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排序方式: 共有1704条查询结果,搜索用时 15 毫秒
71.
Bin Qiu Susan E. Luczak Tamara L. Wall Aaron M. Kirchhoff Yuxue Xu Mimy Y. Eng Robert B. Stewart Weinian Shou Stephen L. Boehm II Julia A. Chester Weidong Yong Tiebing Liang 《International journal of molecular sciences》2016,17(8)
FKBP5 encodes FK506-binding protein 5, a glucocorticoid receptor (GR)-binding protein implicated in various psychiatric disorders and alcohol withdrawal severity. The purpose of this study is to characterize alcohol preference and related phenotypes in Fkbp5 knockout (KO) mice and to examine the role of FKBP5 in human alcohol consumption. The following experiments were performed to characterize Fkpb5 KO mice. (1) Fkbp5 KO and wild-type (WT) EtOH consumption was tested using a two-bottle choice paradigm; (2) The EtOH elimination rate was measured after intraperitoneal (IP) injection of 2.0 g/kg EtOH; (3) Blood alcohol concentration (BAC) was measured after 3 h limited access of alcohol; (4) Brain region expression of Fkbp5 was identified using LacZ staining; (5) Baseline corticosterone (CORT) was assessed. Additionally, two SNPs, rs1360780 (C/T) and rs3800373 (T/G), were selected to study the association of FKBP5 with alcohol consumption in humans. Participants were college students (n = 1162) from 21–26 years of age with Chinese, Korean or Caucasian ethnicity. The results, compared to WT mice, for KO mice exhibited an increase in alcohol consumption that was not due to differences in taste sensitivity or alcohol metabolism. Higher BAC was found in KO mice after 3 h of EtOH access. Fkbp5 was highly expressed in brain regions involved in the regulation of the stress response, such as the hippocampus, amygdala, dorsal raphe and locus coeruleus. Both genotypes exhibited similar basal levels of plasma corticosterone (CORT). Finally, single nucleotide polymorphisms (SNPs) in FKBP5 were found to be associated with alcohol drinking in humans. These results suggest that the association between FKBP5 and alcohol consumption is conserved in both mice and humans. 相似文献
72.
Melt spun matrix fibers of toughened polypropylene copolymers modified by high energy electrons 下载免费PDF全文
Binary blends of polypropylene (PP) and ethylene‐octene copolymer (EOC) are prepared by continuous electron‐induced reactive processing at various mass ratios of the blend components and various doses without adding of any grafting agents. The influence of mass ratio and dose is investigated in order to get the optimum processing behavior of toughened PP as well as optimum properties of resulting fibers. It is found that toughened PP with a PP/EOC blend ratio of 97.5–2.5 mass % can be used advantageously as a matrix component for the process of online spinning of glass fiber/toughened PP hybrid yarns. Such hybrid yarns belong to one of the most advanced production methods for the manufacturing of fiber reinforced thermoplastic composites with an increased mechanical performance. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44011. 相似文献
73.
Przemyslaw Krause Lutz Hilterhaus Georg Fieg Andreas Liese Uwe Bornscheuer 《European Journal of Lipid Science and Technology》2009,111(2):194-201
The esterification of benzoic acid with n‐hexanol, n‐octanol, 2‐ethyl hexanol and n‐decanol was investigated in detail. An analysis of the reaction kinetics of esterification in the presence of different commercially available chemical catalysts was carried out. The effects of catalyst type and loading on the reaction rate were studied. Although the considered reaction is bimolecular, it showed a first‐order behavior, and a linear dependence with respect to the catalyst concentration was observed. Hence, a new approach is presented to describe the reaction kinetics accurately over a wide range. The application of biotechnological synthesis applying different enzymes as catalysts offers an interesting alternative besides chemical synthesis. Especially an esterase from Bacillus subtilis immobilized on Sepabeads EC‐EP showed high stability and was applied for 2 days in the synthesis of hexyl benzoate. Nevertheless, the chemical reaction route remains superior with respect to the catalyst activities under the applied conditions, which were 25 kU/g for the chemical reaction and 0.7 kU/g for the best enzymatic conversion. 相似文献
74.
Jens‐Uwe Peters Dr. Patrick Schnider Dr. Patrizio Mattei Dr. Manfred Kansy Dr. 《ChemMedChem》2009,4(4):680-686
What parameters determine promiscuity? A compound's potential for promiscuity (pharmacological activity at multiple targets) may be influenced by molecular parameters such as ionization state, lipophilicity, and molecular weight. In an analysis of recent Roche compounds we found that a positive charge is an important determinant for potential promiscuity; aminergic activity was found to be the main reason for overt promiscuity.
75.
This study concerns with the investigation of the effect of irradiation conditions on grafting of styrene into FEP films by the pre‐irradiation method. EPR spectroscopy was used to characterize the base polymer material regarding the trapped radical species and their concentration. Radiation‐induced changes in the chemical structure were studied by IR spectroscopy. Tensile strength and elongation at break as well as yield of grafting were found to be strongly influenced by irradiation temperature. Main‐chain scissions were identified to be the reason for the deterioration of the mechanical properties after radiation treatment at temperatures below glass transition temperature.
76.
To increase the applicability of carbon nanotubes (CNTs) oxygen-containing functional groups were generated on their widely inert surface by using glow-discharge plasmas. CNT-sheets (bucky papers) produced from the powder-like raw material were used as substrates allowing for a more defined characterization of one and the same surface by different analytical techniques. The plasma composition was analyzed by optical emission spectroscopy. Since the actual composition of the plasma-induced functional groups has still not been completely resolved, we performed an in-depth characterization of the treated samples by X-ray photoelectron (XPS) and Raman spectroscopy as well as electron spin resonance measurements. To overcome limitations of the XPS-analysis in distinguishing between groups featuring nearby binding energies, alcohol-, keto-/aldehyde-, and carboxyl-groups were tagged by derivatization techniques using fluorine-containing reagents (trifluoroaceticanhydride, trifluoromethylphenylhydrazine, and trifluoroethanol). Differential spectra were calculated to enhance the accuracy of the deconvolution of the XPS-spectra. This enabled us to determine dependencies of the plasma parameters, i.e. treatment time, process pressure, and gas composition (mixtures of Ar, O2, H2O, and H2), on the composition of the generated functional groups as well as an up to 6-fold enhancement in derivatizable groups for switching process gas from Ar/O2 to Ar/H2O. 相似文献
77.
Heijari J Nerg AM Kainulainen P Noldt U Levula T Raitio H Holopainen JK 《Journal of chemical ecology》2008,34(1):26-31
We tested whether changes in long-term nutrient availability would affect the xylem quality and characteristics of Scots pine
trees as a food source for the larvae of the xylophagous wood borer Hylotrupes bajulus L. (Cerambycidae). We looked for an effect of host plant growth and xylem structural traits on H. bajulus larval performance, and looked for delayed effects of long-term forest fertilization on xylem chemical quality. In general,
larval performance was dependent on larval developmental stage. However, the growth of larvae also varied with host plant
quality (increases in the concentration of nitrogen and carbon-based secondary compounds of xylem were correlated with a decrease
in the larval growth rate). The greater annual growth of trees reduced tracheid length and correlated positively with second-instar
H. bajulus growth rate. This is consistent with the hypothesis that intrinsic growth patterns of host plants influence the development
of the xylophagous wood borer H. bajulus. 相似文献
78.
Christoph Windmeier Felix Flegiel Alexander Döß Ronald Franz Eckhard Schleicher Michael Wiezorek Markus Schubert Uwe Hampel 《化学,工程师,技术》2021,93(7):1119-1125
An optimized equipment design for natural gas processing and liquefaction plants becomes increasingly difficult with changing process conditions: Particularly low values of surface tension create rising challenges on the design of phase separators and column internals. The TERESA test rig at HZDR was designed to allow the investigation of multiphase thermohydraulics and phase separator performance under critical fluid properties in industrial dimensions. A versatile pipe test section is available in DN200 and equipment internals may be tested in a sectional DN300/DN500 test separator. The applied test fluid shows a high vapor-liquid density difference between 1470 and 940 kg m−3, viscosity as low as 0.12 mm2s−1, and surface tension down to 1.3 mN m−1. Volumetric liquid and vapor flow rates may be varied up to 9 and 530 m3h−1 in the test rig, respectively. 相似文献
79.
Alexander Döß Markus Schubert Michael Wiezorek Uwe Hampel Felix Flegiel Christoph Windmeier Eckhard Schleicher Christoph Schunk 《化学,工程师,技术》2021,93(7):1126-1133
Tailored conditioning and control of flashing feeds in industrial applications requires knowledge of the evolving flow morphology and phase fractions along the feed pipe. Design methods obtained from reference systems (e.g. water-air) are hardly applicable for commercial scales and critical fluid properties (e.g. high vapor densities, low surface tension). In this study, the flow morphology of flashing feeds in a novel refrigerant test rig at critical fluid properties was analyzed using wire-mesh sensors at two locations along the feed pipe and experimental data from the water-air system. 相似文献
80.
Dr. Ana G. Enderle Dr. Matteo Bosso Rüdiger Groß Magdalena Heiland Dr. Mariela Bollini Dr. María J. Culzoni Prof. Dr. Frank Kirchhoff Prof. Dr. Jan Münch Prof. Dr. Carsten Streb 《ChemMedChem》2021,16(17):2727-2730
Polyoxometalates (POMs), molecular metal oxide anions, are inorganic clusters with promising antiviral activity. Herein we report increased anti-HIV-1 activity of a POM when electrostatically combined with organic counter-cations. To this end, Keggin-type cerium tungstate POMs have been combined with organic methyl-caffeinium (Caf) cations, and their cytotoxicity, antiviral activity and mode of action have been studied. The novel compound, Caf4K[β2-CeSiW11O39]×H2O, exhibits sub-nanomolar antiviral activity and inhibits HIV-1 infectivity by acting on an early step of the viral infection cycle. This work demonstrates that combination of POM anions and organic bioactive cations can be a powerful new strategy to increase antiviral activity of these inorganic compounds. 相似文献