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131.
132.
Xiaoling Bao Jianhong Liu Qingshu Zheng Wei Pei Yimei Yang Yanyun Dai Tao Tu 《中国化学快报》1990,30(12):2266-2270
A novel protocol allowing convenient and highly selective visual recognition of melamine in raw milk via selective metallo-hydrogel formation at a concentration as low as 10 ppm without any tedious pretreatment has been developed. 相似文献
133.
Optical detection of triggered atherosclerotic plaque disruption by fluorescence emission analysis 总被引:2,自引:0,他引:2
Christov A Dai E Drangova M Liu L Abela GS Nash P McFadden G Lucas A 《Photochemistry and photobiology》2000,72(2):242-252
Fluorescence emission analysis (FEA) has proven to be very sensitive for the detection of elastin, collagen and lipids, which are recognized as the major sources of autofluorescence in vascular tissues. FEA has also been reported to detect venous thromboemboli. In this paper we have tested the hypothesis that FEA can reproducibly detect in vivo and in vitro triggered plaque disruption and thrombosis in a rabbit model. Fluorescence emission (FE) spectra, recorded in vivo, detected Russell's viper venom (RVV)-induced transformation of atherosclerotic plaque. FE intensity at 410-490 nm 4 weeks after angioplasty was significantly lower (P < 0.0033 by analysis of variance) in RVV-treated rabbits when compared to control animals with stable plaque. FE spectral profile analyses also demonstrated a significant change in curve shape as demonstrated by polynomial regression analysis (R2 from 0.980 to 0.997). We have also demonstrated an excellent correlation between changes in FE intensity and the structural characteristics detected at different stages of "unstable atherosclerotic plaque" development using multiple regression analysis (R2 = 0.989). Thus, FEA applied in vivo is a sensitive and highly informative diagnostic technique for detection of triggered atherosclerotic plaque disruption and related structural changes, associated with plaque transformation, in a rabbit model. 相似文献
134.
在 pH 4.5 HAc-NaAc缓冲溶液中,钍试剂分别于- 0.36 V、- 0.60 V产生两个灵敏的极谱波。基于钒对溴酸钾氧化钍试剂的催化作用,建立了双极谱波测量的催化动力学极谱法。钒浓度在0.7~15μg/L与△I(△I1+ I2)呈线性关系,检测限为0.5μg/L。研究了极谱波性质及电极反应机理。本法简便、灵敏、准确,已用于直接测定水中痕量钒。 相似文献
135.
Barluenga J Diéguez A Rodríguez F Flórez J Fañanás FJ 《Journal of the American Chemical Society》2002,124(31):9056-9057
Eight-membered carbocycles with up to five new stereogenic centers are enantioselectively obtained following a one-pot procedure that involves the coupling of three components: an alkenyl Fischer carbene complex, a ketone enolate, and allyl lithium. 相似文献
136.
137.
The covalent immobilization of DNA onto self-assembled monolayer (SAM) modified gold electrodes (SAM/Au) was studied by X-ray photoelectron spectrometry and electrochemical method so as to optimize its covalent immobilization on SAMs. Three types of SAMs with hydroxyl, amino, and carboxyl terminal groups, respectively, were examined. Results obtained by both X-ray photoelectron spectrometry and cyclic voltammetry show that the largest covalent immobilization amount of dsDNA could be gained on hydroxyl-terminated SAM/Au. The ratio of amount of dsDNA immobilized on hydroxyl-terminated SAMs to that on carboxyl-terminated SAMs and to that on amino-terminated SAMs is (3-3.5): (1-1.5): 1. The dsDNA immobilized covalently on hydroxyl-terminated SAMs accounts for 82.8-87.6% of its total surface amount (including small amount of dsDNA adsorbed). So the hydroxyl-terminated SAM is a good substrate for the covalent immobilization of dsDNA on gold surfaces. 相似文献
138.
SynthesisandMagnetismof2┐Hydroxy┐1,3┐propylene┐bis(oxamato)┐bridgedCoⅡCuⅡCoⅡComplexesMIAOMing-ming,CHENGPeng,LIAODai-zhengJIA... 相似文献
139.
石墨炉原子吸收法测定生物样品中镉的几种基体改进剂的比较 总被引:5,自引:0,他引:5
本文比较了磷酸二氢铵、氟化铵、硫酸铵、氯化钯、氯铂酸以及氯铂酸与多种有机酸的混合试剂在测定GBW猪肝标准物质中镉时基体改进效果,其中,氯铂酸的基体改进能力最强,猪肝标准物质的回收率在90% 相似文献
140.
P. Jing R. -N. Fu R. -J. Dai J. -L. Ge J. -L. Gu Z. Huang Y. Chen 《Chromatographia》1996,43(9-10):546-550