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521.
L. P. Sashchenko E. A. Dukhanina T. I. Luk’yanova O. D. Kabanova E. A. Romanova Yu. V. Shatalov D. V. Yashin N. V. Gnuchev 《Molecular Biology》2000,34(5):691-695
It has been shown that lysis of tumor target cells caused by lymphokine-activated killers is possible both upon a direct contact
and in the presence of isolated nongranular cytotoxic proteins. The contact of cytolytic lymphocytes with K-562 cells leads
to Fas L activation on the lymphocyte membrane and secretion of a broad spectrum of soluble cytotoxic proteins immunologically
related to Tag 7 described earlier. These proteins can form inactive complexes, which are reactivated upon heating and addition
of ATP. The proteins induced discrete cytolytic processes in tumor cells, differing in the rate of cytolysis and the mechanism
of the apoptotic signal transduction. Fast processes (revealed in 3 h) mediated by caspases, and slow ones (in 24 h) with
the supposed involvement of mitochondria were detected. A scheme for the lymphokine-activated killer interaction with target
tumor cells is proposed. 相似文献
522.
V M Bondarenko A L Iablochkov Iu M Romanova V G Petrovskaia 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1988,(3):28-32
Electrophoretic study of the profile of plasmid DNA in agarose gel has shown the presence of a plasmid with a molecular weight of 55-60 MD in K. pneumoniae strains possessing antilysozyme activity. Plasmid pAlz60 of K. pneumoniae 22-110, isolated from the blood of a septicemia patient, is a fi- type conjugative plasmid. This plasmid is transferred to recipient strains of different species of enterobacteria with a frequency of 1 X 10(-5) to 1 X 10(-7). Simultaneously with the transfer of the plasmid, recipient cells inherit the antilysozyme markers and resistance to a number of drugs. The discovered plasmid has one restriction site for each of endonucleases EcoRI and XhoI and 16-20 sites for restrictases KpNI, BglII and Hind III. 相似文献
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T. A. Shelkovenko S. A. Pikuz A. R. Mingaleev A. V. Agafonov V. M. Romanova A. E. Ter-Oganes’yan S. I. Tkachenko I. C. Blesener M. D. Mitchell K. M. Chandler B. R. Kusse D. A. Hammer 《Plasma Physics Reports》2008,34(9):754-770
The generation of accelerated electrons in the X-pinch minidiode is studied experimentally. It is well known that the explosion of an X-pinch consisting of two or more wires is accompanied by the formation of a minidiode, in which electrons are accelerated. The subsequent slowing down of electrons in the products of wire explosion causes the generation of hard X-ray (HXR) emission with photon energies higher than 10 keV. In this work, the spatial and temporal characteristics of X-pinch HXR emission are studied, the specific features of HXR generation are discussed, and the capability of applying this radiation to point-projection X-ray imaging of various plasma and biological objects is considered. The parameters of the electron beam produced in the X-pinch are measured using a Faraday cup and X-ray diagnostics. The experiments were performed with the XP generator (550 kA, 100 ns) at Cornell University (United States) and the BIN generator (270 kA, 150 ns) at the Lebedev Physical Institute (Russia). 相似文献
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The fractional composition of extracellular lipids extracted with hexane and ethanol was studied in the yeast Rhodotorula glutinis 35 by thin-layer chromatography. The two extracts of extracellular lipids were found to be similar in composition though differing in the quantitative content of individual fractions. The fractional composition of extracellular lipids differed from that of intracellular lipids. The peculiarity of the fractional composition of extracellular lipids can be accounted for by the specificity of its fatty acid and alcohol composition. 相似文献
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Ascaris lumbricoides: detecting its metabolites in the urine of infected people using gas-liquid chromatography 总被引:1,自引:0,他引:1
Substances dissolved in the urine of people infected with Ascaris lumbricoides were extracted and detected by gas-liquid chromatography. The ratios of the areas of the peaks produced by two substances extracted from urine to the area of the peak of solvent were found to be significantly correlated with the worm burden. A chemical analysis of the predominant substance by infrared spectrophotometry and proton magnetic resonance spectrometry indicated that it was 2-methyl-butyramide. The chemical properties of the other substance indicated that it was 2-methyl-valeramide. These substances are likely to be derivatives of two acids known to be end products of the carbohydrate metabolism of Ascaris. 相似文献