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601.
Sleep and Biological Rhythms - The effects of a delayed and/or disturbed sleep-wake pattern on mental functioning, frequently found in university students, were confirmed by several studies. The... 相似文献
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Tomoko Yamaguchi Keirei Hayashi Hirohiko Murakami Shoichi Maruyama Masashi Yamaguchi 《Neurochemical research》1984,9(4):497-505
In a search for neurochemical involvement in cerebellar ataxia, Rolling Mouse Nagoya (C3Hf/Nem-rol), which shows only hypoplasia of the cerebellum but no pathological configuration of the cerebellar structure, was used to study glutamate receptors in the CNS. Kainic acid binding sites were significantly decreased in the thalamus, hypothalamus, pons, and cerebellum, and in the frontal cortex of both the ataxic mutant mouse and the non-ataxic heterozygote. Only spinal cord and midbrain of the ataxic mutant mouse showed decreased distribution of kainate binding sites in the membrane fraction.Among enzymes responsible for supplying glutamate to the receptor, GDH showed higher activity in the spinal cord of the ataxic mutanat mouse. 相似文献
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The angular dependence of light scattering and the concentration dependence of the relative viscosity have been measured in solutions of o-nitrophenylthio-hexa-(γ-benzyl-L -glutamate) ethylamide in ethylene dichloride. Both the reduced intensity of scattered light and the reduced viscosity of the solution suddenly increase above a certain critical concentration, below which both of them remain low and constant. The Debye plot of light scattering indicates that primary micelles having an aggregation number 48 are formed at the critical micelle concentration and that secondary micelles, each consisting of 294 molecules, then appear in increasing amounts with increasing concentration beyond the critical micelle concentration. The secondary micelle is rodlike and has a length of 1170 Å, if it is rigid. An analysis of the reduced viscosity leads to the intrinsic viscosity for the primary micelle, 0.360 dL g?1, and to that of the secondary micelle, 1.28 dL g?1. If the secondary micelle is represented by a prolate ellipsoid, it should have an axial ratio of 47. If the polypeptide chains are extended in the micelle, the observed aggregation number and axial ratio of the secondary micelle can well accommodate the intermolecularly hydrogen-bonded in-register β-structure of anti-parallel chains. In the primary micelle, some folded polypeptide chains are involved, and an intermolecularly hydrogen-bonded out-of-register structure would form a rather open network. 相似文献