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排序方式: 共有98条查询结果,搜索用时 15 毫秒
1.
Alick KT Law Deepak Gupta Shawn Levy Douglas C Wallace Robert J McKeon Charles R Buck 《BMC neuroscience》2004,5(1):1
Background
The adenine nucleotide translocator 1 (Ant1) is an inner mitochondrial membrane protein involved with energy mobilization during oxidative phosphorylation. We recently showed that rodent Ant1 is upregulated by transforming growth factor-beta (TGF-β) in reactive astrocytes following CNS injury. In the present study, we describe the molecular mechanisms by which TGF-β1 regulates Ant1 gene expression in cultured primary rodent astrocytes. 相似文献2.
Summary We deal with two diffusion problems: Space-integrated conserved entities characterizing very fast - diffusion - controlled reactions, such as time lags, etc. are universal. They are given by relationships which do not reflect the failure of the mean field hydrodynamic equations. We present another application which does not reflect this failure, for determining the surface flux via a diffusion controlled reaction producing a colored product. Another anomalous diffusion process we considered is transport through cellular materials whose cell sizes are highly nonuniform. We have analyzed the effects of extreme nonuniformity by considering fractal-like models of cellular solids. The diffusion current through these models can exhibit anomalous time-dependencies which are not predicted by the diffusion equation. In particular, it is shown that the initial diffusion current can be characterized by a power-law dependence on the time. Furthermore, the exponent of the power law is given in terms of the distribution of cell sizes in the fractal-like cellular solid. 相似文献
3.
High-temperature intramolecular cyclization of N, N-dialkyl-N'-(4-substituted-2-ethynylphenyl)triazenes provides under neutral conditions both 6-substituted cinnolines and 5-substituted isoindazoles in moderate to excellent yields. 相似文献
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5.
R. R. Mendel Kimball A. Milton James H. Reid Mark A. Samuel 《Zeitschrift fur Physik C Particles and Fields》1986,32(4):517-520
Several methods to determine (or set an upper bound on) the mass of the tau neutrino are described. The decay spectrum of \(\tau \to e\bar \nu _e \nu _\tau \) near the high center-of-mass electron-energy end is particularly sensitive to the tau-neutrino mass. It is shown that an upper bound of 20 MeV or lower may be feasible. In addition, improved limits on the mass and mixing angle of a heavy component of the tau-neutrino may be readily obtained. We also discuss the purely leptonic decays of theD andF mesons, and show how measurements of the ratiosB(D→τντ/B(D→μνμ,B(F→τντ/B(D→μνμ can be sensitive to tau-neutrino masses of 30 MeV or greater. 相似文献
6.
Kimball DB Haley MM Mitchell RH Ward TR Bandyopadhyay S Williams RV Armantrout JR 《The Journal of organic chemistry》2002,67(25):8798-8811
The synthesis and study of dehydrobenzoannulene (DBA)-dimethyldihydropyrene (DDP) hybrids as models for the investigation of aromaticity in weakly diatropic systems is reported. Three new monofused DBA-DDP hybrids have been synthesized, and their NMR spectra are discussed with regard to quantifying the aromaticity remaining in multibenzene-fused DBAs. Nucleus-independent chemical shifts, determined at a series of locations for each compound, bond lengths, and (1)H and (13)C NMR chemical shifts were calculated and used to probe the aromaticity of these hybrids. Systems where more than one annulene/DBA is fused to the DDP core have also been obtained, and their potential use in photoinduced isomerization applications is discussed. 相似文献
7.
The cyclization of (2-ethynylphenyl)triazenes in ODCB at 200 degrees C gives exclusively cinnolines, whereas addition of CuCl to 1,2-dichloroethane solutions of the triazenes at 50 degrees C results in the sole formation of isoindazoles. DFT calculations and deuterium labeling studies suggest the intermediacy of a 3-dehydrocinnolinium ion, produced through a pericyclic transition state. Calculations and trapping studies strongly implicate a carbene intermediate in isoindazole formation, which proceeds through a pseudocoarctate transition state. 相似文献
8.
9.
Slow light is demonstrated in liquid phase in an aqueous bacteriorhodopsin (bR) solution at room temperature. Group velocity as low as 3 m/s (all the way to c) is achieved by exploiting the photoisomerization property of bR for coherent population oscillations. Slow light in the liquid phase offers several advantages over solids or vapors for a variety of applications: (i) shorter lifetimes of the M state facilitate slow light at higher modulation frequencies, (ii) convection makes it possible to obtain large signal delays even at high input powers, and (iii) solution concentration is another convenient parameter to vary the signal delay over a wide range. 相似文献
10.
A new route to isoindazoles and cinnolines through the cyclization of (2-alkynylphenyl)triazenes under neutral conditions is presented. The products that result from heating the starting triazenes depend on both the type of alkyne ortho to the triazene functionality and the temperature used. Butadiyne moieties ortho to dialkyltriazenes yield bis-isoindazole dimers when heated to 150 degrees C in MeI. A requirement for cyclization in MeI is that the (2-alkynylphenyl)triazene must contain a suitably electron-withdrawing substituent on the phenyl ring to deactivate the triazene toward methylation-induced decomposition to an iodoarene. Ethynyl moieties ortho to dialkyltriazenes yield both isoindazole dimers as well as 3-formylisoindazoles when subjected to the same conditions. Replacing MeI with 1,2-dichlorobenzene as solvent allows for the general cyclization of (2-ethynylphenyl)dialkyltriazenes. Heating to 170 degrees C results in a mixture of isoindazole and cinnoline products, whereas the cinnolines are produced exclusively in high yield at 200 degrees C. Alternatively, the isoindazoles can be obtained in good to excellent yield by stirring a 1,2-dichloroethane solution of the starting triazene with CuCl overnight at 50 degrees C. 相似文献