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毕培曦 江润祥 李钳 张宏达 Chang Kiaw-Lan Wong Khoon-Meng Gray Alexander I. Waterman Peter G. 《中国科学院研究生院学报》1988,26(3):205-210
通过化学分析证明，美栌木与九里香属内的九里香组植物较为接近，两者均含月橘烯碱
及8-戊烯化香豆精，而棕茎组植物则与黄皮属植物亲缘关系较近。 据此肯定了Tanaka的观
点，认为棕茎组比九里香组原始。黄皮族内的亲缘关系亦可作如下推断： 小芸木属→山小桔属→黄皮属→九里香属棕茎组→九里香属九里香组→美栌木属。 相似文献
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刘军 《内蒙古科技与经济》2011,(6):107-107,109
对欧亚百里香的根、茎、叶的结构进行了形态解剖研究,旨在阐明其内部结构的特点。所采用的研究方法为石蜡切片法,番红-固绿双重染色。对百里香属植物内部结构的形态研究从分类和合理利用上提供了一定的理论依据。 相似文献
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国产芸香科九里香属化学分类 总被引：1，自引：0，他引：1
九里香是芸香科的一个小属，主要分布于我国南部及中南半岛，少数个别品种向西南
延伸至印度和斯里兰卡及向东南伸展至澳洲东北部。 我国境内共有8种和1亚种。 九里香
属植物含丰富的生物碱和香豆精，其中包括不少生物活性成分，民间亦每每选用该属植物作传
统草药。最近又从千里香的根部分离得一种新的双吲哚生物碱，命名为月橘烯碱; 该成分有强
效的抗着床活性，对计划生育有重大意义。在发掘月橘烯碱的自然资源的研究过程中，作者分
析了国产的8种九里香属植物，发现该属植物可以划分为两组，即九里香组和棕茎组。九里香
组之成员跟棕茎组的在形态上有明显分别，而且前者之根部含抗着床成分月橘烯碱和8-戊烯
化香豆精，但后者之根部则含咔巴唑生物碱。初步分析了澳洲的卵叶九里香和泰国的暹罗九 里香，其形态及化学成分亦支持将该属分为两组。作者据此发表新组合。 相似文献
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爬山虎属植物利用研究 总被引：9，自引：0，他引：9
爬山虎属植物属于系葡萄科系多年生木质大藤本攀缘植物,全世界约有15种.爬山虎属植物生有粘性吸盘因此可以攀缘岩石、峭壁和墙壁等.本属植物适宜生活在阴湿的环境条件下,但是也不畏惧强烈的阳光.本属植物能够普遍生存于中国大部分土壤贫瘠、寒冷、干燥的恶劣生活环境中,若条件稍好生长则更加良好.本文对爬山虎属植物基本生物学性质以及爬山虎的具体生物学特性进行了描述,同时对国内外该属植物的研究状况进行了综述总结,其中重点叙述了爬山虎和五叶爬山虎的实际应用情况以及介绍了爬山虎及其它爬山虎属植物可以广泛应用于城市垂直绿化、绿化荒山以及治理风沙地中解决饲养家畜和绿化矛盾等用途并对该属植物的医药和食品研究应用前景提出了建议. 相似文献
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A research group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol-a chemical found in the skins of red grapes in red wine-can improve the sensitivity of mice to the hormone insulin according to a report in the October issue of Cell Metabolism.…… 《中国科学院院刊(英文版)》2008,22(1):14-15
Aresearch group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol--a chemical found in the skins of red grapes and in red wine--can improve the sensitivity of mice to the hormone insulin, according to a report in the October,2007 issue of Cell Metabolism. As insulin resistance is often characterized as the most critical factor contributing to the development of Type 2 diabetes, the findings“provide a potential new therapeutic approach for preventing or treating” both conditions, the researchers said. 相似文献
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Marjorie Armstrong-Stassen Margaret Landstrom Ramona Lumpkin 《The Information Society》1998,14(2):153-164
This study examined how students who had no prior experience with videoconferencing would react to the use of videoconferencing as an instructional medium. Students enrolled in seven different courses completed a questionnaire at the beginning of the semester and again at the end of the semester. Students at the origination and remote sites did not differ in their reactions toward videoconferencing but there was a significant difference for gender. Women reacted less favorably to videoconferencing. Compared to the beginning of the semester, students reported significantly less positive attitudes toward taking a course through videoconferencing at the end of the semester. There were no significant differences in students' attitudes toward videoconferencing across courses at the beginning of the semester but there were significant differences across the courses at the end of the semester. The results suggest the need for better preparation for both students and instructors. 相似文献
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A joint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology his co-workers from Norway US Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells suggesting that China's projected climate warming could decrease the pest's numbers. The study was published in Proceedings of the National Academy of Sciences on September .…… 《中国科学院院刊(英文版)》2008,22(1):6-7
Ajoint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology and his co-workers from Norway, US and Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells, suggesting that China＇s projected climate warming could decrease the pest＇s numbers. The study was published in Proceedings of theNational Academy of Sciences on 17 September, 2007. 相似文献
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Active biological molecules functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery disease diagnosis therapy new nanodevice construction.…… 《中国科学院院刊(英文版)》2008,22(1):22-22
Active biological molecules and functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery, disease diagnosis and therapy, and new nanodevice construction. 相似文献
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Caroline Haythornthwaite 《The Information Society》2001,17(3):211-226
A computer-mediated group is a complex entity whose members exchange many types of information via multiple means of communication in pursuit of goals specific to their environment. Over time, they coordinate technical features of media with locally enacted use to achieve a viable working arrangement. To explore this complex interaction, a case study is presented of the social networks of interactions and media use among members of a class of computer-supported distance learners. Results show how group structures associated with project teams dominated who communicated with whom, about what, and via which media over the term, and how media came to occupy their own communication niches: Webboard for diffuse class-wide communication; Internet Relay Chat more to named others but still for general communication across the class; and e-mail primarily for intrateam communication. Face-to-face interaction, occurring only during a short on-campus session, appears to have had a catalytic effect on social and emotional exchanges. Results suggest the need to structure exchanges to balance class-wide sharing of ideas with subgroup interactions that facilitate project completion, and to provide media that support these two modes of interaction. 相似文献
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《中国科学院院刊(英文版)》2008,22(1):2-3
CAS should stick to the principle of rendering service to, and giving impetus for, the development of China＇s science enterprise by making S＆T innovations, said CAS President LU Yongxiang. The CAS president made the remarks in a recent talk to communicate the gist of the winter session of the Party＇s Leading-member Group at CAS, which was held from 7 to 11 January in Beijing. 相似文献
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Electronic data interchange (EDI) provides means for interorganizational communication, creates network externalities, requires an advanced information technology (IT) infrastructure, and relies on standards. In the diffusion of such innovations, institutional involvement is imperative. Such institutions contain governmental agencies, national and global standardization organizations, local government, and nonprofit private organizations like industry associations. The last type of organizations we call intermediating institutions. They intermediate or coordinate ("inscribe") the activities of a group of would-be adopters. Unfortunately, little is known of how these organizations shape the EDI diffusion trajectory. In this article we examine one specific type of intermediating organizations?industry associations?and how they advanced the EDI diffusion process in the grocery sectors of Hong Kong, Denmark and Finland. We identify six institutional measures, placed into a matrix formed by the mode of involvement (influence vs. regulation) and the type of diffusion force (supply push vs. demand pull), that can be mobilized to further the EDI diffusion. Industry associations were found to be active users of all these measures to varying degrees. Their role was critical especially in knowledge building, knowledge deployment, and standard setting. Furthermore, institutional involvement varied due to policy and cultural contingencies and power dependencies. 相似文献
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《中国科学院院刊(英文版)》2008,22(1)
With great care, Dr. ZHOU Zhonghe takes out a package wrapped by cotton tissue from a drawer and says: "This is the gem of our collections: the fossil of a bird that lived 125 million years ago!" Then, pointing at a tiny mound, he explains: "Look, this is the claw and that is the head. It was in the egg shell and ready to hatch ... The species fell into a family of waterside inhabitants." 相似文献
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Leah A. Lievrouw 《The Information Society》2000,16(2):155-159
This essay focuses on universal service and the Internet as means to support social and political participation. The emphasis on access to telecommunications systems in conventional approaches to universal service is contrasted with access to content. A model of the information environment is described that accounts for the roles of content and conduit, both of which are necessary conditions to achieve true access. A method is outlined for employing information indicators to observe or measure the information environment. 相似文献
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Puay Tang 《The Information Society》1998,14(1):19-31
The increasing prospects of digital piracy has prompted the perceived need by electronic publishers to adopt technical systems of protection, and governments to reform their copyright laws. This article is a preliminary study of the management of intellectual property by electronic publishers, defined as those involved in the production of online databases, and CD-ROMs. It focuses on three main issues: (1) how electronic publishers view the increasing threat of piracy; (2) the methods of protection employed to protect intellectual property in digital format; and (3) the importance of technological protection of intellectual property in electronic publications. The analysis is based on a sample of 23 UK electronic publishers. The interviews revealed an interesting assortment of protection methods and did not show that technological protection was a preferred way. Instead, the means of protection, in addition to copyright law, comprised niche markets, pricing, trust, bad publicity, and nontechnical and technical means. 相似文献