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   102896篇
  免费   29585篇
  国内免费   1076篇
耳鼻咽喉   2456篇
儿科学   2872篇
妇产科学   2455篇
基础医学   3168篇
口腔科学   5076篇
临床医学   27009篇
内科学   25063篇
皮肤病学   3300篇
神经病学   12778篇
特种医学   3681篇
外科学   18214篇
综合类   247篇
现状与发展   40篇
一般理论   16篇
预防医学   14350篇
眼科学   2225篇
药学   1344篇
中国医学   13篇
肿瘤学   9250篇
  2024年   745篇
  2023年   5052篇
  2022年   1143篇
  2021年   2833篇
  2020年   5360篇
  2019年   2157篇
  2018年   7027篇
  2017年   7415篇
  2016年   7983篇
  2015年   8100篇
  2014年   10589篇
  2013年   12382篇
  2012年   4180篇
  2011年   3889篇
  2010年   7006篇
  2009年   9253篇
  2008年   3843篇
  2007年   2777篇
  2006年   3917篇
  2005年   2520篇
  2004年   1884篇
  2003年   1489篇
  2002年   1386篇
  2001年   1843篇
  2000年   1155篇
  1999年   1700篇
  1998年   2126篇
  1997年   1943篇
  1996年   1997篇
  1995年   1733篇
  1994年   1154篇
  1993年   955篇
  1992年   764篇
  1991年   650篇
  1990年   520篇
  1989年   526篇
  1988年   515篇
  1987年   384篇
  1986年   361篇
  1985年   298篇
  1984年   263篇
  1983年   311篇
  1982年   241篇
  1981年   215篇
  1980年   130篇
  1978年   131篇
  1977年   120篇
  1976年   95篇
  1974年   73篇
  1972年   72篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
63.
This column contains the presidential address presented during the Third Annual Meeting of the American Association of Heart Failure Nurses on June 28, 2007, in San Diego, California, titled "Building the Foundation of Excellence in Heart Failure Nursing."  相似文献   
64.
65.
PURPOSE: This study describes the prevalence of probable major depressive disorder (MDD) as well as other depressive disorders (ODD) and severity of depressive symptoms in a national sample of women with spinal cord injury (SCI) and compares them with a case-matched sample of men with SCI. METHODS: A sample of 585 women was drawn and case-matched with men from the SCI Model System National SCI Database according to level/completeness of injury, follow-up year, and age. The outcome measure of depression was the Patient Health Questionnaire. MAIN FINDINGS: Prevalence rates for women were 7.9% for probable MDD and 9.7% for ODD; rates for men were 9.9% and 10.3%, respectively. Logistic regression revealed that women who were divorced or at year 1 follow-up had a higher odds of having probable MDD (odds ratio [OR], 3.4 and 2.9, respectively). Employed women and men had significantly lower odds of probable MDD (OR, 0.274 and 0.358, respectively). Statistically significant differences were not found in gender comparisons for either probable MDD or symptom severity, which also were not associated with injury characteristics. CONCLUSION: The most significant, and unexpected, research finding is the absence of gender differences in probable MDD and symptom severity. Results challenge notions that depression will necessarily follow SCI; that injury characteristics determine the development and severity of depression; and that women experience a greater burden of depression than men. The main clinical implication is that depression screening and referral should be a routine feature of health care for women living with SCI, as well as for their male counterparts. Furthermore, nearly one fourth of women and men reported experiencing some or greater difficulty in daily life and relationships in the absence of probable depressive disorder, warranting monitoring of subsyndromal depression as well.  相似文献   
66.
67.
68.
Using an earlier model, which described the critical contact angle for binding from second-order angulation alone, a more generalized model is derived that combines the effects of angulation and torque. From this vantage point, the onset of binding is evaluated for 3 scenarios: second-order angulation alone, third-order torque only, and a combination of second-order angulation and third-order torque. These scenarios are detailed by plotting the critical contact angle for binding against the torque angle as a function of 10 wire dimensions (16 x 16, 16 x 22, 17 x 17, 17 x 22, 17 x 25, 18 x 18, 18 x 22, 18 x 25, 19 x 25, and 21 x 25 mil), 4 bracket widths (70, 100, 130, and 160 mil), and 4 bracket slots (18, 20.5, 22, and 24.5 mil). From these plots, we learn that each wire base dimension (eg, an 18-mil base as found in 18 x 18-mil, 18 x 22-mil and 18 x 25-mil archwires) has a common maximum critical contact angle for binding. Moreover, each wire-slot combination has a common maximum torque angle, which is independent of bracket width. Finally, we learn that archwire-bracket combinations that use a metric 0.5-mm slot might have some advantages with regard to torquing--given the current philosophy that light, continuous forces are more favorable.  相似文献   
69.
70.
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