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1.
O G Ianovski? L A Zakharova A M Vasilenko 《Biulleten' eksperimental'no? biologii i meditsiny》1990,109(1):55-57
In addition to the immunostimulating activity, bone marrow mediators, myelopeptides (MP) show the dose-dependent effect on the development of pain sensitivity in mice. When injected in nanogram amounts, MP induce hyperalgesia and 3-9 fold higher production of antibodies against SREC. When injected in milligram amounts, they exhibit hypoalgesic effect and no influence on antibody production. Immunostimulating effect in MP (mol, mass less than 1 KD, fraction 3) is accompanied with hypoalgesia. Bone marrow factors of mol. masses 40-150 KD (fraction 1) eluted at Sephadex G-25 gel-filtration before MP enhance the pain sensitivity tHreshold and show a potent immunodepressive effect. Thus the bone marrow factors are capable of exhibiting the opposite effects on the immune system in the pain control system that evidences the tight interrelation between these systems. 相似文献
2.
S. M. Molchanova A. N. Moskvin I. Yu. Zakharova L. A. Yurlova I. Yu. Nosova N. F. Avrova 《Journal of Evolutionary Biochemistry and Physiology》2005,41(1):39-46
The effect of a two-vessel forebrain ischemia (induced by occlusion of carotid arteries and hypotension), subsequent reperfusion, and administration of indomethacin and quinacrine on the Na+,K+-ATPase activity and diene conjugate content was studied in various rat forebrain fields. The most pronounced metabolic alterations were observed during ischemia and reperfusion. Under these effects, there was a statistically significant reduction of the Na+,K+-ATPase activity in the brain cortex and striatum and an increase of the diene conjugate content in the rat brain cortex in comparison with sham-operated animals. Injection of indomethacin, a cyclooxygenase inhibitor, to rats subjected to ischemia and reperfusion, resulted to a statistically significant increase of the Na+,K+-ATPase activity in the brain cortex, hippocampus, and striatum (p < 0.02) as compared with control animals. The diene conjugate content in the rat brain cortex during brain ischemia and reperfusion was statistically significantly lower in the rats injected with indomethacin. The effect of quinacrine (a blocker of phospholipase A2) was similar to that of indomethacin in the rat cortex, whereas in the rat striatum and hippocampus, the quinacrine effect during ischemia and reperfusion was less marked than that of indomethacin. The obtained data indicate the ability of inhibitors of the arachidonic pathway of free radical formation to normalize the Na+, K+-ATPase activity during brain ischemia. There also revealed local peculiarities of metabolic disturbances in different regions of the rat forebrain during ischemia and reperfusion.Translated from Zhurnal Evolyutsionnoi Biokhimii i Fiziologii, Vol. 41, No. 1, 2005, pp. 33–38.Original Russian Text Copyright © 2005 by Molchanova, Moskvin, Zakharova, Yurlova, Nosova, Avrova. 相似文献
3.
The paper analyzes humus profiles of mountain-chestnut soils of a complex catena situated within the Khemchik dry-steppe area
of the Central Tuva Depression. The study has shown that humus profile characteristics are determined by both slope aspects
and position in the catena. Humus profiles imprint all environmental changes of soil formation and functioning even if these
changes are not expressed in soil morphology. The materials obtained during the study may serve as basis for long-term monitoring
of slope soil behavior and for revealing local soil variability in changing environment. 相似文献
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Iu V Rodionov T V Avilova E V Zakharova L S Platonenkova A M Egorov I V Berezin 《Biokhimii?a (Moscow, Russia)》1977,42(10):1896-1904
NAD-Dependent formate dehydrogenase (FDH) has been isolated from methylotrophyc strain Bacterium sp 1 by (NH4)2SO4 fractionation of cell extract, ion-exchange chromatography and preparative isotachophoresis. Preparation of FDH is homogeneous in analytical polyacrylamide gel electrophoresis and under ultracentrifugation. Sedimentation coefficient of FDH is 4.9S. Mikhaelis constants are 1.1-10(-4) M for NAD and 1.5-10(-2) M for formate. In the absence of sulfhydril compounds FDH is unstable, but it is stable in the presence of mercaptoethanol or ditiotreitol. 相似文献
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Iu A Knirel' N V Tanamar M A Soldatkina I Ia Zakharova 《Bioorganicheskaia khimiia》1988,14(12):1684-1689
On mild acid degradation of the Pseudomonas cepacia strain IMV 4176 lipopolysaccharide, two polysaccharides were obtained, one of which is a homopolymer of N-acetyl-D-galactosamine and the other is composed of equal amounts of N-acetyl-D-galactosamine and D-ribose. Partial hydrolysis with aqueous oxalic acid caused depolymerization of the heteropolysaccharide, and the homopolysaccharide was isolated in the individual state. On the basis of methylation and 13C NMR analysis, it was concluded that both polysaccharides are built up of disaccharide repeating units having the following structures: ----4)-alpha-D-GalpNAc-(1----4)-beta-D-GalpNAc-(1---- and ----4)-alpha-D-GalpNAc-(1----2)-beta-D-Ribf-(1----. The heteropolysaccharide from P. cepacia strain 4176 is identical by the structure of the repeating unit to the O-specific polysaccharide of P. cepacia strain IMV 4202 (serotype 3), Pseudomonas aeruginosa O12 and Serratia marcescens O14. 相似文献
10.
Isolation and characterization of a large,neurite-associated glycoconjugate from neuroblastoma cells 下载免费PDF全文
A high molecular weight glycoconjugate has been isolated from neurite-producing neuronal tumor cells in culture and has been designated as I(0) based on its elution characteristics in gel filtration chromatography. This molecule cannot be found in a variety of nonneuronal cells. I(0) is found in the substratum-attached material or cell fraction of neurite-producing neuroblastoma cells, depending upon culture conditions. It is found in the substratum-bound fraction of B104 rat neuroblastoma cells during serum starvation and in the EGTA-detached cell fraction of B104 cells grown in chemically defined N2 medium. It occurs only in the cell fraction of the human neuroblastoma line Platt. Examination of behavioral variants of the B104 rat line further strengthens the association of I(0) with neurite production; the constitutive neurite-producing E(R)B9 variant contains I(0) while the non-neurite-producing E(R)A11 variant does not. I(0) is large, eluting in the void volume of sepharose-CL2B columns. Radioiodination of intact cells with lactoperoxidase shows I(0) to be a cell surface component. Metabolic radiolabeling studies show that it contains a high proportion of polysaccharide to protein, does not contain mannose, and is unsulfated. Alkaline borohydride reduction release two size classes of large polysaccharide chain. The alkaline reduction results, along with the mannose incorporation studies, show the presence of O-glycosidic linkages and few, if any, N-linkages. Resistance to nitrous acid deamination, insensitivity to glycosaminoglycan lyases, and the absence of sulfation, indicate that I(0) does not contain the glycosaminoglycans hyaluronic acid, chondroitin-, dermatan-, or heparin- sulfates. Affinity column chromatography reveals high binding affinity of I(0) to polyornithine and no binding to gelatin (collagen) or the glycosaminoglycans hyaluronate and heparin. These studies describe a unique high molecular weight glycoconjugate on the surface of neurite-producing neuroblastoma cell lines from two species. 相似文献