(n.) The delicate membrane by which the back part of the globe of the eye is lined, and in which the fibers of the optic nerve terminate. See Eye.
Example Sentences:
(1) The distribution of gelsolin, a calcium-dependent actin-severing and capping protein, in the retina of the developing and adult rabbit was studied.
(2) At day 7 MD occupy about 14% area of posterior retina in transverse sections in Campbell rats versus 7% in normal animals.
(3) Chromatolysis and swelling of the cell bodies of cut axons are more prolonged than after optic nerve section and resolve in more central regions of retina first.
(4) Reverse transcription of retina mRNA followed by DNA amplification using D4-specific nucleotides demonstrates the presence of D4 mRNA in retina.
(5) Electroretinographic (ERG), morphometric and biochemical studies on retinas from monkeys or rats reveal that moderate level developmental lead (Pb) exposure produces long-term selective rod deficits and degeneration.
(6) Cultured cells from fourth to ninth passage showed positive labelling for S 100 protein, carbonic anydrase (CAA), glutamine synthetase (GS), alpha cristallin (alpha C) and polyclonal glial fibrillary acidic protein (GFAP) antibody, but were negative for both monoclonal GFAP antibody and also for Muller cells in the retina.
(7) This study examines the morphology of sporadic congenital microphthalmia in 1-day-old chicks, with particular emphasis on the neural retina.
(8) We based our approach on the anteroposterior location of the incarceration site and the amount of retina incarcerated into the wound.
(9) The posterior retina remained uninvolved, and no further treatment was needed.
(10) On histopathologic examination there were microabscesses in the inner choroid and subretinal space, disrupting the outer retina but sparing the inner retina.
(11) Although the Ca2+-independent mechanism accounts for about two thirds of the total acetylcholine release in the dark, the amount of acetylcholine released in this way is small compared with the release of acetylcholine triggered by stimulation of the retina with light.
(12) These results are consistent with the idea that RPE pigment dispersion is triggered by a substance that diffuses from the retina at light onset.
(13) A specific vitamin A-dependent fluorophore was isolated from these retinas using thin-layer chromatography (TLC).
(14) Premature infants possessed 35-50% higher levels of retinal vitamin C than those found in mature retinas.
(15) The relationship of these observations to the genesis of positional markers in the regenerating retina is discussed.
(16) One may speculate whether clinical conditions exist--apart from hereditary retinal dystrophies--in which the retina becomes more sensitive to light from strong artificial or natural sources, which are otherwise innoxious.
(17) We also used an optical device to stabilize images of the real world upon the retina.
(18) The three-dimensional view obtained with scanning electron microscopy provides another perspective on the pathogenetic changes of the RCS retina.
(19) Although the chicks were behaviorally and electrophysiologically blind at the time of hatching, their retinas appeared morphologically comparable to normal chicks at this stage.
(20) These observations suggest that IDDM patients have reduced fibrinolytic activity in their retinas, which might predispose them to thromboembolic disease.
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.