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   3530篇
  免费   130篇
  2022年   18篇
  2021年   19篇
  2020年   40篇
  2019年   57篇
  2018年   83篇
  2017年   78篇
  2016年   94篇
  2015年   81篇
  2014年   83篇
  2013年   360篇
  2012年   159篇
  2011年   154篇
  2010年   125篇
  2009年   108篇
  2008年   155篇
  2007年   184篇
  2006年   144篇
  2005年   120篇
  2004年   117篇
  2003年   133篇
  2002年   140篇
  2001年   66篇
  2000年   51篇
  1999年   71篇
  1998年   62篇
  1997年   54篇
  1996年   60篇
  1995年   40篇
  1994年   43篇
  1993年   43篇
  1992年   56篇
  1991年   45篇
  1990年   50篇
  1989年   35篇
  1988年   30篇
  1987年   33篇
  1986年   37篇
  1985年   38篇
  1984年   50篇
  1983年   36篇
  1982年   50篇
  1981年   39篇
  1980年   32篇
  1979年   31篇
  1978年   20篇
  1977年   29篇
  1976年   26篇
  1975年   14篇
  1974年   17篇
  1973年   14篇
排序方式: 共有3660条查询结果,搜索用时 46 毫秒
211.
These cancer genetic counseling recommendations describe the medical, psychosocial, and ethical ramifications of identifying at-risk individuals through cancer risk assessment with or without genetic testing. They were developed by members of the Practice Issues Subcommittee of the National Society of Genetic Counselors Cancer Genetic Counseling Special Interest Group. The information contained in this document is derived from extensive review of the current literature on cancer genetic risk assessment and counseling as well as the personal expertise of genetic counselors specializing in cancer genetics. The recommendations are intended to provide information about the process of genetic counseling and risk assessment for hereditary cancer disorders rather than specific information about individual syndromes. Key components include the intake (medical and family histories), psychosocial assessment (assessment of risk perception), cancer risk assessment (determination and communication of risk), molecular testing for hereditary cancer syndromes (regulations, informed consent, and counseling process), and follow-up considerations. These recommendations should not be construed as dictating an exclusive course of management, nor does use of such recommendations guarantee a particular outcome. These recommendations do not displace a health care provider's professional judgment based on the clinical circumstances of a client.  相似文献   
212.
Ethics has become an increasingly important issue within engineering as the profession has become progressively more complex. The need to integrate ethics into an engineering curriculum is well documented, as education does not often sufficiently prepare engineers for the ethical conflicts they experience. Recent research indicates that there is great diversity in the way institutions approach the problem of teaching ethics to undergraduate engineering students; some schools require students to take general ethics courses from philosophical or religious perspectives, while others integrate ethics in existing engineering courses. The purpose of this paper is to propose a method to implement the integration of ethics in engineering education that is pedagogically based on Kohlberg’s stage theory of moral development.  相似文献   
213.
The relationship between knowing where a haptic property is located and knowing what it is was investigated using a haptic-search paradigm. Across trials, from one to six stimuli were presented simultaneously to varying combinations of the middle three fingertips of both hands. Participants reported the presence/absence of a target or its location for four perceptual dimensions: rough/smooth, edge/no edge, relative position (right/left), and relative orientation (right/left). Reaction time data were plotted as a function of set size. The slope data indicated no difference in processing load for location as compared to identity processing. However, the intercept data did reveal a cost associated with processing location information. Location information was not obtained for "free" when identity was processed. The data also supported a critical distinction between material and edge dimensions versus geometric dimensions, as the size of the cost associated with processing location was larger for spatial than for intensive stimuli.  相似文献   
214.
The authors investigated affective semantic priming using a lexical decision task with 4 affective categories of related word pairs: neutral, happy, fearful, and sad. Results demonstrated a striking and reliable effect of affective category on semantic priming. Neutral and happy prime-targets yielded significant semantic priming. Fearful pairs showed no or modest priming facilitation, and sad primes slowed reactions to sad targets. A further experiment established that affective primes do not have generalized facilitatory-inhibitory effects. The results are interpreted as showing that the associative mechanisms that support semantic priming for neutral words are also shared by happy valence words but not for negative valence words. This may reflect increased vigilance necessary in adverse contexts or suggest that the associative mechanisms that bind negative valence words are distinct.  相似文献   
215.
This study extends the data on the efficacy of cognitive interventions for patients with chronic medical problems and describes the case of a 37-year-old woman with an anxiety disorder related to diabetes. The effects on panic frequency, use of safety behaviour and related beliefs were investigated after the introduction of two main cognitive-behavioral interventions. The results are consistent with predictions from the cognitive model of panic. This case demonstrates the usefulness of directly challenging the 'meaning' of the feared situation in order to produce clinically significant improvements in the management of physical disease.  相似文献   
216.
Traumatic aspects of the lives of John Bowlby and Margaret Mahler can be seen to inform their intellectual careers, a perspective that suggests that attachment theory and separation-individuation theory are far more consonant with one another than otherwise. Articulating the domains of convergence between the two theories reveals the essential complementarity of the special strengths of each. Both theories were attempts to understand the role of experience in the development of mental representations. Mahler paid close clinical attention to inner mental states and their evolution, while Bowlby searched for behavioral correlates that could lend themselves to empirical observation and inferences about internal representations.  相似文献   
217.
The aim of this study was to investigate the functional organisation of working memory and related cognitive abilities in young children. A sample of 633 children aged between 4 and 6 years were tested on measures of verbal short-term memory, complex memory span, sentence repetition, phonological awareness, and nonverbal ability. The measurement model that provided the best fit of the data incorporates constructs that correspond to the central executive, phonological loop, and episodic buffer subcomponents of working memory, plus distinct but associated constructs associated with phonological awareness and nonverbal ability.  相似文献   
218.
In this study, the authors confirm and expand previous findings (M. Anastasi, R. G. Sawyer, & P. J. Pinciaro, 1999; J. E. Lewis & R. M. Malow, 1997) concerning college students' knowledge and perceptions about HIV/AIDS. Although students are knowledgeable about HIV/AIDS, they have little personal concern about becoming infected and do not take appropriate safe sex precautions. Findings of the present study show that gender, ethnic background, and knowing someone infected by HIV/AIDS influence students' level of concern about infection. In addition, older students and those who know someone infected by HIV/AIDS are more likely to have been tested. Results are compared with national surveys of other age groups, and the authors suggest specific intervention strategies for college students.  相似文献   
219.
In this article, we address the effects on haptic recognition of common objects when manual exploration is constrained by using two kinds of rigid links--sheaths (Experiment 1A) and probes (Experiments 1B and 2). The collective effects of five different constraints are considered, including three from previous research (i.e., reducing the number of end effectors, wearing a compliant finger cover, and splinting the fingers; Klatzky, Loomis, Lederman, Wake, & Fujita, 1993) and from two current constraints (i.e., wearing a rigid finger sheath and using a rigid probe). The resulting impairments are interpreted in terms of the loss of somatosensory information from cutaneous and/or kinesthetic inputs. In addition, we relate the results to the design of haptic interfaces for teleoperation and virtual environments, which share some of the same reduction of sensory cues that we have produced experimentally.  相似文献   
220.
The number, amplitude, duration, and bout structure of isolation-induced ultrasonic vocalization (USV) of infant rats (Rattus norvegicus) were measured on postnatal Day 10. Measurements were made before and after a brief, 1-min, active interaction with their mother or before and after a "pick-up" control procedure. Consistent with prior studies, the number of USVs emitted was significantly increased in the period following the maternal reunion but not after the control procedure. The average amplitude of USVs was also greater following maternal reunion. Finally, analyses characterizing the bout structure of USV production indicated that the average bout size (i.e. number of USVs/bout) was increased severalfold following the reunion with the mother, accounting for the greater rate of USV production during the second isolation period.  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