| 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 |
| SDCN | N-syndectan, neural syndectan |
| SEGNE | secretory granules of neural and endocrine [cells] |
| neural tube | <embryology> The progenitor of the central nervous system. See: neural plate, neurulation. (18 Nov 1997) |
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| 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) |
| alveolar ridge | That portion of bone in either the maxilla or the mandible which surrounds and supports the teeth. (12 Dec 1998) |
| alveolar ridge augmentation | Preprosthetic surgery involving rib, cartilage, or iliac crest bone grafts, usually autologous, or synthetic implants for rebuilding the alveolar ridge. (12 Dec 1998) |
| apical ectodermal ridge | The layer of surface ectodermal cells at the apex of the embryonic limb bud; considered to exert an inductive influence on the condensation of underlying mesenchyme. (05 Mar 2000) |
| basal ridge | That portion of bone in either the maxilla or the mandible which surrounds and supports the teeth. (12 Dec 1998) |
| buccocervical ridge | A convexity within the cervical third of the buccal surface of molars. (05 Mar 2000) |
| buccogingival ridge | A distinct ridge on the buccal surface of a deciduous molar tooth, approximately 1.5 mm from the crown-root junction. (05 Mar 2000) |
| bulbar ridge | One of two spiral subendocardial thickenings in the embryonic bulbus cordis; when they fuse, they divide the bulbus into the aorta and pulmonary artery. (05 Mar 2000) |
| bulboventricular ridge | An elevation on the inner surface of the embryonic heart at four to five weeks; it indicates the division between the developing ventricles and the bulbus cordis. (05 Mar 2000) |
| palatine ridge | A rather narrow, low elevation in the centre of the hard palate that extends from the incisive papilla posteriorly over the entire length of the mucosa of the hard palate. Synonym: raphe palati, palatine ridge. (05 Mar 2000) |
| ganglion ridge | A group of embryonic cells that separate from the neural plate during neurulation and migrate to give several different lineages of adult cells: the spinal and autonomic ganglia, the glial cells of the peripheral nervous system and nonneuronal cells, such as chromaffin cells, melanocytes and some haemopoietic cells. (18 Nov 1997) |
| mammary ridge | Bandlike thickening of ectoderm in the embryo extending on either side from just below the axilla to the inguinal region; in human embryos, the mammary glands arise from primordia in the thoracic part of the ridge, the balance of the ridge disappearing; in some lower mammals which give birth to a litter of young, several milk glands develop along these lines. Synonym: mammary fold, milk line, milk ridge. (05 Mar 2000) |