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191.
I. J. Miller N. K. McCallum C. M. Kirk B. M. Peake 《Cellular and molecular life sciences : CMLS》1982,38(2):230-231
Summary The free radical oxidation of 1 and 6-tetrahydrocannabinol has been examined by spin trapping techniques and intermediates that would lead to cannabinol have been trapped. The 1st step in the oxidation of 1-THC involves the removal of 3-H, while for 6-THC, either 2-H or 5-H. Intermediates were isolated which could be pyrolysed to the diene and cannabinol. 相似文献
192.
The identification of ecdysterone (20-hydroxyecdysone) in 3 species of molluscs (Gastropoda: Pulmonata) 总被引:1,自引:0,他引:1
Summary Ecdysterone has been identified in the schistosomiasis vectorBiomphalaria glabrata Say and inHelix aspersa Müller as well as inLymmaea stagnalis L. by chromatography, bioassay, radioimmunoassay, derivatization and by mass spectroscopy. Analysis of the food, faeces and hepatopancreas suggest that the sterol is derived from the diet. The probable function of ecdysterone in relation to calcification of the shell is discussed in this paper.We wish to thank Professor P. Karlson and Dr J. Koolman (Phillips University, Marburg-Lahn, FRG) for providing facilities for RIA. The initial study was begun at the University of Sussex and continued at the Courtauld Institute of Biochemistry, Middlesex Hospital Medical School, London, while D.L.W. was supported by the Ministry of Overseas Development. London and the Medical Research Council of Great Britain (grant G974/525/T). We thank Mr P. Mellon for the mass spectrum and Dr G.B. Russell for his interest in the earlier part of this study. We also thank Professor E. Scherer and Dr Q. Uwe (University of Essen, FRG) for their help in the irradiation ofL. stagnalis.Gauss Str. 82, D-4630 Bochum 5 (Federal Republic of Germany). Research results usingL. stagnalis were submitted for the Philips Europa Wettbewerb für junge Forscher und Erfinder (1979) in a thesis entitled Zur Frage der Existenz von Steroiden und Gonadoliberin bei der Grossen Schlammschnecke (Lymmaea stagnalis L.): ein Beitrag zur Evolution der Insekten- und Wirbeltierhormone. 相似文献
193.
F. Imperato 《Cellular and molecular life sciences : CMLS》1982,38(1):67-68
Summary A new chalcone glucoside has been isolated from the flowers ofAcacia dealbata and shown to be 4,2,4,6-tetrahydroxy-3-methoxychalcone 2-O--D-glucoside (1) by chemical degradations and spectroscopic methods. Cernuoside (4,6,3,4-tetrahydroxyaurone 4-O--D-glucoside), (2) has also been found in this plant material.Acknowledgments. The author thanks Prof. H. Wagner, Institut für pharmazeutische Arzneimittellehre der Universität München, for a sample of homoeriodictyol, and Prof. J.B. Harborne, University of Reading, for a sample of aureusidin. 相似文献
194.
Genetic polymorphisms and intrauterine development. Evidence of decreased heterozygosity in light-for-dates human newborn babies 总被引:2,自引:0,他引:2
E. Bottini F. Gloria-Bottini P. Lucarelli A. Polzonetti F. Santoro A. Varveri 《Cellular and molecular life sciences : CMLS》1979,35(12):1565-1567
Summary In 2 independent samples of low-birth-weight infants the proportion of females and homozygotes for a series of polymorphic systems was higher in light-for-dates than in preterm babies. The observation seems to give support to the hypothesis that homozygosity for normal polymorphisms may decrease in general intrauterine growth rate. Since it is known that survival rate is strongly related to birth weight, a correlation between growth retardation and homozygosity may have a major role in the maintenance of such polimorphisms.We thank Prof. L. Ginzburg for helpful comments. 相似文献
195.
K. R. Middleton F. W. Schaefer H. J. Saz 《Cellular and molecular life sciences : CMLS》1979,35(2):243-244
Summary 4-Isothiocyanato-4-nitrodiphenylamine possessed anthelmintic activity againstNippostrongylus dubius andHymenolepis nana in mice andH. diminuta in rats as determined by both egg counts and recovery of parasites at autopsy. No activity was detected against the cestode,Spirometra mansonoides, in cats.This investigation was supported in part by grants AI-10512 and AI-09483 from the National Institutes of Health. The authors are indebted to Dr P.P. Weinstein for providing animals infected withSpirometra mansonoides. 相似文献
196.
F. Baccichetti F. Bordin F. Carlassare 《Cellular and molecular life sciences : CMLS》1979,35(2):183-184
Summary Furocoumarin photosensitization induces -prophage from lysogenicEscherichia coli cells; this effect is clearly due to the photoreaction that furocoumarins give with DNA, and it appears connected with the formation of monoadducts rather than of diadducts (cross-links).Acknowledgments. The authors wish to express their thanks to Dr L. Conventi, Microbiology Institute of Padua University, for generously donating theE. coli strains used in this work. 相似文献
197.
Summary In a group of 5 women taking oral contraceptives, the concentration of polymorphonuclear leucocytes along the gingival margin and the activities of cathepsin D, -glucuronidase and elastase were found to increase significantly during the intermenstrual phases.Supported by grant 3.604.075 of the Swiss National Fund for scientific Research. The authors thank Dr M. Baggiolini and Prof. A. Linder for the helpful advices. 相似文献
198.
Summary InTambourissa religiosa (Monimiaceae), the flowers are pollinated at a hyperstigma formed by the mouth of the floral cup, and not at the carpels. This is an extraordinary feature in angiosperms.I thank Professor Dr W. Rauh, Institut für Systematische Botanik und Pflanzengeographie der Universität Heidelberg, for providing material from his green house collection (W. Rauh, No. M 138, coll. 1959) and Dr Christa Güssefeld-Schneider for fixing pollinated flowers. 相似文献
199.
A. Borowska S. Sierakowski J. Maćkowiak K. Wiśniewski 《Cellular and molecular life sciences : CMLS》1979,35(10):1368-1370
Summary A correlation between the postirradiation increase of the small intestine motility and the prostaglandin-like activity in this organ during gastrointestinal syndrome was observed. Indomethacin decreased the elevated motility of intestine and reduced the prostaglandin-like activity in this syndrome.Acknowledgments. The work was supported by the Polish Academy of Sciences. 相似文献
200.
A. F. Furtado 《Cellular and molecular life sciences : CMLS》1979,35(8):1123-1124
Summary 2 factors elaborated by distinct neurosecretory cells in the pars intercerebralis control moulting inPanstrongylus megistus. The 1st, originating probably in the A cells, activates the thoracic gland. The 2nd, produced by the A cells, acts at an earlier stage in a different way.Supported by CNPq., Brésil and DGRST (aide No. 76.7.0716). 相似文献