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241.
Albert Eduardo Silva Martins Norma Lucena-Silva Renan Gomes Garcia Stefan Welkovic Aureliana Barboza Maria Luiza Bezerra Menezes Magda Maruza Terezinha Tenório Ricardo AA Ximenes 《Memórias do Instituto Oswaldo Cruz》2014,109(6):738-747
Human immunodeficiency virus (HIV)-positive patients have a greater prevalence of
coinfection with human papillomavirus (HPV) is of high oncogenic risk. Indeed, the
presence of the virus favours intraepithelial squamous cell lesion progression and
may induce cancer. The aim of this study was to evaluate the prevalence of HPV
infection, distribution of HPV types and risk factors among HIV-positive patients.
Cervical samples from 450 HIV-positive patients were analysed with regard to oncotic
cytology, colposcopy and HPV presence and type by means of polymerase chain reaction
and sequencing. The results were analysed by comparing demographic data and data
relating to HPV and HIV infection. The prevalence of HPV was 47.5%. Among the
HPV-positive samples, 59% included viral types of high oncogenic risk. Multivariate
analysis showed an association between HPV infection and the presence of cytological
alterations (p = 0.003), age greater than or equal to 35 years (p = 0.002), number of
partners greater than three (p = 0.002), CD4+ lymphocyte count <
200/mm3 (p = 0.041) and alcohol abuse (p = 0.004). Although high-risk
HPV was present in the majority of the lesions studied, the low frequency of HPV 16
(3.3%), low occurrence of cervical lesions and preserved immunological state in most
of the HIV-positive patients were factors that may explain the low occurrence of
precancerous cervical lesions in this population. 相似文献
242.
A D Vol'fson Iu A Motorin A Iu Tsygankov A F Orlovski? K L Gladilin 《Biokhimii?a (Moscow, Russia)》1988,53(5):799-805
The interaction of aminoacyl-tRNA synthetase with RNA and polyanions was studied. The inhibition of the enzymes by polyU, polyI and heparin was demonstrated. It was found that this interaction is of limited specificity and is typical of single-stranded RNAs which possess no orderly secondary structure as well as of other polyanions possessing similar polyelectrolytic properties. Data from kinetic analysis and lysyl-tRNA synthetase modification by pyridoxal phosphate are suggestive of participation of the tRNA binding site in the enzyme interaction with polyanions. 相似文献
243.
Possible ways for combining various biological processes of biohydrogen production are described. Some of these processes
are being intensively studied now, whereas others are theoretically feasible, but have not been studied. A special focus is
on the factors that influence the efficiency of coupled systems. 相似文献
244.
Photosynthesis Research - The results of homology modeling of HydSL, a NiFe-hydrogenase from purple sulfur bacterium Thiocapsa roseopersicina BBS, and deep-water bacterium Alteromonas macleodii... 相似文献
245.
A S Gorelyshev A M Kul'ba Iu D Tsygankov Iu K Fomichev 《Molekuliarnaia genetika, mikrobiologiia i virusologiia》1985,(9):3-6
The inheritance of plasmids Rms163 and R74 by Pseudomonas aeruginosa strain PAO hs been shown to effect the reproduction of a temperature bacteriophage SM. The decrease in plating efficiency of bacteriophage on Pseudomonas aeruginosa PAO (rms163) lawn is explained by the high degree of cell lysogenization by bacteriophage. Plasmid R74 inhibits bacteriophage SM propagation ultimately, evidently due to interruption of definite stages in vegetative development of bacteriophage by the products of plasmid specific genes. 相似文献
246.
Romanova A. I. Laurinavichene T. V. Tsygankov A. A. 《Russian Journal of Plant Physiology》2020,67(2):386-395
Russian Journal of Plant Physiology - Mutant strains of the filamentous cyanobacterium Anabaena strain PCC 7120 ΔHup (dc-Q193S and dc-R284H) with amino acid substitutions located in the... 相似文献
247.
Archives of Microbiology - 相似文献
248.
The study of Escherichia coli mutants synthesizing either hydrogenase 1 (HDK203) or hydrogenase 2 (HDK103) showed that the nitrate-dependent uptake of hydrogen by E. coli cells can be accomplished through the action of either of these hydrogenases. The capability of the cells for hydrogen-dependent nitrate respiration was found to depend on the growth conditions. E. coli cells grown anaerobically without nitrate in the presence of glucose were potentially capable of nitrate-dependent hydrogen consumption. The cells grown anaerobically in the presence of nitrate exhibited a much lower capability for nitrate-dependent hydrogen consumption. The inhibitory effect of nitrate on this capability of bacterial cells was either weak (the mutant HDK203) or almost absent (the mutant HDK103) when the cells were grown in the presence of peptone and hydrogen. Hydrogen stimulated the growth of the wild-type strain and the mutant HDK103 (but not the mutant HDK203) cultivated in the medium with nitrate and peptone. These data suggest that hydrogenase 2 is much more active in catalyzing nitrate-dependent hydrogen consumption than hydrogenase 1. 相似文献
249.
Anatoly A. Tsygankov Yoshiki Hirata Yasuo Asada Jun Miyake 《Biotechnology Techniques》1993,7(4):283-286
Summary A method for improving the adsorption of bacteria on glass surfaces was developed. The modification of a glass surface by LS-2480 greatly increased the number of bacteria that were immobilized. The conditions for bacteria immobilization on the modified glass surface were optimized. 相似文献
250.
S P Tsygankov N F Tarasenko A N Dergileva T P Sliusarenko V A Kovalenko 《Mikrobiologicheekij zhurnal》1985,47(1):36-40
Dynamics of the active sludge microorganism quantity is studied under different cultivation regimes. It is shown that quantity of microorganisms in different physiological groups depends on the specific growth rate, micro, determined by the dilution rate and biomass recirculation level. The results may be used for selecting optimal regime of the sewage treatment system functioning. 相似文献