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641.
Zhao Peng CHEN Jian Hui JIANG Xiao Bing ZHANG Guo Li SHEN Ru Qin YU 《中国化学快报》2006,17(4):489-492
A novel electrochemical immunosensor with amplification effect based on the enzyme inhibition of silver deposition was proposed. In this method, the capture antibody was first immobilized onto a gold electrode via a self-assembled layer. After a sandwich immunoreaction, HRP labeled antibody was bound to the gold electrode. The HRP on the electrode inhibited silver deposition when the electrode was incubated in hydroquinone-H2O2 solution and silver ion solution. The linear sweep voltammetry was chosen to detect the deposited silver and the result showed that the peak current was linearly proportional to the content of IgG in the range of 50 to 2500 ng/mL with a detection limit of 35 ng/mL. 相似文献
642.
在B3LYP/6-31G(d)水平下研究了HIV-1 PR催化水解反应关键性的一步,即第3步反应.模型体系包括了活化位点的3个残基,Asp25(25′)-Thr26(26′)-Gly27(27′) 主要参加反应的基团,构建了由69个原子组成的较大模型体系.进一步研究表明Thr26(26′)和Gly27(27′)在水解反应中只起到保持活化位点平面构型的作用,并未直接参与水解反应.另外,详细分析了第3步反应的分子内及分子间氢键. 相似文献
643.
Marine organisms are the important source of the bioactive metabolites. A novel enolic sulfated sterol, arenicolsterol A, has been isolated from a marine annelid Arenicola cristata collected in the coast of Mainland of China.The structure was elucidated using all sorts of spectroscopic data including ESIMS, 1D and 2D NMR etc. The cytotoxic bioactivity of this sterol was evaluated by MTT assay. It could inhibit the growth of human cervix cancer cell line (Hela) and human non-small cell lung cancer cell line (NCI-h6) with IC50 of (3.1 0.6)μg/mL and (7.6 0.8)μg/mL. 相似文献
644.
LIU Jun-song. YANG Jin-gang HONG Yuan JIN Feng-hai WANG Ming-cui ZHAO Shu-hua FANG Xue-xun . Key Laboratory of Molecular Enzymology Enzyme Engineering of Ministry of Education Jilin University Changchun P. R. China . College of Life Science Changchun . College of Medicine 《高等学校化学研究》2009,25(2)
Matrix metalloproteinases(MMPs) play an essential role in development and tissue remodeling of living organisms.However,the overexpression of MMPs has lead to a series of diseases,such as cancer,arthritis,and atherosclerosis;and inhibition of MMPs may have therapeutic benefits.The discovery of MMP inhibitors from herbal has become a prospective event.We showed that the extract of Polygoni multiflori caulis from ethy1 acetate or water(ethy1 acetate extract and water extract) can inhibit the activities of MMPs 9,14,and 16 in a dose-dependent manner and n-buty1 alcohol extract of it can also inhibit these MMPs.Furthermore,we found that n-buty1 alcohol extract and water extract of it influence the cell viability.These discoveries may contribute to the development of MMP inhibitors for the therapy of a variety of pathological conditions. 相似文献
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646.
人工蜂王的研制及对东方蜜蜂的生物活性 总被引:3,自引:0,他引:3
本文模拟天然蜂王信息素的组成,将合成的9-氧代-2E-癸烯酸(蜂王物质,QueenSubstance)、R/S-9-羟基-2E-癸烯酸(臭味抑制剂,Stink-odourinhibitor)及其它一些微量成分按一定的比例混合,并附于醋酸纤维上制成人工蜂王,运用人工蜂王对东方蜜蜂进行了活性测试,结果表明在群味、聚集、消除失王情绪、抑制工蜂产卵、抑制建造急造王台等方面表现出了显著的生物活性,同时也研究了人工蜂王对产蜜量的影响。 相似文献
647.
Xing Zhou Li ;Xian Ping Dai ;Kang Ying Lai ;Li Li Wang ;Zhi Bing Zheng ;Song Li 《中国化学快报》2008,19(4):379-382
A series of 2,4,5-triaryl substituted 1H-pyrazol-3(2H)-ones,as ALK5 inhibitors,were desigened,synthesized and evaluated in vitro.Most compounds exhibited noticeable ALK5 inhibition activities at 1μmol/L and displayed no significant cytotoxicities at 30μmol/L. 相似文献
648.
649.
ZHAO Hai-feng YU Ting LIU Xin LIU Rui ZHENG Lan SONG Li-na JIA Li YANG Hong HE Cheng-yan 《高等学校化学研究》2009,(4):497-499
Deletion of the codon encoding the phenylalanine residue at position 508(ΔF508) in the cystic fibrosis transmembrane conductance regulator(CFTR) is the most common mutation causing cystic fibrosis(CF).The human ΔF508 mutation results in a CFTR protein with impaired folding,trafficking,and gating in human and rodents.Recent studies suggest that pig ΔF508-CFTR can be efficiently processed to the plasma membrane as maturely glycosylated protein,indicating species difference of the molecular mechanisms of CFTR ... 相似文献
650.