| RLC | residual lung capacity |
|---|---|
| RLO | residual lymphatic output |
| ROC | receiver operating characteristic; receptor-operated channels; relative operating characteristic; re... |
| RRF | residual renal function |
| RU | radioulnar; rat unit; reading unit; residual urine; resin uptake; resistance unit; retrograde urogra... |
| reticular nucleus of thalamus | A sheet of fairly large neurons covering the lateral, ventral, and rostral surfaces of the thalamus; its reticular appearance is caused by the numerous fascicles of the thalamic peduncles which traverse the nucleus The nucleus receives numerous fibres from the cerebral cortex but it has no cortical projection. Synonym: nucleus reticularis thalami. (05 Mar 2000) |
|---|---|
| ceruleus nucleus | A widely used term designating the locus ceruleus. See: locus ceruleus. (05 Mar 2000) |
| gonad nucleus | <cell biology> The smaller nucleus in ciliate protozoans, fully active in inheritance and passed after meiosis to conjugating pairs. Gives rise to the macronucleus or macronuclei. Genes in the micronucleus are not actively transcribed. (18 Nov 1997) |
| gracile nucleus | The medial one of the three nuclei of the dorsal column, the remaining two being the cuneate nucleus and the accessory cuneate nucleus, which corresponds to the clava; it receives dorsal-root fibres conveying sensory innervation of the leg, and lower trunk, and projects, by way of the medial lemniscus, to the ventral nucleus posterior nucleus of the thalamus. Synonym: nucleus gracilis, nucleus fasciculi gracilis, nucleus funiculi gracilis, nucleus of Goll. (05 Mar 2000) |
| mesencephalic nucleus of trigeminal nerve | <anatomy, nerve> A long, narrow plate of unipolar neurons extending throughout the length of the midbrain, in and along the lateral angle of the central gray substance. The nucleus is the single known instance of primary sensory neurons enclosed in the central nervous system instead of in a peripheral sensory ganglion. Its peripheral axonal processes pass with the trigeminal nerve, give collaterals to the trigeminal motor nucleus, and terminate in the muscles of mastication. Synonym: nucleus tractus mesencephali nervi trigemini. (05 Mar 2000) |
| rhombencephalic gustatory nucleus | The rostral one-third of the nucleus of solitary tract, receiving afferents from the facial, glossopharyngeal, and vagus nerves conveying impulses originating from the receptor cells of the taste buds. (05 Mar 2000) |
| Perlia's nucleus | A small cell group located between the somatic cell columns of the oculomotor nuclei. Since it is placed between the groups of motor neurons innervating, respectively, the left and right medial rectus muscles, the nucleus is considered to possibly represent an integrating mechanism for ocular convergence. Synonym: convergence nucleus of Perlia, Spitzka's nucleus. (05 Mar 2000) |
| gustatory nucleus | See: rhombencephalic gustatory nucleus, thalamic gustatory nucleus. (05 Mar 2000) |
| Roller's nucleus | Lateral nucleus of the accessory nerve, a small bulbar nucleus lying immediately anterior to the hypoglossal nucleus, considered one of the perihypoglossal nuclei. (05 Mar 2000) |
| roof 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) |
| phenanthrene nucleus | Misnomer for tetracyclic steroid nucleus. (05 Mar 2000) |
| Clarke's nucleus | A column of large neurons located in the base of the posterior gray column of the spinal cord, extending from the first thoracic through the second lumbar segment; it gives rise to the dorsal spinocerebellar tract of the same side. Synonym: nucleus thoracicus, Clarke's column, Clarke's nucleus, dorsal nucleus, nucleus dorsalis, Stilling's column, Stilling's nucleus. (05 Mar 2000) |
| phrenic nucleus | A nucleus comprised of motor neurons located in medial areas of the ventral horn of the spinal cord from about C3 to C6; axons of neurons in this nucleus innervate the diaphragm. (05 Mar 2000) |
| cochlear nucleus | The brainstem nucleus that receives the central input from the cochlear nerve. The cochlear nucleus is located lateral and dorsolateral to the inferior cerebellar peduncles and is functionally divided into dorsal and ventral parts. It is tonotopically organised, performs the first stage of central auditory processing, and projects (directly or indirectly) to higher auditory areas including the superior olivary nuclei, the medial geniculi, the inferior colliculi, and the auditory cortex. (12 Dec 1998) |
| Monakow's 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) |