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1.
Studies on metabolism of total glucosides of paeony from Paeoniae Radix Alba in rats by UPLC‐Q‐TOF‐MS/MS 下载免费PDF全文
Wenli Cao Xinguo Wang Haojie Li Xuliang Shi Wencheng Fan Shaohua Zhao Minyan Liu Liying Niu 《Biomedical chromatography : BMC》2015,29(11):1769-1779
Total glucosides of paeony are the active constituents of Paeoniae Radix Alba. In this study, a novel strategy was proposed to find more metabolites and the differences between paeoniflorin, albiflorin and total glucosides of paeony (TGP). This strategy was characterized as follows: firstly, the animals were divided into three groups (paeoniflorin, albiflorin and TGP) to identify the source of TGP metabolites from paeoniflorin or albiflorin; secondly, a generic information‐dependent acquisition scan for the low‐level metabolites was triggered by the multiple mass defect filter and dynamic background subtraction; thirdly, the metabolites were identified with a combination of data‐processing methods including mass defect filtering, neutral loss filtering and product ion filtering; finally, a comparative study was used in the metabolism of paeoniflorin, albiflorin and TGP. Based on the strategy, 18 metabolites of TGP, 10 metabolites of paeoniflorin and 13 metabolites of albiflorin were identified respectively. The results indicated that the hydrolysis, conjugation reaction and oxidization were the major metabolic pathways, and the metabolic sites were the glycosidic linkage, the ester bond and the benzene ring. This study is first to explore the metabolism of TGP, and these findings enhance our understanding of the metabolism and the interactions of paeoniflrin and albiflorin in TGP. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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In this paper, we discuss the local and global existence ofweak solutions for some hyperbolicparabolic systems modellingchemotaxis. 相似文献
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The purpose of this article is to support the idea that “whenever we can prove a limit theorem in the classical sense for a dynamical system, we can prove a suitable almost-sure version based on an empirical measure with log-average”. We follow three different approaches: martingale methods, spectral methods and induction arguments. Our results apply, among others, to Axiom A maps or flows, to systems inducing a Gibbs–Markov map, and to the stadium billiard. 相似文献
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本文提出一种利用材料Hugoniot数据研究高压下离子晶体中微观离子状态及其离子间排斥作用势的新方法。对氢化锂晶体进行研究时,我们得到Li~+和H~-离子之间排斥作用势函数,结果表明文献〔1〕中提出的离子压缩效应具有客观性。 相似文献
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Investigation on chaotic motion in hysteretic non-linear suspension system with multi-frequency excitations 总被引:3,自引:0,他引:3
This paper presents the investigation on possible chaotic motion in a vehicle suspension system with hysteretic non-linearity, which is subjected to the multi-frequency excitation from road surface. The Melnikov’s function is used to derive the critical condition for the chaotic motion, and then it is investigated that the effects of parameters in non-linear damping on the chaotic field. The path from quasi-periodic to chaotic motion is found via Poincaré map and Lyapunov exponents. 相似文献
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当离子蒸气冷凝形成团簇时,其结构表现出特定的规律。文中对不同大小不同形状的氯化钠团簇结构与结合能进行了计算,以求揭示离子蒸气冷凝形成团簇的一些规律,并与实验结果进行对照。 相似文献
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应用全倒易空间X 射线散射理论分析(FRS XRSA)与SAXS研究了HEPP在应变(ε)与回复(R)过程中结晶、取向与超结构的变化.结果指出,ε可以诱发结晶,但当ε≥30%后,结晶度(XWC)趋于不变:ε可以导致晶粒破碎;ε与R对取向分布与平均取向基本上无影响,这符合片晶平行分离模型,而非叶簧弯曲模型;发现,在ε≤30%时,层状片晶的分离为主要过程,而当ε>30%后,则分离的片晶会发生断层滑移;ε可以诱发微孔,类似地当ε>20%,微孔尺寸亦趋不变.从凝聚态结构阐明了HEPP在ε R过程中不同阶段的结构变化 相似文献