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   939105篇
  免费   66035篇
  国内免费   2453篇
耳鼻咽喉   13045篇
儿科学   29841篇
妇产科学   26898篇
基础医学   131994篇
口腔科学   25579篇
临床医学   79191篇
内科学   191131篇
皮肤病学   19403篇
神经病学   74961篇
特种医学   37983篇
外国民族医学   336篇
外科学   147634篇
综合类   19825篇
一般理论   276篇
预防医学   68760篇
眼科学   21171篇
药学   66480篇
中国医学   1837篇
肿瘤学   51248篇
  2018年   9574篇
  2017年   7610篇
  2016年   8152篇
  2015年   9344篇
  2014年   13273篇
  2013年   20767篇
  2012年   27686篇
  2011年   29518篇
  2010年   17787篇
  2009年   16941篇
  2008年   28154篇
  2007年   30108篇
  2006年   30261篇
  2005年   29807篇
  2004年   28506篇
  2003年   27690篇
  2002年   27285篇
  2001年   42017篇
  2000年   43189篇
  1999年   36955篇
  1998年   10500篇
  1997年   9635篇
  1996年   9518篇
  1995年   8866篇
  1994年   8484篇
  1993年   7943篇
  1992年   28715篇
  1991年   27452篇
  1990年   26867篇
  1989年   25824篇
  1988年   23986篇
  1987年   23600篇
  1986年   22666篇
  1985年   21595篇
  1984年   16242篇
  1983年   13903篇
  1982年   8600篇
  1981年   7522篇
  1979年   14964篇
  1978年   10537篇
  1977年   8948篇
  1976年   8394篇
  1975年   9206篇
  1974年   10981篇
  1973年   10459篇
  1972年   9900篇
  1971年   9095篇
  1970年   8707篇
  1969年   8141篇
  1968年   7796篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
71.

The Centers for Disease Control and Prevention (CDC) and 35 partner organizations have engaged in developing an agenda for Preconception Health. A summit was held in June 2005 to discuss the current state of knowledge regarding preconception care and convene a select panel to develop recommendations and action steps for improving the health of women, children, and families through advances in clinical care, public health, and community action. A Select Panel on Preconception Care, convened by CDC, deliberated critical related issues and created refined definition of preconception care. The panel also developed a strategic plan with goals, recommendations, and action steps for improving preconception health. The recommendations and action steps are specific to the implementation of health behavior, access, consumer demand, research, and surveillance activities for monitoring and improving the health of women, children and families. The outcome of the deliberations is the CDC publication of detailed recommendations and action steps in the Morbidity and Mortality Weekly Report series, Recommendations and Reports.

  相似文献   
72.
73.
74.
75.
OBJECTIVE: To assess whether pharmacokinetic drug interactions occur when sertraline is added to antipsychotic medications. METHOD: Forty-eight patients with remitted DSM-IV schizophrenia and comorbid major depression were randomized to placebo for 6 weeks or sertraline 50 mg for 4 weeks followed by sertraline 50 mg to 100 mg for 2 weeks for nonresponders. Treatment with the patients' usual antipsychotic continued. Weekly clinical outcome assessments occurred for 6 weeks, and serum samples for drug monitoring were collected at Weeks 1, 5, and 6. Serum concentrations of sertraline and antipsychotics were measured with standard assays. RESULTS: In both placebo- and sertraline-treated groups, most patients displayed minor fluctuations in antipsychotic serum levels over 6 weeks. There was no clinical evidence of drug interactions in the sertraline-treated group. CONCLUSIONS: Clinically significant adverse effects did not occur despite variable antipsychotic serum levels with or without sertraline. Concern about pharmacokinetic interactions should not deter the use of sertraline for depression in individuals with schizophrenia.  相似文献   
76.
77.
78.
Our group have studied a patient affected by a malignant schwannoma in the posterior tibial nerve. Schwannomas are uncommon neoplasms that originate from the Schwann cells of the peripheral nerves: the most common forms are benign. Malignant transformation is rarer. The therapy is surgical and the operation undertaken, if possible, should be the amputation. Alternatively, where amputation is not possible due to the specific localisation or due to patient refusal, the alternative must be the largest and most radical excision possible.  相似文献   
79.
To examine the prevalence of Internet sex networking among men who have sex with men (MSM) in Hong Kong and risk behaviors associated with the behavior, a telephone survey of 15,230 Hong Kong Chinese men aged 18-60 was conducted. Of the 283 active MSM (having engaged in some MSM behaviors in the last 6 months) identified, 17.7% had networked for MSM partners via the Internet in the last 6 months. Younger age (odds ratio [OR] for age < or = 25 vs. age >25 = 4.67, 95% confidence interval [CI] = 2.35-9.28) and being an anal-sex MSM (OR = 4.72, 95% CI=2.36-9.44) were independent predictors of Internet sex networking. Being an Internet sex networker was associated with some risk behaviors such as having contracted a sexually transmitted disease (adjusted OR = 4.79, 95% CI = 1.34-17.11), having had > or = 3 MSM partners (adjusted OR = 4.74, 95% CI = 2.20-10.23), and having engaged in anal sex (adjusted OR = 3.95, 95% CI = 1.89-8.23). HIV prevention programs for MSM should thereby include Internet-based interventions.  相似文献   
80.
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