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1.
Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 5, 11–13, May, 1991.  相似文献   
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A method has been developed for assay of deoxynivalenol (DON) and its metabolite desepoxideoxynivalenol (DOM-1) in animal excrements with the use of reversed-phase high-performance liquid chromatography with UV-detection (218 nm). The method includes purification in the mini-column with activated carbon and aluminium oxide. The detection limit was 50 ng/g, relative standard deviation--0.05-0.1, the degree of toxin isolation--76-89%. DON isolated from Fusarium macroceras, strain 579a, cultivated in rice under laboratory conditions, and DOM-1 obtained as a result of DON incubation with the contents of the beef first stomach, were used in the study. The structure of toxins isolated has been proved by the mass-spectrometry method. The method developed by the authors was used in the study of DON metabolism in vivo in monkeys.  相似文献   
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The kinetics of radiation, thermal, and radiation–thermal decomposition of a mixture of nitric and acetic acids in water solutions of sodium nitrate is investigated under homogeneous conditions and with a solid phase introduced in the form of sandstone. The experimental data are used to calculate the temperature dependences of the rate of radiation, thermal, and radiation–thermal decomposition of the acids. The results obtained make it possible to calculate the dynamics of decomposition of acids for the conditions of deep burial of liquid radioactive wastes.  相似文献   
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Main Science Center of the Russian Federation, A. A. Bochvara All-Russia Scientific-Research Institute of Standardization in Machine Engineering. Atomnaya énergiya, Vol. 79, No. 3, pp. 197–200, September, 1995.  相似文献   
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Transplantation of various types of stem cells as a possible therapy for stroke has been tested for years, and the results are promising. Recent investigations have shown that the administration of the conditioned media obtained after stem cell cultivation can also be effective in the therapy of the central nervous system pathology (hypothesis of their paracrine action). The aim of this study was to evaluate the therapeutic effects of the conditioned medium of hiPSC-derived glial and neuronal progenitor cells in the rat middle cerebral artery occlusion model of the ischemic stroke. Secretory activity of the cultured neuronal and glial progenitor cells was evaluated by proteomic and immunosorbent-based approaches. Therapeutic effects were assessed by overall survival, neurologic deficit and infarct volume dynamics, as well as by the end-point values of the apoptosis- and inflammation-related gene expression levels, the extent of microglia/macrophage infiltration and the numbers of formed blood vessels in the affected area of the brain. As a result, 31% of the protein species discovered in glial progenitor cells-conditioned medium and 45% in neuronal progenitor cells-conditioned medium were cell type specific. The glial progenitor cell-conditioned media showed a higher content of neurotrophins (BDNF, GDNF, CNTF and NGF). We showed that intra-arterial administration of glial progenitor cells-conditioned medium promoted a faster decrease in neurological deficit compared to the control group, reduced microglia/macrophage infiltration, reduced expression of pro-apoptotic gene Bax and pro-inflammatory cytokine gene Tnf, increased expression of anti-inflammatory cytokine genes (Il4, Il10, Il13) and promoted the formation of blood vessels within the damaged area. None of these effects were exerted by the neuronal progenitor cell-conditioned media. The results indicate pronounced cytoprotective, anti-inflammatory and angiogenic properties of soluble factors secreted by glial progenitor cells.  相似文献   
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It was shown that in going from the mesomorphic γ-modification of PA-6 to the stable α-form, formation of intermediate structures can play an important role. It was found that the formation of the polymorphous α-modification in conditions of heat treatment at 180°C takes place due to the amorphous regions of the polymer. __________ Translated from Khimicheskie Volokna, No. 6, pp. 15–17, November–December, 2007.  相似文献   
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The mechanical properties of single crystals of alloy ZhS32 at a temperature of 1150–1250°C and deformation rates of 3 × 10−5, 10−4, and 10−3 sec−1 are studied. The characteristics of true ductility in tests for long-term strength in a temperature range of 1150–1250°C are determined. __________ Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 1, pp. 38–40, January, 2006.  相似文献   
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