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91.
92.
A discussion is given of certain electromagnetic fields associated with charges moving with zero acceleration. These fields involve zero magnetic field and the creation of charge.  相似文献   
93.
ABM (3-aminobenzanthrrone derivative) developed at the Riga Technical University, Riga, Latvia) has been previously shown as a potential probe for determination of the immune state of patients with different pathologies .The fist study (using probe ABM) of peripheral blood mononuclear cells (PBMC) membranes of 97 Chernobyl clean-up workers from Latvia was conducted in 1997. Now we repeatedly examine the same (n = 54) individuals in dynamics. ABM spectral parameters in PBMC suspension, fluorescence anisotropy and blood plasma albumin characteristics were recorded. In 1997 screening showed 5 different patterns of fluorescence spectra, from which in 2007 we obtained only two. These patterns of spectra had never been previously seen in healthy individuals or patients with tuberculosis, multiple sclerosis, rheumatoid arthritis, etc., examined by us. Patterns of ABM fluorescence spectra are associated with membrane anisotropy and conformational changes of blood plasma albumin. We observed that in dynamics 1997–2007 the lipid compartment of the membrane became more fluid while the lipid-protein interface became more rigid. The use of probe ANS and albumin auto-fluorescence allowed show conformational alterations in Chernobyl clean-up workers blood plasma. It is necessary to note that all investigated parameters significantly differ in observed groups of patients. These findings reinforce our understanding that that the cell membrane is a significant biological target of radiation. The role of the membrane in the expression and course of cell damage after radiation exposure must be considered. So ten years dynamic of PBMC membrane characteristics by ABM (spectral shift and anisotropy indexes) in Chernobyl clean-up workers reveal progressive trend toward certain resemblance with those of chronic B-cell lymphoid leukemia.  相似文献   
94.
A new method is used for the separation of ethene secondary ozonide (SOZ) from the other products of ethene ozonization reaction. The reaction was performed in the neat films of the reactants at 77 K. Ethene SOZ was separated from other products of the reaction by vacuum distillation at 190–210 K and analyzed by means of the matrix isolation IR absorption spectroscopy. Spectroscopic data from photolysis of the matrix isolated ozonide was used as an argument for assignment of the infrared spectral bands either to ethene SOZ or to other products of the reaction. The spectra of ethene SOZ isolated in the Ar matrix were analyzed by combining experimental results with the theoretical calculations performed at the MP2 6-311+G (3df, 3pd) level. A new assignment of some experimental fundamental bands is proposed taking in to account the Fermi resonance between CH stretch and the five membered ring vibrations. For the first time more than 30 weak infrared absorption bands were observed and assigned to various combination vibrations and overtones. By using new spectral information concerning the overtones and the combination bands it is concluded that the dissociation of unstable ethene SOZ involving breaking of any of the four CO bonds of the five membered ring of ethene SOZ has low probability. Dissociation of the ring starts from breaking of the OO bond.   相似文献   
95.
Green tea extracts (GTEs) as well as their main component, the polyphenol epigallocatechin gallate (EGCG), are known for their versatile antioxidant, antimicrobial, antitumoral or anti-inflammatory effects. In spite of the huge beneficial action, there is increasing evidence that under certain conditions green tea and its components can be detrimental to living organisms. Using Saccharomyces cerevisiae strains with various defects in the response to oxidative stress, we found that GTEs or EGCG act in synergy with visible light, exhibiting either deleterious or protective effects depending on the solvent employed. Similar synergistic effects could be observed under singlet oxygen-generating conditions, such as light exposure in the presence of photosensitizers or UV-A irradiation, therefore solvent variance may represent a powerful tool to modulate the preparation of green tea extracts, depending on the intended target.  相似文献   
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