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   9021篇
  免费   341篇
  国内免费   24篇
  2020年   101篇
  2019年   113篇
  2018年   147篇
  2017年   169篇
  2016年   179篇
  2015年   138篇
  2014年   149篇
  2013年   870篇
  2012年   292篇
  2011年   302篇
  2010年   185篇
  2009年   190篇
  2008年   226篇
  2007年   212篇
  2006年   216篇
  2005年   206篇
  2004年   186篇
  2003年   184篇
  2002年   192篇
  2001年   239篇
  2000年   225篇
  1999年   197篇
  1998年   111篇
  1996年   91篇
  1993年   91篇
  1992年   147篇
  1991年   153篇
  1990年   145篇
  1989年   145篇
  1988年   126篇
  1987年   131篇
  1986年   134篇
  1985年   130篇
  1984年   135篇
  1983年   108篇
  1982年   103篇
  1981年   101篇
  1980年   102篇
  1979年   157篇
  1978年   104篇
  1976年   105篇
  1975年   120篇
  1974年   143篇
  1973年   136篇
  1972年   101篇
  1971年   116篇
  1970年   101篇
  1969年   124篇
  1968年   105篇
  1967年   118篇
排序方式: 共有9386条查询结果,搜索用时 15 毫秒
1.
2.
Rats received Pavlovian conditioning in which food was signalled by a visual stimulus, A+, an auditory stimulus, B+, and a compound composed of different visual and auditory stimuli, CD+. Test trials were then given with the compound AB. Experiments 1 and 2A revealed stronger responding during AB than during CD. In Experiment 2B, there was no evidence of a summation of responding during AB when A+ B+ training was conducted in the absence of CD+ trials. A further failure to observe abnormally strong responding during ABwas found in Experiment 3 for which the training trials with A+ B+ CD+ were accompanied by trials in which C and D were separately paired with food. The results are explained in terms of a configural theory of conditioning, which assumes that responding during a compound is determined by generalization from its components, as well as from other compounds to which it is similar.  相似文献   
3.
Serial pattern learning was investigated in a variation of the task introduced by Nissen and Bullemer (1987). We presented an asterisk at 1 of 4 spatial locations on each trial, and Ss either responded with a keypress or observed the event. The first 4 blocks contained 10 repetitions of a 10- or 16-element pattern, and the 5th block contained a random sequence. The difference in response time on the 5th random block and the previous patterned block served as an indirect measure of pattern learning. A direct measure was obtained in a final test block in which Ss predicted the next asterisk position. Equivalent learning occurred for responding and observing with indirect measures, but observation was superior with direct measures. These findings indicate that knowledge of serial order can develop through simple perceptual experience, and this is more available to deliberate recall than is knowledge acquired while responding.  相似文献   
4.
In an early study in the Journal of Applied Behavior Analysis, Rekers and Lovaas (1974) evaluated the Behavioral Treatment of Deviant Sex-role Behaviors in a Male Child. They investigated the use of reinforcement and punishment to target non-gender-conforming behaviors of a 5-year-old male child. This study was considered by some to be controversial and concerning, even near the time of publication (Nordyke et al. 1977; Winkler, 1977). The concerns focused on the ethicality of selecting non-gender-conforming behavior as a target response and the use of punishment for this type of response, particularly at the behest of parents when the young child was not seemingly distressed. The study has subsequently been used as empirical support for conversion therapy creating concerns about misinterpretation of the original article and harm to the LGBTQ+ community. This editorial reviews the concerns originally presented by Nordyke et al. (1977) and Winkler (1977) and issues an official Expression of Concern about the various harms that have been associated with this paper.  相似文献   
5.
6.
Cognitive neuropsychology provides a theoretical framework and methods that can be of value in the study of developmental disorders, but the "dissociation" logic at the centre of this approach is not well suited to the developmental context. This is illustrated with examples from specific language impairment. Within the developing language system there is ample evidence for interaction between levels of representation, with modularity emerging in the course of development. This means that one typically is seeking to explain a complex pattern of associated impairments, rather than highly selective deficits. For instance, a selective impairment in auditory processing can have repercussions through the language system and may lead to distinctive syntactic deficits that are seen in written as well as spoken language. Changes in the nature of representations and in the relationships between components of a developing system mean that cross-sectional data at a single point in development may be misleading indicators of the primary deficit. Furthermore, traditional cognitive neuropsychology places a disproportionate emphasis on representational (competence) deficits, with processing (performance) deficits being relatively neglected. Methods for distinguishing these two kinds of impairment are discussed, as well as other approaches for elucidating the underlying nature of developmental disorders.  相似文献   
7.
8.
9.
OBJECTIVE: Compare the efficacy of a multicomponent social support intervention to standard-of-care counseling on medication adherence among HIV-infected patients initiating antiretroviral therapy. DESIGN: Randomized controlled trial. Generalized estimating equations tested for differences in the percentage of participants achieving 90% adherence. MAIN OUTCOME MEASURES: Pill-taking, electronically monitored over 6 consecutive months; plasma viral load (VL), assessed at 3 and 6 months following initiation of therapy. RESULTS: Of 226 participants who were randomized and began the trial, 87 (38%) were lost to the study by 6 months. The proportion of adherent participants declined steadily over time, with no time by group interaction. Sustained adherence was associated with increased odds of achieving an undetectable VL (OR=1.78; 95% CI=1.01, 3.13). In intention-to-treat analyses, a larger proportion of the intervention group than the control group was adherent (40.15% vs. 27.59%, p=.02) and achieved an undetectable VL p=.04). However, the majority of participants who remained on study experienced some reduction in VL (>or=1-log drop or undetectable), regardless of experimental condition. CONCLUSION: The multicomponent social support intervention significantly improved medication adherence over standard-of-care counseling; evidence for improved virologic outcomes was inconsistent. Early discontinuation of care and treatment may be a greater threat to the health of HIV patients than imperfect medication-taking.  相似文献   
10.
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