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1.
E A Serbinova R A Bakalova Ts S Sto?chev V E Kagan 《Biulleten' eksperimental'no? biologii i meditsiny》1986,102(10):419-421
The efficacy of lipid peroxidation inhibition by the natural antioxidant alpha-tocopherol and 2,2,5,7,8-pentamethyl-6-hydroxy-chromane (PMC), a derivative without hydrocarbon tail, as well as by the synthetic antioxidant 4-methyl-2,6-diterbutyl phenol (BHT) and its phospholipid derivative was studied in the membranes of rat liver microsomes and mitochondria. The presence of hydrocarbon tail in the antioxidant molecule determines the decrease of antioxidant efficiency in biomembranes. PMC and BHT exert a destructive effect on biomembranes, leading to an increase in their permeability to ions. This evidence suggests that the presence of hydrocarbon tail in the molecules of natural antioxidants provides not only for a relatively high antioxidant efficiency but also for a structural stability of biomembranes. 相似文献
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G M Ka?nova D Markovska D Staneva V E Kagan 《Biulleten' eksperimental'no? biologii i meditsiny》1990,109(1):35-37
Looking for an appropriate model of accelerated aging in vivo we investigated the content of endogenous products of lipid peroxidation (LP) in the rat brain after single or 4 day-lasting intramuscular injection of complex-bind iron (ferum Hausman, 50 mg/kg body weight) like promoter of LP. We found that the single administration of this iron complex fails to induce endogenous LP; after 4 day-application of iron we observed significant increase in content of primary (lipid peroxides) and final (fluorescent) products of LP. Iron-promoted activation of endogenous LP could be abolished by animal pretreatment with the natural antioxidant alpha-tocopherol. The calcium antagonist nifedipine didn't affect the content of endogenous LP products neither alone nor in combination with alpha-tocopherol. 相似文献
3.
EA Dukhanina TI Lukyanova EA Romanova V Guerriero NV Gnuchev GP Georgiev DV Yashin LP Sashchenko 《Cell cycle (Georgetown, Tex.)》2015,14(22):3635-3643
PGRP-S (Tag7) is an innate immunity protein involved in the antimicrobial defense systems, both in insects and in mammals. We have previously shown that Tag7 specifically interacts with several proteins, including Hsp70 and the calcium binding protein S100A4 (Mts1), providing a number of novel cellular functions. Here we show that Tag7–Mts1 complex causes chemotactic migration of lymphocytes, with NK cells being a preferred target. Cells of either innate immunity (neutrophils and monocytes) or acquired immunity (CD4+ and CD8+ lymphocytes) can produce this complex, which confirms the close connection between components of the 2 branches of immune response. 相似文献
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Kulikov AV Bogatyrenko VR Likhtenshteĭn GI Allakhverdiev SI Klimov VV Shuvalov VA Krasnovskiĭ AA 《Biofizika》1983,28(3):357-362
The influence of Mn on saturation curves of ESR spectra of Ph(-) and P(+)(680) at 1-200K in samples with different content of Mn has been studied. An analysis of these data and those on photoinduced changes of fluorescence yield of chlorophyll leads to the conclusion that the Mn-containing centre in Photosystem 2 is a cluster of 4 Mn atoms, two of which can be replaced by Mg(2+) or any other divalent metal. The distances between Mn Na Ph as well as between Mn and P(680) have been estimated. 相似文献
6.
Morphology of pollen grains collected from healthy and virus infected plants ofChenopodium quinoa L.,Chenopodium album L. andNicotiana tabacum L. cv. Samsun was investigated using scanning electron microscopy (SEM). Pollen grains from tobacco plans infected with tobacco mosaic virus (TMV) were smaller, with rounded shape and conspicuous deformation of aperture unlike oval and smooth pollen grains from healthy plants. No morphological alterations were observed inC. quinoa andC. album plants infected with TMV and cucumber mosaic virus (CMV). Polyacrylamide gel electrophoresis of pollen proteins revealed substantial quantitative and qualitative differences in protein components of pollen grains collected from healthy and virus infected plants 相似文献
7.
The effect of tetracycline and tetraolean on the shifts in the plasma-cell elements was studied experimentally on male albino rats of Wister line and rabbits immunized with foreign erythrocytes and typhoid fever vaccine respectively. It was noted that prolonged use of the antibiotics for 10 to 12 days inhibited proliferation of the plasmic cells, the inhibitory effect of tetracycline being more pronounced. At the same time an inhibitory effect of the antibiotics on the antibody formation in the animals was found in the experiments. 相似文献
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A large-scale study of short retroposon (SINE) B1 has been conducted in the genome of rodents from most of the known families of this mammalian order. The B1 nucleotide sequences of rodents from different families exhibited a number of characteristic features including substitutions, deletions, and tandem duplications. Comparing the distribution of these features among the rodent families, the currently discussed phylogenetic relationships were tested. The results of analysis indicated (1) an early divergence of Sciuridae and related families (Aplodontidae and Gliridae) from the other rodents; (2) a possible subsequent divergence of beavers (Castoridae); (3) a monophyletic origin of the group Hystricognathi, which includes several families, such as porcupines (Hystricidae) and guinea pigs (Caviidae); (4) a possible monophyletic origin of the group formed by the remaining families, including six families of mouselike rodents (Myodonta). Various approaches to the use of short retroposons for phylogenetic studies are discussed. 相似文献