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华东地区前寒武纪主要地质事件及构造演化

资源调查与环境 2005年第2期26卷 79-85页

作者：包超民邢光福周宇章南京地质矿产研究所江苏南京210016

通过对地层分区与板块构造关系的分析,依据华东地区前寒武纪地质事件主要特点及划分原则,在充分了解现代构造观和基本地质事实基础上,建议将华东地区“晋宁运动二幕”改为“休宁上升”;“栏杆运动”和“霍丘运动”改为“栏杆上升”和“... 详细信息

通过对地层分区与板块构造关系的分析,依据华东地区前寒武纪地质事件主要特点及划分原则,在充分了解现代构造观和基本地质事实基础上,建议将华东地区“晋宁运动二幕”改为“休宁上升”;“栏杆运动”和“霍丘运动”改为“栏杆上升”和“霍丘上升”,因为它们不具备造山运动性质。通过对新太古代末蚌埠运动、古元古代末龙川运动、迪口运动,中元古代末凤阳运动、青白口纪内部神功运动的特点分析,认为区内经历了新太古代陆核的生成;古元古代褶皱变质和混合岩化;凤阳运动和神功运动造成了华北古板块、扬子古板块和华夏古板块的拼合等演化阶段;并发生了四次造山运动和三次裂陷运动。

关键词：造山运动裂陷运动板块拼合前寒武纪

槲皮素通过STAT通路抑制胶质瘤干细胞增殖促进其凋亡

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中国组织工程研究 2017年第5期21卷 657-662页

作者：刘义锋张保朝温昌明闻公灵周国平张敬伟贺海发汪宁李巍郑州大学附属南阳中心医院神经内科河南省南阳市473000 郑州大学附属南阳中心医院神经外科河南省南阳市473000 郑州大学附属南阳中心医院肿瘤内科河南省南阳市473000 郑州大学附属南阳中心医院病理科河南省南阳市473000 解放军沈阳军区总医院神经内科辽宁省沈阳市110016

背景:多项研究表明,槲皮素可抑制肿瘤细胞的增殖、迁移并促进其凋亡。目的:探索槲皮素对胶质瘤干细胞增殖及凋亡的影响。方法:采用免疫磁珠分离培养胶质瘤干细胞,分4组培养,分别以含0(对照),25,50,100μmol/L槲皮素的培养基培养。48 h后... 详细信息

背景:多项研究表明,槲皮素可抑制肿瘤细胞的增殖、迁移并促进其凋亡。目的:探索槲皮素对胶质瘤干细胞增殖及凋亡的影响。方法:采用免疫磁珠分离培养胶质瘤干细胞,分4组培养,分别以含0(对照),25,50,100μmol/L槲皮素的培养基培养。48 h后,MTT法检测细胞增殖,流式细胞仪检测细胞凋亡,Western blot检测增殖相关蛋白增殖细胞核抗原、凋亡相关蛋白Bcl-2、Bax和存活素及STAT3、p-STAT3的表达。结果与结论:(1)与对照组比较,槲皮素呈剂量依赖性抑制胶质瘤干细胞的增殖(P<0.05);随着槲皮素浓度的升高,胶质瘤干细胞增殖细胞核抗原表达逐渐降低;(2)与对照组比较,槲皮素呈剂量依赖性促进胶质瘤干细胞的凋亡(P<0.05);随着槲皮素浓度的升高,胶质瘤干细胞促凋亡蛋白Bax表达逐渐升高,抑制凋亡蛋白Bcl-2和存活素表达逐渐降低;(3)随着槲皮素浓度的升高,胶质瘤干细胞p-STAT3表达逐渐降低,STAT3表达无明显变化;(4)结果表明,槲皮素可能通过抑制STAT通路抑制胶质瘤干细胞的增殖,促进其凋亡。

关键词：中草药肿瘤干细胞细胞增殖细胞凋亡组织工程干细胞槲皮素胶质瘤干细胞增殖凋亡 STAT通路国家自然科学基金

Characteristics of temperature fluctuation in two-dimensional turbulent Rayleigh-Bénard convection

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Chinese Physics B 2022年第1期31卷 395-402页

作者： ming-Wei Fang Jian-chao He Zhan-chao Hu Yun bao School of Aeronautics and Astronautics Sun Yat-sen UniversityGuangzhou 510275China

We study the characteristics of temperature fluctuation in two-dimensional turbulent Rayleigh–Benard convection in´a square cavity by direct numerical *** Rayleigh number range is 1×10^(8)≤Ra≤1×10^(13),and the Prandtl number is selected as Pr=0.7 and Pr=*** is found that the temperature fluctuation profiles with respect to Ra exhibit two different distribution *** the thermal boundary layer,the normalized fluctuationθrms/θrms,max is independent of Ra and a power law relation is identified,i.e.,θrms/θrms,max∼(z/δ)0.99±0.01,where z/δis a dimensionless distance to the boundary(δis the thickness of thermal boundary layer).Out of the boundary layer,when Ra≤5×10^(9),the profiles ofθrms/θrms,max descend,then ascend,and finally drop dramatically as z/δ*** for Ra≥1×10^(10),the profiles continuously decrease and finally overlap with each *** two different characteristics of temperature fluctuations are closely related to the formation of stable large-scale circulations and corner ***,there is a critical value of Ra indicating the transition,beyond which the fluctuation hθrmsiV has a power law dependence on Ra,given by hθrmsiV∼Ra−0.14±0.01.

关键词： Rayleigh-Benard temperature fluctuation distribution patterns critical value

A new monoterpenoid indole alkaloid from Rauvolfia yunnanensis

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Chinese Chemical Letters 2009年第10期20卷 1221-1223页

作者： bao Hui Cheng Jian chao Chen ming Hua Qiu a State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

One new monoterpenoid indole alkaloid, l l-methoxyburnamine-17-O-3′,4′,5′-trimethoxybenzoate （1）, was isolated from Rauvolfia yunnanensis Tsiang. Its structure was identified by speclroscopic evidences.

关键词： Rauvolfia yunnanensis Monoterpenoid indole alkaloid Akuammiline-type rnonoterpenoid indole alkaloid

Prefrontal cortical α_(2A)-adrenoceptors and a possible primate model of attention deficit and hyperactivity disorder

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Neuroscience Bulletin 2015年第2期31卷 227-234页

作者： chao-Lin Ma Xuan Sun Fei Luo bao-ming Li Center for Neuropsychiatric Disorders Institute of Life Science Nanchang University

Attention deficit and hyperactivity disorder （ADHD）, a prevalent syndrome in children worldwide, is characterized by impulsivity, inappropriate inattention, and/or hyperactivity. It seriously afflicts cognitive development in childhood, and may lead to chronic under-achievement, academic failure, problematic peer relationships, and low self-esteem. There are at least three challenges for the treatment of ADHD. First, the neurobiological bases of its symptoms are still not clear. Second, the commonly prescribed medications, most showing short-term therapeutic efficacy but with a high risk of serious side-effects, are mainly based on a dopamine mechanism. Third, more novel and efficient animal models, especially in nonhuman primates, are required to accelerate the development of new medications. In this article, we review research progress in the related fields, focusing on our previous studies showing that blockade of prefrontal cortical a2A-adrenoceptors in monkeys produces almost all the typical behavioral symptoms of ADHD.

关键词： prefrontal cortex a2A-adrenoceptors cognitive functions attention deficit and hyperactivity disorder animal models

A note on the entropy of mean curvature flow

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Science China Mathematics 2015年第12期58卷 2611-2620页

作者： bao chao Key Laboratory of Pure and Applied Mathematics School of Mathematical SciencesPeking University

The entropy of a hypersurface is given by the supremum over all F-functionals with varying centers and scales, and is invariant under rigid motions and dilations. As a consequence of Huisken's monotonicity formula, entropy is non-increasing under mean curvature flow. We show here that a compact mean convex hypersurface with some low entropy is diffeomorphic to a round sphere. We also prove that a smooth selfshrinker with low entropy is a hyperplane.

关键词： entropy self-shrinker mean curvature flow sphere

Review of the first principles calculations and the design of cathode materials for Li-ion batteries

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Advances in Manufacturing 2014年第4期2卷 358-368页

作者： Liu-ming Yan Jun-ming Su chao Sun bao-Hua Yue Department of Chemistry College of SciencesShanghai University Department of Physics College of SciencesShanghai University

Cathode materials are the most critical chal- lenge for the large scale application of Li-ion batteries in electric vehicles and for the storages of electricity. The first principles calculations play an important role in develop- ment and optimization of novel cathode materials. In this paper, we overview the first principles calculations of energy, volume change, band-gap, phase diagram, and Li- ion transport mechanism of cathode materials with an emphasis on the design of such materials. We also over- view the recent progress of data mining techniques and the high-throughput first principles calculations for the design and development of cathode materials. Finally, we preview the challenges and opportunities of this rapidly developing field.

关键词： Materials design First principles Densityfunctional theory (DFT) Li-ion batteries Diffusioncoefficient

Gold-catalyzed ketene dual functionalization and mechanistic insights:divergent synthesis of indenes and benzo[d]oxepines

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Science China Chemistry 2021年第5期64卷 778-787页

作者： ming bao Jinzhou Chen chao Pei Sujie Zhang Jinping Lei Wenhao Hu Xinfang Xu Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery School of Pharmaceutical SciencesSun Yat-sen UniversityGuangzhou 510006China

An unprecedented gold-catalyzed ketene C=O/C=C bifunctionalization method has been *** studies and density function theory(DFT)calculations indicate that the reaction is initiated by gold-catalyzed Wolff rearrangement of diazoketone to form the ketene intermediate,followed by intermolecular nucleophilic addition and terminated with two divergent cyclization processes via enol *** the case with alcohols as the nucleophiles,the reaction goes through a C-5-endodig carbocyclization to give the indene products;whereas,O-7-endo-dig cyclization occurs dominantly when indoles/pyrroles are used as the nucleophiles,delivering the 7-membered benzo[d]*** comparison with the well-documented cycloaddition and nucleophilic addition reactions,this cascade reaction features a novel reaction pattern for the ketene dual functionalization through addition with nucleophile and electrophile in sequence.

关键词： metal carbene ketene dual functionalization Wolff rearrangement gold catalysis indene benzo[d]oxepine

Studies of Chemical Constituents and Their Antioxidant Activities From Astragalus mongholicus Bunge

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Biomedical and Environmental Sciences 2005年第5期18卷 297-301页

作者： DE-HONG YU YONG-ming bao chao-LIANG WEI, LI-JIA AN Department of Environment and Biology Dalian University of Technology Dalian 116024 Liaoning China

To evaluate the antioxidant activities of different chemical constituents from Astragalus mongholicus Bunge and their protection against xanthine （XA）/xanthine oxidase （XO）-induced toxicity in PC12 cells. Methods The compounds of Astragalus mongholicus Bunge were isolated by chromatography and the structures were elucidated on the basis of spectral data interpretation. Their antioxidant activities were detected by 1, 1-diphenyl-2-picrylhydrazyl （DPPH） radical scavenging activities in a cell-free system. Meanwhile, the effects against XA/XO-induced toxicity were assessed using MTT assay in PC12 cells. Results Ten principal constituents were isolated and identified as formononetin （Ⅰ）, ononin （Ⅱ）, calycosin （Ⅲ）, calycosin-7-O-β-D-glucoside （Ⅳ）, 9,10-dimethoxypterocarpan-3-O-β-D-glucoside （Ⅴ）, adenosine （Ⅵ）, pinitol （Ⅶ）, daucosterol （Ⅷ）, β-sitoster （Ⅸ） and saccharose （Ⅹ） from Astragalus mongholicus Bunge. The compounds Ⅰ, Ⅲ, and Ⅳ scavenged DPPH free radicals in vitro. Formononetin and calycosin were found to inhibit XA/XO-induced cell injury significantly, with an estimated EC50 of 50 ng/mL. Conclusion Compound Ⅲ, Ⅵ, and Ⅶ are first reported in this plant. Calycosin exhibits the most potent antioxidant activity both in the cell-free system and in the cell system.

关键词： Astragalus mongholicus Bunge Constituents Antioxidant PC12 Toxicity