retina | Light sensitive layer of the eye. In vertebrates, looking from outside, there are four major cell layers: (i) the outer neural retina, which contains neurons (ganglion cells, amacrine cells, bipolar cells) as well as blood vessels, (ii) the photoreceptor layer, a single layer of rods and cones, (iii) the pigmented retinal epithelium (PRE or RPE), (iv) the choroid, composed of connective tissue, fibroblasts and including a well vascularised layer, the chorio capillaris, underlying the basal lamina of the PRE. Behind the choroid is the sclera, a thick organ capsule. In molluscs (especially cephalopods such as the squid) the retina has the light sensitive cells as the outer layer with the neural and supporting tissues below. See: retinal rods, retinal cones, rhodopsin. (18 Nov 1997) |
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retina-specific amine oxidase | <enzyme> Genbank d88213 Registry number: EC 1.4.- Synonym: rao enzyme, human (26 Jun 1999) |
retinacula musculorum fibularium | An alternate term for peroneal retinaculum, peroneal retinaculum. (05 Mar 2000) |
retinacula musculorum peroneorum | Superior and inferior fibrous bands retaining the tendons of the peroneus longus and brevis in position as they cross the lateral side of the ankle. Synonym: retinacula musculorum peroneorum, retinacula musculorum fibularium, retinacula of peroneal muscles. (05 Mar 2000) |
retinacula of extensor muscles | See: inferior extensor retinaculum, superior extensor retinaculum. (05 Mar 2000) |
retinacula of nail | Fibrous attachments of the nail-bed to the underlying phalanx. Synonym: retinacula unguis. (05 Mar 2000) |
retinacula of peroneal muscles | Superior and inferior fibrous bands retaining the tendons of the peroneus longus and brevis in position as they cross the lateral side of the ankle. Synonym: retinacula musculorum peroneorum, retinacula musculorum fibularium, retinacula of peroneal muscles. (05 Mar 2000) |
retinacula unguis | Fibrous attachments of the nail-bed to the underlying phalanx. Synonym: retinacula unguis. (05 Mar 2000) |
retinaculum | A hook-like structure to which another structure is tethered, in orchids and members of the family Asclepiadaceae, the structure to which pollen masses are attached, in Acanthaceae, the persistent stalk of an ovule. (09 Oct 1997) |
retinaculum capsulae articularis coxae | One of several longitudinal folds of the articular capsule of the hip joint reflected onto the femoral neck deep to which the retinacular branches of the medial femoral circumflex artery pass to reach the femoral head. Synonym: retinaculum capsulae articularis coxae, Weitbrecht's fibres. (05 Mar 2000) |
retinaculum caudale | Fibrous bands, remnants of the notochord, that extend from the skin to the coccyx, forming the coccygeal foveola. Synonym: retinaculum caudale, caudal ligament, ligamentum caudale. (05 Mar 2000) |
retinaculum cutis | One of the numerous small fibrous strands that extend through the superficial fascia attaching the deep surface of the dermis to the underlying deep fascia determining the mobility of the skin over the deep structures; these are particularly well developed over the breast where they are known as suspensory ligaments of the breast; they are also well-developed, but short, in the palms and soles. Synonym: retinaculum of skin. (05 Mar 2000) |
retinaculum extensorum | A strong fibrous band formed as a thickening of the antebrachial deep fascia, stretching obliquely across the back of the wrist, attaching deeply to ridges on the dorsal aspect of the radius, triquetral and pisiform bones, binding down the extensor tendons of the fingers and thumb. Synonym: retinaculum extensorum, dorsal carpal ligament, ligamentum carpi dorsale. (05 Mar 2000) |
retinaculum flexorum | <anatomy> A strong fibrous band crossing the front of the carpus and binding down the flexor tendons of the digits and the flexor carpi radialis tendon and the median nerve; in so doing it creates the carpal tunnel. Synonym: retinaculum flexorum, deep part of flexor retinaculum, flexor retinaculum, ligamentum carpi transversum, ligamentum carpi volare, volar carpal ligament. (05 Mar 2000) |
retinaculum musculorum extensorum inferius | A Y-shaped ligament restraining the extensor tendons of the foot distal to the ankle joint. Synonym: retinaculum musculorum extensorum inferius, cruciate ligament of leg, inferior retinaculum of extensor muscles, ligamentum cruciatum cruris. (05 Mar 2000) |
ganglion cells of retina | The nerve cell's of the retina whose central processes (fibres) form the optic nerve; their peripheral processes synapse with the bipolar cell's and through them with the rod and cone cell's; these cell bodies are round or flask-shaped and vary considerably in size. (05 Mar 2000) |
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ganglionic layer of retina | The intermediate layer of neurons in the retina composed largely of bipolar cells. Synonym: internal nuclear layer of retina, stratum ganglionare retinae, stratum nucleare internum retinae. (05 Mar 2000) |
medial arteriole of retina | An arteriole supplying the part of the retina between the optic disk and the macula. Synonym: arteriola medialis retinae. (05 Mar 2000) |
medial venule of retina | The small vein that passes from the part of the retina between the macula and the optic disk to join the central vein. Synonym: venula medialis retinae. (05 Mar 2000) |
central artery of retina | A branch of the ophthalmic artery which penetrates the optic nerve 1 cm behind the eye to enter the eye at the optic papilla in the retina; it divides into superior and inferior temporal and nasal branches. Synonym: arteria centralis retinae, arteria retinae centralis, Zinn's artery. (05 Mar 2000) |
central vein of retina | Formed by union of the retinal veins and accompanies the artery of the same name in the optic nerve. Synonym: vena centralis retinae. (05 Mar 2000) |
cerebral layer of retina | The internal layer of the retina containing the neural elements, as distinguished from the outer leaf of the retina, or pigmented layer. Synonym: pars optica retinae, neural layer of retina, optic part of retina, stratum cerebrale retinae. (05 Mar 2000) |
granular layers of retina | The outer nuclear layer, layer 4, of the retina, neuroepithelial layer of retina, and the inner layer, layer 6, of the retina, ganglionic layer of retina. Synonym: granular layers of retina, stratum nucleare externum et internum retinae. (05 Mar 2000) |
rivalry of retina | Simultaneous excitation of corresponding retinal areas of each eye by stimuli that differ in size, colour, shape, or luminance, making fusion impossible. (05 Mar 2000) |
rod cell of retina | 1. A straight and slender stick; a wand; hence, any slender bar, as of wood or metal (applied to various purposes). Specifically: An instrument of punishment or correction; figuratively, chastisement. "He that spareth his rod hateth his son." (Prov. Xiii. 24) A kind of sceptor, or badge of office; hence, figuratively, power; authority; tyranny; oppression. "The rod, and bird of peace." . A support for a fishing line; a fish pole. <machinery> A member used in tension, as for sustaining a suspended weight, or in tension and compression, as for transmitting reciprocating motion, etc.; a connecting bar. An instrument for measuring. 2. A measure of length containing sixteen and a half feet; called also perch, and pole. Black rod. <anatomy> Rods and cones, the elongated cells or elements of the sensory layer of the retina, some of which are cylindrical, others somewhat conical. Origin: The same word as rood. See Rood. Source: Websters Dictionary (01 Mar 1998) |
rods (retina) | One of the two photoreceptor cell types of the vertebrate retina. In rods the photopigment is in stacks of membranous disks separate from the outer cell membrane. Rods are more sensitive to light than cones, but rod mediated vision has less spatial and temporal resolution than cone vision. (12 Dec 1998) |
gyrate atrophy of choroid and retina | A slowly progressive atrophy of the choriocapillaris, pigmentary epithelium, and sensory retina, with irregular confluent atrophic areas and an associated ornithinuria; autosomal recessive inheritance; due to a deficiency of ornithine d-aminotransferase. (05 Mar 2000) |
ciliary part of retina | ciliary part of retina |
coarctate retina | An obsolete term for a ringlike effusion of fluid between the choroid and retina, giving the latter a funnel shape. (05 Mar 2000) |
molecular layer of retina | Name applied to each of the plexiform layers of the retina. Synonym: stratum moleculare retinae. (05 Mar 2000) |