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   1551625篇
  免费   121263篇
  国内免费   3617篇
耳鼻咽喉   21089篇
儿科学   52153篇
妇产科学   45053篇
基础医学   220683篇
口腔科学   42168篇
临床医学   136724篇
内科学   308594篇
皮肤病学   37409篇
神经病学   129772篇
特种医学   61700篇
外国民族医学   488篇
外科学   234418篇
综合类   33676篇
现状与发展   3篇
一般理论   517篇
预防医学   116530篇
眼科学   35566篇
药学   109073篇
  1篇
中国医学   3587篇
肿瘤学   87301篇
  2021年   10929篇
  2019年   12850篇
  2018年   19183篇
  2017年   14794篇
  2016年   17197篇
  2015年   19236篇
  2014年   25950篇
  2013年   38273篇
  2012年   52919篇
  2011年   54994篇
  2010年   32306篇
  2009年   30360篇
  2008年   51259篇
  2007年   54504篇
  2006年   55089篇
  2005年   53905篇
  2004年   51382篇
  2003年   49265篇
  2002年   47606篇
  2001年   77527篇
  2000年   79106篇
  1999年   65392篇
  1998年   17342篇
  1997年   15478篇
  1996年   15370篇
  1995年   15372篇
  1994年   13997篇
  1993年   13103篇
  1992年   47724篇
  1991年   45352篇
  1990年   43394篇
  1989年   41303篇
  1988年   37763篇
  1987年   36967篇
  1986年   34345篇
  1985年   32735篇
  1984年   24942篇
  1983年   20929篇
  1982年   12807篇
  1981年   11335篇
  1979年   21955篇
  1978年   15514篇
  1977年   12849篇
  1976年   11981篇
  1975年   12577篇
  1974年   14996篇
  1973年   14480篇
  1972年   13593篇
  1971年   12400篇
  1970年   11726篇
排序方式: 共有10000条查询结果,搜索用时 93 毫秒
1.
2.
3.
4.
The Earth’s mean surface temperature is already approximately 1.1°C higher than pre-industrial levels. Exceeding a mean 1.5°C rise by 2050 will make global adaptation to the consequences of climate change less possible. To protect public health, anaesthesia providers need to reduce the contribution their practice makes to global warming. We convened a Working Group of 45 anaesthesia providers with a recognised interest in sustainability, and used a three-stage modified Delphi consensus process to agree on principles of environmentally sustainable anaesthesia that are achievable worldwide. The Working Group agreed on the following three important underlying statements: patient safety should not be compromised by sustainable anaesthetic practices; high-, middle- and low-income countries should support each other appropriately in delivering sustainable healthcare (including anaesthesia); and healthcare systems should be mandated to reduce their contribution to global warming. We set out seven fundamental principles to guide anaesthesia providers in the move to environmentally sustainable practice, including: choice of medications and equipment; minimising waste and overuse of resources; and addressing environmental sustainability in anaesthetists’ education, research, quality improvement and local healthcare leadership activities. These changes are achievable with minimal material resource and financial investment, and should undergo re-evaluation and updates as better evidence is published. This paper discusses each principle individually, and directs readers towards further important references.  相似文献   
5.
6.
7.
8.
Patients admitted to intensive care after cardiac arrest are at risk of circulatory shock and early mortality due to cardiovascular failure. The aim of this study was to evaluate the ability of the veno-arterial pCO2 difference (∆pCO2; central venous CO2 – arterial CO2) and lactate to predict early mortality in postcardiac arrest patients. This was a pre-planned prospective observational sub-study of the target temperature management 2 trial. The sub-study patients were included at five Swedish sites. Repeated measurements of ∆pCO2 and lactate were conducted at 4, 8, 12, 16, 24, 48, and 72 h after randomization. We assessed the association between each marker and 96-h mortality and their prognostic value for 96-h mortality. One hundred sixty-three patients were included in the analysis. Mortality at 96 h was 17%. During the initial 24 h, there was no difference in ∆pCO2 levels between 96-h survivors and non-survivors. ∆pCO2 measured at 4 h was associated with an increased risk of death within 96 h (adjusted odds ratio: 1.15; 95% confidence interval [CI]: 1.02–1.29; p = .018). Lactate levels were associated with poor outcome over multiple measurements. The area under the receiving operating curve to predict death within 96 h was 0.59 (95% CI: 0.48–0.74) and 0.82 (95% CI: 0.72–0.92) for ∆pCO2 and lactate, respectively. Our results do not support the use of ∆pCO2 to identify patients with early mortality in the postresuscitation phase. In contrast, non-survivors demonstrated higher lactate levels in the initial phase and lactate identified patients with early mortality with moderate accuracy.  相似文献   
9.
10.
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