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1.
Louise E. Anderson 《Biochemical and biophysical research communications》1981,99(4):1199-1202
Transaldolase is inactivated when intact pea leaf chloroplasts are irradiated. This light inactivation is 3-(3,4-dichlorophenyl)-1,1-dimethyl urea, arsenite and sulfite-sensitive, implicating the Light Effect Mediator system in light inactivation of this oxidative pentose phosphate pathway enzyme. 相似文献
2.
A new method for the analysis of NMR data in terms of the solution structure of proteins has been developed. The method consists of two steps: first a systematic search of the conformational space to define the region allowed by the initial set of experimental constraints, and second, the narrowing of this region by the introduction of additional constraints and optional refinement procedures. The search of the conformational space is guided by heuristics to make it computationally feasible. The method is therefore called the heuristic refinement method and is coded in an expert system called PROTEAN. The paper describes the validation of the first step of the method using an artificial NMR data set generated from the known crystal structure of sperm whale carbon monoxymyoglobin. It is shown that the initial search procedure yields a low-resolution structure of the myoglobin molecule, accurately reproducing its main topological features, and that the precision of the structure depends on the quality of the initial data set. 相似文献
3.
Summary Under controlled conditions in pots filled with sand, vermiculite and field soil, inoculation withA. brasilense-Cd ATCC 29729 or withAzotobacter chroococcum caused increases above controls in the weight and N content of panicles ofSetaria italica. In no case, however, did N increases in test plants exceed the initial total N content. High acetylene reduction activities (1,000–2,000 nmole/h/pot) could be found only in plants inoculated withAzospirillum. Inoculation withAzospirillum (strain-Cd) in the field caused a significant increase above noninoculated controls of 18.5% in shoot dry weight, ofSetaria italica. Azotobacter caused a non significant increase of 8%. No significant differences were found between yields ofSetaria italica grown in soil inoculated withA. chroococcum, and those of plants grown in the presence ofA. vinelandii. A. brasilense-Cd was more effective in the field thanA. brasilense Sp-7 ATCC 29145. The results suggest that Azospirillum may increase yields ofS. italica more efficiently than Azotobacter under local field conditions. 相似文献
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Zdzislaw Przybylski 《Archives Of Phytopathology And Plant Protection》2013,46(1):47-51
The paper presents the yield-forming effect of Sandovit on field bean. The field experiments, carried out in the experimental field of the Regional Experimental Centre in Boguchwala near Rzeszów, showed the significant effect this product has on accelerating the growth of plants and their yield. A significant difference was proved between the experimental object and the control one regarding the number of pods set on a plant and filling them with seeds. The result was an increase in the seed crop by 22.3% in relation to the control object. The effect of Sandovit on decreasing the degree of damage to the field bean seeds was also proved. 相似文献
7.
Marco La Rosa Carl H. Schiesser Alfred Uhlherr Calum J. Drummond Keith Moody Robert Bohun 《Molecular simulation》2013,39(8-9):791-806
A coarse-grained model for simulation of interfacial phenomena in aqueous systems has been developed. The model captures the hydrophobic effect by only considering the structure and cohesiveness of water. Monte Carlo (MC) simulations of water-oil mixtures show that low concentrations of oil are solvated with little perturbation of the hydrogen bonding network structure of the water, while high concentrations of oil are excluded altogether. Analysis of the water structure in the simulations indicates that the water molecules maintain close to four coordination in the presence of solutes and the distribution of bond angles is not markedly affected by the presence of solutes. MC simulations of an alkane oligomer in water and a poly(ethylene oxide) (PEO) oligomer in water indicate that the chains are quite flexible and also do not perturb the network structure of the water phase. 相似文献
8.
《Electromagnetic biology and medicine》2013,32(2):112-121
It has been reported that human subjects exposed to electromagnetic fields exhibit changes in human EEG signals at the frequency of stimulation. The aim of the present study was to expose different parts of the brain to extremely low-frequency magnetic fields locally and investigate EEG power spectrum alters at the frequency of stimulation. EEG relative power spectrum were evaluated at 3, 5, 10, 17, and 45 Hz frequencies at T4, T3, F3, Cz, and F4 points, respectively, when these points were exposed to magnetic fields with similar frequencies and 100 μT intensity. The paired t-test results showed that power value of EEG did not alter significantly at the frequency of stimulation (P < 0.05). Further, significant changes in different EEG bands caused by locally exposing to ELF-MF in different points of brain were observed. The changes in the EEG bands were not limited necessarily to the exposure point. 相似文献
9.
Ayşe Eken Onur Erdem Zorica Arsova‐Sarafinovska Cemal Akay Ahmet Sayal Nadica Matevska Ljubica Suturkova Koray Erten Yaşar Özgök Aleksandar Dimovski Ahmet Aydin 《Journal of biochemical and molecular toxicology》2013,27(3):213-218
Manganese superoxide dismutase (MnSOD) is the most effective antioxidant enzyme in mitochondria and protects cells from reactive oxygen species‐induced oxidative damage. The aim of this study was to investigate the association between MnSOD Ala‐9Val gene polymorphism and prostate cancer (PCa) risk in Turkish men with prostate cancer. 33 patients with PCa and 81 control individuals were included in the study. We observed an association between MnSOD Ala/Ala frequency and a higher PCa risk. In addition, we found that the increased risk of early‐onset PCa (under age of 65) in the men homozygous for Ala allele was higher than the men homozygous for Val allele. However, we determined that MnSOD Ala‐9Val genotype was not associated with the aggressiveness of the disease. The results of our study suggest that MnSOD Ala/Ala genotype may influence on early‐onset of PCa patients, but no effect on subsequent development of the disease in Turkish men. However, our study has a limitation that is small numbers of individuals for cases and controls. Therefore, the presented study limited our statistical power to fully investigate the gene polymorphism on cancer risk. © 2013 Wiley Periodicals, Inc. J BiochemMol Toxicol 27:213‐218, 2013; View this article online at wileyonlinelibrary.com . DOI 10.1002/jbt.21472 相似文献
10.
In the absence of redox-active transition metal ions, the removal of Tempol by Trolox occurs by a simple bimolecular reaction that, most probably, involves a hydrogen transfer from phenol to nitroxide. The specific rate constant of the process is small (0.1 M m 1 s m 1 ). Metals can catalyze the process, as evidenced by the decrease in rate observed in the presence of diethylenetriaminepentaacetic acid (DTPA). Furthermore, addition of Fe(II) (20 w M ferrous sulfate and 40 w M EDTA) produces a noticeable increase in the rate of Tempol consumption. 相似文献