首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   62372篇
  免费   1258篇
  国内免费   7篇
  63637篇
  2020年   582篇
  2019年   635篇
  2018年   834篇
  2017年   889篇
  2016年   988篇
  2015年   770篇
  2014年   869篇
  2013年   4250篇
  2012年   1648篇
  2011年   1637篇
  2010年   1064篇
  2009年   1020篇
  2008年   1495篇
  2007年   1432篇
  2006年   1245篇
  2005年   1214篇
  2004年   1137篇
  2003年   1084篇
  2002年   1109篇
  2001年   1822篇
  2000年   1763篇
  1999年   1282篇
  1998年   617篇
  1992年   1248篇
  1991年   1185篇
  1990年   1186篇
  1989年   1087篇
  1988年   1044篇
  1987年   1021篇
  1986年   1073篇
  1985年   1183篇
  1984年   941篇
  1983年   865篇
  1982年   611篇
  1981年   644篇
  1980年   564篇
  1979年   1053篇
  1978年   706篇
  1977年   664篇
  1976年   654篇
  1975年   927篇
  1974年   1061篇
  1973年   1103篇
  1972年   962篇
  1971年   912篇
  1970年   893篇
  1969年   878篇
  1968年   1141篇
  1967年   1050篇
  1966年   952篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
931.
Feminist legal theory provides a healthy skepticism toward legal doctrine and insists that we reexamine even formally gender-neutral rules to uncover problematic assumptions behind them. The article first outlines feminist legal theory from the perspectives of liberal, cultural, and radical feminism. Examples of how each theory influences legal practice, case law, and legislation are highlighted. Each perspective is then applied to a contemporary bioethical issue, egg donation. Following a brief discussion of the common themes shared by feminist jurisprudence, the article incorporates a narrative reflecting on the integration of the common feminist themes in the context of the passage of the Maryland Health Care Decisions Act. The article concludes that gender does matter and that an understanding of feminist legal theory and practice will enrich the analysis of contemporary bioethical issues.  相似文献   
932.
The World-Wide Web provides an inviting opportunity to reach large numbers of people, both as an audience for psychoacoustical discussions and demonstrations and as subjects for psychoacoustical experiments. Such use of the Web poses a unique set of challenges. We present the methodologies used to prepare a multimedia primer in auditory perception at McGill University. As well as instructional material, this primer includes acoustical experiments conducted over the Web. We discuss the response and experiences with this site in general and in a particular class situation at Hanover College.  相似文献   
933.
This article reports of the activities of the working group, Ethics & Engineers, of the Royal Flemish Society of Engineers. More particularly, the ethical problems that engineers face in the preparation of an environmental report are illuminated. Irrespective to which party the engineer belongs, he or she is confronted with the difficult weighting of his or her personal interest, the interests of private companies and last but not least the common good. It is argued that the implementation of a code of ethics and the introduction of courses on engineering ethics into the education of engineers would strengthen the engineer in the fulfilment of his vocation. Dirk Holemans is a bio-engineer preparing a doctoral thesis on the social responsibility of engineers, Herman Lodewyckx teaches ethics and has research interests in professional and applied ethics.  相似文献   
934.
Exposure to numerical examples (seed facts) produced a substantial long-term reduction in domain-specific innumeracy. In particular, learning the populations of 24 seed countries improved accuracy of estimates of the populations of 75 untrained countries, both at the time of learning and 4 months later. Consistent with abstraction-based theories of learning and memory, the benefits of having been exposed to the seed facts were as large 4 months after the exposure as immediately after it, despite the specific populations of the seed countries having been forgotten during the interval.  相似文献   
935.
This paper makes the assumption that organ transplantation is, under some conditions at least, a proper use of communal medical resources. Proceeding from this assumption, the author: (1) sketches the history of the problem; (2) briefly examines the prevalent models of communal structure and offers an alternate version; (3) discusses notions of justice and obligation derived from these different models; (4) applies these to the practice of harvesting organs for transplantation; and then (5) offers a different process for harvesting organs from the newly dead. If community is viewed as united by a set of shred goals and common values among which the value of community itself is important, then certain reciprocal obligations among members obtain. I suggest that routine salvage of organs from the newly dead be instituted but that it be routine salvage “with a twist”: rather early in life all members of the community are given the opportunity to refuse but their refusal carries the reciprocal condition that they cannot later become the recipients of that which they refuse to others.  相似文献   
936.
An aftereffect of perceived texture density contingent on the color of a surrounding region is reported. In a series of experiments, participants were adapted, with fixation, to stimuli in which the relative density of two achromatic texture regions was perfectly correlated with the color presented in a surrounding region. Following adaptation, the perceived relative density of the two regions was contingent on the color of the surrounding region or of the texture elements themselves. For example, if high density on the left was correlated with a blue surround during adaptation (and high density on the right with a yellow surround), then in order for the left and right textures to appear equal in the assessment phase, denser texture was required on the left in the presence of a blue surround (and denser texture on the right in the context of a yellow surround). Contingent aftereffects were found (1) with black-and-white scatter-dot textures, (2) with luminance-balanced textures, and (3) when the texture elements, rather than the surrounds, were colored during assessment. Effect size was decreased when the elements themselves were colored, but also when spatial subportions of the surround were used for the presentation of color. The effect may be mediated by retinal color spreading (Pöppel, 1986) and appears consistent with a local associative account of contingent aftereffects, such as Barlow’s (1990) model of modifiable inhibition.  相似文献   
937.
Fetal brain tissue from the occipital or the frontal cortex was implanted into the damaged occipital cortex of adult rats. The animals receiving grafts of embryonic frontal cortex showed partial restoration of brightness discrimination while recipients given homologous implants of occipital cortex were as impaired as those animals with lesions alone. Neither frontal nor occipital grafts aided in the performance of a pattern discrimination problem; both groups of brain-damaged animals were unable to learn the task. Nonetheless, both groups of animals had viable and enlarged grafts with similar neuronal and glial profiles.  相似文献   
938.
The purpose of this paper is to review the necessary components of a comprehensive group therapy program. The balancing between the didactic and the experiential portions, and an analysis of the selection criteria, along with the rationale for a particular sequencing of elements in the curriculum, are discussed. A line between supervision and personal therapy is drawn. The author describes the milieu necessary for a successful training program to evolve and makes suggestions for improvements. The various experiential aspects of training are presented and critically evaluated. The training situation is examined from the point of view of the faculty, the trainee and the patients involved. The author marshalls evidence indicating that personal group psychotherapy in a patient group is the preferred form for most trainees for the experiential part of the program. The paper concludes that the sharing and cohesiveness of training philosophies and methods by the faculty is a prerequisite to the success of any training program.  相似文献   
939.
940.
‘The authors discuss the dynamics of suicide, how to work with a potentially suicidal client in the counseling relationship, and legal and ethical implications for the counselor.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号