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分类学是认识生物体的一种工具,对生物体间系统关系的理解,种质资源利用的指南,也是一种交流用的普通语言.因此,分类处理需要反映这些关系的近期认识.在自然界,生物体只有两个绝对的单位:个体与种.一个种是一群个体被不可缺少的生殖关系相互联系成为的一个绝对单位.生殖隔离是种与种间的基本界限,同时也是生物演化过程中形成独立基因库(gene pools)的惟一因素.既然在种以上的分类群没有绝对界线,在种以上的任一分类处理都不可能避免人为性.虽然如此,仍然必须作出某些分类适应它们的描述、利用与(或)研究.这篇文章对小麦族分类群间生物系统关系的划分是基于遗传学的研究.我们分类处理的原则是:(1)反映这些种系统演化现今的理解;(2)便于种质资源的利用;(3)避免与传统处理有不必要的剧烈改变.  相似文献   

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Summary The research presented here was designed to investigate the mode of inheritance of fat and lean tissue deposition, and the relationship between them and body weight in Japanese quail. Heterotic effects were found for weight, size, and number of adipocytes in the abdominal fat depots, weight of the sartorial fat depot and percentage carcass fat with means for the hybrids being lower than those for the parental lines. General inferences concerning the importance of nonadditive genetic variation for lean and body weight were precluded due to inconsistencies observed among mating combinations. Thus, although heterosis and recombination effects were general for characteristics associated with fat deposition, the situation for body weight and lean was unique to the populations involved. It may be hypothesized that heterosis in the efficiency of feed utilization is reflected by the heterosis for fat deposition which explains why hybrids utilize feed better than their parental lines.  相似文献   

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The Politics of Egalitarianism: Theory and Practice . Jacqueline Solway, ed. New York: Berghahn, 2006. 260 pp.  相似文献   

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The Rousing Drum: Ritual Practice in. Japanese Community. Scott Schnell. Honolulu: University of Hawai'i Press, 1999. 363 pp.  相似文献   

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Under the Shadow of Nationalism: Politics and Poetics of Rural Japanese Women. Mariko Asano Tamanoi. Honolulu: University of Hawaii Press, 1998. 273 pp.  相似文献   

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对遗传学双语教学的教材选择,教学内容,教学手段和方法,考核办法及教学效果等进行了探讨和总结,并分析了双语教学改革所面临的问题,提出了双语教学改革应该在教务管理部门统一组织下,立足于本校的办学条件,从低年级开始系统地开展,任课教师根据师生的英语水平,积极摸索教改之路。  相似文献   

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The Synthetic Theory of Evolution (SyntheticDarwinism) was forged between 1925 and 1950.Several historians of science have pointed outthat this synthesis was a joint venture ofSoviet, German, American and Britishbiologists: A fascinating example of scientificcooperation, considering the fact that theevolutionary synthesis emerged during thedecades in which these countries were engagedin fierce political, military and ideologicalconflicts. The ideological background of itsAnglo-American representatives has beenanalyzed in the literature. We have examinedthe scientific work and ideological commitmentsof the German Darwinians during the ThirdReich. We based our analysis on four criteria:1) General attitude towards the Third Reich. 2) Membership in the NSDAP and other nationalsocialist organizations. Endorsement anddisapproval of the state ideology in 3) scientific and 4) other publications. We willmainly discuss the various authors that havecontributed to Die Evolution derOrganismen (1943), a collection thatrepresented the evolutionary synthesis inGermany. Most of the authors promoted eugenicideas, but not all of them adopted the racistinterpretation of the Third Reich. Anotherfinding is that there existed no directconnection between party membership andpromotion of the state ideology.  相似文献   

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染色体重组与连锁互换是遗传学教学的重点和难点。为使学生更好地理解此方面知识, 我们课题组前期利用图位克隆(map-based cloning)技术, 克隆了1个调控水稻(Oryza sativa)类病变表型的基因SPL5, 并基于此设计了一个新的综合型遗传学实验, 即利用DNA分子标记对基因进行定位。实验中学生利用水稻spl5突变体与野生型杂交获得的F2代定位群体和多态性分子标记, 对spl5突变进行染色体连锁分析、初步定位和遗传作图。该教学实验不仅可有效促进学生对遗传学三大定律的理解, 而且对其开阔视野、提高解决问题和团队协作的能力也有促进作用。  相似文献   

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染色体重组与连锁互换是遗传学教学的重点和难点。为使学生更好地理解此方面知识, 我们课题组前期利用图位克隆(map-based cloning)技术, 克隆了1个调控水稻(Oryza sativa)类病变表型的基因SPL5, 并基于此设计了一个新的综合型遗传学实验, 即利用DNA分子标记对基因进行定位。实验中学生利用水稻spl5突变体与野生型杂交获得的F2代定位群体和多态性分子标记, 对spl5突变进行染色体连锁分析、初步定位和遗传作图。该教学实验不仅可有效促进学生对遗传学三大定律的理解, 而且对其开阔视野、提高解决问题和团队协作的能力也有促进作用。  相似文献   

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Those seeking to ensconce themselves at the pinnacles of emerging sociopolitical hierarchies must forge alliances with both their immediate subordinates and distant peers. In the first case, allegiance to a polity that transcends extant and emerging sectarian affiliations must be achieved if the realm is to survive the passing of individual charismatic rulers. Cooperation with foreign leaders, in turn, guarantees a steady supply of political valuables useful in ensnaring clients within dependency relations that undergird sociopolitical hierarchy. Achievement of these objectives requires creation and propagation of at least two distinct social identities, one linking rulers and ruled within a polity and the other uniting paramounts in a network covering vast territorial expanses. In this article, we examine Late Classic (A.D. 600-950) material patterns from the Naco valley, northwestern Honduras, for the light they shed on the proposed integration of political and cultural processes within developing complex polities. The strategic manipulation of material symbols to fashion new affiliations and the implications of these identities for social change are also considered, [social identity, Mesoamerican archaeology, ideology, political contests, symbols]  相似文献   

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Abstract

This article explores the processes through which the advances of genetic research are incorporated into public health care in Denmark. Drawing on ethnographic fieldwork in cancer genetic counselling, the implementation of new medical advances is investigated by following the establishment of a policy on informing relatives at risk of hereditary cancer. This case material provides the occasion to examine how policies are shaped in a governmental process through which different actors seek to establish a common goal for a specific health practice. The struggle to define such a goal implies a struggle to define where to draw the line between health and disease and what makes up a healthy person in the context of genetic knowledge. The authors argue that in the process of establishing a policy in the field of cancer genetics the imperative of prevention comes to provide the framework within which an ethics of rights and responsibilities is constituted and the target group of cancer genetic counselling defined. This ethics is not determined by or inherent in genetic technology itself, but constituted in a social process and therefore negotiated within pre-existing frameworks of understanding in professional practice.  相似文献   

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Genetics and prevention: a policy in the making   总被引:1,自引:0,他引:1  
This article explores the process through which the advances of genetic research are incorporated into public health care in Denmark. Drawing on ethnographic fieldwork in cancer genetic counselling, the implementation of new medical advances is investigated by following the establishment of a policy on informing relatives at risk of hereditary cancer. This case material provides the occasion to examine how policies are shaped in a governmental process through which different actors seek to establish a common goal for a specific health practice. The struggle to define such a goal implies a struggle to define where to draw the line between health and disease and what makes up a healthy person in the context of genetic knowledge. The authors argue that in the process of establishing a policy in the field of cancer genetics the imperative of prevention comes to provide the framework within which an ethics of rights and responsibilities is constituted and the target group of cancer genetic counselling defined. This ethics is not determined by or inherent in genetic technology itself, but constituted in a social process and therefore negotiated within pre-existing frameworks of understanding in professional practice.  相似文献   

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Nationalism, Politics, and the Practice of Archaeology. Philip L. Kohl and Clare Fawcett. eds. Cambridge: Cambridge University Press, 1995. 329 pp.  相似文献   

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