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101.
R. K. A. Giger H. R. Loosli M. D. Walkinshaw B. J. Clark J. M. Vigouret 《Cellular and molecular life sciences : CMLS》1987,43(10):1125-1130
Summary We report the synthesis, stereochemistry and preliminary pharmacological evaluation of DCN 203-922, a novel ergot alkaloid of the cyclol type, which contains in its peptide moiety the uncommon amino acid L-allo-isoleucine.Part of this paper was reported by this author at the Herbstversammlung der Schweizerischen Chemischen Gesellschaft, Bern, in October 1986. 相似文献
102.
Ross P Weinhouse H Aloni Y Michaeli D Weinberger-Ohana P Mayer R Braun S de Vroom E van der Marel GA van Boom JH Benziman M 《Nature》1987,325(6101):279-281
Cellulose is the most abundant renewable carbon resource on earth and is an indispensable raw material for the wood, paper, and textile industries. A model system to study the mechanism of cellulose biogenesis is the bacterium Acetobacter xylinum which produces pure cellulose as an extracellular product. It was from this organism that in vitro preparations which possessed high levels of cellulose synthase activity were first obtained in both membranous and soluble forms. We recently demonstrated that this activity is subject to a complex multi-component regulatory system, in which the synthase is directly affected by an unusual cyclic nucleotide activator enzymatically formed from GTP, and indirectly by a Ca (2+) -sensitive phosphodiesterase which degrades the activator. The cellulose synthase activator (CSA) has now been identified as bis-(3' 5')-cyclic diguanylic acid (5'G3'p5'G3'p) on the basis of mass spectroscopic data, nuclear magnetic resonance analysis and comparison with chemically synthesized material. We also report here on intermediary steps in the synthesis and degradation of this novel circular dinucleotide, which have been integrated into a model for the regulation of cellulose synthesis. 相似文献
103.
S. Burstein S. A. Hunter V. Latham L. Renzulli 《Cellular and molecular life sciences : CMLS》1987,43(4):402-403
Summary The results described here demonstrate that THC-induced catalepsy in mice can be substantially inhibited by the prior administration of 1-THC-7-oic acid, the major metabolite of THC in most species including humans. This raises the possibility that the intensity and duration of action of THC may depend to a large degree on the levels of this metabolite at the sites of action.We thank the National Institute on Drug Abuse for supporting this project by grants DA-02043 and DA-02052 and for supplying all of the cannabinoids. One of us (S.B.) is also the recipient of a Research Scientist Award from NIDA. We are grateful to Kristen Carlson and Thomas Honeyman for helpful suggestions in preparing this report. 相似文献
104.
105.
Androgen effect on genetic and goldthioglucose-induced obesity 总被引:1,自引:0,他引:1
106.
Growth of the bacterial cell 总被引:56,自引:0,他引:56
107.
108.
Abnormal electroretinogram from a Drosophila mutant 总被引:21,自引:0,他引:21
109.
Vertebrate blood oxygen capacity and body weight 总被引:1,自引:0,他引:1