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VG Morozov VKh Khavinson AL Kozhemiakin LA Kozhemiakin 《Canadian Metallurgical Quarterly》1982,28(4):114-118
Thyramine, a polypeptide factor from thymus, at wide range of concentrations increased the cAMP content in rat thymocytes. Increase in the cAMP content was less distinct in spleen lymphoid cells. Thyramine decreased the cGMP content in thymocytes; minimal nucleotide level was found within 15 min of incubation. The data obtained suggest that the rate of lymphocyte maturation is important for response of the cells to the effect of immunoregulating agents. 相似文献
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LA Synder 《Canadian Metallurgical Quarterly》1976,69(6):764-767
Evaluation of roentgenographic studies of the lower cervical spine may be complicated by posttraumatic immobility, certain body types, and technical factors which produce equivocal findings. False-positive and false-negative findings are reported, with suggestions for additional views and more diagnostic evaluation. 相似文献
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Evidence for plasmid-associated crystal toxin production in Bacillus thuringiensis subsp. israelensis 总被引:1,自引:0,他引:1
RM Faust K Abe GA Held T Iizuka LA Bulla CL Meyers 《Canadian Metallurgical Quarterly》1983,9(1):98-103
Three crystalliferous (Cry+) strains of Bacillus thuringiensis subsp. israelensis (serotype 14) that produce parasporal protein crystals toxic to dipteran larvae and several acrystalliferous (Cry-) mutants, either induced or spontaneously derived from a single Cry+ parent, were examined for the presence of covalently closed circular (CCC) DNA in attempts to correlate toxin production with the presence of a specific plasmid. The plasmid profiles of both Cry+ and Cry- variants were analyzed by both a cleared lysate- and a modified Eckhardt lysate-electrophoresis technique. All of the Cry- mutants derived from the Cry+ parental strain had lost a 4.0- to 4.4-megadalton (Mdal) plasmid. Bioassay data confirmed loss of toxin production by the Cry- variants. All three Cry+ strains, including the parent of the Cry- strains, contained CCC plasmids DNAs of the following approximate molecular weights: 4.0 to 4.4, 5.2 to 6.0, and 11.4 to 13.0 Mdal. One Cry+ strain contained an additional CCC plasmid of 6.7 to 7.2 Mdal. The plasmid patterns for several Cry- derivatives differed in other respects from the pattern for their parent strain. The various Cry+ and Cry- strains could be distinguished either by phenotypical differences in antibiotic sensitivity, crystal production, and toxicity, or by differences in their plasmid profiles. 相似文献
136.
The intraperitoneal administration of pyridine, 3-methylpyridine and 3-chloropyridine to mice, hamsters, rats, guinea-pigs, rabbits and ferrets, resulted in the urinary excretion of their N-oxides. Pyridine-N-oxide was found to be a quantitatively important metabolite of pyridine in all the species studied; the percentage of the dose excreted in the urine as pyridine-N-oxide ranged from 10% in rats to about 40% in mice and guinea-pigs. 3-Chloropyridine-N-oxide and 3-methylpyridine-N-oxide accounted for less than 7% of the administered dose of the parent base. The urinary excretion of pyridine-N-oxide was considerably greater in mice pretreated with phenobarbitone, compared to control mice, whereas 3-methylchloranthrene pretreatment had no appreciable effect on the excretion of pyridine-N-oxide. 相似文献
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