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A New Iridoid Glycoside from the Aerial Parts of Avicennia marina

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A New Iridoid Glycoside from the Aerial Parts of Avicennia m...

中国化学会第四届有机化学学术会议

作者： FENG, Yan LI, Xiao-Ming WANG, Bin-Gui (Key Laboratory of Experimental Marine Biology, Institute of Oceanology, chinese Academy of sciences, Qingdao 266071) (graduate School of chinese Academy of sciences, beijing 10003.)

＜正＞Avicennia marina, one of the abundant components of mangrove ecosystems, is a cosmopolitan species resident from eastern Africa to the Persian Gulf, through Indo-Melanesia, India, south-east Asia to china and Japan, and south through the Philippines and western Pacific Islands to Australia. In china, this species is mainly distributed along the southern and south-eastern coastlines. The barks, leaves and fruits of A. marina were used in traditional medicine to treat skin diseases. Iridoid glucosides, fatty acids, sterols, and hydrocarbons have previously been isolated from A. marina. The present communication deals with the isolation and structural elucidation of a new iridoid glycoside （1） from the aerial parts of this plant. The chemical structure of 1 was elucidated as 2’-O-（4"-hydroxycinnamoyl） mussaenosidic acid methyl ester by spectroscopic means.

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烙铁头蛇毒L-氨基酸氧化酶的分离、纯化及其生物学活性(英文)

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生物化学与生物物理学报 2003年第3期35卷 219-224页

作者：魏继福魏勤吕秋敏台红金扬王婉瑜熊郁良中国科学院昆明动物研究所动物毒素研究室中国科学院昆明动物研究所动物毒素研究室昆明650223 中国科学院研究生院北京10003. 昆明650223

通过DEAESephadexA 5 0阴离子交换柱 ,SephadexG 75分子筛 ,ResourseQ阴离子交换柱三步层析从湖南产的烙铁头蛇毒中分离、纯化得到一个L 氨基酸氧化酶 (TM LAO) ,它由两个非共价的亚基组成 ,每个亚基的分子量为 5 5kD。与台湾产的烙铁... 详细信息

通过DEAESephadexA 5 0阴离子交换柱 ,SephadexG 75分子筛 ,ResourseQ阴离子交换柱三步层析从湖南产的烙铁头蛇毒中分离、纯化得到一个L 氨基酸氧化酶 (TM LAO) ,它由两个非共价的亚基组成 ,每个亚基的分子量为 5 5kD。与台湾产的烙铁头蛇毒L 氨基酸氧化酶分子量 ( 70kD)不同。TM LAO的N末端氨基酸序列是ADNKNPLEECFRETNYEEFLEIAR ,与报道的蝰科的L 氨基酸氧化酶的相似性比眼镜蛇科的要高。TM LAO能抑制大肠杆菌、金黄色葡萄球菌和痢疾杆菌的生长 ,杀死肿瘤细胞以及诱导血小板聚集。这些活性能被过氧化氢酶所抑制 ,说明TM LAO生理学功能主要是通过酶反应产生的过氧化氢 (H2 O2 )介导的

关键词： L-氨基酸氧化酶烙铁头抗菌活性细胞毒性血小板聚集

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泥石流阵流及其活动规律

水土保持研究 2005年第6期12卷 242-244页

作者：倪化勇吕学军中国科学院成都山地灾害与环境研究所

阵流是黏性泥石流的主要运动形式.选择蒋家沟1987～1994年8年间运动过程完整,阵次明显并且观测资料齐全的50次典型泥石流作为研究对象,讨论泥石流阵流产生的原因,并统计分析泥石流阵流的活动规律和特征.通过对完整的泥石流暴发过程进行... 详细信息

阵流是黏性泥石流的主要运动形式.选择蒋家沟1987～1994年8年间运动过程完整,阵次明显并且观测资料齐全的50次典型泥石流作为研究对象,讨论泥石流阵流产生的原因,并统计分析泥石流阵流的活动规律和特征.通过对完整的泥石流暴发过程进行分析,发现泥石流阵流径流量与阵流频次之间存在幂律关系;通过对历年典型泥石流流量过程的分析,发现蒋家沟泥石流阵流活动具有多峰性与多时段性.对于进一步认识泥石流(尤其是黏性泥石流)的运动规律和运动特征具有重要参考价值.

关键词：泥石流阵流蒋家沟幂律规则流量过程线

Nondestructive Detection of Brown Core in chinese Pear 'Yali' by Transmission Visible-NIR Spectroscopy

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Nondestructive Detection of Brown Core in Chinese Pear 'Yali...

国际农业工程大会

作者： Runlin Tu, graduate Student College of Food Science and Nutritional Engineering, china Agricultural university, {3. 100083. china Donghai Han, Associate professor Xinxin Liu, graduate Student Zhaohui Wen, graduate Student

Brown core is an internal disorder sometimes seen in pears under controlled atmosphere (CA) storage. The symptoms are not externally recognizable and visible only after cutting the fruit. Development of nondestructive measurements of brown core of pears benefits the producers, processors, and packers. A technique using body transmittance in the (651-1282) nm region was evaluated as a nondestructive technique for identifying chinese pear ’Yali’ with brown core. Based on (651282) nm region, the discriminant analysis with Mahalanobis Distance

关键词： chinese Pear ’Yali’ grading visible-NIR spectroscopy nondestructive detection brown core

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比较美学发展前瞻

学习与探索 2000年第4期 62-67页

作者：赵连元首都师范大学中文系北京100089

比较美学不仅是多种文化语境中的比较、理解和对话，而且是维系人类美好的感情、信仰和理想的最佳纽带。由世界文化发展的大势所决定，比较美学在２０世纪从孕育到形成取得了长足的进展。在２１世纪，这必将大力发展和日臻成熟。其成熟... 详细信息

比较美学不仅是多种文化语境中的比较、理解和对话，而且是维系人类美好的感情、信仰和理想的最佳纽带。由世界文化发展的大势所决定，比较美学在２０世纪从孕育到形成取得了长足的进展。在２１世纪，这必将大力发展和日臻成熟。其成熟标志和发展眼机主要是；１．比较美学理论专著问世；２．在高等学府开设比较美学课程；３．比较美学高校重点高校中建立。

关键词：比较美学西方美学中国美学比较美学理论

microRNAs in early zebrafish development:from gastrulation cell movements to craniofacial skeleton

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microRNAs in early zebrafish development:from gastrulation c...

2012全国发育生物学大会

作者： Guozhu Ning~(1*),Xiuli Liu~(1*),Anming Meng~(1,2),Qiang Wang~1 1 State Key Laboratory of Biomembrane and Membrane Biotechnology,Institute of Zoology,chinese Academy of sciences, beijing,{3. 2 Tsinghua-Peking Center for Life sciences,School of Life sciences,Tsinghua university,beijing,{3.

The regulation of gene expression by microRNAs(miRNAs) plays a critical role in different cellular processes, including metabolism,apoptosis,differentiation,and *** of miRNA biogenesis by the loss of dicer in zebrafish maternal-zygotic dicer(MZdicer) mutants,causes abnormal morphogenesis during gastrulation,and reduces pharyngeal cartilage at later ***,the functional role and molecular mechanisms of miRNAs in regulating theses important developmental processes have not been ***,we show that mir206 is essential for normal gastrulation cell movements by regulating JNK2 phosphorylation through inhibition of prickle1a expression and mir92a acts to maintain Bmp activity during craniofacial skeleton formation by targeting ***,more or less amount of these miRNAs results in similar developmental defects,implying that an appropriate expression level of these miRNAs are required during early zebrafish development,from gastrulation cell movements to craniofacial skeleton. Conclusions:Our data discover that mir206 targets pk1a to modulate JNK2 activation during zebrafish gastrulation and mir92a-mediated regulation of nog3.is critical for ingeniously balancing Bmp signal activity during pharyngeal cartilage formation.

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Size- and shape-controlled synthesis of monodisperse Co nanoparticles from cobalt acetate by thermal decomposition

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Rare Metals 2009年第3期28卷 241-244页

作者： LIN Tao SHAO Huiping GUO Zhimeng LUO Ji HAO Junjie School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Monodisperse cobalt nanoparticles with relatively high coercivities were synthesized by thermal decomposition of cobalt acetate for the application of ultra-high density magnetic recording media. Without using any reducing agent, Co nanoparticles of 13.9-21.3.nm in size were prepared using various protecting agents and a high boiling point solvent trioctylamine. The Co nanoparticles prepared with the mixture of oleic acid, oleylamine, and polyvinylpyrrolidone （PVP） showed clear crystalline structure of face centered cubic, and their coercivity was measured to be 27.2 kA/m. PVP was effective in controlling particle growth while hindering agglomeration between the particles. The as-prepared Co nanoparticles with a moderate coercivity can be applicable to patterned media.

关键词： cobalt nanoparticles high coercivity cobalt acetate thermal decomposition

Characterization of neuronal death in a convulsant model of rats,induced by intrahippocampal injection of BmK I,a sodium channel-specific modulator

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Characterization of neuronal death in a convulsant model of ...

中国神经科学学会第四次会员代表大会暨第七届全国学术会议

作者： Jun YANG~1,Rong ZHAO~2,Chun-Chun WENG~1,Xu-Ying ZHANG~2,Jian-Wei ZHANG~1,Yong-Hua JI~(1,2*) 1 School of Life sciences,Shanghai university,Shanghai 200444,china 2 {3. School of the chinese Academy of sciences,Institute of Physiology,Shanghai Institutes for Biological sciences,chinese Academy of sciences,Shanghai 20003.,china

＜正＞BmK I,anα-like neurotoxin acting on receptor-3.of the voltage-gated sodium channel,has been demonstrated to evoke epileptic seizures in *** the present study,we investigated the hippocampus morphological alteration and cell loss during convulsions induced by intrahippocampal injection of BmK *** nissl staining results showed that high-dose BmK I produced a significant morphological change of hippocampus after BmK I administration into hippocampus *** 0.5ug/ul and 1ug/ul BmK I strongly reduced the number and density of pyramidal neurons in ipsilateral CA1, CA2,CA3.fields,but granule cells in the hilus of dentate gyrus were only decreased by 1ug/ul BmK I *** death was not detected in the contralateral *** present study indicated that the epileptic seizures induced by BmK I are associated with loss of focal hippocampal excessive *** may provide a potential model to elucidate underlying cellular mechanisms of channel-induced epileptogenesis.

关键词： neuronal death seizures BmK I nissl staining

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土壤侵蚀与水土保持科学重点研究领域与问题

水土保持学报 2004年第1期18卷 1-6,26页

作者：冷疏影冯仁国李锐刘宝元郑粉莉刘国彬王占礼杨勤科傅伯杰宋长青国家自然科学基金委员会中国科学院资源环境科学与技术局中国科学院水利部水土保持研究所北京师范大学

进入新世纪,我国土壤侵蚀与水土保持科学研究迎来了新的发展机遇和挑战。在分析我国土壤侵蚀与水土保持学科研究的社会需求、科学需求及其特殊性的基础上,指出了我国土壤侵蚀与水土保持科学研究中存在的主要问题,提出了该领域亟待解决... 详细信息

进入新世纪,我国土壤侵蚀与水土保持科学研究迎来了新的发展机遇和挑战。在分析我国土壤侵蚀与水土保持学科研究的社会需求、科学需求及其特殊性的基础上,指出了我国土壤侵蚀与水土保持科学研究中存在的主要问题,提出了该领域亟待解决的前沿科学问题,如土壤侵蚀过程与机理,土壤侵蚀预报模型,水土保持措施防蚀机理及其适用性,流域生态过程和水土保持措施配置,大尺度土壤侵蚀与水土保持的格局及其变化规律,土壤侵蚀与水土保持环境效应评价,土壤侵蚀研究新技术与方法等。

关键词：土壤侵蚀水土保持防蚀机理适用性流域生态过程