| trophic nucleus | The larger nucleus (or sometimes nuclei) in ciliate protozoans. Derived from the micronucleus by a process of DNA polytenisation. The DNA in the macronucleus is actively transcribed. The macronucleus degenerates before conjugation. (18 Nov 1997) |
|---|---|
| tubercle of nucleus gracilis | tubercle of gracile nucleus |
| external cuneate nucleus | A cell group lateral to the cuneate nucleus which receives posterior-root fibres corresponding to the proprioceptive innervation of the arm and hand; it projects to the cerebellum by way of the cuneocerebellar tract, and can be considered the upper-extremity equivalent of the thoracic nucleus. Synonym: nucleus cuneatus accessorius, external cuneate nucleus, lateral cuneate nucleus, Monakow's nucleus. (05 Mar 2000) |
| facial motor nucleus | A group of motor neurons located in the ventrolateral region of the lower pontine tegmentum and innervating the facial muscles, the stapedius muscle in the middle ear, the posterior limb of the musculus digastricus, and the stylohyoid muscle. Synonym: nucleus nervi facialis, facial motor nucleus, motor nucleus of facial nerve, nucleus facialis. (05 Mar 2000) |
| facial nucleus | A group of motor neurons located in the ventrolateral region of the lower pontine tegmentum and innervating the facial muscles, the stapedius muscle in the middle ear, the posterior limb of the musculus digastricus, and the stylohyoid muscle. Synonym: nucleus nervi facialis, facial motor nucleus, motor nucleus of facial nerve, nucleus facialis. (05 Mar 2000) |
| fastigial nucleus | The most medial of the cerebellar nuclei, lying medial to the interpositus nucleus, near the midline, in the white matter underneath the vermis of the cerebellar cortex. It receives the axons of Purkinje cells from all parts of the vermis. Its major projection is to the vestibular nuclei and medullary reticular formation. Synonym: nucleus fastigii, fastigatum, nucleus tecti, roof nucleus, tectal nucleus. (05 Mar 2000) |
| filiform nucleus | A triangular group of large magnocellular neurons in the periventricular zone of the anterior half of the hypothalamus. The cells of the nucleus are similar to those of the supraoptic nucleus; the axons of about 20% of their number join in the formation of the supraopticohypophysial tract and are functionally associated with the posterior lobe of the hypophysis; they project fibres to the brainstem nuclei (dorsal motor nucleus and solitary nucleus) and to the intermediolateral cell column of the spinal cord at thoracic, lumbar, and spinal levels; similar descending autonomic fibres arise from the lateral and posterior hypothalamic nuclei. Synonym: nucleus paraventricularis, filiform nucleus, nucleus filiformis. (05 Mar 2000) |
| lens nucleus, crystalline | The core of the crystalline lens, surrounded by the cortex. (12 Dec 1998) |
| lenticular nucleus | Lentiform nucleus, the large cone-shaped mass of gray matter forming the central core of the cerebral hemisphere. The convex base of the cone, oriented laterally and rostrally, is formed by the putamen which together with the caudate nucleus composes the striatum; the apical part, oriented medially and caudally, consists of the two segments of the globus pallidus. The nucleus is ventral and lateral to the thalamus and caudate nucleus, from which it is separated by the internal capsule, and together with the caudate nucleus composes the striate body. Synonym: nucleus lentiformis, lenticula. (05 Mar 2000) |
| Amberg's lateral sinus line | A line dividing the angle formed by the anterior edge of the mastoid process and the temporal line. (05 Mar 2000) |
| amyotrophic lateral sclerosis | A serious neurologic disease that results from the progressive degeneration of the motor neurons. (27 Sep 1997) |
| amyotropic lateral sclerosis | A chronic progressive disease of motor neurons (the nerves that come from the spinal cord to supply electrical energy to the muscles). (12 Dec 1998) |
| anterior lateral malleolar artery | <anatomy, artery> Origin, anterior tibial; distribution, ankle joint; anastomoses, peroneal, lateral tarsal. Synonym: arteria malleolaris anterior lateralis. (05 Mar 2000) |
| bulb of lateral ventricle | A rounded elevation in the dorsal part of the medial wall of the posterior horn of the lateral ventricle, produced by the major forceps. (05 Mar 2000) |
| bulb of posterior horn of lateral ventricle of brain | Bulb of posterior horn of lateral ventricle of the brain; a curved elevation on the inner wall of the posterior horn produced by the fibres of the forceps major of the corpus callosum as they bend backward into the occipital lobe. Synonym: bulb of posterior horn of lateral ventricle of brain. (05 Mar 2000) |