| OLB | olfactory bulb; open liver biopsy; open lung biopsy |
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| olf | olfactory |
| OLFR | olfactory receptor |
| OMP | olfactory marker protein; ornithine monophosphate; outer membrane protein |
| OP | occipitoparietal; occipitoposterior; occiput posterior; octapeptide; olfactory peduncle; opening pre... |
| olfactory sulcus of nasal cavity | The narrow groove in the nasal cavity above the agger nasi that leads from the atrium to the olfactory area. Synonym: sulcus olfactorius cavum nasi. (05 Mar 2000) |
|---|---|
| olfactory tract | A nervelike, white band composed primarily of nerve fibres originating from the mitral cells and tufted cells of the olfactory bulb but also containing the scattered cells of the anterior olfactory nucleus. The tract is closely applied to the ventral surface of the frontal lobe, and attaches itself to the base of the cerebral hemisphere at the olfactory trigone, beyond which it extends in the form of the olfactory striae which distribute their fibres to the olfactory tubercle and, in largest number, to the olfactory cortex on and around the uncus of the parahippocampal gyrus. See: olfactory nerves. Synonym: tractus olfactorius, olfactory peduncle. (05 Mar 2000) |
| olfactory trigone | A grayish triangular area corresponding to the attachment of the olfactory peduncle ("olfactory nerve" or olfactory tract) to the base of the brain, at the anterior border of the anterior perforated substance. Synonym: trigonum olfactorium. (05 Mar 2000) |
| olfactory tubercle | A small, oval area at the base of the cerebral hemisphere, between the diverging medial and lateral olfactory striae, in the anteromedial part of the anterior perforated substance; it is formed by a small area of allocortex characterised by the presence of the islands of Calleja. Corresponding to a much more prominent structure in nonprimate mammals (especially rodents and insectivores), the olfactory tubercle receives fibres from the olfactory bulb by way of the intermediate olfactory stria; it has efferent connections with the hypothalamus and the mediodorsal nucleus of the thalamus. Synonym: tuberculum olfactorium. (05 Mar 2000) |
| annectent gyrus | A small convolution connecting two lobes or two main gyri in the depth of a sulcus. Synonym: annectent gyrus, transitional convolution. (05 Mar 2000) |
| anterior central gyrus | Bounded posteriorly by the central sulcus and anteriorly by the precentral sulcus. Synonym: gyrus precentralis, anterior central convolution, anterior central gyrus, ascending frontal convolution, ascending frontal gyrus. (05 Mar 2000) |
| anterior piriform gyrus | A gyrus covering deeply placed amygdaloid nucleus; concerned with olfactory function. Synonym: anterior piriform gyrus. (05 Mar 2000) |
| artery of angular gyrus | The last branch of the terminal part of the middle cerebral artery distributed to parts of the temporal parietal and occipital lobes. Synonym: arteria gyri angularis, angular artery. (05 Mar 2000) |
| ascending frontal gyrus | Bounded posteriorly by the central sulcus and anteriorly by the precentral sulcus. Synonym: gyrus precentralis, anterior central convolution, anterior central gyrus, ascending frontal convolution, ascending frontal gyrus. (05 Mar 2000) |
| ascending parietal gyrus | The anterior convolution of the parietal lobe, bounded in front by the central sulcus (fissure of Rolando) and posteriorly by the interparietal sulcus. Synonym: gyrus postcentralis, ascending parietal convolution, ascending parietal gyrus, posterior central convolution, posterior central gyrus. (05 Mar 2000) |
| callosal gyrus | cingulate gyrus |
| parahippocampal gyrus | A long convolution on the medial surface of the temporal lobe, forming the lower part of the fornicate gyrus, extending from behind the splenium corporis callosi forward along the dentate gyrus of the hippocampus from which it is demarcated by the hippocampal fissure. The anterior extreme of the gyrus curves back upon itself, forming the uncus, the major location of the olfactory cortex. See: entorhinal area. Synonym: gyrus parahippocampalis, hippocampal convolution, hippocampal gyrus. (05 Mar 2000) |
| marginal gyrus | A broad convolution running in an anteroposterior direction on the medial edge of the convex surface and of each frontal lobe. Synonym: gyrus frontalis superior, marginal gyrus, superior frontal convolution. (05 Mar 2000) |
| paraterminal gyrus | A slender vertical whitish band immediately anterior to the lamina terminalis and anterior commissure; contrary to its name, it is not a cortical convolution but is the ventral continuation of the transparent septum. Synonym: area subcallosa, gyrus paraterminalis, gyrus subcallosus, pedunculus corporis callosi, corpus paraterminale, paraterminal body, paraterminal gyrus, peduncle of corpus callosum, precommissural septal area, subcallosal area, Zuckerkandl's convolution. (05 Mar 2000) |
| medial occipitotemporal gyrus | A relatively short horizontal convolution on the inferomedial aspect of the occipital and temporal lobes, demarcated from the lateral occipitotemporal or fusiform gyrus by the deep collateral sulcus, from the cuneus by the calcarine sulcus; its anterior extreme abuts the isthmus of the parahippocampal gyrus; the medial or upper strip of the gyrus forming the lower bank of the calcarine sulcus corresponds to the inferior half of the striate area or primary visual cortex and represents the contralateral upper quadrant of the binocular field of vision. Synonym: gyrus lingualis, gyrus occipitotemporalis medialis, medial occipitotemporal gyrus. (05 Mar 2000) |