segment


segment
1. A section; a part of an organ or other structure delimited naturally, artificially, or by invagination from the remainder. SYN: segmentum [TA]. SEE ALSO: metamere. 2. A territory of an organ having independent function, supply, or drainage. 3. To divide and redivide into minute equal parts. [L. segmentum, fr. seco, to cut]
- A1 s. of anterior cerebral artery precommunicating part of anterior cerebral artery.
- A2 s. of anterior cerebral artery postcommunicating part of anterior cerebral artery.
- abnormal ST s. SYN: isoelectric period.
- anterior s. [TA] a delimited part or section of an organ or other structure that lies in front of or ventral to the other similar parts or sections. See anterior (bronchopulmonary) s. [S III], anterior basal (bronchopulmonary) s. [S VIII], anterior inferior renal s., anterior superior renal s., anterior ocular s.. SYN: segmentum anterius [TA].
- anterior basal (bronchopulmonary) s. [S VIII] of the four bronchopulmonary segments of the inferior lobes of the right or left lung that contact the diaphragm, the one lying in front, i.e., nearest the costal cartilages; supplied by the anterior basal segmental bronchi [B VIII] and anterior basal segmental (pulmonary) artery. SYN: segmentum (bronchopulmonale) basale anterius [S VIII].
- anterior (bronchopulmonary) s. [S III] [TA] of the three bronchopulmonary segments comprising the upper lobe of the right or left lungs, the one that lies nearest the costal cartilages, supplied by the anterior segmental bronchis [B III] and anterior segmental (pulmonary) artery. SYN: segmentum (bronchopulmonale) anterius S III [TA].
- anterior inferior renal s. portion of the kidney exclusively supplied by the anterior inferior segmental (renal) artery. SYN: segmentum renale anterius inferius.
- anterior ocular s. portion of the eyeball comprised by the cornea, iris, and lens and the associated chambers (anterior and posterior), which are filled with aqueous humor. SYN: segmentum oculare anterius [TA].
- anterior superior renal s. [TA] portion of the kidney exclusively supplied by the anterior superior segmental (renal) artery. SYN: segmentum renale anterius superius.
- apical (bronchopulmonary) s. [S I] of the three bronchopulmonary segments comprising the superior lobe of the right lung, the one extending to the highest level (into the cervical parietal pleura) that is supplied by the apical segmental bronchus [B I] and the apical segmental (pulmonary) artery. SYN: segmentum bronchopulmonale apicale S I.
- apicoposterior (bronchopulmonary) s. [SI + SII] of the four bronchopulmonary segments typically comprising the superior lobe of the left lung, the most superior and posterior, supplied by the left apicoposterior segmental bronchus [B I + II]; they correspond approximately in position to the separate apical and posterior bronchopulmonary segments of the superior lobe of the right lung. SYN: segmentum (bronchopulmonale) apicoposterius [SI + II].
- arterial segments of kidney SYN: renal segments.
- segmentum bronchopulmonale basale posterius S X [TA] SYN: posterior basal bronchopulmonary s. S X.
- bronchopulmonary s. [TA] smallest surgically resectable subdivision of the lobes of the lungs, supplied exclusively by a tertiary (segmental) bronchus and the corresponding tertiary branch of the pulmonary artery (segmental pulmonary artery); typically, the right lung has ten bronchopulmonary segments, and the left has eight or nine due to a merging of the apical and posterior segments of the upper lobe and of the anterior and medial basal segments of the lower lobe. SYN: segmentum bronchopulmonale [TA].
- cardiac s. SYN: medial basal bronchopulmonary s. S VII.
- cervical segments of spinal cord [C1–C8] cervical part of spinal cord.
- coccygeal s. of spinal cord [Co] inferiormost s. of spinal cord that gives rise to the coccygeal pair of spinal nerves and constitutes the coccygeal part of the spinal cord. SYN: segmentum medullae spinalis coccygeum [Co] [TA].
- hepatic segments [TA] surgically resectable portions of the liver supplied by independent branches of the portal vein and hepatic artery, and drained by independent lobular branches of the hepatic bile ducts; thus, the naming and numbering of the eight hepatic segments in TA is based on the portobilioarterial distribution : posterior , [i]lateral [II], left lateral anterior [III], and medial [IV] segments of the left (part of) liver, and anterior medial [V], right anterior lateral [VI], posterior lateral [VII], and posterior medial [VIII] segments of the right (part of) liver; the hepatic segments are separated by the vertical planes of the three major (right, intermediate, and left) hepatic veins; those of the right (part of) liver are also separated by the horizontal plane of the right division of the portobilioarterial tree. See anterior s., lateral s., medial s., posterior s.. SYN: segmenta hepatis [TA], segments of liver.
- s. I posterior hepatic s. I.
- inferior s. [TA] a delimited part or section of an organ or other structure that lies at the lowest level (nearest the feet) compared with the other similar parts or sections. SYN: segmentum inferius [TA].
- inferior lingular (bronchopulmonary) s. [S V] of the four bronchopulmonary segments that typically comprise the superior lobe of the left lung, the most inferior, supplied by the inferior lingular bronchus [B V] and inferior lingular segmental (pulmonary) artery; corresponds approximately in position to the medial [S V] s. of the middle lobe of the right lung; the lingula is a feature of this part of the left lung. SYN: segmentum lingulare bronchopulmonale inferius S V [TA].
- inferior renal s. portion of the kidney exclusively supplied by the inferior segmental (renal) artery. SYN: segmentum renale inferius [TA].
- interannular s. SYN: internodal s..
- intermaxillary s. 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.
- internodal s. the portion of a myelinated nerve fiber between two successive nodes. SYN: interannular s., internode, Ranvier s., segmentum internodale.
- Lanterman segments the divisions of the nerve fiber between the Schmidt-Lanterman incisures.
- lateral s. [TA] a delimited part or section of an organ or other structure that lies farthest to the left or right compared with the other similar parts or sections. See lateral bronchopulmonary s. S IV, lateral basal (bronchopulmonary) s. [S IX], (left anterior) lateral hepatic s. [III], (left posterior) lateral hepatic s. III, right anterior lateral hepatic s. [VI], (right) posterior lateral hepatic s. [VII]. SYN: segmentum laterale [TA].
- lateral basal (bronchopulmonary) s. [S IX] of the four bronchopulmonary segments of the inferior lobes of the right or left lung that contact the diaphragm, the one lying farthest to the right in the right lung, and farthest to the left in the left lung, supplied by the lateral basal segmental bronchi [B IX] and lateral basal segmental (pulmonary) artery. SYN: segmentum (bronchopulmonale) basale laterale [S IX].
- lateral bronchopulmonary s. S IV [TA] of the two bronchopulmonary segments comprising the middle lobe of the right lung, the one placed on the right side that is supplied by the lateral segmental bronchus [B IV] and the lateral segmental (pulmonary) artery. SYN: segmentum bronchopulmonale laterale S IV [TA].
- (left anterior) lateral hepatic s. [III] [TA] one of the three hepatic segments that constitute the left (part of) liver, the one which lies to the left of the inferior portion of the falciform ligament, typically overlapping the stomach anteriorly, supplied by the lower lateral branch from the umbilical part of the left branch of the hepatic portal vein. SYN: lateral inferior hepatic area [TA], segmentum hepatis anterius laterale sinistrum [III] [TA], segmentum III.
- (left) medial hepatic s. [IV] [TA] of the three hepatic segments that constitute the left (part of) liver, the one that lies to the right of the falciform ligament; it lies between that ligament and the vertical plane of the right hepatic vein, that is demarcated on the diaphragmatic surface of the liver by a line extrapolated from the fossa for the gallbladder to the inferior vena cava; the quadrate lobe of the visceral surface of the liver is also part of the medial hepatic s.; the medial s. is supplied by medial branches of the umbilical part of the left branch of the portal vein. SYN: segmentum hepatis mediale (sinistrum) [IV] [TA], segmentum IV.
- (left posterior) lateral hepatic s. III [TA] of the three hepatic segments that constitute the left (part of) liver, the one that lies to the left of the superior portion of the falciform ligament and the fissure for the ligamentum venosum; typically, it lies superior to the stomach and is supplied by the upper lateral branch from the umbilical part of the left branch of the hepatic portal vein. SYN: lateral superior hepatic area [TA], segmentum hepatis posterius laterale sinistrum [II] [TA], segmentum II.
- segments of liver SYN: hepatic segments.
- lower uterine s. the inferior portion or isthmus of the uterus, the lower extremity of which joins with the cervical canal and, during pregnancy, expands to become the lower part of the uterine cavity. This is not the active contracting portion of the uterus.
- lumbar segments L1–L5 of spinal cord SYN: lumbar part of spinal cord.
- lumbar segments of spinal cord L1–5 the five segments of the spinal cord that give rise to the five pairs of lumbar spinal nerves [L1–L5] and constitute the lumbar part of the spinal cord, that in the adult, lies within the portion of the vertebral canal formed by the T11–L1 vertebrae. SYN: segmenta medullae spinalis lumbaria L1–L5.
- medial s. [TA] a delimited part or section of an organ or other structure that lies closest to the midline compared with the other similar parts or sections. See medial bronchopulmonary s. S V, medial basal bronchopulmonary s. S VII, (left) medial hepatic s. [IV], (right) posterior medial hepatic s. [VIII], (right) anterior medial hepatic s. [V]. SYN: segmentum mediale [TA].
- medial basal bronchopulmonary s. S VII [TA] of the four bronchopulmonary segments of the inferior lobes of the right or left lung that contact the diaphragm, the one lying directly inferior to the hilum of the lung in contact with the middle of the lateral aspect of the mediastinum, supplied by the medial basal segmental bronchis [B VII] and medial basal segmental (pulmonary) artery. SYN: segmentum bronchopulmonale basale mediale S VII [TA], cardiac s., segmentum cardiacum.
- medial bronchopulmonary s. S V [TA] of the two bronchopulmonary segments comprising the middle lobe of the right lung, the one placed on the left that is supplied by the medial segmental bronchus [B V] and the medial segmental (pulmonary artery). SYN: segmentum bronchopulmonale mediale S V [TA].
- mesoblastic s. SYN: somite.
- M2 s. of middle cerebral artery terminal branches of middle cerebral artery, under branch.
- neural s. SYN: neuromere.
- posterior s. [TA] a delimited part or section of an organ or other structure that lies in back of or dorsal to the other similar parts or sections. See posterior bronchopulmonary s. S II, posterior basal bronchopulmonary s. S X, posterior hepatic s. I, (right) posterior lateral hepatic s. [VII], (right) posterior medial hepatic s. [VIII], posterior renal s.. SYN: segmentum posterius [TA].
- posterior basal bronchopulmonary s. S X [TA] of the four bronchopulmonary segments of the inferior lobes of the right or left lung that contact the diaphragm, the one lying nearest the vertebral column, supplied by the posterior basal segmental bronchus [B X] and posterior basal segmental (pulmonary) artery. SYN: segmentum bronchopulmonale basale posterius S X [TA].
- posterior bronchopulmonary s. S II [TA] of the three bronchopulmonary segments comprising the upper lobe of the right lungs, the one that lies nearest the vertebral column, supplied by the posterior segmental bronchus [B II] and posterior segmental (pulmonary) artery. SYN: segmentum bronchopulmonale posterius S II [TA].
- posterior hepatic s. I [TA] the relatively small part of the liver supplied by caudate branches of the left (or left and right) branches of the portal vein, demarcated on the visceral surface of the liver as the caudate lobe. SYN: segmentum hepatis posterius I [TA], caudate lobe, lobus caudatus, posterior liver, posterior part of liver, s. I, segmentum I, Spigelius lobe.
- posterior renal s. [TA] part of the kidney exclusively supplied by the posterior segmental (renal) artery. SYN: segmentum renale posterius [TA].
- P1 s. of posterior cerebral artery SYN: precommunicating part of posterior cerebral artery.
- P2 s. of posterior cerebral artery postcommunicating part of posterior cerebral artery.
- P3 s. of posterior cerebral artery [TA] SYN: lateral occipital artery.
- PR s. that part of the electrocardiographic curve between the end of the P wave and the beginning of the QRS complex.
- precommunical s. of anterior cerebral artery SYN: precommunicating part of anterior cerebral artery.
- precommunical s. of posterior cerebral artery SYN: precommunicating part of posterior cerebral artery.
- Ranvier s. SYN: internodal s..
- renal segments [TA] regions of the kidney supplied by end arteries branching from the renal arteries; they are named anterior inferior s., anterior superior s., inferior s., posterior s., and superior s.. SYN: segmenta renalia [TA], arterial segments of kidney.
- right anterior lateral hepatic s. [VI] [TA] of the four segments comprising the right (part of) liver (i.e., that lie to the right side of the plane of the middle hepatic vein), the one that also lies to the right of the plane of the right hepatic vein and inferior to the plane of the transverse portion of the right branch of the hepatic portal vein; it is supplied by the lateral anterior branch of the portal vein. SYN: segmentum hepatis anterius laterale dextrum [VI] [TA].
- (right) anterior medial hepatic s. [V] [TA] of the four segments comprising the right (part of) liver (i.e., that lie to the right side of the plane of the middle hepatic vein), the one that lies between that plane and the plane of the right hepatic vein and inferior to the plane of the transverse portion of the right branch of the hepatic portal vein; it is supplied by the medial anterior branch of the portal vein. SYN: segmentum hepatis anterius mediale (dextrum) [V] [TA].
- (right) posterior lateral hepatic s. [VII] [TA] of the four segments comprising the right (part of) liver (i.e., that lie to the right side of the plane of the middle hepatic vein), the one that also lies to the right of the plane of the right hepatic vein and superior to the plane of the transverse portion of the right branch of the hepatic portal vein; it is supplied by the lateral posterior branch of the portal vein. SYN: segmentum hepatis posterius laterale (dextrum) [VII] [TA].
- (right) posterior medial hepatic s. [VIII] [TA] of the four segments comprising the right (part of) liver (i.e., that lie to the right side of the plane of the middle hepatic vein), the one that lies between that plane and the plane of the right hepatic vein and superior to the plane of the transverse portion of the right branch of the hepatic portal vein; it is supplied by the medial posterior branch of the portal vein. SYN: segmentum hepatis posterius mediale (dextrum) [VIII] [TA].
- RST s. the part of the electrocardiogram between the QRS complex and the T wave. Virtually never distinct in normal hearts in which it forms the initial limb of the T wave without an agreed endpoint. SYN: ST s..
- segments of spinal cord [C1–Co] [TA] one of the 31 portions of the spinal cord, each of which gives rise to the anterior and posterior roots that combine to form a single pair of spinal nerves. These are the cervical spinal cord segments [C1–C8]; the thoracic spinal cord segments [T1–T12]; the lumbar spinal cord segments [L1–L5]; the sacral spinal cord segments [S1–S5], and the coccygeal spinal cord s. [Co]. SYN: segmenta medullae spinalis C1–Co [TA].
- segments of spleen splenic territories receiving independent arterial supply or drained by independent roots of the splenic vein. SYN: segmenta lienis.
- ST s. SYN: RST s..
- subapical s. an inconstant s. of the inferior lobe of the right and left lungs. SYN: segmentum subapicale, segmentum subsuperius, subsuperior s..
- subsuperior s. SYN: subapical s..
- superior s. the uppermost s. of the kidney;
- superior lingular bronchopulmonary s. S IV [TA] of the four bronchopulmonary segments that typically comprise the superior lobe of the left lung, the s. that lies centrally and posteriorly, supplied by the superior lingular bronchus [B IV] and superior lingular segmental (pulmonary) artery; corresponds approximately in position to the lateral [S IV] s. of the middle lobe of the right lung. SYN: segmentum bronchopulmonale lingulare superius[S IV] [TA].
- superior renal s. [TA] portion of the kidney exclusively supplied by the superior segmental (renal) artery. SYN: segmentum renale superius [TA].
- sympathetic s. a divison of the sympathetic trunks based on the origins of the gray communicating branches.
- upper uterine s. the main portion of the body of the gravid uterus, the contraction of which furnishes the chief force of expulsion in labor.
- venous segments of the kidney anatomic segments of the kidney drained by tributaries of the renal vein; not a true segmental distribution, since cross communication exists between the various tributaries within the kidney.

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seg·ment 'seg-mənt n one of the constituent parts into which a body, entity, or quantity is divided or marked off by or as if by natural boundaries <bronchopulmonary \segments> <the affected \segment of the colon was resected>
seg·ment 'seg-.ment vt
1) to cause to undergo segmentation by division or multiplication of cells
2) to separate into segments

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n.
(in anatomy) a portion of a tissue or organ, usually distinguishable from other portions by lines of demarcation. For example, the uterus consists of upper and lower segments. The anterior segment of the eye is the front portion, including the cornea, anterior chamber, iris, and lens. See also somite.

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seg·ment (segґmənt) [L. segmentum a piece cut off] a portion of a larger body or structure, set off by natural or arbitrarily established boundaries. See also segmentum.

Medical dictionary. 2011.

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  • segment — [ sɛgmɑ̃ ] n. m. • 1536; lat. segmentum, de secare « couper » 1 ♦ Portion, partie détachée d un ensemble. ♢ Math. Segment de droite : ensemble des points d une droite compris entre deux points donnés de la droite. Segment de sphère ou sphérique …   Encyclopédie Universelle

  • segment — SEGMÉNT, (1, 2, 3) segmente, s.n., (4) segmenţi, s.m. 1. s.n. Porţiune dintr o figură, limitată cel puţin într o parte de marginile ei. ♢ Segment de dreaptă = porţiune dintr o dreaptă mărginită de două puncte. Segment de cerc = parte dintr un… …   Dicționar Român

  • Segment — may mean: *an internal section of a citrus fruit *Market segment, the smaller subgroups comprising a marketComputing *Memory segment, the portion of computer memory which may be addressed by a single index register *Image segment created in… …   Wikipedia

  • Segment — Seg ment, n. [L. segmentum, fr. secare to cut, cut off: cf. F. segment. See {Saw} a cutting instrument.] 1. One of the parts into which any body naturally separates or is divided; a part divided or cut off; a section; a portion; as, a segment of… …   The Collaborative International Dictionary of English

  • Segment — Sn Teil, Abschnitt erw. fach. (16. Jh.) Entlehnung. Entlehnt aus l. sēgmentum, zu l. secāre (sectum) schneiden, abtrennen . Verb: segmentieren.    Ebenso nndl. segment, ne. segment, nfrz. segment, nschw. segment, nnorw. segment; sezieren. ✎ DF 4… …   Etymologisches Wörterbuch der deutschen sprache

  • Segment — (lateinisch segmentum ‚Abschnitt‘) bedeutet „Ausschnitt, Teil (eines Ganzen)“ und bezeichnet: in der Anatomie grundsätzlich gleichartig aufgebaute Körperabschnitte wie die Segmente der Gliedertiere (Ringelwürmer und Gliederfüßer) oder die… …   Deutsch Wikipedia

  • segment — sègment (segmȅnt) m <G mn nātā> DEFINICIJA 1. mat. dužina, posebno na realnom brojevnom pravcu 2. zool. podijeljenost tijela nekih životinja na veći ili manji broj metamera (kolutića); jedan za drugim slijede uzdužnu os tijela 3. dio čega;… …   Hrvatski jezični portal

  • Segment Y — is a Dutch automotive intelligence company that focuses on emerging markets. Operating from India, Segment Y covers emerging markets in Asia such as China, Thailand, Malaysia, India, Indonesia, Philippines and Vietnam.ervices and… …   Wikipedia

  • segment — {{/stl 13}}{{stl 8}}rz. mnż I, D. u, Mc. segmentncie {{/stl 8}}{{stl 20}} {{/stl 20}}{{stl 12}}1. {{/stl 12}}{{stl 7}} powtarzająca się część składowa jakiegoś urządzenia, budowli, zespołu maszyn itp., mogąca stanowić pod pewnym względem… …   Langenscheidt Polski wyjaśnień

  • Segment — Seg ment, v. i. (Biol.) To divide or separate into parts in growth; to undergo segmentation, or cleavage, as in the segmentation of the ovum. [1913 Webster] …   The Collaborative International Dictionary of English

  • Segment — (v. lat.), 1) so v.w. Kreisabschnitt, s. Abschnitt 1), vgl. Kreis 1); 2) (Archit.), die kleineren im Anstrich angebrachten Verzierungen (Opera segmentata), welche theils rund, theils eckig waren; hiernach Segmenta scutulata, S. trigona etc.; 3)… …   Pierer's Universal-Lexikon


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