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101.
6-O-(3-Methoxycarbonylpropyl)- and 6-O-(3-carboxypropyl)oximes of 16 alpha,17 alpha-cyclohexanopregn-4-ene-3,6,20-trione labeled by tritium in position 1,2 were synthesized. When using homogenous catalysts, the molar radioactivity of the resulting preparations was 1.5-1.7 PBq/mol.  相似文献   
102.
Aza- and deazaanalogues of adenosine, including their 1-protonated forms (except for that of 1-deazaadenosine), were studied by computer computation to find a relationship between their molecular structures and substrate properties for the mammalian adenosine deaminase. The atomic charge distribution and maps of the electrostatic potential around their van der Waals molecular surface were calculated for these compounds using the ab initio STO-3G method. The conformational studies were carried out by the MM+ method of molecular mechanics. The mechanism that determines the substrate selectivity of mammalian adenosine deaminase is discussed. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2002, vol. 28, no. 4; see also http://www.maik.ru.  相似文献   
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It is discovered that chronic consumption of ethanol induced decrease of carboxypeptidase H activity in striatum by 27%; increase of carboxypeptidase M activity in hippocampus by 67% and decrease in cerebral hemispheres by 34%; phenylmethylsulfonyl fluoride-inhibited carboxypeptidase activity increase in hypothalamus by 141%, in striatum by 60% and in optic and lamina quadrigemina by 34%. The role of basic carboxypeptidases in mechanisms of ethanol influence on the peptidergic systems are discussed.  相似文献   
107.
The methodological aspects of the study of the microflora of the parietal mucous layer (parietal mucin) of the large intestine is discussed; the study is difficult because the mucin layer is thin closely associated with epithelium and the impossibility of the mechanical separation of this layer from the epithelium without damaging the latter is possible. The method of homogenization fails to determine of the composition of parietal mucin proper. Such possibility becomes real after the dissolution of mucin and obtaining the suspension of microbial cells. As experimentally shown in vitro, urea solution, reducing disulfide bonds, effectively depolymerized mucin and exhibited no antibacterial and cytolytic activity. With the use of urea treatment, microflora of parietal mucin of the large intestine was studied on 44 non-inbred mice. This newly developed method was shown to have higher resolution in comparison with the traditional one (homogenization). Some qualitative and quantitative characteristics of the microflora of parietal mucin were established. In the same group of mice the study of fecal microflora was made and compared with microflora of parietal mucin.  相似文献   
108.
Examination of children with different noninfectious diseases resulted in obtaining the data base on the state of health of 201 children belonging to the potential risk group of the development of secondary immunodeficiency. The children were subdivided into several groups which differed by the type of immune disturbances and accompanying metabolic shifts. The level of antibodies to one of the fragments of peptidoglycan-N-acetylmuramyldipeptide was compared with the character of changes in the immune system. Different titers of serum antibodies to peptidoglycan were found to correspond to different forms of immune disturbances. The study showed that from the group with the absence of definite signs of immunodeficiency to the group with the pronounced deficiency of T lymphocytes and monocytes expressing CD14 antigen changes in the immune system increased in parallel to a rise in the concentration of alpha 2-macroglobulin, the development of hypercholesterolemia and a decreased level of antibodies to peptidoglycan. Opportunistic microflora was seemingly an important factor in the formation of definite forms of disturbances of the immune system and accompanying metabolic shifts.  相似文献   
109.
Ninety-nine patients aged 16-52 years with disseminated atopic dermatitis at the remission were examined and treated. The patients were divided into 3 groups according to the method of therapy. Group 1 (28 patients aged 17-52 years, found to be sensitive to Dermatophagoides pteronyssinus and D. farinae) received, in addition to standard treatment, immunotherapy (oral hyposensitization with mite allergens) in combination with ointment containing retinopalmitate and methyluracil. Group 2 (39 patients aged 17-40 years) received standard treatment combined with the administration of placebo. Group 3 (32 patients aged 16-27 years) received only standard therapy. Groups 2 and 3 were used for comparison. The results of treatment were evaluated according to changes in the immune status of the patients and a complex of clinical characteristics. Essential improvement in clinical characteristics and the normalization of immunological parameters were registered in group 1, which proved that immunotherapy was effective and safe.  相似文献   
110.
The Acinetobacter calcoaceticus strain TM-31 has been isolated from a microbial assemblage of a pilot plant purifying waste water polluted with mineral oil. This strain is capable of efficient degradation of components of mineral oil (alkanes, isoalkanes, and alkyl residues of the naphthene and arene fraction. The strain bears stably inherited plasmids of sizes 120, 9, and 8 kb, which can be transferred into plasmid-free cells of the parental strain and into bacteria of the genus Pseudomonas and ensure the degradation of hexadecane and mineral oil.  相似文献   
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