| tractus centralis tegmenti | A large fibre bundle passing longitudinally through the central mesencephalic and pontine tegmentum, distinguished from adjacent longitudinal groups of fibre-fascicles of the reticular formation by a more compact composition. In transverse sections of the mesencephalon the bundle occupies a large triangular area lateral to the medial longitudinal fasciculus; farther caudally it expands ventralward and finally passes over the lateral side of the (inferior) olivary nucleus, becoming part of the latter's fibre capsule. The bundle contains fibres from the mesencephalic tegmentum and regions surrounding the central gray substance descending to the olivary nucleus; it also includes numerous fibres ascending from the medullary, pontine, and mesencephalic reticular formation to the thalamus and subthalamus region. Synonym: tractus tegmentalis centralis, central tegmental fasciculus, tractus centralis tegmenti. (05 Mar 2000) |
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| tractus cerebellorubralis | That component of the superior cerebellar peduncle (brachium conjunctivum) which distributes fibres within the red nucleus of the opposite side. Synonym: tractus cerebellorubralis. (05 Mar 2000) |
| tractus cerebellothalamicus | That component of the superior cerebellar peduncle (brachium conjunctivum) which originates in the cerebellar nuclei, crosses completely in the decussation of the brachia conjunctiva, bypasses the red nucleus, and terminates in parts of the ventral anterior, ventral intermediate, ventral posterolateral, and central lateral nuclei of the thalamus. Synonym: tractus cerebellothalamicus, dentatothalamic tract. (05 Mar 2000) |
| tractus corticobulbaris | <physiology> Collective term for those fibres (corticonuclear fibres) which separate from the corticospinal tract in the course of the latter's descent through the pons and medulla oblongata. Fibres of this tract innervate the motor nuclei of the trigeminal, facial, and hypoglossal nerves (perhaps also the nucleus ambiguus), directly and by way of interneurons in the lateral part of the rhombencephalic tegmentum. No direct supranuclear cortical innervation of the motor nuclei innervating the external eye muscles (oculomotor, trochlear, abducens) has been identified. Fibres of the corticobulbar tract also project into the formatio reticularis (i.e., corticoreticular fibres) and terminate upon sensory relay nuclei (e.g., gracile and cuneate nuclei, nucleus spinalis trigeminalis and nucleus solitarius). Synonym: tractus corticobulbaris. (05 Mar 2000) |
| tractus corticopontini | <anatomy, physiology> Collective term for the multitude of fibres which, originating in all of the major subdivisions of the cerebral cortex, descend in the internal capsule and crus cerebri to terminate in the nuclei of the ventral part of the pons. Individual components of this massive fibre system are indicated, according to their origin in the cerebral cortex, as the frontopontine tract, parietopontine tract, occipitopontine tract, and temporopontine tract. Synonym: tractus corticopontini. (05 Mar 2000) |
| tractus corticospinalis | A massive bundle of fibres originating from pyramidal cells of various sizes in the fifth layer of the precentral motor (area 4), the premotor area (area 6), and to a lesser extent from the postcentral gyrus. Cells of origin in area 4 include the gigantopyramidal cells of Betz. Fibres from these cortical regions descend through the internal capsule, the middle third of the crus cerebri, and the ventral part of the pons to emerge on the ventral surface of the medulla oblongata as the pyramis. Continuing caudally, most of the fibres cross to the opposite side in the pyramidal decussation and descend in the dorsal half of the lateral funiculus of the spinal cord as the lateral pyramidal tract, which distributes its fibres throughout the length of the spinal cord to interneurons of the zona intermedia of the spinal gray matter. In the (extremity-related) spinal cord enlargements, fibres also pass directly to motoneuronal groups that innervate distal extremity muscles subserving particular hand-and-finger or foot-and-toe movements. The uncrossed fibres form a small bundle, the anterior pyramidal tract, which descends in the anterior funiculus of the spinal cord and terminates in synaptic contact with interneurons in the medial half of the anterior horn on both sides of the spinal cord. Interruption of the pyramidal tract at or below its cortical origin causes impairment of movement in the opposite body-half, especially severe in the arm and leg; characterised by muscular weakness, spasticity and hyperreflexia, and a loss of discrete finger and hand movements. Babinski's sign is associated with this condition of hemiplegia. Synonym: tractus corticospinalis, tractus pyramidalis, corticospinal tract. (05 Mar 2000) |
| tractus corticospinalis anterior | Uncrossed fibres forming a small bundle in the pyramidal tract. See: pyramidal tract. Synonym: tractus corticospinalis anterior, tractus pyramidalis anterior, anterior corticospinal tract, anterior pyramidal fasciculus, direct pyramidal tract, fasciculus corticospinalis anterior, fasciculus pyramidalis anterior, Turck's bundle, Turck's column, Turck's tract. (05 Mar 2000) |
| tractus corticospinalis lateralis | Those fibres of the pyramidal tract that cross to the opposite side in the pyramidal decussation and descend in the dorsal half of the lateral funiculus of the spinal cord; they are distributed throughout the length of the spinal cord to interneurons of the zona intermedia of the spinal gray matter. See: pyramidal tract. Synonym: tractus corticospinalis lateralis, tractus pyramidalis lateralis, crossed pyramidal tract, fasciculus corticospinalis lateralis, fasciculus pyramidalis lateralis, lateral corticospinal tract, lateral pyramidal fasciculus. (05 Mar 2000) |
| tractus descendens nervi trigemini | <anatomy, nerve> A compact fibre bundle, comma-shaped on transverse section, composed of primary sensory fibres of the portio major of the trigeminal nerve, descending from the level of the entrance of the trigeminus in the upper pons down through the dorsolateral region of the rhombencephalic tegmentum along the lateral side of the descending or spinal nucleus of the trigeminus, emerging on the dorsolateral surface of the lower medulla oblongata as the tuberculum cinereum, and continuing as far as the second cervical segment of the spinal cord. Its fibres are distributed to the descending or spinal nucleus of the trigeminus. Synonym: tractus spinalis nervi trigemini, descending tract of trigeminal nerve, tractus descendens nervi trigemini. (05 Mar 2000) |
| tractus dorsolateralis | A longitudinal bundle of thin, unmyelinated and poorly myelinated fibres capping the apex of the posterior horn of the spinal gray matter, composed of posterior root fibres and short association fibres that interconnect neighboring segments of the posterior horn. Synonym: fasciculus dorsolateralis, tractus dorsolateralis, dorsolateral tract, fasciculus marginalis, Lissauer's bundle, Lissauer's column, Lissauer's fasciculus, Lissauer's marginal zone, Lissauer's tract, marginal fasciculus, Spitzka's marginal tract, Spitzka's marginal zone, Waldeyer's tract, Waldeyer's zonal layer. (05 Mar 2000) |
| tractus fastigiobulbaris | A fibre bundle originating in the fastigial nucleus (nucleus tecti) of both sides, passing out of the cerebellum in the inferior cerebellar peduncle (corpus restiforme), and distributing its fibres to the vestibular nuclei and other cell groups in the medulla oblongata. Prominent crossed fibres loop over the dorsal surface of the superior cerebellar peduncle before turning ventrally, forming the uncinate bundle of Russell. Synonym: tractus fastigiobulbaris. (05 Mar 2000) |
| tractus frontopontinus | A large group of fibres arising from the frontal lobe of the cerebral hemisphere, especially the precentral gyrus, descending in the capsula interna, farther caudally composing the medial part of the crus cerebri in which they extend caudalward to end in the gray matter (pontine nuclei) of the ventral part of the pons. Synonym: tractus frontopontinus. (05 Mar 2000) |
| tractus habenulopeduncularis | tractus habenulopeduncularis |
| tractus iliotibialis | A fibrous reinforcement of the fascia lata on the lateral surface of the thigh, extending from the crest of the ilium to the lateral condyle of the tibia. Synonym: tractus iliotibialis, iliotibial band, Maissiat's band. (05 Mar 2000) |
| tractus mesencephalicus nervi trigemini | <anatomy, nerve> Located alongside the central substance of the midbrain and composed of primary sensory fibres, the cells of origin of which compose the mesencephalic nucleus of the trigeminus. Synonym: tractus mesencephalicus nervi trigemini. (05 Mar 2000) |
| ventral spinocerebellar tract | A bundle of fibres originating in the base of the posterior horn and zona intermedia throughout lumbosacral segments of the spinal cord, crossing to the opposite side and ascending in a peripheral position in the ventral half of the lateral funiculus. In its ascent through the rhombencephalon, the tract curves sharply dorsalward along the rostral border of the trigeminal motor nucleus, entering the cerebellum in a caudal direction over the dorsal surface of the superior cerebellar peduncle, and terminating as mossy fibres in the granular layer of the cortex of the cerebellar vermis. The bundle conveys proprioceptive and exteroceptive information largely from the opposite lower extremity. Synonym: tractus spinocerebellaris anterior, Gowers' column, Gowers' tract, ventral spinocerebellar tract. (05 Mar 2000) |
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| ventral spinothalamic tract | The more anterior or ventral part of the spinothalamic tract that is involved in tactile sensation. See: spinothalamic tract. Synonym: tractus spinothalamicus anterior, ventral spinothalamic tract. (05 Mar 2000) |
| Marchi's tract | A bundle of thick, heavily myelinated fibres originating in the deep layers of the superior colliculus, crossing to the opposite side in the dorsal tegmental decussation, descending along the median plane, between the medial longitudinal fasciculus dorsally, the medial lemniscus ventrally, into the anterior funiculus of the spinal cord. The tract ends in the medial region of the anterior horn of the cervical spinal cord, and appears to be involved in head movements during visual and auditory tracking. Throughout its course in the brainstem it is accompanied by fibres of the tectobulbar tract. Synonym: tractus tectospinalis, Held's bundle, Loewenthal's bundle, Loewenthal's tract, Marchi's tract, predorsal bundle. (05 Mar 2000) |
| geniculocalcarine tract | The massive, fanlike fibre system passing from the lateral geniculate body of the thalamus to the visual cortex (striate or calcarine cortex, area 17 of Brodmann); the fibres follow the retrolenticular and sublenticular limbs of the internal capsule into the corona radiata but they curve back along the lateral wall of the temporal and occipital horns of the lateral ventricle to the striate cortex on the medial surface and pole of the occipital lobe. Synonym: radiatio optica, geniculocalcarine radiation, geniculocalcarine tract, Gratiolet's fibres, Gratiolet's radiation, occipitothalamic radiation, Wernicke's radiation. (05 Mar 2000) |
| genital tract | The genital passages of the urogenital apparatus. Synonym: genital duct. (05 Mar 2000) |
| genitourinary tract | Includes the kidneys, ureters, bladder and urethra. (27 Sep 1997) |
| parietopontine tract | A system of fibres originating in the parietal lobe of the cerebral hemisphere which descend in the internal capsule and lateral part of the crus cerebri to terminate in the pontine nuclei or ventral part of the pons. Synonym: tractus parietopontinus. (05 Mar 2000) |
| vestibulospinal tract | A somatopically organised fibre bundle originating from the lateral vestibular nucleus (nucleus of Deiters) which descends uncrossed into the anterior funiculus of the spinal cord lateral to the anterior median fissure; the tractus extends throughout the length of the cord, distributing fibres at all levels to the medial part of the anterior horn. Excitatory impulses conveyed by the vestibulospinal tract increase extensor muscle tone. Synonym: tractus vestibulospinalis, deiterospinal tract. (05 Mar 2000) |
| GI-tract secretions | <radiology> Organ Volume (ml/day) ----- --------------- Salivary glands 1500 Stomach 2500 Biliary system 500 Pancreas 1500 Intestine 1000 (12 Dec 1998) |
| GI-tract target lesion | <radiology> Metastatic melanoma, primary neoplasm, spindle cell tumour (benign or malignant), lymphoma, carcinoid, carcinoma, metastasis, breast carcinoma, lung carcinoma, renal carcinoma, Kaposi's sarcoma, eosinophilic granuloma, ectopic pancreas (12 Dec 1998) |
| medial root of optic tract | The smaller division of the posterior end of the optic tract that disappears under the medial geniculate body. Synonym: radix medialis tractus optici. (05 Mar 2000) |
| central tegmental tract | A large fibre bundle passing longitudinally through the central mesencephalic and pontine tegmentum, distinguished from adjacent longitudinal groups of fibre-fascicles of the reticular formation by a more compact composition. In transverse sections of the mesencephalon the bundle occupies a large triangular area lateral to the medial longitudinal fasciculus; farther caudally it expands ventralward and finally passes over the lateral side of the (inferior) olivary nucleus, becoming part of the latter's fibre capsule. The bundle contains fibres from the mesencephalic tegmentum and regions surrounding the central gray substance descending to the olivary nucleus; it also includes numerous fibres ascending from the medullary, pontine, and mesencephalic reticular formation to the thalamus and subthalamus region. Synonym: tractus tegmentalis centralis, central tegmental fasciculus, tractus centralis tegmenti. (05 Mar 2000) |
| respiratory tract | The air passages from the nose to the pulmonary alveoli, through the pharynx, larynx, trachea, and bronchi. (05 Mar 2000) |
| respiratory tract fistula | An abnormal passage communicating between any parts of the respiratory tract or between any part of the respiratory system and other organs. (12 Dec 1998) |
| cerebellorubral tract | That component of the superior cerebellar peduncle (brachium conjunctivum) which distributes fibres within the red nucleus of the opposite side. Synonym: tractus cerebellorubralis. (05 Mar 2000) |
| traction |
the use of tension to hold a body part in place or to correct or prevent an alignment problem
출처: www.american-depot.com/services/resources_gl_t.asp
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| tractor |
The tractor is the driver compartment and engine of the truck. It has two or three axles.
출처: www.epa.gov/smartway/glossary.htm
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| tract |
A parcel of land, generally held for subdividing and development into residential units.
출처: www.peakagents.ca/glossary/t8.htm
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| traction |
Friction of a body on a surface while moving.
출처: www.peakagents.ca/glossary/t8.htm
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| tractor |
A tracked vehicle used for a variety of construction and farming tasks.
출처: www.peakagents.ca/glossary/t8.htm
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| tract | the friction between a body and the surface on which it moves (as between an automobile tire and the road) |
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| tract | steam-powered locomotive for drawing heavy loads along surfaces other than tracks |
| tract | exerting traction and serving to pull |
| tract | a wheeled vehicle with large wheels |
| tract | a truck that has a cab but no body |
| tract | a truck consisting of a tractor and trailer together |