Publications by authors named "He-Ping Yan"

Two sample pretreatment methods of pesticide residues in Panax notoginseng of Chinese traditional medicine were developed. For Method I, the residues were extracted from homogenized tissue with n-hexane-dichloromethane (6:4) by means of ultrasonication, the crude extract was purified by an Envi-carb/NH2 solid-phase extraction (SPE) column. For Method II, matrix solid-phase dispersion (MSPD) technique was used for extracting and cleaning up.

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In the present paper, the authors prepared all the samples by the same method, and optimized the work conditions for flame qtomic absorption spectrometry. FAAS was applied to determine the trace elements, such as Pb, Cr, Cd, Cu, Zn, Hg, Se etc, in Elsholtzia bodineri Vaniot. from Mengzi, Shiping, Mile and Jianshui located in Honghe state.

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This study describes the use of cyclic peptides for use in the selection of single-chain (ScFv) antibodies specific for the HIV-1 coreceptor CCR5, a representative G-protein-coupled receptor (GPCR). A tandem ligation strategy was developed for preparing biotinylated cyclic peptides, first through an orthogonal end-to-end ligation and then a chemoselective ligation with functionalized biotin. Cyclic peptides mimicking the extracellular loops of CCR5 and their unconstrained counterparts were then used for solution-phase selection of ScFv antibodies from a phage display antibody library.

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