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   56142篇
  免费   1409篇
  国内免费   11篇
  2018年   3899篇
  2017年   3304篇
  2016年   2775篇
  2015年   635篇
  2014年   671篇
  2013年   3182篇
  2012年   1550篇
  2011年   3369篇
  2010年   3108篇
  2009年   2099篇
  2008年   2677篇
  2007年   3044篇
  2006年   949篇
  2005年   1067篇
  2004年   1021篇
  2003年   967篇
  2002年   951篇
  2001年   868篇
  2000年   855篇
  1999年   707篇
  1998年   479篇
  1997年   481篇
  1996年   439篇
  1995年   418篇
  1992年   652篇
  1991年   580篇
  1990年   589篇
  1989年   532篇
  1988年   551篇
  1987年   528篇
  1986年   555篇
  1985年   566篇
  1984年   550篇
  1983年   512篇
  1982年   425篇
  1981年   427篇
  1979年   530篇
  1978年   492篇
  1977年   426篇
  1976年   450篇
  1975年   470篇
  1974年   578篇
  1973年   568篇
  1972年   418篇
  1971年   424篇
  1970年   395篇
  1969年   424篇
  1968年   491篇
  1967年   440篇
  1966年   458篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
It is widely assumed that reinforcers are biologically relevant stimuli, or stimuli that have been associated with biologically relevant stimuli. However, brief, arbitrary stimuli have also been reported to have reinforcement-like effects, despite being unrelated to biologically relevant stimuli like food. The present study explored the potential reinforcement-like effects of brief stimuli across 5 experiments. In Experiments 1 through 4, pigeon subjects responded for food reinforcement and brief stimulus presentations in a 2-component multiple schedule. Neither baseline response rates nor resistance to change during disruption tests were systematically greater in a component with versus without brief stimulus presentations. Increasing the rate and duration of brief stimulus presentations in Experiment 4 did not reveal reinforcement-like effects when compared directly with food. In Experiment 5, pigeons chose between independent terminal links in a concurrent-chains procedure. Across conditions, varying the location, duration, and rate of brief stimulus presentations in the terminal links had no systematic effects on preference. In contrast, varying rates of food reinforcers resulted in large and reliable shifts in preference. Therefore, the present study found no systematic evidence that brief stimuli unrelated to food reliably increase response rates, resistance to change, or preference. These data demonstrate the value of systematic replication, and a behavioral momentum approach to assessing potential reinforcement-like effects.  相似文献   
42.
43.
Book reviews     
Arnold, M. Memory and the brain. Hillsdale, N. J.: Lawrence Erlbaum Associates. 1984. Pp. 532. ISBN 0-89859-290-9. £47.90.

Green, T. R. G., Payne, S. P. and van der Veer, G. C. (Eds.). The psychology of computer use.. London: Academic Press. 1983. Pp. 225. ISBN 0-12-2974204. $9.50.

Stunkard, A. J. and Stellar, E. (Eds.). Eating and its disorders. New York: Raven Press. 1984. Pp. 302. ISBN 0-89004-891-6. $58.50.

Spillmann, L. and Wooten, B. R. (Eds.) Sensory experience, adaptation, and perception: Festschrift for Zero Kohler. Hillsdale, N. J.: Lawrence Erlbaum Associates. 1984. Pp. xxvii + 748. ISBN 0 8985-3-218-6. £70.85.

Geschwind, N. and Galaburda, A. M. (Eds.)Cerebral dominance: The biological foundations. Cambridge, Mass.: Harvard University Press. 1984. Pp. 232. ISBN 0-674-10658-X. £24.35.

Annett, M. Left, right, hand and brain: The right shift theory. 1985. London and Hillsdale, N. J.: Lawrence Erlbaum Associates. Pp. xiii + 474. ISBN 0-86377418-5 £29.95.

Ericsson, K. A. and Simon, H. A. Protocol analysis: Verbal reports as data. Cambridge, Mass.: The M.I.T. Press. 1984. Pp. 426. ISBN 0-262-05029-3. £28.95.  相似文献   
44.
45.
46.
47.
48.
The authors used recursive partitioning methods to identify combinations of baseline characteristics that predict 2-year physical activity success in each of 3 physical activity interventions delivered in the multisite Activity Counseling Trial. The sample consisted of 874 initially sedentary primary care patients, ages 35-75 years, who were at risk for cardiovascular disease. Predictors of 2-year success were specific to each intervention and represented a range of domains, including physiological, demographic, psychosocial, health-related, and environmental variables. The results indicate how specific patient subgroups (e.g., obese, unfit individuals; high-income individuals in stable health) may respond differently to varying levels and amounts of professional assistance and support. The methods used provide a practical first step toward identifying clinically meaningful patient subgroups for further systematic investigation.  相似文献   
49.
This study evaluated cardiovascular responses (CVR) to an active speech task with blatantly discriminatory (BRC) versus neutral (NRC) stimuli and an anger recall task in a sample of Black men (N = 73; age 18 to 47). Diastolic blood pressure scores were higher for NRC versus BRC stimuli during anger recall (p = .05). Moreover, persons in the NRC group who perceived high levels of racism (vs. no racism or BRC group) during active speech showed larger increases in blood pressure across postspeech rest, anger recall, and subsequent rest (p = .03). The notable elevation in CVR in response to an ambiguous event extends current models of racism suggesting that subtle racism is a psychosocial stressor that erodes health through chronically elevated CVR.  相似文献   
50.
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