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1.
S N Udintsev S G Krylova O N Konovalova 《Biulleten' eksperimental'no? biologii i meditsiny》1991,112(12):599-601
Rats exposed to stress by fixation develop a complex of hormonal metabolic homeostasis disturbances (as evidenced by changed levels of ACTH, insulin, 11-HOCS, urea, glucose). One of the major mechanisms of these disorders in reduced hypothalamus sensitivity to regulatory signals and exhausted adrenocortical functional activity, developing at the stages of anxiety and exhaustion of the adaptation syndrome, respectively, and detectable by functional tests with dexamethasone and ACTH. Administration of natural adaptogens (Scutellaria baicalensis extract and its active principle, baikalin flavonoid) was conducive to normalization of the majority of the examined parameters whatever the direction of changes. 相似文献
2.
The effect of nickel chloride concentrations in the range of 1–1000 mg/L on seed germination and the development of organs and pigment system in seedlings of the helophyte common water-plantain Alisma plantago-aquatica L. and hygrohelophyte greater water-parsnip Sium latifolium L. has been studied. It is shown that nickel chloride has practically no effect on the germination of the common water-plantain; however, it suppresses the germination of the greater water-parsnip. It is demonstrated that the toxicant suppresses the growth of seedlings and synthesis of photosynthetic pigments. The length of cotyledons and hypocotyl is less variable, with a much stronger effect on roots and leaves. It is determined that the morphometric parameters are less sensitive to the toxicant when compared to physiological ones. In general, the common water-plantain is more resistant to the effect of nickel chloride than the greater water-parsnip. 相似文献
3.
The population heterogeneity of recombinant and plasmid-free Bacillus subtilis strains introduced into aquatic microcosms was studied. After introduction, the population of the plasmid-free strain B. subtilis 2335 in microcosms has long been represented by both vegetative cells and spores, whereas, already ten days after introduction, the population of the recombinant strain B. subtilis 2335/105 (Km[symbol: see text]nf+) was represented only by spores. The number of plasmid copies in the spore isolates of the recombinant strain was the same as before introduction, but the plasmid abundance in the vegetative isolates of this strain decreased. The isolates of B. subtilis 2335/105 obtained from microcosms and the variants of this strain obtained by ten successive subcultures on M9 and 0.1 x M9 media with and without kanamycin (Km) differed in the number of plasmid copies, Km resistance, and maximum biomass yield during batch cultivation. Irrespective of the presence of Km, more than 50% of the variants subcultured on M9 medium showed reduced plasmid abundance. At the same time, about 70% of the variants subcultured on 0.1 x M9 medium with Km and 90% of the variants subcultured on the same medium without Km retained the initial number of plasmid copies. The variants subcultured on media with Km retained the initial biomass level. In more than 70% of the variants isolated from media without Km, the biomass yield increased. 相似文献
4.
T. Yu. Krylova L. Yu. Popova N. S. Pechurkin T. A. Kashperova V. A. Belyavskaya 《Microbiology》2000,69(2):220-224
The population heterogeneity of recombinant and plasmid-freeBacillus subtilis strains introduced into aquatic microcosms was studied. After introduction, the population of the plasmid-free strainB. subtilis 2335 in microcosms has long been represented by both vegetative cells and spores, whereas, already ten days after introduction,
the population of the recombinant strainB. subtilis 2335/105 (KmrInf+) was represented only by spores. The number of plasmid copies in the spore isolates of the recombinant strain was the same
as before introduction, but the plasmid abundance in the vegetative isolates of this strain decreased. The isolates ofB. subtilis 2335/105 obtained from microcosms and the variants of this strain obtained by ten successive subcultures on M9 and 0. I×
M9 media with and without kanamycin (Km) differed in the number of plasmid copies, Km resistance, and maximum biomass yield
during batch cultivation. Irrespective of the presence of Km, more than 50% of the variants subcultured on M9 medium showed
reduced plasmid abundance. At the same time, about 70% of the variants subcultured on 0.1 × M9 medium with Km and 90% of the
variants subcultured on the same medium without Km retained the initial number of plasmid copies. The variants subcultured
on media with Km retained the initial biomass level. In more than 70% of the variants isolated from media without Km, the
biomass yield increased. 相似文献
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6.
JR Sara SM Marr WJ Smit LJC Erasmus WJ Luus-Powell 《African Journal of Aquatic Science》2017,42(3):287-291
Muscle tissue from 63 Synodontis zambezensis collected bimonthly in 2013 at Flag Boshielo Dam were analysed for metals and metalloids in a desktop human health risk assessment. The Hazard Quotient, based on a weekly meal of 67 g of fish muscle, exceeded the maximum acceptable level of one for lead, cobalt, cadmium, mercury, arsenic and selenium. The concentrations of these elements were higher in 2013 than those recorded in 2009 and 2012 in other fish species from Flag Boshielo Dam and these may pose a long-term health risk if consumed regularly by impoverished rural communities reliant on fish as a source of protein. 相似文献
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Background
Microarray experiments, as well as other genomic analyses, often result in large gene sets containing up to several hundred genes. The biological significance of such sets of genes is, usually, not readily apparent. 相似文献10.