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   175446篇
  免费   954篇
  国内免费   4篇
耳鼻咽喉   1124篇
儿科学   6621篇
妇产科学   3009篇
基础医学   16513篇
口腔科学   1556篇
临床医学   12339篇
内科学   30806篇
皮肤病学   656篇
神经病学   16458篇
特种医学   8906篇
外科学   28900篇
综合类   2315篇
预防医学   18036篇
眼科学   2722篇
药学   9444篇
中国医学   625篇
肿瘤学   16374篇
  2021年   25篇
  2020年   24篇
  2019年   38篇
  2018年   21933篇
  2017年   17369篇
  2016年   19513篇
  2015年   906篇
  2014年   782篇
  2013年   754篇
  2012年   6945篇
  2011年   20959篇
  2010年   18809篇
  2009年   11497篇
  2008年   19459篇
  2007年   21662篇
  2006年   502篇
  2005年   2129篇
  2004年   3335篇
  2003年   4313篇
  2002年   2462篇
  2001年   307篇
  2000年   437篇
  1999年   179篇
  1998年   203篇
  1997年   200篇
  1996年   88篇
  1995年   98篇
  1994年   101篇
  1993年   65篇
  1992年   61篇
  1991年   100篇
  1990年   146篇
  1989年   109篇
  1988年   74篇
  1987年   64篇
  1986年   41篇
  1985年   46篇
  1984年   28篇
  1983年   28篇
  1982年   26篇
  1980年   39篇
  1974年   23篇
  1970年   24篇
  1969年   25篇
  1968年   24篇
  1938年   60篇
  1937年   25篇
  1934年   30篇
  1932年   56篇
  1930年   46篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
91.
Background. Accepted practices of informed consent often result in suboptimal patient understanding of research studies.Methods. This pilot study aimed to assess trial-specific tailored materials, compared to a widely used generic booklet about clinical trials, randomly assigned to 118 candidates for cancer clinical trials. Study outcomes were: satisfaction with decision-making; satisfaction with materials; and subjective understanding of the clinical trial.Results. There were no major differences between groups. Participants rated tailored materials higher as a useful reference.Conclusions. Trial-specific materials hold utility for reference during clinical trials. Studies of informed consent are feasible, although important factors limit research.  相似文献   
92.
The leaf essential oil of Eugenia zuchowskiae from Monteverde, Costa Rica, has been obtained by hydrodistillation and analyzed by GC–MS. The principal constituents of E. zuchowskiae leaf oil were α-pinene (28.3%), β-caryophyllene (13.2%), α-humulene (13.1%), and α-copaene (8.1%). The leaf essential oil of E. zuchowskiae showed pronounced in-vitro cytotoxic activity against MCF-7, MDA-MB-468, and UACC-257 human tumor cell lines. The major components showed cytotoxic activities comparable to doxorubicin (LC50 14–70 μg/ml).  相似文献   
93.
94.
95.
96.
The prevalence of primary headache (PH) in a multiple sclerosis (MS) sample vs. control healthy subjects was investigated at a neurological clinic in 2004–2005: 122 of 238 (51%) MS patients and 57 of 238 (23%) controls proved to be affected by headache. The groups did not differ for the rates of PH types. Headache types of MS patients were comparable to those of PH patients that were observed at the same institute in a case-control comparison. First symptoms of headache preceded those of MS in two thirds of cases. Headache features did not significantly change after MS onset. Comorbidity of MS and PH could be explained by some common clinical and biological traits.  相似文献   
97.
Single-agent chemotherapy of metastatic breast cancer is the treatment of choice in patients with slow tumor progression and asymptomatic disease. In this patient group, the choice of drugs is based more on good tolerability than on efficacy. By contrast, symptomatic or rapidly progressing disease requires the use of highly active regimens where more weight is put on reliable antitumor activity. While anthraycline-based combination regimens have set the standard of effective treatment, the addition of docetaxel (and to a lesser extent paclitaxel) has improved tumor response, but failed to induce a consistent prolongation of survival. Based on retrospective analyses, it is hypothesised that the combined use of anthracyclines and taxanes in first-line therapy may be most beneficial in defined subgroups: after adjuvant chemotherapy, in patients with HER-2 gene amplification, possibly also in patients with rapidly progressing visceral disease.  相似文献   
98.
99.
100.
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