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   40050篇
  免费   1486篇
  国内免费   18篇
  2020年   396篇
  2019年   410篇
  2018年   552篇
  2017年   564篇
  2016年   645篇
  2015年   498篇
  2014年   578篇
  2013年   2872篇
  2012年   1072篇
  2011年   1061篇
  2010年   702篇
  2009年   686篇
  2008年   974篇
  2007年   947篇
  2006年   838篇
  2005年   819篇
  2004年   746篇
  2003年   701篇
  2002年   747篇
  2001年   1279篇
  2000年   1258篇
  1999年   886篇
  1998年   403篇
  1997年   385篇
  1992年   793篇
  1991年   760篇
  1990年   781篇
  1989年   735篇
  1988年   670篇
  1987年   672篇
  1986年   683篇
  1985年   718篇
  1984年   625篇
  1983年   562篇
  1982年   416篇
  1981年   437篇
  1979年   632篇
  1978年   484篇
  1977年   420篇
  1976年   398篇
  1975年   588篇
  1974年   675篇
  1973年   701篇
  1972年   574篇
  1971年   560篇
  1970年   512篇
  1969年   552篇
  1968年   681篇
  1967年   656篇
  1966年   595篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
171.
172.
173.
Ratings of pre-morbid intelligence level, derived from the hospital charts of 26 chronic schizophrenics, were correlated with the post-mortem brain volume measures of cortex, white matter, central grey matter, and ventricles. Contrary to hypothesis, no significant correlations were found.  相似文献   
174.
This paper provides a review of recent Supreme Court decisions stemming from the implementation of voluntary AAPs that include preferential treatment as a remedy; the evidence and proof required to establish and defend against reverse discrimination claims is identified. Overall, the courts sanctioned the use of preferential treatment if it occured as part of a well-conceived AAP. However, differences were found in the manner in which the courts adjudicated Title VII and constitutional claims of preferential treatment. The discussion examines research on the potential effects of voluntary AAPs on important organizational and societal outcome variables. We conclude that the impact of AAPs is likely to be far-reaching, exerting an effect possibly well beyond the limits considered in court decisions.  相似文献   
175.
The aptitude tests used to help make personnel decisions about military recruits were validated against hands-on tests of job performance in two Marine Corps occupational specialties, radio repairers and automotive mechanics. The tests were administered by Marine Corps noncommissioned officers. Marine Corps units provided the test administrators, testing facilities, and examinees. Data collected under such conditions are filled with errors that reduce the accuracy of validity coefficients. This paper shows how validity coefficients can be made more accurate by exercising quality control during the statistical analysis.  相似文献   
176.
The IES Arrow-Dot was administered to 41 cocaine detoxification patients. This group's scores indicated lower ego functioning and higher impulsivity and superego functioning than other clinical samples. No significant differences were noted between the Arrow-Dot scores of patients who successfully completed the program and those who did not.  相似文献   
177.
Multidimensional studies of Munsell color solid   总被引:1,自引:0,他引:1  
  相似文献   
178.
Test theory without an answer key   总被引:2,自引:0,他引:2  
A general model is presented for homogeneous, dichotomous items when the answer key is not known a priori. The model is structurally related to the two-class latent structure model with the roles of respondents and items interchanged. For very small sets of respondents, iterative maximum likelihood estimates of the parameters can be obtained by existing methods. For other situations, new estimation methods are developed and assessed with Monte Carlo data. The answer key can be accurately reconstructed with relatively small sets of respondents. The model is useful when a researcher wants to study objectively the knowledge possessed by members of a culturally coherent group that the researcher is not a member of.This research was supported by NSF Grant No. SES-8320173 to the authors. We gratefully acknowledge comments and suggestions from John Boyd, Tarow Indow, and Kathy Maher as well as the editor and several anonymous referees.  相似文献   
179.
This paper gives a method for determining a sample size that will achieve a prespecified bound on confidence interval width for the interrater agreement measure,. The same results can be used when a prespecified power is desired for testing hypotheses about the value of kappa. An example from the literature is used to illustrate the methods proposed here.  相似文献   
180.
We obtain in this paper a representation of the formulae of extensions ofL by generalized quantifiers through functors between categories of first-order structures and partial isomorphisms. The main tool in the proofs is the back-and-forth technique. As a corollary we obtain the Caicedo's version of Fraïssés theorem characterizing elementary equivalence for such languages. We also discuss informally some geometrical interpretations of our results.  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