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Development of an LC‐MS/MS method for determining the pharmacokinetics of clonidine following oral administration of Zhenju antihypertensive compound 下载免费PDF全文
Jing Qin Limin Wang Lihong Wu Jun Chen Teng Shen Yongji Li Limei Han Jianxin Wang 《Biomedical chromatography : BMC》2015,29(7):1068-1075
Zhenju antihypertensive compound (ZJAHC) is a combined Chinese–Western medicine formula including clonidine (CLO), hydrochlorothiazide (HCT), rutin, Chrysanthemum indicum extract and pearl powder. Compared with CLO preparations, ZJAHC shows improved activities and decreased adverse effects. It is believed that the side effects of CLO are caused by its high peak plasma concentration. Hence, study of the influence of ZJAHC on the pharmacokinetic behaviors of clonidine seems essential. In present study, the plasma concentrations of CLO were determined with a liquid chromatography–tandem mass spectrometry (LC‐MS/MS) method. The MS/MS transitions monitored for clonidine and internal standard were 230.2 → 213.1 and 152.2 → 110.2, respectively. The analyte was quantified in a single run within 3 min. The pharmacokinetic study showed that the area under the plasma concentration–time curve of CLO in ZJAHC (60 µg/kg CLO) was similar to that of CLO‐HCT‐high (120 µg/kg CLO) but the peak concentration was much lower than that in CLO‐HCT‐high. ZJAHC could enhance the bioavailability without greatly increasing peak concentration of clonidine. This comprehensive effect of enhancing the bioavailability and avoiding the high peak plasma concentration for CLO might mainly result from the co‐contribution of Western medicine and traditional Chinese medicine (TCM), while the effect of TCM was stronger than that of Western medicine. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Wen‐Jing Guo Yong‐Tao Wang De‐Xian Kong Jin‐Yun Wang Prof. Qiao‐Hua Wei Guo‐Nan Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(11):4205-4208
A heterometallic cluster [Ag6Au6(ethisterone)12] of an unprecedented topology was synthesized and characterized. A sensitive and specific probe for estrogen receptor α (ERα) has been developed for the first time based on the enhancement of the Ag6Au6 luminescence. 相似文献
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Dekun Wu Dr. Qing Xu Dr. Jing Qian Prof. Xiaopeng Li Prof. Yuhan Sun 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(12):3105-3111
Covalent organic frameworks (COFs) are a new class of crystalline porous polymers comprised mainly of carbon atoms, and are versatile for the integration of heteroatoms such as B, O, and N into the skeletons. The designable structure and abundant composition render COFs useful as precursors for heteroatom-doped porous carbons for energy storage and conversion. Herein, we describe a multifunctional electrochemical catalyst obtained through pyrolysis of a bimetallic COF. The catalyst possesses hierarchical pores and abundant iron and cobalt nanoparticles embedded with standing carbon layers. By integrating these features, the catalyst exhibits excellent electrochemical catalytic activity in the oxygen reduction reaction (ORR), with a 50 mV positive half-wave potential, a higher limited diffusion current density, and a much smaller Tafel slope than a Pt-C catalyst. Moreover, the catalyst displays superior electrochemical performance toward the hydrogen evolution reaction (HER), with overpotentials of −0.26 V and −0.33 V in acidic and alkaline aqueous solution, respectively, at a current density of 10 mA cm−2. The overpotential in the catalysis of the oxygen evolution reaction (OER) was 1.59 V at the same current density. 相似文献
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We propose two new type sine hyperbolic potentials and . They may become single- or double-well potentials depending on the potential parameters and k. We find that its exact solutions can be written as the confluent Heun functions , in which the energy level E is involved inside the parameter η. The properties of the wave functions, which is strongly relevant for the potential parameters and k, are illustrated. 相似文献