junction
The point, line, or surface of union of two parts, mainly bones or cartilages. SYN: juncture. SYN: junctura (2) [TA], junctio.
- adhering junctions intercellular junctions, including zonulae adherentes, hemidesmosomes, and desmosomes, that primarily serve to bind cells together physically.
- amelodental j., amelodentinal j. rarely used terms for dentinoenamel j..
- amnioembryonic j. the line of amnionic attachment to the periphery of the embryonic disk.
- anorectal j. [TA] transition from rectum to anal canal; corresponds to the perineal flexure, or the level at which the gut perforates the pelvic diaphragm; here the rectal ampulla narrows abruptly into a narrow slip. SYN: junctio anorectalis [TA].
- AV j. imprecisely defined zone surrounding and including the AV node and the adjacent atrial and ventricular myocardium.
- cardioesophageal j. SYN: esophagogastric j..
- cementodentinal j. the surface at which the cementum and dentin of the root of a tooth are joined. SYN: dentinocemental j..
- cementoenamel j. the surface at which the enamel of the crown and the cementum of the root of a tooth are joined. SEE ALSO: cervical line.
- choledochoduodenal j. that part of the duodenal wall traversed by the ductus choledochus, ductus pancreaticus, and ampulla.
- communicating j. SYN: gap j..
- corneoscleral j. SYN: corneal limbus.
- costochondral junctions SYN: costochondral joints, under joint.
- dentinoenamel j. the surface at which the enamel and the dentin of the crown of a tooth are joined.
- duodenojejunal j. point along the course of the gastrointestinal tract where the duodenum ends and the jejunum begins; occurs approximately at the level of the L2 vertebra, 2–3 cm to the left of the midline; usually takes the form of an acute angle, the duodenojejunal flexure, and is supported by the attachment of the suspensory muscle (ligament) of the duodenum. SEE ALSO: duodenojejunal flexure.
- electrotonic j. SYN: gap j..
- esophagogastric j. terminal end of esophagus and beginning of stomach at the cardiac orifice; site of the physiologic inferior esophageal sphincter. SYN: cardioesophageal j..
- gap j. 1. an intercellular j. formerly considered to be a tight, membrane-to-membrane j. (macula occludens) but now shown to have a 2-nm gap between apposed cell membranes; the gap is not void but contains subunits in the form of polygonal lattices; it occurs in epithelia, between certain nerve cells, and in smooth and cardiac muscle; it is believed to mediate electrotonic coupling which allows ionic currents to pass from one cell to another. SEE ALSO: synapse. 2. areas of increased electrochemical communication between myometrial cells which aid in the propagation of the contractions of labor. SYN: communicating j., electrotonic j., electrotonic synapse, macula communicans, nexus.
- Holliday j. the cross-strand structure formed when two DNA duplexes cross in a recombination event. SYN: Holliday structure.
- ileocecal j. point along the course of the gastrointestinal tract where the small intestine (ileum) ends as it opens into the cecal portion of the large intestine; occurs usually within the iliac fossa, demarcated internally as the ileocecal orifice.
- impermeable j. SYN: zonula occludens.
- intercellular junctions specializations of the cellular margins that contribute to the adhesion or allow for communication between cells; they include the macula adherens (desmosome), zonula adherens, zonula occludens, and nexus (gap j.).
- intermediate j. SYN: zonula adherens.
- j. of lips SYN: commissure of lips.
- manubriosternal j. SYN: sternal angle.
- muscle-tendon j. SYN: muscle-tendon attachment.
- myoneural j. the synaptic connection of the axon of the motor neuron with a muscle fiber. See motor endplate. SYN: neuromuscular j..
- neuroectodermal j. the margin of the embryonic neural plate separating it from the embryonic surface ectoderm; cells from this region form the neural crest. SYN: neurosomatic j..
- neuromuscular j. SYN: myoneural j..
- neurosomatic j. SYN: neuroectodermal j..
- rectosigmoid j. the site at which the sigmoid colon becomes the rectum; usually takes the form of an acute angle, demarcated externally by a discontinuation of appendices epiploicae, a spreading out of the teniae coli to completely encircle the rectum, and consequently, termination of the sacculations (haustrae) between the teniae.
- right splicing j. boundary between the right end of an intron and the left end of the adjacent exon. SYN: acceptor splicing site.
- sclerocorneal j. SYN: corneal limbus.
- squamocolumnar j. the site of transition from stratified squamous epithelium to columnar epithelium, usually characterized by stratified coboidal epithelium.
- ST j. SYN: J point.
- sternomanubrial j. SYN: manubriosternal symphysis.
- tight j. SYN: zonula occludens.
- tympanostapedial j. SYN: tympanostapedial syndesmosis.
- ureteropelvic j. (UPJ) site of origin of the ureter from the renal pelvis, a common location for congenital or acquired obstruction.
- ureterovesical j. the site of entry of the ureter into the bladder, with an oblique angulation through the detrusor to avoid reflux. SEE ALSO: vesicoureteral reflux.

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junc·tion 'jəŋ(k)-shən n a place or point of meeting <the structure of the synaptic \junction as revealed by electron microscopy> see NEUROMUSCULAR JUNCTION
junc·tion·al -shnəl, -shən-əl adj

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n.
(in anatomy) the point at which two different tissues or structures are in contact. See also neuromuscular junction.

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junc·tion (junkґshən) [L. junctus past part. of jungere to join] the place of meeting or of coming together, as of two different organs or types of tissue. junctional adj

Medical dictionary. 2011.

Synonyms:

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  • Junction — may refer to:*Junction (traffic) where several traffic routes cross: **junction (rail), a railroad/railway junction **Intersection (road), a road junction **Interchange (road), a motorway junction *The Junction, a Toronto neighbourhood *The… …   Wikipedia

  • Junction — puede referirse a: Junction (Illinois), villa en el condado de Gallatin, estado estadounidense de Illinois. Junction (Texas), ciudad en el condado de Kimble, estado estadounidense de Texas. Junction (Utah), localidad del condado de Piute, estado… …   Wikipedia Español

  • Junction — Junction, IL U.S. village in Illinois Population (2000): 139 Housing Units (2000): 75 Land area (2000): 0.887141 sq. miles (2.297684 sq. km) Water area (2000): 0.000000 sq. miles (0.000000 sq. km) Total area (2000): 0.887141 sq. miles (2.297684… …   StarDict's U.S. Gazetteer Places

  • junction — junction, confluence, concourse are comparable when meaning the act, state, or place of meeting or uniting. Junction, the most general of these words, applies to the meeting or uniting usually of material things (as roads, rivers, lines, or… …   New Dictionary of Synonyms

  • Junction — ist die Bezeichnung mehrerer Orte in den Vereinigten Staaten: Junction (Illinois) Junction (Texas) Junction (Utah) Junction Township (Kansas) Siehe auch: Junction City Symbolische Verknüpfung mit Kommandozeilenbefehl JUNCTION.EXE erstellen …   Deutsch Wikipedia

  • Junction — Junc tion, n. [L. junctio, fr. jungere, junctum, to join: cf. F. jonction. See {Join}.] [1913 Webster] 1. The act of joining, or the state of being joined; union; combination; coalition; as, the junction of two armies or detachments; the junction …   The Collaborative International Dictionary of English

  • Junction, IL — U.S. village in Illinois Population (2000): 139 Housing Units (2000): 75 Land area (2000): 0.887141 sq. miles (2.297684 sq. km) Water area (2000): 0.000000 sq. miles (0.000000 sq. km) Total area (2000): 0.887141 sq. miles (2.297684 sq. km) FIPS… …   StarDict's U.S. Gazetteer Places

  • Junction, TX — U.S. city in Texas Population (2000): 2618 Housing Units (2000): 1222 Land area (2000): 2.286429 sq. miles (5.921824 sq. km) Water area (2000): 0.006923 sq. miles (0.017931 sq. km) Total area (2000): 2.293352 sq. miles (5.939755 sq. km) FIPS code …   StarDict's U.S. Gazetteer Places

  • Junction, UT — U.S. town in Utah Population (2000): 177 Housing Units (2000): 104 Land area (2000): 14.380676 sq. miles (37.245777 sq. km) Water area (2000): 0.579905 sq. miles (1.501948 sq. km) Total area (2000): 14.960581 sq. miles (38.747725 sq. km) FIPS… …   StarDict's U.S. Gazetteer Places

  • junction — junction, juncture A junction is a point at which two or more things are joined, and usually refers to physical objects. It has the special meaning of ‘a point at which roads or railway lines meet or cross’. Juncture occurs principally in the… …   Modern English usage

  • junction — [juŋk′shən] n. [L junctio < jungere, to JOIN] 1. a joining or being joined 2. a place or point of joining or crossing, as of highways or railroads 3. an interface between materials having different characteristics, as the pn junction in a… …   English World dictionary

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