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51.
Experiments were conducted on guinea pigs with the use of cell migration inhibition test of the peritoneal exudate; stimulation of a definite level of cell immunity in response to the administration of both live and of inactivated vaccine virus was shown. The results obtained are used for the interpretation of the action mechanism of the inactivated preparation in two-stage smallpox vaccination.  相似文献   
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The lipophilic components of the medicinal plant, the fireweed (Chamaenerion angustifolium), have been examined using the raw materials of a three-year harvest. Twenty eight aliphatic and six triterpene acids have been detected for the first time by chromatography—mass spectrometry analysis. It has been shown using the Ames test and the SOS chromotest that pomolic acid possesses no genotoxic and mutagenic properties.  相似文献   
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Compounds based on the 2,3-distyrylindole scaffold were found to exhibit bactericidal properties upon irradiation with white light. At the concentration of 1?μM, the lead compound 1 completely (ca. 109?CFU/mL) eradicated such Gram-positive organisms as S. aureus (MRSA, MSSA), E. faecalis (VRE), S. pyogenes and S. mutans when irradiated with white light for 2?min. At the concentration of 5?μM and in the presence of polymyxin E at non-bactericidal 1.25?μg/mL concentration, 1 also showed a 7-log to 9-log reductions in bacterial counts of such Gram-negative organisms as multi-drug resistant (MDR) A. baumannii, MDR P. aeruginosa, E. coli and Klebsiella pneumoniae (CRE: KPC and NDM-1), also when irradiated with white light for 2?min. The structure-activity relationship studies revealed that unsubstituted at benzene rings 2,3-distyrylindole 2 was most potent and gave a 5-order of magnitude eradication of a MRSA strain at the concentration of 30?nM upon irradiation with white light. Initial mechanistic experiments revealed the disruption of bacterial cell membrane, but indicated that singlet oxygen production, which is commonly associated with photodynamic therapy, may not play a role in the bactericidal effects of the 2,3-distyrylindoles.  相似文献   
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Using bromoantimonate (V) (N‐EtPy)[SbBr6] as an example, it is demonstrated that ABX6 compounds can form perovskite‐like 3D crystalline frameworks with short interhalide contacts, enabling advanced optoelectronic characteristics of these materials. The designed compound shows an impressive performance in planar junction solar cells delivering external quantum efficiency of ≈80% and power conversion efficiency of ≈4%, thus being comparable with the conventional perovskite material MAPbBr3. The discovery of the first perovskite‐like compound ABX6 exhibiting good photovoltaic performance opens wide opportunities for rational design of novel perovskite‐like semiconductor materials for advanced electronic and photovoltaic applications.  相似文献   
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A thermophilic, anaerobic, chemolithoautotrophic bacterium (strain SU872T) was isolated from a shallow-sea hydrothermal vent at Kunashir Island. The cells were motile, gram-negative, oval or rodshaped 0.5?0.6 μm thick and 1.5?2.0 μm long, occurring singly or in pairs. Strain SU872T grew at 50 to 79°C (optimum at 74°C), pH from 5.0 to 8.0 (optimum at 6.7?7.0), and NaCl concentration of 1.5–4.5%. Strain SU872T was able to grow by disproportionation of elemental sulfur, thiosulfate, or sulfite, with CO2/HCO3? as the sole carbon source. Growth was enhanced in the presence of ferrihydrite (poorly crystalline Fe(III) oxide) as as a sulfide-scavenging agent. Sulfate was not used as an electron acceptor. Growth also occurred with elemental sulfur, thiosulfate, or sulfite (but not sulfide) as electron donors and nitrate as an electron acceptor, with production of sulfate and ammonium. Analysis of the 16S rRNA gene sequence revealed 97.8% similarity between strain SU872T and the type strain Thermosulfurimonas dismutans S95T (phylum Thermodesulfobacteria). According to the results of DNA–DNA hybridization, the similarity of genomic DNA of the strains SU872T and T. dismutans S95T was 48%. Based on its phenotypic characteristics and the results of phylogenetic analysis, it is proposed to assign the isolate to a new species of the genus Thermosulfurimonas,—Thermosulfurimonas marina sp. nov., with the type strain SU872T (=DSM 104922T, =VKM B-3177T, =UNIQEM SU872T).  相似文献   
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According to one hypothesis, Parkinson’s disease pathogenesis is largely caused by dopamine catabolism that is catalyzed on mitochondrial membranes by monoamine oxidase. Reactive oxygen species are formed as a byproduct of these reactions, which can lead to mitochondrial damage followed by cell degeneration and death. In this study, we investigated the effects of administration of the mitochondrial antioxidant SkQ1 on biochemical, immunohistochemical, and behavioral parameters in a Parkinson-like condition caused by protoxin MPTP injections in C57BL/6 mice. SkQ1 administration increased dopamine quantity and decreased signs of sensory-motor deficiency as well as destruction of dopaminergic neurons in the substantia nigra and ventral tegmental area in mice with the Parkinson-like condition.  相似文献   
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