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DictionarySeefiberMuller fibers
Mül·ler fi·bers (mul'ĕr), 1. Synonym(s): circular fibers2. sustentacular neuroglial cells of the retina, running through the thickness of the retina from the internal limiting membrane to the bases of the rods and cones where they form a row of junctional complexes. Synonym(s): Müller radial cells, sustentacular fibers of retinafiber (fi'ber) [L. fibra, filament, fiber] 1. A threadlike or filmlike structure, e.g., a nerve fiber.2. A neuron or its axonal portion. 3. An elongated threadlike structure. It may be cellular as nerve fiber or muscle fiber, or may be a cellular product, as collagen, elastic, oxytalan, or reticular fiber. 4. A slender cellulosic structure derived from plants such as cotton. See: rayon, purifiedA fiberA heavily myelinated, fast-conducting nerve fiber. accelerator fiberA sympathetic nerve fiber that carries impulses to increase heart rate.afferent fiberA nerve fiber that carries sensory impulses to the central nervous system from receptors in the periphery. cholinergic fiberAny preganglionic fiber, postganglionic parasympathetic fiber, postganglionic sympathetic fiber to a sweat gland, or efferent fiber to skeletal muscle.circular fibersCollagen bundles in the gingiva that surround a tooth.climbing fiberAn excitatory axon from the inferior olivary nucleus that synapses with dendrites of Purkinje cells in the cerebellar cortexdepressor fiberA nerve that decreases arterial muscle tone and, as a result, lowers blood pressure.dietary fiberThe components of food that resist chemical digestion, including cellulose, hemicellulose, lignin, gums, mucilages, and pectin. Dietary fibers are classified according to their solubility in water. Water-insoluble fibers include cellulose, lignin, and some hemicelluloses. These substances can soften and increase the bulk of the bowel movement. Natural gel-forming fibers found in fruits and vegetables such as gums, mucilages, and some hemicelluloses are water soluble. Most foods of plant origin contain both soluble and insoluble dietary fiber. Many disease processes including constipation, diabetes mellitus, gallstones, hemorrhoids, high blood pressure, irritable bowel syndrome, and obesity have been shown to be ameliorated by a high-fiber diet. There are epidemiological data supporting the existence of an inverse relationship between the disease and dietary fiber consumption. The relation between fiber intake and colorectal cancer is complex; some studies suggest that fiber intake is protective, while others suggest that it is not. Foods rich in fiber include whole-grain foods, bran flakes, beans, fruits, leafy vegetables, nuts, root vegetables and their skins. efferent fiberA nerve fiber that carries motor impulses from the central nervous system to effector organs.extrafusal fibersThe muscle fibers surrounding a muscle spindle. fermentable fiberSoluble fiber.gingival fibersCollagen fibers that support the marginal or interdental gingiva and are adapted to the tooth surface.inhibitory fiberA nerve fiber that carries impulses to decrease heart rate.insoluble fiberAny dietary fiber that does not dissolve in water. Insoluble dietary fiber includes hemicellulose, cellulose, and lignin. An example is wheat bran. intercolumnar fiberAn intercrural fiber, part of the superficial inguinal ring.interradicular fibersThe collagen fibers of the periodontal ligament in the interradicular area, attaching the tooth to alveolar bone. intrafusal muscle fiberThe structural component of the muscle spindle, made up of small skeletal muscle fibers at either end and a central noncontracile region where the sensory receptors are located. James fibers See: James fibersMahaim fibers See: Mahaim fibersman-made fiberA synthetic fiber made from chemicals (e.g., rayon or polyester). Synonym: synthetic fibermedullated fiberAn obsolete term for a myelinated neuron. Müller fibers See: Müller, Heinrichmossy fiberAn excitatory axon from outside the cerebellum that synapses in the granular layer of the cerebellar cortex. Mossy fiber terminals are the central elements in complex synaptic formations that include dendrites of granular neurons and neurites of Golgi cells. motor fiberAny of the axons of motor neurons that innervate skeletal muscles.muscle fiberA muscle cell in striated, smooth, or cardiac muscle. myelinated fiberA nerve fiber whose axon (dendrite) is wrapped in a myelin sheath.nerve fiber See: nerve fibernigrostriatal fibersNigrostriate bundle.nonmedullated fiberUnmyelinated fiber.oxytalan fibersBundles of thin, acid-resistant fibrils found in the periodontium.preganglionic fiberThe axon of a preganglionic neuron. principal fibersThe major fiber groups of the functioning periodontium. They attach the tooth to the bone and adjacent teeth. propriospinal fibersAxons that connect regions of the spinal cord. Purkinje fiber See: Purkinje, Johannes E. vonreticular fiberAny of the extremely fine argyrophilic (silver-staining) fibers found in reticular tissue.secretory fiberA peripheral motor nerve fiber that innervates glands and stimulates secretion.Sharpey's fibers See: Sharpey, WilliamSharpey's perforating fibers See: Sharpey, Williamsoluble fiberAny dietary fiber that dissolves in water. Soluble fiber is metabolized by bacteria in the gastrointestinal tract into short chain fatty acids, which in turn nourish commensal bacteria in the gut. Examples include most fruit and vegetable fibers, e.g., pectins, barley, cereal grains, cornmeal, and oats. See: fermentable fibersynthetic fiberMan-made fiber.transseptal fiberAny of the collagenous fibers that extend between the teeth and are embedded in the cementum of adjacent teeth. unmyelinated fiberA nerve fiber that lacks a myelin sheath, although a neurilemma may be present in the peripheral nervous system. zonular fiberAny of the interlacing fibers of the zonula ciliaris. Müller, Heinrich, German anatomist, 1820-1864. Müller fibers - (1) circular fibers - (2) sustentacular neuroglial cells of the retina. Synonym(s): Müller radial cellsMüller muscle - Synonym(s): circular fibers; orbitalis muscle; superior tarsal muscleMüller radial cells - Synonym(s): Müller fibers (2)Müller trigone - the floor of the supraoptic recess of the third ventricle.FinancialSeeFiber |