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781.
Extracts from the stems and leaves of Pitavia punctata Mol. were examined. The neutral fraction yielded β-sitosterol, daucosterin, quercetin, avicularin, and the previously undescribed quercetin 3-rhamnosylarabinoside. Braylin was co-extracted with the basic constituents, dictamnine, skimmianine and γ-fagarine. Acid hydrolysis of the leaves yielded cyanidin and delphinidin. 相似文献
782.
Effects on Plant Growth Produced by Azotobacter paspali Related to Synthesis of Plant Growth Regulating Substances 总被引:2,自引:2,他引:0
S ummary . Treating seedling roots of several plant species with cultures of Azotobacter paspali changed plant growth and development and significantly increased weight of leaves and roots; effects were probably caused by plant growth regulators. Culture supernatant fluids contained indolyl-3-acetic acid, at least 3 gibberellins and 2 cytokinins. The added inoculum of A. paspali survived in plant rhizospheres for only a few weeks and no nitrogen was fixed in the root zone of young Paspalum notatum , the grass with which A. paspali is associated. 相似文献
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S. T. Zakhidov T. L. Marshak E. A. Malolina A. Yu. Kulibin I.A. Zelenina S. M. Pavluchenkova V. M. Rudoi O. V. Dement’eva S. G. Skuridin Yu. M. Evdokimov 《Biochemistry (Moscow) Supplemental Series A: Membrane and Cell Biology》2010,4(3):293-296
The effect of gold nanoparticles on mouse epididymal sperm has been studied using the model system of nuclear chromatin decondensation
in vitro. It is shown that the treatment of gametes, preliminary membrane-freed by sodium dodecyl sulfate, in the mediums
containing gold nanoparticles (with diameter ∼2.5 nm) in concentrations 1.0 × 1015 or 0.5 × 1015 particles/ml and following incubation in dithiothreitol solution (DTT) resulted in failure of chromatin decondensation process
and nucleus structure. We conclude that gold nanoparticles possess spermatotoxicity. The mechanism of cytotoxic effect of
gold nanoparticles may be related with their interaction with molecules of double-helix DNA. The model system studied in this
research is applicable for further investigations of cytotoxic effects of nanoparticles of different origin and made of different
metals. 相似文献
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The dynamical structure of the RNA in alfalfa mosaic virus studied by 31P-nuclear magnetic resonance
The structure of the viral RNA in alfalfa mosaic virus (AlMV) was investigated by means of 31P-nuclear magnetic resonance (NMR). It was found that the 31P-NMR line width of AlMV Top a particles is significantly smaller than that of the larger Bottom particles. At low temperatures, the totational correlation time of the 31P nuclei essentially equals the tumbling rate of the virus particle, indicating that the RNA is contained rigidly inside the virion. At more elevated temperatures, the NMR line width sharpens more than expected on the basis of viscosity changes and the RNA exhibits internal mobility. The occurrence of internal mobility is paralleled by an increased internal mobility of the N-terminal part of the coat protein, as could be observed by 1H-NMR spectroscopy. The influence of EDTA on the 31P-NMR line width appeared to be negligible, which is in agreement with the idea that AlMV does not 'swell' like several other RNA-containing plant viruses. 相似文献