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891.
Addition of Tween 80 to the growth medium brings about qualitative and quantitative changes in the lipids of Mycobacterium phlei ATCC 354. The results suggest that Tween 80 itself may be a variant in the system. 相似文献
892.
K J Mikolajczak R V Madrigal J K Rupprecht Y H Hui Y M Liu D L Smith J L McLaughlin 《Experientia》1990,46(3):324-327
Sylvaticin (I), a new tetrahydroxy annonaceous acetogenin with nonadjacent tetrahydrofuran rings, has been isolated from the dried fruits of Rollinia sylvatica St. Hil. (Annonaceae). This compound is extremely cytotoxic to human tumor cells and shows promising insect control properties. 相似文献
893.
Two insect development inhibitors against Drosophila melanogaster have been isolated from the leaves of X. canadense and identified as xanthumin and 8-epi-xanthatin. 相似文献
894.
895.
The direct effect of serotonin and antiserotonin agents on adrenal steroid biosynthesis was studied in isolated adrenal cells derived from patients with Cushing's syndrome. The results indicate that serotonin increases corticosterone production, while the serotonin antagonists cyproheptadine and methysergide depress adrenal steroid - particularly cortisol and aldosterone - biosynthesis. 相似文献
896.
Lipoperoxidation and drug-metabolizing enzymes were measured in livers and placentas of different mammal species during the perinatal perios. In placentas and fetal livers of rat, rabbit and guinea-pig, cofactor-supported lipoperoxidation was negligible, as were the activities of drug-oxidizing enzymes. Human fetal liver contained an intact drug-oxidizing electron transport chain, and lipoperoxidation activity was accordingly abserved. It is suggested that lesions mediated by lipoperoxidation may be possible in human fetus, but they are less probable in animal fetuses. 相似文献
897.
Hep-2 cells infected with measles virus (MV) for as short as 6 h became refractory to superinfection with canine distemper virus (CDV) but not to vesicular stomatitis virus (VSV). The exact mechanism of such interference is unknown but probably occurs after virus attachment and penetration. These results verify the suggestion that virus interference may be a mechanism of heterotypic protection against canine distemper. 相似文献
898.
Effects of chinoform and chinoform-ferric chelate on formation of lipoperoxide in isolated sciatic nerve were investigated. Free chinoform did not increase the lipoperoxide level, while chinoform-ferric chelate significantly increased it. Assuming that the lipoperoxide formed denatures the associated protein in the nerve, the effect of chinoform-ferric chelate could explain, at least partly, the demyelination of nerve tissues caused by massive doses of chinoform. 相似文献
899.
900.