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Mechano-chemical selections of two competitive unfolding pathways of a single DNA i-motif

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Chinese Physics B 2014年第6期23卷 621-628页

作者：徐悦陈虎璩玉杰 Artem K.Efremov 黎明欧阳钟灿刘冬生严洁 State key laboratory of Theoretical Physics Institute of Theoretical Physics Mechanobiology Institute National University of Singapore Department of Physics National University of Singapore School of Physics University of Chinese Academy of Sciences Department of Physics Xiamen University key laboratory of Organic Optoelectronics & Molecular Engineering of the {2. of education Department of Chemistry Tsinghua University

The DNA i-motif is a quadruplex structure formed in tandem cytosine-rich sequences in slightly acidic conditions. Besides being considered as a building block of DNA nano-devices, it may also play potential roles in regulating chromo- some stability and gene transcriptions. The stability of i-motif is crucial for these functions. In this work, we investigated the mechanical stability of a single i-motif formed in the human telomeric sequence 51-（CCCTAA）3CCC, which revealed a novel pH and loading rate-dependent bimodal unfolding force distribution. Although the cause of the bimodal unfolding force species is not clear, we proposed a phenomenological model involving a direct unfolding favored at lower loading rate or higher pH value, which is subject to competition with another unfolding pathway through a mechanically stable inter- mediate state whose nature is yet to be determined. Overall, the unique mechano-chemical responses of i-motif-provide a new perspective to its stability, which may be useful to guide designing new i-motif-based DNA mechanical nano-devices.

关键词： single-molecule techniques i-motif folding/structure of biomolecules mechanical proper-ties/biomolecules

厦门西港及其邻近海域沉积物中PAHs污染特征及生物修复研究建议

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台湾海峡 2003年第2期22卷 192-200页

作者：田蕴郑天凌王新红骆苑蓉张勇厦门大学生命科学学院应用与环境微生物研究所福建厦门361005 厦门大学国家教育部海洋环境科学重点实验室福建厦门361005

据 2.0 0 1年 7、1 0月 2.航次对厦门西港水产养殖海区沉积物中 1 6种优先监测的多环芳烃含量及 3种多环芳烃降解菌的数量进行研究 ,并与厦门西港及其邻近海域非养殖区的进行了比较 .结果表明 :其养殖区沉积物中能检测出的多环芳烃以 4... 详细信息

据 2.0 0 1年 7、1 0月 2.航次对厦门西港水产养殖海区沉积物中 1 6种优先监测的多环芳烃含量及 3种多环芳烃降解菌的数量进行研究 ,并与厦门西港及其邻近海域非养殖区的进行了比较 .结果表明 :其养殖区沉积物中能检测出的多环芳烃以 4～ 6环的为主 ,并且含量明显高于非养殖区 .在养殖海区的沉积物中检测出的苯并 (b)荧蒽、吲哚芘和苯并 (ghi) 艹北等没有最低安全值的高分子量多环芳烃将直接威胁养殖水质和生物的安全 .3种多环芳烃 (菲、荧蒽、芘 )降解菌数量的最低值都出现在养殖海区 ,而这 3种多环芳烃含量的最高值也均出现在养殖海区 .在非养殖区的 3个站位的沉积物中 ,这 3种多环芳烃的含量与其降解菌数量之间存在着一定的相关性 .作者针对沿岸海域水产养殖区多环芳烃污染的现状与特点。

关键词：海洋化学有机污染物调查分布生物降解海洋沉积物福建生物修复多环芳烃

A NEW WELL TEST MODEL FOR STRESS-SENSITIVE AND RADIALLY HETEROGENEOUS DUAL-POROSITY RESERVOIRS WITH NON-UNIFORM THICKNESSES

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Journal of Hydrodynamics 2011年第6期23卷 759-766页

作者： ZHANG Lie-hui, GUO Jing-jing, LIU Qi-guo State key laboratory of Reservoir Geology and Exploitation, Southwest Petroleum {2., Chengdu 610500, china State key laboratory of Reservoir Geology and Exploitation Southwest Petroleum University Chengdu 610500 China

This article presents a new well test model for stress-sensitive composite dual-porosity reservoirs based on the concept of permeability modulus, where the rock and fluid properties as well as the formation thickness vary in the radial direction. An analytical solution in the Laplace space for the pressure-transient behavior for a line-source, constant-rate well of this type of reservoir is obtained with the Laplace transformation and the perturbation technique. The pressure and its derivative in the reservoir and the effects of relevant parameters on the pressure-transient response are obtained. The model as well as the corresponding type curves may be used in predicting the production performance or analyzing the production data for this type of reservoir.

关键词： non-uniform thickness stress-sensitive composite dual-porosity well test model type curve

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白菜细胞核雄性不育花药的细胞化学观察

实验生物学报 2004年第4期37卷 295-302页

作者：谢潮添杨延红朱学艺田惠桥细胞生物学与肿瘤细胞工程教育部重点实验室厦门大学生命科学学院厦门361005

对一种由一对隐性基因控制的白菜细胞核雄性不育和可育株的花药进行了细胞学和组织化学研究。种子播种后,有1/4植株为不育株,其余的为可育株。通过对不育株和可育株花药发育的细胞学观察,确认不育花粉的败育发生在小孢子发育时期。用组... 详细信息

对一种由一对隐性基因控制的白菜细胞核雄性不育和可育株的花药进行了细胞学和组织化学研究。种子播种后,有1/4植株为不育株,其余的为可育株。通过对不育株和可育株花药发育的细胞学观察,确认不育花粉的败育发生在小孢子发育时期。用组织化学的方法研究了可育株和不育株花药发育过程中的多糖和脂类的分布动态,发现在减数分裂前,可育花药和不育花药的药隔细胞中都储藏了大量的淀粉粒。二者的差异仅是不育花药的绒毡层细胞液泡化明显。在减数分裂后的小孢子发育时期,可育花药的绒毡层细胞具有将药隔细胞中的淀粉粒多糖吸收并转化成脂类的功能,小孢子及以后的二胞花粉中也积累了大量的脂类储藏物质在不育花药中,虽然减数分裂后药隔细胞中的淀粉粒也都消失,但绒毡层细胞中的脂类物质相比很少,同时绒毡层细胞显示了明显的多糖反应,表明不育花药的绒毡层细胞将糖类转化为脂类的功能受阻。在小孢子的表面有些脂类物质,但在细胞质中却没有脂类积累。这一结果暗示在该种白菜细胞核雄性不育株中,由于花药绒毡层细胞转换多糖为脂类的功能失常,导致了小孢子的败育。

关键词：白菜核雄性不育小孢子发生细胞化学高等植物

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水生细菌数量与菌体大小测定技术的进展

台湾海峡 2004年第3期23卷 376-385页

作者：邱大俊焦念志钱鲁闽厦门大学海洋环境科学教育部重点实验室环境科学研究中心福建厦门361005 国家海洋局第三海洋研究所福建厦门361005

水生细菌的数量与菌体大小是海洋微生物研究的关键参数.随着技术的进步,测定这些参数的方法有了很大的发展.本文介绍了其测定技术的发展历程,并对已有的测定方法进行了介绍、归纳和评述,认为流式细胞仪测定法是测定细菌数量与菌体大小... 详细信息

水生细菌的数量与菌体大小是海洋微生物研究的关键参数.随着技术的进步,测定这些参数的方法有了很大的发展.本文介绍了其测定技术的发展历程,并对已有的测定方法进行了介绍、归纳和评述,认为流式细胞仪测定法是测定细菌数量与菌体大小较为合适的方法.

关键词：水生细菌测定技术细茵计数细胞大小海洋微生物

Extending the chains of peptides and proteins in aqueous solution by inducement of N-phosphoryl amino acids

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Extending the chains of peptides and proteins in aqueous sol...

第七届全国磷化学化工暨第四届海峡化学生物学、生物技术与医药发展讨论会

作者： Yan Liu Jia Ning Wang Yu-Fen Zhao (The key laboratory for Chemical Biology of Fujian Province Department of Chemistry{2. xiamen 361005 P. R. china The key laboratory for Cell Proliferation and Regultion Biology of ministry of education College of Lofe science Beijing Normal university Beijing 100875 P. R. china The key laboratory for Chemical Biology of Henan Province Department of Chemistry Zhengzhou university Zhengzhou 450052.P. R. china)

As well known, the origin of life on the earth is one of the most difficult scientific puzzles. In this paper, it was discovered that N-phosphoryl amino acids play an important role in the formation of peptides and proteins in aqueous solution under mild conditions. Due to inducement of N-phosphoryl amino acids, some different length peptides or proteins, such as Alanyl-Glutamine dipeptide , Growth Hormone Releasing Factor (GHRF), Bovine Insulin and Cytochrome c, were added one amino acid residue on N-terminal in aqueous solution (50mM Tris-HCl, 10mM Ca2.) after 2. or 144h incubation at 37□. And, the added amino acid residue came from the N-phosphoryl amino acid, which was proved through LC-ESI-MS/MS and MALDI-TOF-MS. In the process, a pentacoordinated phosphorous intramolecular mixed anhydride may be the activating intermediate. The experiment results indicated further that N-phosphoryl amino acid is the core of peptide-bond formation, which not only could induce amino acid to self-assemble, but also induce the longer peptides or proteins to extend. This study also suggested that N-phosphoryl amino acids or its analogs could be taken for a molecule pathway in origin of proteins or other biomacromolecules in the early earth.

关键词： Extending the chains of peptides and proteins in aqueous solution by inducement of N-phosphoryl amino acids origin

pH-Dependent Self-Assembly of Two Coordination Polymers from 2.2.bipyridine-4,4-dicarboxylic Acid

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pH-Dependent Self-Assembly of Two Coordination Polymers from...

11th Conference on Solid State Chemistry and Inorganic Synthesis Joint with 2.h Dalton Transactions International Symposium

作者： Yun-Yun Zheng,Xiang-Jian Kong,~*La-Sheng Long,~* Rong-Bin Huang,Lan-Sun Zheng State key laboratory of Physical Chemistry of solid Surface, key laboratory of analytical sciences,ministry of education and Department of Chemistry,xiamenuniversity,xiamen 361005,{12..

The design and assembly of metal-involved supramolecular architectures based on crystal engineering are currently of great interest in the field of supramelocular chemistry and material science because they can provid... 详细信息

关键词： pH-Dependent Self-Assembly of Two Coordination Polymers from 2.2.bipyridine-4,4-dicarboxylic Acid

Akt phosphorylates the TR3 orphan receptor and blocks its targeting to the mitochondria

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Akt phosphorylates the TR3 orphan receptor and blocks its ta...

2.08年中国病理生理学会第十一届肿瘤和第十二届免疫专业委员会学术会议

作者： Hang-Zi Chen Bi-Xing Zhao Wen-Xiu Zhao Li Li Bing Zhang Qiao Wu key laboratory of the {2. of education for Cell Biology and Tumor Cell Engineering,School of Life sciences,xiamen university,xiamen 361005,Fujian Province,china

Akt phosphorylates and regulates the function of many cellular proteins involved in processes such as metabolism,apoptosis,and ***,the precise mechanisms by which Akt promotes cell survival and inhibits apoptosis have been characterized in part ***3,an orphan receptor,functions as a transcription factor that can both positively or negatively regulate gene *** have previously reported that the translocation of TR3 from the nucleus to the mitochondria can elicit a proapoptotic effect in gastric cancer *** our present study,we demonstrate that Akt phosphorylates cytoplasmic TR3 through its physical interaction with the N-terminus of *** co-expressed with Akt,TR3 mitochondrial targeting was blocked and this protein adopted a diffuse expression pattern in the ***,Akt displayed an ability to disrupt the interaction of TR3 with Bcl-2.which is thought to be a critical requirement for mitochondrial TR3 to elicit ***,insulin was also found to induce the phosphorylation of TR3 and abolish TPA-induced mitochondrial localization,which was dependent upon the activation of the PI3K-Akt signaling *** together,our current data demonstrate a unique role for Akt in inhibiting TR3 functions that are not related to transcriptional activity but that correlate with the regulation of its mitochondrial *** may represent a novel signal pathway by which Akt exerts its anti-apoptotic effects in gastric cancer cells,*** regulating the phosphorylation and redistribution of orphan receptors.

关键词： Akt orphan receptor TR3 nucleocytoplasmic translocation apoptosis mitochondria targeting

A FAST WAY TO SYNTHESIS NUCLEOSIDE H-PHOSPHONATE DERIVATIVES

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A FAST WAY TO SYNTHESIS NUCLEOSIDE H-PHOSPHONATE DERIVATIVES

第17届国际磷化学大会

作者： Jian-Bin Wu1 Jian-Nan Guo1 Jun Zhang3 Shu-Na Luo1 Xiang Gao1 Yu-Fen Zhao*1 2.1Department of Chemistry School of Chemistry & Chemical Engineering xiamen university xiamen P.R.china 361005 2.he key laboratory of Bio-organic Phosphorus Chemistry ministry of education Department of Chemistry School of Life science & Engineering Tsinghua university Beijing P.R.china 100084 3Department of Biology School of Life science xiamen university xiamen P.R.china 361005

＜正＞The O-alkyl-5A-H-phosphonates of d4T or AZT have been proved to cause less nucleoside-resistant mutants of HIV, lower cytotoxicity, and higher anti-HIV activity due to easier

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