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   161118篇
  免费   31255篇
  国内免费   2425篇
耳鼻咽喉   5310篇
儿科学   5547篇
妇产科学   2674篇
基础医学   5195篇
口腔科学   1724篇
临床医学   27110篇
内科学   48057篇
皮肤病学   7844篇
神经病学   15531篇
特种医学   7873篇
外科学   42303篇
综合类   307篇
现状与发展   72篇
预防医学   7756篇
眼科学   3427篇
药学   2013篇
中国医学   99篇
肿瘤学   11956篇
  2024年   693篇
  2023年   4823篇
  2022年   1237篇
  2021年   3182篇
  2020年   6081篇
  2019年   2216篇
  2018年   7563篇
  2017年   7451篇
  2016年   8573篇
  2015年   8503篇
  2014年   15667篇
  2013年   15944篇
  2012年   6141篇
  2011年   6457篇
  2010年   10772篇
  2009年   14354篇
  2008年   6496篇
  2007年   4863篇
  2006年   7296篇
  2005年   4421篇
  2004年   3620篇
  2003年   2602篇
  2002年   2595篇
  2001年   4159篇
  2000年   3476篇
  1999年   3468篇
  1998年   3708篇
  1997年   3508篇
  1996年   3390篇
  1995年   3253篇
  1994年   1960篇
  1993年   1581篇
  1992年   1393篇
  1991年   1427篇
  1990年   1083篇
  1989年   1195篇
  1988年   1040篇
  1987年   864篇
  1986年   907篇
  1985年   744篇
  1984年   566篇
  1983年   541篇
  1982年   539篇
  1981年   427篇
  1980年   389篇
  1979年   334篇
  1978年   360篇
  1977年   411篇
  1975年   304篇
  1972年   316篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
32.
Marielle Kabbouche MD  FAHS 《Headache》2015,55(10):1426-1429
Status migrainosus is defined by the international classification of headache disorders (ICHD) criteria as a debilitating migraine lasting more then 72 hours. The epidemiology of status migrainosus is still unknown in adult and children, and frequently underdiagnosed. Children and adolescents often end up in the emergency room with an intractable headache that failed outpatient therapy. Six to seven percent of these children do not respond to acute infusion therapy and require hospitalization. It is imperative that more aggressive therapy is considered when patients are affected by a severe intractable headache to prevent further disability and returning the child to baseline activity. Multiple therapies are available for adults and children. Studies for acute therapy in the emergency room are available in adults and pediatric groups. Small studies are available for inpatient therapy in children and, along with available therapies for children and adolescents, are described in this review. A review of the literature shows growing evidence regarding the use of dihydroergotamine intravenously once patients are hospitalized. Effectiveness and safety have been proven in the last decades in adults and small studies in the pediatric populations.  相似文献   
33.
34.
Metabolomics may reveal novel insights into the etiology of prostate cancer, for which few risk factors are established. We investigated the association between patterns in baseline plasma metabolite profile and subsequent prostate cancer risk, using data from 3,057 matched case–control sets from the European Prospective Investigation into Cancer and Nutrition (EPIC). We measured 119 metabolite concentrations in plasma samples, collected on average 9.4 years before diagnosis, by mass spectrometry (AbsoluteIDQ p180 Kit, Biocrates Life Sciences AG). Metabolite patterns were identified using treelet transform, a statistical method for identification of groups of correlated metabolites. Associations of metabolite patterns with prostate cancer risk (OR1SD) were estimated by conditional logistic regression. Supplementary analyses were conducted for metabolite patterns derived using principal component analysis and for individual metabolites. Men with metabolite profiles characterized by higher concentrations of either phosphatidylcholines or hydroxysphingomyelins (OR1SD = 0.77, 95% confidence interval 0.66–0.89), acylcarnitines C18:1 and C18:2, glutamate, ornithine and taurine (OR1SD = 0.72, 0.57–0.90), or lysophosphatidylcholines (OR1SD = 0.81, 0.69–0.95) had lower risk of advanced stage prostate cancer at diagnosis, with no evidence of heterogeneity by follow-up time. Similar associations were observed for the two former patterns with aggressive disease risk (the more aggressive subset of advanced stage), while the latter pattern was inversely related to risk of prostate cancer death (OR1SD = 0.77, 0.61–0.96). No associations were observed for prostate cancer overall or less aggressive tumor subtypes. In conclusion, metabolite patterns may be related to lower risk of more aggressive prostate tumors and prostate cancer death, and might be relevant to etiology of advanced stage prostate cancer.  相似文献   
35.
36.
37.
Gorlin syndrome (naevoid basal cell carcinoma syndrome) is a genetically linked disorder characterized by the development of multiple basal cell carcinomas (BCCs) throughout life. Cumulative surgery, cryotherapy and other conventional interventions can result in significant disfigurement by middle age. Radiotherapy is contra-indicated because the mutated gene underlying the syndrome, ‘PTCH’, increases sensitivity to ionising radiation, so there is significant likelihood of inducing further tumours in and around the irradiated area. Photodynamic therapy offers a non-invasive treatment option for patients with this condition, with the added advantage of causing minimal scarring.  相似文献   
38.
39.
40.
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