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41.
There are six morphogenetic types of forest ground litter in the gradient of big grass-sphagnous-dead litter marsh birch forest: deeply degraded litter, half degraded litter, rhizomatous litter (coarsely degraded), peaty litter, turfy-formed litter, and turfy litter. The specificity of their biochemical transformations is caused by the accumulation of humic acids (HA), especially of the first fraction (HA-1), alongside the relatively steady background formation of fulvic acids. The C/N value suggests that the intensity of HA-1 formation is closely associated with the biological activity of the substrate. However, the indistinct difference of these parameters in the forestry-morphological types of litters limits their diagnostic reliability. Grouped biochemical types of litters, such as “soft” (half- and deeply degraded), “intermediate” (rhizomatous, peaty and turfy-formed), and “coarse” (mossy), are considerably discriminated by both the C/N ratio (20, 30, 40) and the level of HA-1 (14, 10, and 6%) respectively. 相似文献
42.
E. A. Kirilina T. B. Masternak M. A. Efremov O. Yu. Kamyshnikov 《Russian Journal of Bioorganic Chemistry》2013,39(5):516-521
The capacity of the bone marrow-derived myelopeptide-1 (MP-1) to affect in vivo and in vitro the functional activity of phagocytes of intact mice and mice treated with a cytostatic agent (cyclophosphane) has been studied. It was found that MP-1 produces a correcting effect on the functional activity of bone marrow and peripheral blood phagocytes. An optimal scheme of the injection of MP-1 to mice with the cyclophosphane-induced immunodeficiency was developed, which provides a maximum immunocorrecting action. MP-1 had the most pronounced effect on the quantitative characteristics and the functional activity of phagocytes of different localization when introduced prior to the cytostatic; under these conditions, the pep tide affects peripheral blood neutrophils. The results obtained enable one to consider MP-1 as a preparation protecting the peripheral blood phagocytes from the damaging action of cyclophosphane. 相似文献
43.
D. S. Pavlov A. E. Veselov V. V. Kostin D. A. Efremov M. A. Ruchiev S. B. Tuniev 《Journal of Ichthyology》2018,58(1):93-103
Conditions of reproduction and distribution of the Black Sea trout Salmo trutta labrax in the basin of the Mzymta River after Olympic objects′ construction are considered. In the main river channel of the Mzymta, the structure of spawning and nursery grounds are destroyed along 57 km from the river mouth. The total area of these grounds in the Mzymta basin is 572800 m2, and 49% of this area is situated above the dam of the Krasnopolyanskaya Power Plant and is inaccessible for spawners of the migratory form of the Black Sea trout listed in the Red Data Book of the Russian Federation. Consequently, natural reproduction of the migratory form discontinued. The resident form of trout still exists in the upper parts of the Mzymta and in 19 of its tributaries not affected by construction. On the 2.4-km-long stretch of the riverbed situated below the inflow of the Pslukh tributary, the substrate is in the process of natural restoration due to the descent of mudslides followed by washing of the substrate by the flow. The river is partially inhabited by trout individuals from habitats not affected by construction. 相似文献
44.
B. Markovska G.D. Efremov S. Vuk-Pavlović B. Benko S. Maričić 《Archives of biochemistry and biophysics》1975,171(1):337-342
Solvent-proton longitudinal magnetic relaxation rates as dependent on temperature were measured for human (H)/canine (C) valency hybrids of the type {αH(III)βC(II)}2 and {αC(II)βH(III)}2. The two metheme irons in the human methemoglobin chains induce quite different proton magnetic relaxation (pmr) rates reflecting a tighter β-heme-pocket compared to the α subunit. Both heme-pockets appear to be loosened in the presence of inositol hexaphosphate (IHP) although this allosteric effector binds only to the β chains, the binding assumed to be the same for canine as for human hemoglobin. The subunit nonequivalence is retained also in the T-quaternary state induced by IHP. In the species hybrids the pmr rates due to the metheme iron are sensitive to the valency (ligand) state, which was either CO or H2O in the partner half of the hybrid. All results show very clearly the interrelationship of the tertiary (protomer) structure with the quaternary (oligomer) structure in hemoglobin. 相似文献
45.
46.
Biljana Cepreganova Jerry B. Wilson Brooke B. Webber Biljana Kjovkareska Georgi D. Efremov Titus H. J. Huisman 《Biochemical genetics》1992,30(7-8):385-399
We have analyzed the hemoglobins of five individual trout from the Ohrid Lake (Salmo L. typicus) by electrophoretic methods, by reversed-phase high-performance liquid chromatography, and by limited structural analyses. The two major classes of hemoglobin are type I (35% of total) and type IV (65%). Type IV is the major oxygen-transporting hemoglobin; it consists of three types of chain (in about equal quantities) and three types of chain (one major and two minor types). Several structural differences have been observed between these three (IV) chains and between the three (IV) chains, suggesting a complex genetic system governing the synthesis of these proteins. Moreover, a few amino acid substitutions occur at positions involved in contacts between chains, which suggests that differences in oxygen affinity may exist between these various type IV hemoglobins. Type I hemoglobin is less complex because it contains one type of chain and two chains; the latter two differ in numerous positions, suggesting duplications of the (I)-globin gene. The and chains of type I hemoglobin differ considerably from the and chains of type IV hemoglobin, indicating the existence of (I)- and (I)-globin genes separate from the (IV)- and (IV)- globin genes.This study was supported in part by the Yugoslav-American Joint Funds, pp 812 (to G.D.E.), and by United States Public Health Service Research Grant HLB-05168 (to T.H.J.H.). 相似文献
47.
The detection of beta-globin gene mutations in beta-thalassemia using oligonucleotide probes and amplified DNA 总被引:2,自引:0,他引:2
J C Diaz-Chico K G Yang K Y Yang D G Efremov T A Stoming T H Huisman 《Biochimica et biophysica acta》1988,949(1):43-48
DNA amplification combined with the use of synthetic oligonucleotide probes has become an important tool in the identification of base substitutions. We report the use of this DNA amplification technique for the detection of mutations in beta-thalassemia. A series of oligonucleotide primers are synthesized which span the beta-globin gene; one primer is complementary to the coding strand and the other to the non-coding strand. The primers are chosen so that there is little homology with other DNA segments, especially the delta gene. Each set of primers spans an area of the gene between 100 and 300 bp, while the suspected mutation point is located between these two primers. With the use of such a primer set, the beta-globin gene region is amplified by denaturation, annealing and DNA synthesis. The amplification cycle is repeated 25-30 times, using the Klenow fragment of DNA polymerase I. The resulting amplified DNA is hybridized with normal and synthetic deoxynucleotide probes using a standard dot-blot method. We have designed a set of primers and experimental conditions which should prove useful to diagnostic centers for detection of numerous beta-thalassemia mutations. 相似文献
48.
Natalia A. Lozinskaya Denis A. Babkov Ekaterina V. Zaryanova Elena N. Bezsonova Alexander M. Efremov Michael D. Tsymlyakov Lada V. Anikina Olga Yu. Zakharyascheva Alexander V. Borisov Valentina N. Perfilova Ivan N. Tyurenkov Marina V. Proskurnina Alexander A. Spasov 《Bioorganic & medicinal chemistry》2019,27(9):1804-1817
Glycogen synthase kinase 3β (GSK-3β) is a widely investigated molecular target for numerous diseases including Alzheimer’s disease, cancer, and diabetes mellitus. Inhibition of GSK-3β activity has become an attractive approach for treatment of diabetes and cancer. We report the discovery of novel GSK-3β inhibitors of 3-arylidene-2-oxindole scaffold with promising activity. The most potent compound 3a inhibits GSK-3β with IC50 4.19?nM. In a cell-based assay 3a shows no significant leucocyte toxicity at 10?µM and is moderately cytotoxic against A549 cells. Compound 3a demonstrated high antidiabetic efficacy in obese streptozotocin-treated rats improving glucose tolerance at a dose of 50?mg/kg body weight thus representing an interesting lead for further optimization. 相似文献
49.
G I Nepomniashchikh V N Efremov V P Tumanov L M Nepomniashchikh 《Biulleten' eksperimental'no? biologii i meditsiny》1986,101(1):105-109
Cells obtained by bronchoalveolar lavage from patients with chronic nonspecific pulmonary inflammatory diseases were studied using light and electron microscopy and radioautography. Five morphological forms of alveolar macrophages, distinct in their structure and 3H-uridine content were described. A higher level of RNA synthesis has been revealed in alveolar macrophage forms 2 and 3 than in forms 1, 4 and 5; with it being lower in polymorphonuclear leukocytes and lymphocytes. It was shown that changes in the number of lavage cells and the structure-to-function characteristics in each cellular population depended on the phase of the inflammatory process. It was postulated that structural and metabolic heterogeneity of alveolar macrophages reflected the successive stages of cellular development from cell-precursors (through activation of protein synthesis) to cells with complete lysosomal cycle and the following phagocytosis. 相似文献
50.
The most adequate method for carrying out radioautographic investigation on proliferation in the chorioallantoic tissues and in the chick embryo proper is dropping 3H-thymidine on the membrane under the shell in the area where the chorioallantois grows under. Using the application method, the radioautographic analysis of proliferation could be performed by the saturation method. 相似文献