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111.
W. D. MacRae G. F. Q. Chan Chi-Kit Wat G. H. N. Towers J. Lam 《Cellular and molecular life sciences : CMLS》1980,36(9):1096-1097
Summary -Terthienyl and 5 polyacetylenes were examined for chromosome damaging activity using Syrian hamster cells. None of these naturally occurring compounds induced sister chromatid exchanges and neither -terthienyl nor phenylheptatriyne induced chromosome aberrations.The authors wish to thank the National Science and Engineering Research Council for financial support of this research. 相似文献
112.
Summary
-adrenoceptor stimulation by isoprenaline increases the potassium efflux in beating guinea-pig atria. This effect is not mimicked by 8-bromo-cyclic AMP, a cyclic AMP analogue which exerts a positive inotropic effect in this preparation. 相似文献
113.
D. V. Amin R. B. Doctor A. O. Girdhar U. H. Shah 《Cellular and molecular life sciences : CMLS》1980,36(12):1410-1411
Summary Prostaglandin (PG) release was measured from the isolated perfused rabbit heart. The effects of -adrenergic stimulation and blockade suggest that PG synthesis is regulated in part by adrenergic mechanisms. 相似文献
114.
H. Watanabe J. A. Menzies J. C. K. Loo 《Cellular and molecular life sciences : CMLS》1981,37(8):883-884
Summary Isonicotinic acid hydrazide (isoniazid) was shown to react readily with 17-ethinyl-17-hydroxyestr-4-en-3-one (norethindrone) to form the isonicotinyl hydrazone of the steroid under conditions likely to exist in the stomach. The hydrazone was detected in guinea-pig, but not rat, plasma following its oral administration. Rat liver tissue metabolized the compound more rapidly than guinea-pig liver in vitro which probably accounts for the failure to detect the hydrazone in rat plasma. 相似文献
115.
B. Lejczak H. Starzemska P. Mastalerz 《Cellular and molecular life sciences : CMLS》1981,37(5):461-462
Summary Analogues of glutamic acid, -methylglutamic acid and glutamine in which the -or -COOH groups are replaced by PO3H2 or P(O)(OH3)OH functions competitively inhibit rat liver glutamine synthetase. The K1 values are comparable to or lower than KM for L-glutamate.This study was supported by grant R.1.9. 相似文献
116.
R. Lenzhofer C. Cerni I. Fröhlich J. Prager H. Pointner 《Cellular and molecular life sciences : CMLS》1981,37(9):1015-1017
Summary The influence of somatostatin on tumor cell growth was studied in vivo in mice (sarcoma 180 ascites tumor and Lewis lung tumor) and in vitro on nontransformed and polyoma-transformed cell lines. 4 or 20 g/100 g of cyclic somatostatin and 4 g/100 g of linear protamin Zn-bound somatostatin were injected s.c. twice daily in the in vivo study. Cyclic somatostatin (1, 4 or 10 g/ml) was added twice daily to the cell cultures. Somatostatin administration influenced neither the survival of animals nor the growth rate of cultured cell lines. *** DIRECT SUPPORT *** A2025117 00011 相似文献
117.
H. Takeuchi T. Morimasa M. Matsumoto 《Cellular and molecular life sciences : CMLS》1977,33(7):938-939
Summary Several peptides were separated from-chymotrypsin-treated physalaemin by high voltage paper electrophoresis, and inhibition of the excitability of a molluscan giant neurone (tonically autoactive neurone) by the tripeptide, Lys-Phe-Tyr, was demonstrated.We thank Dr Sadaaki Iwanaga of Osaka University and Dr Atsuo Inoue of Daiichi Pharmaceutical CO for their helpful advice and the donation of the tripeptide (Lys-Phe-Tyr). 相似文献
118.
For the identification of a peptidyl principle inducing sexual agglutination in the yeast, 2 supposed hexapeptides (1a, b) were synthesized by the conventional method. The 1a (H-Arg-Gly-Pro-Phe-Pro-Ile-OH) revealed complete identity with the natural peptide in TLC, MS and biological property on agglutination. The 1b showed the sexual agglutinability in the same degree as 1a, though distinct differences were observed in the chemical data. Both 1a and 1b had a strong bitter taste. 相似文献
119.
In vivo studies indicated that the primary effects of E. coli endotoxin on hepatic clearance of sulfobromophthalein were at the excretory level. Newborns were more sensitive to the LPS than older animals. 相似文献
120.
J. Kapitola H. Dlouhá Dr. J. Křeček J. Zicha 《Cellular and molecular life sciences : CMLS》1977,33(12):1615-1616
Summary Neurohypophyseal blood flow increases in water-deprived rats. This increase is independent of vasopressin release, since it occurs even in rats with hereditary defect of hypothalamic vasopressin synthesis.Acknowledgment. The technical assistance of D. Vilimovská is acknowledged. 相似文献