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1.
A A Grinev E I Samokhvalov N A Petrov S K Vasilenko V P Iuferov 《Molekuliarnaia genetika, mikrobiologiia i virusologiia》1988,(9):43-45
The primary structure of hemagglutinin (HA) gene of Influenza virus A/USSR/90/77 (H1N1) variants after 3 and 11 passages has been determined. In the HA1 coding region of mice-adapted virus (11 passages) there are two amino acid substitutions: Thr 89----Ala and Asn 127----Asp. At the first stage of adaptation (3-rd passage) only a single mutation was detected: Asn 127----Asp. The adaptation is accompanied by the loss of specific carbohydrate attachment sites adjacent to the receptor-binding site located at HA1 subunit with a concomitant variation in antigenicity. 相似文献
2.
O G Ianovski? L A Zakharova A M Vasilenko 《Biulleten' eksperimental'no? biologii i meditsiny》1990,109(1):55-57
In addition to the immunostimulating activity, bone marrow mediators, myelopeptides (MP) show the dose-dependent effect on the development of pain sensitivity in mice. When injected in nanogram amounts, MP induce hyperalgesia and 3-9 fold higher production of antibodies against SREC. When injected in milligram amounts, they exhibit hypoalgesic effect and no influence on antibody production. Immunostimulating effect in MP (mol, mass less than 1 KD, fraction 3) is accompanied with hypoalgesia. Bone marrow factors of mol. masses 40-150 KD (fraction 1) eluted at Sephadex G-25 gel-filtration before MP enhance the pain sensitivity tHreshold and show a potent immunodepressive effect. Thus the bone marrow factors are capable of exhibiting the opposite effects on the immune system in the pain control system that evidences the tight interrelation between these systems. 相似文献
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V G Galaktionov D V Skatov R N Vasilenko 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1991,(4):61-63
The dependence of the functional activity of the peritoneal macrophages of mice immunized with Francisella tularensis vaccine strain on the presence of T-cells in the culture has been studied. The elimination of "immune" macrophages and sensitized T-lymphocytes by means of anti-Thy-1-2-serum has been shown to lead to a sharp decrease in both ingestive and digestive functions of the phagocytic mononuclears of peritoneal exudate to the level of the activity of macrophages isolated from intact animals. 相似文献
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The authors own results on the variety of the genomic primary structures in human influenza A viruses participating in the epidemic process, including the atypical viruses. The comparative studies revealed new trends in the HA gene antigenic drift on the late stages and the PB1 gene shift. Modifications occurring in the primary structure of the influenza A viruses native genomes during laboratory treatment (adaptation to new hosts, vaccine preparation, egg passaging) have been analyzed. Sequencing of several types of "antigenic anachronisms" revealed the direct links between some of such viruses and the anthropogenic pollution of the biosphere by vaccine strains. Modifications in the HA genes of influenza A viruses during the persistent infection have also been studied. 相似文献
7.
The targeted flexor isometric force steps developed by a wrist and corresponding EMG activity of the flexor muscles were studied in healthy volunteers. In 82.3–97.5% of trials, the main component of the force trajectory (before the postcorrections of the force level) showed complex dynamics: several (from two to five)dF/dt peaks were observed at this section of the trajectory. The distribution of time intervals from the initiation of the force trajectory todF/dt peaks was polymodal in all cases. The mean interval between successivedF/dt peaks varied from 56.7 msec to 84.4 msec in different individuals (the average group value was 70.5 msec). All tested subjects exhibited amplitude modulation of integrated EMG at the section reflecting the force step development; the averaged interval between the successive first-order EMG peaks calculated for the group of five persons was 78.6 msec. Strict temporal correlation ofdF/dt peaks and EMG peaks was found (coefficient of correlation averaged 0.94). It is concluded that the motor command ensuring performance of isometric force step includes a cyclic component; this feature must be taken into account when mechanisms controlling such motor events are interpreted. The frequency of the component is near the upper limit of a normal tremor frequency band. At the same time, it is impossible to regard the cyclic component in the motor command as a result of simple superposition of tremor on the targeted force development because the cyclic component is clearly synchronized with the force step initiation.Neirofiziologiya/Neurophysiology, Vol. 25, No. 6, pp. 455–462, November–December, 1993. 相似文献
8.
The effect of surface active agents on the activity of Na, K-ATPase and on the direct medium 18O exchange in the membrane preparations of the guinea pig kidney has been studied. The medium 18O exchange was considered as a character of the K+-dependent stage in ATPase reaction. Low concentration of all the surface active agents were shown to stimulate, and high concentrations -- to inhibit both ATPase and medium 18O exchange. The relation between medium 18O exchange and Na,K-ATPase activity was found to be equal to 1.5 +/- 0.1. The treatment of preparations by activating amounts of the surface active agents resulted in lowering this relation up to 1.0 +/- 0.09 and 1.3 +/- 0.04 for DOC and triton X-100, correspondently, due to a stronger stimulation of ATPase activity than of medium 18O exchange. With the inhibiting amounts of triton X-100 and histone H2a, this relation did not change, but it decreased in the presence of equal amounts of DOC. 相似文献
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Venkateswaran A McFarlan SC Ghosal D Minton KW Vasilenko A Makarova K Wackett LP Daly MJ 《Applied and environmental microbiology》2000,66(6):2620-2626
Immense volumes of radioactive wastes, which were generated during nuclear weapons production, were disposed of directly in the ground during the Cold War, a period when national security priorities often surmounted concerns over the environment. The bacterium Deinococcus radiodurans is the most radiation-resistant organism known and is currently being engineered for remediation of the toxic metal and organic components of these environmental wastes. Understanding the biotic potential of D. radiodurans and its global physiological integrity in nutritionally restricted radioactive environments is important in development of this organism for in situ bioremediation. We have previously shown that D. radiodurans can grow on rich medium in the presence of continuous radiation (6,000 rads/h) without lethality. In this study we developed a chemically defined minimal medium that can be used to analyze growth of this organism in the presence and in the absence of continuous radiation; whereas cell growth was not affected in the absence of radiation, cells did not grow and were killed in the presence of continuous radiation. Under nutrient-limiting conditions, DNA repair was found to be limited by the metabolic capabilities of D. radiodurans and not by any nutritionally induced defect in genetic repair. The results of our growth studies and analysis of the complete D. radiodurans genomic sequence support the hypothesis that there are several defects in D. radiodurans global metabolic regulation that limit carbon, nitrogen, and DNA metabolism. We identified key nutritional constituents that restore growth of D. radiodurans in nutritionally limiting radioactive environments. 相似文献