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121.
Hybridization of deoxyribonucleic acid (DNA) from Lactobacillus bulgaricus (ATCC 11842) with DNA of L. lactis (ATCC 12315), L. helveticus (ATCC 15009), and L. jugurt (ATCC 521) showed 86.0% reassociation with L. lactis, 4.8% with L. helveticus, and none with L. jugurt. 相似文献
122.
Howard Feit Gary R. Dutton Samuel H. Barondes Michael L. Shelanski 《The Journal of cell biology》1971,51(1):138-147
The subunit protein of microtubules, tubulin, has been demonstrated to be present in isolated nerve endings by gel electrophoresis, amino acid composition, and peptide mapping. The tubulin constitutes approximately 28% of the soluble protein of the nerve endings. The transport of tubulin to the nerve endings has been demonstrated and its relationship to slow transport is discussed. 相似文献
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The free-living hermaphroditic nematode, Caenorhabditis briggsae, enters a dauer stage under certain conditions in axenic culture. Dauer larvae differ from directly-developing third-stage larvae in internal structure, size at time of second molt, morphology of second and third cuticles, separation zone of cuticular caps, and survival at 4 C and 37 C, temperatures fatal to other stages. Males, which occur rarely in liquid medium, may mature under conditions which cause most of the hermaphrodites to go into the dauer stage, resulting in a culture with increased male-to-hermaphrodite ratio. 相似文献
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Therapy of Staphylococcal Infections in Monkeys. IV. Further Comparison of Triacetyloleandomycin and Erythromycins 总被引:4,自引:2,他引:2
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Intravenous inoculation of a penicillin-resistant, phage type 80/81 staphylococcus caused lethal infection in 8 of 15 untreated monkeys. Daily intragastric administration of 50 mg/kg of triacetyloleandomycin, erythromycin estolate, and erythromycin ethylsuccinate was followed by mortalities of 0 of 16, 3 of 16, and 3 of 10, respectively. At dose levels of 25 and 12.5 mg/kg, none of 7 and 4 of 7 receiving triacetyloleandomycin and erythromycin estolate, respectively, died, as compared to 3 of 4 deaths in controls. In vitro sensitivity data and serum antibacterial levels would suggest that triacetyloleandomycin would be the least effective therapeutically. However, this prediction was not fulfilled in these studies of experimental infections in monkeys wherein triacetyloleandomycin was a very effective antimicrobial agent. 相似文献
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