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41.
The results of the determination of antibodies to lipopolysaccharide (LPS) in 270 patients with different forms of meningococcal infection and in 816 healthy persons by means of the passive hemagglutination test are presented. The role of antibodies to LPS in the formation of humoral immunity to meningococci in sick children and adults is shown. Different forms of meningococcal infection have been found to have their specific features of the accumulation of antibodies to LPS. As revealed, the time of the sanation of liquor and the level of antibodies to LPS are unrelated, which indicates that antibodies to LPS may play some role in the pathogenesis of meningococcal infection.  相似文献   
42.
The conditions for the microencapsulation of alpha-chymotrypsin into semi-permeable polycarbonate membranes are selected. The diameter of the microcapsules is 100-150 microns. The microencapsulation can be carried out at any value of pH. The effect of the diffusion in the hydrolysis of some esters by microcapsulated alpha-chymotrypsin was estimated. The thermostability of the microencapsulated enzyme was studied.  相似文献   
43.
We have studied the molecular nature of ade2 mutations induced by UV light and bifunctional acridine-mustard (BAM) in wild-type (RAD) and in excision-deficient (rad2) strains of the yeast, Saccharomyces cerevisiae. In the RAD strain, UV causes 45% GC → AT transitions among all mutations; in the rad2 strain this value is 77%. BAM was shown to be highly specific for frameshift mutagenesis: 60% frameshifts in the RAD strain, and as many as 84% frameshifts in the rad2 strain were induced. Therefore, the rad2 mutation affects the specificity of UV- and BAM-induced mutagenesis in yeast. Experimental data agree with the view that the majority of mutations in the RAD strain are induced by a prereplicative mechanism, whereas mutations in the RAD strain are induced by a prereplicative mechanism, whereas mutations in the rad2 strain are predominantly postreplicative events. Our results also suggest that: (1) cytosine-containing photoproducts are the substances responsible for major premutational damage to DNA; (2) a fraction of the mutations may arise in the course of excision repair of UV photoproducts.  相似文献   
44.
Two characteristics were determined in the sera of patients by means of radioimmunoassay (RIA) techniques: the RIA titer and the characteristic indicating the presence of highly avid antibodies in the serum. This investigation revealed that in the sera of patients with meningococcal infection of moderate severity the values of the RIA titer of IgM, IgG and IgA, as well as the values indicating the levels of highly avid IgM, IgG and IgA, increased as the infection progressed. In patients with the severe form of meningococcal infection the values of the RIA titer of IgA and IgA increased, while the RIA titer of IgG remained practically unchanged. No dynamic changes in the characteristics indicating the presence of highly avid antibodies in the serum were observed.  相似文献   
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46.
Russian Journal of Genetics - Association of the A66G SNP in the MTRR gene with dental caries was studied in children with congenital anomalies of the maxillofacial region (CA of MFR), i.e., with...  相似文献   
47.
The Su(Hw) insulator found in the gypsy retrotransposon is the most potent enhancer blocker in Drosophila melanogaster. However, two such insulators in tandem do not prevent enhancer-promoter communication, apparently because of their pairing interaction that results in mutual neutralization. Furthering our studies of the role of insulators in the control of gene expression, here we present a functional analysis of a large set of transgenic constructs with various arrangements of regulatory elements, including two or three insulators. We demonstrate that their interplay can have quite different outcomes depending on the order of and distance between elements. Thus, insulators can interact with each other over considerable distances, across interposed enhancers or promoters and coding sequences, whereby enhancer blocking may be attenuated, cancelled, or restored. Some inferences concerning the possible modes of insulator action are made from collating the new data and the relevant literature, with tentative schemes illustrating the regulatory situations in particular model constructs.  相似文献   
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Comparative analysis of the diagnostic value of different laboratory methods in the diagnosis of H. influenzae b (Hib) pneumonia in children (bacteriological method, latex agglutination, counter immunoelectrophoresis, the passive hemagglutination test and the enzyme immunoassay (EIA) was carried out. EIA proved to be the most informative method for the diagnosing Hib pneumonia. EIA makes it possible to detect specific Hib antigens in different clinical materials in 48.8% of cases, as well as high titers of antibodies to mis infective agent in 61.7% of cases. The authors propose the unified criteria of the laboratory diagnosis of Hib infection in children.  相似文献   
50.
The results of examination of 156 patients were used to consider whether radiation and endoscopic techniques might be used in the differential diagnosis of gastric ulcerations. The necessity of their complex use is shown. Evidence is provided for that the understanding of intramural changes at the site of ulceration should underlie the interpretation of visual changes in the gastric mucosa. An algorithm has been developed for the rational and effective use of radiation and endoscopic techniques in the differential diagnosis of gastric ulcerations. The algorithm is shown to be highly effective in the correct interpretation of the pattern of an identified ulceration (98.4% specificity). Ultrasound and computed tomographic semiotics of benign and malignant gastric ulcerations is presented.  相似文献   
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