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1.
In July 2010, abnormally high water temperature (25–29°C), as well as increased biomass and phytoplankton production caused intensive development of heterotrophic bacteria and heterotrophic nanoflagellates. It was found that the abundance, biomass, and production of heterotrophic bacterioplankton, as well as the abundance and biomass of heterotrophic nanoflagellates, and the number of planktonic viruses, which were calculated on average for the reservoir under study, turned out to be higher in the years with lower water temperature (20–23°C). The virus-induced mortality of bacterioplankton in the Oka River and the Cheboksary Reservoir averaged 25.4 ± 3.4 and 22.4 ± 2.7% of the daily bacterioplankton production.  相似文献   
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Bacterial bioluminescence was applied to detection of general toxicity (MIT test) and genotoxicity (SOS-lux test) of some chemicals, seawater, and fresh water. The SOS-induced luminescence of E. coli WP2s (cda::luxCDABE) cells was higher than in E. coli C 600 (cda::luxCDABE) at 37 degrees C and pH 6.5. The mutagenic effect of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), mitomycin C, and hydrogen peroxide determined from the induction of E. coli WP2s cell luminescence was detected at lower concentrations than in the assessment of reversion frequencies. General toxicity was demonstrated by using luminescence inhibition for hydrogen peroxide, Zn2+, and Cd2+ at low concentrations. Regions of the Krasnodar Krai where sea and fresh waters exerted toxic action on luminescence were determined by the microbioluminescent method.  相似文献   
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Kang  Yun Hee  Ji  Na Young  Lee  Chung Il  Lee  Hee Gu  Kim  Jae Wha  Yeom  Young IL  Kim  Dae Ghon  Yoon  Seung Kew  Kim  Jong Wan  Park  Pil Je  Song  Eun Young 《Amino acids》2011,40(3):1003-1013
Amino Acids - Endothelial cell-specific molecule-1 (ESM-1) is a secretory proteoglycan comprising a mature polypeptide of 165 amino acids and a single dermatan sulfate. The aim of this study was to...  相似文献   
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Human perception of dissonant and consonant chords was studied by analyzing brain evoked activity. It was found that the perception of dissonant chords was accompanied by activation of the right frontal lobe, which controls negative emotions. Consonant chords activated the left frontal region, which controls positive emotions.  相似文献   
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We investigated effects of sodium nitroprusside (SNP), the donor of nitric oxide (NO), on the growth and hormonal system of wheat plants (Triticum aestivum L.) in normal conditions and after salt stress (2% NaCl). During germination of seeds treated with SNP (50–500 μM), we obtained the SNP concentration (200 μM) optimal for stimulation of seedling growth estimated by increase in seed germination capacity and seedlings' linear sizes and their fresh and dry biomass. A comparative analysis of SNP (200 μM) effects, after seed germination in the medium with SNP or pretreatment of 3-day-old seedlings, showed SNP ability to increase the wheat plant resistance to subsequent effects of sodium chloride salinity at both treatment methods. Protective SNP effects appeared in the reduction of stress inhibitory action on seedling growth rates and significant reduction in the level of lipid peroxidation and exosmosis of electrolytes. An important contribution to realization of the growth-stimulating and protective effects of NO is associated with its ability to influence the state of the hormonal system of wheat plants due to an increase in the concentration of hormones of a cytokinin nature under normal conditions and the prevention of a decrease in their level under stress.  相似文献   
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The potentialities of diffuse optical spectroscopy for the noninvasive estimation of the oxygen state of experimental tumors have been demonstrated. The distribution of total, oxygenated and deoxygenated hemoglobin, as well as the level oxygen saturation of blood have been shown using two tumor models differing in the histological structure and functional characteristics. The results obtained by the optical method have been verified by immunohistochemical examination of tissue specimens with the exogenous hypoxia marker pimonidazole.  相似文献   
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Transient receptor potential canonical channel (TRPC) is a nonselective cation channel permeable to Ca2+, which express in many cell types, including neurons. However the alterations in TRPC receptor expressions in response to status epilepticus (SE) have not been explored. Therefore, the present study was designated to elucidate the roles of TRPC3 in neuronal death and vasogenic edema within the rat piriform cortex (PC) following SE. In non-SE animals, TRPC3 immunoreactivity was abundantly detected in the PC. Following SE, TRPC3 immunoreactivity was increased in neurons. Furthermore, TRPC3 expression was detected in endothelial cells that did not contain it in non-SE animals. Loss of SMI-71 (a blood–brain barrier antigen) immunoreactivity was also observed in TRPC3 positive endothelial cells. In addition, FJB positive neurons and vasogenic edema were noticeably detected in the PC. To directly determine whether TRPC3 activation is correlated to SE-induced vasogenic edema formation and neuronal damages in the PC, the effect of Pyr-3 (a TRPC3 antagonist) on SE-induced insults were investigated. Pyr-3 infusion effectively attenuated vasogenic edema in the PC as compared to the vehicle. Therefore, our findings indicate that TRPC3 activation/overexpression induced by SE may involve BBB disruption and neuronal damages in the rat PC following SE. Therefore, the present study was TRPC3 may play an important role in SE-induced vasogenic edema formation through BBB disruptions in the rat PC.  相似文献   
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Members of the Deinococcaceae (e.g., Thermus, Meiothermus, Deinococcus) contain A/V-ATPases typically found in Archaea or Eukaryotes which were probably acquired by horizontal gene transfer. Two methods were used to quantify the extent to which archaeal or eukaryotic genes have been acquired by this lineage. Screening of a Meiothermus ruber library with probes made against Thermoplasma acidophilum DNA yielded a number of clones which hybridized more strongly than background. One of these contained the prolyl tRNA synthetase (RS) gene. Phylogenetic analysis shows the M. ruber and D. radiodurans prolyl RS to be more closely related to archaeal and eukaryal forms of this gene than to the typical bacterial type. Using a bioinformatics approach, putative open reading frames (ORFs) from the prerelease version of the D. radiodurans genome were screened for genes more closely related to archaeal or eukaryotic genes. Putative ORFs were searched against representative genomes from each of the three domains using automated BLAST. ORFs showing the highest matches against archaeal and eukaryotic genes were collected and ranked. Among the top-ranked hits were the A/V-ATPase catalytic and noncatalytic subunits and the prolyl RS genes. Using phylogenetic methods, ORFs were analyzed and trees assessed for evidence of horizontal gene transfer. Of the 45 genes examined, 20 showed topologies in which D. radiodurans homologues clearly group with eukaryotic or archaeal homologues, and 17 additional trees were found to show probable evidence of horizontal gene transfer. Compared to the total number of ORFs in the genome, those that can be identified as having been acquired from Archaea or Eukaryotes are relatively few (approximately 1%), suggesting that interdomain transfer is rare.  相似文献   
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