(1) Following central retinal artery ligation, infarction of the retinal ganglion cells was reflected by a 97 per cent reduction in the radioactively labeled protein within the optic nerve.
(2) In 22 cases (63%), retinal detachment was at least partially flattened in the area of the posterior pole of the eye.
(3) When the eye was dissected into anterior uveal, scleral, and retinal complexes, prostaglandin D2 was formed in the highest degree in all the complexes, whereas prostaglandin E2 and F2 alpha formation was specific to given ocular regions.
(4) Because of the short detachment interval, and the absence of underlying pathology or trauma, the recovery process described here probably represents an example of optimum recovery after retinal reattachment.
(5) The number of axons displaying peptide-like immunoreactivity within the optic nerve, retinal or cerebral to the crush, and within the optic chiasm gradually decreased after 2-3 months.
(6) Once the normal variations are mastered, appreciation of retinal, choroidal, optic nerve, and vitreal abnormalities is possible.
(7) In 60 rhesus monkeys with experimental renovascular malignant arterial hypertension (25 one-kidney and 35 two-kidney model animals), we studied the so-called 'hard exudates' or white retinal deposits in detail (by ophthalmoscopy, and stereoscopic color fundus photography and fluorescein fundus angiography, on long-term follow-up).
(8) It is proposed that microoscillations of the eye increase the threshold for detection of retinal target displacements, leading to less efficient lateral sway stabilization than expected, and that the threshold for detection of self motion in the A-P direction is lower than the threshold for object motion detection used in the calculations, leading to more efficient stabilization of A-P sway.
(9) Two lectins, wheat germ agglutinin (WGA) and peanut agglutinin (PNA), were used to compare domains within the interphotoreceptor matrices (IPM) of the cat and monkey, two species where the morphological relationship between the retinal pigment epithelium (RPE) and photoreceptors is distinctly different.
(10) A patient with a history of hypertension had a combined central retinal artery and vein occlusion in one eye.
(11) Certain underlying factors in several types of retinal degeneration are first discussed, followed by characteristics of diabetic maculopathy and of other types of macular degeneration including that due to aging.
(12) A total of 27 reoperations including eight repeat PRs (5 of which were successful) was required to achieve permanent retinal reattachment.
(13) The observations support the idea that the function of pericytes in the choriocapillaris, the major source of nutrition for the retinal photoreceptors, resides in their contractility, and that pericytes do not remove necrotic endothelium during capillary atrophy.
(14) The death of retinal ganglion cells during development thus seems to serve 2 purposes: It provides for the quantitative matching of the ganglion cell population to the needs of its central projection fields, and, at the same time, it serves to selectively eliminate those cells whose axons project to inappropriate targets or to inappropriate regions within the correct target fields.
(15) Changes in protein phosphorylation induced by phagocytic challenge were identified in cultured rat retinal pigment epithelium (RPE) following exposure to isolated rat rod outer segments (ROS) or to polystyrene latex microspheres (PSL).
(16) The chromophore of octopus rhodopsin is 11-cis retinal, linked via a protonated Schiff base to the protein backbone.
(17) After intravenous or dorsal lymph sac injections of 3H-22:6, most of the retinal label was seen in rod photoreceptor cells.
(18) This suggests that many retinal ganglion cells continue to discharge in total darkness for long periods.
(19) The yield of such studies may be high for an understanding of such diseases as myopia, retinal detachment, and keratoconus.
(20) Twenty patients with central retinal vein occlusion were randomly divided into two groups in a prospective study to evaluate the effects of xenon are photocoagulation in central retinal vein occlusion.
Rhodopsin
Definition:
(n.) The visual purple. See under Visual.
Example Sentences:
(1) The chromophore of octopus rhodopsin is 11-cis retinal, linked via a protonated Schiff base to the protein backbone.
(2) Consistent with this result, the mutant Trp-265----Phe showed no detectable light-dependent activation of transducin or phosphorylation by rhodopsin kinase.
(3) The agreement can be improved by calculating with a conformative coupling between two rhodopsin molecules.
(4) The overall results strongly suggest that light induces conformational changes not only in the C-terminal end but also in the second and the third extradiscal loop of rhodopsin.
(5) Two members of another family with autosomal dominant retinitis pigmentosa showed a guanine-to-thymine mutation in the first nucleotide of codon 190 in the rhodopsin gene that resulted in an aspartate-to-tyrosine change.
(6) Meta II is the form of photolyzed rhodopsin which binds and activates the visual G-protein (Gt); thus, its relative abundance at equilibrium and temporal stability are important parameters in determining the efficiency of visual signal transduction.
(7) We have investigated the relationship between rhodopsin photochemical function and the retinal rod outer segment (ROS) disk membrane lipid composition using flash photolysis techniques.
(8) These results localize the light-stimulated phospholipase C activity to the distal segments and suggest that a G-protein couples rhodopsin to phospholipase C.
(9) It was previously shown that this monoclonal antibody, mAb 4A, blocks interactions with rhodopsin and its epitope was located within the region Arg310-Phe350 at the COOH terminus of the alpha t subunit.
(10) The first photoproduct in the photolysis of rhodopsin was lumirhodopsin.
(11) The photopigments, rhodopsin and retinochrome, have been localized in cephalopod retinae using light and electron microscopic immunocytochemical methods.
(12) Several other G proteins of known functions have been purified: Gi, which couples inhibitory receptors to adenylate cyclase, and transducin which couples photoexcited rhodopsin to cyclic GMP phosphodiesterase.
(13) Retinol isomerase is concentrated in the pigment epithelium; this localization clarifies the role of this tissue in rhodopsin regeneration and explains the need to transfer all-trans retinol from the rod outer segments to the pigment epithelium during the visual cycle.
(14) The slow PIII response reflected mainly rod activity in its time course and spectral response curve, and the ratio of the peak amplitude of the fast PIII response to the slow one remained almost constant within a scotopic range when rhodopsin was kept at a constant concentration.
(15) It is found that substitution of one SH hydrogen at the G alpha-subunit by N-ethylmaleimide or thionitrobenzoate still allows dark binding of the G-unit to the membrane but blocks its light binding to rhodopsin.
(16) The horizontal streak of high rhodopsin levels is preferentially reduced in this retinopathy.
(17) We studied the ocular findings in eight unrelated patients with a form of autosomal dominant retinitis pigmentosa and the same cytosine-to-thymine transition in the second nucleotide of codon 347 of the rhodopsin gene.
(18) The quality of the micrographs, immunocytochemical labelling of rhodopsin and phosphodiesterase, and cyclic nucleotide analyses were similar to those obtained with retinas from freshly enucleated eyes.
(19) In order to prepare a completely light-stable rhodopsin, we have synthesized an analog, II, of 11-cis retinal in which isomerization at the C11-C12 cis-double bond is blocked by formation of a cyclohexene ring from the C10 to C13-methyl.
(20) Fourier-transform infrared difference spectroscopy has been used to detect the vibrational modes in the chromophore and protein that change in position or intensity between rhodopsin and the photoproducts formed at low temperature (70 K), bathorhodopsin and isorhodopsin.