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   78712篇
  免费   2473篇
  国内免费   18篇
  2020年   586篇
  2019年   783篇
  2018年   4218篇
  2017年   3576篇
  2016年   3189篇
  2015年   991篇
  2014年   1028篇
  2013年   4495篇
  2012年   2315篇
  2011年   4128篇
  2010年   3511篇
  2009年   2561篇
  2008年   3275篇
  2007年   3702篇
  2006年   1608篇
  2005年   1600篇
  2004年   1456篇
  2003年   1304篇
  2002年   1369篇
  2001年   1996篇
  2000年   1992篇
  1999年   1491篇
  1998年   710篇
  1997年   633篇
  1996年   623篇
  1993年   558篇
  1992年   1240篇
  1991年   1137篇
  1990年   1134篇
  1989年   1028篇
  1988年   1013篇
  1987年   966篇
  1986年   1041篇
  1985年   1052篇
  1984年   881篇
  1983年   801篇
  1982年   569篇
  1981年   560篇
  1979年   933篇
  1978年   665篇
  1975年   761篇
  1974年   818篇
  1973年   907篇
  1972年   766篇
  1971年   722篇
  1970年   643篇
  1969年   669篇
  1968年   852篇
  1967年   770篇
  1966年   650篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
42.
43.
44.
45.
46.
47.
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   
48.
This study examined the role of illness uncertainty in pain coping among women with fibromyalgia (FM), a chronic pain condition of unknown origin. Fifty-one FM participants completed initial demographic and illness uncertainty questionnaires and underwent 10-12 weekly interviews regarding pain, coping difficulty, and coping efficacy. Main outcome measures included weekly levels of difficulty coping with FM symptoms and coping efficacy. Multilevel analyses indicated that pain elevations for those high in illness uncertainty predicted increases in coping difficulty. Furthermore, when participants had more difficulty coping, they reported lower levels of coping efficacy. Results were consistent with hypothesized effects. Illness uncertainty accompanied by episodic pain negatively influenced coping efficacy, an important resource in adaptation to FM.  相似文献   
49.
This study evaluated cardiovascular responses (CVR) to an active speech task with blatantly discriminatory (BRC) versus neutral (NRC) stimuli and an anger recall task in a sample of Black men (N = 73; age 18 to 47). Diastolic blood pressure scores were higher for NRC versus BRC stimuli during anger recall (p = .05). Moreover, persons in the NRC group who perceived high levels of racism (vs. no racism or BRC group) during active speech showed larger increases in blood pressure across postspeech rest, anger recall, and subsequent rest (p = .03). The notable elevation in CVR in response to an ambiguous event extends current models of racism suggesting that subtle racism is a psychosocial stressor that erodes health through chronically elevated CVR.  相似文献   
50.
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