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   82340篇
  免费   3267篇
  国内免费   45篇
  2020年   927篇
  2019年   1182篇
  2018年   1638篇
  2017年   1698篇
  2016年   1737篇
  2015年   1203篇
  2014年   1477篇
  2013年   6983篇
  2012年   2613篇
  2011年   2755篇
  2010年   1715篇
  2009年   1678篇
  2008年   2523篇
  2007年   2526篇
  2006年   2215篇
  2005年   2017篇
  2004年   1939篇
  2003年   1778篇
  2002年   1832篇
  2001年   2572篇
  2000年   2450篇
  1999年   1894篇
  1998年   966篇
  1997年   872篇
  1996年   798篇
  1995年   791篇
  1994年   778篇
  1993年   790篇
  1992年   1579篇
  1991年   1446篇
  1990年   1485篇
  1989年   1307篇
  1988年   1301篇
  1987年   1254篇
  1986年   1271篇
  1985年   1293篇
  1984年   1098篇
  1983年   978篇
  1982年   767篇
  1979年   1136篇
  1978年   836篇
  1975年   975篇
  1974年   1032篇
  1973年   1053篇
  1972年   881篇
  1971年   805篇
  1969年   786篇
  1968年   950篇
  1967年   909篇
  1966年   789篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
51.
52.
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   
53.
The authors used recursive partitioning methods to identify combinations of baseline characteristics that predict 2-year physical activity success in each of 3 physical activity interventions delivered in the multisite Activity Counseling Trial. The sample consisted of 874 initially sedentary primary care patients, ages 35-75 years, who were at risk for cardiovascular disease. Predictors of 2-year success were specific to each intervention and represented a range of domains, including physiological, demographic, psychosocial, health-related, and environmental variables. The results indicate how specific patient subgroups (e.g., obese, unfit individuals; high-income individuals in stable health) may respond differently to varying levels and amounts of professional assistance and support. The methods used provide a practical first step toward identifying clinically meaningful patient subgroups for further systematic investigation.  相似文献   
54.
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   
55.
56.
57.
58.
59.
60.
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