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731.
732.
733.
Lipid peroxidation and activities of antioxidative enzymes were studied in the brain cortex after short (15 min) cerebral ischemia and reperfusion (10 min) in rats. Conjugated dienes (CD) and thiobarbituric acid-reactive substances (TBARS) were significantly elevated in the group of rats with ischemia followed by reperfusion in comparison to the ischemic animals. Superoxide dismutase (SOD) activity significantly increased in the group of animals with ischemia and reperfusion. No significant changes in the activities of glutathione peroxidase (GP) were observed. Stobadine administered before ischemia or before reperfusion decreased the level of TBARS. Stobadine probably prevents malondialdehyde (MDA) formation from hydroperoxide or might elevate the activity of aldehyde dehydrogenase. In contradiction to the findings after long-lasting (4 h) ischemia and subsequent reperfusion, no decrease in the concentration of CD or in the activity of SOD or GP was found. 相似文献
734.
P. D. M. V. Turlapaty B. T. Altura B. M. Altura 《Cellular and molecular life sciences : CMLS》1979,35(5):639-640
Summary The present results, using isolated rat aortic strips and portal vein segments, demonstrate that ethanol (170–430 mM) significantly inhibits calcium uptake in these 2 different types of vascular smooth muscle.Supported by NIH grant No. HL-18015 and NIMH grant No. MH-26236. Request for reprints should be addressed to B.M. Altura. 相似文献
735.
Plasma progesterone, testosterone, total estrogens and immunoreactive gonadotropin were measured in nesting and non-nesting sea turtles, Chelonia mydas. Progesterone and gonadotropin concentrations were significantly higher in nesting than in non-nesting turtles, testosterone was not significantly different in either group and total estrogens appeared to be slightly in the nesting group. 相似文献
736.
G F Collet V Pont 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1978,286(9):681-684
The methyl 2-chloro-3 (4-chlorophenyl) propionate is quickly hydrolysed through coleoptiles of wheat (coleoptile test). Then, depending on the concentration of the compounds, one observes mainly a further degradation (at 0,01 mM) of the acid or conjugation (at 0,1 mM) of it with cystein in vivo. This second type of physiological neutralisation appears to be more efficient than the catabolism which give derivatives of benzoic acid. 相似文献
737.
A. M. Bobst T. V. Wang P. A. Cerutti 《Cellular and molecular life sciences : CMLS》1981,37(6):597-598
Summary Scavenging studies are supporting the notion that triplet radical cations are formed during the binding of the carcinogen N-acetoxy-2-acetylamino-fluorene to native DNA in vitro.This work was supported by Grant No.3305.78 of the Swiss National Science Foundation and by a grant from The Roche Research Foundation. 相似文献
738.
A. Laubscher A. Pletscher C. G. Honegger J. G. Richards V. Colombo 《Cellular and molecular life sciences : CMLS》1979,35(8):1081-1083
Summary Myelin basic protein (MBP) isolated from bovine spinal cord caused a marked shape change reaction of human blood platelets which was not accompanied by the release reaction and not inhibited by methysergide and spiroperidol. Only those basic proteins, including MBP, which had previously shown to exert neuronal depolarisation also induced the shape change reaction. Therefore, these findings may extend the use of platelets as neuronal models.Acknowledgment. We thank Miss B. Gieux and Miss M. Handschin for skilful technical assistance. 相似文献
739.
O. Flore M. A. Marcialis M. E. Marongiu R. Pompei P. La Colla B. Loddo 《Cellular and molecular life sciences : CMLS》1977,33(9):1155-1157
Summary Dichloropyrimidines can be considered as a new group of antiviral substances having a common spectrum of inhibitory action.This work has been supported by a grant of Consiglio Nazionale delle Ricerche, Rome (Italy). 相似文献
740.
The distribution of fast, intermediate and slow renaturing fractions of Rhynchosciara americana DNA was examined in the polytene salivary gland chromosomes by in situ hybridization. Heterochromatic areas readily hybridized but hybrid formation in the euchromatin depended more on the repetitiveness of the RNA probe. 相似文献