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131.
M E Krakovski? A Kh Ashirmetov Zh Iu Iuabova 《Nauchnye doklady vysshe? shkoly. Biologicheskie nauki》1991,(3):30-37
The microsomal cytochrome content and enzyme activity has been determined in liver, kidney, lungs and intestinal mucous from guinea pig males which were injected 25% ethanol intraperitoneally at a dose of 2 g per 1 kg of body mass. The changes in cytochrome P-450 and b5 content, amidopyrine-N-demethylase, aniline hydroxylase, p-nitrophenol hydroxylase. NADP.H-cytochrome-c-reductase activities in investigated organs of the animals have been found depending on the ethanol intoxication period (for 3, 6 or 14 days). Changes of the same type in microsomal enzyme activities have been discovered in liver, lungs and intestine, but not in kidney that is accounted for the substrate specificity and inducibility of the cytochrome P-450 some forms in extrahepatic tissues. 相似文献
132.
N S Egorov Zh K Loriia S N Vybornykh R Khamrun 《Prikladnaia biokhimiia i mikrobiologiia》1986,22(1):107-111
The effect of the culture medium composition on the bacitracin synthesis and sporulation in Bacillus licheniformis 28 KA was being studied. During the producer's growth on a medium with tripton a biphasic pattern of the process was observed, i.e. a rapid growth of the bacterial biomass was accompanied by the production of insignificant amounts of the antibiotic. The maximum efficiency of the antibiotic synthesis coincides with the end of the exponential growth phase and the onset of sporification. The efficiency of sporification amounts up to 95% when the above mentioned medium is used. The substitution of glutamate for trypton results in a dramatic deceleration of the bacterial growth and biomass accumulation, and the process of the antibiotic biosynthesis ceases to be biphasic, i. e. the antibiotic is synthesized during the trophophase. Under the conditions when the antibiotic production drops to zero by the middle of the exponential growth phase, sporulation is virtually suppressed. 相似文献
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Extinction of the defensive conditioned reflex in cats after lesioning the endopeduncularis nucleus]
T T Sarkisov L M Karapetian Zh S Sarkisian Kh M Mikaelian 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》2001,51(5):640-642
Influence of bilateral destruction of nucleus entopeduncularis on the extinction of conditioned avoidance was studied in 10 adult cats. It was shown that bilateral destruction of the nucleus entopeduncularis led to a disturbance of storage of the previous conditioning and facilitated repeated extinction. 相似文献
135.
A hybrid lambda att 80 phage with the genetic structure lambda (A-J) phi 80 (att-int-xis) imm lambda..cI857s7 is shown to be a convenient vector for creating transducing phages. On the one hand, the restriction analysis indicates that it has 3 restriction sites for EcoRI in comparison with 5 and 9 sites for parental phages lambda and phi 80 respectively. On the other hand, its buoyant density is less than that of phage lambda and under centrifugation it is easier separated from the phage transducing particles. When lambda att 80 prophage was excluded from the bfe locus of Escherichia coli, transducing phages with genes of two RNA polymerase beta-subunits (rpoB and rpoC) were isolated. To identify the latter, a convenient genetic test was worked out. A physical map of lambda att 80 drifd 35 transducing phage, carrying rpoB and rpoC genes has been constructed using endonucleases EcoRI and HindIII. A comparison of this map and the corresponding maps of transducing phages lambda drifd 18 and lambda drifd 47, studied earlier, led to the discovery of two integration sites of phage lambda within the locus bfe spaced apart by about 1800 nucleotide pairs. At all the sites both phages (lambda and lambda att 80) have integrated in the locus bfe in the counter clockwise order. 相似文献
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E N Goncharova S S Timoshin Zh D Bespalova S G Vyborov 《Biulleten' eksperimental'no? biologii i meditsiny》1992,113(6):647-649
The effect of atrial natriuretic factor (ANF) synthetic linear truncated analogues AP-H-6-OH and AP-FOR-6-OH on corneal, skin, duodenum and colon epithelium proliferation has been studied on male rats. The epithelium mitotic activity and DNA synthesis were evaluated 4 and 24 h after intraperitoneal injection of 10 or 100 micrograms/kg peptides. In a dose of 10 micrograms/kg both ANF synthetic analogues inhibited proliferation processes in corneal epithelium, but activated the DNA synthesis in duodenum and colon epithelium. AP-FOR-6-OH (10 micrograms/kg) decreased the mitotic activity of skin epithelium and increased the silver grain density over the cell nuclei at the same time. 100 micrograms/kg ANF analogues stimulated cell mitogenesis in all organs studied. According to the data obtained ANF linear truncated analogues influence on epithelium proliferation is similar to effector of previously studied cyclic atriopeptin AP II. 相似文献
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