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81.
A K Roy B Chatterjee W F Demyan T S Nath N M Motwani 《The Journal of biological chemistry》1982,257(13):7834-7838
Hypophysectomy is known to cause complete suppression of the hepatic synthesis alpha 2u-globulin. The effect of hypophysectomy on the synthesis of alpha 2u-globulin can be reversed by multiple hormone treatment. The role of pituitary growth hormone in the multihormonal regulation of alpha 2u-globulin in rat liver was examined in the hypophysectomized male rats with and without growth hormone supplementation. Daily treatment of hypophysectomized rats with 5 alpha-dihydrotestosterone, corticosterone, thyroxine, and growth hormone for 8 days caused about 80% recovery in the hepatic content of alpha 2u-globulin and its corresponding mRNA as determined by radioimmunoassay, in vitro translation, and liquid hybridization with a cloned cDNA probe. However, omission of growth hormone from the treatment regimen failed to raise hepatic alpha 2u-globulin and its mRNA to more than 5% of the normal control. The possible effect of growth hormone on the translation of the mRNA for alpha 2u-globulin was examined with cultured hepatocytes derived from growth hormone-deficient rats. Culture of these cells in the presence of growth hormone for 24 h did not turn on the synthesis of alpha 2u-globulin. These results indicate that growth hormone regulates the synthesis of alpha 2u-globulin by acting at a step antecedent to mRNA translation. 相似文献
82.
Flat bones of human skeleton were subjected to dynamic indentation with ball indenters. The impacted surface was studied under
high magnification and also by using the technique of multiple beam interferometry. The impulse caused the pile up of material
at a little distance from the edge of the indent. The diameter of indent is found to increase as fourth root of the energy
of impact. Bone structure also has the tendency to minimize the damage caused by external forces. There was about 90% recovery
in deformation in the depth of indents due to internal stresses created inside the bone by the impact. 相似文献
83.
The antimicrobial activities of six withanolide compounds are compared. 相似文献
84.
85.
Martijn H. Breuning Ella M. van den Berg-Loonen Luigi F. Bernini Jan B. Bijlsma Erna van Loghem P. Meera Khan Lourens E. Nijenhuis 《Human genetics》1977,37(2):131-139
Summary A detailed marker gene study in a large Dutch kindred segregating for a reciprocal translocation between the chromosomes 6 and 20, t(6;20) (p21;p13), revealed a close linkage between the HLA genes and the breakpoint on the short arm of 6. During this study an apparent peak lod score of 2.9 was obtained at a recombination value of 0.05 for a linkage between HLA and the breakpoint, indicating that the chromosomal region, carrying the HLA genes, is situated near the breakpoint in band 6p21 close to the transition to 6p22. 相似文献
86.
87.
Biodegradation of 2,4,5-trichlorophenoxyacetic acid in soil by a pure culture of Pseudomonas cepacia. 总被引:12,自引:11,他引:1 下载免费PDF全文
A pure culture of Pseudomonas cepacia AC1100 was able to degrade and grow in presence of 2,4,5-trichlorophenoxyacetic acid in soil. At optimum temperature (30 degrees C) and moisture content (15 to 50% [wt/vol]) strain AC1100 could degrade as much as 95% of 2,4,5-trichlorophenoxyacetic acid at high concentration (1 mg/g of soil) within 1 week. 相似文献
88.
Biodegradation of 2,4,5-trichlorophenoxyacetic acid by a pure culture of Pseudomonas cepacia. 总被引:32,自引:19,他引:13 下载免费PDF全文
J J Kilbane D K Chatterjee J S Karns S T Kellogg A M Chakrabarty 《Applied microbiology》1982,44(1):72-78
A pure culture of Pseudomonas cepacia, designated AC1100, that can utilize 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) as its sole source of carbon and energy was isolated. An actively growing culture of AC1100 was able to degrade more than 97% of 2,4,5-T, present at 1 mg/ml, within 6 days as determined by chloride release, gas chromatographic, and spectrophotometric analyses. The ability of AC1100 to oxidize a variety of chlorophenols and related compounds is also reported. 相似文献
89.
Chloramphenicol production was studied in cultures of Streptomyces venezuelae growing in a simple buffered medium with ammonia as the nitrogen source and glucose, lactose, or a glucose-lactose mixture as the sole source of carbon. With each carbon source the antibiotic was formed during growth. In the glucose-lactose medium, the production pattern was biphasic; a marked decrease in the rate of synthesis was associated with depletion of glucose from the medium and a corresponding diauxie pause in growth. Cells of S. venezuelae contained an inducible beta-galactosidase. Induction by lactose was suppressed by glucose. Measurement of the concentration of intracellular adenosine 3',5'-cyclic monophosphate during growth of cultures with glucose or a glucose-lactose mixture as the source of carbon showed no appreciable changes coinciding with depletion of glucose or the onset of chloramphenicol biosynthesis. It is concluded that the cyclic nucleotide does not mediate selective nutrient utilization or control antibiotic biosynthesis in this organism. 相似文献
90.
A bacterium isolated from Assam (India) soil was found to accumulale l-lysine from hydrocarbon and was identified as a strain of Micrococcus varians. The strain is able to grow and accumulate lysine in a purely synthetic medium though supplementation of the synthetic medium with casamino acids significantly improves the yield. The yield of l-lysine under optimal conditions was found to be 2.6 g X 1(-1) of the compound isolated in crystalline form. 相似文献