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41.
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
42.
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
43.
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
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Wilson disease (WD) is a rare autosomal recessive disorder of copper metabolism which primarily involves the liver and the central nervous system. Rarely, WD can present as acute liver failure (ALF) and this disease is universally fatal in the absence of liver transplantation. The authors report a young girl with WD ALF, who showed signs of recovery after prompt initiation of plasma exchange (PE) and chelation therapy. Though liver transplantation could not be done in this child and the child died 8 d after stopping PE, this case highlights that PE can be a successful medical treatment in WD ALF and should be considered as a therapeutic measure to stabilize a patient by decreasing serum copper, reducing hemolysis, and helping to prevent renal tubular injury from copper and copper complexes until liver transplantation is possible. 相似文献
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Background The close relationship between the thyrotoxic state and abnormalities in cardiac function,arrhythmias and congestive heart failure is well known to clinicians. Patients with hyperthyroidism-induced acute myocardial infarction(AMI) are unusual and almost all reported cases have been associated with coronary vasospasm. There is quite consistent evidence that hyperthyroidism is directly associated with the presence of a prothrombotic state. Methods The present article reports a 69-year-old female with hyperthyroidism who developed myocardial infarction(MI) and reviews AMI in hyperthyroidism cases reported in the literature. We conducted a comprehensive review of the English literature since 1990 to analyze data on MI in hyperthyroidism patients who had developed AMI. Results From 11 English articles, we identified 12 hyperthyroidism patients, plus our cases, with AMI. They consisted of 11 females and 2 males.Their mean age was 49 ± 14.4 years(range 28-71). Coronary angiography revealed normal coronary arteries in 6 patients, coronary spasm in 6 patients. Only our patient received percutaneous coronary intervention through coronary thrombus suction and other patients were treated mainly with medicine. Twelve patients had good prognosis and 1 patient died of cardiogenic shock. Conclusions Hyperthyroidism-induced AMI is rare.Coronary thrombus or spasm without coronary atherosclerotic stenosis should be considered. Different therapies should be chosen according to different types of coronary involvement. 相似文献
50.
RC Iskow O Gokcumen A Abyzov J Malukiewicz Q Zhu AT Sukumar AA Pai RE Mills L Habegger DA Cusanovich MA Rubel GH Perry M Gerstein AC Stone Y Gilad C Lee 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(31):12656-12661
Gene expression differences are shaped by selective pressures and contribute to phenotypic differences between species. We identified 964 copy number differences (CNDs) of conserved sequences across three primate species and examined their potential effects on gene expression profiles. Samples with copy number different genes had significantly different expression than samples with neutral copy number. Genes encoding regulatory molecules differed in copy number and were associated with significant expression differences. Additionally, we identified 127 CNDs that were processed pseudogenes and some of which were expressed. Furthermore, there were copy number-different regulatory regions such as ultraconserved elements and long intergenic noncoding RNAs with the potential to affect expression. We postulate that CNDs of these conserved sequences fine-tune developmental pathways by altering the levels of RNA. 相似文献