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Journal of Plant Growth Regulation - Fullerenols are carbon nanoparticles that have been declared as free radical sponges. There is a need to take a prudent path toward its applications in various...  相似文献   
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Annual gross primary productivity in mesotrophic Shahidullah Hall pond (Dhaka, Bangladesh) was 1383.35 g C m−2 y−1 (arithmetic mean). Daily primary productivity (between 1.6 and 6.8 g C m−2 d−1 was correlated with chlorophylla, day length and dissolved silica. Chlorophylla related significantly withk, incident light, SRP, alkalinity and conductivity. A negative correlation existed between biomass and rainfall. Productivity, biomass, conductivity, alkalinity, and SRP increased after mid-winter.k, I k andZ eu varied according seasonally.P max related directly with temperature. Seasonal variation of ∝ B was 0.0049–0.0258 mg C (mg chla mmol PAR)−1 m−2. Q10 was 2.12, community respiration 1334.99 g C m−2 y−1, and the underwater light climate 186.43μE m−2 s−1.  相似文献   
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Molecular and Cellular Biochemistry - The excitatory amino acids (EAA), L-glutamate and L-aspartate were initially advanced as excitatory neurotransmitters some 30 years ago but in the past few...  相似文献   
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The contents of mitochondrial inner membrane protein complexes were compared in normal liver and in Zajdela hepatoma mitochondria by the immunotransfer technique. Antibodies against core proteins 1 and 2, cytochrome c1, the iron-sulfur protein of Complex III, subunits I and II of cytochrome oxidase, and the alpha and beta subunits of the F1-ATPase were used. In addition, antibodies against a primary dehydrogenase, beta-hydroxybutyrate dehydrogenase, as well as the outer membrane pore protein were used. The results indicate that the components of the cytochrome chain and porin are greatly enriched in hepatoma mitochondria compared to normal rat liver mitochondria. This enrichment was also reflected in the rates of respiration in tumor mitochondria using a variety of substrates. Enrichment of porin may partially account for increased hexokinase binding to tumor mitochondria. In contrast to the respiratory chain components, the F1-ATPase and F0 (measured by DCCD binding) were not increased in tumor mitochondria. Thus, Zajdela hepatoma mitochondria components are nonstoichiometric, being enriched in oxidative capacity but relatively deficient in ATP synthesizing capacity. Finally, beta-hydroxybutyrate dehydrogenase, which is often decreased in hepatoma mitochondria, was shown here by immunological methods to be decreased by only 40%, whereas enzyme activity was less than 5% of that in normal rat liver.  相似文献   
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The distribution of hexokinase between bound and soluble forms was studied by digitonin fractionation of Zajdela hepatoma ascites cells maintained under various metabolic conditions. Addition of glucose to Zajdela cells respiring on endogenous substrates induces an immediate inhibition of respiration by 50-60% ( Crabtree effect), and a production of acid due to glycolysis. Acid production decreases abruptly after 60s to 50% of the initial rate. The ATP/ADP ratio is not altered by the addition of glucose or by different rates of glycolysis. The uncoupling agent carbonyl cyanide m-chlorophenylhydrazone decreases the ATP/ADP ratio by 10-fold in cells respiring on endogenous substrate, but has little effect on cells oxidizing glucose. Rapid fractionation of the cells under these various metabolic conditions revealed no change in the distribution of hexokinase. Approx. 75% of hexokinase is bound in all cases, in contrast with lactate dehydrogenase, 95% of which was in the soluble form. Longer-term incubations (to 20 min) revealed only slight (10-15%) increases in soluble hexokinase in cells incubated with glucose. Various metabolic inhibitors had little additional affect on the subcellular distribution of hexokinase. Thus a rapid release of hexokinase from mitochondrial membrane is not a mechanism by which glycolysis is regulated in rapidly growing Zajdela hepatoma.  相似文献   
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A man who had worked for 16 years in the manufacture of a potent corticosteroid was found to be suffering from chronic adrenocortical insufficiency attributed to chronic absorption of the glucocorticoid. Eleven other symptom-free workers were therefore screened. Two of these workers, like the first patient, gave grossly abnormal responses to the Synacthen (tetracosactrin) test; one had been employed for only seven months. All 12 men had facial plethora, suggesting absorption of the drug in spite of their having adhered to the safety precautions. All workers manufacturing potent steroids should therfore be screened regularly by measurement of their plasma cortisol concentrations and should be moved regularly to processing other drugs.  相似文献   
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Mycelium of Fusarium oxysporum grown on a glucose-containing medium lacked fructosyl transferase and invertase activities. Synthesis of fructosyl t  相似文献   
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