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   13245篇
  免费   993篇
  国内免费   53篇
耳鼻咽喉   168篇
儿科学   495篇
妇产科学   374篇
基础医学   1716篇
口腔科学   168篇
临床医学   1630篇
内科学   2556篇
皮肤病学   174篇
神经病学   1332篇
特种医学   320篇
外科学   1574篇
综合类   154篇
一般理论   22篇
预防医学   1233篇
眼科学   300篇
药学   936篇
中国医学   18篇
肿瘤学   1121篇
  2023年   120篇
  2022年   223篇
  2021年   431篇
  2020年   307篇
  2019年   377篇
  2018年   426篇
  2017年   354篇
  2016年   384篇
  2015年   396篇
  2014年   519篇
  2013年   720篇
  2012年   1059篇
  2011年   960篇
  2010年   588篇
  2009年   458篇
  2008年   800篇
  2007年   831篇
  2006年   757篇
  2005年   713篇
  2004年   689篇
  2003年   637篇
  2002年   588篇
  2001年   160篇
  2000年   129篇
  1999年   163篇
  1998年   122篇
  1997年   87篇
  1996年   74篇
  1995年   73篇
  1994年   42篇
  1993年   46篇
  1992年   80篇
  1991年   68篇
  1990年   64篇
  1989年   73篇
  1988年   59篇
  1987年   55篇
  1986年   53篇
  1985年   64篇
  1984年   45篇
  1983年   40篇
  1982年   38篇
  1981年   31篇
  1980年   26篇
  1979年   48篇
  1978年   31篇
  1977年   26篇
  1976年   26篇
  1973年   26篇
  1972年   26篇
排序方式: 共有10000条查询结果,搜索用时 109 毫秒
1.
Lessons Learned
  • The combination of trametinib and sorafenib has an acceptable safety profile, albeit at doses lower than approved for monotherapy.
  • Maximum tolerated dose is trametinib 1.5 mg daily and sorafenib 200 mg twice daily.
  • The limited anticancer activity observed in this unselected patient population does not support further exploration of trametinib plus sorafenib in patients with hepatocellular carcinoma.
BackgroundThe RAS/RAF/MEK/ERK signaling pathway is associated with proliferation and progression of hepatocellular carcinoma (HCC). Preclinical data suggest that paradoxical activation of the MAPK pathway may be one of the resistance mechanisms of sorafenib; therefore, we evaluated trametinib plus sorafenib in HCC.MethodsThis was a phase I study with a 3+3 design in patients with treatment‐naïve advanced HCC. The primary objective was safety and tolerability. The secondary objective was clinical efficacy.ResultsA total of 17 patients were treated with three different doses of trametinib and sorafenib. Two patients experienced dose‐limiting toxicity, including grade 4 hypertension and grade 3 elevation of aspartate aminotransferase (AST)/alanine aminotransferase (ALT)/bilirubin over 7 days. Maximum tolerated dose was trametinib 1.5 mg daily and sorafenib 200 mg twice a day. The most common grade 3/4 treatment‐related adverse events were elevated AST (37%) and hypertension (24%). Among 11 evaluable patients, 7 (63.6%) had stable disease with no objective response. The median progression‐free survival (PFS) and overall survival (OS) were 3.7 and 7.8 months, respectively. Phosphorylated‐ERK was evaluated as a pharmacodynamic marker, and sorafenib plus trametinib inhibited phosphorylated‐ERK up to 98.1% (median: 81.2%) in peripheral blood mononuclear cells.ConclusionTrametinib and sorafenib can be safely administered up to trametinib 1.5 mg daily and sorafenib 200 mg twice a day with limited anticancer activity in advanced HCC.  相似文献   
2.
3.
4.
Sex chromosome trisomies (SCT) are among the most common chromosomal duplications in humans. Due to recent technological advances in non-invasive screening, SCT can already be detected during pregnancy. This calls for more knowledge about the development of (young) children with SCT. This review focused on neurocognitive functioning of children with SCT between 0 and 18 years, on domains of global intellectual functioning, language, executive functioning, and social cognition, in order to identify targets that could benefit from early treatment. Online databases were used to identify peer-reviewed scientific articles using specific search terms. In total 18 studies were included. When applicable, effect sizes were calculated to indicate clinical significance. Results of the reviewed studies show that although traditionally, the focus has been on language and intelligence (IQ) in this population, recent studies suggest that executive functioning and social cognition may also be significantly affected already in childhood. These findings suggest that neuropsychological screening of children diagnosed with SCT should be extended, to also include executive functioning and social cognition. Knowledge about these neurocognitive risks is important to improve clinical care and help identify targets for early support and intervention programs to accommodate for the needs of individuals with SCT.  相似文献   
5.
6.
Purpose: Non-ambulatory persons with cerebral palsy are prone to low bone mineral density. In ambulatory persons with cerebral palsy, bone mineral density deficits are expected to be small or absent, but a consensus conclusion is lacking. In this systematic review bone mineral density in ambulatory persons with cerebral palsy (Gross Motor Function Classification Scales I–III) was studied.

Materials and methods: Medline, Embase, and Web of Science were searched. According to international guidelines, low bone mineral density was defined as Z-score?≤??2.0. In addition, we focused on Z-score?≤??1.0 because this may indicate a tendency towards low bone mineral density.

Results: We included 16 studies, comprising 465 patients aged 1–65?years. Moderate and conflicting evidence for low bone mineral density (Z-score?≤??2.0) was found for several body parts (total proximal femur, total body, distal femur, lumbar spine) in children with Gross Motor Function Classification Scales II and III. We found no evidence for low bone mineral density in children with Gross Motor Function Classification Scale I or adults, although there was a tendency towards low bone mineral density (Z-score?≤??1.0) for several body parts.

Conclusions: Although more high-quality research is needed, results indicate that deficits in bone mineral density are not restricted to non-ambulatory people with cerebral palsy.

  • Implications for Rehabilitation
  • Although more high-quality research is needed, including adults and fracture risk assessment, the current study indicates that deficits in bone mineral density are not restricted to non-ambulatory people with CP.

  • Health care professionals should be aware that optimal nutrition, supplements on indication, and an active lifestyle, preferably with weight-bearing activities, are important in ambulatory people with CP, also from a bone quality point-of-view.

  • If indicated, medication and fall prevention training should be prescribed.

  相似文献   
7.
8.

Background

Physicians treating nonvalvular atrial fibrillation (AF) assess stroke and bleeding risks when deciding on anticoagulation. The agreement between empirical and physician-estimated risks is unclear. Furthermore, the association between patient and physician sex and anticoagulation decision-making is uncertain.

Methods

We pooled data from 2 national primary care physician chart audit databases of patients with AF (Facilitating Review and Education to Optimize Stroke Prevention in Atrial Fibrillation and Coordinated National Network to Engage Physicians in the Care and Treatment of Patients with Atrial Fibrillation Chart Audit) with a combined 1035 physicians (133 female, 902 male) and 10,927 patients (4567 female and 6360 male).

Results

Male physicians underestimated stroke risk in female patients and overestimated risk in male patients. Female physicians estimated stroke risk well in female patients but underestimated the risk in male patients. Risk of bleeding was underestimated in all. Despite differences in risk assessment by physician and patient sex, > 90% of patients received anticoagulation across all subgroups. There was modest agreement between physician estimated and calculated (ie, CHADS2 score) stroke risk: Kappa scores were 0.41 (0.35-0.47) for female physicians and 0.34 (0.32-0.36) for male physicians.

Conclusions

Our study is the first to examine the association between patient and physician sex influences and stroke and bleeding risk estimation in AF. Although there were differences in agreement between physician estimated stroke risk and calculated CHADS2 scores, these differences were small and unlikely to affect clinical practice; further, despite any perceived differences in the accuracy of risk assessment by sex, most patients received anticoagulation.  相似文献   
9.
10.
Healthcare workers (HCWs) are at increased risk of both exposure and transmission of infectious disease. Two European Union (EU) directives state that health services are responsible for assessing their employees’ potential exposure to infectious diseases and offering immunisation free of charge. We assessed current policy for immunisation of HCWs and the availability of vaccine coverage data in the Nordic countries by surveying national vaccination experts in Denmark, Finland, Iceland, Norway and Sweden, as well as Swedish county medical officers (CMOs). All national experts and 17 of 21 Swedish CMOs responded. All EU countries had transposed the European directives into national law, while Norway and Iceland had similar national legislation. Recommendations or guidelines were issued in Denmark, Finland, Iceland, Norway and 15 of 17 responding Swedish counties. The range of diseases covered differed by countries and Swedish counties. HCW vaccine coverage data were not systematically collected; incomplete estimates were only available for Finland and two Swedish counties. In conclusion, recommendations or guidelines exist in the Nordic countries, but their impact cannot be assessed, as vaccine uptake among HCWs is not currently measured. Systematic collection of data is a necessary step towards improving HCW immunisation policy and practice in the Nordic countries.  相似文献   
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