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Saturnius papernai Overstreet, 1977 is recorded from the stomach of Mugil cephalus L. (Osteichthyes, Mugilidae) in the Black Sea (a new geographical record) off the southern part of the Bulgarian coast. The species is redescribed and figured on the basis of the Black Sea specimens. Some amendments to the generic diagnosis are proposed concerning the presence of a uterine seminal receptacle and a posterior (third) circular flange. It is proposed that the occurrence of S. papernai is a feature of one of the three shoals of M. cephalus in the Black Sea, i.e. the Balkan shoal. In a zoogeographical analysis, S. papernai is regarded as a Mediterranean immigrant, probably a characteristic element of only the South-Western Faunistic Region of the Black Sea. A review of the genus Saturnius Manter, 1969 is presented. 相似文献
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E. G. Boyko 《Contemporary Problems of Ecology》2013,6(3):262-267
A morphometric analysis of crustaceans from the genus Artemia inhabiting nine Ural and Siberian populations has been carried out. An effect of the total mineralization of water reservoirs and some ions on the characteristics of Artemia growth has been discovered. The number of setae on furca and its length are most affected by the factors under consideration. A trend toward a decrease in the manifestation of fluctuating asymmetry alongside an increase in the total mineralization of water reservoirs has been found. 相似文献
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Identification, sequencing, and enzymatic activity of the erythrose-4-phosphate dehydrogenase gene of Vibrio cholerae. 总被引:1,自引:1,他引:0 下载免费PDF全文
P A Carroll G Zhao S A Boyko M E Winkler S B Calderwood 《Journal of bacteriology》1997,179(1):293-296
We have identified a gene in Vibrio cholerae (epd) which encodes an erythrose-4-phosphate dehydrogenase activity and is located immediately downstream of an iron-regulated virulence gene, irgA, and immediately upstream of a gene encoding phosphoglycerate kinase (pgk). Expression of epd in V. cholerae is not regulated by iron, nor is it required for virulence in an infant mouse model. 相似文献
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V. A. Tarasov N. V. Boyko M. A. Makhotkin E. F. Shin M. G. Tyutyakina I. E. Chikunov A. V. Naboka A. N. Mashkarina A. A. Kirpiy D. G. Matishov 《Russian Journal of Genetics》2016,52(11):1117-1123
The dependence of expression of miRNAs and their precursors (pre-miRNAs) on the DNA methylation level in HeLa cells 8 days after mitomycin C treatment was studied. A massive parallel DNA sequencing method was applied to analyze miRNA expression. 5-Azacytidine (DNA methylation inhibitor) was added to the medium 6 days after mutagenic agent exposure. The results indicated that the change in expression for some mature miRNAs (39 of 61) was accompanied by the change in the expression of their pre-miRNAs, while there were no significant changes in the expression of pre-miRNA for other mature miRNAs (22 of 61). The aberrant expression was maintained by 8 of 61 mature miRNAs and 6 of 55 pre-miRNAs in the induced HeLa cells after 5-azacytidine treatment. In addition, the expression of more than 90% of miRNAs, which indicated a significant change in expression after mitomycin C treatment, does not depend or depends slightly on the DNA methylation level in HeLa cells without mitomycin C treatment. The results suggest that mitomycin C induces aberrant DNA methylation which affects maintenance of changes in the miRNA expression in cell generations after mutagen treatment. 相似文献
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Changes in regional body composition over 8 years in a randomized lifestyle trial: The look AHEAD study 下载免费PDF全文
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Disruption of microtubule organization and centrosome function by expression of tobacco mosaic virus movement protein 下载免费PDF全文
The movement protein (MP) of Tobacco mosaic virus mediates the cell-to-cell transport of viral RNA through plasmodesmata, cytoplasmic cell wall channels for direct cell-to-cell communication between adjacent cells. Previous in vivo studies demonstrated that the RNA transport function of the protein correlates with its association with microtubules, although the exact role of microtubules in the movement process remains unknown. Since the binding of MP to microtubules is conserved in transfected mammalian cells, we took advantage of available mammalian cell biology reagents and tools to further address the interaction in flat-growing and transparent COS-7 cells. We demonstrate that neither actin, nor endoplasmic reticulum (ER), nor dynein motor complexes are involved in the apparent alignment of MP with microtubules. Together with results of in vitro coprecipitation experiments, these findings indicate that MP binds microtubules directly. Unlike microtubules associated with neuronal MAP2c, MP-associated microtubules are resistant to disruption by microtubule-disrupting agents or cold, suggesting that MP is a specialized microtubule binding protein that forms unusually stable complexes with microtubules. MP-associated microtubules accumulate ER membranes, which is consistent with a proposed role for MP in the recruitment of membranes in infected plant cells and may suggest that microtubules are involved in this process. The ability of MP to interfere with centrosomal gamma-tubulin is independent of microtubule association with MP, does not involve the removal of other tested centrosomal markers, and correlates with inhibition of centrosomal microtubule nucleation activity. These observations suggest that the function of MP in viral movement may involve interaction with the microtubule-nucleating machinery. 相似文献