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531.
532.
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   
533.
Experiments in a number of biological models showed that the cultures of E. coli isolated from the urine of children with pyelonephritis had a varied spectrum of pathogenic properties. Histologically confirmed pyelonephritis induced by intravenous infection in CBA mice, treated with 5% glucose by the method of Montgomerie et al., correlated with the bacterial adhesiveness to the epithelium and the interference with capillary permeability, registered in experiments on the pulmonary model with Evans blue used for control. The criterion for the development of pyelonephritis in mice, which was based, in the opinion of Mintogemerie et al., on the positive results, indicating the presence of the infecting agent in the culture obtained by inoculation with the samples of urine and kidney tissue, was found to be insufficient, as only 28 out of 45 cultures of E. coli isolated from the kidneys coincided with histologically confirmed cases of pyelonephritis.  相似文献   
534.
535.
The use of the serological method (the indirect fluorescent antibody test) for the examination of 255 persons coming in contact with patients having hemorrhagic fever with the renal syndrome (HFRS) in the foci of this infection where outbreaks of group infection had been registered made it possible to detect mild, unclear and asymptomatic forms of HFRS in 17.7-20.9% of cases. The simultaneous titration of 317 serum samples with two antigens revealed that HFRS virus of serotype 1, similar to strain Hantaan from Korea, may cause, besides the classical forms of the disease, the development of mild and asymptomatic forms of this infection.  相似文献   
536.
Night melatonin concentration in blood serum has been studied in intact Wistar young pubertal and old male rats in different seasons--in winter (light regime: 9 hours light, 15 hours dark) and in summer (light regime: 15 hours light, 9 hours dark). It is shown that night peak of this index depends both on the age and season. Serum melatonin level decreases at midnight in old male rats as against the young ones. This decrease is redoubled under conditions of increase in light day duration. The importance of seasonal peculiarities of night peak melatonin formation in the mechanism metabolopathy in aging is under discussion.  相似文献   
537.
538.
The morphogenesis of individual organs and the whole organism occurs under the control of intercellular chemical signals mainly during the perinatal period of ontogenesis in rodents. In this study, we tested our hypothesis that the biologically active concentration of noradrenaline (NA) in blood in perinatal ontogenesis of rats is maintained due to humoral interaction between its central and peripheral sources based on their plasticity. As one of the mechanisms of plasticity, we examined changes in the secretory activity (spontaneous and stimulated release of NA) of NA-producing organs under deficiency of its synthesis in the brain. The destruction of NA-ergic neurons was provoked by administration of a hybrid molecular complex–antibodies against dopamine-β-hydroxylase associated with the cytotoxin saporin–into the lateral cerebral ventricles of neonatal rats. We found that 72 h after the inhibition of NA synthesis in the brain, its spontaneous release from hypothalamus increased, which was most likely due to a compensatory increase of NA secretion from surviving neurons and can be considered as one of the mechanisms of neuroplasticity aimed at the maintenance of its physiological concentration in peripheral blood. Noradrenaline secretion from peripheral sources (adrenal glands and the organ of Zuckerkandl) also showed a compensatory increase in this model. Thus, during the critical period of morphogenesis, the brain is integrated into the system of NA-producing organs and participates in their reciprocal humoral regulation as manifested in compensatory enhancement of NA secretion in each of the studied sources of NA under specific inhibition of NA production in the brain.  相似文献   
539.
The purified preparations of Klebsiella bacteriophages, viz. the monovalent preparation of K. pneumoniae bacteriophage and the polyvalent bacteriophage preparation for the treatment of infections caused by K. ozaenae, K. rhinoscleromatis scleromatis and K. pneumoniae sensu lato, have been obtained. The bacteriophage preparations have proved to be nontoxic and safe for laboratory animals after the intraperitoneal injection of these preparations followed by the pathomorphological study of the internal organs of the animals. The clinical study of the newly developed bacteriophage preparations in the course of the treatment of purulent inflammatory diseases in 109 patients has revealed that the preparations are not reactogenic and exhibit sufficient effectiveness in the therapy of ozena, rhinoscleroma and Klebsiella infections with different localization of the infectious process.  相似文献   
540.
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