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K G Gapochko I D Kudrin T V Sambukova A P Savel'ev 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1990,(7):55-59
Healthy volunteers with quite opposite emotional properties defined by means of Cattell Personality Questionnaires were shown to have essential differences in their postvaccinal reactions. These differences were seemingly caused by psychoemotional tension developing in unstable persons as a result of their perception of vaccination as a threatening factor. The administration of Phenasepam (3 mg) decreased such emotional tension and thus removed negative reactions at the postvaccinal period. The preparation had no influence on the production of protective antibodies to all types of antigens used for immunization. 相似文献
3.
S V Savel'ev 《Ontogenez》1988,19(2):165-174
The embryonic brain was dissected in urodele amphibians at the early postneurulation stages. Tangential mechanical tensions were shown to exist in the embryonic brain. The reaction of neuroepithelial cells characterizing the topology of tensions was found by the use of dissections in two interperpendicular directions. The cells were oriented along the acting force in the case of unidirectional tension. In the case of two interbalanced tensions the cells were inclined along the lines of force of greater tension. Three types of tangential tensions were revealed which differ in force, direction, range of action and life time. The life times of tangential tensions were shown to depend on their force and range of action. The strongest tensions were short-lived and, besides, limited in space. Weak tensions were long-lived and spread all over the brain. In all cases of dissections the cells inducing tangential tensions reacted in the same way: by elongation of cell bodies along the normals to the brain layer. It is suggested that the tendency of cell elongation can cause the tangential tension of the layer. It was found that the partial removal of tensions enhances the curvatures of brain layers. The cells reacted to the tension removal in accordance with their position in the layer. If the cells are located in the grooves, they are shortened. If the cells are outside the grooves, they are elongated. It was found that after the tension was removed the nuclei migrated along the cell bodies. The migration of the nuclei depends on the direction of the layer flexure. The nuclei always migrated to the external surface of evagination or to the internal surface of flexure. It is suggested that the tangential tensions stabilize the changes in the brain shape. 相似文献
4.
V B Savel'ev 《Biofizika》1986,31(6):1027-1032
Mechanical characteristics and low-angle equatorial X-ray patterns from frog sartorius muscle passing into iodoacetate rigor under isometric conditions at temperatures 2 degrees-25 degrees C were studied. It is ascertained that during the rigor tension development at all the temperatures Z-reflection intensity increases and those of the (10), (11), (20), (21) and (30) reflections decrease. The last three reflections disappear then still in the phase of the rigor tension development. It is found that the sarcomere lengths remain not always invariable, especially at high temperatures, when the muscle passes into rigor, and can both decrease and increase in the sample place which is investigated by means of X-ray diffraction method. It is shown that the decrease of the I10/I11 relation in some experiments at high temperatures is only due to the sarcomere length decrease. The merging time of the Z and (11) reflections depends both on the temperature and on the sarcomere length change. Thus essential changes correlated with the rigor tension development, and resulted in the Z-reflection intensity increase take place in tetragonal lattice of Z-band and in the I-band region located near Z-band. In A-band the hexagonal lattice order change for the worse is marked only. It is proposed that the mechanism of the rigor tension development differs from that of tension development in ordinary contraction of the skeletal muscle. 相似文献
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Anonymous nuclear DNA markers in the American oyster and their implications for the heterozygote deficiency phenomenon in marine bivalves 总被引:4,自引:0,他引:4
A puzzling population-genetic phenomenon widely reported in allozyme
surveys of marine bivalves is the occurrence of heterozygote deficits
relative to Hardy-Weinberg expectations. Possible explanations for this
pattern are categorized with respect to whether the effects should be
confined to protein-level assays or are genomically pervasive and expected
to be registered in both protein- and DNA-level assays. Anonymous nuclear
DNA markers from the American oyster were employed to reexamine the
phenomenon. In assays based on the polymerase chain reaction (PCR), two
DNA-level processes were encountered that can lead to artifactual genotypic
scorings: (a) differential amplification of alleles at a target locus and
(b) amplification from multiple paralogous loci. We describe symptoms of
these complications and prescribe methods that should generally help to
ameliorate them. When artifactual scorings at two anonymous DNA loci in the
American oyster were corrected, Hardy-Weinberg deviations registered in
preliminary population assays decreased to nonsignificant values.
Implications of these findings for the heterozygote-deficit phenomenon in
marine bivalves, and for the general development and use of PCR-based
assays, are discussed.
相似文献
7.
Basolateral plasma membrane localization of ouabain-sensitive sodium transport sites in the secretory epithelium of the avian salt gland 下载免费PDF全文
The distribution of Na+ pump sites (Na+-K+-ATPase) in the secretory epithelium of the avian salt gland was demonstrated by freeze-dry autoradiographic analysis of [(3)H] ouabain binding sites. Kinetic studies indicated that near saturation of tissue binding sites occurred when slices of salt glands from salt-stressed ducks were exposed to 2.2 μM ouabain (containing 5 μCi/ml [(3)H]ouabain) for 90 min. Washing with label-free Ringer's solution for 90 min extracted only 10% of the inhibitor, an amount which corresponded to ouabain present in the tissue spaces labeled by [(14)C]insulin. Increasing the KCl concentration of the incubation medium reduced the rate of ouabain binding but not the maximal amount bound. In contrast to the low level of ouabain binding to salt glands of ducks maintained on a freshwater regimen, exposure to a salt water diet led to a more than threefold increase in binding within 9-11 days. This increase paralleled the similar increment in Na+-K+-ATPase activity described previously. [(3)H]ouabain binding sites were localized autoradiographically to the folded basolateral plasma membrane of the principal secretory cells. The luminal surfaces of these cells were unlabeled. Mitotically active peripheral cells were also unlabeled. The cell-specific pattern of [(3)H]ouabain binding to principal secretory cells and the membrane-specific localization of binding sites to the nonluminal surfaces of these cells were identical to the distribution of Na+-K+-ATPase as reflected by the cytochemical localization of ouabain-sensitive and K+-dependent nitrophenyl phosphatase activity. The relationship between the nonluminal localization of Na+-K+-ATPase and the possible role of the enzyme n NaCl secretion is considered in the light of physiological data on electrolyte transport in salt glands and other secretory epithelia. 相似文献
8.
Etherification of butanol by acetic anhydride in butanol-butyl acetate mixtures containing 0.09 to 3 per cent water was investigated. A method for processing the butanol-butyl acetate mixtures with the weight part of butanol up to 16 per cent by etherification of the latter with acetic anhydride was developed, the yield being 96 to 97 per cent and the weight part being at least 97.5 per cent. On the basis of the estimate of the raw material use for regeneration of butyl acetate from the butanol-butyl acetate solutions by etherification of butanol with acetic anhydride, the technical and economic advantages of the processing of such solutions by the described method were shown. 相似文献
9.
旨在利用CRISPR/Cas9技术构建敲除花生四烯5-脂氧合酶基因(Arachidonate 5-lipoxygenase gene,ALOX5)的重组质粒。设计合成3对靶向敲除ALOX5第六外显子的sgRNA,将其分别插入到CRISPR/Cas9质粒骨架pX458载体中,转化感受态大肠杆菌DH5α后挑取克隆,通过测序评估重组质粒是否构建成功。将构建好的重组质粒转染293T细胞,在荧光显微镜下观察转染效果,挑取转染成功的细胞,用试剂盒提取转染细胞基因组DNA,PCR扩增含敲除位点的DNA片段,用测序技术获得核苷酸序列,用DNAStar软件分析转染细胞中ALOX5基因敲除情况。测序结果表明2对双链sgRNA寡核苷酸已插入质粒,且序列正确,靶向ALOX5基因的重组质粒pX458-sgRNAs-ALOX5构建成功。其在293T细胞中的转染效率约为50%,用一代测序法未检测到sgRNAs的切割效果。初步表明利用CRISPR/Cas9技术成功构建靶向ALOX5基因的重组质粒pX458-sgRNAs-ALOX5。 相似文献
10.