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   89826篇
  免费   3338篇
  国内免费   32篇
  2020年   944篇
  2019年   1117篇
  2018年   2589篇
  2017年   2525篇
  2016年   2332篇
  2015年   1226篇
  2014年   1442篇
  2013年   7468篇
  2012年   2823篇
  2011年   3412篇
  2010年   2430篇
  2009年   2101篇
  2008年   2941篇
  2007年   3043篇
  2006年   2083篇
  2005年   1830篇
  2004年   1825篇
  2003年   1766篇
  2002年   1663篇
  2001年   2708篇
  2000年   2564篇
  1999年   1948篇
  1998年   920篇
  1997年   801篇
  1996年   965篇
  1995年   891篇
  1994年   871篇
  1993年   827篇
  1992年   1742篇
  1991年   1578篇
  1990年   1592篇
  1989年   1459篇
  1988年   1449篇
  1987年   1363篇
  1986年   1328篇
  1985年   1393篇
  1984年   1182篇
  1983年   1003篇
  1982年   789篇
  1979年   1193篇
  1978年   864篇
  1975年   1023篇
  1974年   1092篇
  1973年   1162篇
  1972年   1028篇
  1971年   935篇
  1970年   807篇
  1968年   1018篇
  1967年   893篇
  1966年   848篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
901.
The Sentencing Reform Act of 1984, which created the U.S. Sentencing Commission, required that the commisson consider prison capacity in drafting sentencing guidelines. As part of the commission's efforts to meet this requirement, we developed a computer simulation capable of projecting the impact of the commission's guidelines on future sentences and prison populations. According to our projections, “straight” probation sentences will be reduced significantly under the guidelines. However, reducing the use of probation will generate only modest demands on the prisons, and then mostly for community corrections phased in over the course of 5 years. We also project that, while average time served for violent offenses will increase substantially, average time served for most property crimes will remain largely the same. Finally, while we forecast that federal prison populations will grow markedly by the end of this century, this is more a result of the Anti-Drug Abuse Act of 1986 and the career offender provision of the Comprehensive Crime Control Act of 1984 than a result of the guidelines.  相似文献   
902.
We studied central-place foraging in rats (Rattus norvegicus) by placing food items that varied in size and weight at the ends of a 4-arm radial maze. In Experiments 1-3, rats increasingly tended to carry food to the center of the maze as the size of those items increased. Very large food items often were hoarded in the center. Rats consumed food faster on the arms than in the center, and rats traveled faster when carrying food than when not. Blocking arm entrances increased travel time between the center and the arms and decreased food carrying at every item weight except the largest. In Experiments 4-6, important conditions that influence the degree of food-carrying behavior were discovered; these were the intersection of maze arms, the presence of a conspecific, and the use of open vs. closed maze arms.  相似文献   
903.
Estimate the amount of frequency variation that affected individual and species recognition by song in territorial male field sparrows with field playbacks of neighbors' songs lowered in frequency in 6 increments between 324 and 1296 Hz. Males gave strong responses to neighbors' songs that had been lowered by about 400 Hz, which is about 11% of the mean midfrequency in field sparrow song. Territorial responses were eliminated when neighbors' songs were lowered by more than about 900 Hz. Thus, there is a fairly narrow range of frequencies within which field sparrow songs can vary while functioning in communication. Ss' responses appear to be constrained by the normal range of song frequency variation within the species, but the range of variability within songs of individuals did not influence the degree of frequency shift required to render neighbors' songs unfamiliar.  相似文献   
904.
Remedial strategies for children and adolescents with disabilities should have their roots in assessment. In this article the authors discuss improvements in assessment approaches, including new standards for psychological testing, updated and renormed cognitive assessments, and vocational assessments with increased ecological validity. The combined efforts of school psychologists, rehabilitation counselors, vocational evaluators, psychologists, and school counselors have yielded progress in the technical qualities of assessment and utilization. Through comprehensive and functional assessment, students with disabilities should find the transition from school to work with greater success.  相似文献   
905.
This article discusses the implications of the Downing and Roush (1985) model of feminist identity development for feminist therapy with women. Following a summary of the model, the potential pitfalls of feminist therapy with the passive-acceptant client are described, as well as potential issues at subsequent stages of the client's identity development. Suggestions are made regarding how to facilitate clients' movement to higher levels of development. Finally, a research agenda is proposed that suggests hypotheses to be tested that arise from applying this model to conducting therapy with women.  相似文献   
906.
Prior to assuming the upright crouching posture over their pups during nursing bouts, lactating rats typically engage in several oral behaviors, including nuzzling, licking and rearranging pups. By acutely depriving dams of various aspects of perioral stimulation from pups (with anesthesia of the mystacial pads or of the tongue, with mouth suturing, or with muzzling), we found the following: (1) Distal stimulation from pups maintains proximity-seeking behavior, but is insufficient to stimulate nursing behavior. (2) Lack of tongue feedback decreases pup licking and hastens the onset of crouching. (3) Snout, but not tongue, contact with pups is required for hovering over them. (4) The position of the dam while hovering over her litter enables the pups to gain access to her ventrum, thereby provoking her upright, crouching posture. (5) Older pups are capable of bypassing the dam's perioral attentions and stimulating crouching directly by burrowing under the dam's ventrum.  相似文献   
907.
908.
909.
This paper addresses the use of the weekly written summary with patients in group psychotherapy. In an effort to stimulate group process and effect cotherapist communication, the authors instituted this group recording in an ongoing psychodynamically oriented mixed adult group. While the utilization of this device did, in fact, stimulate the group process and became an important part of the group's life, the therapists additionally saw significant effects upon their working alliance. These included increased focused dialogue upon group dynamics, more purposeful planning for group interventions, and heightened awareness of the significance of interventions in the group.Ms. Bosman-Clark is formerly Clinical Instructor, Department of Psychiatry, Baylor College of Medicine.  相似文献   
910.
Brief group psychotherapy as a method of treating psychological aftereffects of retirement is still in its infancy. It is therefore still possible to outline the whole field in overview. This paper examines the dynamics of aging and the relevant literature, discusses the conceptual issues involved, and describes techniques employed with this specific population. The typical cluster of complaints is portrayed, the psychological stressors associated with retirement are analyzed, and the various group-therapeutic modalities developed to counteract them are described. Furthermore, the rationale, process and characteristics of short-term group psychotherapy in the treatment of adjustment difficulties to retirement are reviewed. The clinical application of this approach, the therapist's particular roles and the therapeutic impact of this method are delineated.He would like to thank his co-therapist, Mrs. Sophie Bielawski, Reg. O.T., for her support and helpful observations and Drs. J. Regan and E. Sunday for their advice on methodolody.  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