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181.
The present work was aimed at analysing the role of inoculated microalgae in nutrient dynamics, bioremediation and biomass production of sewage water. Preliminary microscopic analyses of sewage water revealed the presence of different algal groups, with predominance of Cyanophyta. Among the inoculated strains, Calothrix showed highest dry cell weight (916.67 mg L?1), chlorophyll and carotenoid content in tap water + sewage water (1:1) treatment. Significant removal of NO3-N ranging from 57–78% and PO4-P (44–91%) was recorded in microalgae inoculated tap water + sewage water. The total dissolved solids and electrical conductivity of tap water + sewage water after incubation with Calothrix sp. decreased by 28.5 and 28.0%, accompanied by an increase in dissolved oxygen from 4.4 to 6.4 mg L?1 on the 20th day. Our investigation revealed the robustness of Calothrix sp. in sequestering nutrients (N and P), improving water quality and proliferating in sewage water.  相似文献   
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The present investigation was aimed towards analyzing the potential of consortia of native filamentous microalgal strains (MC2), native unicellular microalgal strains (MC3), and selected microalgae from germplasm (MC1) in terms of nutrient removal, water quality improvement, and biomass production using primary treated sewage water. Highest NO3-N (90 %) and PO4-P (97.8 %) removal was obtained with MC2-inoculated sewage water. Highest decrease in total dissolved solids to 806 from 1,120 mg L?1 and highest increase in dissolved oxygen of 9.0 from 0.4 mg L?1 were obtained using MC2-inoculated sewage water on the sixth day. The biomass production was also highest in MC2 (1.07 g L?1) followed by MC1 and MC3 (0.90 and 0.94 g L?1, respectively) on the sixth day. The consortium of filamentous strains from native environment not only proved promising in nutrient removal efficiency but also led to enhanced biomass. The present study highlighted the utility of such a consortium for sewage wastewater treatment and the promise of sewage water as a growth medium for biomass production.  相似文献   
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Abstract: The in situ freezing technique has been widely used to fix labile metabolites and cellular second messengers in cerebral cortex. In this study, we isolated specific brain regions at 0°C from coronal sections of frozen heads following in situ brain freezing and measured regional concentrations of labile metabolites and cellular messengers. These levels in the cortex were compared with those in cortical punches obtained at freezing temperature (less than −40°C) from the same in situ frozen brains and those of cortex dissected from decapitated animals. In both isoflurane- and pentobarbital-anesthetized animals, we observed that the levels of lactate, free fatty acids, inositol 1,4,5-trisphosphate, and diacylglycerol, as well as the proportion of protein kinase C associated with the membrane fraction, were similar in cortical punches taken at freezing temperature and those dissected at 0°C. However, with animals decapitated at room temperature, cortical and hippocampal levels of lactate, free fatty acids, and inositol 1,4,5-trisphosphate and the proportion of membrane protein kinase C were significantly higher than those of corresponding brain regions isolated at 0°C from in situ frozen brains ( p < 0.05). These results indicate that dissection of cortex and hippocampus at 0°C following in situ freezing will eliminate decapitation-induced production of artifacts and changes in the levels of cellular second messengers such as inositol 1,4,5-trisphosphate, diacylglycerol, and protein kinase C. The present technique, used in conjunction with in situ freezing, will fix cellular second messengers and labile metabolites in several regions of brain and may facilitate accurate characterization of molecular and cellular mechanisms underlying CNS function.  相似文献   
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The present study examined the effect of Cerium on protein synthesis in cultured cardiac myocytes and lung fibroblasts exposed to normal and markedly subnormal levels of Mg2+. Cerium was found to have a general inhibitory effect on protein synthesis in these cell types, including the synthesis of myofibrillar proteins in the cardiac myocytes. Further, the effect of the metal ion was more pronounced in cells exposed to the Mg2+-deficient medium. The possible implications of the observations are discussed.  相似文献   
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We have designed and constructed an inexpensive imaging system based on charge coupled device (CCD) technology and utilized it to demonstrate the sensitivity and rapid detection possible with Lumigen® chemiluminescent reagents. We also report the development of two new chemiluminescent reagents, Lumi-Phos® Plus and Lumigen PS. Lumi-Phos Plus is an ehanced formulation for the rapid detection of alkaline phosphatase on membranes and in solution. It provides excellent images in blotting applications with exposures of under a minute. Lumigen PS represents a new generation of peroxidase detection reagents. The wide dynamic range with excellent linearity, higher signal and lower background than other chemiluminescent reagents make Lumigen PS of unsurpassed value in enzyme-linked immunoassays and nuclic acid probe assays using HRP conjugates.  相似文献   
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Alterations in brain phospholipid metabolism were observed after chronic ethanol administration for 16 days to developing rats. Animals were injected intraperitoneally with 32Pi 16 h prior to killing. Overall uptake of 32Pi by brain did not differ between the control and ethanol-treated groups, which were killed 2 h and 24 h after the last ethanol feeding. Except for an increase in the labeling of myelin after ethanol treatment, the amount of radioactivity recovered in the synaptosomal-mitochondrial and plasma membrane fractions of control and ethanol-treated groups was not different. Relative to the radioactivity of phosphatidylcholines, which indicated no change, there were increases (20-44%) in labeling of ethanolamine plasmalogens, phosphatidic acids, and phosphatidylinositols in cortical synaptosomes from the 2-h ethanol-treated group. In the plasma membrane fractions, however, increases (9-14%) in labeling of phosphatidylserines and phosphatidylinositols were observed in both 2- and 24-h ethanol-treated groups. In both membrane fractions, there was an obvious increase (44-86%) in labeling of polyphosphoinositides at 24 h after withdrawal from ethanol. Results thus indicate an adaptive increase in the biosynthesis of ethanolamine plasmalogen and brain acidic phospholipids due to chronic ethanol administration. Furthermore, the increase in labeling of polyphosphoinositides in the 24-h withdrawal group may reflect the hypoactivity associated with ethanol withdrawal.  相似文献   
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Cell cultures of Ruta graveolens L. were used as a model system to study the relationship between cellular organization and furanocoumarin production. Relative contributions of individual cells were traced using a combination of biochemical and localization techniques in three types of cell cultures: dispersed, aggregated, and organized. The proportion of relative furanocoumarins produced varied with the organization level in cultures. Productive population in dispersed cell culture was 10% which increased to 17% and to 35% in aggregated and organized cell cultures, respectively. Large cell clusters accumulating furanocoumarins were restricted to organized cell cultures. In these lines, sites for psoralen, bergapten, and xanthotoxin accumulation were spatially separated from each other, which has been reported for the first time. Variation in production was due to change in relative size of productive population in the three types of cultures studied. A model has been proposed for differential furanocoumarin producing ability of cells based on differentiation levels.  相似文献   
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