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101.
Using PCR analysis and immunofluorescence staining, we have investigated the expression of homeobox genes Vsx1/Chx10-1 and Vsx2/Chx10 from the Vsx family (visual system homeobox) during retinal morphogenesis in the chicken Gallus domesticus. It was found that the expression of the studied genes starts at the early stages of embryogenesis. It was shown that the proteins of Vsx1 and Vsx2 are localized in the bipolar cells of the inner nuclear layer of the forming retina. The participation of Vsx1/Chx10-1 and Vsx2/Chx1 in the regulation of retinal cell differentiation in various species of vertebrates and in humans was discussed.  相似文献   
102.
Experimental data on the effect of the natural immunopeptide tuftsin and its synthetic counterpart on hemostasis parameters in vitro and in vivo when administered intranasally to animals (white laboratory rats) are given. It has been shown that in vitro both preparations induced a fibrin-depolymerization effect on fibrin that is not stabilized by factor XIIIa. For each preparation, it was noted that, when administered to rats, simultaneous antiplatelet, anticoagulant, and fibrin-depolymerization effects were observed in the blood plasma, with Selank having a more pronounced effect.  相似文献   
103.
On day 7 of chronic cold stress, concentration of corticosterone in plasma was established to increase, zymosan-induced production of reactive oxygen species was activated, and IL-10 synthesis by macrophages was enhanced regardless of the opiate receptor blockade. Increase in the concentration of corticosterone was independent of the blockade of opioid receptors, whereas the zymosan-induced increase in the production of oxygen radicals and activation of the spontaneous production of IL-10 was blocked in mice by naloxone. Chronic cold stress had no effect on the production of IL-1β and TNF-α.  相似文献   
104.
Pure cultures of indigenous microorganisms Acidithiobacillus ferrooxidans strain TFUd, Leptospirillum ferrooxidans strain LUd, and Sulfobacillus thermotolerans strain SUd have been isolated from the oxidation zone of sulfide copper ore of the Udokanskoe deposit. Regimes of bacterial-chemical leaching of ore have been studied over a temperature range from −10 to +20°C. Effects of pH, temperature, and the presence of microorganisms on the extraction of copper have been shown. Bacterial leaching has been detected only at positive values of temperature, and has been much more active at +20 than at +4°C. The process of leaching was more active when the ore contained more hydrophilic and oxidized minerals. The possibility of copper ore leaching of the Udokanskoe deposit using sulfuric acid with pH 0.4 at negative values of temperature and applying acidophilic chemolithotrophic microorganisms at positive values of temperature and low pH values was shown.  相似文献   
105.
Understanding the interactions among microbial communities, plant communities and soil properties following deforestation could provide insights into the long-term effects of land-use change on ecosystem functions, and may help identify approaches that promote the recovery of degraded sites. We combined high-throughput sequencing of fungal rDNA and molecular barcoding of plant roots to estimate fungal and plant community composition in soil sampled across a chronosequence of deforestation. We found significant effects of land-use change on fungal community composition, which was more closely correlated to plant community composition than to changes in soil properties or geographic distance, providing evidence for strong links between above- and below-ground communities in tropical forests.  相似文献   
106.
Invertebrates from the Sea of Okhotsk were studied as a source of proteins that are capable of binding to lipopolysaccharides (LPSs) of gram-negative bacteria. A DOT analysis using dansyl-labeled LPS that we developed revealed LPS-binding proteins in blood-cell lysates of 21 out of 33 investigated species of invertebrates. Most of the investigated species with positive LPS-binding activity were decapod crustaceans (class Malacostraca, phylum Arthropoda). Hemocyte lysates from the red king crab Paralithodes camtschaticus and the sculptured shrimp Sclerocrangon boreas contained several LPS-binding proteins with different molecular weights. LPS-binding proteins were found for the first time in echinoderms (classes Holothuroidea, Asteroidea, and Echinoidea), sipunculans, and brachiopods.  相似文献   
107.
α1-Acid glycoprotein (orosomucoid) was purified from the human and murine blood sera using phenol deproteinization. As opposed to the murine protein, the human orosomucoid bound the fluorescent dye ethidium bromide but lost this ability after treatment with β-mercaptoethanol, which breaks disulfide bonds. Disulfide bonds between the Cys23 and Cys165 residues of the human orosomucoid and between the Cys91 and Cys184 residues of the murine orosomucoid were identified.  相似文献   
108.
A possible physiological mechanism of legume-Rhizobium symbiosis, consisting in regulation of the intensity of oxidative processes by the macrosymbiont in response to infection with Rhizobium, was analyzed using our own and published data. The results used in the analysis included data on the content of reactive oxygen species (O 2 ·? and H2O2), activity of antioxidant enzymes (superoxide dismutase, catalase, and peroxidase), and intensity of lipid peroxidation proceeding with the involvement of lipophilic phenolic compounds of the microsymbiont.  相似文献   
109.
110.
Activation of neutrophils in the presence of gold nanoparticles is accompanied by formation of free-radical peroxidation products, recorded as a flash of chemiluminescence. The basis for the activation mechanism has its origins most likely in the influence of the gold particles on the membrane surface potential of neutrophils. Assessment of changes in the fluorescence intensity of the negatively charged ANS probe on the surface of model membranes upon adding different concentrations of gold nanoparticles indicates a change in the membrane surface charge density, which can cause cell activation.  相似文献   
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