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81.
A. V. Ruseikina L. A. Solovyov M. S. Molokeev O. V. Andreev 《Russian Journal of Inorganic Chemistry》2012,57(1):79-83
The compound sulfides EuLnCuS3 (Ln = Nd and Sm) were obtained for the first time. Their crystal structures were determined from X-ray powder diffraction data. The crystals of both compounds are orthorhombic (space group Pnma). The compound EuNdCuS3 is isostructural with BaLaCuS3; the unit cell parameters are a = 11.0438(2) Å, b = 4.0660(1) Å, c = 11.4149(4) Å. The compound EuSmCuS3 is isostructural with Eu2CuS3; the unit cell parameters are a = 10.4202(2) Å, b = 3.9701(1) Å, c = 12.8022(2) Å. 相似文献
82.
Altun M Kramer HB Willems LI McDermott JL Leach CA Goldenberg SJ Kumar KG Konietzny R Fischer R Kogan E Mackeen MM McGouran J Khoronenkova SV Parsons JL Dianov GL Nicholson B Kessler BM 《Chemistry & biology》2011,18(11):1401-1412
Converting lead compounds into drug candidates is a crucial step in drug development, requiring early assessment of potency, selectivity, and off-target effects. We have utilized activity-based chemical proteomics to determine the potency and selectivity of deubiquitylating enzyme (DUB) inhibitors in cell culture models. Importantly, we characterized the small molecule PR-619 as a broad-range DUB inhibitor, and P22077 as a USP7 inhibitor with potential for further development as a chemotherapeutic agent in cancer therapy. A striking accumulation of polyubiquitylated proteins was observed after both selective and general inhibition of cellular DUB activity without direct impairment of proteasomal proteolysis. The repertoire of ubiquitylated substrates was analyzed by tandem mass spectrometry, identifying distinct subsets for general or specific inhibition of DUBs. This enabled identification of previously unknown functional links between USP7 and enzymes involved in DNA repair. 相似文献
83.
Effect of conditions of deposition of palladium onto a composite polymeric film Nafion—polyaniline on the properties of the system thus obtained is studied. It is shown that the effect of the said conditions on the character of distribution of palladium in a polymer may be used when estimating electrocatalytic potentialities of such composites.Translated from Elektrokhimiya, Vol. 41, No. 2, 2005, pp. 213–218.Original Russian Text Copyright © 2005 by Andreev, Zolotarevskii.This revised version was published online in April 2005 with corrections to the article note and article title and cover date. 相似文献
84.
由于抗生素的不当使用和细菌多药耐药的出现, 迫切需要开发新的抗菌剂. 本文制备了具有光热转换性能的正电荷半导体高分子材料及具有协同抗菌活性的半导体聚合物纳米粒子(SP-PPh3 NPs). SP-PPh3 NPs的光热转化效率为43.8%. 带正电荷的SP-PPh3 NPs可以附着在细菌上, 有助于将热量有效传递给细菌. 在热和正电荷的协同作用下, SP-PPh3 NPs对革兰氏阴性大肠杆菌(E. coli)和革兰氏阳性金黄色葡萄球菌(S. aureus)均具有抗菌活性, 其对二者的体外抑菌率分别为99.9%和98.6%. 此外, SP-PPh3 NPs具有良好的生物相容性, 对小鼠的主要器官几乎无副作用. 对细菌感染的小鼠皮肤伤口用SP-PPh3 NPs治疗12 d后, 伤口可以很好地愈合. 相似文献
85.
Fedoseev A. M. Budantseva N. A. Andreev G. B. Yusov A. B. Shirokova I. B. 《Russian Journal of Coordination Chemistry》2002,28(4):279-284
The reactions of some rare-earth elements (La, Ce, Sm, Lu, Gd) and Am(III) with heteropolymolybdate anions are studied. The complexation rate constants of Am(III) in a solution with Al(OH)6Mo6O18
3- and Cr(OH)6MoO18
3-
6 (1 = 18 ± 6 and 25 ± 5, respectively) are determined by spectral methods. The Ln[Al(OH)6Mo6O18] · nH2O, Eu[Cr(OH)6Mo6O18] · nH2O, and Am[Al(OH)6Mo6O18] · nH2O isostructural compounds are synthesized. The crystal structure of the Sm[Al(OH)6Mo6O18] · 11H2O complex was determined by the X-ray diffraction analysis. The results of spectroscopic and thermogravimetric studies of the obtained compounds are presented. 相似文献
86.
87.
We consider a method of detecting the ionizing component of solar cosmic rays (SCRs) with energy from tens of MeV to tens of GeV by measuring the energy loss of SCR protons and light nuclei in scintillators and the multiplicity of the local neutron generation in a converter. Scintillation detectors based on stilbene, lithium glass, and solid-state photomultiplier tubes are capable of detecting fast neutrons with a temporal resolution of 10 ns and rejecting the gamma-ray background in the measuring system. The method will allow investigating the nucleon components of primary SCRs in circumterrestrial space. 相似文献
88.
V. B. Petkov E. V. Bugaev P. A. Klimai M. V. Andreev V. I. Volchenko G. V. Volchenko I. M. Dzaparova D. D. Dzhappuev A. N. Gaponenko Zh. Sh. Guliev N. F. Klimenko A. U. Kudzhaev A. V. Sergeev N. S. Khaerdinov A. B. Chernyaev A. F. Yanin 《Journal of Experimental and Theoretical Physics》2010,110(3):406-416
The energy spectra and temporal characteristics of high-energy gamma-ray bursts from evaporating primordial black holes have been calculated using various evaporation models. The currently existing theoretical uncertainties in the shape of the evaporated photon spectrum are discussed. The data from the Andyrchy and Carpet-2 arrays of the Baksan Neutrino Observatory (Institute for Nuclear Research, Russian Academy of Sciences) obtained in the mode of detection of a single cosmic-ray component are used to search for cosmic gamma-ray bursts with a primary photon energy of about 8 GeV. New upper limits have been obtained for the number density of evaporating black holes in a local region of space with a characteristic size of ~10?3 pc for various evaporation models. 相似文献
89.
Mario Thevis Ines Möller Andreas Thomas Simon Beuck Grigory Rodchenkov Wolfgang Bornatsch Hans Geyer Wilhelm Schänzer 《Analytical and bioanalytical chemistry》2010,396(7):2479-2491
Since January 2009, the list of prohibited substances and methods of doping as established by the World Anti-Doping Agency
includes new therapeutics such as the peroxisome-proliferator-activated receptor (PPAR)-delta agonist GW1516, which is categorized
as a gene doping substance. GW1516 has completed phase II and IV clinical trials regarding dyslipidemia and the regulation
of the lipoprotein transport in metabolic syndrome conditions; however, its potential to also improve athletic performance
due to the upregulation of genes associated with oxidative metabolism and a modified substrate preference that shifted from
carbohydrate to lipid consumption has led to a ban of this compound in elite sport. In a recent report, two presumably mono-oxygenated
and bisoxygenated urinary metabolites of GW1516 were presented, which could serve as target analytes for doping control purposes
after full characterization. Hence, in the present study, phase I metabolism was simulated by in vitro assays employing human
liver microsomal fractions yielding the same oxygenation products, followed by chemical synthesis of the assumed structures
of the two abundant metabolic reaction products. These allowed the identification and characterization of mono-oxygenated
and bisoxygenated metabolites (sulfoxide and sulfone, respectively) as supported by high-resolution/high-accuracy mass spectrometry
with higher-energy collision-induced dissociation, tandem mass spectrometry, and nuclear magnetic resonance spectroscopy.
Since urine samples have been the preferred matrix for doping control purposes, a method to detect the new target GW1516 in
sports drug testing samples was developed in accordance to conventional screening procedures based on enzymatic hydrolysis
and liquid–liquid extraction followed by liquid chromatography, electrospray ionization, and tandem mass spectrometry. Validation
was performed for specificity, limit of detection (0.1 ng/ml), recovery (72%), intraday and interday precisions (7.7–15.1%),
and ion suppression/enhancement effects (<10%). 相似文献
90.
The rates of hydrogen penetration from an aqueous solution of glycerin into thin films of vanadium dioxide in different phases
have been compared. It has been found that the rate of hydrogen penetration into the metal phase of vanadium dioxide is at
least one order of magnitude higher than that of hydrogen penetration into the semiconductor phase at the same temperature. 相似文献