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   62579篇
  免费   1710篇
  国内免费   17篇
  2020年   527篇
  2019年   650篇
  2018年   4104篇
  2017年   3534篇
  2016年   3031篇
  2015年   872篇
  2014年   897篇
  2013年   3758篇
  2012年   2003篇
  2011年   3736篇
  2010年   3302篇
  2009年   2326篇
  2008年   2957篇
  2007年   3407篇
  2006年   1259篇
  2005年   1322篇
  2004年   1210篇
  2003年   1092篇
  2002年   1063篇
  2001年   1280篇
  2000年   1244篇
  1999年   966篇
  1998年   499篇
  1997年   459篇
  1996年   428篇
  1995年   434篇
  1994年   411篇
  1993年   404篇
  1992年   795篇
  1991年   706篇
  1990年   758篇
  1989年   655篇
  1988年   693篇
  1987年   642篇
  1986年   652篇
  1985年   611篇
  1984年   568篇
  1983年   540篇
  1982年   394篇
  1980年   395篇
  1979年   601篇
  1978年   453篇
  1975年   501篇
  1974年   541篇
  1973年   565篇
  1972年   429篇
  1971年   412篇
  1969年   419篇
  1968年   497篇
  1967年   458篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
181.
Developmental dyslexia and word retrieval deficits   总被引:5,自引:1,他引:4  
Developmental dyslexics, selected on the basis of very slow naming rates on the Rapid Automatic Naming Tasks (RAN), were compared to normal readers on oral language, picture categorization, and reading tasks. Findings indicated that the dyslexics' word retrieval deficits were one symptom of a more generalized, however subtle, oral language deficit which involved both receptive and expressive oral language functioning. The dyslexics' word retrieval problem also seemed chiefly related to language processing and not to deficits in semantic memory as there were no significant differences between dyslexics and controls on a nonverbal semantic memory task (picture categorization). In naming and identifying printed words, the dyslexics appeared to rely considerably upon the "indirect" or "assembly-of-phonology" route; they were slower in naming irregularly spelled words compared to regularly spelled words and on a lexical decision task, the dyslexics were slower in making negative decisions for "pseudohomophones" (e.g., "braik") than for other matched nonwords. Results are discussed in terms of the logogen model with some consideration of a developmental model as well.  相似文献   
182.
Paul K. Moser 《Erkenntnis》1988,28(2):231-251
Epistemological probability is the kind of probability relative to a body of evidence. Many philosophers, including Henry Kyburg and Roderick Chisholm, hold that all epistemological probabilities reflect a relation between an evidential body of propositions and other propositions. But this article argues that some epistemological probabilities for empirical propositions must be relative to non-propositional evidence, specifically the contents of non-propositional perceptual states. In doing so, the article distinguishes between internalism and externalism regarding epistemological probability, and argues for a version of awareness internalism. The article draws three main concluding lessons. First, epistemological probability is not to be identified with the sort of objective, experience-independent probability that is familiar from statistical and propensity interpretations of probability. Second, it is doubtful that epistemological probability is measurable, in any useful way, by real numbers, even if it admits of comparative assessments. Third, contrary to the familiar claim of C. I. Lewis, epistemological probability should not be viewed as requiring a basis of certainty.  相似文献   
183.
184.
185.
Memory and awareness in a patient with multiple personality disorder   总被引:1,自引:0,他引:1  
We studied an individual with multiple personality disorder in whom each of several personalities claimed to have no direct awareness of the others and to be unable to consciously remember the experiences of other personalities. A broad selection of implicit and explicit memory tests was used to determine the extent to which one personality had access to knowledge acquired by another and the circumstances in which that knowledge would be expressed. The implicit assessment of memory was a necessary but not sufficient condition for demonstrating interpersonality access. The degree of compartmentalization of knowledge in this patient depended largely on whether the interpretation of presented information was likely to differ across personalities.  相似文献   
186.
The purpose of this investigation was to evaluate carefully smoking-related knowledge and beliefs and their relationships to smoking status in a large, heterogeneous sample of smokers and nonsmokers in two settings: (a) a large, biracial southern city and (b) a small midwestern community. Participants were 611 (198 male, 413 female) adult respondents to a random-dialing telephone survey in Fargo, North Dakota (n = 200), and Memphis, Tennessee (n = 411). Each participant was given the Smoking Attitudes Survey, which assesses generalized health beliefs as well as health-related problems associated with smoking. Participants' knowledge of smoking-associated diseases (e.g., lung cancer) and of diseases not associated with smoking (e.g., kidney stones) was assessed. Stepwise regression analysis of composite knowledge scores revealed four independent predictors of the health consequences of smoking: education, race, smoking status, and income. Smokers, compared to nonsmokers, reported less knowledge related to the health consequences of smoking, were more likely to be male, were less concerned with the health consequences of smoking, and were more concerned about the health consequences of cholesterol. The best predictor of smokers who had never attempted cessation was their greater concern over weight control when compared to smokers with a history of smoking cessation attempts. The results are discussed in terms of smoking prevention and intervention efforts.  相似文献   
187.
Previous studies suggest that anxiety and/or depressed mood are associated with recurrence of genital herpes lesions. The present study sought to extend the assessment of factors associated with genital herpes and to investigate the impact of psychological therapy on features of the disorder. Sixteen genital herpes patients received 5 weeks of either structured discussion or cognitive restructuring (CR) therapy in a group format. Measures of attitude about herpes, global coping, distress, loneliness, health locus of control, and recurrence frequency were administered at pretreatment, posttreatment, and 3 months follow-up. Patients also made daily reports during the 5 weeks of treatment from which information was extracted regarding their herpes symptoms, dysphoria, anxiety, and ongoing coping process. Therapy did not produce the expected reductions in reported distress or loneliness. The CR procedure, however, was associated with reduced frequency of lesion recurrence at follow-up. Avoidant coping was associated with lower recurrence rates, and loneliness scores were associated with higher recurrence rates. Prospective data indicated that recurrences were preceded by elevated anxiety that was independent of prodromal symptoms. These results provide support for the general proposals that psychological factors influence health status and that psychological intervention may reduce disease recurrence.  相似文献   
188.
Despite widespread popular belief in the activation of recurrent lesions in genital herpes simplex virus (HSV) by psychosocial stress, little empirical evidence supports that contention. This study retrospectively examined the role of stress in activation of HSV lesions as mediated by social support. Participants were 59 volunteers who had self-reported culture-positive genital HSV for at least 10 months. Measures of stress proneness (State-Trait Anxiety Inventory; STAI-Trait), recent stressful events (Schedule of Recent Events; SRE), and subjective appraisal of stress (global self-rating) were administered along with measures of general social support and herpes-specific social support. When retrospective reports of HSV symptoms were examined using a multiple-regression approach, duration of disease and amount of herpes-specific social support were found to be significant moderators of the relation between stress and number of HSV recurrences in the preceding 12 months. When duration of disease was short (less than 4 years), stress (SRE) and number of recurrences were positively associated; when disease duration was longer, there was no relationship. Similarly, at low levels of herpes-specific social support, a positive relation between stress (SRE) and number of recurrences was found. However, at higher levels of herpes-specific social support, no association was found. No relation was found between stress proneness (STAI-Trait) and HSV symptoms. However, subjective appraisal (global rating) of stress in the preceding 12 months was positively and significantly correlated with reported number of recurrences. Results are discussed in terms of their clinical implications.  相似文献   
189.
This study examined the independent and joint effects of cigarette smoking and caffeine consumption on blood pressure (BP) and heart rate (HR) reactions to stress in male and female college students. Following an initial physiological baseline, participants received one of four experimental treatments (paced smoking, caffeine, smoking plus caffeine, or neither) and had BP and HR measured before, during, and after two stressful tasks. The results revealed that, compared with the control condition, caffeine ingestion enhanced the magnitude of stress-induced systolic BP and HR reactions. Smoking combined additively with stress, and the joint effect of smoking and caffeine was no greater than either taken alone. Males and females were generally similar in their BP and HR responses to smoking, caffeine, and stress. Inconsistencies with previous research and possible physiological mechanisms underlying the observed effects are discussed.  相似文献   
190.
Analogical transfer, problem similarity, and expertise   总被引:6,自引:0,他引:6  
When we encounter a new problem, we are often reminded of similar problems solved earlier and may use the solution procedure from an old problem to solve a new one. Such analogical transfer, however, has been difficult to demonstrate empirically, even within a single experimental session. This article proposes a framework for conceptualizing analogical problem solving that can account for the conflicting findings in the literature. In addition, the framework leads to two predictions concerning the transfer behavior of experts and novices. These predictions concern both positive and negative transfer and are based on the different types of features included in the problem representations of experts and novices. First, when two problems share structural features but not surface features, spontaneous positive transfer should be more likely in experts than in novices. Second, when two problems share surface but not structural features, spontaneous negative transfer should be stronger for novices than for experts. These predictions were supported by the results of three experiments involving college students solving a complex arithmetic word problem.  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