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61.
ZHU Zhi-cheng SUN Mei ZHANG Xing-yi LIU Ke-xiang SHI Dong-lei LI Jin-dong SU Ji-quan XU Yue-chi FU Xue-qi 《高等学校化学研究》2007,23(3):289-296
This study objective was to express and characterize the catalytic domain of the human T cell protein tyrosine phosphatase(△TC-PTP) and to study immunohistochemically the expression of △TC-PTP in human non-small cell lung cancers. △TC-PTP gene was PCR amplified with the cDNA of human TC-PTP as template, and cloned into the pT7 expression vector. The recombinant pT7-△TC-PTP was expressed in E. coli Rosetta ( DE3 ) host cells and puri- fied. The enzymatic characteristics of △TC-PTP including enzyme activity and kinetics assay were measured. The antiserum was prepared by immunizing rabbit with the purified recombinant △TC-PTP. Rabbit polyclonal antibody against △TC-PTP was purified by PVDF immobilized antigen affinity chromatography. Immunohistochemical staining of lung cancer tissues was performed with antibody against △TC-PTP protein. △TC-PTP gene was correctly cloned, expressed, and purified. The recombinant △TC-PTP had a highly catalytic activity of PTPase. Squamous cell lung carcinoma showed a significantly higher expression rate of △TC-PTP (76. 92%, 10/13 ) than adenocarcinoma (57.14%, 4/7) and normal lung tissue(20%, 1/5 ). This study represents the first demonstration that △TC-PTP is highly expressed in human squamous cell lung carcinomas. In addition, this study provides an important basis for further studying the biological function of TC-PTP and its relationship with lung carcinomas and other diseases. 相似文献
62.
A polystyrene-bonded stannic chloride catalyst was synthesized by the method of lithium polystyryl combined with stannic chloride. This catalyst is a polymeric organometallic compound containing 0.25 mmol Sn (Ⅳ)/g catalyst. The catalyst showed sufficient stability and catalytic activity in organic reaction such as esterification, acetalation and ketal formation, and it could be reused many times without losing its catalytic activity. 相似文献
63.
Syed A. Ali Mohammed A. Siddiqui and Mohammed A. Ali 《Reaction Kinetics and Catalysis Letters》2005,87(1):199-206
Summary A parametric study of catalytic reforming process in a pilot plant was carried out by varying the pressure, H2/HC ratio, and space velocity. The results show that lower aromatics and higher hydrogen yields can be accomplished by increasing
the space velocity in existing reformers, which will also result in better C5+yield. 相似文献
64.
Catalytic oxidation of alcohols with polymer-supported ruthenium complex under mild conditions 总被引:1,自引:0,他引:1
Qiao-xiang Kang Ju-jie Luo Yan-bin Bai Zhi-wang Yang Zi-qiang Lei 《Journal of organometallic chemistry》2005,690(26):6309-6313
Polymer-supported ruthenium-containing complex PS–Phen–Ru was synthesized (where PS = chloromethyl polystyrene resin, Phen = 1,10-phenanthroline) and was characterized by FT-IR, ICP, and XPS. The supported complex was used to catalyze the oxidation of primary aliphatic alcohols as well as aromatic alcohols in the presence of iodosylbenzene. The oxidations were carried out in acetonitrile solution, affording the corresponding aldehydes or ketones in high substrate conversion and high selectivities under mild reaction conditions. The catalyst can be easily prepared and can be recycled. 相似文献
65.
We report herein an efficient catalytic epoxidation reaction for the synthesis of epoxyketone (tert-butyl ((S)-4-methyl-1-((R)-2-methyloxiran-2-yl)-1-oxopentan-2-yl)carbamate), which is an important synthetic intermediate of carfilzomib. 相似文献
66.
溴酸钾氧化靛红催化光度法测定痕量亚硝酸根 总被引:11,自引:3,他引:11
基于磷酸介质中NO2^-催化溴酸钾氧化靛红的褪色反应,建立了测定痕量NO2^-的新方法,并讨论了其动力学条件。方法检测限为1.36×10^-6g/L,线性范围0.3 ̄2μg/25mL,方法简便,已用于环境水样中痕量NO2^-的测定。 相似文献
67.
催化极谱法连续测定岩石中钨和钼 总被引:2,自引:0,他引:2
本文提出了在二苯基乙醇酸-二苯胍-氯酸钠催化极谱体系测钨后,加入少许钛铁试剂,使钼产生一个极灵敏的导数波。谊波形尖锐、对称,便于测量钼。建立的连测体系简便灵敏,用于岩石样品中钨和钼的测定,取得了满意的效果。 相似文献
68.
催化动力学光度法测定痕量锆 总被引:4,自引:0,他引:4
研究了在弱酸性介质中,锆(Ⅳ)催化过氧化氢氧化铬蓝黑R这一新的指示反应及其动力学条件,建立了一种高灵敏、高选择性测定痕量锆的新方法,方法检出限为3.74×10-11g/mL,线性范围0~1.1μg/25mLZr(Ⅳ).用于合金钢中痕量锆的测定,结果满意. 相似文献
69.
Julia E. Barker 《Tetrahedron letters》2005,46(40):6805-6808
Mononuclear (Me3TACN)MnX3 compounds, where X is Cl−, Br−, or N3−, and Me3TACN is 1,4,7-N,N′,N″-trimethyl-1,4,7-triazacyclononane, have been tested for catalyzing both sulfide oxygenation and styrene epoxidation by tert-butyl hydroperoxide (TBHP) and display turnover frequencies (TOF) up to 200 h−1 at room temperature. Sulfoxides or sulfones may be produced selectively by varying reaction conditions. Product distribution from the oxygenation reactions of ethyl phenyl sulfide, 2-chloroethyl phenyl sulfide, and styrene is consistent with a mechanism involving an early single-electron transfer (SET) step. 相似文献
70.
氧化藏红T褪色催化荧光法测定痕量钒 总被引:13,自引:3,他引:13
研究了在酸性介质中柠檬酸存在下,痕量钒(V)催化溴酸钾氧化藏红T的褪色反应及其动力学条件,建立了催化荧光测定痕量钒的新方法。催化反应在沸水浴中进行8min,为假零级反应,反应的表观活化能力为99.21kJ/mol,反应速度常数为0.12/s;该方法的检出限为2.2×10^-8g/L;线性范围为0.2 ̄2.4μg/L研究了共存离子的影响,用于人发和煤灰中痕量钒的测定,结果令人满意。 相似文献