| pyramidal process | The portion of the palatine bone passing lateral and posterior from the angle formed by the vertical and horizontal plates. Synonym: processus pyramidalis. (05 Mar 2000) |
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| pyramidal radiation | Corticospinal fibres passing from the cortex into the pyramid. Synonym: radiatio pyramidalis. (05 Mar 2000) |
| pyramidal tract | 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) |
| pyramidal tractotomy | May be mesencephalic (pedunculotomy or crusotomy), medullary (medullary pyramidotomy), or spinal (spinal pyramidotomy). (05 Mar 2000) |
| pyramidale | Synonym: triquetral bone. Origin: Mod. L. (05 Mar 2000) |
| pyramidalis | <anatomy, muscle> Origin, crest of pubis; insertion, lower portion of linea alba; action, makes linea alba tense; nerve supply, subcostal. Synonym: musculus pyramidalis, pyramidal muscle. (05 Mar 2000) |
| pyramidally | Like a pyramid. Source: Websters Dictionary (01 Mar 1998) |
| pyramidal muscle of auricle |
musculus pyramidalis auricularis.
출처: www.mercksource.com/pp/us/cns/cns_hl_dorlands.jspz...
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| pyramidal |
A pyramid is a geometric shape formed by connecting a polygonal base and a point, called the apex, by triangular faces. When unspecified the base is usually assumed to be square. One of the Platonic solids, the tetrahedron, is a triangular pyramid. The square and pentagonal pyramids can also be constructed with all faces regular, and so count among the Johnson solids. All pyramids are self-dual. ...
출처: en.wikipedia.org/wiki/Pyramidal
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| pyramidal neuron |
A class of neuron in the cerebral cortex with a pyramid-shaped cell body. These neurons send long axons down the spinal cord and form dendrites that extend laterally through the cortical layer that contains the cell body.
출처: www.nature.com/nrg/journal/v2/n9/glossary/nrg0901_...
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| pyramidal tract |
(noun) one of three descending tracts of the spinal cord. Consists of fibers arising from the giant pyramidal cells of Betz present in the motor area of the cerebral cortex
출처: www.orgsites.com/fl/adjuvantdisease/_pgg9.php3
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| pyramidal tract |
Carries the voluntary muscle messages from the brain.
출처: www.condell.org/libertyville/neurosurgery/neurolog...
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