| segment polarity gene | <molecular biology> A segmentation gene, responsible for specifying anterior posterior polarity within individual embryonic segments. In Drosophila, there are at least 10 such genes, for example gooseberry. (18 Nov 1997) |
|---|---|
| neural segment | Alternate swellings and constrictions seen along the neuraxis at early stages of neural tube development, thought to be evidence of intrinsic segmentation in the CNS. Neuromeres or segments in the hindbrain region are called rhombomeres and have been shown to be lineage restriction units, each constructing a defined piece of hindbrain. (18 Nov 1997) |
| S-T segment | That part of the electrocardiographic tracing immediately following the QRS complex and merging into the T wave. (05 Mar 2000) |
| subapical segment | An inconstant segment of the inferior lobe of the right and left lungs. Synonym: segmentum subapicale, segmentum subsuperius, subsuperior segment. (05 Mar 2000) |
| subsuperior segment | An inconstant segment of the inferior lobe of the right and left lungs. Synonym: segmentum subapicale, segmentum subsuperius, subsuperior segment. (05 Mar 2000) |
| superior lingular segment | Superior lingular segment of the superior lobe of the left lung; lies above inferior lingular segment. Synonym: segmentum lingulare superius. (05 Mar 2000) |
| superior segment | The uppermost segment of the kidney. Synonym: apical segment. (05 Mar 2000) |
| sympathetic segment | A divison of the sympathetic trunks based on the origins of the gray communicating branches. (05 Mar 2000) |
| D gene segment | <molecular biology> Diversity gene segment. Part of the gene for the immunoglobin heavy chain, it codes for part of the hypervariable region of the VH domain and is located between the VH and JH segments. There are probably about 20 different D segments. (18 Nov 1997) |
| inferior lingular segment | Inferior lingular segment of superior lobe of left lung; between superior lingular segment and oblique fissure. Synonym: segmentum lingulare inferius. (05 Mar 2000) |
| inferior segment of kidney | Which typically consists of approximately the inferior third of the kidney viewed either anteriorly or posteriorly. Synonym: segmentum inferius. (05 Mar 2000) |
| interannular segment | The portion of a myelinated nerve fibre between two successive nodes. Synonym: interannular segment, internode, Ranvier's segment, segmentum internodale. (05 Mar 2000) |
| intermaxillary segment | The primordial mass of tissue formed by the merging of the medial nasal prominences of the embryo; it contributes to the intermaxillary portion of the upper jaw, the prolabial portion of the upper lip, and the primary palate. (05 Mar 2000) |
| internodal segment | The portion of a myelinated nerve fibre between two successive nodes. Synonym: interannular segment, internode, Ranvier's segment, segmentum internodale. (05 Mar 2000) |
| joining segment | <molecular biology> A small DNA segment that links genes to yield a functional gene encoding an immunoglobulin. (09 Oct 1997) |