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排序方式: 共有208条查询结果,搜索用时 9 毫秒
91.
92.
YoungKwan Park SangBeom Choi Hyunuk Kim Kimoon Kim Byoung‐Ho Won Kihang Choi Jung‐Sik Choi Wha‐Seung Ahn Nayoun Won Sungjee Kim DongHyun Jung Seung‐Hoon Choi Ghyung‐Hwa Kim Sun‐Shin Cha YoungHo Jhon JinKuk Yang Jaheon Kim 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2007,119(43):8378-8381
93.
Young Su Jung Ha Young Lee Sang Doo Kim Joon Seong Park Jung Kuk Kim Pann-Ghill Suh Yoe-Sik Bae 《Experimental & molecular medicine》2013,45(6):e27
Wnt5a is a ligand that activates the noncanonical Wnt signaling pathways (β-catenin-independent pathways). Human neutrophils expressed several Wnt5a receptors, such as Frizzled 2, 5 and 8. Stimulation of human neutrophils with Wnt5a caused chemotactic migration and the production of two important chemokines, CXCL8 and CCL2. CCL2 production by Wnt5a was mediated by a pertussis toxin-sensitive G-protein-dependent pathway. Wnt5a also stimulated the phosphorylation of three mitogen-activated protein kinases (MAPKs: ERK, p38 MAPK and JNK) and Akt. Inhibition of ERK, p38 MAPK or JNK by specific inhibitors induced a dramatic reduction in Wnt5a-induced CCL2 production. Supernatant collected from lipopolysaccharide-stimulated macrophages induced neutrophil chemotaxis, which was significantly inhibited by anti-Wnt5a antibody. Our results suggested that Wnt5a may contribute to neutrophil recruitment, mediating the inflammation response. 相似文献
94.
95.
96.
Kee?Sung?LeeEmail author Shiwoo?Lee Ji?Haeng?Yu Doo?Won?Seo Sang?Kuk?Woo 《Journal of Solid State Electrochemistry》2007,11(9):1295-1301
Improvement of long-term stability of 40vol.%NiO–60vol.% yttria-stabilized zirconia (YSZ) anode material in reducing atmosphere
and under exposure to thermal shock through the modification of vacancy concentration and pore shape has been investigated
for a solid oxide fuel cell. We varied the amount of Y2O3 additives from 8 to 10 mol% in YSZ and the type of carbon pore former, from plated activated carbon to spherical carbon black,
to improve the strength and the stability of porous NiO–YSZ anode materials. Modifications by varying the amount of Y2O3 additives and carbon pore former result in a highly stable anode, even upon exposure to a reducing atmosphere for 1,200 h.
In particular, the strengths of the new anode materials are markedly improved at the same porosity level. Higher strengths
do not degrade during a longtime durability test in a reducing atmosphere or upon thermal shock testing. The relatively smaller
degradation of electrical conductivity of the new anode material is discussed in terms of the possibility of suppression of
the disconnectivity of Ni phases during operation of a solid oxide fuel cell. 相似文献
97.
Charge transfer (CT) resonance mechanisms of 2,2′‐bipyridine (2,2′‐BiPy), 2,4′‐bipyridine (2,4′‐BiPy), and 4,4′‐bipyridine (4,4′‐BiPy) on silver nanoparticle surfaces have been comparatively investigated by means of surface‐enhanced Raman scattering (SERS) at the excitation wavelengths of 457, 514, 633, and 785 nm. A combination of the electromagnetic (EM) and charge transfer (CT) contributions should affect the SERS intensities for the bipyridine compounds adsorbed on silver nanoparticle surfaces. The CT resonance is assumed to occur in dissimilar ways for the bipyridine compounds, as evidenced from their different excitation‐wavelength‐dependent SERS enhancement factors. Ab initio density functional theory (DFT) calculations at the level of B3LYP/LANL2DZ have been carried out for the bipyridine‐Ag complexes. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
98.
Kuk Young Cho Chang-Hyeon Kim Jong-Woo Lee Jung-Ki Park 《Macromolecular rapid communications》1999,20(11):598-601
Poly(ethylene glycol) grafted poly(L -lactide) was prepared by ring opening polymerization of L -lactide and epoxy-terminated poly(ethylene glycol) methyl ether (PEGME). Stannous octoate and Al(Et)3·0.5 H2O were tested as polymerization catalysts, and Al(Et)3·0.5 H2O was found to be more effective for the ring-opening of the epoxy group of the modified PEGME monomer. The synthesized polymers were characterized by NMR and the efficiency of the incorporation of epoxy-terminated PEGME in the copolymer was determined. 相似文献
99.
We propose a new procedure for testing hypotheses with the use of optimal statistical criteria.
Institute of Cybernetics, Ukrainian Academy of Sciences, Kiev. Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 49,
No. 8, pp. 1042–1054, August, 1997. 相似文献
100.
In this paper, we investigate the fault currents in an inductive high-Tc superconducting fault current limiter (SFCL). The currents can cause serious damage to the reliability and stability of the power system. To analyze the transient fault characteristics of the SFCL, we fabricated an inductive high-Tc SFCL and tested it under different fault conditions. To simulate a fault condition, a fault angle controller was connected to a load. As the firing angle of the triac in the fault angle controller was controlled, various angles of the fault instant can be selected. An important parameter for the design and the fabrication of the SFCL is the reduction of the fault currents. If abnormally high currents due to low impedance of SFCL do not occur in the network with SFCL, the currents flowing under fault conditions can be limited to a desired value within one cycle. The fault current reduction depends on saturation, normal zone propagation velocity, turns ratio, and the fault angle (the instant of the fault occurrence within a cycle) 相似文献