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1-(2-benzothiazolyl)-1-aryl-3-phenyl-4-arylguanidines (I-X) were prepared by oxidation of 1,3-diarylthioureas. The compounds were screened for their analgesic and hypnotic activities in rats. Of these, p-methyl group substituted compound of the series was the most potent analgesic as compared to other compounds of the series. In hypnotic test all the compounds potentiated pentobarbitone-induced hypnosis. 相似文献
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Analysis of the relative amount and distribution pattern of phloem sclerenchyma in some 29 tropical trees of India was carried out with systematic considerations. Both the features exhibited considerable diversity among the species analyzed. The extent of area occupied by sclerenchyma in transections of the bark of these species varied from zero to 35% and 3 to 49% in the conducting and non-conducting phloem zones respectively, the overall amount constituting about 3 to 45% of the secondary phloem as a whole. The sclerenchyma cells differentiated either as isolated elements or in the form of bands or fascicles of diverse shape and size showing various distribution patterns. 相似文献
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Eight strains of Neisseria meningitidis belonging to different serogroups were analysed for their virulence in mice and their release of outer membrane proteins into the medium during growth. All strains released proteins. No detectable lipopolysaccharide was observed. However, SDS-PAGE showed a heterogenicity in the protein number and profile among the different strains of N. meningitidis tested. 相似文献
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Curzen N Khawaja S Rothman M 《International journal of cardiovascular interventions》1999,2(2):117-119
We describe the treatment of a bifurcation lesion at the anastomosis of a vein graft by 'true Y' stenting which preserved both antegrade and retrograde flow away from the graft. 相似文献