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Studies on the metabolism of steroids in the foetus. Biosynthesis of 6α-hydroxytestosterone in the human foetal liver
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After incubation of testosterone with 105000g microsomes of human foetal liver, 6alpha-hydroxytestosterone was isolated and identified by t.l.c. and g.l.c.-mass spectrometry. This is the first example of 6alpha-hydroxylation of C(19) steroids in the human liver, and the finding is discussed in relation to earlier reports of 6-oxygenated C(19) and C(18) steroids in pregnant women. 相似文献
3.
M Giambiagi-Marval M A Mafra E G Penido M C Bastos 《Journal of general microbiology》1990,136(8):1591-1599
The genetic basis of bacteriocin (Bac) production by six strains of Staphylococcus aureus was examined. Gene transfer experiments (in which the plasmids were tagged with the erythromycin resistance transposon Tn551) and plasmid-elimination experiments by growth at 43 degrees C associated bacteriocin production with a particular plasmid in each strain. The Bac plasmids could be separated into two distinct groups: the first comprised plasmids larger than 40 kb, which did not specify immunity to bacteriocins; the second comprised small plasmids (8.0-10.4 kb) which also specified immunity to bacteriocins. The sequence relations among the small plasmids (pRJ6, pRJ9, pRJ10 and pRJ11) were investigated by comparing restriction enzyme digest patterns and by hybridization. Plasmids pRJ10 and pRJ11 were indistinguishable and very closely related to plasmid pRJ9. Plasmid pRJ6, although different from the others, shared regions of sequence homology with them. No homology was found between plasmids pRJ6 or pRJ9 and the large Bac plasmids. 相似文献
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Márcia Camargo-De-Morais Marta De Freitas Angela G. De Mattos Nádia Schröder Ana C. Zilles Carla S. F. Lisboa Nice Arteni Armando Barlem Rejane Schierholt Guilherme Zwetsch Carlos A. B. Souza Regina Pessoa-Pureur Carlos A. Netto 《Neurochemical research》1996,21(5):595-602
Neurofilaments subunits (NF-H, NF-M, NF-L) and glial fibrillary acidic protein (GFAP) were investigated in the hippocampus
of rats after distinct periods of reperfusion (1 to 15 days) following 20 min of transient global forebrain ischemia in the
rat. In vitro [14Ca]leucine incorporation was not altered until 48 h after the ischemic insult, however concentration of intermediate filament
subunits significantly decreased in this period. Three days after the insult, leucine incorporation significantly increased
while the concentration NF-H, NF-M, and NF-L were still diminished after 15 days of reperfusion. In vitro incorporation of32P into NF-M and NF-L suffered immediately after ischemia, but returned to control values after two days of reperfusion. GFAP
levels decreased immediately after ischemia but quickly recovered and significantly peaked from 7 to 10 days after the insult.
These results suggest that transient ischemia followed by reperfusion causes proteolysis of intermediate filaments in the
hippocampus, and that proteolysis could be facilitated by diminished phosphorylation levels of NF-M and NF-L. 相似文献
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Achiléa Lisboa Bittencourt Maria das Graças Santana Araujo Maria do Socorro Fontoura Paes 《Mycopathologia》1980,71(3):155-158
A case of a two-year-old boy with multiple subcutaneous lesions caused by Basidiobolus haptosporus is presented.The child had also a non-toxic familial goiter and clinical and radiological features of a pulmonary illness. The pulmonary manifestations only disappeared with the treatment with potassium iodide. The authors think that the pulmonary lesions must have arisen by direct spread of the fungus from the subcutaneous lesions of the chest. 相似文献
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A number of methods for the selective enrichment of recombinant plasmids were examined; these include alkaline phosphatase treatment of the restricted pBR322 vector, as well as a combination of this and S1 nuclease treatment of the ligated mixture of pBR322 and pCR1 plasmids orS. griseus DNA followed by D-cycloserine treatment to enrich for cells carrying recombinant molecules. The relative efficiencies of these methods were compared. 相似文献