Twelve 23-esterified silybin derivatives with different patterns of substituents such as aromatic and aliphatic groups （1-12） were designed and synthesized. The antioxidative properties of these compounds were evalu...Twelve 23-esterified silybin derivatives with different patterns of substituents such as aromatic and aliphatic groups （1-12） were designed and synthesized. The antioxidative properties of these compounds were evaluated. The modifed silybin analogues exhibited improved inhibitory effects against rat liver homogenate lipid peroxidation compared to silybin, with exception of the trimethoxylated ester （5） and the aliphatic one （9）. Compounds 3, 5, 7, 8 and 11 displayed their protective properties on DNA cleavage in a dose-dependent manner. 2009 Xiao Kun Li. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.展开更多
The salt-gradient operation mode used in ion-exchange simulated moving bed chromatography (SMBC) can improve the efficiency of protein separations. A detailed model that takes into account any kind of adsorption/ion-e...The salt-gradient operation mode used in ion-exchange simulated moving bed chromatography (SMBC) can improve the efficiency of protein separations. A detailed model that takes into account any kind of adsorption/ion-exchange equilibrium, salt gradient, size exclusion, mass transfer resistance, and port periodic switching mechanism, was developed to simulate the complex dynamics. The model predictions were verified by the experimental data on upward and downward gradients for protein separations reported in the literature. All design and operating parameters (number, configuration, length and diameter of columns, particle size, switching period, flow rates of feed, raffinate, desorbent and extract, protein concentrations in feed, different salt concentrations in desorbent and feed) can be chosen correctly by numerical simulation. This model can facilitate the design, operation, optimization, control and scale-up of salt-gradient ion-exchange SMBC for protein separations.展开更多
DTPA 和它的二衍生物被综合并且在 DNA 劈开用作催化剂。在生理的条件下面，一系列实验被做了。有三 ligands 的 DNA 劈开的效果在不同集中，劈开时间，和 pH 价值下面被学习。结果强烈建议原生质标志 DNA (pUC 19 ) 能被 CITC-DTPA 高...DTPA 和它的二衍生物被综合并且在 DNA 劈开用作催化剂。在生理的条件下面，一系列实验被做了。有三 ligands 的 DNA 劈开的效果在不同集中，劈开时间，和 pH 价值下面被学习。结果强烈建议原生质标志 DNA (pUC 19 ) 能被 CITC-DTPA 高效地劈开。为 CITC-DTPA 催化的劈开反应，形成我 DNA 能变换主要形成 II，并且 DNA 劈开机制包含一条氧化小径。展开更多
基金supported by 985 foundation from Zhejiang University and intramural foundation from Wenzhou Medical College
文摘Twelve 23-esterified silybin derivatives with different patterns of substituents such as aromatic and aliphatic groups （1-12） were designed and synthesized. The antioxidative properties of these compounds were evaluated. The modifed silybin analogues exhibited improved inhibitory effects against rat liver homogenate lipid peroxidation compared to silybin, with exception of the trimethoxylated ester （5） and the aliphatic one （9）. Compounds 3, 5, 7, 8 and 11 displayed their protective properties on DNA cleavage in a dose-dependent manner. 2009 Xiao Kun Li. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
文摘The salt-gradient operation mode used in ion-exchange simulated moving bed chromatography (SMBC) can improve the efficiency of protein separations. A detailed model that takes into account any kind of adsorption/ion-exchange equilibrium, salt gradient, size exclusion, mass transfer resistance, and port periodic switching mechanism, was developed to simulate the complex dynamics. The model predictions were verified by the experimental data on upward and downward gradients for protein separations reported in the literature. All design and operating parameters (number, configuration, length and diameter of columns, particle size, switching period, flow rates of feed, raffinate, desorbent and extract, protein concentrations in feed, different salt concentrations in desorbent and feed) can be chosen correctly by numerical simulation. This model can facilitate the design, operation, optimization, control and scale-up of salt-gradient ion-exchange SMBC for protein separations.
基金supported by the National Natural Science Foundation of China(No.20301011)
文摘DTPA 和它的二衍生物被综合并且在 DNA 劈开用作催化剂。在生理的条件下面，一系列实验被做了。有三 ligands 的 DNA 劈开的效果在不同集中，劈开时间，和 pH 价值下面被学习。结果强烈建议原生质标志 DNA (pUC 19 ) 能被 CITC-DTPA 高效地劈开。为 CITC-DTPA 催化的劈开反应，形成我 DNA 能变换主要形成 II，并且 DNA 劈开机制包含一条氧化小径。
基金supported by the National Natural Science Foundation of China(Nos.20771039,20871122, 20971046)National Key Foundation Research Development Project(973)Item of China(No.2007CB815306)
文摘水的 DNA 像核酸酶的活动可溶的锰 corrole 5， 10， 15-tris (N-methyl-4-pyridyl )- corrolatomanganese (III )(MnIIITMPyC ) 被调查了。MnIIITMPyC 可以经由由吸收系列，粘性大小和 CD 系列显示了的外面的沟绑定模式强烈绑在 DNA。MnIIITMPyC 面对 hydroperoxide 在 DNA 氧化劈开展出了优秀催化活动。
基金Project supported by the National Natural Science Foundation of China （Nos. 20403002, 20773008）, the Beijing Novel Program （No. 2008B 12） and the National High-Tech R＆D Program （No. 2007AA05Z146）.
