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排序方式: 共有3586条查询结果,搜索用时 15 毫秒
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Hongcheng Yang Miao Zhou Haodong Tang Mingyu Sun Pai Liu Yizun Liu Lixuan Chen Dongze Li Dan Wu Junjie Hao Bing Xu Zhili Zhao Zhenwei Ren Siqi Jia Kai Wang Xiao Wei Sun 《RSC advances》2020,10(53):31705
Quantum dots (QDs) have received considerable attention in information displays owing to their high quantum yield, high colour purity and low-cost fabrication. However, light emission for ultra-thin QD films with low mass percentage of QDs still need to be improved because the blue light can directly transmit the films, leading to insufficient energy to excite the QDs. In this study, we report QD films based on a poly(zinc methacrylate) coating with alloyed green-emitting CdZnSeS/ZnS quantum dots (QDs@PZnMA) together with high refractive-index BaTiO3 nanoparticles to enhance the scattering coefficient of the QD films. Results demonstrate a 7.5-fold increase in the absorption coefficient, 11.3-fold increase in the scattering coefficient, 8.5-fold increase in the optical density (OD) and 8.6-fold increase in the green-light emission of QD films, compared with films that have the same mass percentage of pristine QDs. This approach provides a promising strategy for developing QD optical films with high scattering and enhanced light emission for flexible displays.We report QD films based on a poly(zinc methacrylate) coating with alloyed green-emitting CdZnSeS/ZnS quantum dots (QDs@PZnMA) together with high refractive-index BaTiO3 nanoparticles to enhance the scattering coefficient of the QD films. 相似文献
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Involvement of guanine nucleotide binding proteins in neutrophil activation and priming by GM-CSF 总被引:4,自引:0,他引:4
Pre-incubation of human neutrophils with pertussis toxin significantly inhibited the neutrophil-directed biologic actions of granulocyte- macrophage colony-stimulating factor (GM-CSF) in three separate assays: the induction of c-fos mRNA, the enhancement of both platelet- activating factor-induced mobilization of intracellular calcium, and stimulation of leukotriene synthesis by the calcium ionophore A23187. Cholera toxin did not have an effect on the latter two assays. Pre- treatment of human neutrophils with pertussis toxin did not affect the binding of GM-CSF to its surface receptor. These results provide the first evidence that a pertussis toxin substrate plays an important mediatory role in the mechanism of action of GM-CSF. 相似文献
75.
Activation of eNOS in rat portal hypertensive gastric mucosa is mediated by TNF-alpha via the PI 3-kinase-Akt signaling pathway 总被引:4,自引:0,他引:4
Kawanaka H Jones MK Szabo IL Baatar D Pai R Tsugawa K Sugimachi K Sarfeh IJ Tarnawski AS 《Hepatology (Baltimore, Md.)》2002,35(2):393-402
Activation of endothelial nitric oxide synthase (eNOS) in portal hypertensive (PHT) gastric mucosa leads to hyperdynamic circulation and increased susceptibility to injury. However, the signaling mechanisms for eNOS activation in PHT gastric mucosa and the role of TNF-alpha in this signaling remain unknown. In PHT gastric mucosa we studied (1) eNOS phosphorylation (at serine 1177) required for its activation; (2) association of the phosphatidylinositol 3-kinase (PI 3-kinase), and its downstream effector Akt, with eNOS; and, (3) whether TNF-alpha neutralization affects eNOS phosphorylation and PI 3-kinase-Akt activation. To determine human relevance, we used human microvascular endothelial cells to examine directly whether TNF-alpha stimulates eNOS phosphorylation via PI 3-kinase. PHT gastric mucosa has significantly increased (1) eNOS phosphorylation at serine 1177 by 90% (P <.01); (2) membrane translocation (P <.05) and phosphorylation (P <.05) of p85 (regulatory subunit of PI 3-kinase) by 61% and 85%, respectively; (3) phosphorylation (P <.01) and activity (P <.01) of Akt by 40% and 52%, respectively; and (4) binding of Akt to eNOS by as much as 410% (P <.001). Neutralizing anti-TNF-alpha antibody significantly reduced p85 phosphorylation, phosphorylation and activity of Akt, and eNOS phosphorylation in PHT gastric mucosa to normal levels. Furthermore, TNF-alpha stimulated eNOS phosphorylation in human microvascular endothelial cells. In conclusion, these findings show that in PHT gastric mucosa, TNF-alpha stimulates eNOS phosphorylation at serine 1177 (required for its activation) via the PI 3-kinase-Akt signal transduction pathway. 相似文献
76.
HaiAn Zheng James Truong Fred Carroll Manjunath P. Pai 《Antimicrobial agents and chemotherapy》2015,59(3):1767-1769
Pharmaceutical differences between the reference listed drug (RLD) and generic formulations of piperacillin-tazobactam may impact the reconstitution process for intravenous administration. This study evaluated the RLD against three generic formulations and measured their reconstitution times using a standardized process. The mean (standard deviation [SD]) reconstitution time for one generic formulation was 5.57 (1.49) min, which was 35% to 42% longer (P < 0.002) than that for the RLD and two other formulations. Observable microscopic differences in powder particle morphology may explain these findings. 相似文献
77.
Genetic and non‐genetic factors that increase the risk of non‐syndromic cleft lip and/or palate development
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Yu Nee Lee Francesco Frugoni Kerry Dobbs Jolan E. Walter Silvia Giliani Andrew R. Gennery Waleed Al-Herz Elie Haddad Francoise LeDeist Jack H. Bleesing Lauren A. Henderson Sung-Yun Pai Robert P. Nelson Dalia H. El-Ghoneimy Reem A. El-Feky Shereen M. Reda Elham Hossny Pere Soler-Palacin Ramsay L. Fuleihan Niraj C. Patel Michel J. Massaad Raif S. Geha Jennifer M. Puck Paolo Palma Caterina Cancrini Karin Chen Mauno Vihinen Frederick W. Alt Luigi D. Notarangelo 《The Journal of allergy and clinical immunology》2014