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   174865篇
  免费   7773篇
  国内免费   156篇
  182794篇
  2021年   1500篇
  2020年   2780篇
  2019年   3438篇
  2018年   3511篇
  2017年   4003篇
  2016年   4617篇
  2015年   3928篇
  2014年   4805篇
  2013年   23528篇
  2012年   4519篇
  2011年   3690篇
  2010年   3918篇
  2009年   4772篇
  2008年   3934篇
  2007年   3412篇
  2006年   4044篇
  2005年   4028篇
  2004年   3496篇
  2003年   3156篇
  2002年   2945篇
  2001年   3517篇
  2000年   3377篇
  1999年   3294篇
  1998年   2864篇
  1997年   2679篇
  1996年   2586篇
  1995年   2423篇
  1994年   2388篇
  1993年   2346篇
  1992年   2708篇
  1991年   2560篇
  1990年   2402篇
  1989年   2317篇
  1988年   2268篇
  1987年   2293篇
  1986年   2254篇
  1985年   2492篇
  1984年   2559篇
  1983年   2315篇
  1982年   2388篇
  1981年   2360篇
  1980年   2196篇
  1979年   2212篇
  1978年   2207篇
  1977年   2181篇
  1976年   1955篇
  1975年   2023篇
  1974年   2086篇
  1973年   1963篇
  1972年   1553篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
The field of applied behavior analysis has devoted considerable effort to the problem of educating America's youth. In addition to developing a wide range of procedures to improve children's academic and classroom survival skills, behavioral researchers have discussed a wide range of technological characteristics that are likely to facilitate the adoption of their procedures by educational decision-makers and practitioners. A movement to restructure American schools has become highly popularized within educational, political, and public media forums over the past several years. One general characteristic of this movement is its failure to recommend the more frequent implementation of applied behavior analysis techniques to educate America's youth. A close inspection of three global models for school reform, however, reveals notable compatibilities with the focus and goals of applied behavior analysis. Applied behavior analysts can collaborate with and contribute to the school restructuring movement by pursuing the more formal and systematic analyses of characteristics essential to the adoption process.  相似文献   
992.
Three commentaries are offered on the following case: George, age 57, is a previously healthy man who recently underwent surgery for removal of a low-grade malignant thymoma. At the time of admission to the hospital, George stressed to the staff that he had long ago signed a "living will," which he renewed immediately after he learned of his cancer diagnosis. At the time of surgery, the tumor was found to extend into his mediastinum; although it was removable, this required revision of part of the sternum and grafting of the vessels feeding the heart chambers. Because of the resultant tissue damage and neuronal hyperactivity, George experienced postoperative episodes of cardiac arrhythmia and bronchospasm. Unanimous medical opinion was that this situation was a temporary problem that would resolve itself as the tissues healed. Until that time, however, it will be difficult to wean him from ventilatory support. When his stay in the intensive care unit became prolonged, George and his family began to insist that his status be changed to "do not resuscitate" and reminded the staff about his longstanding living will. All of this is happening despite the fact that the patient and family seemingly comprehend that although the short-term interventions are invasive, there is a high probability of a successful outcome. George's cancer prognosis is excellent, and, although he may well have an episode of life-threatening arrhythmia, he is likely to respond to resuscitation interventions. Once the immediate postoperative period is over, his potential for a long and productive life with full capacities is excellent. Consider the following questions: (a) Should George's expressed wishes be respected, or should the staff take additional steps to help him survive the postoperative period, even if that means violating his stated wishes? and (b) What steps might the staff follow in sorting through this problem?  相似文献   
993.
994.
The emergence of the ethics consultation as a means to resolve moral crises in clinical medicine has revealed the need for a worksheet that would facilitate intake and analysis. The author developed the Bioethics Consultation Form as an attempt to remedy this need. The form is arranged in an outline format and is a useful asset to ethics committee discussions and record keeping. The first section covers basic intake data concerning the patient's medical and personal information, advance directives, and values, as well as the values of the physician and family. After the intake section is completed with the above data, the ethics consultant then turns to the analysis section. This second section allows for (1) the discussion of conflicting values, (2) the identification of priorities, and (3) the elucidation of ethical norms relevant to the case.The Bioethics Consultation Form was adopted by the Patient Care Advisory committee of the Franklin Square Hospital Center in Baltimore, Maryland in 1986. The methodology in the use of the form will be discussed. Further, the potential spectrum of consultative cases that can be analyzed using the form will be highlighted.  相似文献   
995.
Carol Gilligan has identified two orientations to moral understanding; the dominant ‘justice orientation’ and the under-valued ‘care orientation’. Based on her discernment of a ‘voice of care’, Gilligan challenges the adequacy of a deontological liberal framework for moral development and moral theory. This paper examines how the orientations of justice and care are played out in medical ethical theory. Specifically, I question whether the medical moral domain is adequately described by the norms of impartiality, universality, and equality that characterize the liberal ideal. My analysis of justice-oriented medical ethics, focuses on the libertarian theory of H.T. Engelhardt and the contractarian theory of R.M. Veatch. I suggest that in the work of E.D. Pellegrino and D.C. Thomasma we find not only a more authentic representation of medical morality but also a project that is compatible with the care orientation's emphasis on human need and responsiveness to particular others.  相似文献   
996.
Because physicians use scientific inference for the generalizations of individual observations and the application of general knowledge to particular situations, the Bayesian probability solution to the problem of induction has been proposed and frequently utilized. Several problems with the Bayesian approach are introduced and discussed. These include: subjectivity, the favoring of a weak hypothesis, the problem of the false hypothesis, the old evidence/new theory problem and the observation that physicians are not currently Bayesians. To the complaint that the prior probability is subjective, Bayesians reply that there will be ultimate convergence, but the rebuttal to this is that there will not be uniform convergence. Secondly, since the Bayesian scheme favors a weak hypothesis, theories turn out to be a gratuitous risk. The problem with the false hypothesis comes out in the denominator of the theorem, revealing that a factor which is not a theory at all is being considered in the reasoning. On the old evidence/new theory problem old evidence cannot confirm a new theory so that the posterior probability will equal the prior probability. Finally, empiric studies have shown that current physicians are not Bayesians. But on consideration of Bayesian inference as a system of inference, it can be reasoned that physicians should be Bayesians. However, the problem of physicians' and patients' own subjectivity continue to plague this system of medical decision making.  相似文献   
997.
Twenty years ago, William Kessen, Greta Fein and I developed and tested a model of parent education, a model which involved variation in curricular content, didactic approaches, and child outcomes–experimentally contrasted. Our experience yielded some valuable lessons about the extent to which researchers can influence parents' behaviour, and parents their children's development. In the present article I suggest that these lessons might be useful for researchers now as they were for us then. I present some observations about the research that developmental psychologists have done in the intervening two decades and suggest that we could learn much by using such a model of parent education to answer questions about the effets of parents' behaviour on children's development. Carefully done, parent education studies can yield valuable information about many of the questions raised in recent correlational research. Parent training research can suggest hypotheses that can be tested with data collected non-interventively and analysed in causal model analyses–and vice versa. What is more, because one reason for studying parent effects is so that we can offer guidance to parents about rearing their children, this design has a particular advantage; it is both the medium and the message.  相似文献   
998.
The American eugenics movement had a significant impact on American social history, and analysis of the movement illustrates the relationship among science, scientists, and society. The history of the American eugenics movement as well as more recent examples of eugenic thought and biological determinism are reviewed. The need for genetic counselors to confront eugenic issues in their own profession and in society is discussed.  相似文献   
999.
1000.
Genetic issues are demanding more attention in the area of public health. Adoption agencies and policymakers are beginning to address these issues where they relate to the adoption process and to the many families involved in adoption in this country. Genetic counselors need to play an active role as both educators of and consultants for adoption professionals and the families with whom they work. To facilitate a partnership between genetics and adoption we have developed a workshop intended to educate adoption professionals about the lifelong implications of genetic conditions on the adoption triad.  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