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181.
Mechanism for the ''anti-lipolytic'' action of vasopressin in the starved rat. 总被引:2,自引:1,他引:1 下载免费PDF全文
The marked decrease in blood non-esterified fatty acids and ketone bodies after vasopressin infusion into starved rats [Rofe & Williamson (1983) Biochem. J. 212, 231-239] was investigated. Vasopressin did not inhibit lipolysis in isolated rat adipocytes. The metabolic effects in vivo were still present after pretreatment of rats with indomethacin, indicating that the effect is not secondary to the release of prostaglandins. Vasopressin significantly decreased blood flow through the retroperitoneal, epididymal and mesenteric fat depots, by 80%, 76% and 46% respectively. The specific haemodynamic effect of vasopressin on adipose tissue is considered to be the primary cause of the major metabolic changes seen in the starved rat. 相似文献
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Amino acid transport systems I and III in Neurospora are inhibited by amino acids in the intracellular pool (transinhibition). The transinhibition is system specific. The ability of an amino acid to transinhibit a transport system is highly correlated with its affinity for the system. The significance of the system specificity of transinhibition is discussed. 相似文献
185.
Localization of Parental Deoxyribonucleic Acid from Superinfecting T4 Bacteriophage in Escherichia coli 总被引:10,自引:7,他引:3 下载免费PDF全文
High-resolution autoradiography has been employed to localize the nonsolubilized but genetically excluded deoxyribonucleic acid (DNA) of T4 bacteriophage superinfecting endonuclease I-deficient Escherichia coli. This DNA was found to be associated with the cell envelope (this term is used here to include all cellular components peripheral to and including the cytoplasmic membrane); in contrast, T4 DNA in primary infected cells, like host DNA in uninfected E. coli, was found to be near the cell center. The envelope-associated DNA from super-infecting phage was not located on the outermost surface of the cell since it was insensitive to deoxyribonuclease added to the medium. These results suggest that DNA from superinfecting T-even phage is trapped within the cell envelope. 相似文献
186.
Attractant-Directed Motility in Escherichia coli: Requirement for a Fluid Lipid Phase 总被引:8,自引:4,他引:4 下载免费PDF全文
Attractant-directed motility (chemotaxis) in Escherichia coli has an absolute requirement for a fluid membrane. No such requirement was detected for motility per se. 相似文献
187.
R Parrilla K Okawa K O Lindros U J Zimmerman K Kobayashi J R Williamson 《The Journal of biological chemistry》1974,249(15):4926-4933
188.
Summary Uranyl sulphate (0.2–0.9 mM) inhibited ferrous iron oxidation by growing cultures ofThiobacillus ferrooxidans. The addition of 5–100 mM uranium to the cultures caused immediate cessation of carbon dioxide fixation, rapid loss of viability
and gradual depression of ferrous iron oxidation. Virtually no uranium was found in washed cells grown in the presence of
subtoxic to toxic amounts of uranyl sulphate. Uranium-poisoned organisms appeared plasmolyzed in electron micrographs. Cultures
tolerant to 5 mM UO2
2+ were develoepd by successive subculturing in increased uranium concentrations. The tolerance was maintained during subculturing
in uranium-free medium. Frequency of mutants resistant to 1.0 and 1.5 mM UO2
2+ was 1 per 1.3×106 and 1 per 9.0×108, respectively. The frequency was increased in the presence of 15–150 mM nickel, zinc and manganese. In liquid cultures, bivalent
cations and EDTA alleviated the toxicity of 2 mM uranyl sulphate. 相似文献
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