| ANN | artificial neural network |
|---|---|
| NCAM | neural cell adhesion molecule |
| NL | neural lobe; neutral lipid; nodular lymphoma; normal; normal libido, normal limits |
| NR | do not repeat [Lat. non repetatur]; nerve root; neural retina; neutral red; noise reduction; nonreac... |
| NTD | neural tube defect; nitroblue tetrazolium dye; noise tone difference; 5'-nucleotidase |
| neural tube | <embryology> The progenitor of the central nervous system. See: neural plate, neurulation. (18 Nov 1997) |
|---|---|
| neural tube defect | <neurology, paediatrics> Abnormal development during embryonic life of the neural tube producing congenital malformations of the nervous system due to closure failure of the neural tube. The structure gives rise to the central nervous system (the brain and spinal cord), and failure to close results in anencephaly (absence of the cranial vault and absence of most or all of the cerebral hemispheres of the brain) and spina bifida or meningomyelocele (open spina with exposure and protusion of the spinal cord). The risk of neuroal tube defects can be decreased by the mother taking folic acid during pregnancy. (04 Jul 1999) |
| dorsal plate of neural tube | The thin layer of the embryonic neural tube connecting the alar plate's dorsally. Synonym: dorsal plate of neural tube. (05 Mar 2000) |
| dorsolateral plate of neural tube | The dorsal division of the lateral walls of the neural tube in the embryo; it gives rise to neurons relaying afferent impulses to higher centres; in the adult such neurons compose the sensory nuclei of the spinal cord and brainstem. Synonym: lamina alaris, alar plate of neural tube, dorsolateral plate of neural tube, lamina dorsalis, wing plate. (05 Mar 2000) |
| acoustic crest | An elevation on the inner surface of the ampulla of each saemicircular duct; filaments of the vestibular nerve pass through the crista to reach hair cells on its surface; the hair cells are capped by the cupula, a gelatinous protein-polysaccharide mass. Synonym: crista ampullaris, acoustic crest, transverse septum. (05 Mar 2000) |
| acousticofacial crest | The part of the neural crest from which the ganglia of the seventh and eighth cranial nerves develop. (05 Mar 2000) |
| alveolar crest | The portion of the alveolar bone extending beyond the periphery of the socket, lying interproximally, the top of the residual alveolar bone. (05 Mar 2000) |
| ampullary crest | An elevation on the inner surface of the ampulla of each saemicircular duct; filaments of the vestibular nerve pass through the crista to reach hair cells on its surface; the hair cells are capped by the cupula, a gelatinous protein-polysaccharide mass. Synonym: crista ampullaris, acoustic crest, transverse septum. (05 Mar 2000) |
| anterior lacrimal crest | A vertical ridge on the lateral surface of the frontal process of the maxilla that forms part of the medial rim of the orbit. Synonym: crista lacrimalis anterior. (05 Mar 2000) |
| arched crest | The ridge on the anterior surface of the arytenoid cartilage that separates the triangular from the oblong fovea. Synonym: crista arcuata cartilaginis arytenoideae, arched crest, arcuate crest. (05 Mar 2000) |
| arcuate crest | The ridge on the anterior surface of the arytenoid cartilage that separates the triangular from the oblong fovea. Synonym: crista arcuata cartilaginis arytenoideae, arched crest, arcuate crest. (05 Mar 2000) |
| arcuate crest of arytenoid cartilage | The ridge on the anterior surface of the arytenoid cartilage that separates the triangular from the oblong fovea. Synonym: crista arcuata cartilaginis arytenoideae, arched crest, arcuate crest. (05 Mar 2000) |
| basilar crest of cochlear duct | An inward projection of the spiral ligament of the cochlea to which is attached the basilar membrane forming the floor of the cochlear duct. Synonym: crista basilaris ductus cochlearis. (05 Mar 2000) |
| buccinator crest | A ridge passing from the base of the coronoid process of the mandible to the region of the last molar tooth; it gives attachment to the mandibular part of the buccinator muscle. Synonym: crista buccinatoria. (05 Mar 2000) |
| cap of the ampullary crest | A gelatinous mass that overlies the hair cells of the ampullary crests of the saemicircular ducts; movement of endolymphatic fluid causes the cupula to move across the hair cells of the ampullary crest. Synonym: cap of the ampullary crest. (05 Mar 2000) |