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931.
932.
Prenatal stress significantly reduced the number of progeny born to 47% of the female offspring and significantly increased the incidence of low birthweight young. None of these litters survived by the tenth postpartum day when serum prolactin levels were significantly reduced. Upon autopsy, these females had twice as many uterine implantation sites than the number of fetuses they bore, suggesting that a) the reduced postpartum serum prolactin most likely was the cause rather than the effect of the neonatal mortality and b) major hormonal deficiencies (possibly gonadotropic-related) were present even before giving birth. 相似文献
933.
934.
Summary The exogeneous application of cobalt induces the differentiation of membrane complexes of the endoplasmic reticulum. After longer acting of cobalt these membranes are dilated and later destroyed. This fact can manifest itself also in some disturbances of the cell division. 相似文献
935.
936.
E. J. Zöllner G. Seibert H. Slor R. K. Zahn 《Cellular and molecular life sciences : CMLS》1981,37(6):548-550
Summary The purification procedure for a nuclease from human serum is described. It includes ammonium sulfate precipitation, chromatography on DEAE-Sephadex and on Sephacryl-S 200, and preparative electrophoresis. The enzyme, purified about 2000-fold, is homogeneous in a sodium dodecyl sulfate electrophoretic system, where it has a mol. wt of 78,000. The pH optimum lies around pH 6.5; it is a sugar-nonspecific endonuclease.Acknowledgment. This work has been supported by a research grant from Stiftung Volkswagenwerk through the Akademie der Wissenschaften und der Literatur, Mainz. We thank Mrs R. Nehrbass and Mrs C. Wolpert for technical assistance. 相似文献
937.
Vascular smooth muscle from rabbits subjected to acute severe stress exhibits decreased sensitivity to sympathetic regulation. Stimulation of the sympathetic innervation of isolated vascular segments resulted in a similar subsensitivity as did exposure to norepinephrine (NE) but not histamine. Periodic contraction of these segments caused an increase in their maximum ability to contract independent of the constrictor procedure used. These results suggest that the increase in sympathetically mediated NE release that occurs in stress and some other pathological conditions may result in a blunting of neural control and possibly resistance to certain therapeutic agents. 相似文献
938.
L. Manzo R. Passoni A. D. Segre F. Bertè A. Crema 《Cellular and molecular life sciences : CMLS》1976,32(10):1318-1320
Summary Oxine-5-sulphonic acid inhibits the metabolism of aminopyrine in the rat liver in vitro. The characteristics of this inhibition vary according to whether the oxidativeN-demethylation of the substrate is determined by the formation of the metabolite 4-aminoantipyrine or by the production of formaldehyde. 相似文献
939.
940.