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CreatorTitleDescriptionSubjectDate
1 Normann, Richard A.Background and bleaching adaptation in luminosity type horizontal cells in the isolated turtle retina1. The effects of background illumination and bleached photopigment on luminosity type horizontal cells were studied in the isolated turtle retina. 2. Background illumination, which produced less than 60% bleaching, hyperpolarized and desensitized the horizontal cells to a degree which depended upon...Turtles; Retina; Photoreceptors; Bleached photopigment; Dark Adaptation1990
2 Normann, Richard A.Effects of background illumination on the photoresponses of red and green cones1. The photoresponses of light- and dark-adapted red and green cone photoreceptors were recorded intracellularly in the retina of the turtle, Pseduemys scripta elegans. Background illumination produced similar effects on both types of cones. 2. In response to the onset of a prolonged, steady backgro...Turtles; Adaptation, Ocular; Retina; Signal Transmission1979
3 Normann, Richard A.; Chandler, John P.Effects of calcium ions on L-type horizontal cells in the isolated turtle retinaA technique by which the retina can be isolated from the turtle eye is described. Scanning electron microscopy revealed morphological variability between preparations and also between regions of the same one. Large areas were often totally free of any pigment epithelial cells, yet contained a high p...Retina; Calcium; Horizontal Cell; Turtle1990
4 Normann, Richard A.Effects of GABA and related drugs on horizontal cells in the isolated turtle retinaThe role of GABA in the outer plexiform layer of the turtle retina has been examined by intracellular recordings from L- and C-type horizontal cells in the isolated retina preparation. GABA (1-5 mM) slightly depolarized the L-type horizontal cells, reduced the amplitude of their photoresponses, and ...Retina; Horizontal Cells; Synapse; Negative Feedback; GABA; Turtle1990
5 Angelucci, AlessandraExperimentally induced retinal projections to the ferret auditory thalamus: development of clustered eye-specific patterns in a novel targetWe have examined the relative role of afferents and targets in pattern formation using a novel preparation, in which retinal projections in ferrets are induced to innervate the medial geniculate nucleus (MGN). We find that retinal projections to the MGN are arranged in scattered clusters. Clusters a...Retina; Ferrets1997
6 Fuhrmann, Sabine; Zhang, Jianmin; Vetter, Monica L.Investigation of Frizzled-5 during embryonic neural development in mouseCellular and tissue--tissue interactions regulate development of the central nervous system (CNS) and a paramount question is what is the nature of the signals involved in these interactions. The vertebrate eye represents an excellent and challenging CNS model because it contains multiple cell and ...Mouse; Eye; Optic cup; Morphogenesis; Retina; Lens; Wnt; Frizzled; Pituitary2008
7 Normann, Richard A.Oscillations in rod and horizontal cell membrane potential: evidence for feed-back to rods in the vertebrate retina1. Rods and horizontal cells were studied with intracellular recordings in the retina of the toad, Bufo marinus; 161 cells were from the eyecup preparation and thirty were from the isolated perfused retina. 2. Of these cells, 39% exhibited either transient or sustained oscillations of membrane poten...Retina; Photoreceptors; Toads; Adaptation, Ocular1976
8 Creel, Donnell J.; Leventhal, Audie G.Retinal projections in tyrosinase-negative albino catsRetinal projections were examined in two tyrosinase-negative albino cats using autoradiographic techniques. Cats from this colony have pink eyes; their retinal pigment epithelium, ciliary body, and iris epithelium are completely devoid of melanin pigment. Test breeding for five generations indicates...Cats; Albinism; Vision; Autoradiography; Retina1982-07
9 Normann, Richard A.Signal transmission from red cones to horizontal cells in the turtle retina1. Intracellular recordings were made from L-type horizontal cells in the retina of the turtle Pseudemys scripta elegans. The responses were evoked by 500 msec pulses of 'white' light. 2. L-type horizontal cells were classified as either, 'small receptive field' s.r.f. or 'large receptive field' l.r...Turtles; Synapses; Retina; Photoreceptors1979
10 Levine, Edward M.Sonic hedgehog promotes rod photoreceptor differentiation in mammalian retinal cells in vitro.The hedgehog gene family encodes secreted proteins important in many developmental patterning events in both vertebrates and invertebrates. In the Drosophila eye disk, hedgehog controls the progression of photoreceptor differentiation in the morphogenetic furrow. To investigate whether hedgehog prot...Sonic hedgehog; Indian hedgehog; Desert hedgehog; Retina; Mitogenesis; Differentiation; Rod Photoreceptor1997-08-15
11 Normann, Richard A.; Johansson,Torbjorn; Abbasi, Masoud; Huber, Robert J.Three-dimensional architecture for a parallel processing photosensing arrayA three-dimensional architecture for a photosensing array has been developed. This silicon based architecture consists of a 10 x 10 array of photosensors with 80 microns diameter, through chip interconnects to the back side of a 500 microns thick silicon wafer. Each photosensor consists of a 300 x 3...Retina; Optics; Silicon; Photosensing1992
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