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311.
Mesial temporal lobe epilepsy (MTLE) is associated with severe neuronal death and reactive gliosis in hippocampus. However, the molecular mechanisms underlying these pathological changes remain unanswered. ERK has been reported chronically activated in reactive glia of human epileptic hippocampus. In the present study, we investigated which of the downstream signaling molecules of ERK would be involved in MTLE. Western blot analysis demonstrated that CREB and p90RSK were strongly activated in MTLE patients. Increase in the active forms of CREB and p90RSK resulted not only from the increase in their phosphorylation levels but also from the increase in the protein levels. Activation of CREB and p90RSK was noted in the whole subfields of hippocampus with Ammon's horn sclerosis (AHS) representing a distinctive cellular distribution. However, the common major change was present in proliferating reactive astrocytes. In contrast, their activation was not significant in adjacent temporal lobes despite the presence of a number of astrocytes expressing high levels of GFAP. Our results demonstrate that chronic activation CREB and p90RSK in the epileptic hippocampus may be closely associated with the histopathological changes of AHS. 相似文献
312.
Micellar electrokinetic chromatographic separation of theophylline and its analogues was investigated using sodium dodecyl sulphate (SDS) as a micellar phase. The effects of pH, micelle concentration, applied voltage and temperature on the separation and preliminary quantitative analysis were studied for the determination of theophylline in human plasma. The data indicate that this technique could be used as the reference or routine method of theophylline measurement in therapeutic drug monitoring. 相似文献
313.
David A. Babb Richard A. Bartsch James J. Collier Dhimant H. Desai Sadik Elshania Mi‐Ja Goo Johnny L. Hallman Gwi Suk Heo Xiaowu Huang Vincent J. Huber Hong‐Sik Hwang Russell J. Johnson Yung Liu Michael J. Pugia Qiang Zhao 《Journal of heterocyclic chemistry》2004,41(5):659-675
Structurally related dibenzo‐16‐crown‐5 lariat ethers with pendant ester and ether groups are prepared. Structural variations within the series of alkyl lariat ether esters include changes in the O‐alkyl group, attachment site and nature of the lipophilic group, and length of the spacer, which connects the ester group to the polyether framework. Also synthesized are bis(crown ether) diesters with two dibenzo‐16‐crown‐5 or two dicyclohexano‐16‐crown‐5 units and two ester groups connected to each other by a linker of varying length. Synthetic strategies for the preparation of these lariat ethers with pendant ester‐ and ether‐containing side arms are described. 相似文献
314.
2-Bromobenzaldehydes react with arylhydrazines in toluene at 100 [degree]C in the presence of a catalytic amount of a palladium catalyst and phosphorus chelating ligands such as 1,1[prime or minute]-bis(diphenylphosphino)ferrocene and 1,3-bis(diphenylphosphino)propane along with NaO-t-Bu to afford 1-aryl-1H-indazoles in good yields. 相似文献
315.
Mid-infrared light emission characteristics of Ho3+-doped chalcogenide and heavy-metal oxide glasses
Emission characteristics of Ho3+-doped heavy-metal oxide and chalcogenide glasses were investigated and compared with those of conventional oxide glasses. In addition to the fluorescence at approximately 1.2 m (5/6 5/8) and 2.0 m (5/7 5/8), another mid-infrared emission was observed at 2.9 m from the transition 5/6 5/7. The calculated radiative transition probability and multiphonon decay rate of the latter transition using Judd-Ofelt analysis indicated that the occurrence of the 2.9 m fluorescence was directly related to the low vibrational phonon energy of the host glasses. 相似文献
316.
Shu-Sen Xie Sunyeong Heo Seokchan Kim Gyungsoo Woo Sucheol Yi 《Journal of Computational and Applied Mathematics》2008
This paper presents a numerical method for one-dimensional Burgers’ equation by the Hopf–Cole transformation and a reproducing kernel function, abbreviated as RKF. The numerical solution is given as explicit integral expressions with the RKF at each time step, so that the computation is fully parallel. The stability and error estimates are derived. Numerical results for some test problems are presented and compared with the exact solutions. Some numerical results are also compared with the results obtained by other methods. The present method is easily implemented and effective. 相似文献
317.
Si Hyun Kim Byoungsang Lee Jun Hyuk Heo Kyung Eun Lee Prabakaran Shankar Kwon‐Hoon Han Jung Heon Lee 《Particle & Particle Systems Characterization》2019,36(1)
The ζ‐potential and hydrodynamic size (dh) of nanoparticles (NPs) are systematically controlled by capping gold NPs (AuNPs) with polymers having different charges and treating them in NaCl solutions of diverse concentrations. Interactions between AuNPs in hydrogel are caused by chemical reactions induced by 1,4‐dithiothreitol. The effect of ζ‐potential is clear, as negatively charged AuNPs can be aggregated in neutral agarose gel, but the amount of aggregation is significantly affected by the magnitude of the negative surface charge on the AuNPs. However, all positively charged AuNPs show negligible aggregation in agarose gel with slightly negative polarity. The effect of dh on AuNP aggregation is different from that of ζ‐potential. Although AuNPs with small dh generally show more aggregation than those with large dh, the amount of AuNP capping layer is critical. Thus, the amount of polymer present on NP surface needs to be considered to investigate the effect of dh on AuNP aggregation. Through extended Derjaguin, Landau, Verwey, Overbeek (XDLVO) theory, it is shown that the charges of the AuNPs and the hydrogel, as well as the dh of the NPs, are related to electrostatic repulsion and steric hindrance, which affect AuNP aggregation in hydrogel. 相似文献
318.
Jaeseong Heo 《Israel Journal of Mathematics》2000,118(1):125-146
The definition of a completely positive invariant multilinear map from aC*-algebra to another is introduced. We construct the representation of a completely positive invariant multilinear map on
a HilbertC*-module without the bridging maps. This is another extension of the Stinespring’s representation, which is different from
a multilinear representation of Christensen and Sinclair. We give the covariant representation of completely positive invariant
covariant multilinear maps on a HilbertC*-module. Further, we investigate the order structure of such maps and obtain a generalization of the Radon-Nikodym theorem.
Partially supported by GARC-KOSEF. 相似文献
319.
Actively phase-locked heterodyne-detected fifth-order nonresonant Raman scattering from room temperature CS2 has been measured. The experimental signals have similar magnitudes, shapes, and sign changes as calculated responses obtained via molecular dynamics simulations [S. Saito and I. Ohmine, Phys. Rev. Lett. 88, 207401 (2002)]. The measured signals contain sign changes that appear to be associated with the coupling of rotational motions both to each other and to translational motions. 相似文献
320.