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151.
Chunfu Zhang Yongxian Wang Haibin Tian Duanzhi Yin 《Journal of Radioanalytical and Nuclear Chemistry》2002,253(2):313-316
A method for 103Pd molecular plating onto the surface of the copper rod is reported. The optimal composition of the plating bath was: palladium chloride 2 g/l, ammonium hydroxide (28%) 150 ml/l, sodium hypophosphite 12 g/l, and ammonium chloride 37 g/l. The whole procedure of 103Pd molecular plating will last 50 minutes at 40 °C. This article provides valuable experience for the preparation of 103Pd seeds. 相似文献
152.
CBr_4和CCl_4分子的解离反应前人已做了许多工作,他们分别采用射频放电、电子轰击、He~ 的传能反应等方法研究了CCl_4和CBr_4的解离反应,得到了CCI(A)、CCl~ 、CBr~ 等碎片的发射光谱。有关亚稳态原子与它们的传能反应,只有某些较简单的报道,对传能反应机理也未作深入探讨。本文研究了各种亚稳态原子He(2~3S)、Ne(~3P_(0.2))、Ar(~3P_(0.2))与CCl_4和CBr_4分子的传能反应,并对反应机理进行了初步的讨论和分析。 相似文献
153.
154.
YU Zhaoxiang QI Rong & YIN Yanjun Department of Chemistry Tongji University Shanghai China 《中国科学B辑(英文版)》2005,48(5):489-496
The long-term environmental impacts of wastewa-ter from coke plant can be very high, especially due to the discharge of large amounts of wastewater. The composition of coke plant wastewater is complicated and varies from one factory to another, depending … 相似文献
155.
Qing-shan Liang Jian-Gang Xie ChaoPing Yu ZhuSheng Feng JingChang Ma Yuan Zhang Dong Wang JianGuo Lu Ran Zhuang Jikai Yin 《Experimental & molecular medicine》2021,53(3):393
Splenectomy has been reported to improve liver fibrosis in patients with cirrhosis and hypersplenism. However, the mechanisms remain unclear. Tumor necrosis factor superfamily 14 (TNFSF14; also known as LIGHT) is highly expressed in the context of fibrosis and promotes disease progression in patients with fibrotic diseases such as pulmonary and skin fibrosis. Here, we determined whether splenectomy controls the production of LIGHT to improve liver fibrosis. Splenectomy reduced serum LIGHT levels in cirrhotic patients with hypersplenism and a ConA-induced liver fibrosis mouse model. Blocking LIGHT resulted in the downregulation of TGF-β1 in RAW264.7 cells. LIGHT treatment of RAW264.7 and JS1 cells in coculture regulated transforming growth factor-β1 (TGF-β1) expression through the activation of JNK signaling. Small interfering RNA-mediated silencing of lymphotoxin β receptor (LTβR) in macrophages resulted in pronounced decreases in the levels of fibrosis and αSMA in JS1 cells. These results indicated that LIGHT bound to LTβR and drove liver fibrosis in vitro. Blocking TGF-β1 abolished the effect of LIGHT in vitro. Furthermore, the administration of recombinant murine LIGHT protein-induced liver fibrosis with splenectomy, while blocking LIGHT without splenectomy improved liver fibrosis in vivo, revealing that the decrease in fibrosis following splenectomy was directly related to reduced levels of LIGHT. Thus, high levels of LIGHT derived from the spleen and hepatic macrophages activate JNK signaling and lead to increased TGF-β1 production in hepatic macrophages. Splenectomy attenuates liver fibrosis by decreasing the expression of LIGHT.Subject terms: Tumour-necrosis factors, Liver fibrosis, Hepatic stellate cells, Liver cirrhosis, Experimental models of disease 相似文献
156.
This review aims to provide a summary of the progress in organic small molecular fluorescent dyes for photodynamic therapy in recent years and it is classified according to the structures of dyes including cyanines, phthalocyanine, BODIPYs and other agents. 相似文献
157.
Terephthalamide derivatives as mimetics of helical peptides: disruption of the Bcl-x(L)/Bak interaction 总被引:4,自引:0,他引:4
Yin H Lee GI Sedey KA Rodriguez JM Wang HG Sebti SM Hamilton AD 《Journal of the American Chemical Society》2005,127(15):5463-5468
A series of Bcl-x(L)/Bak antagonists, based on a terephthalamide scaffold, was designed to mimic the alpha-helical region of the Bak peptide. These molecules showed favorable in vitro activities in disrupting the Bcl-x(L)/Bak BH3 domain complex (terephthalamides 9 and 26, K(i) = 0.78 +/- 0.07 and 1.85 +/- 0.32 microM, respectively). Extensive structure-affinity studies demonstrated a correlation between the ability of terephthalamide derivatives to disrupt Bcl-x(L)/Bak complex formation and the size of variable side chains on these molecules. Treatment of human HEK293 cells with the terephthalamide derivative 26 resulted in disruption of the Bcl-x(L)/Bax interaction in whole cells with an IC(50) of 35.0 microM. Computational docking simulations and NMR experiments suggested that the binding cleft for the BH3 domain of the Bak peptide on the surface of Bcl-x(L) is the target area for these synthetic inhibitors. 相似文献
158.
Changzheng Wu Qing Yang Chao Huang Ping Yin Yi Xie 《Journal of solid state chemistry》2004,177(10):3522-3528
Pure hexagonal aluminum nitride (AlN) nanowhiskers have been successfully synthesized by directly reacting AlCl3 with NaN3 in non-solvent system at the low temperature of 450 °C for 24 h. The obtained products are characterized by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, high-resolution transmission electron microscopy and selected area electron diffraction, which show that the obtained products are hexagonal phase AlN nanowhiskers with width from 10 to 80 nm and length up to several micrometers. The influencing factors of the formation of AlN nanowhiskers were discussed and a possible growth mechanism for AlN nanowhiskers was proposed. Additionally, the study on the corresponding optical properties and catalytic properties is also carried out. 相似文献
159.
The gold nanoprisms (GNPs) have exhibited special plasmonic properties for biomedical applications because of their unique shapes and dimensions. Based on their optical performance, the NIR dye IR780 not only enabled the GNPs-based nanosystem as SERRS nanoparticles for Raman-encoded molecular imaging, but also enhanced the plasmonic photothermal property by laser irradiation. Meanwhile, the GNPs/IR780-Lyp-1 by introduction of tumor-homing peptide segment LyP-1, which presents high affinity to p32 protein, demonstrated the increased enrichment in tumor region and enhanced photothermal therapy efficacy. 相似文献
160.
A method was developed for the determination of rare earth impurities in high purity Gd(2)O(3) by inductively coupled plasma mass spectrometry (ICP-MS). The matrix suppression effect of Gd(2)O(3) on signals of rare earth impurities was compensated for by Re internal standardization. The spectra overlap interferences from GdH, GdO, GdOH(n) (n=1-3) on Tb, Tm, Yb and Lu were eliminated by 2-thylhexylhydrogen-2-ethylhexy phosphonate (EHEHP) extraction chromatographic separation. The detection limits for REEs were 0.005-0.017 ng ml(-1) in solution and 0.002-0.05 mug g(-1) in solid. Recoveries of spiked sample for REEs were from 88 to 121% with the precision of 1.0-7.5% RSD. Determination of trace REEs in two Gd(2)O(3) samples were performed. The method can be applied to analysis of 99.99-99.9999% high purity Gd(2)O(3). 相似文献