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1.
V A Frolov G Mall P Rieger Kh Derks Z Antoni 《Biulleten' eksperimental'no? biologii i meditsiny》1987,104(12):739-741
Intensive synthesis of collagen-like substance was revealed in the rabbit myocardium during experimental diphtheria intoxication. It was more marked in the right ventricle 24 hours after the injection of diphtheria toxin. Since similar changes (the substance was mainly formed around blood vessels) have been observed in other cases of toxic myocardial alterations (i.e. ethanol intoxication, injection of pharmacological agents, etc.), it can be assumed that it is a standard protective reaction of the altered heart to the penetration of toxic agents from the blood into the myocardial tissue. 相似文献
2.
Experiments in mice have demonstrated that in the presence of influenza infection the suppressing effect of virulent shigellae on the secondary humoral and cell-mediated immune response is enhanced. Under such conditions avirulent shigellae can also show suppressing effect which is usually absent in these organisms. 相似文献
3.
A F Frolov V E Rychnev V M Frolov M A Bala 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1985,(11):93-96
The dynamics of circulating immune complexes (CIC) in comparison with the level of SH-groups of serum deproteinate and other characteristics of cell-mediated and humoral immunity (the reaction of the inhibition of antibodies, the levels of T-cells and their main subpopulations) was studied in 103 erysipelas patients and in 46 persons having had the disease at the acute period of this infection and at the periods between relapses. The elevated levels of CIC and SH-groups of serum deproteinate were found to be directly correlated with the inhibition index. The study showed that, as a rule, in patients with the elevated level of CIC the frequently relapsing form of erysipelas, accompanied by the formation of relative hypersuppressor-type secondary immunodeficiency and by a decrease in the functional activity of dermal macrophages, was observed. 相似文献
4.
A A Frolov 《Biofizika》1989,34(2):280-286
Calculations are made of information parameters of neuron nets with binary plastic synapses of Hebb and Albus which are able to form and produce neuron assemblies. It has been shown that for such neuron nets Hebb synapses are more effective than Albus synapses. 相似文献
5.
Informational losses in neuronal nets(NN) with plastic elements were estimated. These losses are related with 1) transition from "complicated" decoding when from the modification state of such elements information of the whole set of recorded elements is extracted to "simple" decoding natural of NN functioning when information is extracted independently for individual events; 2) uncertainty concerning NN structure, if at decoding in one of the modification states the neuron reactivity totally or the weight of plastic synapse equals zero. After the transition from complicated to simple decoding these losses for gradual plasticity are so great that NN with such plasticity has no advantages in informational capacity as compared to the binary one. These losses are absent for plasticity of Olbus type. They are relatively high for neuronal plasticity of Hebb type. For Hebb synapses their value essentially depends on the net parameters. 相似文献
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7.
A F Frolov G S Skripchenko A M Shcherbinskaya A G Vlasova T M Rybakova 《Journal of hygiene, epidemiology, microbiology, and immunology》1984,29(3):303-309
The authors studied the peculiarities of the course of experimental influenza infection induced by the administration of highly and poorly immunogenic strains of influenza virus to mice. Influenza viruses with varying immunogenic activity were obtained from the vaccine strain A/Victoria/35/72/50 (H3N2) by immunoselection modelling the process of natural selection. The administration of strains with high and poor immunogenicity to mice of the F1 (CBA X C57B1) line led to the development of acute influenza infection accompanied by reproduction of viruses in the tissue of the lungs and other internal organs. The poorly immunogenic strain 5/II-Victoria, unlike the initial virus A/Victoria/35 and its highly immunogenic variant 2/I-Victoria, is able to circulate for a long time in the organism of the infected animal causing development of chronic inflammatory processes and stimulating the formation of neoplasms. Immunogenicity is thus one of the factors determining the character of the course of experimental influenza infection. A conclusion was drawn concerning the epidemiological and aetiological importance of viruses with reduced immunogenicity and their role in the evolution of influenza virus. It is presumed that reduced immunogenicity is one of the adaptation mechanisms of aggression permitting the population of influenza virus to escape control by specific humoral immunity. 相似文献
8.
A stochastic memory model based on the net of excitatory and inhibitory neurons is considered. Its learning ability is due to a decrease of the reactivity of inhibitory elements. Information capacity of such neuron net was estimated in relation to its structure parameters. It has been shown that in the definite range of their change the information capacity of the net under consideration significantly exceeds that of the neuron net with the memory based on the plasticity of excitatory elements. 相似文献
9.
10.
Fatty acid composition of lipopolysaccharides of the strains of different species of Yersinia 总被引:1,自引:0,他引:1
A F Frolov N M Ruban Z P Vasyurenko 《Journal of hygiene, epidemiology, microbiology, and immunology》1989,33(1):55-61
The fatty acid composition of lipopolysaccharides of the strains of Y. enterocolitica, Y. intermedia, Y. frederiksenii and Y. ruckeri studied during cultivation on meat-peptone agar is characterized by the predominance of 3-hydroxytetradecanoic and dodecanoic acids. Closely related to the mentioned bacteria is the strain of Y. kristensenii which is distinguished only by its higher level of hexadecanoic acid. The strains of Y. pseudotuberculosis and the vaccine strain of Y. pestis have a uniform fatty acid composition of lipopolysaccharides with predominance of 3-hydroxytetradecanoic acid. Their relatively low level of dodecanoic acid conditions the characteristic fatty acid spectrum of lipopolysaccharides which differs from that of the above mentioned group of Yersinia. The peculiarities of the fatty acid composition of lipopolysaccharides of both groups of Yersinia are preserved during growth on meat-peptone broth, but the increase in the level of hexadecanoic acid balances the differences between Y. kristensenii, the other Y. enterocolitica-like bacteria and Y. ruckeri. The obtained results confirm close relationship of Y. pseudotuberculosis and Y. pestis, and also of Y. enterocolitica and Y. enterocolitica-like bacteria, showing propinquity of Y. ruckeri to the latter. 相似文献