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   3347篇
  免费   179篇
  国内免费   1篇
  2023年   34篇
  2022年   33篇
  2021年   52篇
  2020年   78篇
  2019年   102篇
  2018年   124篇
  2017年   133篇
  2016年   184篇
  2015年   82篇
  2014年   89篇
  2013年   362篇
  2012年   183篇
  2011年   214篇
  2010年   123篇
  2009年   116篇
  2008年   165篇
  2007年   154篇
  2006年   144篇
  2005年   111篇
  2004年   117篇
  2003年   113篇
  2002年   102篇
  2001年   50篇
  2000年   43篇
  1999年   39篇
  1998年   34篇
  1997年   30篇
  1996年   39篇
  1995年   39篇
  1994年   38篇
  1993年   19篇
  1992年   23篇
  1991年   23篇
  1990年   14篇
  1989年   14篇
  1988年   16篇
  1987年   16篇
  1985年   25篇
  1984年   19篇
  1983年   18篇
  1982年   25篇
  1981年   18篇
  1980年   15篇
  1979年   19篇
  1978年   11篇
  1977年   16篇
  1976年   14篇
  1975年   15篇
  1974年   14篇
  1973年   12篇
排序方式: 共有3527条查询结果,搜索用时 31 毫秒
981.
982.
In typical statistical learning studies, researchers define sequences in terms of the probability of the next item in the sequence given the current item (or items), and they show that high probability sequences are treated as more familiar than low probability sequences. Existing accounts of these phenomena all assume that participants represent statistical regularities more or less as they are defined by the experimenters—as sequential probabilities of symbols in a string. Here we offer an alternative, or possibly supplementary, hypothesis. Specifically, rather than identifying or labeling individual stimuli discretely in order to predict the next item in a sequence, we need only assume that the participant is able to represent the stimuli as evincing particular similarity relations to one another, with sequences represented as trajectories through this similarity space. We present experiments in which this hypothesis makes sharply different predictions from hypotheses based on the assumption that sequences are learned over discrete, labeled stimuli. We also present a series of simulation models that encode stimuli as positions in a continuous two‐dimensional space, and predict the next location from the current location. Although no model captures all of the data presented here, the results of three critical experiments are more consistent with the view that participants represent trajectories through similarity space rather than sequences of discrete labels under particular conditions.  相似文献   
983.
Given the range of pre-exposure prophylaxis (PrEP) products currently being tested to prevent HIV in women, a standardized Acceptability and Use of PrEP Products Among Women Tool may facilitate comparisons of product acceptability and use across different geographies, trials, and users. We conducted three rounds of cognitive interviewing over 2 months in 2016, with 28 South African women who had experience participating in a range of PrEP product trials. The final instrument contained 41 items, including five new items that improved construct validity and 22 items modified for clarity. Changes were made due to unclear wording, difficulty answering, participant embarrassment, low response variability, and administrative formatting. Cognitive interviewing provided a means to address issues that would have inhibited this tool's ability to accurately collect data otherwise. This rapid, low-cost study provided valuable insight into participants' understanding of questions and demonstrated the utility of cognitive interviewing in international clinical trials.  相似文献   
984.
Several clinical papers have provided clinical recommendations for how to provide cognitive behavioral therapy (CBT) for obsessive-compulsive symptoms among Orthodox Jewish individuals. However, no published studies have described culturally adapted CBT for anxiety or depression in this population or quantified the effectiveness of such approaches. We evaluated the effectiveness of CBT for symptoms of generalized anxiety and depression in a sample of Orthodox Jews (n = 65) and a comparison sample (n = 42) presenting to the Center for Anxiety, a private outpatient clinic with three offices in the New York area (www.centerforanxiety.org). A chart review revealed that all patients received CBT-based interventions with appropriate religious-cultural adaptations of treatment, which we present in two case studies. We observed statistically and clinically significant treatment gains from pretreatment to midtreatment (anxiety: t = 8.56, p < .001; depression: t = 8.01, p < .001), and again from midtreatment through termination (anxiety: t = 3.68, p < .001; depression: t = 3.62, p < .001). No significant differences in anxiety or depression were observed between Orthodox Jewish patients and controls at any time point or for treatment effects (anxiety: Wilks’ Lambda = .950, F = 2.65, p = .076, ηp2 = .050; depression: Wilks’ Lambda = .99, F = 2.00,p = .49, ηp2 = .014). This paper offers clinical insight into delivery of CBT to Orthodox Jewish patients, as well as preliminary support for the effectiveness of CBT in treating symptoms of generalized anxiety and depression within this population.  相似文献   
985.
986.
To clarify the relationship between sexual communication and sexual behavior, multiple components of sexual messages recalled from child hood were examined in a community sample of 248 African-American and White women. Respondents were matched on a predesignated set of demographic variables and were interviewed using the Wyatt Sexual History Questionnaire. We anticipated that women's recollections of messages from parents and television would differ both individually and across ethnicity, and that messages recalled from parents would be multidimensional, varying in tone (positive vs. negative) across time (childhood vs. adolescence) and form (verbal vs. nonverbal). We also expected that the presence and tone of specific types of messages re called would be associated with risk-related sexual behavior. Results confirmed predictions concerning differential interpretations of messages, and ethnicity emerged as a strong mediating variable. The implications of the specific types of parental messages influencing behavior are discussed.  相似文献   
987.
Recent research reveals a link between individual differences in mathematics achievement and performance on tasks that activate the approximate number system (ANS): a primitive cognitive system shared by diverse animal species and by humans of all ages. Here we used a brief experimental paradigm to test one causal hypothesis suggested by this relationship: activation of the ANS may enhance children’s performance of symbolic arithmetic. Over 2 experiments, children who briefly practiced tasks that engaged primitive approximate numerical quantities performed better on subsequent exact, symbolic arithmetic problems than did children given other tasks involving comparison and manipulation of non-numerical magnitudes (brightness and length). The practice effect appeared specific to mathematics, as no differences between groups were observed on a comparable sentence completion task. These results move beyond correlational research and provide evidence that the exercise of non-symbolic numerical processes can enhance children’s performance of symbolic mathematics.  相似文献   
988.
Churches are a promising setting through which to reach Latinas with cancer control efforts. A better understanding of the dimensions of religiousness that impact health behaviors could inform efforts to tailor cancer control programs for this setting. The purpose of this study was to explore relationships between dimensions of religiousness with adherence to cancer screening recommendations among church-going Latinas. Female Spanish-speaking members, aged 18 and older from a Baptist church in Boston, Massachusetts (N = 78), were interviewed about cancer screening behaviors and dimensions of religiousness. We examined adherence to individual cancer screening tests (mammography, Pap test, and colonoscopy), as well as adherence to all screening tests for which participants were age-eligible. Dimensions of religiousness assessed included church participation, religious support, active and passive spiritual health locus of control, and positive and negative religious coping. Results showed that roughly half (46 %) of the sample had not received all of the cancer screening tests for which they were age-eligible. In multivariate analyses, positive religious coping was significantly associated with adherence to all age-appropriate screening (OR = 5.30, p < .01). Additional research is warranted to replicate these results in larger, more representative samples and to examine the extent to which enhancement of religious coping could increase the impact of cancer control interventions for Latinas.  相似文献   
989.
Previous research has established the existence of active assortment, that is, a preference for similarity in a potential mate. Few studies, however, have directly related mate preferences to dyadic similarity by examining them in the same participants. We collected both similarity and mate preference data in two studies: undergraduate students (N = 519) and newlyweds (N = 335). In both studies, women placed a higher value on desirable personality characteristics (e.g., higher Conscientiousness and Agreeableness, lower Neuroticism) than did men. Nevertheless, our data also provided strong evidence of consensual mate preferences: Men and women both desired partners who were agreeable, conscientious, emotionally stable, intelligent, and physically attractive; furthermore, participants desired partners who were better (e.g., more agreeable and attractive) than they were. In contrast, attitudinal variables such as religiousness and political orientation displayed much weaker consensus but showed significant dyadic similarity in both samples; similarity coefficients for personality tended to be positive, but lower. Finally, analyses revealed a direct link between actual and desired similarity: Couples displayed the strongest similarity on those variables for which participants expressed the strongest preference for similarity. Our findings strongly suggest that active assortment is partly responsible for dyadic similarity.  相似文献   
990.
Participation in youth sports can be very beneficial, but children with Attention Deficit Hyperactivity Disorder (ADHD) may participate less often and less successfully. The current study evaluated functional sports outcomes for children with ADHD who attended an intensive behavioral treatment program that included a sports training component, and it compared outcomes to children with ADHD who did not attend the program. Results suggest that treatment resulted in significant improvements in many aspects of children’s sports functioning, including knowledge of game rules, in vivo game performance, and fundamental skill tasks (motor proficiency, ability to trap a soccer ball appropriately, reduced handball penalties in soccer, and improved ability to catch a baseball). Parents also reported improved sports skills and good sportsmanship in the treatment group. No differences between groups were evident on additional skill tasks evaluating accurately kicking a soccer ball, throwing a baseball, or hitting a baseball off a tee. These results suggest intensive behavioral intervention that includes sports training can significantly improve functional sports outcomes for young children with ADHD.  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