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141.
Xue-qiang Yin 《Tetrahedron》2005,61(7):1839-1843
A straightforward synthesis of (1S,2R,3R,4R)-4-(6-aminopurin-9-yl)-2-hydroxymethylcyclopentane-1,3-diol (2), an isomer of aristeromycin, and its 2′-deoxy derivative 3 from readily available disubstituted cyclopentenes is presented. An antiviral analysis of 2 showed it to have significant activity versus Epstein-Barr virus (IC50 0.62 μg/mL in the Elisa assay) and to be free of cytotoxicity effects against the host cells. In a much less comprehensive antiviral analysis, 3 also was active towards Epstein-Barr (IC50 7.58 μg/mL in the Elisa assay) but this was accompanied by cellular toxicity.  相似文献   
142.
A novel TPPTS-Rh/SiO2 catalyst, prepared by directly modifying a heterogeneous high-surface-area Rh/SiO2 catalyst with water-soluble TPPTS ligands, could decrease the resistance of masstransfer in water/oil biphasic media for the hydroformylation of higher olefins. The catalytic performancefor hydroformylation on this biphasic TPPTS-Rh/SiO2 catalyst system was higher than those of thetraditional biphasic HRhCO(TPPTS)3 systems, owing to the chemical bonds between the highly dispersedRh metal particles and the TPPTS ligands. The catalyst system is applicable for hydroformylation ofhigher olefins such as 1-dodecene.  相似文献   
143.
In the title complex, [Zn(C12H6O4)(H2O)]n, a ZnII polymer based on naphthalene‐1,8‐dicarboxylate (1,8‐nap), the ZnII atoms adopt an elongated octahedral coordination geometry. A zigzag chain is formed by μ2‐aqua ligands and μ2‐carboxylate groups of the 1,8‐nap ligands. Adjacent parallel chains are further linked by 1,8‐nap ligands, forming a twisted two‐dimensional layer structure along the (100) plane.  相似文献   
144.
A novel metal/semiconductor nanocomposite with catalytic and photocatalytic functions has been prepared. The new material consists of highly dispersed platinum (Pt) nanoparticles embedded in a cubic mesoporous nanocrystalline anatase (meso-nc-TiO2) thin film. The porous thin film possesses a narrow pore-size distribution and a large surface area. The diameter of the Pt cluster can be controlled to below 5 nm, and the high dispersion of these clusters gives rise to catalytic activity for the oxidation of carbon monoxide, an important reaction for automobile exhaust treatment. This novel ordered mesoporous Pt/TiO2 nanoarchitecture is also a promising photochemical material, as demonstrated by the photo-driven killing of Micrococcus lylae cells on the film.  相似文献   
145.
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   
146.
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   
147.
用于气/固吸附的微分吸附热测定装置   总被引:1,自引:0,他引:1  
本文介绍了一套吸附热测定装置, 它是对法国SETARAM高温量热计进行了适当变动后而建成的。用它可以测定在室温~800 K范围内气/固吸附的微分吸附热。在实验过程中, 吸附量是用光标微压计进行测量。用电标定法代替标准物质法来测定该装置的热定量因子, 这更适合于在恒温条件下的吸附热测定。用这套装置测定了吡啶在HY分子筛上于不同温度下的吸附热。  相似文献   
148.
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   
149.
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   
150.
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   
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