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Summary We have measured the UV-spectra of liver chromatin extracted at 2 different times of day, corresponding to low or high rate of RNA synthesis from rats maintained under controlled feeding schedules. Results show that food intake does modify the UV-spectra of liver chromatin.  相似文献   
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Summary The effects of time and various doses of testosterone on the responsiveness of lactate dehydrogenase of pituitary of 7-, 38- and 78-week-old rats were studied. The activity of the enzyme increases in 78-week-old rats. Castration decreases the enzyme activity at all ages. Maximum increase in the enzyme activity is seen with 50 and 100 g of testosterone 4 h after administration of hormone to castrated rats. No further time and dose-dependent effect is observed. The magnitude of increase for the enzyme is higher at the age of 38 weeks and decreases in 78-week-old rats.To whom all correspondence should be addressed. The authors are grateful to Professor M.S. Kanungo, Biochemistry Laboratory, Department of Zoology, Banaras Hindu University for the suggestions and encouragement. K.V.G. thanks the PL-480 for a research fellowship.  相似文献   
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Deposition of amyloid β-protein (Aβ) in the brain is an early and invariant neuropathological feature of Alzheimer’s disease (AD). The current search for anti-AD drugs is mainly focused on modification of the process of accumulation of Aβ in the brain. Here, we review four anti-amyloidogenic strategies: (i) reduction of Aβ production, which has mainly been approached with secretase inhibition, (ii) promotion of the Aβ degrading catabolic pathway, including an Aβ degrading enzyme, neprilysin, (iii) immunotherapy for Aβ and (iv) inhibition of Aβ aggregation. We have reported that AD patients have a favorable molecular environment for Aβ aggregation and that various compounds, such as polyphenols, interfere with Aβ aggregation and destabilize preformed Aβ fibrils. Received 21 December 2005; received after revision 14 February 2006; accepted 29 March 2006  相似文献   
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Zusammenfassung Aus den Biberdrüsen wurdecis-Cyclohexan-1,2-diol isoliert und charakterisiert.

The support of this work by the Colombo Plan administration of Canada is gratefully acknowledged.  相似文献   
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Summary The inducing factor of mating tube formation ofRhodosporidium turuloides, named rhodotorucine A (H-Tyr-Pro-Glu-Ile-Ser-Trp-Thr-Arg-Asn-Gly-Cys(S-farnesyl)-OH), has been synthesized to confirm the structure proposed for the natural lipopeptide. The synthetic S-farnesyl undecapeptide has identical Rf values on TLC using several different solvents, and also the same biological activity as the natural hormone.Acknowledgments. We wish to express our thanks to Drs E. Ohmura, M. Nishikawa and M. Yoneda of Takeda Chemical Industries and Dr I. Banno of Institute for Fermentation, Osaka, for their encouragement throughout this work.  相似文献   
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Summary Significant decreases in the levels of both carbonic anhydrase type B and total esterase activity of human erythrocytes were observed after physical exercise (bicycle ergometer, 150 W for 30 min). Since carbonic anhydrase B-dependent esterase activity likewise decreased, the decrease in the total esterase activity would be caused by the decrease of carbonic anhydrase B activity. The specific activity of carbonic anhydrase B tended to decrease after the exercise. On the other hand no such effects were noted for carbonic anhydrase type C.  相似文献   
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