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| | WHAT ARE THE MECHANISMS OF PHOTORECEPTOR ADAPTATION? |
 | | The time scale for dissociation, tens of seconds, corresponds to the period during continuous bright illumination of photoreceptors when an increase in the response recovery rate is being observed (Coles and Yamane, 1975; Cervetto et al., 1984; McCarthy and Owen, personal communication). | | | It is clear that these structures determine the basic parameters that define subsequent stages of visual information processing in the retina (cf. | | | McNaughton, P.A. (1990) Light response of vertebrate photoreceptors. |
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http://www.bbsonline.org/documents/a/00/00/04/35/bbs00000435-00/bbs.neur3.bownds.html
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| | Photoreceptor - Wikipedia, the free encyclopedia |
| | In humans, the visual system uses thousands of such photoreceptors to view, percieve, and analyze the visual world. | | | Below is the absorption spectrum for the rod and three cones found in the human retina: | | | Commonly misunderstood is the function of the photoreceptors. |
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http://en.wikipedia.org/wiki/Photoreceptor
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| | vitamin - Columbia Encyclopedia® article about vitamin |
| | One form, retinal, is a component of visual purple, a photoreceptor pigment in the retina of the eye (see vision vision, physiological sense of sight by which the form, color, size, movements, and distance of objects are perceived. | | | The human eye functions somewhat like a camera; that is, it receives and focuses light upon a photosensitive receiver, the retina. | | | Vitamin A is essential to skeletal growth, normal reproductive function, and the health of the skin and mucous membranes. |
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http://columbia.thefreedictionary.com/vitamin
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| | Nat' Academies Press, Night Vision: Current Research and Future Directions, Symposium Proceedings (1987) |
| | Some can have 20/20 vision but are legally blind due to the profound loss of their peripheral visual field with consequent "tunnel vision." Most of these disorders occur as a consequence of malfunction and loss of rod and cone photoreceptors. | | | One must keep in mind, however, that high gain alone does not guarantee optimum detection of a dim light. | | | Sensitive tests of retinal function have made it possible to diagnose these conditions in their earliest stages, sometimes many years before the patient is symptomatic or changes can be seen on routine ocular examination. |
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http://www.nap.edu/books/POD259/html/23.html
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| | Report of the Angelo Coast Range Reserve NSF Planning Workshop |
| | Our lab is investigating the roles of cytoskeletal motors in motile events critical to the morphogenesis and survival of vertebrate retinal photoreceptors, and thus to human vision. | | | Photoreceptor localization of the KIF3A and KIF3B subunits of the heterotrimeric microtubule motor kinesin II in vertebrate retina. |
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http://cbc.berkeley.edu/wkshpreport/index.html
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| | IBEA Researchers Publish Results From Environmental Shotgun Sequencing of Sargasso Sea in Science; Discover 1,800 New ... |
| | Only a few dozen photoreceptors have been characterized in microorganisms to date and less than 200 photoreceptors have been discovered from all species, including human where they are responsible for our vision. | | | Better understanding of these photoreceptor genes could be very important to IBEA researchers as they explore the mechanisms of photosynthesis as a means to efficiently and economically produce hydrogen as a fuel source. | | | One interpretation of this finding is that at least 50% of the new species discovered use some type of photobiology and could explain the diversity of species in such a low nutrient environment. |
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http://www.forrelease.com/D20040304/phth021.P2.03042004153112.21138.html
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| | Light-induced, reversible modifications of the putative photoreceptor protein of Dictyostelium discoideum amoebae |
| | The mechanism for the light perception is supposed to be based on a lens effect [5, 10]. | | | The assumption that slugs and amoebae use different photoreceptor systems for their phototaxis is not only supported by the two different action spectra but also by the fact that amoebae cannot use the lens effect because of their small size and highly variable form. | | | In the last few decades the eukaryotic cellular slime mold, Dictyostelium discoideum, has developed into a model system in which many different basic cellular processes can be studied at a molecular level. |
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http://www.photobiology.com/v1/lebert1/index.htm
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| | Photoreceptors, circadian, dynamin, multivesicular bodies, MVB, rhabdomeres, rhodopsin, lysosomes, autophagy, turnover, ... |
| | Multivesicular bodies (MVB's) were clearly seen to be merging with primary lysosomes to form secondary lysosomes for membrane breakdown. | | | Rhodopsin mutants as well as transduction mutants such as norpA (no receptor potential) were used to determine the involvement of light initiated visual excitation in photoreceptor maintenance. | | | An electron micrograph from a photoreceptor in the Drosophila compound eye showing a multivesicular body (MVB) surrounded by primary lysosomes, components of the autophagy process. |
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http://starklab.slu.edu/turnover.htm
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| | Burnside Lab, Univeristy of California Berkeley |
| | Our lab is interested in studying the photoreceptor actin cytoskeleton and understanding its contribution to the morphogenesis, maintenance, and survival of vertebrate rods and cones, and hence to vision. | | | Currently, we have focused our research on two proteins associated with the photoreceptor actin cytoskeleton, myosin 3A and fascin 2. | | | Contact Us Cone Photoreceptor of Striped Bass stained for myosin 3A (green) and Phalloidin (red). |
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http://mcb.berkeley.edu/labs/burnside
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| | CiteULike: Activation, deactivation, and adaptation in vertebrate photoreceptor cells. |
| | A quiet revolution in the study of the mechanism has occurred during the past decade with the advent of gene-targeting techniques. | | | CiteULike will not help you view an online article which you aren't authorized to view. | | | Visual transduction captures widespread interest because its G-protein signaling motif recurs throughout nature yet is uniquely accessible for study in the photoreceptor cells. |
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http://www.citeulike.org/user/morven/article/343404
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| | The Human is a Digital Mechanism. |
| | It would seem that the human nervous system is quite slow, but nature has some tricks up its sleeve also. | | | A separate nerve axon carries the signal from each photoreceptor into the brain. | | | Since we know that sight images require about 50 milliseconds, then the signals from each photoreceptor must "circulate" in the brain about 50 times before serving its complete function. |
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http://www.onelife.com/evolve/digman.html
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| | Differential Roles of CD36 and {alpha}v{beta}5 Integrin in Photoreceptor Phagocytosis by the Retinal Pigment Epithelium ... |
| | Differential Roles of CD36 and {alpha}v{beta}5 Integrin in Photoreceptor Phagocytosis by the Retinal Pigment Epithelium -- Finnemann and Silverstein 194 (9): 1289 -- The Journal of Experimental Medicine | | | The Journal of Experimental Medicine, Volume 194, Number 9, November 5, 2001 1289-1298 | | | Address correspondence to Silvia C. Finnemann, Margaret M. Dyson Vision Research Institute, Box 233 Weill Medical College of Cornell University, 1300 York Ave., New York, NY 10021. |
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http://www.jem.org/cgi/content/full/194/9/1289
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| | Photoreceptor cell - Wikipedia, the free encyclopedia |
| | The function of the photoreceptor cell is to convert the light energy into a form of energy more readily usable or functional to the organism: this conversion is called signal transduction. | | | Photoreceptor cells are found in the retina of the eye and are responsible for transducing, or converting, light into nerve signals that can be ultimately transmitted to the brain via the optic nerve. | | | The pathway for photoreceptor cells follows these basic steps: |
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http://www.wikipedia.org/wiki/Photoreceptor_cell
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| | Newswise |
| | Light regulates several physiological processes in fungi, including their ability to produce spores and the synchronization of their internal biological clocks, but their photoreceptors -- receptors that are sensitive to light and are essential for most ongoing processes -- were not known until this breakthrough discovery made by UT Southwestern researchers. | | | After 40 years of searching for the photoreceptor that controls multiple vital processes in fungi, researchers at UT Southwestern Medical Center at Dallas have discovered the protein that triggers this phenomenon. | | | July 4, 2002 -- After 40 years of searching for the photoreceptor that controls multiple vital processes in fungi, researchers at UT Southwestern Medical Center at Dallas have discovered the protein that triggers this phenomenon. |
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http://www.newswise.com/articles/2002/7/PHOTORCP.SWM.html
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| | Calcitic microlenses as part of the photoreceptor system in brittlestars : Nature |
| | Calcitic microlenses as part of the photoreceptor system in brittlestars : Nature | | | Calcitic microlenses as part of the photoreceptor system in brittlestars | | | These results provide experimental evidence that the microlenses are optical elements that guide and focus the light inside the tissue. |
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http://www.nature.com/doifinder/10.1038/35090573
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| | 01-080 (New Photoreceptor) |
| | This signal then moves along a pathway between the cells and the brain. | | | Brown researchers find new photoreceptor and visual system in the eye | | | This change triggers a cascade of biochemical reactions and an electrical response in the photoreceptor. |
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http://www.brown.edu/Administration/News_Bureau/2001-02/01-080.html
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| | Photoreceptor - definition of Photoreceptor in Encyclopedia |
| | Photoreceptor can also refer to the cells found in ommatidia and retina that contain these photosensitive pigments (see photoreceptor cell). | | | Photoreceptors are light-sensitive proteins involved in the function of photoreceptor cells. | | | Embed a dictionary search in your own web page |
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http://encyclopedia.laborlawtalk.com/Photoreceptor
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| | Photoreceptor Proteins: Smart Materials for the Electronics of the Next Millennium |
| | During the past 30 years biochemists have analysed the structure and functioning of such proteins in detail. | | | Developing technical applications making use of the opto-electrical mechanisms of these photoreceptor proteins could meet some of the increasing demands from state of the art information technology. | | | A number of other photoreceptor proteins could also have technical applications. |
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http://www.jrc.es/pages/iptsreport/vol29/english/BIO1E296.htm
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| | Botany online: Plant Responses - Light - Phototaxis |
| | This seemed to suggest that the stigma is a photoreceptor, though two observations were contrary. | | | Its action spectrum does not directly lead to the absorption spectrum of the photoreceptor, though, since part of the light is selectively absorbed by the stigma - it is also spoken of | | | In many other cases has the light to pass plastids with all their different pigments. |
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http://www.biologie.uni-hamburg.de/b-online/e30/30a.htm
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| | HHMI News: Researchers Identify Unique Circadian Rhythm Photoreceptor |
| | If there were circadian photoreceptors other than dCRY, then constant light should have produced such arrhythmia. | | | Experiments by Rosbash and his colleagues now indicate that the fly cryptochrome dCRY is perhaps the only photoreceptor molecule through which light regulates the fly's circadian rhythm, the near-universal 24-hour biological clock that governs sleep and wakefulness, rest and activity, body temperature, cardiac output, and many other functions. | | | Mammalian cryptochrome molecules appear to be involved in the central clockwork mechanism, rather than in light-detection, he said. |
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http://www.hhmi.org/news/rosbash.html
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| | Webvision: Other Plexiform Layer |
| | Therefore, the status of the signal transmitted by the ganglion cell to the brain is essentially determined by the nature of the cone bipolar contacting it which in turn is determined by its photoreceptor synapse. | | | We know that photoreceptor neurotransmitter (which is glutamate, see Dowling, 1987 and Massey, 1990, for reviews) is released in the dark in the vertebrate retina (Trifonov, 1968). | | | Hyperpolarizing (basal junction contacting) bipolar cells are the start of OFF-center channels and the depolarizing (invaginating, ribbon-related) bipolar types are the start of ON-center channels through the whole retina and visual system. |
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http://webvision.med.utah.edu/OPL2.html
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| | photoreceptor cell - definition of photoreceptor cell in the Medical dictionary - by the Free Online Medical ... |
| | This information should not be considered complete, up to date, and is not intended to be used in place of a visit, consultation, or advice of a legal, medical, or any other professional. | | | photoreceptor cell - definition of photoreceptor cell in the Medical dictionary - by the Free Online Medical Dictionary, Thesaurus and Encyclopedia. | | | Any of the rod cells present in the retina of the eye. |
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http://medical-dictionary.thefreedictionary.com/photoreceptor%20cell
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| | Kyocera Products Imaging devices Amorphous Sillicon Photoreceptor Drum |
| | Amorphous silicon (a-Si) photoreceptor drum has changed the idea about a photoreceptor; from a consumable component to a long life unit having a service life equivalent to that of the machine in which it is used. | | | In this way, the Kyocera a-Si drum makes important contributions towards the development and manufacture of environmentally friendly products. | | | The result is non-cartridge design that provides for toner replenishment without replacing the entire unit. |
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http://global.kyocera.com/prdct/ios/prd
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