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991.
Filter-based microfluidic device as a platform for immunofluorescent assay of microbial cells 总被引:5,自引:0,他引:5
A filter-based microfluidic device was combined with immunofluorescent labeling as a platform to rapidly detect microbial cells. The coin-sized device consisted of micro-chambers, micro-channels and filter weirs (gap = 1-2 microm), and was demonstrated to effectively trap and concentrate microbial cells (i.e., Cryptosporidium parvum and Giardia lamblia), which were larger in size than the weir gap. After sample injection, a staining solution containing fluorescently-labeled antibodies was continuously provided into the device (flow rate = 20 microl min(-1)) to flush the microbial cells toward the weirs and to accelerate the fluorescent labeling reaction. Using a staining solution that was 10 to 100 times more dilute than the recommended concentration used in a conventional glass method, those target cells with a fluorescent signal-to-noise ratio of 12 could be microscopically observed at single-cell level within 2 to 5 min prior to secondary washing. 相似文献
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993.
Li Qiu WANG Xiao Jun PENG* Rong ZHANG Guo Quan XU Jing Nan CUI State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 《中国化学快报》2003,(1)
Indocyanine dyes as fluorescent labeling reagents have been used in bioanalysis1,2. Arylsulfonate indocyanine dyes 1d and 1e developed by Waggoner A. S. et al.3,4 have excellent fluorescent properties combined with good aqueous solubility, are a new generation of fluorescent label compounds for proteins, oligonucleotides and other compounds containing hydroxyl, mercaptol or primary amine groups5. However, photostability of these dyes has been a problem. Z. G. YAO et al.6 reported that p… 相似文献
994.
The photochemical reaction of Re2(CO)10 with thiophene in hexane solution was investigated under vacuum. Three rhenium clusters: H2Re3(CO)12, HRe3(CO)14 and Re3(CO)14(OH)4, were isolated. The structure of Fellmann-Kaesz cluster Complex HRe3(CO)14 was determined by use of the X-ray diffraction method. The three rhenium atoms form a plane of symmetry and L: Re1Re2Re3 is 107°. The ten carbonyl groups bonded to the two terminal rhenium atoms Re1 and Re3, are staggered with respect to the central rhenium atoms. The bond lengths are 3.10 Å for Re2-Re3 and 3.34 Å for Re1-Re2. The bridging hydride is between Re1 and Re2. 相似文献
995.
本文用积分估计和不动点原理证明了一类广义Kuramoto-Sivashinsky型方程初值问题光滑整体解的存在唯一性,并在不同情况下讨论了解的破裂性,并给出了导致破裂性的充分条件. 相似文献
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M. Liang H. Ohm B. De Sutter K. Sistemich 《Zeitschrift für Physik A Hadrons and Nuclei》1992,344(3):357-358
Tie half-lives of 8 low lying levels of103Nb have been determined at the fission-product separator JOSEF. A B-- triple-coincidence method was used which consists in a measurement of the time delay between the feeding of the levels through the B– decay of103Zr and their decay, in coincidence with a tagging ray, with plastic, BaF2 and Ge detectors, respectively. Most of the investigated levels are members of the three known rotational bands based on the ground state and the 164 and 248 keV levels. The deformation Bq=0.31(3) of103Nb could be deduced from the half-life data. The half-lives are well reproduced through calculations in the frame of the Nilsson model.The authors thank Dr. T. Seo for valuable advise in connection with the Nilsson-model calculations. 相似文献
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