| RAS | rapid atrial stimulation; recurrent aphthous stomatitis; reflex activating stimulus; reliability, av... |
|---|---|
| REM | rapid eye movement; recent-event memory; reticular erythematous mucinosis; return electrode monitor;... |
| RET | reticular; reticulocyte; retina; retention; retained; right esotropia |
| RF | radial fiber; radio frequency; receptive field; regurgitant fraction; Reitland-Franklin [unit]; rela... |
| RL | radial line; radiation laboratory; reduction level; renal dysplasia-limb defects [syndrome]; resisti... |
| retinal dysplasia | <ophthalmology> Congenital, often bilateral, retinal abnormality characterised by the arrangement of outer nuclear retinal cells in a palisading or radiating pattern surrounding a central ocular space. This disorder is sometimes hereditary. (12 Dec 1998) |
|---|---|
| retinal embolism | Embolism of an artery of the retina. (05 Mar 2000) |
| retinal fold | A congenital or secondary fold, consequent to membrane contraction, producing star-shaped, meridional, or circular fold's on the retina. (05 Mar 2000) |
| retinal ganglion cell | <pathology> A type of interneuron that conveys information from the retinal bipolar, horizontal and amacrine cells to the brain. (18 Nov 1997) |
| retinal ganglion cells | Cells of the innermost nuclear layer of the retina, the ganglion cell layer, which project axons through the optic nerve to the brain. They are quite variable in size and in the shapes of their dendritic arbors, which are generally confined to the inner plexiform layer. (12 Dec 1998) |
| retinal image | A real image formed on the retina. (05 Mar 2000) |
| retinal isomerase | <enzyme> Converts all-trans-retinal to 11-cis-retinal Registry number: EC 5.2.1.3 Synonym: retinal photoisomerase (26 Jun 1999) |
| retinal monooxygenase | <enzyme> Cytochrome p-450 and NADPH-dependent enzyme from rabbit liver microsomes Registry number: EC 1.14.13.- Synonym: retinoic acid synthase (26 Jun 1999) |
| retinal necrosis syndrome, acute | <ophthalmology> Mild to fulminant necrotizing vaso-occlusive retinitis associated with a high incidence of retinal detachment and poor vision outcome. (12 Dec 1998) |
| retinal neovascularization | <ophthalmology> New blood vessels originating from the retinal veins and extending along the inner (vitreal) surface of the retina. This process is characterised by a diseased retina with a disturbed vascular bed. Neovascularization is associated with a variety of conditions including vascular occlusion, sickle cell diseases, sarcoidosis. (12 Dec 1998) |
| retinal perforation | <ophthalmology> Perforations through the whole thickness of the retina including the macula as the result of inflammation, trauma, degeneration, etc. The concept includes retinal breaks, tears, dialyses, and holes. (12 Dec 1998) |
| retinal pigmented epithelial cell | See: pigmented retinal epithelium, retina. (18 Nov 1997) |
| retinal pigments | <ophthalmology, physiology> Chemicals functioning in the visual cycle in retinal rod cells. Through excitation by visible light, a series of complex molecular changes occur that serve to trigger in the optical nerve endings an impulse transmitted to the brain, resulting in the perception of vision. (12 Dec 1998) |
| retinal reductase | Alcohol dehydrogenase (NAD(P)+). (05 Mar 2000) |
| retinal rod | <ophthalmology, physiology> Major photoreceptor cell of vertebrate retina (about 125 million in a human eye). Columnar cells (about 40m long, 1m diameter) having three distinct regions: a region adjacent to and synapsed with, the neural layer of the retina contains the nucleus and other cytoplasmic organelles, below this is the inner segment, rich in mitochondria, that is connected through a thin neck (in which is located a ciliary body) to the outer segment. The outer segment largely consists of a stack of discs membrane infoldings that are incompletely separated in cones) that are continually replenished near the inner segment and that are shed from the distal end and phagocytosed by the pigmented epithelium. The membranes of the discs are rich in rhodopsin, the pigment that absorbs light. (03 Jul 1999) |