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排序方式: 共有222条查询结果,搜索用时 15 毫秒
1.
E I Ermolenko L M Gerasimenko L B Borisov 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1989,(12):3-7
The comparative study of the biological properties of E. coli cultures, isolated from the urine of 7 patients two times during the first 11 days from the beginning of clinical manifestations of the exacerbation of chronic pyelonephritis, was conducted. In most cases the strains obtained as the result of the inoculations of the first and second urine samples belonged to the same serological and enzymatic variants. Still bacteria isolated in the second investigation, in contrast to E. coli obtained by the earlier inoculation of urine samples, often had no hemagglutinins and showed low adhesive capacity with respect to uroepithelium. Only in one out of 4 patient E. coli with antigen K1+ could be detected not only after the first inoculation, but also after the second one. In 4 patients E. coli cultures obtained as the result of the second isolation of these bacteria had lower content of sialic acid. Besides, differences in the sensitivity of E. coli strains isolated from the same patients in the course of the infectious process to the action of nonspecific protection factors of the body were established. The results obtained in the course of this study give more precise understanding of the existing conception of the pathogenesis of pyelonephritis. 相似文献
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Membrane proteins with a molecular weight of 290, 180, and 55 kDa were isolated using immunosorbent attached to sepharose and rabbit antibodies to cytoplasmic tetrodotoxin-sensitive protein from beef brain gray matter. A technique used for research into voltage-dependent sodium channels was applied to reconstruction of these proteins and investigation of toxin-dependent sodium flows through the lipoprotein membrane. Findings are interpreted as evidence of the similarity between cytoplasmic tetrodotoxin-sensitive protein and that of sodium channels at the cell membrane.A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev; A. V. Palladin Institute of Biochemistry, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 21, No. 4, pp. 485–489, July–August, 1989. 相似文献
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Excess amino acid polymorphism in mitochondrial DNA: contrasts among genes from Drosophila, mice, and humans 总被引:13,自引:3,他引:10
Recent studies of mitochondrial DNA (mtDNA) variation in mammals and
Drosophila have shown an excess of amino acid variation within species
(replacement polymorphism) relative to the number of silent and replacement
differences fixed between species. To examine further this pattern of
nonneutral mtDNA evolution, we present sequence data for the ND3 and ND5
genes from 59 lines of Drosophila melanogaster and 29 lines of D. simulans.
Of interest are the frequency spectra of silent and replacement
polymorphisms, and potential variation among genes and taxa in the
departures from neutral expectations. The Drosophila ND3 and ND5 data show
no significant excess of replacement polymorphism using the
McDonald-Kreitman test. These data are in contrast to significant
departures from neutrality for the ND3 gene in mammals and other genes in
Drosophila mtDNA (cytochrome b and ATPase 6). Pooled across genes, however,
both Drosophila and human mtDNA show very significant excesses of amino
acid polymorphism. Silent polymorphisms at ND5 show a significantly higher
variance in frequency than replacement polymorphisms, and the latter show a
significant skew toward low frequencies (Tajima's D = -1.954). These
patterns are interpreted in light of the nearly neutral theory where mildly
deleterious amino acid haplotypes are observed as ephemeral variants within
species but do not contribute to divergence. The patterns of polymorphism
and divergence at charge-altering amino acid sites are presented for the
Drosophila ND5 gene to examine the evolution of functionally distinct
mutations. Excess charge-altering polymorphism is observed at the carboxyl
terminal and excess charge-altering divergence is detected at the amino
terminal. While the mildly deleterious model fits as a net effect in the
evolution of nonrecombining mitochondrial genomes, these data suggest that
opposing evolutionary pressures may act on different regions of
mitochondrial genes and genomes.
相似文献
6.
Dr. I. V. Goncharova L. M. Gerasimenko G. A. Zavarzin G. T. Ushatinskaya 《Current microbiology》1993,27(4):187-190
In a culture of filamentous cyanobacteriumMicrocoleus chthonoplastes under high phosphorus content and the presence of NaF, formation of aggregated microtubes of 0.8–1.0 m in diameter was obtained. Microtubes contain calcium and phosphorus. These filamentous structures do not represent fossilized bacteria. 相似文献
7.
N. Yu. Gerasimenko A. V. Slavutskaya S. A. Kalinin E. S. Mikhailova 《Human physiology》2013,39(3):248-255
Psychophysiological experiments were performed on 34 healthy subjects. We analyzed the accuracy and latency of motor response in recognizing two types of complex visual stimuli, animals and objects, which were presented immediately after a brief presentation of face images with different emotional expressions: anger, fear, happiness, and a neutral expression. We revealed the dependence of response latency on emotional expression of the masked face. The response latency was lower when the test stimuli were preceded by angry or fearful faces compared to happy or neutral faces. These effects depended on the type of stimulus and were more expressive when recognizing objects compared to animals. We found that the effects of emotional faces were related to personal features of the subjects that they exhibited in the emotional and communicative blocks of Cattell’s test and were more expressive in more sensitive, anxious, and pessimistic introverts. The mechanisms of the effects of unconsciously perceived emotional information on human visual behavior are discussed. 相似文献
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Sara Santarossa Alexandra R. Sitarik Christine Cole Johnson Jia Li Susan V. Lynch Dennis R. Ownby Alex Ramirez Germaine LM. Yong Andrea E. Cassidy-Bushrow 《Journal of Exercise Nutrition & Biochemistry》2021,25(4):24
[Purpose] To determine whether physical activity (PA), primarily the recommended 60 minutes of moderate-to-vigorous PA, is associated with gut bacterial microbiota in 10-year-old children.[Methods] The Block Physical Activity Screener, which provides minutes/day PA variables, was used to determine whether the child met the PA recommendations. 16S rRNA sequencing was performed on stool samples from the children to profile the composition of their gut bacterial microbiota. Differences in alpha diversity metrics (richness, Pielou’s evenness, and Faith’s phylogenetic diversity) by PA were determined using linear regression, whereas beta diversity (unweighted and weighted UniFrac) relationships were assessed using PERMANOVA. Taxon relative abundance differentials were determined using DESeq2.[Results] The analytic sample included 321 children with both PA and 16S rRNA sequencing data (mean age [SD] =10.2 [0.8] years; 54.2% male; 62.9% African American), where 189 (58.9%) met the PA recommendations. After adjusting for covariates, meeting the PA recommendations as well as minutes/day PA variables were not significantly associated with gut richness, evenness, or diversity (p ≥ 0.19). However, meeting the PA recommendations (weighted UniFrac R2 = 0.014, p = 0.001) was significantly associated with distinct gut bacterial composition. These compositional differences were partly characterized by increased abundance of Megamonas and Anaerovorax as well as specific Christensenellaceae_R-7_group taxa in children with higher PA.[Conclusion] Children who met the recommendations of PA had altered gut microbiota compositions. Whether this translates to a reduced risk of obesity or associated metabolic diseases is still unclear. 相似文献