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941.
E R Dalferes B Radhakrishnamurthy M S Crouch G S Berenson 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1975,148(3):918-924
The effect of obesity on the connective tissue composition of skin was investigated in mice with goldthioglucose (GTG)-induced obesity. Four months after GTG treatment, the obese animals were sacrificed. Acid mucopolysaccharides, glycoproteins, collagen, and elastin were analyzed in the skin and compared to the controls. Total MPS in the skin from obese animals decreased, reflected mostly in hyaluronic acid. Chondroitin showed an increase over controls. The content of soluble glycoproteins varied; total carbohydrate and sialic acid of the glycoprotein tended to increase with obesity. Collagen and elastin both tended to decrease with obesity. 相似文献
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The epithelium of the rim of the octopus sucker is the site of several different types of primary receptors. One is a non-ciliated cell with unusual characteristics. (1) The surface of the cell is extremely irregular with finger-like extensions of cytoplasm, especially far reaching in the basal region. (2) The slender neck contains a canal whose apical opening is in contact with the environment. This canal is lined with microvilli and contains granular material in an electron-dense matrix. (3) Patches of presumed glycogen granules occur throughout the cell, being especially abundant in the outer reaches of the cytoplasmic extensions. Their presence, together with numerous mitochondria and free ribosomes, indicate a high intrinsic metabolism. (4) Small fascicles of microtubules are randomly situated throughout the perikaryon. They gather into a coherent system of larger and larger bundles which ultimately enter the axon leading from the cell. This axon extends some distance in the basal region of the epithelium before crossing the subepithelial space to enter the infundibular muscle. Possible functions of this cell are discussed. On the basis of its specific position on the sucker and its intrinsic morphology we suggest that it is a mechanoreceptor involved in shape and/or negative pressure discrimination. 相似文献
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Antigenic change on the surface of immature oocytes of Ascaris occurred during passage through the oviduct. Using immunodiffusion and immunoelectrophoretic techniques we examined the possible relationship between the antigenic change of immature oocytes and the junctional fluid (JF) which is present in the fertilization chamber. From the immunodiffusion it was found that the anti-immature oocyte serum (A-I serum) had more immunoprecipitation arcs than did the anti-mature oocyte serum (A-M serum) when reacted against the junctional fluid. This indicated that A-I serum contained more immunoglobulins that reacted with junctional fluid than did the A-M serum. This result was substantiated by using immunoelectrophoretic analysis and two dimension crossed immunoelectrophoresis. Our results suggest that during the migration toward the oviduct-uterine junction the immature oocytes might shed surface proteins into the luminal fluid. Alternatively, the membrane surface of mature oocytes may be altered by the interaction with the substances present in the junctional fluid. 相似文献