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1.
A E Aleksandrova N M Shcherbakova N V Zabolotnykh R A Shchegoleva 《Problemy tuberkuleza》1991,(8):68-71
The results of a study of a new synthetic drug dimephosphon used as a pathogenetic means in the treatment of experimental tuberculosis are presented. Dimephosphon was found to be responsible for both the in vivo and in vitro decrease of the degree of MBT resistance to rifampicin. The findings of macroscopic, histologic and bacteriologic examinations demonstrated a significant increase in the effectiveness of antituberculous therapy. Dimephosphon monotherapy in mice elicited manifested stimulation of peritoneal macrophages: increase in O2- production, and decline in extracellular 5-nucleotidase activity. Nemolysine-synthetic cellular splenic activity in mice rose essentially. No direct stimulating influence of dimephosphon on functional macrophage activity in vitro was found. 相似文献
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G. N. Pershin L. I. Shcherbakova 《Bulletin of experimental biology and medicine》1957,44(9):1096-1099
Summary The effect of chemotherapeutic preparations on the synthesis of peptide bonds was studied.The reaction of synthesis of para-aminohippuric acid (PAHA) in sections of a rat's liver from para-aminobenzoic acid (PABA) and glycine was used. This method was described by P. P. Cohen and R. W. Gilwery. It was established that antituberculous chemotherapeutic preparation Tubazid, Ftivazid, Tibon, and streptomycm do not disturb biosynthesis of para-aminohippuric acid by liver slices. Penicillin, chloramphenicol. syntomycin, dextromycetin and chlortetracyclin in low concentrations, which correspond to therapeutic, have no effect on the above reactions of biosynthesis. In high concentrations these drugs suppress this reaction up to complete inhibition. Depression of reaction of biosynthesis of PAHA by chloramphenicol and its stereolsomers, penicillin, and chlortetracyclin may be explained by similarity of the chemical structure of the depressing substances with the products of this reaction.Presented by V. V. Zakusov, Member AMS USSR 相似文献
6.
For assessment of the incidence and characteristics of urination disorders and erectile dysfunction after radical surgical treatment of anorectal congenital defects in children, 60 patients (12 girls, 48 boys) without urination disorders before operation, who have undergone 1-4 proctoplasties were examined. Their was Hirschsprung's disease in 20 patients, anorectal atresia in 40 patients. Iatrogenic urination disorders and erectile dysfunction were revealed in 38 (63.3%) patients, majority of them (24) underwent repeated proctoplasty. The main urination disorders were urinary incontinence (30 patients), infravesical obstruction (10), hyporeflexion of urinary bladder. Erectile dysfunction after operation was in 11 (34.4%) patients from 32. The combination of disorders was revealed in 17 (44.7%) patients. Primary radical operations in children with anorectal defects often cause iatrogenic urination disorders and erectile dysfunction. The number of complications increases progressively after repeated proctoplasty. It is necessary to improve the treatment and the methods of surgical correction bearing in mind the risk of iatrogenic disorders of genitourinary apparatus. 相似文献
7.
N. S. Shcherbakova A. N. Chikaev L. I. Karpenko A. A. Il’ichev 《Molecular Genetics, Microbiology and Virology》2012,27(1):22-27
The effect of biotinylation of monoclonal antibodies (MAbs) on the yield and repertoire of peptides selected by biopanning
is discussed in the present study. A comparative analysis of peptides selected from a phage library using the biotinylated
and nonbiotinylated MAb 2F5 was performed. The yield of the peptides homologous to the native epitope was observed to be 1.7 times higher for the biotinylated
antibodies, whereas the use of the nonbiotinylated antibodies in the enzyme-linked immunoassay (ELISA) resulted in a greater
binding capacity of the selected phages with MAb 2F5. It is notable that the phages, displaying peptides that have a fouror five-amino-acid sequence similarity with the native
epitope, demonstrate the highest binding affinity to the antibodies. The phages exposing peptides with three-amino-acid sequence
similarity exhibit various binding affinities. In summary, the results have revealed that a rational biopanning protocol should
be chosen according to the aim of each particular study. 相似文献
8.
Julia Steinbach Henry Holmstrand Kseniia Shcherbakova Denis Kosmach Volker Brüchert Natalia Shakhova Anatoly Salyuk Clia J. Sapart Denis Chernykh Riko Noormets Igor Semiletov
rjan Gustafsson 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(10)
The East Siberian Arctic Shelf holds large amounts of inundated carbon and methane (CH4). Holocene warming by overlying seawater, recently fortified by anthropogenic warming, has caused thawing of the underlying subsea permafrost. Despite extensive observations of elevated seawater CH4 in the past decades, relative contributions from different subsea compartments such as early diagenesis, subsea permafrost, methane hydrates, and underlying thermogenic/ free gas to these methane releases remain elusive. Dissolved methane concentrations observed in the Laptev Sea ranged from 3 to 1,500 nM (median 151 nM; oversaturation by ∼3,800%). Methane stable isotopic composition showed strong vertical and horizontal gradients with source signatures for two seepage areas of δ13C-CH4 = (−42.6 ± 0.5)/(−55.0 ± 0.5) ‰ and δD-CH4 = (−136.8 ± 8.0)/(−158.1 ± 5.5) ‰, suggesting a thermogenic/natural gas source. Increasingly enriched δ13C-CH4 and δD-CH4 at distance from the seeps indicated methane oxidation. The Δ14C-CH4 signal was strongly depleted (i.e., old) near the seeps (−993 ± 19/−1050 ± 89‰). Hence, all three isotope systems are consistent with methane release from an old, deep, and likely thermogenic pool to the outer Laptev Sea. This knowledge of what subsea sources are contributing to the observed methane release is a prerequisite to predictions on how these emissions will increase over coming decades and centuries.The East Siberian Arctic Shelf (ESAS) is the world’s largest and shallowest shelf sea system, formed through inundation of northeast Siberia during sea level transgression in the early Holocene. The ESAS holds substantial but poorly constrained amounts of organic carbon and methane (CH4). These carbon/methane stores are contained in unknown partitions as gas hydrates, unfrozen sediment, subsea permafrost, gas pockets within and below the subsea permafrost, and as underlying thermogenic gas (1–3). Methane release to the atmosphere from these compartments could potentially have significant effects on the global climate (4, 5), yet there are large uncertainties regarding the size and the vulnerability toward remobilization of these inaccessible and elusive subsea carbon/methane pools. Conceptual development and modeling have predicted that warming of the ESAS system by a combination of geothermal heat and climate-driven Holocene heat flux from overlying seawater, recently further enhanced by Anthropocene warming, may lead to thawing of subsea permafrost (6, 7). Subsea permafrost drilling in the Laptev Sea, in part at the same sites as 30 y ago, has recently confirmed that the subsea permafrost has indeed come near the point of thawing (8). In addition to mobilization of the carbon/methane stored within the subsea permafrost, its degradation can also lead to the formation of pathways for gaseous methane from underlying reservoirs, allowing further methane release to the overlying water column (3, 9).Near-annual ship-based expeditions to the ESAS over the past two decades have documented widespread seep locations with extensive methane releases to the water column (3, 10). Methane levels are often found to be 10 to 100 times higher than the atmospheric equilibrium and are particularly elevated in areas of strong ebullition from subsea gas seeps (“methane hotspots”). Similarly, elevated dissolved methane concentrations in bottom waters appear to be spatially related to the thermal state of subsea permafrost as deduced from modeling results and/or geophysical surveys (7, 9). Currently, we lack critical knowledge on the quantitative or even relative contributions of the different subsea pools to the observed methane release, a prerequisite for robust predictions on how these releases will develop. An important distinction needs to be made between pools that release methane gradually, such as methane produced microbially in shallow sediments during early diagenesis or in thawing subsea permafrost, versus pools with preformed methane that may release more abruptly once pathways are available, such as from disintegrating methane hydrates and pools of thermogenic (natural) gas below the subsea permafrost. Multidimensional isotope analysis offers a useful means to disentangle the relative importance of these different subsea sources of methane to the ESAS: Stable isotope data (δ13C-CH4 and δD-CH4) provide useful information on methane formation and removal pathways, and the radiocarbon content of methane (Δ14C-CH4) helps to determine the age and methane source reservoir (see SI Appendix, text S1 for details on these isotope systematics and typical isotopic signatures for the ESAS subsea system).Here, we present triple-isotope–based source apportionment of methane conducted as part of the Swedish–Russian–US investigation of carbon–climate–cryosphere interactions in the East Siberian Arctic Ocean (SWERUS-C3) program. To this end, the distribution of dissolved methane, its stable carbon and hydrogen isotope composition, as well as natural radiocarbon abundance signature, were investigated with a focus on the isotopic fingerprint of methane escaping the seabed to pinpoint the subsea sources of elevated methane in the outer Laptev Sea. 相似文献
9.
Lineage-restricted regulation of the murine SCL/TAL-1 promoter 总被引:10,自引:2,他引:10
Bockamp EO; McLaughlin F; Murrell AM; Gottgens B; Robb L; Begley CG; Green AR 《Blood》1995,86(4):1502-1514
10.
PO Ajiboye OA Abiodun MF Tunde-Ayinmode OIN Buhari EO Sanya KW Wahab 《African health sciences》2013,13(3):624-631