derived without using set criteria. Cf.:trivial name, proprietary name, semisystematic name, systematic name.

nonproteogenic
nonproteogenic (non-pro′te-o-jen′ik)

Not leading to the production of proteins.

nonreset nodus sinuatrialis
nonreset nodus sinuatrialis (non-re′set no′dus si′noo-a-tre-a′lis)

Nonreset of the sinoatrial node produced by a premature atrial depolarizaton when the sum of the duration of the premature cycle and the return cycle is fully compensatory, i.e., twice the duration of the spontaneous cycle length. Cf.:reset nodus sinuatrialis.

nonrotation
nonrotation (non-ro-ta′shun)

Failure of normal rotation.
n. of intestine a developmental anomaly resulting in the small intestine being on the right of the abdomen and the colon on the left.
n. of kidney a developmental anomaly in which the hilum of the kidney retains its original position, with the renal pelvis lying ventrally.

nonsaponifiable
nonsaponifiable (non-sa-pon-i-fi′a-bl)

Not subject to saponification; E.G., triacylglycerols are saponifiable but cholesterol is n..

nonsecretor
nonsecretor (non-se-kre′tor, -tor)

An individual whose saliva does not contain antigens of the ABO blood group. SEE ALSO: secretor.

nonsense
nonsense

As used in genetics, relating to a mutation that causes a sequence such that the growing peptide chain terminates, often after several incorrect amino acid residues are incorporated.
n. suppression mutant tRNAs that read a chain termination codon as the signal for incorporation of a specific amino acid residue.

nonunion
nonunion (non′un-yun)

Failure of normal healing of a fractured bone.

nonuterotropic
nonuterotropic (non-u-ter-o-tro′pik)

Not causing an effect on the uterus. Cf.:nonestrogenic.

nonvalent
nonvalent (non-va′lent)

Having no valency; not capable of entering into chemical composition.

nonvascular
nonvascular (non-vas′ku-lar)

SYN: avascular.

nonverbal
nonverbal (non-ver′bl)

Denoting communication without words, e.g., by signs, symbols, facial expressions, gestures, posture.

nonviable
nonviable (non-vi′a-bl)

1. Incapable of independent existence; often denoting a prematurely born fetus. 2. Denoting a microorganism or parasite incapable of metabolic or reproductive activity.

Noonan
Noonan

Jacqueline A., U.S. pediatric cardiologist, *1921. See N. syndrome.

nor- nor-

1. Chemical prefix denoting 1) elimination of one methylene group from a chain, the highest permissible locant being used; 2) contraction of a (steroid) ring by one CH₂ unit, the locant being the capital letter identifying the ring. Elimination of two methylene groups is denoted by the prefix dinor-; three groups, by trinor-, etc. 2. Chemical prefix denoting “normal,” i.e., unbranched chain of carbon atoms in aliphatic compounds, as opposed to branched with the same number of carbon atoms; e.g., norleucine vs. leucine.

noradrenaline
noradrenaline (nor-a-dren′a-lin)

SYN: norepinephrine.
n. acid tartrate SYN: norepinephrine bitartrate.
n. bitartrate SYN: norepinephrine bitartrate.

nordazepam
nordazepam (nor′daz-pam)

An active sedative/hypnotic of the benzodiazepine class; an active metabolite of diazepam, chlorazepate, and several other benzodiazepines; has a long biologic half-life (40–80 hours).

nordefrin hydrochloride
nordefrin hydrochloride (nor-def′rin)

A sympathomimetic and vasoconstrictor.

norepinephrine
norepinephrine (nor′ep-i-nef′rin)

l-(−)-α-(aminomethyl)-3,4-dihydroxybenzyl alcohol;a catecholamine hormone of which the natural form is d, although the l form has some activity; the base is considered to be the postganglionic adrenergic mediator, acting on α and β receptors; it is stored in chromaffin granules in the adrenal medulla, in much smaller amounts than epinephrine, and secreted in response to hypotension and physical stress; in contrast to epinephrine it has little effect on bronchial smooth muscle, metabolic processes, and cardiac output, but has strong vasoconstrictive effects and is used pharmacologically as a vasopressor, primarily as the bitartrate salt. SYN: levarterenol, noradrenaline.
n. bitartrate (-)-α-(aminomethyl)-3,4-dihydroxybenzyl alcohol tartrate. For actions and uses, see n.. SYN: levarterenol bitartrate, noradrenaline acid tartrate, noradrenaline bitartrate.

norethandrolone
norethandrolone (nor-eth-an′dro-lon)

An androgenic steroid similar chemically and pharmacologically to testosterone.

norethindrone
norethindrone (nor-eth′in-dron)

A potent orally effective progestational agent with some estrogenic and androgenic activity; used as a substitute for progesterone and, in combination with an estrogen, as an oral contraceptive. SYN: norethisterone.
n. acetate an orally active progestin with some estrogenic and androgenic activity, used to treat endometriosis and, with an estrogen, as an oral contraceptive.

norethisterone
norethisterone (nor-eth-is′ter-on)

SYN: norethindrone.

norethynodrel
norethynodrel (nor-e-thi′no-drel)

An orally active progestin with some estrogenic activity; used as a progestational agent and, in combination with mestranol, as an oral contraceptive.

norfloxacin
norfloxacin (nor-floks′a-sin)

An oral broad-spectrum quinoline antibacterial agent used in the treatment of urinary tract infections.

norgestrel
norgestrel (nor-jes′trel)

A progestin used in oral contraceptive products.

norleucine
norleucine (Nle) (nor-loo′sin)

α-Amino-n-caproic acid; 2-aminohexanoic acid;an α-amino acid, isomer of leucine and isoleucine, but not found in proteins; a deamination product of l-lysine, to which it is linked in collagens. SYN: glycoleucine.

norm
norm

1. The usual value. 2. The desirable value or behavior.

norma
norma, pl .normae (nor′ma, nor′me)

1. SYN: aspect. 2. SYN: profile (1) . 3. SYN: projection. [L. a carpenter's square]
n. anterior SYN: facial aspect.
n. basilaris SYN: external surface of cranial base.
n. facialis [TA] SYN: facial aspect.
n. frontalis facial aspect.
n. inferior SYN: external surface of cranial base.
n. lateralis [TA] SYN: lateral aspect.
n. occipitalis [TA] SYN: occipital aspect.
n. posterior SYN: occipital aspect.
n. sagittalis the outline of a sagittal section through the skull.
n. superior [TA] SYN: superior aspect.
n. temporalis SYN: lateral aspect.
n. ventralis SYN: external surface of cranial base.
n. verticalis superior aspect.

normal
normal (N) (nor′mal)

1. Typical; usual; according to the rule or standard. 2. In bacteriology, nonimmune; untreated; denoting an animal, or the serum or substance contained therein, that has not been experimentally or naturally immunized against a microorganism or its products. 3. Denoting a solution containing 1 eq of replaceable hydrogen or hydroxyl per liter; e.g., 1 mol/L HCl is 1 n, but 1 mol/L H₂SO₄ is 2 n. 4. In psychiatry and psychology, denoting a level of effective functioning that is satisfactory both to persons and to their social milieus. 5. Referring to a straight line (or plane) at a right angle to another line (or plane). 6. Not diseased or having been subjected to an experimental procedure. [L. normalis, according to pattern]

normalization
normalization (nor′mal-i-za′shun)

1. Making normal or according to the standard. 2. Reducing or strengthening of a solution to make it normal. 3. Adjusting one curve to another by multiplication of the points of the one by some arbitrary factor.

normalize
normalize (nor′mal-iz)

To effect normalization.

normative
normative

Pertaining to the normal or usual.

normeperidine
normeperidine (nor-mep′er-i-din)

A metabolite of meperidine in which the N-methyl group has been removed. The compound possesses convulsant properties.

normetanephrine
normetanephrine (nor-met′a-nef′rin)

A catabolite of norepinephrine found, together with metanephrine, in the urine and some tissues, resulting from the action of catechol-O-methyltransferase on norepinephrine; has no sympathomimetic actions.

normethadone
normethadone (nor-meth′a-don)

An antitussive with narcotic properties.

normo- normo-

Normal, usual. [L. normalis, according to pattern]

normobaric
normobaric (nor-mo-bar′ik)

Denoting a barometric pressure equivalent to sea level pressure. [normo- + G. baros, weight]

normoblast
normoblast (nor′mo-blast)

A nucleated red blood cell, the immediate precursor of a normal erythrocyte in humans. Its four stages of development are: 1) pronormoblast, 2) basophilic n., 3) polychromatic n., and 4) orthochromatic n. See erythroblast. [normo- + G. blastos, sprout, germ]

normoblastosis
normoblastosis

Excessive production of normoblasts by the bone marrow.

normocapnia
normocapnia (nor-mo-kap′ne-a)

A state in which the arterial carbon dioxide pressure is normal, about 40 mm Hg. SEE ALSO: eucapnia. [normo- + G. kapnos, vapor]

normocephalic
normocephalic (nor′mo-se-fal′ik)

SYN: mesocephalic. [normo- + G. kephale, head]

normochromia
normochromia (nor-mo-kro′me-a)

Normal color; referring to blood in which the amount of hemoglobin in the red blood cells is normal. [normo- + G. chroma, color]

normochromic
normochromic (nor-mo-kro′mik)

Being normal in color; referring especially to red blood cells that possess the normal quantity of hemoglobin.

normocyte
normocyte (nor′mo-sit)

A nonnucleated erythrocyte of normal size (average 7.5 μm); a normal, healthy red blood cell. SYN: normoerythrocyte. [normo- + G. kytos, cell]

normocytosis
normocytosis (nor′mo-si-to′sis)

A normal state of the blood with regard to its component formed elements.

normoerythrocyte
normoerythrocyte (nor′mo-e-rith′ro-sit)

SYN: normocyte.

normoglycemia
normoglycemia (nor′mo-gli-se′me-a)

SYN: euglycemia.

normoglycemic
normoglycemic (nor′mo-gli-se′mik)

SYN: euglycemic.

normokalemia
normokalemia, normokaliemia (nor′mo-ka-le′me-a, -ka-le-e′me-a)

A normal level of potassium in the blood.

normosthenuria
normosthenuria (nor′mo-sthe-noo′re-a)

Condition in which specific gravity of urine is normal. [normo- + G. sthenos, strength, + ouron, urine]

normotensive
normotensive (nor-mo-ten′siv)

Indicating a normal arterial blood pressure. SYN: normotonic (2) .

normothermia
normothermia (nor-mo-ther′me-a)

Environmental temperature that does not cause increased or depressed activity of body cells. [normo- + G. therme, heat]

normotonic
normotonic (nor-mo-ton′ik)

1. Relating to or characterized by normal muscular tone. SYN: eutonic. 2. SYN: normotensive.

normotopia
normotopia (nor-mo-to′pe-a)

The state of being in the normal place; used in reference to normal placement of an organ. [normo- + G. topos, place]

normotopic
normotopic (nor-mo-top′ik)

Relating to normotopia; in the right place.

normovolemia
normovolemia (nor′mo-vol-e′me-a)

A normal blood volume. [normo- + volume, + G. haima, blood]

normoxia
normoxia (nor-mok′se-a)

A state in which the partial pressure of oxygen in the inspired gas is equal to that of air at sea level, about 150 mm Hg. [normo- + oxygen]

norophthalmic acid
norophthalmic acid (nor′of-thal-mik)

A tripeptide analog of glutathione (l-cysteine replaced by l-alanine), found in the lens of the eye.

norpipanone
norpipanone (nor-pip′a-non)

An analgesic agent.

Norrie
Norrie

Gordon, Danish ophthalmologist, 1855–1941. See N. disease.

Norris
Norris

Richard, English physiologist, 1830–1916. See N. corpuscles, under corpuscle.

norsteroids
norsteroids (nor-ster′oydz)

Steroids in which an angular methyl group is missing; most commonly, the group between the A and B rings (C-19).

norsympatol
norsympatol (nor-sim′pa-tol)

SYN: octopamine.

norsynephrine
norsynephrine (nor-si-nef′rin)

SYN: octopamine.

Norton
Norton

U.F., U.S. obstetrician. See N. operation.

Norton
Norton

Larry, 20th century U.S. oncologist. See N.-Simon hypothesis.

nortriptyline hydrochloride
nortriptyline hydrochloride (nor-trip′ti-len)

An antidepressant.

norvaline
norvaline (Nva) (nor-val′en, -va′len)

α-Aminovaleric acid;the straight chain analog of valine; not found in proteins.

noscapine
noscapine (nos′ka-pen)

An isoquinoline alkaloid, occurring in opium, with papaverine-like action on smooth muscle; suppresses the cough reflex and is used as an antitussive; it appears to be without addiction liability. SYN: l-α-narcotine, opianine.

nose
nose (noz)

That portion of the respiratory pathway above the hard palate; includes both the external n. and the nasal cavity. SYN: nasus (2) . [A.S. nosu]
brandy n. SYN: rhinophyma.
cleft n. a n. with a furrow caused by failure of complete convergence of the embryonic primordia.
copper n. SYN: rhinophyma.
dog n. SYN: goundou.
external n. the visible portion of the n. that forms a prominent feature of the face; it consists of a root, dorsum, and apex from above downward and is perforated inferiorly by two nostrils separated by a septum. SYN: nasus externus, nasus (1) .
hammer n. SYN: rhinophyma.
potato n. SYN: rhinophyma.
rum n. SYN: rhinophyma.
saddle n. a n. with markedly depressed bridge, seen in congenital syphilis, after injury from trauma or operation, or infection of the nasal septum.
toper's n. SYN: rhinophyma.

nosebleed
nosebleed (nos′bled)

SYN: epistaxis.

Nosema
Nosema (no-se′ma)

A protozoan genus (family Nosematidae, order Microsporida, phylum Microspora) with species (N. apis, N. bombycis, and others) pathogenic for invertebrates of economic importance (bees, silkworms); others are being studied as possible agents of biologic control of pest insects or other target invertebrates. N. connori infects human fat tissue, diaphragm, myocardium, liver, and other tissues of immunosuppressed individuals. [G. n., plague, fr. noseo, to be sick, fr. nosos, disease]
N. corneum a cause of keratoconjunctivitis and diffuse punctate keratopathy in AIDS patients.

Nosematidae
Nosematidae (no-se-mat′i-de)

A family of the class Microsporida that includes the genera Encephalitozoon and Nosema, containing several pathogenic and economically important species.

nosematosis
nosematosis (no-se′ma-to′sis)

An infection of rabbits with the protozoan parasite Encephalitozoon cuniculi that can cause a focal interstitial nephritis; one case of n. has been reported in humans.

nosepiece
nosepiece (nos′pes)

A microscope attachment, consisting of several objectives surrounding a central pivot.

nosetiology
nosetiology (nos′e-te-ol′o-je)

Rarely used term for the study of the causes of disease. [G. nosos, disease, + aitia, cause, + logos, study]

noso- noso-

Disease. SEE ALSO: path-. [G. nosos]

nosoacusis
nosoacusis (no-so-ak-u′sis)

Hearing loss due to disease, as opposed to aging. [noso- + G. akousis, hearing]

nosochthonography
nosochthonography (nos′ok-tho-nog′ra-fe)

SYN: geomedicine. [noso- + G. chthon, the earth, + graphe, a description]

nosocomial
nosocomial (nos-o-ko′me-al)

1. Relating to a hospital. 2. Denoting a new disorder (not the patient's original condition) associated with being treated in a hospital, such as a hospital-acquired infection. [G. nosokomeion, hospital, fr. nosos, disease, + komeo, to take care of]

nosogenesis
nosogenesis, nosogeny (nos-o-jen′e-sis, no-soj′e-ne)

Rarely used terms for pathogenesis. [noso- + G. genesis, production]

nosogenic
nosogenic (nos-o-jen′ik)

SYN: pathogenic.

nosogeography
nosogeography (nos′o-je-og′ra-fe)

SYN: geomedicine.

nosographic
nosographic (nos-o-graf′ik)

Relating to nosography, or the description of diseases.

nosography
nosography (no-sog′ra-fe)

1. Assignment of names to each disease entity in a group that has been classified according to a systematic nosology. 2. A treatise on pathology or the practice of medicine. [noso- + G. graphe, description]

nosologic
nosologic (nos-o-loj′ik)

Relating to nosology.

nosology
nosology (no-sol′o-je)

The science of classification of diseases. SYN: nosonomy, nosotaxy. [noso- + G. logos, study]
psychiatric n. SYN: psychonosology.

nosomania
nosomania (nos-o-ma′ne-a)

A rarely used term for an unfounded morbid belief that one is suffering from some special disease. [noso- + G. mania, insanity]

nosometry
nosometry (no-som′e-tre)

Measurement of morbidity or of the sickness rate in occupations and social conditions. [noso- + G. metron, measure]

nosomycosis
nosomycosis (nos′o-mi-ko′sis)

Any disease caused by a fungus. [noso- + G. mykes, fungus]

nosonomy
nosonomy (no-son′o-me)

SYN: nosology. [noso- + G. nomos, law]

nosophilia
nosophilia (nos-o-fil′e-a)

A morbid desire to be sick. [noso- + G. phileo, to love]

nosophobia
nosophobia (nos-o-fo′be-a)

An inordinate dread and fear of disease. SYN: pathophobia. [noso- + G. phobos, fear]

nosophyte
nosophyte (nos′o-fit)

A pathogenic microorganism of the plant kingdom. [noso- + G. phyton, plant]

nosopoietic
nosopoietic (nos′o-poy-et′ik)

SYN: pathogenic. [noso- + G. poiesis, a making]

Nosopsyllus
Nosopsyllus (nos-o-sil′us)

A flea genus commonly found on rodents. N. fasciatus, the northern rat flea, is a species that infrequently transmits the plague bacillus to humans. [noso- + G. psylla, flea]

nosotaxy
nosotaxy (nos′o-tak-se)

SYN: nosology. [noso- + G. taxis, arrangement]

nosotoxic
nosotoxic (nos-o-tok′sik)

Relating to a nosotoxin or to nosotoxicosis.

nosotoxicosis
nosotoxicosis (nos′o-tok-si-ko′sis)

A morbid state caused by a toxin. SEE ALSO: toxicosis. [noso- + G. toxikon, poison]

nosotoxin
nosotoxin (nos-o-tok′sin)

Rarely used term for any toxin associated with a disease.

nosotrophy
nosotrophy (nos-ot′ro-fe)

Rarely used term for care of the sick. [noso- + G. trophe, nourishment]

nosotropic
nosotropic (nos-o-trop′ik)

Directed against the pathologic changes or symptoms of a disease. [noso- + G. trope, a turning]

nostalgia
nostalgia (nos-tal′je-a)

The longing to return home, to a former time in one's life, or to familiar people and surroundings. [G. nostos, a return (home), + algos, pain]

nostomania
nostomania (nos-to-ma′ne-a)

A rarely used term for an obsessive or abnormal interest in nostalgia, especially as an extreme manifestation of homesickness. [G. nostos, return, homecoming, + mania, frenzy]

nostophobia
nostophobia (nos-to-fo′be-a)

Morbid fear of returning home. [G. nostos, return, homecoming, + phobos, fear]

nostril
nostril

SYN: naris.
internal n. SYN: secondary choana.

nostrum
nostrum (nos′trum)

General term for a therapeutic agent, sometimes patented but usually of secret composition, offered to the general public as a specific remedy for any disease or class of diseases. Term presently carries pejorative connotation. [L. neuter of noster, our, “our own remedy”]

NO synthase
NO synthase

Abbreviation for nitric oxide synthase.

notal
notal (no′tal)

Relating to the back. [G. notos, the back]

notancephalia
notancephalia (no′tan-se-fa′le-a)

Fetal malformation characterized by absence of the occipital bone of the cranium. [G. notos, back, + an- priv. + kephale, head]

notanencephalia
notanencephalia (no′tan-en-se-fa′le-a)

Absence of the cerebellum. [G. notos, back, + an- priv. + enkephalos, brain]

notatin
notatin (no-ta′tin)

A protein (glucose oxidase) that has specifically been isolated from Penicillium notatum. [from Penicillium notatum]

notch
notch [TA]

1. An indentation at the edge of any structure. 2. Any short, narrow, V-shaped deviation, whether positive or negative, in a linear tracing. SYN: incisura [TA] , emargination, incisure.
acetabular n. [TA] a gap in the inferior the margin of the acetabulum. SYN: incisura acetabuli [TA] , cotyloid n..
angular n. SYN: angular incisure.
antegonial n. the highest point of the n. or concavity of the lower border of the ramus where it joins the body of the mandible.
anterior n. of auricle [TA] a n. between the supratragic tubercle and the crus of the helix. SYN: anterior auricular groove, anterior n. of ear, auricular n. (1) , incisura anterior auris, sulcus auriculae anterior.
anterior cerebellar n. a wide, shallow n. on the anterior surface of the cerebellum occupied laterally by the superior cerebellar peduncles and the inferior quadrigeminal bodies medially. SYN: anterior n. of cerebellum, incisura cerebelli anterior, semilunar n. (1) .
anterior n. of cerebellum SYN: anterior cerebellar n..
anterior n. of ear SYN: anterior n. of auricle.
aortic n. the n. in a sphygmographic tracing caused by rebound following closure of the aortic valves.
n. of apex of heart SYN: n. of cardiac apex.
auricular n. 1. SYN: anterior n. of auricle. 2. SYN: terminal n. of auricle.
cardiac n. SYN: cardial n..
n. of cardiac apex [TA] a slight n. near the apex of the heart where the anterior interventricular sulcus reaches the diaphragmatic surface of the heart. SYN: incisura apicis cordis [TA] , n. of apex of heart.
cardiac n. of left lung [TA] the n. in the anterior border of the superior lobe of the left lung that accommodates the pericardium. SYN: incisura cardiaca pulmonis sinistri [TA] .
cardial n. [TA] a deep n. between the esophagus and fundus of the stomach. SYN: cardiac n., incisura cardiaca.
n. in cartilage of acoustic meatus [TA] (usually) two vertical fissures in the anterior portion of the cartilage of the external auditory meatus, filled by fibrous tissue. SYN: incisura cartilaginis meatus acustici [TA] , Duverney fissures, incisura santorini, Santorini fissures, Santorini incisures.
clavicular n. of sternum [TA] a hollow on either side of the upper surface of the manubrium sterni that articulates with the clavicle. SYN: incisura clavicularis [TA] , clavicular facet.
costal notches [TA] notches or facets on the lateral edge of the sternum for articulation with a costal cartilage. SYN: incisurae costales [TA] .
cotyloid n. SYN: acetabular n..
dicrotic n. (di-krot-ik) the acute drop followed by a rise in arterial pressure pulse curves following the systolic peak, corresponding to the incisura of the displacement pulse curve.
digastric n. SYN: mastoid n..
ethmoidal n. [TA] an oblong gap between the orbital parts of the frontal bone in which the ethmoid bone is lodged. SYN: incisura ethmoidalis [TA] .
fibular n. [TA] a hollow on the lateral surface of the lower end of the tibia in which the fibula is lodged. SYN: incisura fibularis [TA] .
frontal n. [TA] a small n., sometimes a foramen, on the orbital margin of the frontal bone medial to the supraorbital n.. SYN: incisura frontalis [TA] .
greater sciatic n. [TA] the deep indentation in the posterior border of the hip bone at the point of union of the ilium and ischium. SYN: incisura ischiadica major [TA] , iliosciatic n., sacrosciatic n..
hamular n. SYN: groove of pterygoid hamulus.
Hutchinson crescentic n. the semilunar n. on the incisal edge of Hutchinson teeth, encountered in congenital syphilis.
iliosciatic n. SYN: greater sciatic n..
inferior thyroid n. [TA] a shallow n. in the middle of the lower border of the thyroid cartilage. SYN: incisura thyroidea inferior [TA] .
interarytenoid n. [TA] the indentation of posterior portion of the aditus laryngeal inlet between the two arytenoid cartilages. SYN: incisura interarytenoidea [TA] .
interclavicular n. SYN: jugular n. of sternum.
intercondyloid n. SYN: intercondylar fossa.
intertragic n. [TA] the deep n. in the lower part of the auricle between the tragus and antitragus. SYN: incisura intertragica [TA] , incisura tragica.
intervertebral n. SYN: vertebral n..
ischiatic n. greater sciatic n., lesser sciatic n..
jugular n. of occipital bone [TA] the n. in the occipital bone that forms one boundary of the jugular foramen. SYN: incisura jugularis ossis occipitalis [TA] .
jugular n. of petrous part of temporal bone [TA] the n. in the petrous part of the temporal bone that forms one boundary of the jugular foramen. SYN: incisura jugularis ossis temporalis [TA] .
jugular n. of sternum [TA] the large n. in the superior margin of the sternum. SYN: incisura jugularis sternalis [TA] , suprasternal n.&star, interclavicular n., presternal n., sternal n..
Kernohan n. a n. in the cerebral peduncle caused by displacement of the brainstem against the incisura of the tentorium by a transtentorial herniation.
lacrimal n. [TA] the n. on the frontal process of the maxilla into which the lacrimal bone fits. SYN: incisura lacrimalis [TA] .
lesser sciatic n. [TA] the n. in the posterior border of the ischium below the ischial spine. SYN: incisura ischiadica minor [TA] .
n. for ligamentum teres [TA] the n. in the inferior border of the liver that accommodates the round ligament. SYN: incisura ligamenti teretis hepatis [TA] , incisura umbilicalis, n. for round ligament of liver, umbilical n..
mandibular n. [TA] the deep n. between the condylar and coronoid processes of the mandible. SYN: incisura mandibulae [TA] , sigmoid n..
marsupial n. SYN: posterior cerebellar n..
mastoid n. [TA] the groove medial to the mastoid process of the temporal bone from which the digastric muscle originates. SYN: incisura mastoidea [TA] , digastric groove, digastric n., mastoid groove.
nasal n. [TA] the n. in the medial border of the maxilla anteriorly that, with its fellow, forms most of the piriform opening of the nasal cavity. SYN: incisura nasalis [TA] .
pancreatic n. [TA] a n. separating the uncinate process of the head of the pancreas from the neck. SYN: incisura pancreatis [TA] .
parietal n. [TA] the angle posteriorly between the squamous and petrous parts of the temporal bone. SYN: incisura parietalis [TA] .
parotid n. the space between the ramus of the mandible and the mastoid process of the temporal bone.
popliteal n. SYN: intercondylar fossa.
posterior cerebellar n. a narrow n. between the cerebellar hemispheres posteriorly, occupied by the falx cerebelli. SYN: incisura cerebelli posterior, marsupial n., posterior n. of cerebellum.
posterior n. of cerebellum SYN: posterior cerebellar n..
preoccipital n. [TA] an indentation in the ventrolateral border of the temporal lobe of the cerebral hemisphere. SYN: incisura preoccipitalis [TA] .
presternal n. SYN: jugular n. of sternum.
pterygoid n. [TA] the cleft between the medial and lateral plates of the pterygoid process of the sphenoid into which the pyramidal process of the palatine bone is fitted. SYN: fissura pterygoidea, incisura pterygoidea, pterygoid fissure.
pterygomaxillary n. SYN: groove of pterygoid hamulus.
radial n. [TA] the concavity on the lateral aspect of the coronoid process of the ulna that articulates with the head of the radius. SYN: incisura radialis [TA] .
Rivinus n. SYN: tympanic n..
n. for round ligament of liver SYN: n. for ligamentum teres.
sacrosciatic n. SYN: greater sciatic n..
scapular n. SYN: suprascapular n..
semilunar n. 1. SYN: anterior cerebellar n.. 2. SYN: trochlear n..
sigmoid n. SYN: mandibular n..
sphenopalatine n. [TA] the deep n. between the orbital and sphenoidal processes of the palatine bone that is converted into the foramen of the same name by the undersurface of the sphenoid bone. SYN: incisura sphenopalatina [TA] .
sternal n. SYN: jugular n. of sternum.
superior thyroid n. [TA] a deep n. in the middle of the upper border of the thyroid cartilage. SYN: incisura thyroidea superior [TA] .
supraorbital n. [TA] a groove in the orbital margin of the frontal bone, about the junction of the medial and intermediate thirds, through which pass the supraorbital nerve and artery. SEE ALSO: supraorbital foramen. SYN: incisura supraorbitalis [TA] .
suprascapular n. a n. on the superior border of the scapula through which the suprascapular nerve passes. SYN: incisura scapulae, scapular n..
suprasternal n. jugular n. of sternum.
tentorial n. [TA] the triangular opening in the tentorium cerebelli through which the brainstem extends from the posterior into the middle cranial fossa. SYN: incisura tentorii [TA] , incisura of tentorium&star, n. of tentorium.
n. of tentorium SYN: tentorial n..
terminal n. of auricle [TA] a deep n. separating the lamina tragi and cartilage of the external auditory meatus from the main auricular cartilage, the two being connected below by the isthmus. SYN: incisura terminalis auricularis [TA] , auricular n. (2) , incisura terminalis auris.
trochlear n. [TA] the large semicircular n. at the proximal extremity of the ulna between the olecranon and coronoid processes that articulates with the trochlea of the humerus. SYN: incisura trochlearis [TA] , incisura semilunaris ulnae, semilunar n. (2) .
tympanic n. [TA] the n. in the superior part of the tympanic ring bridged by the flaccid part of the tympanic membrane. SYN: incisura tympanica [TA] , incisura rivini, Rivinus incisure, Rivinus n., tympanic incisure.
ulnar n. [TA] the concave surface on the medial side of the distal end of the radius that articulates with the head of the ulna. SYN: incisura ulnaris [TA] .
umbilical n. SYN: n. for ligamentum teres.
vertebral n. [TA] one of the two concavities above (superior) and below (inferior) the pedicle of a vertebra; the notches of two adjacent vertebrae (plus the intervertebral disc) form an intervertebral foramen. SYN: incisura vertebralis [TA] , intervertebral n..

notched
notched

SYN: emarginate.

notencephalocele
notencephalocele (no-ten-sef′a-lo-sel)

Malformation in the occipital portion of the cranium with protrusion of brain substance. [G. notos, back, + enkephalos, brain, + kele, hernia]

Nothnagel
Nothnagel

C.W. Hermann, Austrian physician, 1841–1905. See N. syndrome.

notochord
notochord (no′to-kord)

1. In primitive vertebrates, the primary axial supporting structure of the body, derived from the notochordal or head process of the early embryo; an important organizer for determining the final form of the nervous system and related structures. 2. In embryos, the axial fibrocellular cord about which the vertebral primordia develop; vestiges of it persist in the adult as the nuclei pulposi of the intervertebral discs. SYN: chorda dorsalis. [G. notos, back, + chorde, cord, string]

notochordal
notochordal (no-to-kor′dal)

Relating to the notochord.

Notoedres cati
Notoedres cati (no-to-ed′rez ka′ti)

Sarcoptic mange mite of cats.

noumenal
noumenal (noo′men-al)

Intellectually, not sensuously or emotionally, intuitional; relating to the object of pure thought divorced from all concepts of time or space. [G. nooumenos, perceived, fr. noeo, to perceive, think]

nourishment
nourishment (ner′ish-ment)

A substance used to feed or to sustain life and growth of an organism. SYN: aliment (1) .

nous
nous (noos, nows)

A word originally used by Anaxagoras to mean an all-knowing, all-pervading spirit or force; in later Greek philosophy it came to mean simply mind, reason, or intellect. [G. mind, reason]

novobiocin
novobiocin (no-vo-bi′o-sin)

An antibiotic antibacterial substance produced by fermentation from cultures of Streptomyces niveus or S. spheroides, effective against penicillin-resistant Staphylococcus and Proteus; also available as n. calcium and n. sodium. SYN: streptonivicin.

Novy
Novy

Frederick George, U.S. bacteriologist, 1864–1957. See N. and MacNeal blood agar.

noxa
noxa (nok′sa)

Anything that exerts a harmful influence, such as trauma, poison, etc. [L. injury, fr. noceo, to injure]

noxious
noxious (nok′shus)

Injurious; harmful. [L. noxius, injurious, fr. noceo, to injure]

noxythiolin
noxythiolin (nok-se-thi′o-lin)

An antibacterial and antifungal agent.

Np
Np

1. Symbol for neptunium. 2. Abbreviation for neper.

NPC
NPC

Abbreviation for Niemann-Pick C1 disease.

NPN
NPN

Abbreviation for nonprotein nitrogen.

NPO
NPO, n.p.o.

Abbreviation for L. non per os or nil per os, nothing by mouth.

Nps
Nps

Abbreviation for nitrophenylsulfenyl.

NREM
NREM

Abbreviation for nonrapid eye movement.

nRNA
nRNA

Abbreviation for nuclear RNA.

NSAID
NSAID

Abbreviation for nonsteroidal anti-inflammatory drugs, under drug; e.g., aspirin, ibuprofen.

NSF
NSF

Abbreviation for National Science Foundation.

NSILA
NSILA

Abbreviation for nonsuppressible insulinlike activity.

NTMI
NTMI

Abbreviation for nontransmural myocardial infarction.

NTNG
NTNG

Abbreviation for nontoxic nodular goiter.

NTP
NTP

Abbreviation for nucleoside 5′-triphosphate.

nu
nu (noo)

Thirteenth letter of the Greek alphabet, &n.; (q.v.).

nubecula
nubecula (noo-bek′u-la)

A faint cloud or cloudiness. [L. dim. of nubes, cloud]

Nuc
Nuc

Abbreviation for nucleoside.

nucha
nucha (noo′ka)

The back of the neck. SYN: nape. [Fr. nuque]

nuchal
nuchal (noo′kal)

Relating to the nucha.

Nuck
Nuck

Anton, Dutch anatomist, 1650–1692. See N. diverticulum, N. hydrocele, canal of N..

nucl- nucl-

See nucleo-.

nuclear
nuclear (noo′kle-er)

Relating to a nucleus, either cellular or atomic; in the latter sense, usually referring to radiation emanating from atomic nuclei (α, β, or γ) or to atomic fission.

Nuclear Regulatory Commission
Nuclear Regulatory Commission

The U.S. federal commission supervising the use of radioactive by-product material for commercial and medical purposes; successor to the Atomic Energy Commission along with the U.S. Department of Energy.

nuclease
nuclease (noo′kle-as)

General term for enzymes that catalyze the hydrolysis of nucleic acid into nucleotides or oligonucleotides by cleaving phosphodiester linkages. For nucleases not listed below, see the specific term. Cf.:exonuclease, endonuclease.
azotobacter n. endonuclease (Serratia marcescens).
micrococcal n. SYN: micrococcal endonuclease.
mung bean n. endonuclease S₁ (Aspergillus).

nucleate
nucleate (noo′kle-at)

A salt of a nucleic acid.

nucleated
nucleated (noo′kle-a-ted)

Provided with a nucleus, a characteristic of all true cells.

nucleation
nucleation (noo-kle-a′shun)

Process of forming a nidus (4).
heterogeneous n. n. about a nidus composed of material other than that precipitating.
homogeneous n. n. about a nidus composed of material identical with that precipitating.

nuclei
nuclei (noo′kle-i)

Plural of nucleus.

nucleic acid
nucleic acid (noo-kle′ik, -kla′ik)

A family of macromolecules, of molecular masses ranging upward from 25,000, found in the chromosomes, nucleoli, mitochondria, and cytoplasm of all cells, and in viruses; in complexes with proteins, they are called nucleoproteins. On hydrolysis they yield purines, pyrimidines, phosphoric acid, and a pentose, either d-ribose or d-deoxyribose; from the last, the nucleic acids derive their more specific names, ribonucleic acid and deoxyribonucleic acid. Nucleic acids are linear ( i.e., unbranched) chains of nucleotides in which the 5′-phosphoric group of each one is esterified with the 3′-hydroxyl of the adjoining nucleotide.
infectious n. viral n. that can infect cells and bring about the production of viruses.

nucleiform
nucleiform (noo′kle-i-form)

Shaped like or having the appearance of a nucleus. SYN: nucleoid (1) .

nucleo- nucleo-, nucl-

Nucleus, nuclear. SEE ALSO: karyo-, caryo-. [L. nucleus]

nucleocapsid
nucleocapsid (noo′kle-o-kap′sid)

See virion.

nucleochylema
nucleochylema (noo-kle-o-ki-le′ma)

SYN: karyolymph. [nucleo- + G. chylos, juice]

nucleochyme
nucleochyme (noo′kle-o-kim)

SYN: karyolymph.

nucleofilaments
nucleofilaments (noo′kle-o-fil′-a-ments)

A filamentary form of chromosome formed in low ionic strength solutions; fibers are about 100 Å wide and have a string-of-beads appearance.

nucleohistone
nucleohistone (noo′kle-o-his′ton)

A complex of histone and deoxyribonucleic acid, the form in which the latter is usually found in the nuclei of cells; n. may be viewed as a salt between the basic protein and the acidic nucleic acid.

nucleoid
nucleoid (noo′kle-oyd)

1. SYN: nucleiform. 2. A nuclear inclusion body. 3. SYN: nucleus (2) . [nucleo- + G. eidos, resemblance]
Lavdovsky n. SYN: astrosphere.

nucleolar
nucleolar (noo-kle′o-lar)

Relating to a nucleolus.

nucleoli
nucleoli (noo-kle′o-li)

Plural of nucleolus.

nucleoliform
nucleoliform (noo-kle′o-le-form)

Resembling a nucleolus. SYN: nucleoloid.

nucleoloid
nucleoloid (noo-kle′o-loyd)

SYN: nucleoliform. [nucleolus + G. eidos, resemblance]

nucleolonema
nucleolonema (noo-kle′o-lo-ne′ma)

The irregular network or rows of fine ribonucleoprotein granules or microfilaments forming most of the nucleolus. [nucleolus + G. nema, thread]

nucleolus
nucleolus, pl .nucleoli (noo-kle′o-lus, -li)

1. A small rounded mass within the cell nucleus where ribonucleoprotein is produced; it is usually single, but there may be several accessory nucleoli besides the principal one. The n. is composed of a meshwork (nucleolonema) of microfilaments and granules and the pars amorpha, now shown to have microfilaments also. 2. A more or less central body in the vesicular nucleus of certain protozoa in which an endosome is lacking but one or more Feulgen-positive (DNA+) nucleoli are present; characteristic of certain sporozoans, flagellates, opalinids, dinoflagellates, and radiolarians among the Protozoa. The chromatin material is distributed throughout the nucleus rather than peripherally, as in the endosome type of nucleus of Entamoeba. [L. dim of nucleus, a nut, kernel]
chromatin n. SYN: karyosome.
false n. SYN: karyosome.

nucleomicrosome
nucleomicrosome (noo′kle-o-mi′kro-som)

SYN: karyomicrosome.

nucleon
nucleon (noo′kle-on)

1. One of the subatomic particles of the atomic nucleus; i.e., either a proton or a neutron. 2. Slang term for specialist in nuclear medicine. [nucleus + -on]

Nucleophaga
Nucleophaga (noo-kle-of′a-ga)

A microsporan parasite of amebae that destroys the nucleus of its host. [nucleo- + G. phago, to eat]

nucleophil
nucleophil, nucleophile (noo′kle-o-fil, -fil)

1. The electron pair donor atom in a chemical reaction in which a pair of electrons is picked up by an electrophil; any reagent or substance that is attracted to a region of low electron density. 2. Relating to a n.. SYN: nucleophilic (1) . [nucleo- + G. philos, fond]

nucleophilic
nucleophilic (noo′kle-o-fil′ik)

1. SYN: nucleophil (2) . 2. A reaction involving a nucleophile.

nucleophosphatases
nucleophosphatases (noo′kle-o-fos′fa-tas-ez)

SYN: nucleotidases.

nucleoplasm
nucleoplasm (noo′kle-o-plazm)

The protoplasm of the nucleus of a cell.

nucleoplasmin
nucleoplasmin (noo′kle-plas′min)

Contents of resting (interphase) nucleus. [nucleo- + plasma + -in]

nucleoprotein
nucleoprotein (noo′kle-o-pro′ten)

A complex of protein and nucleic acid, the form in which essentially all nucleic acids exist in nature; chromosomes and viruses are largely n..

nucleoreticulum
nucleoreticulum (noo′kle-o-re-tik′u-lum)

The intranuclear network of chromatin or linin. [nucleo- + L. reticulum, dim. of rete, net]

nucleorrhexis
nucleorrhexis (noo′kle-o-rek′sis)

Fragmentation of a cell nucleus. [nucleo- + G. rhexis, rupture]

nucleosidases
nucleosidases (noo′kle-o-si′das-ez)

Enzymes (particularly EC subgroup 3.2.2) that catalyze the hydrolysis or phosphorolysis of nucleosides, releasing the purine or pyrimidine base.

nucleoside
nucleoside (Nuc, N) (noo′kle-o-sid)

A compound of a sugar (usually ribose or deoxyribose) with a purine or pyrimidine base by way of an N-glycosyl link.
n. bisphosphate a n. that carries two independent ( i.e., not linked to each other) phosphoric residues. Cf.:n. diphosphate.
n. diphosphate (NDP) the pyrophosphoric ester of a n., i.e., a n. in which the H of one of the ribose hydroxyls (usually the 5′) is replaced by a pyrophosphoric (diphosphoric) radical; e.g., adenosine 5′-diphosphate. Cf.:n. bisphosphate.
n. monophosphate a nucleotide containing only one phosphoryl group, e.g., AMP.
n. triphosphate a n. in which the H of one of the ribose hydroxyls (usually the 5′) is replaced by a triphosphoric group, –PO(OH)–O–PO(OH)–O–PO(OH)₂ or the corresponding conjugate base; e.g., adenosine triphosphate.

nucleoside diphosphate kinase
nucleoside diphosphate kinase

A phosphotransferase reversibly catalyzing the transfer of one phosphoryl group from ATP to a nucleoside diphosphate to yield a nucleoside triphosphate and ADP.

nucleoside diphosphate sugars
nucleoside diphosphate sugars

Nucleoside diphosphates linked through the 5′-diphosphoric group with simple or complex carbohydrates; e.g., GDPmannose, UDPglucose (UDPG), dTDPglucosamine.

nucleoskeleton
nucleoskeleton (nook′le-o-skel′e-ton)

Proteins forming a fibrillar substructure of the nuclear matrix to which DNA is bound.

nucleosome
nucleosome (noo′kle-o-som)

A localized aggregation of histone and DNA that is evident when chromatin is in the uncondensed stage. SYN: nu body. [nucleo- + G. soma, body]

nucleospindle
nucleospindle (noo′kle-o-spin′dl)

The fusiform body in mitosis.

nucleotidases
nucleotidases (noo′kle-o-ti-das-ez)

Enzymes (EC 3.1.3.x) that catalyze the hydrolysis of nucleotides into phosphoric acid and nucleosides; specificities are indicated by prefixes 3′- and 5′-. SYN: nucleophosphatases.

nucleotide
nucleotide (noo′kle-o-tid)

Originally a combination of a (nucleic acid) purine or pyrimidine, one sugar (usually ribose or deoxyribose), and a phosphoric group; by extension, any compound containing a heterocyclic compound bound to a phosphorylated sugar by an N-glycosyl link ( e.g., adenosine monophosphate, NAD⁺). For individual nucleotides see specific names. SYN: mononucleotide.
cyclic n. a nucleoside monophosphate in which the phosphoryl group is linked twice to the sugar moiety; e.g., adenosine 3′,5′-cyclic monophosphate (cAMP).
flavin n. flavin.

nucleotidyltransferases
nucleotidyltransferases (noo′kle-o-ti′dil-trans′fer-as-ez)

Enzymes (EC 2.7.7.x) transferring nucleotide residues (nucleotidyls) from nucleoside di- or triphosphates into dimer or polymer forms. Some n. bear specific names ( e.g., adenylyltransferases), trivial names indicating the linkage hydrolyzed in the synthesis (pyrophosphorylases, phosphorylases), or names of the material synthesized (RNA or DNA polymerase).

nucleotoxin
nucleotoxin (noo′kle-o-tok′sin)

A toxin acting upon the cell nuclei.

nucleus
nucleus, pl .nuclei (noo′kle-us, noo′kle-i)

1. In cytology, typically a rounded or oval mass of protoplasm within the cytoplasm of a plant or animal cell; it is surrounded by a nuclear envelope, which encloses euchromatin, heterochromatin, and one or more nucleoli and undergoes mitosis during cell division. SYN: karyon. 2. By extension, because of similar function, the genome of microorganisms (microbes), which is relatively simple in structure, lacks a nuclear membrane and does not undergo mitosis during replication. SYN: nucleoid (3) . SEE ALSO: virion. 3. [TA] In neuroanatomy, a group of nerve cell bodies in the brain or spinal cord that can be demarcated from neighboring groups on the basis of either differences in cell type or the presence of a surrounding zone of nerve fibers or cell-poor neuropil. 4. Any substance ( e.g., foreign body, mucus, crystal) around which a urinary or other calculus is formed. 5. The central portion of an atom (composed of protons and neutrons) where most of the mass and all of the positive charge are concentrated. 6. A particle on which a crystal, droplet, or bubble forms. 7. A characteristic arrangement of atoms in a series of molecules; e.g., the benzene n. is a series of aromatic compounds. [L. a little nut, the kernel, stone of fruits, the inside of a thing, dim. of nux, nut]
abducens n., n. abducentis, n. of abducens nerve a group of motor neurons in the lower part of the pons, innervating the ipsilateral lateral rectus muscle of the eye; unique among motor cranial nerve nuclei in that it consists of two distinct populations of neurons: neurons that give rise to fibers forming the abducens nerve root and those internuclear neurons whose processes cross the midline, ascend in the opposite medial longitudinal fasciculus, and terminate upon specific oculomotor neurons; considered a primary center for mechanisms controlling conjugate horizontal gaze. SYN: n. nervi abducentis [TA] .
nuclei accessorii tractus optici [TA] SYN: accessory nuclei of optic tract.
accessory cuneate n. [TA] a cell group lateral to the cuneate n. that receives posterior-root fibers corresponding to the proprioceptive innervation of the arm and hand; it projects to the cerebellum by way of the cuneocerebellar tract, and can be considered the upper-extremity equivalent of the thoracic n.. SYN: n. cuneatus accessorius [TA] , external cuneate n., lateral cuneate n., Monakow n..
n. of accessory nerve a slender column of motor neurons extending longitudinally through central and lateral parts of the ventral horn of the upper six segments of the spinal cord, giving origin to the accessory nerve. SYN: n. nervi accessorii [TA] .
accessory olivary nuclei dorsal accessory olivary n., medial accessory olivary n..
accessory nuclei of optic tract [TA] small groups of neuron cell bodies located along the trajectory of optic fibers in the mesencephalon. These consist of the posterior n. [TA] (n. posterior [TA]), medial n. [TA] (n. medialis [TA]), and lateral n. [TA] (n. lateralis [TA]), which are also called the posterior, medial and lateral terminal nuclei. The connections of these nuclei, along with the n. of the optic tract, comprise the accessory optic system that appears to be concerned with retinal slip in specific directions. SYN: nuclei accessorii tractus optici [TA] .
n. accumbens [TA] the region of fusion between the head of the caudate n. and the putamen, covered on the ventral side by the olfactory tubercle. The former name n. accumbens septi (“a n. leaning against the septum”) refers to a medial, hook-shaped expansion of this anteroventral region of the striatum, which curves under the floor of the frontal horn of the lateral ventricle and ascends for some distance into the ventral half of the septal region. Composed of a pars lateralis [TA] (lateral part [TA] or core region [TAalt]) and a pars medialis [TA] (medial part [TA] or shell region [TAalt]).
n. acusticus obsolete term for the combined vestibular and cochlear nuclei.
n. alae cinereae SYN: posterior n. of vagus nerve.
ambiguus n. SYN: n. ambiguus.
n. ambiguus [TA] a very slender, longitudinal column of motor neurons in the ventrolateral medulla oblongata; its efferent fibers leave with the vagus and glossopharyngeal nerve and innervate the striated muscle fibers of the pharynx (including the musculus levator veli palatini) and the vocal cord muscles of the larynx. SYN: ambiguus n..
n. amygdalae SYN: amygdaloid body.
n. amygdalae basalis lateralis [TA] SYN: basolateral amygdaloid n..
n. amygdalae basalis medialis [TA] SYN: basomedial amygdaloid n..
n. amygdalae centralis [TA] SYN: central amygdaloid n..
n. amygdalae corticalis [TA] SYN: cortical amygdaloid n..
n. amygdalae interstitialis [TA] SYN: interstitial amygdaloid n..
n. amygdalae lateralis [TA] SYN: lateral amygdaloid n..
n. amygdalae medialis [TA] SYN: medial amygdaloid n..
amygdaloid n. SYN: amygdaloid body.
n. ansae lenticularis [TA] SYN: n. of the ansa lenticularis. See dorsal hypothalamic area.
n. of the ansa lenticularis [TA] See dorsal hypothalamic area. SYN: n. ansae lenticularis [TA] .
n. anterior [TA] See anterior horn.
anterior n. [TA] See anterior horn.
n. anterior corporis trapezoidei [TA] SYN: anterior n. of trapezoid body. See nuclei of trapezoid body.
nuclei anteriores thalami [TA] SYN: anterior nuclei of thalamus.
n. anterior hypothalami [TA] SYN: anterior hypothalamic n.. See anterior hypothalamic area.
anterior hypothalamic n. [TA] See anterior hypothalamic area. SYN: n. anterior hypothalami [TA] .
anterior interpositus n. [TA] one of two cerebellar nuclei interposed between the dentate and the fastigial nuclei. SYN: n. interpositus anterior [TA] .
anterior olfactory n. [TA] a n. located in the olfactory tract and prominent in microsmatic animals; receives input from the olfactory bulb and projects to the bulb, to other targets of olfactory fibers, and to its contralateral counterpart. SYN: n. olfactorius anterior [TA] .
anterior periventricular n. [TA] See anterior hypothalamic area. SYN: n. periventricularis ventralis [TA] .
anterior nuclei of thalamus [TA] collective term for three groups of nerve cells that together form the anterior thalamic tubercle: the anteroventral n. [TA], a relatively large n.; the anteromedial n. [TA]; and the anterodorsal n. [TA], a small (but large-celled) n.. These nuclei receive the mamillothalamic tract from the mamillary body, and additional afferents by way of the fornix; they project collectively to the cortex of the cingulate and parahippocampal gyrus. SYN: nuclei anteriores thalami [TA] .
anterior n. of trapezoid body [TA] See nuclei of trapezoid body. SYN: n. anterior corporis trapezoidei [TA] .
n. anterodorsalis [TA] SYN: anterodorsal n. of thalamus. See anterior nuclei of thalamus.
anterodorsal n. of thalamus SYN: n. anterodorsalis [TA] .anterior nuclei of thalamus.
n. anterolateralis [TA] See anterior horn.
anteromedial n. [TA] See anterior horn.
n. anteromedialis [TA] SYN: anteromedial n. of thalamus. See anterior nuclei of thalamus.
anteromedial n. of thalamus SYN: n. anteromedialis [TA] .anterior nuclei of thalamus.
n. anteroventralis [TA] SYN: anteroventral n. of thalamus. See anterior nuclei of thalamus.
anteroventral n. of thalamus SYN: n. anteroventralis [TA] .anterior nuclei of thalamus.
arcuate n. [TA] 1. SYN: n. arcuatus of intermediate hypothalamic area [TA] , posterior periventricular n. [TA] . SYN: arcuate n. of thalamus. 2. a cell group in the hypothalamus, located in the lowest part of the infundibulum adjacent to the median eminence. SYN: n. arcuatus of medulla oblongata [TA] . 3. a variable assembly of small cell groups, probably outlying components of the ponting nuclei, on the ventral and medial aspects of the pyramid in the medulla oblongata. SYN: n. arcuatus [TA] .
arcuate n. of thalamus the small ventral region of the ventral posteromedial n. of thalamus in which the fibers of the gustatory lemniscus and secondary trigeminal tracts terminate; it projects to the lower part of the postcentral gyrus of the cerebral cortex. SYN: arcuate n. (1) [TA] , n. arcuatus thalami, semilunar n. of Flechsig, thalamic gustatory n..
n. arcuatus [TA] SYN: arcuate n.. See intermediate hypothalamic area.
n. arcuatus of intermediate hypothalamic area [TA] SYN: arcuate n. (1) .
n. arcuatus of medulla oblongata [TA] SYN: arcuate n. (2) .
n. arcuatus thalami SYN: arcuate n. of thalamus.
auditory n. nuclei nervi vestibulocochlearis.
autonomic (visceral motor) nuclei nuclei located in the spinal cord (T1–L2, S2–S4) and in the brainstem (Edinger-Westphal n., superior and inferior salivatory nuclei, dorsal vagal n., and parts of the ambiguus n.) from which general visceral efferent preganglionic fibers arise; may be sympathetic (T1–L2) or parasympathetic (craniosacral); hypothalamic nuclei/areas function in concert with autonomic nuclei.
basal nuclei [TA] n. of the cerebral hemisphere that originally included the caudate and lenticular nuclei, the claustrum, and the amygdaloid body (complex); functionally the term basal nuclei now specifies the caudate and lenticular nuclei and adjacent cell groups having important connections therewith (subthalamic n.; substantia nigra and partes compacta and reticulata); amygdaloid complex now known to be part of the limbic system; SEE ALSO: basal ganglia, under ganglion. SYN: nuclei basales [TA] .
nuclei basales [TA] SYN: basal nuclei.
basal n. of Ganser a large group of large cells in the innominate substance, ventral to the lentiform n.. SYN: n. basalis of Ganser.
n. basalis of Ganser SYN: basal n. of Ganser.
basket n. nuclear structure that may be seen in Iodamoeba bütschlii cysts and occasionally in trophozoites; in stained preparations, fibrils may be seen running between the karyosome and the chromatin granules.
basolateral amygdaloid n. [TA] See amygdaloid body. SYN: n. amygdalae basalis lateralis [TA] .
basomedial amygdaloid n. [TA] See amygdaloid body. SYN: n. amygdalae basalis medialis [TA] .
Bechterew n. 1. See vestibular nuclei. 2. SYN: n. centralis tegmenti superior.
benzene n. the six conjugated carbon atoms of the benzene ring.
Blumenau n. the accessory cuneate n. [TA] of the medulla oblongata.
branchiomotor nuclei collective term for those motoneuronal nuclei of the brainstem (n. ambiguus, facial motor n., motor n. of the trigeminus) that develop from the branchiomotor column of the embryo and innervate striated muscle fibers (muscles of mastication, facial musculature, pharynx, and vocal cord muscles) associated with the branchial arches. SYN: special visceral efferent nuclei, special visceral motor nuclei.
Burdach n. SYN: cuneate n..
caeruleun n. [TA] a widely used term designating the locus ceruleus; See locus caeruleus.
n. caeruleus [TA] a shallow depression, blue in the fresh brain, lying laterally in the most rostral portion of the rhomboidal fossa near the cerebral aqueduct; it lies near the lateral wall of the fourth ventricle and consists of about 20,000 melanin-pigmented neuronal cell bodies whose norepinephrine-containing axons have a remarkably wide distribution in the cerebral cortex, dorsal thalamus, amygdaloid complex and hippocampus, mesencephalic tegmentum, cerebellar nuclei and cortex, various nuclei in the pons and medulla, and the gray matter of the spinal cord.
n. campi dorsalis [TA] SYN: n. of dorsal field. See nuclei of perizonal fields.
n. campi medialis [TA] SYN: n. of medial field. See nuclei of perizonal fields.
nuclei camporum perizonalium [TA] SYN: nuclei of perizonal fields.
n. campi ventralis [TA] SYN: n. of ventral field. See nuclei of perizonal fields.
caudal pontine reticular n. [TA] See reticular nuclei of pons. SYN: n. reticularis pontis caudalis [TA] .
caudate n. [TA] an elongated curved mass of gray matter, consisting of an anterior thick portion, the caput [TA] or head [TA], which protrudes into the anterior horn of the lateral ventricle, a portion extending along the floor of the body of the lateral ventricle, known as the corpus [TA] or body [TA], and an elongated curved thin portion, the cauda [TA] or tail [TA], which curves downward, backward, and forward in the temporal lobe in the dorsolateral wall of the lateral ventricle. SYN: n. caudatus [TA] , caudate (2) , caudatum.
n. caudatus [TA] SYN: caudate n..
central n. [TA] See anterior horn.
central amygdaloid n. [TA] See amygdaloid body. SYN: n. amygdalae centralis [TA] .
n. centralis [TA] See anterior horn.
n. centralis lateralis [TA] SYN: central lateral n. of thalamus.
n. centralis tegmenti superior one of the nuclei raphes. SYN: Bechterew n. (2) .
central lateral n. of thalamus [TA] the most lateral of the intralaminar nuclei of the thalamus. SYN: n. centralis lateralis [TA] .
centromedian n. [TA] a large, lentil-shaped cell group, the largest and most caudal of the intralaminar nuclei, located within the lamina medullaris interna of the thalamus between the mediodorsal n. and ventrobasal n.; so called by Luys because of its prominent appearance on frontal sections midway between the anterior and posterior pole of the human thalamus. The n. receives numerous fibers from the internal segment of the globus pallidus by way of the thalamic fasciculus, ansa lenticularis, and lenticular fasciculus as well as projections from area 4 of the motor cortex; its major efferent connection is with the putamen although collaterals reach broad areas of the cerebral cortex. SYN: n. centromedianus [TA] , centre médian de Luys, centrum medianum.
n. centromedianus [TA] SYN: centromedian n..
cerebellar nuclei [TA] collective term for the dentate, globosus, and emboliform nuclei, and the tectal and fastigial nuclei of the cerebellum. SYN: nuclei cerebelli [TA] .
nuclei cerebelli [TA] SYN: cerebellar nuclei.
Clarke n. SYN: posterior thoracic n..
cochlear nuclei [TA] SYN: nuclei cochleares.
nuclei cochleares [TA] the n. cochlearis posterior [TA] (posterior cochlear n. [TA] or dorsal cochlear n. [TAalt]) and n. cochlearis anterior [TA] (anterior cochlear n. [TA] or ventral cochlear n. [TAalt]) are located on the dorsal and lateral surface of the inferior cerebellar peduncle, in the floor of the lateral recess of the rhomboid fossa. The anterior cochlear nuclei may be divided into an anterior part [TA] (pars anterior [TA]) and a posterior part [TA] (pars posterior [TA]); they receive the incoming fibers of the cochlear part of the vestibulocochlear nerve and are the major source of origin of the lateral lemniscus or central auditory pathway. SYN: cochlear nuclei [TA] , nuclei nervi cochlearis.
n. cochlearis anterior [TA] See nuclei cochleares.
n. cochlearis posterior [TA] See nuclei cochleares.
nuclei colliculi inferioris [TA] SYN: nuclei of inferior colliculus.
n. commissurae posterioris [TA] SYN: n. of posterior commissure.
convergence n. of Perlia SYN: Perlia n..
nuclei corporis geniculati medialis [TA] SYN: medial geniculate nuclei.
nuclei corporis mamillaris SYN: nuclei of mammillary body.
n. corporis mammillaris lateralis [TA] SYN: nuclei of mammillary body.
n. corporis mammillaris medialis [TA] SYN: nuclei of mammillary body.
nuclei corporis trapezoidei [TA] SYN: nuclei of trapezoid body.
cortical amygdaloid n. [TA] See amygdaloid body. SYN: n. amygdalae corticalis [TA] .
nuclei of cranial nerves groups of nerve cells associated with the cranial nerves either as motor nuclei (nuclei originis) or sensory nuclei (nuclei terminationis). SYN: n. nervi cranialis [TA] .
cuneate n. [TA] the larger Burdach n.; one of the three nuclei of the posterior column of the spinal cord; located near the dorsal surface of the medulla oblongata at and below the level of the obex, the n. receives posterior root fibers corresponding to the sensory innervation of the arm and hand of the same side; it consists of a pars centralis [TA] (central part [TA], cell nest region [TAalt]) and a pars rostralis [TA] (rostral part [TA], shell region [TAalt]; together with its medial companion, the gracile n., it is the major source of origin of the medial lemniscus. SYN: n. cuneatus pars, rostralis [TA] , n. cuneatus, pars centralis [TA] , n. cuneatus [TA] , Burdach n., n. funiculi cuneati, n. of cuneate fasciculus.
n. of cuneate fasciculus SYN: cuneate n..
n. cuneatus [TA] SYN: cuneate n..
n. cuneatus accessorius [TA] SYN: accessory cuneate n..
n. cuneatus, pars centralis [TA] SYN: cuneate n..
n. cuneatus pars, rostralis [TA] SYN: cuneate n..
cuneiform n. [TA] See reticular nuclei of mesencephalon. SYN: n. cuneiformis [TA] .
n. cuneiformis [TA] SYN: cuneiform n.. See reticular nuclei of mesencephalon.
n. of Darkschewitsch an ovoid cell group in the ventral central gray substance rostral to the oculomotor n., receiving fibers from the vestibular nuclei by way of the medial longitudinal fasciculus; projections are not known, although some cross in the posterior commissure.
Deiters n. See vestibular nuclei.
dentate n. of cerebellum the most lateral and largest of the cerebellar nuclei; it receives the axons of Purkinje cells from the lateral area of the cerebellar cortex (so-called neocerebellum) and input via collaterals of cerebellar afferent fibers en route to the overlying cerebellar cortex; together with the more medially located globosus and emboliform nuclei, it is the major source of fibers composing the massive superior cerebellar peduncle or brachium conjunctivum. SYN: n. dentatus [TA] , n. lateralis cerebelli&star, corpus dentatum, dentatum.
n. dentatus [TA] SYN: dentate n. of cerebellum.
descending n. of the trigeminus SYN: spinal n. of trigeminal nerve.
diploid n. a n. containing the diploid or normal double complement of chromosomes for one somatic cell.
dorsal n. [TA] See medial geniculate nuclei. SYN: n. dorsalis hypothalami [TA] , n. dorsalis [TA] .
dorsal accessory olivary n. a detached part of the olivary n. dorsal to the latter's main body. SYN: n. olivaris accessorius posterior [TA] , posterior accessory olivary n. [TA] .
n. dorsales thalami [TA] SYN: dorsal n. of thalamus.
n. of dorsal field [TA] See nuclei of perizonal fields. SYN: n. campi dorsalis [TA] .
n. dorsalis [TA] SYN: dorsal n.. See medial geniculate nuclei.
n. dorsalis corporis geniculati lateralis [TA] SYN: dorsal lateral geniculate n..
n. dorsalis corporis trapezoidei SYN: dorsal n. of trapezoid body.
n. dorsalis hypothalami [TA] SYN: dorsal n.. See intermediate hypothalamic area.
n. dorsalis lateralis [TA] SYN: lateral dorsal n.. See dorsal n. of thalamus.
n. dorsalis nervi vagi posterior n. of vagus nerve.
dorsal lateral geniculate n. [TA] main division of the lateral geniculate body; consists of two magnocellular layers [TA] (strata magnocellularia [TA]) and four parvocellular layers [TA] (strata parvocellularia [TA]) and serves as a processing station in the major pathway from the retina to the cerebral cortex, receiving fibers from the optic tract and giving rise to the geniculocalcarine radiation to the visual cortex in the occipital lobe. SYN: n. dorsalis corporis geniculati lateralis [TA] .
dorsal motor n. of vagus SYN: posterior n. of vagus nerve.
dorsal premammillary n. [TA] See posterior hypothalamic area. SYN: n. premammillaris dorsalis [TA] .
dorsal septal n. [TA] See septal area.
dorsal n. of thalamus one of the major subdivisions of the thalamus; the composite dorsal n. includes the n. lateralis anterior or dorsalis, n. lateralis intermedius, n. lateralis posterior, and pulvinar; together, these cell groups form most of the free dorsal surface of the posterior half of the thalamus and project to a very large region of parietal, occipitoparietal, and temporal cortex; its afferent connections are largely obscure, but the n. lateralis posterior and the pulvinar receive a projection from the superior colliculus. SYN: n. dorsales thalami [TA] .
dorsal thoracic n. posterior thoracic n..
dorsal n. of trapezoid body a term sometimes used to designate t6 superior olivary n. located ventrolaterally in the lower pontine tegmentum, immediately dorsal to the trapezoid body; the n. receives fibers from both the ipsilateral and contralateral cochlear nuclei and contributes fibers to the lateral (auditory) lemniscus of both sides. It is believed to be prominently involved in the function of spatial localization of sound. SYN: n. dorsalis corporis trapezoidei, oliva superior, superior olive.
dorsal vagal n. SYN: posterior n. of vagus nerve.
dorsal n. of vagus SYN: posterior n. of vagus nerve.
dorsolateral n. See anterior horn.
dorsomedial n. [TA] See dorsal hypothalamic area. SYN: n. dorsomedialis [TA] .
dorsomedial hypothalamic n. SYN: dorsomedial n. of hypothalamus.
dorsomedial n. of hypothalamus [TA] an oval cluster of cells located dorsal to the ventromedial hypothalamic n.. SYN: n. dorsomedialis hypothalami [TA] , dorsomedial hypothalamic n..
n. dorsomedialis [TA] SYN: dorsomedial n.. See intermediate hypothalamic area.
n. dorsomedialis hypothalami [TA] SYN: dorsomedial n. of hypothalamus.
droplet nuclei particles 1–10 μm in diameter, implicated in spread of airborne infection; the dried residue formed by evaporation of droplets coughed or sneezed into the atmosphere or by aerosolization of infective material.
Edinger-Westphal n. a small group of preganglionic parasympathetic motor neurons in the midline near the rostral pole of the oculomotor n. of the midbrain; the axons of these motor neurons leave the brain with the oculomotor nerve and synapse on the cells of the ciliary ganglion which in turn innervate the sphincter muscle of the pupil and ciliary muscle. Destruction of this n. or its efferent fibers causes maximal paralytic dilation of the pupil; also demonstrated to project fibers to lower levels of the brainstem and all spinal levels. SYN: visceral nuclei of oculomotor nerve [TA] .
emboliform n. one of two cerebellar nuclei interposed between the dentate and the fastigial nuclei; a small wedge-shaped n. in the central white substance of the cerebellum just internal to the hilus of the dentate n.; receives axons of Purkinje cells of the intermediate area of the cerebellar cortex; axons of these cells exit the cerebellum via the superior cerebellar peduncle. SYN: n. emboliformis&star, embolus (2) .
n. emboliformis emboliform n..
endolemniscal n. [TA] small clusters of neuron cell bodies located on the lateral aspect of the medial lemniscus in the medulla oblongata, or insinuated within the fascicles of this fiber bundle. SYN: n. endolemniscalis [TA] .
n. endolemniscalis [TA] SYN: endolemniscal n..
endopeduncular n. [TA] See dorsal hypothalamic area. SYN: n. endopeduncularis [TA] .
n. endopeduncularis [TA] SYN: endopeduncular n.. See dorsal hypothalamic area.
external cuneate n. SYN: accessory cuneate n..
facial n. a group of motor neurons located in the ventrolateral region of the lower pontine tegmentum and innervating the facial muscles, the stapedius muscle in the middle ear, the posterior limb of the musculus digastricus, and the stylohyoid muscle. SYN: motor n. of facial nerve [TA] , n. nervi facialis [TA] , facial motor n., n. facialis.
n. facialis SYN: facial n..
facial motor n. SYN: facial n..
n. fasciculi gracilis SYN: gracile n..
fastigial n. [TA] the most medial of the cerebellar nuclei, lying medial to the interpositus n., near the midline, in the white matter underneath the vermis of the cerebellar cortex. It receives the axons of Purkinje cells from all parts of the vermis. Its major projection is to the vestibular nuclei and medullary reticular formation. SYN: n. fastigii [TA] , n. medialis cerebelli&star, fastigatum, n. tecti, roof n., tectal n..
n. fastigii [TA] SYN: fastigial n..
filiform n. SYN: paraventricular n. [TA] of hypothalamus.
n. filiformis SYN: paraventricular n. [TA] of hypothalamus.
n. funiculi cuneati SYN: cuneate n..
n. funiculi gracilis SYN: gracile n..
gametic n. SYN: micronucleus (2) .
n. gelatinosus SYN: n. pulposus.
gelatinous n. SYN: n. pulposus.
geniculatus lateralis n. See lateral geniculate body.
germ n. SYN: micronucleus (2) .
n. gigantocellularis medullae oblongatae [TA] SYN: gigantocellular n. of medulla oblongata.
gigantocellular n. of medulla oblongata [TA] one of the three major nuclei of the reticular formation of the brainstem; its small ventromedial portion is designated as pars alpha [TA]. SYN: n. gigantocellularis medullae oblongatae [TA] .
n. globosus globosus n..
globosus n. one of two cerebellar nuclei interposed between the fastigial and the dentate nuclei; a group of two or three small masses of gray substance in the white central core of the cerebellum, medial to the emboliform n.; receives axons of Purkinje cells of the intermediate area of the cerebellar cortex; axons of these cells exit the cerebellum via the superior cerebellar peduncle. SYN: n. globosus&star, spherical n..
n. of Goll SYN: gracile n..
gonad n. SYN: micronucleus (2) .
gracile n. [TA] the medial one of the three nuclei of the dorsal column, the remaining two being the cuneate n. and the accessory cuneate n., which corresponds to the clava; it can be divided into a pars centralis [TA] (central part [TA]), cell nest region [TAalt]), a pars rostralis [TA] (rostral part [TA], shell region [TAalt]), and subnucleus rostrodorsalis [TA] (rostrodorsal subnucleus [TA], cell group z [TAalt]; it receives dorsal-root fibers conveying sensory innervation of the leg, and lower trunk, and projects, by way of the medial lemniscus, to the ventral posterolateral posterior n. of the thalamus. SYN: n. gracilis [TA] , n. fasciculi gracilis, n. funiculi gracilis, n. of Goll.
n. gracilis [TA] SYN: gracile n..
Gudden tegmental nuclei SYN: tegmental nuclei.
gustatory n. rhombencephalic gustatory n., thalamic gustatory n..
habenular nuclei the gray matter of the habenula, composed of a small-celled medial habenular n. [TA] (n. habenularis medialis [TA]) and a large-celled lateral habenular n. [TA] (n. habenularis lateralis [TA]); both nuclei receive fibers from basal forebrain regions (septum, basal n., lateral preoptic n.); the lateral habenular n. receives an additional projection from the medial segment of the globus pallidus. Both nuclei project by way of the retroflex fasciculus to the interpeduncular n. and a medial zone of the midbrain tegmentum. SYN: ganglion habenulae.
n. habenularis lateralis [TA] SYN: lateral habenular n.. See habenular nuclei.
n. habenularis medialis [TA] SYN: medial habenular n.. See habenular nuclei.
hypoglossal n. the motor n. innervating the intrinsic and four of the five extrinsic muscles of the tongue; it is located in the medulla oblongata near the midline, immediately beneath the floor of the inferior recess of the rhomboid fossa. SYN: n. nervi hypoglossi [TA] , n. of hypoglossal nerve [TA] .
n. of hypoglossal nerve [TA] SYN: hypoglossal n..
nuclei of inferior colliculus [TA] the nerve cell groups composing the colliculus inferior consisting of a central n. [TA] (n. centralis [TA]), an external n. [TA] (n. externus [TA] or n. lateralis [TAalt]), and a pericentral n. [TA] (n. pericentralis [TA]). SYN: nuclei colliculi inferioris [TA] .
inferior olivary n. a large aggregate of small densely packed nerve cells consisting of medial and dorsal accessory olivary nuclei and a principal olivary n. that is arranged in folded laminae shaped like a purse with the opening (hilum) directed medially. It corresponds in position to the oliva, projects to all parts of the contralateral half of the cerebellar cortex by way of the olivocerebellar tract, and is the only source of cerebellar climbing fibers. Its afferent connections include fibers from the spinal cord, dentate n., and motor cortex, but its major input appears to be the central tegmental tract originating from multiple nuclei at midbrain levels. SYN: n. olivaris inferior.
inferior salivary n. SYN: inferior salivatory n..
inferior salivatory n. [TA] a group of preganglionic parasympathetic motor neurons located in the reticular formation of the medulla oblongata dorsal to the n. ambiguus; its axons leave the brain with the glossopharyngeal nerve and govern secretion from the parotid gland by the intermediary of the ganglion oticum; cells of the inferior and superior n. are scattered and overlapping in lateral regions of the reticular formation. SYN: n. salivatorius inferior [TA] , inferior salivary n..
inferior vestibular n. [TA] n. vestibularis inferior. SEE ALSO: vestibular nuclei. SYN: n. vestibularis inferior [TA] .
intercalated n. [TA] a small collection of nerve cells in the medulla oblongata lying lateral to the hypoglossal n.. SYN: n. intercalatus [TA] , Staderini n..
n. intercalatus [TA] SYN: intercalated n..
intermediolateral n. [TA] the cell column that forms the lateral horn of the spinal cord's gray matter. Extending from the first thoracic through the second lumbar segment, the column contains the autonomic motor neurons that give rise to the preganglionic fibers of the sympathetic system. SYN: n. intermediolateralis [TA] , intermediolateral cell column of spinal cord.
n. intermediolateralis [TA] SYN: intermediolateral n..
intermediomedial n. [TA] a small group of scattered visceral motor neurons immediately ventral to the thoracic n. in the thoracic and upper two lumbar segments of the spinal cord; considered to receive visceral afferent fibers at all spinal levels. SYN: n. intermediomedialis [TA] .
n. intermediomedialis [TA] SYN: intermediomedial n..
interpeduncular n. [TA] a median, unpaired, ovoid cell group at the base of the midbrain tegmentum between the cerebral peduncles; it receives the retroflex fasciculus from the habenula and projects to the raphe region (raphe nuclei) and periaqueductal gray substance of the midbrain. SYN: n. interpeduncularis [TA] , ganglion isthmi, Gudden ganglion, intercrural ganglion, interpeduncular ganglion.
n. interpeduncularis [TA] SYN: interpeduncular n..
n. interpositus SYN: interpositus n..
interpositus n. collective term denoting the globosus n. and emboliform n. of the cerebellum. SYN: n. interpositus.
n. interpositus anterior [TA] SYN: anterior interpositus n. .
n. interpositus posterior [TA] SYN: posterior interpositus n..
interstitial n. [TA] a group of widely spaced, medium-sized neurons in the dorsomedial region of the upper mesencephalic tegmentum, immediately lateral to the n. of Darkschewitsch; together with the latter, the interstitial n. is closely associated with the medial longitudinal fasciculus, via which it receives fibers from the vestibular nuclei and projects crossed fibers via the posterior commissure to the oculomotor n.; also projects fibers to all spinal levels. It is believed to be involved in the integration of head and eye movements, particularly eye movements of a vertical or oblique nature. SYN: n. interstitialis [TA] , interstitial n. of Cajal.
interstitial amygdaloid n. [TA] See amygdaloid body. SYN: n. amygdalae interstitialis [TA] .
interstitial nuclei of anterior hypothalamus [TA] See anterior hypothalamic area. SYN: nuclei interstitiales hypothalami anterioris [TA] .
interstitial n. of Cajal SYN: interstitial n..
n. interstitiales fasciculi longitudinalis medialis [TA] SYN: interstitial n. of medial longitudinal fasciculus.
nuclei interstitiales hypothalami anterioris [TA] SYN: interstitial nuclei of anterior hypothalamus. See anterior hypothalamic area.
n. interstitialis [TA] SYN: interstitial n..
interstitial n. of medial longitudinal fasciculus [TA] small groups of cells located laterally adjacent to the medial longitudinal fasciculus in the area of the oculomotor n.; involved in eye movement through connections with the oculomotor and trochlear nuclei. These connections are primarily ipsilateral but have a bilateral component. SYN: n. interstitiales fasciculi longitudinalis medialis [TA] .
nuclei intralaminares thalami [TA] SYN: intralaminar nuclei of thalamus.
intralaminar nuclei of thalamus [TA] collective term denoting several cell groups embedded in the internal medullary lamina of the thalamus: the central lateral n. [TA], paracentral n. [TA] (n. paracentralis [TA]), the central medial n. [TA] (n. centralis medialis [TA]), the centromedian n., and the parafascicular n. [TA] (n. parafascicularis [TA]). The central lateral and paracentral receive afferents from the cerebral cortex, brainstem, reticular formation, cerebellum, and spinal cord, and project more or less diffusely to large regions of the frontal and parietal cortex. The centromedian n. receives input from the internal segment of the globus pallidus and motor cortex and projects to the striatum and motor cortex. SEE ALSO: centromedian n.. SYN: nuclei intralaminares thalami [TA] .
Klein-Gumprecht shadow nuclei shadow nuclei in degenerating lymphoidocytes and macrolymphocytes in leukemia.
lateral n. [TA] See accessory nuclei of optic tract. SYN: n. lateralis [TA] .
lateral amygdaloid n. [TA] See amygdaloid body. SYN: n. amygdalae lateralis [TA] .
lateral cervical n. [TA] diffusely arranged n. located in the dorsal portions of the lateral funiculus in about cervical levels C1–C3; synaptic station for the spinocervicothalamic tract.
lateral cuneate n. SYN: accessory cuneate n..
lateral dorsal n. [TA] See dorsal n. of thalamus. SYN: n. dorsalis lateralis [TA] .
lateral geniculate n. See dorsal lateral geniculate n..
n. of lateral geniculate body See dorsal lateral geniculate n..
lateral habenular n. [TA] See habenular nuclei. SYN: n. habenularis lateralis [TA] .
n. lateralis [TA] SYN: lateral n.. See accessory nuclei of optic tract.
n. lateralis cerebelli dentate n. of cerebellum.
n. lateralis corporis trapezoidei [TA] SYN: lateral n. of trapezoid body. See nuclei of trapezoid body.
n. lateralis medullae oblongatae SYN: lateral n. of medulla oblongata.
n. lateralis posterior [TA] SYN: lateral posterior n.. See dorsal n. of thalamus.
nuclei of lateral lemniscus [TA] a substantial cell mass embedded in the lateral lemniscus, immediately below the latter's entry into the inferior colliculus; may be divided into a posterior n. of lateral lemniscus [TA] (dorsal n. of lateral lemniscus [TAalt], n. posterior lemnisci lateralis [TA]), an intermediate n. of lateral lemniscus [TA] (n. intermedius lemnisci lateralis [TA]), and an anterior n. of lateral lemniscus [TA] (n. anterior lemnisci lateralis [TA], ventral n. of lateral lemniscus [TAalt]); the n. represents a synaptic way-station for part of the fibers of the lateral lemniscus. SYN: nuclei lemnisci lateralis [TA] .
lateral n. of mammillary body [TA] See posterior hypothalamic area.
lateral n. of medulla oblongata SYN: lateral reticular n.. SYN: n. lateralis medullae oblongatae.
n. of the lateral olfactory tract [TA] See amygdaloid body. SYN: n. tractus olfactorii lateralis [TA] .
lateral parabrachial n. a cell group located lateral to the brachium conjunctivum in rostral regions of the pons; may be divided into a pars lateralis [TA] (lateral part [TA]), a pars medialis [TA] (medial part [TA]), pars posterior [TA] (posterior part [TA]), and a pars anterior [TA] (anterior part [TA]). SEE ALSO: parabrachial nuclei. SYN: n. parabrachialis lateralis [TA] .
lateral pericuneate n. [TA] a small flattened group of neuron cell bodies located ventrolateral to the cuneate n. and insinuated between the cuneate fasciculus and accessory cuneate n. and the spinal tract of the trigeminal nerve. SYN: n. pericuneatus lateralis [TA] .
lateral posterior n. [TA] See dorsal n. of thalamus. SYN: n. lateralis posterior [TA] .
lateral preoptic n. [TA] a vaguely defined group of nerve cells in the lateral zone of the preoptic region. SEE ALSO: anterior hypothalamic area. SYN: n. preopticus lateralis [TA] .
lateral reticular n. group of cells in the medulla oblongata located between the inferior olive and the descending trigeminal n. and tract; composed of a magnocellular part [TA] (pars magnocellularis [TA]), a parvocellular part [TA] (pars parvocellularis [TA]), and a subtrigeminal part [TA] (pars subtrigeminalis [TA]); receives fibers from the spinal and motor cortex and projects to the cerebellum. SYN: lateral n. of medulla oblongata.
lateral septal n. [TA] See septal area.
lateral superior olivary n. [TA] See superior olivary n.. SYN: n. olivaris superior lateralis [TA] .
lateral n. of thalamus See dorsal n. of thalamus.
lateral n. of trapezoid body [TA] See nuclei of trapezoid body. SYN: n. lateralis corporis trapezoidei [TA] .
lateral tuberal nuclei [TA] See intermediate hypothalamic area.
lateral vestibular n. [TA] n. vestibularis lateralis. See vestibular nuclei. SYN: n. vestibularis lateralis [TA] .
nuclei lemnisci lateralis [TA] SYN: nuclei of lateral lemniscus.
n. of lens [TA] SYN: n. lentis.
lenticular n.
n. lentiformis [TA] SYN: lentiform n..
n. lentis [TA] the core or inner dense portion of the lens of the eye. SYN: n. of lens [TA] .
n. of Luys SYN: subthalamic n..
nuclei of mammillary body located in the posterior hypothalamic area, this group of nuclei consists of a large-celled lateral n. of the mammillary body and larger medial nuclei of the mammillary body, dorsal and ventral premammillary nuclei, and supramammillary n.; the first two form the elevation seen on the ventral aspect of the diencephalon, the mammillary body. SYN: n. corporis mammillaris lateralis [TA] , n. corporis mammillaris medialis [TA] , nuclei corporis mamillaris.
n. masticatorius SYN: motor n. of trigeminal nerve.
masticatory n. SYN: motor n. of trigeminal nerve.
medial n. [TA] See accessory nuclei of optic tract. SYN: n. medialis [TA] .
medial accessory olivary n. [TA] a detached part of the olivary n. medial to the latter's main body, against the lateral side of the medial lemniscus and pyramidal tract. SYN: n. olivaris accessorius medialis [TA] .
medial amygdaloid n. [TA] See amygdaloid body. SYN: n. amygdalae medialis [TA] .
medial central n. of thalamus a small cell group in the interthalamic adhesion of the thalamus, occupying the midline region of the internal medullary lamina, between the left and the right paracentral n.. SYN: n. medialis centralis thalami.
medial dorsal n. [TA] of thalamus a large, composite cell group in the dorsomedial region of the thalamus having reciprocal connections with the entire extent of the frontal cortex anterior to the motor cortex (area 4) and premotor cortex (area 6). The afferent connections of the medial dorsal n. also include projections from the olfactory cortex and amygdala. Composed of a pars parvocellularis lateralis [TA] (lateral n. [TA] or parvocellular n. [TAalt]), a pars magnocellularis medialis [TA] (medial n. [TA] or magnocellular n. [TAalt]), and a pars paralaminaris [TA] (paralaminar part [TA] or pars laminaris [TAalt]). SYN: mediodorsal n., n. medialis thalami, n. mediodorsalis.
nuclei mediales thalami [TA] SYN: medial nuclei of thalamus.
n. of medial field [TA] See nuclei of perizonal fields. SYN: n. campi medialis [TA] .
medial geniculate nuclei groups of cell bodies that function as the last of a series of processing stations along the auditory conduction pathway to the cerebral cortex, receiving the brachium of the inferior colliculus and giving rise to the auditory radiation to the auditory cortex in the superior temporal gyrus. SYN: nuclei corporis geniculati medialis [TA] , n. of medial geniculate body.
medial geniculate nuclei [TA] nerve cells that collectively form a surface elevation, the medial geniculate body; they comprise a ventral principal n. [TA], a dorsal n. [TA], and a small medial magnocellular n.; relay of auditory input to auditory cortex
n. of medial geniculate body SYN: medial geniculate nuclei.
medial habenular n. [TA] See habenular nuclei. SYN: n. habenularis medialis [TA] .
n. medialis [TA] SYN: medial n.. See accessory nuclei of optic tract.
n. medialis centralis thalami SYN: medial central n. of thalamus.
n. medialis cerebelli fastigial n..
n. medialis corporis trapezoidei [TA] SYN: medial n. of trapezoid body. See nuclei of trapezoid body.
n. medialis magnocellularis SYN: medial magnocellular n.. See medial geniculate nuclei.
n. medialis thalami SYN: medial dorsal n. [TA] of thalamus.
medial magnocellular n. See medial geniculate nuclei. SYN: n. medialis magnocellularis.
medial parabrachial n. [TA] a cell group located medial to the brachium conjunctivum in rostral areas of the pons; may be divided into a pars medialis [TA] (medial part [TA]) and a pars lateralis [TA] (lateral part [TA]). SEE ALSO: parabrachial nuclei. SYN: n. parabrachialis medialis [TA] .
medial pericuneate n. [TA] a small group of neuron cell bodies located immediately ventromedial to the cuneate n., insinuated in a diffuse layer of cells, the pericuneate matrix. SYN: n. pericuneatus medialis [TA] .
medial preoptic n. [TA] a group of nerve cells forming the medial zone of the preoptic region. SYN: n. preopticus medialis [TA] .
medial septal n. [TA] See septal area.
medial superior olivary n. [TA] See superior olivary n.. SYN: n. olivaris superior medialis [TA] .
medial nuclei of thalamus [TA] collective group of cells comprising the large medial dorsal n. (or dorsomedial n.) and its subdivisions (lateral n. or parvocellular n., medial n. or magnocellular n., paralaminar part or pars paralaminaris) and the medial ventral n. [TA] (n. medioventralis [TA]). SYN: nuclei mediales thalami [TA] .
medial n. of trapezoid body [TA] See nuclei of trapezoid body. SYN: n. medialis corporis trapezoidei [TA] .
medial ventral n. [TA] See medial nuclei of thalamus. SYN: n. medioventralis [TA] .
medial vestibular n. [TA] See VESTIBULAR NUCLEI51. SYN: n. vestibularis medialis [TA] .
median preoptic n. [TA] See anterior hypothalamic area. SYN: n. preopticus medianus [TA] .
mediodorsal n. SYN: medial dorsal n. [TA] of thalamus.
n. mediodorsalis SYN: medial dorsal n. [TA] of thalamus.
n. medioventralis [TA] SYN: medial ventral n.. See medial nuclei of thalamus.
mesencephalic n. of trigeminal nerve [TA] a long, narrow plate of unipolar neurons extending throughout the length of the midbrain, in and along the lateral angle of the central gray substance. The n. is the single known instance of primary sensory neurons enclosed in the central nervous system instead of in a peripheral sensory ganglion. Its peripheral axonal processes pass with the trigeminal nerve, give collaterals to the trigeminal motor n., and terminate in the muscles of mastication. SYN: n. mesencephalicus nervi trigemini [TA] .
n. mesencephalicus nervi trigemini [TA] SYN: mesencephalic n. of trigeminal nerve.
Monakow n. SYN: accessory cuneate n..
motor nuclei SYN: nuclei of origin.
motor n. of facial nerve [TA] SYN: facial n..
n. motorius nervi trigemini [TA] SYN: motor n. of trigeminal nerve.
motor n. of trigeminal nerve [TA] a group of motor neurons innervating the muscles of mastication (masseter, temporalis, and internal and external pterygoid muscles) and the musculi tensor tympani and tensor veli palatini. The n. lies in the upper pontine tegmentum medial to the principal sensory n. of the trigeminal nerve. SYN: n. motorius nervi trigemini [TA] , masticatory n., motor n. of trigeminus, n. masticatorius.
motor n. of trigeminus SYN: motor n. of trigeminal nerve.
n. nervi abducentis [TA] SYN: abducens n..
n. nervi accessorii [TA] SYN: n. of accessory nerve.
nuclei nervi cochlearis SYN: nuclei cochleares.
n. nervi cranialis [TA] SYN: nuclei of cranial nerves.
n. nervi facialis [TA] SYN: facial n..
n. nervi hypoglossi [TA] SYN: hypoglossal n..
n. nervi oculomotorii [TA] SYN: oculomotor n..
n. nervi phrenici [TA] SYN: n. of phrenic nerve.
n. nervi trochlearis [TA] SYN: n. of trochlear nerve.
nuclei nervi vestibulocochlearis SYN: vestibulocochlear nuclei.
n. niger SYN: substantia nigra.
oculomotor n. the composite group of motor neurons innervating all of the external eye muscles except the musculus rectus lateralis and musculus obliquus superior, and including the musculus levator palpebrae superioris; the most rostral component of the n. is the Edinger-Westphal n., which innervates the musculi sphincter pupillae and ciliaris via the ciliary ganglion. The oculomotor n. lies in the rostral half of the midbrain, near the midline in the most ventral part of the central gray substance; fibers of the medial longitudinal fasciculus form its lateral borders. SYN: n. nervi oculomotorii [TA] , n. of oculomotor nerve [TA] .
n. of oculomotor nerve [TA] SYN: oculomotor n..
n. olfactorius anterior [TA] SYN: anterior olfactory n..
n. olivaris accessorius medialis [TA] SYN: medial accessory olivary n..
n. olivaris accessorius posterior [TA] SYN: dorsal accessory olivary n..
n. olivaris inferior SYN: inferior olivary n..
n. olivaris principalis [TA] SYN: principal olivary n..
n. olivaris superior [TA] SYN: superior olivary n..
n. olivaris superior lateralis [TA] SYN: lateral superior olivary n.. See superior olivary n..
n. olivaris superior medialis [TA] SYN: medial superior olivary n.. See superior olivary n..
Onuf n. a group of small somatic motor neurons in the ventral horn of the spinal cord at sacral 2 level that innervate the vesicorectal sphincters, that is, the external anal and the urethral sphincter; Onuf n. has been identified in the cat, dog, and human. SYN: n. of pudendal nerve [TA] . [Onufrowicz, Wladislaus, Swiss anatomist.]
oral pontine reticular n. [TA] See reticular nuclei of pons. SYN: n. reticularis pontis oralis [TA] .
nuclei of origin collections of motor neurons (forming a continuous column in the spinal cord, discontinuous in the medulla and pons) giving origin to the spinal and cranial motor nerves. SYN: n. originis [TA] , motor nuclei.
n. originis [TA] SYN: nuclei of origin.
parabigeminal n. [TA] a group of neuron cell bodies located in the lateral position of the midbrain in the area of spinothalamic fibers; ventrolaterally adjacent to the inferior colliculus with which it has interconnections. SYN: n. parabigeminalis [TA] .
n. parabigeminalis [TA] SYN: parabigeminal n..
parabrachial nuclei [TA] the cell groups flanking the brachium conjunctivum at levels immediately caudal to the inferior colliculus; they serve as way-stations in the pathways ascending from the n. of solitary tract to the thalamus and hypothalamus and receive afferent fibers from the hypothalamus and amygdaloid body. SYN: nuclei parabrachiales [TA] .
nuclei parabrachiales [TA] SYN: parabrachial nuclei.
n. parabrachialis lateralis [TA] SYN: lateral parabrachial n..
n. parabrachialis medialis [TA] SYN: medial parabrachial n..
n. paracentralis thalami [TA] SYN: paracentral n. of thalamus.
paracentral n. of thalamus [TA] one of the intralaminar nuclei of the thalamus, medial to the central lateral n.. SYN: n. paracentralis thalami [TA] .
paralemniscal n. [TA] See reticular nuclei of pons. SYN: n. paralemniscalis [TA] .
n. paralemniscalis [TA] SYN: paralemniscal n.. See reticular nuclei of pons.
paramedial reticular n. [TA] See reticular nuclei of pons.
paranigral n. [TA] a small cell cluster located in the ventromedial regions of the midbrain and insinuated between the medial aspect of the substantia nigra and the interpeduncular n.. SYN: n. paranigralis [TA] .
n. paranigralis [TA] SYN: paranigral n..
parapeduncular n. [TA] See reticular nuclei of mesencephalon. SYN: n. parapeduncularis [TA] .
n. parapeduncularis [TA] SYN: parapeduncular n.. See reticular nuclei of mesencephalon.
paraventricular n. [TA] See anterior hypothalamic area.
n. paraventricularis hypothalami SYN: paraventricular n. [TA] of hypothalamus.
paraventricular n. [TA] of hypothalamus a triangular group of large magnocellular neurons in the periventricular zone of the anterior half of the hypothalamus. The cells of the n. are similar to those of the supraoptic n.; the axons of about 20% of their number join in the formation of the supraopticohypophysial tract and are functionally associated with the posterior lobe of the hypophysis; they project fibers to the brainstem nuclei (dorsal motor n. and solitary n.) and to the intermediolateral cell column of the spinal cord at thoracic, lumbar, and spinal levels; similar descending autonomic fibers arise from the lateral and posterior hypothalamic nuclei. SYN: filiform n., n. filiformis, n. paraventricularis hypothalami.
pedunculopontine tegmental n. [TA] See reticular nuclei of mesencephalon. SYN: n. tegmentalis pedunculopontinus [TA] .
n. pericuneatus lateralis [TA] SYN: lateral pericuneate n..
n. pericuneatus medialis [TA] SYN: medial pericuneate n..
perifornical n. [TA] See lateral hypothalamic area. SYN: n. perifornicalis [TA] .
n. perifornicalis [TA] SYN: perifornical n..
perihypoglossal nuclei [TA] nuclei found in the floor of the 4th ventricle in relation to the hypoglossal n.; term includes the prepositus and intercalated nuclei and the n. of Roller.
nuclei periolivares [TA] SYN: periolivary nuclei. See superior olivary n..
periolivary nuclei [TA] See superior olivary n.. SYN: nuclei periolivares [TA] .
peripeduncular n. [TA] a group of neuron cell bodies that form a thin, caplike configuration over the dorsolateral aspect of the crus cerebri; many of its cells are acetylcholinesterase-positive. SYN: n. peripeduncularis [TA] .
n. peripeduncularis [TA] SYN: peripeduncular n..
peritrigeminal n. [TA] small diffuse clusters of cells located mainly on the lateral aspect of the spinal tract of the trigeminal nerve, or insinuated within this fiber bundle at the level of and caudal to the obex. SYN: n. peritrigeminalis [TA] .
n. peritrigeminalis [TA] SYN: peritrigeminal n..
n. periventricularis posterior [TA] SYN: posterior periventricular n.. See intermediate hypothalamic area.
n. periventricularis ventralis [TA] SYN: anterior periventricular n.. See anterior hypothalamic area.
periventricular preoptic n. [TA] See anterior hypothalamic area. SYN: n. preopticus periventricularis [TA] .
nuclei of perizonal fields [TA] small groups of cells distributed along the course of, and insinuated within, pallidofugal fibers that form the lenticular fasciculus (n. of ventral field [TA], n. campi ventralis [TA], n. of field H2), that arch through the prerubral field (n. of medial field [TA], n. campi medialis [TA], n. of field H) and the thalamic fasciculus (n. of dorsal field [TA], n. campi dorsalis [TA], n. of field H1). SEE ALSO: fields of Forel, under field. SYN: nuclei camporum perizonalium [TA] .
Perlia n. a small cell group located between the somatic cell columns of the oculomotor nuclei. Because it is placed between the groups of motor neurons innervating, respectively, the left and right medial rectus muscles, the n. is considered to represent possibly an integrating mechanism for ocular convergence. SYN: convergence n. of Perlia, Spitzka n..
phenanthrene n. misnomer for tetracyclic steroid n..
phrenic n. n. of phrenic nerve.
n. of phrenic nerve [TA] neuron cell bodies located in the more medial portions of the anterior horn at cervical levels C3 to C7 that innervate the diaphragm via the phrenic nerve. SEE ALSO: phrenic n.. SYN: n. nervi phrenici [TA] , phrenic n.&star.
pontine nuclei [TA] the massive gray matter, composed of individual nuclei, that fills the basilar pons. These nuclei are of fairly homogenous architecture and project primarily to the contralateral side of the cerebellum by way of the middle cerebellar peduncle; there is a modest ipsilateral pontocerebellar projection. Their main afferents come from the entire extent of the cerebral neocortex by way of the corticopontine fibers (longitudinal pontine bundles); thus, the pontine nuclei form a major way-station in the impulse conduction from the cerebral cortex off one hemisphere to the posterior lobe off the opposite cerebellum. The pontine nuclei consist of: n. anterior [TA] (anterior n. [TA], ventral n. [TAalt]), n. lateralis [TA] (lateral n. [TA]), n. medianus [TA] (median n. [TA]), n. paramedianus [TA] (paramedian n. [TA]), n. peduncularis [TA] (peduncular n. [TA], peripeduncular n. [TAalt]), n. posterior lateralis [TA] (posterolateral n. [TA], dorsolateral n. [TAalt]), and n. posterior medialis [TA] (posteromedial n. [TA], dorsomedial n. [TAalt]). The n. reticularis tegmenti pontis [TA] (reticulotegmental n. [TA]) is located at the interface of tegmental and basilar portions of the pons and is sometimes grouped with the pontine nuclei. SYN: nuclei pontis [TA] , pontine gray matter.
nuclei pontis [TA] SYN: pontine nuclei.
pontobulbar n. [TA] an irregularly shaped layer of cells located dorsal and lateral to the restiform body at mid to rostral levels of the medulla oblongata; becomes larger immediately ventrolateral to the restiform body at the medulla-pons junction; these cells are similar to those of the basilar pontine nuclei. SYN: n. pontobulbaris [TA] .
n. pontobulbaris [TA] SYN: pontobulbar n..
n. posterior [TA] SYN: posterior n.. See accessory nuclei of optic tract.
posterior n. [TA] See accessory nuclei of optic tract. SYN: n. posterior [TA] .
posterior accessory olivary n. [TA] SYN: dorsal accessory olivary n..
n. of posterior commissure [TA] a group of cells located immediately adjacent to the posterior commissure at the mesencephalon-diencephalon junction; may be divided into pars ventralis [TA] (ventral subdivision [TA]), pars dorsalis [TA] (dorsal subdivision [TA]), and pars interstitialis [TA] (interstitial subdivision [TA]). SYN: n. commissurae posterioris [TA] .
n. posterior hypothalami [TA] SYN: posterior hypothalamic n..
posterior hypothalamic n. [TA] a large, periventricular hypothalamic n. located dorsal to the mamillary body, continuous with the central gray substance of the mesencephalon. SYN: n. posterior hypothalami [TA] .
n. posterior hypothalamic [TA] SYN: posterior n. of hypothalamus.
posterior n. of hypothalamus [TA] See posterior hypothalamic area. SYN: n. posterior hypothalamic [TA] .
posterior interpositus n. [TA] one of two cerebellar nuclei interposed between the fastigial and the dentate nuclei. SEE ALSO: globosus n.. SYN: n. interpositus posterior [TA] .
n. posterior nervi vagi [TA] SYN: posterior n. of vagus nerve.
posterior periventricular n. [TA] SYN: arcuate n. (1) . SYN: n. periventricularis posterior [TA] .
posterior thoracic n. [TA] a column of large neurons located in the base of the posterior gray column of the spinal cord, extending from the first thoracic through the second lumbar segment; it gives rise to the dorsal spinocerebellar tract of the same side. SYN: n. thoracicus posterior [TA] , dorsal thoracic n.&star, Clarke column, Clarke n., Stilling column, Stilling n..
posterior n. of vagus nerve the visceral motor n. located in the vagal trigone (ala cinerea) of the floor of the fourth ventricle. It gives rise to the parasympathetic fibers of the vagus nerve innervating the heart muscle and the smooth musculature and glands of the respiratory and intestinal tracts. SYN: n. posterior nervi vagi [TA] , n. dorsalis nervi vagi&star, dorsal motor n. of vagus, dorsal n. of vagus, dorsal vagal n., n. alae cinereae.
posterolateral n. [TA] See anterior horn.
n. posterolateralis [TA] See anterior horn.
posteromedial n. [TA] See anterior horn.
n. posteromedialis [TA] See anterior horn.
precommissural septal n. [TA] the vertically oriented layer of neuron cell bodies located rostral to the anterior commissure in the base of the septum pellucidum. SYN: n. septalis precommissuralis [TA] .
pregeniculate n. ventral lateral geniculate n..
n. premammillaris dorsalis [TA] SYN: dorsal premammillary n..
n. premammillaris ventralis [TA] SYN: ventral premammillary n..
n. preopticus lateralis [TA] SYN: lateral preoptic n..
n. preopticus medialis [TA] SYN: medial preoptic n..
n. preopticus medianus [TA] SYN: median preoptic n.. See anterior hypothalamic area.
n. preopticus periventricularis [TA] SYN: periventricular preoptic n.. See anterior hypothalamic area.
prerubral n. the gray matter of field H₂; See fields of Forel, under field.
pretectal nuclei [TA] group of cells, constituting several subnuclei, located rostral to the superior colliculus in the “pretectal” area; receive input from retinal ganglion cells (via the optic tract) and project bilaterally to the Edinger-Westphal n.; relay center for pupillary light reflex pathway; they consist of the n. pretectalis anterior [TA] (anterior pretectal n. [TA]), n. pretectalis olivaris [TA] (olivary pretectal n. [TA]), and n. pretectalis posterior [TA] (posterior pretectal n. [TA]). The n. tractus optici [TA] (n. of optic tract) is also usually grouped as one of the pretectal nuclei. SYN: nuclei pretectales [TA] .
nuclei pretectales [TA] SYN: pretectal nuclei.
n. principalis nervi trigemini [TA] SYN: principal sensory n. of trigeminal nerve.
principal olivary n. [TA] the largest part of the inferior olivary complex, consisting of an undulating layer of cells formed by a dorsal lamella [TA] (lamella posterior [TA]) and a ventral lamella [TA] (lamella anterior [TA]) connected with each other laterally by a lateral lamella [TA] (lamella lateralis [TA]). The medially directed opening of this continuous cell layer is the hilum. SYN: n. olivaris principalis [TA] .
principal sensory n. of trigeminal nerve [TA] the term commonly used to designate the n. pontis nervi trigeminalis; located in pons lateral to the motor trigeminal n.; receives primary sensory (touch and pressure) input via the trigeminal nerve and projects to ventral posteromedial n. of thalamus. SYN: n. principalis nervi trigemini [TA] , n. sensorius superior nervi trigemini, principal sensory n. of the trigeminus.
principal sensory n. of the trigeminus SYN: principal sensory n. of trigeminal nerve.
n. of pudendal nerve [TA] SYN: Onuf n..
n. pulposus [TA] the soft fibrocartilage central portion of the intervertebral disk; regarded as a derivative of the notochord. SYN: gelatinous n., n. gelatinosus, vertebral pulp.
pulvinar nuclei [TA] the large caudal portion of the lateral thalamic nuclear group; may be divided into four nuclei on the basis of cytoarchitecture and connections: n. pulvinaris anterior [TA] (anterior pulvinar n. [TA]), n. pulvinaris inferior [TA] (inferior pulvinar n. [TA]), n. pulvinaris lateralis [TA] (lateral pulvinar n. [TA]), and n. pulvinaris medialis [TA] (medial pulvinar n. [TA]); functionally related to the visual system. SYN: nuclei pulvinares [TA] .
nuclei pulvinares [TA] SYN: pulvinar nuclei.
n. pyramidalis obsolete term for n. olivaris accessorius medialis.
pyrrole n. of porphyrins, a cyclic tetrapyrrole; four pyrrole groups joined into a ring structure by way of –CH&dbond; (methylidyne) bridges between the α (2) position of one pyrrole and the α′ (5) position of another pyrrole, the fourth pyrrole being joined to the first. SEE ALSO: porphin, porphyrin.
raphe nuclei [TA] collective term denoting a variety of nerve cell groups in and along the median plane of the medulla oblongata [n. raphes obscurus [TA] (obscure raphe n. [TA]), n. raphes pallidus [TA] (pallidal raphe n. [TA]), and caudal portions of the n. raphes magnus [TA] (magnus raphe n. [TA])]; of the pons [rostral portions of the n. raphes magnus [TA] (magnus raphe n. [TA]), n. raphes pontis [TA] (pontine raphe n. [TA]), n. raphes medianus [TA] (median raphe n. [TA] or superior central n. [TAalt]), and caudal portions of the n. raphes posterior [TA] (posterior raphe n. [TA]) or dorsal raphe n. [TAalt])]; and of the mesencephalon [rostral portions of the n. raphe posterior [TA] (posterior raphe n. [TA]), n. linearis inferioris [TA] (inferior linear n. [TA]), n. linearis intermedius [TA] (intermediate linear n. [TA]), and n. linearis superior [TA] (superior linear n. [TA])]. These nuclei include neurons characterized by their containing the indolamine transmitter agent serotonin; their serotonin-carrying axons extend rostrally to the hypothalamus, septum, hippocampus, and cingulate gyrus and include projections to brainstem, cerebellum, and spinal cord. SYN: nuclei raphes [TA] .
nuclei raphes [TA] SYN: raphe nuclei.
red n. a large, well-defined, somewhat elongated cell mass, reddish-gray in the fresh brain, located in the rostral mesencephalic tegmentum. This n. is composed of a caudal pars magnocellularis [TA] (magnocellular part [TA]), a rostral pars parvocellularis [TA] (parvocellular part [TA]) and a small pars posteromedialis [TA] (posteromedial part [TA], dorsomedial part [TAalt]). The n. receives a massive projection from the contralateral half of the cerebellum by way of the superior cerebellar peduncle and an additional projection from the ipsilateral motor cortex. Projections from the anterior interposed n. and motor cortex to the red n. are somatopically organized. Its efferent connections are with the contralateral rhombencephalic reticular formation and spinal cord by way of the rubrobulbar and rubrospinal tracts. Rubrospinal fibers have somatotopic origin. SYN: n. ruber [TA] .
reduction n. a n. that degenerates in the cell during the changes incident to fertilization.
reproductive n. SYN: micronucleus (2) .
reticular nuclei of the brainstem the vaguely delineated cell groups composing the gray matter of the reticular formation of the medulla oblongata, pons, and mesencephalon. In general, large-celled territories occupy the medial two-thirds of the reticular formation: some examples are gigantocellular n. of medulla oblongata, nuclei tegmenti pontis caudalis and oralis. Smaller groups of reticular nuclei are found laterally and in paramedian locations; lateral nuclei receive sensory collaterals and project medially; paramedian reticular nuclei largely project to the cerebellum. SEE ALSO: reticular formation.
n. reticulares medullae oblongatae [TA] SYN: reticular nuclei of medulla oblongata.
nuclei reticulares mesencephali [TA] SYN: reticular nuclei of mesencephalon.
nuclei reticulares pontis [TA] SYN: reticular nuclei of pons.
n. reticularis pontis caudalis [TA] SYN: caudal pontine reticular n.. See reticular nuclei of pons.
n. reticularis pontis oralis [TA] SYN: oral pontine reticular n.. See reticular nuclei of pons.
n. reticularis tegmenti pontis [TA] See reticular nuclei of pons.
n. reticularis thalami [TA] SYN: reticular n. of thalamus.
reticular nuclei of medulla oblongata [TA] groups of neuron cell bodies located generally in the more central portions of each half of the medulla oblongata that are not all distinctly separated from each other yet may have specific connections. These nuclei are: gigantocellular reticular n. [TA] and its ventromedially located pars alpha [TA] (n. gigantocellularis [TA]), anterior gigantocellular reticular n. [TA] or ventral gigantocellular reticular n. [TAalt] (n. gigantocellularis anterior [TA]), lateral paragigantocellular reticular n. [TA] (n. paragigantocellularis lateralis [TA]), interfascicular n. of hypoglossal nerve [TA] (n. interfascicularis nervi hypoglossi [TA]), intermediate reticular n. [TA] (n. reticularis intermedius [TA]), parvocellular reticular n. [TA] (n. reticularis parvocellularis [TA]), posterior paragigantocellular reticular n. [TA] or dorsal paragigantocellular reticular n. [TAalt] (n. paragigantocellularis posterior [TA]) and medial reticular n. [TA] (n. reticularis medialis [TA]). The central reticular n. [TA] (n. reticularis centralis [TA]) can be divided into a dorsal part [TA] and a ventral part [TA] (pars dorsalis [TA], pars ventralis [TA]). The lateral reticular n. [TA] is located in the ventrolateral area of the medulla and can be divided into a magnocellular part [TA] (pars magnocellularis [TA]), a parvocellular part [TA] (pars parvocellularis [TA], and a subtrigeminal part [TA] (pars subtrigeminalis [TA]). SEE ALSO: reticular nuclei of the brainstem. SYN: n. reticulares medullae oblongatae [TA] .
reticular nuclei of mesencephalon [TA] diffusely arranged cell groups located in the dorsal and more medial area of the tegmentum of the mesencephalon. These nuclei are: cuneiform n. [TA] (n. cuneiformis [TA]), subcuneiform n. [TA] (n. subcuneiformis [TA]), parapeduncular n. [TA] (n. parapeduncularis [TA]), and the pedunculopontine tegmental n. [TA] (n. tegmentalis pedunculopontinus [TA]). This latter n. can be divided into a compact part [TA] or compact subnucleus [TAalt] (pars compacta [TA]) and a dissipated part [TA] or dissipated subnucleus [TAalt] (pars dissipata [TA]). SYN: nuclei reticulares mesencephali [TA] .
reticular nuclei of pons [TA] groups of cells located in the pontine tegmentum that are not clearly separate one from the other, but that have in some instances distinct connections. These nuclei are: caudal pontine reticular n. [TA] (n. reticularis pontis caudalis [TA]), oral pontine reticular n. [TA] (n. reticularis pontis oralis [TA]), paralemniscal n. [TA] (n. paralemniscalis [TA]), and the paramedian reticular n. [TA] (n. reticularis paramedianus [TA]). The reticulotegmental n. [TA] (n. reticularis tegmenti pontis [TA]) is located in the ventromedial portion of the pontine tegmentum and is correctly a part of the reticular complex of the pons; it is sometimes also associated with the dorsal extent of the basilar pontine nuclei. SYN: nuclei reticulares pontis [TA] .
reticular n. of thalamus [TA] a sheet of fairly large neurons covering the lateral, ventral, and rostral surfaces of the thalamus; its reticular appearance is caused by the numerous fascicles of the thalamic peduncles that traverse the n. The n. receives numerous fibers from the cerebral cortex, but it has no cortical projection. SYN: n. reticularis thalami [TA] .
retroposterior lateral n. See anterior horn.
n. reuniens [TA] a small cell group belonging to the midline group of thalamic nuclei and extending into the interthalamic adhesion (massa intermedia) when the latter is present.
rhombencephalic gustatory n. the rostral one-third of the n. of solitary tract, receiving afferents from the facial, glossopharyngeal, and vagus nerves conveying impulses originating from the receptor cells of the taste buds.
Roller n. 1. lateral n. of the accessory nerve; 2. a small bulbar n. lying immediately anterior to the hypoglossal n., considered one of the perihypoglossal nuclei. SEE subhypoglossal n..
roof n. SYN: fastigial n..
n. ruber [TA] SYN: red n..
n. saguli [TA] SYN: sagulum n..
sagulum n. [TA] a group of neuron cell bodies located between the lateral lemniscus and lateral surface of the brainstem immediately caudal to the inferior colliculus; functionally associated with the auditory system. SYN: n. saguli [TA] .
n. salivatorius inferior [TA] SYN: inferior salivatory n..
n. salivatorius superior [TA] SYN: superior salivatory n..
Schwalbe n. See vestibular nuclei.
secondary sensory nuclei SYN: terminal n..
segmentation n. 1. the compound n. in the impregnated ovum, formed by conjugation of the nuclei of the ovum and spermatozoon (female and male pronuclei); 2. the zygote n. after it commences the first cleavage division.
semilunar n. of Flechsig SYN: arcuate n. of thalamus.
n. sensorius superior nervi trigemini SYN: principal sensory n. of trigeminal nerve.
sensory nuclei a group of cell bodies that receive afferent (sensory) input from the periphery.
n. septalis precommissuralis [TA] SYN: precommissural septal n..
septofimbrial n. [TA] See septal area.
shadow n. a n. that has lost its pigment and staining properties.
sole nuclei an accumulation of skeletal muscle fiber nuclei at the myoneural junction.
nuclei of solitary tract a slender cell column extending sagittally through the dorsal part of the medulla oblongata, beneath the floor of the rhomboid fossa, immediately lateral to the limiting sulcus. This cell column is composed of smaller individual nuclei, and collectively they are the visceral sensory (visceral afferent) nuclei of the brainstem, receiving the afferent fibers of the vagus, glossopharyngeal, and facial nerves by way of the solitary tract. The caudal two-thirds of the n. processes impulses originating in the pharynx, larynx, intestinal and respiratory tracts, and heart and large blood vessels; its rostral one-third receives impulses from the taste buds and is known as the rhombencephalic gustatory n.. The individual nuclei that collectively make up what is commonly called the solitary n. are: parasolitary n. [TA] (n. parasolitarius [TA]), commissural n. [TA] (n. commissuralis [TA]), gelatinous solitary n. [TA] (n. gelatinosus solitarius [TA]), intermediate solitary n. [TA] (n. intermedius solitarius [TA]), interstitial solitary n. [TA] (n. interstitialis solitarius [TA]), medial solitary n. [TA] (n. medialis solitarius [TA]), paracommissural solitary n. [TA] (n. paracommissuralis solitarius [TA]), posterior solitary n. [TA] or dorsal solitary n. [TAalt] (n. solitarius posterior [TA]), posterolateral solitary n. [TA] or dorsolateral solitary n. [TAalt] (n. solitarius posterolateralis [TA]), anterior solitary n. [TA] or ventral solitary n. [TAalt] (n. solitarius anterior [TA]), and naterolateral solitary n. [TA] or ventrolateral solitary n. [TA] (n. solitarius anterolateralis [TA]). SYN: nuclei tractus solitarii [TA] .
somatic n. SYN: macronucleus (2) .
somatic motor nuclei collective term indicating the motor nuclei innervating the tongue musculature (hypoglossal n.) and the extraocular eye muscles (abducens nucleu, trochlear n., and oculomotor n.), the sternocleidomastoid and trapezius muscles (accessory nerve) and the skeletal muscles of the body (ventral roots of spinal nerves).
special visceral efferent nuclei SYN: branchiomotor nuclei.
special visceral motor nuclei SYN: branchiomotor nuclei.
sperm n. the n. in the head of the spermatozoon, which becomes the male pronucleus after entering the ovum. SEE ALSO: pronucleus.
spherical n. SYN: globosus n..
n. spinalis nervi trigemini [TA] SYN: spinal n. of trigeminal nerve.
spinal trigeminal n. See spinal n. of trigeminal nerve.
spinal n. of trigeminal nerve [TA] the long sensory n. extending from the caudal border of the pontine sensory n. of the trigeminus down through the lateral region of the rhombencephalon into the upper three segments of the spinal cord's dorsal horn; it receives the fibers of the sensory root of the trigeminal nerve that descend along its lateral border as the spinal tract of trigeminal nerve [TA]. This n. is divided into a pars caudalis [TA] (caudal part [TA]), a pars interpolaris [TA] (interpolar part [TA]), and a subnucleus oralis [TA] (oral subnucleus [TA]). The pars caudalis is further organized into a subnucleus zonalis [TA] (zonal subnucleus [TA]), a subnucleus gelatinosus [TA] (gelatinosus subnucleus [TA]), and a subnucleus magnocellularis [TA] (magnocellular subnucleus [TA]). SYN: n. spinalis nervi trigemini [TA] , descending n. of the trigeminus, spinal n. of the trigeminus.
spinal n. of the trigeminus SYN: spinal n. of trigeminal nerve.
Spitzka n. SYN: Perlia n..
Staderini n. SYN: intercalated n..
steroid n. SYN: tetracyclic steroid n..
Stilling n. SYN: posterior thoracic n..
subcaeruleus n. [TA] diffusely organized n. of noradrenergic cells located ventral to the n. caeruleus.
subcuneiform n. [TA] See reticular nuclei of mesencephalon. SYN: n. subcuneiformis [TA] .
n. subcuneiformis [TA] SYN: subcuneiform n.. See reticular nuclei of mesencephalon.
subhypoglossal n. [TA] a small bulbar n. lying immediately ventral (anterior) to the hypoglossal n.; considered one of the perihypoglossal nuclei. SYN: n. subhypoglossalis [TA] .
n. subhypoglossalis [TA] SYN: subhypoglossal n..
n. subparabrachialis [TA] SYN: subparabrachial n..
subparabrachial n. [TA] a cell group located ventral to the brachium conjunctivum in the general area where the medial and lateral parabrachial nuclei abut, shifting to the slightly more lateral position rostrally. SEE ALSO: parabrachial nuclei. SYN: n. subparabrachialis [TA] .
subthalamic n. [TA] a circumscript n., shaped like a biconvex lens, located in the ventral part of the subthalamus on the dorsal surface of the peduncular part of the internal capsule immediately rostral to the substantia nigra. The n. receives a massive topographic projection from the lateral segment of the globus pallidus and a somatopically organized projection from the ipsilateral motor cortex; a smaller bundle of afferents from the centromedian n. of the thalamus terminates in the rostral part of the n. The subthalamic n. projects to both pallidal segments, to the pars reticulata of the substantia nigra, and in a small way to the ipsilateral pedunculopontine n.. SYN: n. subthalamicus [TA] , corpus luysi, Luys body, n. of Luys.
n. subthalamicus [TA] SYN: subthalamic n..
superior central tegmental n. SYN: median raphe n.. See raphe nuclei.
superior olivary n. [TA] a circumscript cell group located ventrolaterally in the lower pontine tegmentum, immediately dorsal to the trapezoid body; the n. receives fibers from the ipsilateral and contralateral cochlear nuclei, and contributes fibers to the lateral lemniscus of each side. It is prominently involved in the function of spatial localization of sound. The n. (also called the superior olivary complex) consists of a lateral superior olivary n. [TA] (n. olivaris superior lateralis [TA]), medial superior olivary n. [TA] (n. olivaris superior medialis [TA]), and the periolivary nuclei [TA] (nuclei periolivares [TA]), which are usually divided into medial nuclei [TA] and lateral nuclei [TA] (nuclei mediales [TA] and nuclei laterales [TA]). SYN: n. olivaris superior [TA] , superior olivary complex&star.
superior salivary n. SYN: superior salivatory n..
superior salivatory n. [TA] a group of preganglionic parasympathetic motor neurons situated rostral and lateral to the inferior salivatory n.; it governs secretion of the lacrimal, sublingual, and submaxillary glands by way of the facial nerve and the sphenopalatine and submandibular ganglia. SYN: n. salivatorius superior [TA] , superior salivary n..
superior vestibular n. [TA] n. vestibularis superior. See vestibular nuclei. SYN: n. vestibularis superior [TA] .
suprachiasmatic n. [TA] See anterior hypothalamic area.
n. suprachiasmaticus [TA] small n. located dorsal to the optic chiasm; receives input from retina and influences hypothalamic neuroendocrine function; closely associated with regulation of circadian rhythmicity. SEE ALSO: anterior hypothalamic area.
supralemniscal n. [TA] a small group of neurons located dorsal to the medial lemniscus and insinuated among the fibers of the ventral trigeminothalamic tract at mid to rostral levels of the pons. SYN: n. supralemniscalis [TA] .
n. supralemniscalis [TA] SYN: supralemniscal n..
n. supramammillaris [TA] SYN: supramammillary n..
supramammillary n. [TA] See posterior hypothalamic area. SYN: n. supramammillaris [TA] .
supraoptic n. [TA] SYN: supraoptic n. [TA] of hypothalamus.
supraoptic n. [TA] of hypothalamus a large-celled neurosecretory n. in the hypothalamus, located over the lateral border of the optic tract, from which the supraopticohypophysial tract arises; its neurons produce and transport vasopressin released into the general circulation from the axon terminals in the supraopticohypophysial tract. This n. can be divided into a pars dorsolateralis [TA], pars dorsomedialis [TA], and pars ventromedialis [TA]. SYN: n. supraopticus [TA] , supraoptic n. [TA] .
n. supraopticus [TA] SYN: supraoptic n. [TA] of hypothalamus.
n. tecti SYN: fastigial n..
tegmental nuclei collective term for cell groups in the caudal midbrain and mid-to-rostral pons, one of which (ventral tegmental n.) is associated with the mammillary nuclei by way of the mammillary peduncle and mammillotegmental tract. Neurons in these nuclei are acetylcholinesterase-rich. The anterior tegmental n. [TA], also called the ventral tegmental n. [TAalt] (n. tegmentalis anterior [TA]), is located in the pontine tegmentum adjacent to the medial longitudinal fasciculus at the level of the trigeminal motor n.. The posterior tegmental n. [TA], also called the dorsal tegmental n. [TAalt], is located in the rostral pons in the area of the central gray substance. The lateroposterior tegmental n. [TA], also known as the laterodorsal tegmental n. [TAalt] (n. tegmentalis posterolateralis [TA]), is a larger cell group located partially in the central gray and partially ventrolateral to it at rostral pontine levels. The pedunculopontine tegmental n. [TA] (n. tegmentalis pedunculopontinus [TA]) is located in the rostral pons and caudal midbrain and consists of a compact part [TA] (pars compacta [TA] or compact subnucleus [TAalt]) and a dissipated part [TA] (pars dissipata [TA] or dissipated subnucleus [TAalt]. SYN: Gudden tegmental nuclei, nuclei tegmenti.
n. tegmentalis pedunculopontinus [TA] SYN: pedunculopontine tegmental n.. See reticular nuclei of mesencephalon.
nuclei tegmenti SYN: tegmental nuclei.
terminal n., n. terminalis collective term indicating those nerve cell groups in the rhombencephalon and spinal cord in which the afferent fibers of the spinal and cranial nerves terminate. SYN: n. terminationis [TA] , secondary sensory nuclei.
n. terminationis [TA] SYN: terminal n..
tetracyclic steroid n. the group of four fused rings forming the framework or parent substance of the steroids. SYN: perhydrocyclopenta[a]phenanthrene, steroid n..
thalamic gustatory n. SYN: arcuate n. of thalamus.
n. thoracicus posterior [TA] SYN: posterior thoracic n..
n. tractus olfactorii lateralis [TA] SYN: n. of the lateral olfactory tract.
nuclei tractus solitarii [TA] SYN: nuclei of solitary tract.
nuclei of trapezoid body [TA] small groups of neurons associated with the trapezoid body, forming the lateral n. of trapezoid body [TA] (n. lateralis corporis trapezoidei [TA]), medial n. of trapezoid body [TA] (n. medialis corporis trapezoidei [TA]), and the anterior n. of trapezoid body [TA] or ventral n. of trapezoid body [TA] (n. anterior corporis trapezoidei [TA]). These indistinct cell groups are involved in the relay of auditory input. SYN: nuclei corporis trapezoidei [TA] .
triangular n. alternative term for the medial vestibular n..
triangular n. of septum [TA] See septal area.
trochlear n. SYN: n. of trochlear nerve.
n. of trochlear nerve a group of motor neurons innervating the superior oblique muscle of the contralateral eye. The n. lies in the caudal half of the midbrain, behind the oculomotor n., in the most ventral part of the central gray substance, near the midline. SYN: n. nervi trochlearis [TA] , trochlear n..
trophic n. SYN: macronucleus (2) .
tuberal nuclei two or three small, encapsulated, round or ovoid clusters of cells in the lateral hypothalamic area along the surface of the tuber cinereum; their connections and functional significance are unknown. SYN: nuclei tuberales laterales [TA] .
nuclei tuberales laterales [TA] SYN: tuberal nuclei.
n. tuberomammillaris [TA] SYN: tuberomammillary n..
tuberomammillary n. [TA] See lateral hypothalamic area. SYN: n. tuberomammillaris [TA] .
ventral anterior n. [TA] of thalamus the most rostral of the subdivisions of the ventral n., receiving projections from the globus pallidus and projecting to the premotor and frontal cortex. This n. is divisible into a magnocellular division [TA] (pars magnocellularis [TA]) and a principal division [TA] (pars principalis [TA]). SYN: n. ventralis anterior [TA] .
nuclei ventrales thalami [TA] SYN: ventral nuclei of thalamus.
n. of ventral field [TA] See nuclei of perizonal fields. SYN: n. campi ventralis [TA] .
ventral intermediate n. [TA] of thalamus the composite middle third of the ventral n. receiving in its various parts distinctive projections from the contralateral half of the cerebellum (by way of the superior cerebellar peduncle) and the ipsilateral globus pallidus; nearly all parts of the n. project to the motor cortex. SYN: n. ventralis intermedius [TA] , n. ventralis lateralis, ventral lateral n. of thalamus.
n. ventralis [TA] SYN: ventral principal n.. See medial geniculate nuclei.
n. ventralis anterior [TA] SYN: ventral anterior n. [TA] of thalamus.
n. ventralis corporis geniculi lateralis [TA] SYN: ventral lateral geniculate n..
n. ventralis intermedius [TA] SYN: ventral intermediate n. [TA] of thalamus.
n. ventralis lateralis SYN: ventral intermediate n. [TA] of thalamus.
n. ventralis posterior intermedius thalami intermediate part of the ventrobasal nuclear complex. See ventral posterior n. of thalamus. SYN: ventral posterior intermediate n. of thalamus.
n. ventralis posterior thalami SYN: ventrobasal complex.
n. ventralis posterolateralis [TA] SYN: ventral posterolateral n. [TA] of thalamus.
n. ventralis posteromedialis [TA] SYN: ventral posteromedial n. [TA] of thalamus.
ventral lateral geniculate n. [TA] small cell group located rostral to the dorsal lateral geniculate n.. SYN: n. ventralis corporis geniculi lateralis [TA] , pregeniculate n.&star.
ventral lateral n. of thalamus SYN: ventral intermediate n. [TA] of thalamus.
ventral posterior intermediate n. of thalamus SYN: n. ventralis posterior intermedius thalami. See ventral posterior n. of thalamus.
ventral posterior n. of thalamus See ventrobasal complex.
ventral posterolateral n. [TA] of thalamus, ventral posterior lateral n. of thalamus lateral part of the ventrobasal nuclear complex. See ventrobasal complex. SYN: n. ventralis posterolateralis [TA] .
ventral posteromedial n. [TA] of thalamus, posterior medial n. of thalamus medial part of the ventrobasal nuclear complex. See ventrobasal complex. SYN: n. ventralis posteromedialis [TA] .
ventral premammillary n. [TA] See posterior hypothalamic area. SYN: n. premammillaris ventralis [TA] .
ventral principal n. [TA] See medial geniculate nuclei. SYN: n. ventralis [TA] .
ventral nuclei of thalamus [TA] a large, complex cell mass the external border of which forms the ventral and much of the lateral boundary, as well as the rostral border, of the thalamus; the nuclei making up this large area of the diencephalon are the ventral anterior n. [TA] (n. ventralis anterior [TA]), ventral lateral complex [TA] (nuclei ventrales laterales [TA]), ventral medial complex [TA] (nuclei ventrales medialis [TA]), ventral intermediate n. [TA] (n. ventralis intermedius [TA]), ventrobasal complex [TA] (nuclei ventrobasales [TA]), ventral posterior inferior n. [TA] (n. ventralis posterior internus [TA]), and ventral posterior parvocellular n. [TA] (n. ventroposterior parvocellularis [TA]). In general this area can be subdivided into an anterior, intermediate, and posterior part. SYN: nuclei ventrales thalami [TA] .
ventral tier thalamic nuclei collective term for nuclei in the ventral part of the lateral nuclear group, e.g., ventral anterior, lateral, posterolateral, and posteromedial nuclei and the medial geniculate nuclei and the dorsal lateral geniculate n.. The basoventral nuclear complex constitutes the caudal part of the ventral tier thalamic nuclei.
ventral n. of trapezoid body a cell group embedded among the fibers of the trapezoid body, the major decussation of the central auditory pathway, in the lower pons. The n. receives fibers from the contralateral cochlear nuclei and contributes fibers to the ascending auditory system or lateral lemniscus.
ventrobasal nuclei (complex) [TA] SYN: ventrobasal complex.
nuclei ventrobasales [TA] SYN: ventrobasal complex.
ventrolateral n. [TA] See anterior horn.
ventromedial n. [TA] See intermediate hypothalamic area.
ventromedial n. of hypothalamus [TA] a circumscript ovoid group of small neurons in the medial zone of the tuberal region of the hypothalamus. Bilateral destruction of this n. in the rat leads to severe obesity. It receives numerous fibers from the amygdala via the terminal stria; its efferent connections are obscure. SYN: n. ventromedialis hypothalami [TA] .
n. ventromedialis hypothalami [TA] SYN: ventromedial n. of hypothalamus. See intermediate hypothalamic area.
vestibular nuclei [TA] a group of four main nuclei that are located in the lateral region of the hindbrain beneath the floor of the rhomboid fossa. These nuclei are the inferior vestibular n., medial vestibular n. (Schwalbe n.), lateral vestibular n. (Deiter n.), and superior vestibular n. (Bechterew n.). The inferior n. contains a group of large cells, the magnocellular part of inferior vestibular n. [TA] or cell group F [TAalt] (pars magnocellularis nuclei vestibularis inferioris [TA]), located caudally in the n.. A group of medium-sized neurons is located in lateral portions of the lateral n., the parvocellular part [TA] or cell group I [TAalt] (pars parvocellularis [TA]). These nuclei receive primary fibers of the vestibular nerve, are reciprocally connected with the flocculonodular lobe of the cerebellum, and project by way of the medial longitudinal fasciculus to the abducens, trochlear, and oculomotor nuclei and to the ventral horn of the spinal cord. The lateral vestibular n. projects to the ipsilateral ventral horn of the spinal cord by the vestibulospinal tract. SYN: nuclei vestibulares [TA] .
nuclei vestibulares [TA] SYN: vestibular nuclei.
n. vestibularis inferior [TA] SYN: inferior vestibular n.. See vestibular nuclei.
n. vestibularis lateralis [TA] SYN: lateral vestibular n.. See vestibular nuclei.
n. vestibularis medialis [TA] SYN: medial vestibular n.. See vestibular nuclei.
n. vestibularis superior [TA] SYN: superior vestibular n.. See vestibular nuclei.
vestibulocochlear nuclei the combined cochlear and vestibular nuclei in the brainstem that receive the incoming fibers of the eighth cranial nerve. See vestibular nuclei. SYN: nuclei nervi vestibulocochlearis.
nuclei viscerales nervi oculomotorii the visceral motor n. of the oculomotor nerve, also commonly called the Edinger-Westphal n., can be divided into an anterior medial n. [TA] (n. anteromedialis [TA]), and a posterior n. [TA] (n. dorsalis [TA]) SEE ALSO: Edinger-Westphal n..
visceral nuclei of oculomotor nerve [TA] SYN: Edinger-Westphal n..

nuclide
nuclide (noo′klid)

A particular (atomic) nuclear species with defined atomic mass and number. SEE ALSO: isotope.

Nuel
Nuel

Jean Pierre, Belgian ophthalmologist and otologist, 1847–1920. See N. space.

NUG
NUG

Abbreviation for necrotizing ulcerative gingivitis.

Nuhn
Nuhn

Anton, German anatomist, 1814–1889. See N. gland.

nulligravida
nulligravida (nul-i-grav′i-da)

A woman who has never conceived a child. [L. nullus, none, + gravida, pregnant]

nullipara
nullipara (nu-lip′a-ra)

A woman who has never borne a child. [L. nullus, none, + pario, to bear]

nulliparity
nulliparity (nul-i-par′i-te)

Condition of having borne no children.

nulliparous
nulliparous (nul-ip′a-rus)

Never having borne a child. SYN: nonparous.

number
number (num′ber)

1. A symbol expressive of a certain value or of a specific quantity determined by count. 2. The place of any unit in a series.
atomic n. (Z) the n. of protons in the nucleus of an atom; it indicates the position of the element in the periodic system.
Avogadro n. (Λ, N_A) the n. of molecules in 1 gram-molecular weight (1 mol) of any compound; defined as the n. of atoms in 0.0120 kg of pure carbon-12; equivalent to 6.0221367 × 10²³. SYN: Avogadro constant.
Brinell hardness n. (BHN) a n. related to the size of the permanent impression made by a ball indenter of specified size (usually 10 mm in diameter) pressed into the surface of the material under a specified load: where P = applied load in kg, D = diameter of the ball in mm, and d = diameter of the impression in mm.
CT n. a normalized value of the calculated x-ray absorption coefficient of a pixel (picture element) in a computed tomogram, expressed in Hounsfield units, where the CT n. of air is −1000 and that of water is 0. SYN: Hounsfield n..
electronic n. the n. of electrons in the outermost orbit (valence shell) of an element.
gold n. SYN: gold equivalent.
Hehner n. the weight or percentage of the nonvolatile fatty acids yielded by 5 g of a saponified fat or oil. SYN: Hehner value.
Hogben n. unique personal identifying n. constructed by using a sequence of digits for birth date, sex, birthplace, and other identifiers; invented by and named for Lancelot Hogben, British mathematician; Hogben numbers are the basis for identification numbers in many primary care facilities and are used in many record linkage systems.
Hounsfield n. SYN: CT n..
hydrogen n. the quantity of hydrogen that 1 g of fat will absorb; it is a measurement of the amount of unsaturated fatty acids in the fat. SEE ALSO: iodine n..
iodine n. an indication of the quantity of unsaturated fatty acids present in a fat; it represents the n. of grams of iodine absorbed by each 100 g of fat. SEE ALSO: hydrogen n.. SYN: iodine value.
Kestenbaum n. the difference between the two pupil diameters when each eye is measured in bright light with the other eye tightly covered; an indicator of the relative afferent pupillary defect in patients with two normally innervated irises.
Knoop hardness n. (KHN) a n. obtained by dividing the load in kg applied to a pyramid-shaped diamond of specific size divided by the projected area of the impression: KHN = L/A, where A= the projected area of the impression in mm² and L = the load in kg; used for measurements of hardness of any materials, especially very hard and brittle substances such as tooth dentin and enamel.
Koettstorfer n. SYN: saponification n..
linking n. (L) a property of a long biopolymer (such as duplex DNA) equal to the n. of twists (related to the frequency of turns around the central axis of the helix) plus the writhing n..
Loschmidt n. (n₀) the n. of molecules in 1 cm³ of ideal gas at 0°C and 1 atm of pressure; Avogadro n. divided by 22,414 ( i.e., 2.6868 × 10¹⁹ cm⁻³).
Mach n. a n. representing the ratio between the speed of an object moving through a fluid medium, such as air, and the speed of sound in the same medium.
mass n. the mass of the atom of a particular isotope relative to hydrogen-1 (or to 112 the mass of carbon-12), generally very close to the whole n. represented by the sum of the protons and neutrons in the atomic nucleus of the isotope (indicated in the name or symbol of the isotope; e.g., oxygen-16, ¹⁶O); not to be confused with the atomic weight of an element, which may include a n. of isotopes in natural proportion.
MIM n. the catalog assignment for a mendelian trait in the MIM system. If the initial digit is 1, the trait is deemed autosomal dominant; if 2, autosomal recessive; if 3, X-linked. Wherever a trait defined in this dictionary has a MIM n., the n. from the 12th edition of MIM, is given in square brackets with or without an asterisk (asterisks indicate that the mode of inheritance is known; a n. symbol (#) before an entry n. means that the phenotype can be caused by mutation in any of 2 or more genes) as appropriate e.g., Pelizaeus-Merzbacher disease [MIM*169500] is a well-established, autosomal, dominant, mendelian disorder.
Polenské n. the n. of milliliters of 0.1 n KOH required to neutralize the nonvolatile fatty acids obtained from 5 g of a saponified fat or oil.
Reichert-Meissl n. an index of the volatile acid content of a fat; the n. of milliliters of 0.1 n KOH required to neutralize the soluble volatile fatty acids in 5 g of fat that has been saponified, acidified to liberate the fatty acids, and then steam-distilled. SYN: volatile fatty acid n..
Reynolds n. a dimensionless n. that describes the tendency for a flowing fluid, such as blood, to change from laminar flow to turbulent flow or vice versa.
saponification n. the n. of milligrams of KOH required to saponify 1 g of fat; an approximate measure of the average molecular weight of a fat, with which it varies inversely. SYN: Koettstorfer n..
stoichiometric n. (ν) the n. associated with a reactant or product participating in a defined chemical reaction; usually an integer.
thiocyanogen n. the n. of grams of thiocyanogen taken up by 100 g of fat; analogous to the iodine n., except that thiocyanogen will not add to all the double bonds in polyunsaturated fatty acids, as will iodine. SYN: thiocyanogen value.
transport n. the fraction of the total current carried through a solution by a particular type of ion present in that solution.
turnover n. (k_cat) the n. of substrate molecules converted into product in an enzyme-catalyzed reaction under saturating conditions per unit time per unit quantity of enzyme; e.g., k_cat = V_max/[E_total].
volatile fatty acid n. SYN: Reichert-Meissl n..
wave n. the n. of waves (of any waveform such as light or sound) per unit length.
writhing n. the n. of times a DNA duplex axis crosses over itself in space.

numbness
numbness (num′nes)

Indefinite term for abnormal sensation, including absent or reduced sensory perception as well as paresthesias.

nummiform
nummiform (num′i-form)

SYN: nummular.

nummular
nummular (num′u-ler)

1. Discoid or coin-shaped; denoting the thick mucous or mucopurulent sputum in certain respiratory diseases, so called because of the disc shape assumed when it is flattened on the bottom of a sputum mug containing water or transparent disinfectant. 2. Arranged like stacks of coins, denoting the lining up of the red blood cells into rouleaux formation. SYN: nummiform. [ L. nummulus, small coin, dim. of nummus, coin]

nummulation
nummulation (num-u-la′shun)

Formation of nummular masses.

nunnation
nunnation (nu-na′shun)

A speech disorder in which the n sound is given to other consonants. [Ar. nun, the letter n.]

nurse
nurse (ners)

1. To breast feed. 2. To provide care of the sick. 3. One who is educated in the scientific basis of nursing under defined standards of education and is concerned with the diagnosis and treatment of human responses to actual or potential health problems. [O. Fr. nourice, fr. L. nutrix, wet-n., n., fr. nutrio, to sucke, to tend]
certified registered n. anesthetist (C.R.N.A.) a registered professional n. with additional education in the administration of anesthetics. Certification achieved through a program of study recognized by the American Association of N. Anesthetists.
charge n. a n. administratively responsible for a designated hospital unit, usually on an 8-hour basis. SYN: head n. (2) .
clinical n. specialist a registered n. with at least a master's degree who has advanced education in a particular area of clinical practice such as oncology or psychiatry. Usually employed in a hands-on clinical setting such as a hospital.
community n. SYN: public health n..
community health n. SYN: public health n..
dry n. a woman who cares for newborn infants without breast feeding them, as opposed to a wet n..
n. epidemiologist a registered n. with additional education in the monitoring and prevention of nosocomial infections in the client population in an agency. SYN: infection control n..
flight n. a n. who cares for clients during transport in any type of aircraft.
general duty n. n. who accepts assignment to any unit of a hospital other than an intensive care unit.
graduate n. a n. who has received a degree, most often a bachelor's degree, from a school or college of nursing.
head n. 1. a n. administratively responsible for a designated hospital unit on a 24 hour basis; 2. SYN: charge n..
home health n. a n. who is responsible for a group of clients in the home setting. Visits clients on a routine basis to assist client and family with care as needed and to teach family the care needed so that the client may remain in his/her home. SYN: visiting n..
hospital n. a registered n. working in a hospital.
infection control n. SYN: n. epidemiologist.
licensed practical n. (L.P.N.) a n. who has graduated from an accredited school of practical (vocational) nursing, passed the state examination for licensure, and been licensed to practice by a state authority. Program is generally 1 year in length. SYN: licensed vocational n..
licensed vocational n. (L.V.N.) SYN: licensed practical n..
practical n. a graduate of a specific educational program that prepares the individual for a career in nursing with less responsibility than a graduate or registered n..
private n. SYN: private duty n..
private duty n. 1. a n. who is not a member of a hospital staff, but is hired by the client or his/her family on a fee-for-service basis to care for the client; 2. a n. who specializes in the care of patients with diseases of a particular class, e.g., surgical cases, tuberculosis, children's diseases. SYN: private n..
public health n. a n. who provides care to individuals or groups in a community outside of institutions. Usually works through the auspices of a state or city health department. SYN: community health n., community n..
registered n. (R.N.) a n. who has graduated from an accredited nursing program, has passed the state examination for licensure, and has been registered and licensed to practice by a state authority.
school n. a n., usually an RN, working in a school or similar institution.
scrub n. a n. who has scrubbed arms and hands, donned sterile gloves and, usually, a sterile gown, and assists an operating surgeon, primarily by passing instruments.
special n. a n., who might be a registered n. or a practical n., assigned to limited, specialized functions; usually synonymous with private duty n..
student n. a student in a program leading to certification in a form of nursing; usually applied to students in an RN or practical n. program.
visiting n. SYN: home health n..
wet n. a woman who breast feeds a child not her own.

nurse practitioner nurse practitioner (ners prak-tish′u-ner)

A registered nurse with at least a master's degree in nursing and advanced education in the primary care of particular groups of clients; capable of independent practice in a variety of settings.Nurse practitioners have been recognized in the U.S. since 1955. State laws regulate their scope of practice and degree of autonomy. By assuming responsibility for preventive care, health education, routine surveillance, and the management of chronic disorders, nurse practitioners free physicians to render more sophisticated or elaborate diagnostic and therapeutic services. In thinly populated areas they enable patients to receive treatment for most medical problems without having to travel long distances. Some observers have noted that the pursuit by nurse practitioners of increasing autonomy and their popularity with managed care organizations threaten to diminish the quality of primary medical care.

nursing
nursing (ner′sing)

1. Feeding an infant at the breast; tending and caring for a child. 2. The scientific application of principles of care related to prevention of illness and care during illness.
n. assignment the method(s) by which the patient care load is distributed among the n. personnel available to provide care.
n. audit a defined procedure used to evaluate the quality of n. care provided within an agency to its clients.
n. model a set of abstract and general statements about the concepts that serve to provide a framework for organizing ideas about clients, their environment, health, and n..
n. plan of care the written framework that provides direction for the delivery of n. care.
n. process a five-part systematic decision-making method focusing on identifying and treating responses of individuals or groups to actual or potential alterations in health. Includes assessment, n. diagnosis, planning, implementation, and evaluation. The first phase of the n. process is assessment, which consists of data collection by such means as interviewing, physical examination, and observation. It requires collection of both objective and subjective data. The second phase is n. diagnosis, a clinical judgment about individual, family or community n. responses to actual or potential health problems/life processes. Provides the basis for selection of n. intervention to achieve outcomes for which the nurse is accountable (NANDA, 1990). The third phase is planning, which requires establishment of outcome criteria for the client's care. The fourth phase is implementation (intervention). This phase involves demonstrating those activities that will be provided to and with the client to allow achievement of the expected outcomes of care. Evaluation is the fifth and final phase of the n. process. It requires comparison of client's current state with the stated expected outcomes and results in revision of the plan of care to enhance progress toward the stated outcomes.

nursing home
nursing home

A convalescent home or private facility for the care of individuals who do not require hospitalization and who cannot be cared for at home.

Nussbaum
Nussbaum

Johann H.R. von, German surgeon, 1829–1890.

nutation
nutation (noo-ta′shun)

The act of nodding, especially involuntary nodding. [L. annuo, to nod]

nutgall
nutgall (nut′gahl)

An excrescence on the oak, Quercus infectoria (family Fagaceae) and other species of Quercus, caused by the deposit of the ova of a fly, Cynips gallae tinctorae; an astringent and styptic, by virtue of the tannin it contains. SYN: gall (3) , galla, oak apple.

nutmeg
nutmeg (nut′meg)

The dried ripe seed of Myristica fragrans (family Myristicaceae), deprived of its seed coat and arillode; an aromatic stimulant, carminative, condiment, and source of volatile and expressed n. oils; it is consumed for its bizarre central nervous system effects. SEE ALSO: myristicin. SYN: myristica.

nutmeg oil
nutmeg oil

The volatile oil distilled from the dried kernels of the ripe seeds of Myristica fragrans; used as a flavoring agent and a carminative; in large quantities, it may produce narcosis and delirium; the fixed oil expressed from M. fragrans is used as a rubefacient. SYN: myristica oil.

nutrient
nutrient (noo′tre-ent)

A constituent of food necessary for normal physiologic function. [L. nutriens, fr. nutrio, to nourish]
essential nutrients nutritional substances required for optimal health. These must be in the diet, because they are not formed metabolically within the body.
trace n. SYN: micronutrients.

nutrilites
nutrilites (noo′tri-lits)

Essential nutritional factors. [L. nutrio, to suckle, nourish]

nutrition
nutrition (noo-trish′un)

1. A function of living plants and animals, consisting in the taking in and metabolism of food material whereby tissue is built up and energy liberated. SYN: trophism (2) . 2. The study of the food and liquid requirements of human beings or animals for normal physiologic function, including energy, need, maintenance, growth, activity, reproduction, and lactation. [L. nutritio, fr. nutrio, to nourish]
total parenteral n. (TPN) n. maintained entirely by central intravenous injection or other nongastrointestinal route.

nutritive
nutritive (noo′tri-tiv)

1. Pertaining to nutrition. 2. Capable of nourishing. SYN: alible.

nutriture
nutriture (noo′tri-choor)

State or condition of the nutrition of the body; state of the body with regard to nourishment. [L. nutritura, a nursing, fr. nutrio, to nourish]

Nuttall
Nuttall

G. H. F., U.S. biologist, 1862–1937. See Nuttallia.

Nuttallia
Nuttallia (nu-tal′e-a)

Former name for Babesia.

nux vomica
nux vomica (nuks vom′i-ka)

Poison nut or Quaker button, the seed of Strychnos nux-vomica (family Logeniaceae), a tree of tropical Asia; it contains two alkaloids, strychnine and brucine; it has been used as a bitter tonic and central nervous system stimulant. [Mod. L. emetic nut, fr. L. nux, nut, + vomo, to vomit]

Nva
Nva

Abbreviation for norvaline.

nyct- nyct-

See nycto-.

nyctalgia
nyctalgia (nik-tal′je-a)

Denoting especially the osteocopic pains of syphilis occurring at night. SYN: night pain. [nyct- + G. algos, pain]

nyctalopia
nyctalopia (nik-ta-lo′pe-a)

Decreased ability to see in reduced illumination. Seen in patients with impaired rod function; often associated with a deficiency of vitamin A. SYN: day sight, night blindness, nocturnal amblyopia, nyctanopia. [nyct- + G. alaos, obscure, + ops, eye]
n. with congenital myopia [MIM*310500] an abnormality of X-linked inheritance characterized by low visual acuity, strabismus, or nystagmus.

nyctanopia
nyctanopia (nik-ta-no′pe-a)

SYN: nyctalopia. [nyct- + G. an- priv. + opsis, sight]

nycterine
nycterine (nik′ter-in, -in)

1. By night. 2. Dark or obscure. [G. nykterinos]

nycterohemeral
nycterohemeral (nik′ter-o-he′mer-al)

SYN: nyctohemeral. [G. nykteros, by night, nightly, + hemera, day]

nycto- nycto-, nyct-

Night, nocturnal. SEE ALSO: noct-. [G. nyx]

nyctohemeral
nyctohemeral (nik-to-he′mer-al)

Both daily and nightly. SYN: nycterohemeral. [nycto- + G. hemera, day]

nyctophilia
nyctophilia (nik-to-fil′e-a)

Preference for the night or darkness. SYN: scotophilia. [nycto- + G. philos, fond]

nyctophobia
nyctophobia (nik-to-fo′be-a)

Morbid fear of night or of the dark. SYN: scotophobia. [nycto- + G. phobos, fear]

Nyctotherus
Nyctotherus (nik-to-the′rus)

A genus of Ciliophora, one species of which, N. faba, has been reported, though rarely, from the human intestine; it is generally found in amphibia. [G. nyktotheras, one who hunts by night, fr. therao, to hunt, fr. ther, wild beast]

nycturia
nycturia (nik-too′re-a)

SYN: nocturia.

Nyhan
Nyhan

William L. U.S. pediatrician, *1926. See Lesch-N. syndrome.

nylidrin hydrochloride
nylidrin hydrochloride (ni′li-drin, nil′)

A sympathomimetic agent, similar to isoproterenol, that produces vasodilation of arterioles of skeletal muscles and increases muscle blood flow; used in the treatment of peripheral vascular diseases.

nymph
nymph (nimf)

1. The earliest series of stages in metamorphosis following hatching in the development of hemimetabolous insects ( e.g., locusts); the n. resembles the adult in many respects, but lacks full wing or genitalia development; it grows through successive instars without any intermediate or pupal stage into the imago or adult form. SEE ALSO: incomplete metamorphosis, complete metamorphosis. 2. The third stage in the life cycle of a tick, between the larva and the adult. [G. nymphe, maiden]

nympha
nympha, pl .nymphae (nim′fa, nim′fe)

One of the labia minora. [Mod. L., fr. G. nymphe, a bride]

nymphal
nymphal (nim′fal)

1. Pertaining to a nymph. 2. Pertaining to the labia minora (nymphae).

nymphectomy
nymphectomy (nim-fek′to-me)

Surgical removal of hypertrophied labia minora. [nympha + G. ektome, excision]

nymphitis
nymphitis (nim-fi′tis)

Inflammation of the labia minora. [nympha + G. -itis, inflammation]

nympho- nympho-, nymph-

The nymphae (labia minora). [L. nympha]

nympholabial
nympholabial (nim′fo-la′be-al)

Relating to the labia minora (nymphae) and the labia majora; denoting a furrow between the two labia on each side.

nympholepsy
nympholepsy (nim-fo-lep′se)

Demoniac frenzy, especially of an erotic nature. [nympho- + G. lepsis, a seizure]

nymphomania
nymphomania (nim-fo-ma′ne-a)

An insatiable impulse to engage in sexual behavior in a female; the counterpart of satyriasis in a male. [nympho- + G. mania, frenzy]

nymphomaniac
nymphomaniac (nim-fo-ma′ne-ak)

A female exhibiting nymphomania.

nymphomaniacal
nymphomaniacal (nim′fo-ma-ni′a-kal)

Pertaining to, or exhibiting, nymphomania.

nymphoncus
nymphoncus (nim-fong′kus)

Swelling or hypertrophy of one or both labia minora. [nympho- + G. onkos, tumor]

nymphotomy
nymphotomy (nim-fot′o-me)

Incision into the labia minora or the clitoris. [nympho- + G. tome, incision]

nystagmic
nystagmic (nis-tag′mik)

Relating to or suffering from nystagmus.

nystagmiform
nystagmiform (nis-tag′mi-form)

SYN: nystagmoid.

nystagmogram
nystagmogram (nis-tag′mo-gram)

The tracing produced by a nystagmograph.

nystagmograph
nystagmograph (nis-tag′mo-graf)

An apparatus for measuring the amplitude, periodicity, and velocity of ocular movements in nystagmus, by measuring the change in the resting potential of the eye as the eye moves. [nystagmus + G. grapho, to write]

nystagmography
nystagmography (nis-tag-mog′ra-fe)

The technique of recording nystagmus.

nystagmoid
nystagmoid (nis-tag′moyd)

Resembling nystagmus. SYN: nystagmiform. [nystagmus + G. eidos, resemblance]

nystagmus
nystagmus (nis-tag′mus)

Involuntary rhythmic oscillation of the eyeballs, either pendular or with a slow and fast component. [G. nystagmos, a nodding, fr. nystazo, to be sleepy, nod]
after-n. n. occurring after the abrupt cessation of rotation in the opposite direction of the rotatory n..
amaurotic n. SYN: ocular n..
Bruns n. a fine, jerking (vestibular) n. on horizontal gaze in one direction, together with a slower, larger amplitude (gaze, paretic) n. on looking in the opposite direction; due to lateral brainstem compression, usually by a cerebellar-pontine angle mass such as an acoustic neuroma.
caloric n. n. with slow and fast components induced by labyrinthine stimulation with warm or cool water in the ear. SEE ALSO: Bárány sign.
cervical n. n. arising from a lesion of the proprioceptive mechanism of the neck.
compressive n. a jerky n. resulting from unilateral changes of pressure in semicircular canals.
congenital n. 1. n. present at birth or caused by lesions sustained in utero or at the time of birth; 2. inherited n., usually X-linked, without associated neurologic lesions and nonprogressive; all three patterns of mendelian inheritance may occur: autosomal dominant [MIM*164100, *164150], autosomal recessive [MIM*257400], or X-linked recessive [MIM*310800, *310700]; 3. the n. associated with albinism, achromatopsia, and hypoplasia of the macula.
conjugate n. a n. in which the two eyes move simultaneously in the same direction.
convergence-retraction n. irregular, jerky n. combining convergence and retraction of the eye into the orbit, especially on attempting an upward gaze. SYN: Koerber-Salus-Elschnig syndrome.
deviational n. SYN: end-point n..
dissociated n. a n. in which the movements of the two eyes are dissimilar in direction, amplitude, and periodicity. SYN: dysjunctive n., incongruent n., irregular n..
downbeat n. a vertical n. with a rapid component downward, occurring in lesions of the lower part of the brainstem or cerebellum.
dysjunctive n. SYN: dissociated n..
end-point n. a jerky, physiologic n. occurring in a normal individual when attempts are made to fixate a point at the limits of the field of fixation. SYN: deviational n..
fast component of n. compensatory movement of the eyes in the vestibuloocular reflex.
fixation n. n. aggravated or induced by ocular fixation, arising as optokinetic n., or resulting from midbrain lesions.
galvanic n. n. involving galvanic stimulation of the labyrinth.
gaze paretic n. a n. occurring in partial gaze paralysis when an attempt is made to look in the direction of the gaze paresis.
incongruent n. SYN: dissociated n..
irregular n. SYN: dissociated n..
jerky n. n. in which there is a slow drift of the eyes in one direction, followed by a rapid recovery movement, always described in the direction of the recovery movement; it usually arises from labyrinthine or neurologic lesions or stimuli.
labyrinthine n. SYN: vestibular n..
latent n. jerky n. that is brought out by covering one eye. The fast phase is always away from the covered eye.
miner's n. n. occurring in 19th century coal miners and thought at the time to be related to lack of illumination as well as other factors. SYN: miner's disease (1) .
minimal amplitude n. SYN: micronystagmus.
ocular n. the pendular or, rarely, jerky n. seen in severely reduced vision. SYN: amaurotic n..
opticokinetic n. SYN: optokinetic n..
optokinetic n. n. induced by looking at moving visual stimuli. SYN: opticokinetic n., railroad n..
palatal n. a clonic spasm of the levator palati muscle, causing an audible click. SEE ALSO: palatal myoclonus.
pendular n. a n. that, in most positions of gaze, has oscillations equal in speed and amplitude, usually arising from a visual disturbance.
positional n. n. occurring only when the head is in a particular position.
railroad n. SYN: optokinetic n..
rotational n. jerky n. arising from stimulation of the labyrinth by rotation of the head around any axis and induced by change of motion.
rotatory n. a movement of the eyes around the visual axis.
seesaw n. a n. in which one eye moves upward as the other moves downward, often combined with a torsional rotation (down and out, up and in—as in a see-saw).
slow component of n. the fundamental movement of the eyes in the vestibuloocular reflex.
upbeat n. a vertical jerky n. with a rapid component upward, occurring with brainstem lesions.
vertical n. an up-and-down oscillation of the eyes.
vestibular n. n. resulting from physiological stimuli to the labyrinth that may be rotatory, linear, caloric, compressive, or galvanic, or due to labyrinthal lesions. SEE ALSO: Bárány sign. SYN: labyrinthine n..
voluntary n. pendular n. in which the individual causes an extremely fine and rapid horizontal oscillation of the eyes. The nystagamus consists of back-to-back saccades and is seldom done for more than a few seconds at a time.

nystatin
nystatin (ni-stat′in, nis′ta-tin)

An antibiotic substance isolated from cultures of Streptomyces noursei, effective in the treatment of all forms of candidiasis, particularly candidal infections of the intestine, skin, and mucous membranes. SYN: fungicidin. [New York State + -in]

Nysten
Nysten

Pierre H., French physician, 1771–1818. See N. law.

nyxis
nyxis (nik′sis)

A pricking; paracentesis. [G.]

Nω-phosphonocreatine
N^ω-phosphonocreatine

SYN: phosphocreatine.

N-succinyladenylic acid
N-succinyladenylic acid (suk-sin-il-ad-e-nil′ik)

SYN: adenylosuccinic acid.

N-sulfanilylacetamide
N-sulfanilylacetamide (sul-fan′i-lil-a-set′a-mid)

SYN: sulfacetamide.

N-sulfanilylbenzamide
N-sulfanilylbenzamide (sul-fan′i-lil-ben′za-mid)

SYN: sulfabenzamide.

n-tetracosanoic acid
n-tetracosanoic acid (tet′ra-ko-sa-no′ik)

SYN: lignoceric acid.

Nε-trimethyllysine
N^ε-trimethyllysine (tri-meth-il-li-sen)

An amino acid residue found in a number of proteins by the action of S-adenosyl-l-methionine on l-lysyl residues; upon release by proteolysis, N^ε-trimethyllysine becomes the precursor of carnitine.