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71.
To solve the problem of unfavorable sanitary and epidemiological situation in diseases of respiratory organs in one of the organized groups in the Moscow region, a preparation prepared from a group of curative vaccines, IRS 19, was used. For controlling the effectiveness of its prophylactic action two groups of 250 persons were formed. As a result, morbidity rate in respiratory diseases decreased 2.5-3 times. In 1.5 months after the use of the preparation was started the coefficient of protection against the whole group of diseases of respiratory organs was 70%.  相似文献   
72.
The frequency of chromosome damage was studied in the carriers of virus of the hemorrhagic fever with renal syndrome (Puumala virus) and in noninfected animals from two laboratory colonies and two natural populations of bank vole. In the laboratory colony, where Puumala virus persisted for three years, multiaberrant ("rogue") cells were found in the bone marrow; the mean frequencies of both structural and numeral chromosome abnormalities were significantly enhanced. In the other laboratory colony, no Puumala virus was detected during all 30 years of its existence, but the mean frequencies of structural chromosome damage were increased to the same degree probably due to the prolonged breeding under laboratory conditions, which resulted in suppression of immunity and DNA repair. The voles from the natural populations were more resistant to the clastogenic viral effect, but they also had multiaberrant cells which served as indicators of viral infection. The data obtained support the hypothesis that viral infections increase mutation rate, contributing thereby to the evolution process.  相似文献   
73.
The results of studies carried out with the use of the unified, specially developed methods in eight regions of the USSR are generalized. Basing on the analysis of the results, the leading role of serogroup A meningococci in the rise of morbidity is emphasized, the relation of the morbidity level to the serogroup composition of meningococci circulating among healthy population is revealed, the necessity of carrying out selective bacteriological surveys with a view to establish the serogroups of meningococci circulating among the population is shown. The expedient criteria to be used in the system of epidemiological surveillance of meningococcal infection are presented.  相似文献   
74.
75.
Stress caused by acute cysteamine duodenal ulcer was induced in Wistar male rats. All the endogenous opioides under study were involved in the stress-reaction mechanism. Protective dalargin (synthetic enkephalin analogue) administration revealed a tendency towards normalization of endorphin, L-enkephalin and ACTH blood levels.  相似文献   
76.
The literary and experimental data obtained by the authors concerning the ability of various microorganisms to synthesize exoproteases lysing the thrombi of human blood are presented in the article. Various methods of enhancing the thrombolytic activity of microorganisms cultures, the properties of some isolated and purified preparations, methods of enlarging the specificity of the enzymes to fibrin and of reduction of their toxicity are considered.  相似文献   
77.
78.
The possibility of using, on principle, the reaction of radial hemolysis for the determination of antibodies to meningococci has been shown. The sensitivity and resolution of this method has been found to depend on the dose of the antigen used for the sensitization of erythrocytes, on the concentration of the erythrocyte suspension introduced into the gel and on the amount of complement. The optimum conditions for the reaction of optimum hemolysis, used for the determination of antibodies to serogroup A Neisseria meningitidis polysaccharide, have been established: the sensitizing dose of the antigen must be 50-100 micrograms/ml, the concentration of sensitized erythrocytes 25%, and the amount of complement 20-40 HU.  相似文献   
79.
The studies demonstrated the immunological and epidemiological effectiveness of a single injection of adsorbed diphtheria-tetanus toxoid with reduced antigen content for adults: intense antidiphtheria immunity in 92.3% of the vaccinees 1-3 months and in 94.5% of the vaccinees 1 year after the injection. This immunity remained sufficiently intense for 3 years (the term of observation). The geometric mean of antitoxic titers was 0.84 I. U./ml. The highest intensity of immunity appearing after the injection was observed in persons aged 18-20 years who showed the highest antitoxic titers (exceeding 0.5 I. U./ml) in 100% of cases, the lowest intensity was registered in the age group of 30-39 years; in 14.2% of these vaccinees antitoxic titers were below the protective level. In other age groups (40-49 years, 50 years and over) the intensity of immunity was high. The geometric mean of the titers of diphtheria antitoxin were 1.2 I. U./ml and 2.1 I. U./ml respectively. In none of the foci under study the spread of the manifest forms of the disease was observed.  相似文献   
80.
Frankia strains are nitrogen-fixing soil actinobacteria that can form root symbioses with actinorhizal plants. Phylogenetically, symbiotic frankiae can be divided into three clusters, and this division also corresponds to host specificity groups. The strains of cluster II which form symbioses with actinorhizal Rosales and Cucurbitales, thus displaying a broad host range, show suprisingly low genetic diversity and to date can not be cultured. The genome of the first representative of this cluster, Candidatus Frankia datiscae Dg1 (Dg1), a microsymbiont of Datisca glomerata, was recently sequenced. A phylogenetic analysis of 50 different housekeeping genes of Dg1 and three published Frankia genomes showed that cluster II is basal among the symbiotic Frankia clusters. Detailed analysis showed that nodules of D. glomerata, independent of the origin of the inoculum, contain several closely related cluster II Frankia operational taxonomic units. Actinorhizal plants and legumes both belong to the nitrogen-fixing plant clade, and bacterial signaling in both groups involves the common symbiotic pathway also used by arbuscular mycorrhizal fungi. However, so far, no molecules resembling rhizobial Nod factors could be isolated from Frankia cultures. Alone among Frankia genomes available to date, the genome of Dg1 contains the canonical nod genes nodA, nodB and nodC known from rhizobia, and these genes are arranged in two operons which are expressed in D. glomerata nodules. Furthermore, Frankia Dg1 nodC was able to partially complement a Rhizobium leguminosarum A34 nodC::Tn5 mutant. Phylogenetic analysis showed that Dg1 Nod proteins are positioned at the root of both α- and β-rhizobial NodABC proteins. NodA-like acyl transferases were found across the phylum Actinobacteria, but among Proteobacteria only in nodulators. Taken together, our evidence indicates an Actinobacterial origin of rhizobial Nod factors.  相似文献   
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