全文获取类型
收费全文 | 25237篇 |
免费 | 1062篇 |
国内免费 | 19篇 |
出版年
2023年 | 136篇 |
2021年 | 230篇 |
2020年 | 423篇 |
2019年 | 508篇 |
2018年 | 670篇 |
2017年 | 643篇 |
2016年 | 733篇 |
2015年 | 500篇 |
2014年 | 670篇 |
2013年 | 2778篇 |
2012年 | 1137篇 |
2011年 | 1188篇 |
2010年 | 789篇 |
2009年 | 823篇 |
2008年 | 1124篇 |
2007年 | 1091篇 |
2006年 | 1055篇 |
2005年 | 930篇 |
2004年 | 928篇 |
2003年 | 911篇 |
2002年 | 883篇 |
2001年 | 419篇 |
2000年 | 409篇 |
1999年 | 397篇 |
1998年 | 377篇 |
1997年 | 361篇 |
1996年 | 291篇 |
1995年 | 306篇 |
1994年 | 291篇 |
1993年 | 275篇 |
1992年 | 261篇 |
1991年 | 258篇 |
1990年 | 239篇 |
1989年 | 218篇 |
1988年 | 193篇 |
1987年 | 213篇 |
1986年 | 209篇 |
1985年 | 256篇 |
1984年 | 268篇 |
1983年 | 231篇 |
1982年 | 234篇 |
1981年 | 256篇 |
1980年 | 226篇 |
1979年 | 209篇 |
1978年 | 222篇 |
1977年 | 195篇 |
1976年 | 197篇 |
1975年 | 158篇 |
1974年 | 180篇 |
1973年 | 140篇 |
排序方式: 共有10000条查询结果,搜索用时 7 毫秒
31.
David S. Geldmacher 《Brain and cognition》1996,32(3):405-415
Cancellation tests are commonly used in the clinical assessment of visuospatial function, but there has been little study of task characteristics influencing performance. This study was designed to assess factors which affect cancellation performance. Sixteen healthy subjects sequentially performed four random-array letter cancellation tasks. The forms contained 50 and 100 stimuli and target:distractor (T/D) ratios of 1:4 and 1:9 with target letter “A” and randomly selected letter distractors. The primary performance measure was calculated as the number of correctly cancelled targets divided by the time to complete the task, corrected for accuracy. This measure revealed a strong effect of T/D ratio (p< .0001), with performance adversely affected by higher proportion of distractors. There was no effect of stimulus number. This suggests that T/D ratio should be considered in cancellation test design and interpretation. 相似文献
32.
Informed by theory and research on attributions and narrative persuasion, we compared the effectiveness of narrative and nonnarrative messages in changing attributions of responsibility for causes and solutions related to obesity in the United States. We randomly assigned 500 adults to view one of three messages (narrative, evidence, and a hybrid of the two) emphasizing environmental causes of obesity, or a no‐exposure control condition. The narrative condition increased the belief that societal actors (government, employers) are responsible for addressing obesity, but only among liberals. This pattern of results was partially explained by the success of the narrative condition in reducing reactive counterarguing, relative to the evidence condition, among liberals. We conclude with theoretical and practical implications. 相似文献
33.
34.
35.
36.
37.
38.
Michael A Rapoff John Belmont Carol Lindsley Nancy Olson Judy Morris Joni Padur 《Health psychology》2002,21(6):620-623
Adherence to medications for chronic pediatric diseases decreases overtime. This randomized controlled trial evaluated a clinic-based, nurse-administered educational and behavioral intervention to prevent the anticipated drop in adherence to nonsteroidal medications among newly diagnosed patients with juvenile rheumatoid arthritis. Thirty-four participants completed the study (mean age = 8.44 years, SD = 3.96), including 19 in the experimental group and 15 in the standard-treatment (education) control group. There were significant group and Group x Time effects for adherence (assessed with an electronic monitor over a 13-month period) favoring the experimental group. In contrast, the groups did not differ significantly in disease activity or functional limitations. Factors that may have prevented detection of differences in these health parameters are dicussed. 相似文献
39.
40.