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   33703篇
  免费   1225篇
  国内免费   16篇
  2018年   519篇
  2017年   523篇
  2016年   567篇
  2015年   405篇
  2014年   485篇
  2013年   2662篇
  2012年   896篇
  2011年   963篇
  2010年   640篇
  2009年   644篇
  2008年   933篇
  2007年   901篇
  2006年   842篇
  2005年   760篇
  2004年   729篇
  2003年   786篇
  2002年   759篇
  2001年   786篇
  2000年   778篇
  1999年   656篇
  1998年   397篇
  1997年   396篇
  1996年   395篇
  1995年   383篇
  1992年   602篇
  1991年   586篇
  1990年   552篇
  1989年   520篇
  1988年   540篇
  1987年   521篇
  1986年   550篇
  1985年   536篇
  1984年   500篇
  1983年   459篇
  1982年   373篇
  1981年   389篇
  1979年   525篇
  1978年   455篇
  1977年   397篇
  1976年   421篇
  1975年   442篇
  1974年   530篇
  1973年   559篇
  1972年   417篇
  1971年   426篇
  1970年   391篇
  1969年   408篇
  1968年   488篇
  1967年   453篇
  1966年   448篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
301.
Guideline sentencing systems, including the new federal guidelines, have not settled on a clear conception of when and how a trial judge should explain sentences. Indeterminate sentencing systems did not have a tradition of written sentencing decisions and recent sentencing reforms do not focus on the trial judge's role. This article suggests the many advantages of written sentencing opinions. Initial experience under the federal sentencing guidelines bolsters the conclusion that written sentencing opinions in appropriate cases—including both sentences “within” guidelines and guideline “departures”—are the next step in the evolving law of sentencing and the best way to recognize trial judges as an essential engine of principled change.  相似文献   
302.
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   
303.
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   
304.
We have proposed a novel interactive procedure for performing decision analysis, called Robust Interactive Decision Analysis (RID), which permits a decision maker (DM) to voluntarily and interactively express strong (viz, sure) binary preferences for actions, partial decision functions, and full decision functions, and only imprecise probability and utility function assessments. These serve as INPUTS TO operators to prune the state probability space and decision space until an optimal choice strategy is obtained. The viability of the RID approach depends on a DM's ability to provide such information consistently and meaningfully. On a limited scale we experimentally investigate the behavioral implications of the RID method in order to ascertain its potential operational feasibility and viability. More specifically, we examine whether a DM can (1) express strong preferences between pairs of vectors of unconditional and conditional payoffs or utilities consistently; (2) provide imprecise (ordinal and interval) state probabilities that are individually as well as mutually consistent with the state probabilities imputed from the expressed strong preferences. The results show that a DM can provide strong individually and mutually consistent preference and ordinal probability information. Moreover, most individuals also appear to be able to provide interval probabilities that are individually and mutually consistent with their strong preference inputs. However, the several violations observed, our small sample size, and the limited scope of our investigation suggest that further experimentation is needed to determine whether and/or how such inputs should be elicited. Overall, the results indicate that the RID method is behaviorally viable.  相似文献   
305.
306.
Perceptual speed in adulthood: cross-sectional and longitudinal studies   总被引:3,自引:0,他引:3  
Cross-sectional data on age differences in perceptual speed are presented from the Seattle Longitudinal Study for the age range 22-91 years (N = 1,620, first assessed in 1977; N = 628, first assessed in 1984). In addition, 838 subjects were followed over the 7-year interval. Markers of perceptual speed were the Identical Pictures and Finding A's tests from the ETS Kit of Factor-Referenced Tests. Significant age differences, age changes, and cohort differences were found at both observed variable and latent construct levels. Cross-lagged correlations examine the role of perceptual speed in predicting later performance on other abilities (Verbal Meaning, Inductive Reasoning, Spatial Orientation, Number, and Word Fluency). When perceptual speed is partialled out of scores for these abilities, aging effects are reduced markedly for all abilities, but least for Spatial Orientation and Inductive Reasoning.  相似文献   
307.
Recent work has questioned whether a single job evaluation instrument can reliably measure jobs from different job families. To test this, a generalizability study was done to determine the reliability of three job evaluation instruments: one for male-dominated jobs, MIMA-Shop, one for female-dominated jobs, MIMA-office and one which evaluated both types, FES. Initial results indicated that the latter instrument suffered no loss in reliability, and that all three instruments were equally highly reliable. A second analysis evaluated the reliability of the FES for male-dominated jobs separately from the reliability of the FES for female-dominated jobs. These results indicated no significant difference in reliability for male-dominated jobs and for female-dominated jobs. Implications of these findings were discussed.A previous version of this paper was presented at the 95th Annual Convention of the American Psychological Association at New York City, August 1987.  相似文献   
308.
A microcomputer running a spreadsheet program makes an excellent visual aid for demonstrating statistical concepts and procedures. Some advantages of this setup over traditional visual aids are described. Several statistical demonstrations that I have found to work well are presented.  相似文献   
309.
Studies that compare objective data on communication activity to data provided in verbal reports have indicated that verbal report data are not as accurate as one might hope. Researchers of communication have used verbal reports as their primary source of data because it presents a cheap and easy way to collect the data. This paper presents an easy alternative involving the study ofelectronic communication: a method that allows the collection of objective information on electronic communication, thus avoiding the problems associated with self-reports. The paper reviews the available literature on the accuracy of self-reports of communication, presents the instrument used to collect the objective electronic communication data, and discusses some of the difficulties and limitations encountered in implementing a study using the instrument.  相似文献   
310.
Using bar code technology to automate data collection provides a rapid and reliable alternative to paper-and-pencil tracking or keyboard entry into pocket or laptop computer. An array of bar code symbols is printed on a data menu, with a unique symbol corresponding to each possible observation. Bar code symbols are scanned using hand-held readers, which record the event, log the observation time, and store data for transfer to a personal computer. Advantages of the bar code monitoring system include: (1) ease of use by staff with minimal technical training, (2) reduced data entry errors and increased entry speed, (3) reliable portable operation, and (4) low-cost hardware. While the bar code system described here is used for behavioral monitoring in a residential treatment setting for the developmentally disabled, with minimal modification this system can be adapted for use in a wide variety of research and clinical applications.  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