全文获取类型
| 收费全文 | 939945篇 |
| 免费 | 66732篇 |
| 国内免费 | 1352篇 |
专业分类
| 耳鼻咽喉 | 12997篇 |
| 儿科学 | 24724篇 |
| 妇产科学 | 23391篇 |
| 基础医学 | 133781篇 |
| 口腔科学 | 28865篇 |
| 临床医学 | 81249篇 |
| 内科学 | 184576篇 |
| 皮肤病学 | 19324篇 |
| 神经病学 | 72929篇 |
| 特种医学 | 37161篇 |
| 外国民族医学 | 81篇 |
| 外科学 | 153410篇 |
| 综合类 | 18131篇 |
| 现状与发展 | 1篇 |
| 一般理论 | 240篇 |
| 预防医学 | 62380篇 |
| 眼科学 | 21522篇 |
| 药学 | 73013篇 |
| 3篇 | |
| 中国医学 | 2164篇 |
| 肿瘤学 | 58087篇 |
出版年
| 2018年 | 9073篇 |
| 2017年 | 7116篇 |
| 2016年 | 7840篇 |
| 2015年 | 8943篇 |
| 2014年 | 12121篇 |
| 2013年 | 17721篇 |
| 2012年 | 24351篇 |
| 2011年 | 25360篇 |
| 2010年 | 14995篇 |
| 2009年 | 14453篇 |
| 2008年 | 24935篇 |
| 2007年 | 26026篇 |
| 2006年 | 26832篇 |
| 2005年 | 25758篇 |
| 2004年 | 24901篇 |
| 2003年 | 23881篇 |
| 2002年 | 23429篇 |
| 2001年 | 54953篇 |
| 2000年 | 56762篇 |
| 1999年 | 47138篇 |
| 1998年 | 10809篇 |
| 1997年 | 9541篇 |
| 1996年 | 9673篇 |
| 1995年 | 8995篇 |
| 1994年 | 8336篇 |
| 1993年 | 7650篇 |
| 1992年 | 35667篇 |
| 1991年 | 34086篇 |
| 1990年 | 32911篇 |
| 1989年 | 32074篇 |
| 1988年 | 29165篇 |
| 1987年 | 28438篇 |
| 1986年 | 26464篇 |
| 1985年 | 25302篇 |
| 1984年 | 17980篇 |
| 1983年 | 15231篇 |
| 1982年 | 7863篇 |
| 1981年 | 6833篇 |
| 1979年 | 15898篇 |
| 1978年 | 10692篇 |
| 1977年 | 9136篇 |
| 1976年 | 7965篇 |
| 1975年 | 8717篇 |
| 1974年 | 10561篇 |
| 1973年 | 9981篇 |
| 1972年 | 9453篇 |
| 1971年 | 8929篇 |
| 1970年 | 8499篇 |
| 1969年 | 7982篇 |
| 1968年 | 7267篇 |
排序方式： 共有10000条查询结果，搜索用时 15 毫秒
1.
2.
Stepanova E. S. Makarenkova L. M. Chistyakov V. V. Rybakov Yu. L. Gukasov V. M. Fedotcheva T. A. Parshin V. A. Votyakov V. A. Shimanovskii N. L. 《Pharmaceutical Chemistry Journal》2019,52(12):1016-1020
Pharmaceutical Chemistry Journal - An HPLC-MS method for simultaneous quantitative determination of a novel gestagenic pharmaceutical and two of its metabolites in rat and rabbit blood sera was... 相似文献
3.
Elizabeth D. Krebs Robert B. Hawkins J. Hunter Mehaffey Clifford E. Fonner Alan M. Speir Mohammed A. Quader Jeffrey B. Rich Leora T. Yarboro Nicholas R. Teman Gorav Ailawadi 《The Journal of thoracic and cardiovascular surgery》2019,157(4):1533-1542.e2
Objectives
Expedient extubation after cardiac surgery has been associated with improved outcomes, leading to postoperative extubation frequently during overnight hours. However, recent evidence in a mixed medical-surgical intensive care unit population demonstrated worse outcomes with overnight extubation. This study investigated the impact of overnight extubation in a statewide, multicenter Society of Thoracic Surgeons database.Methods
Records from 39,812 patients undergoing coronary artery bypass grafting or valve operations (2008-2016) and extubated within 24 hours were stratified according to extubation time between 06:00 and 18:00 (day) or between 18:00 and 6:00 (overnight). Outcomes including reintubation, mortality, and composite morbidity-mortality were evaluated using hierarchical regression models adjusted for Society of Thoracic Surgeons predictive risk scores. To further analyze extubation during the night, a subanalysis stratified patients into 3 groups: 06:00 to 18:00, 18:00 to 24:00, and 24:00 to 06:00.Results
A total of 20,758 patients were extubated overnight (52.1%) and were slightly older (median age 66 vs 65 years, P < .001) with a longer duration of ventilation (4 vs 7 hours, P < .001). Day and overnight extubation were associated with equivalent operative mortality (1.7% vs 1.7%, P = .880), reintubation (3.7% vs 3.4%, P = .141), and composite morbidity-mortality (8.2% vs 8.0%, P = .314). After risk adjustment, overnight extubation was not associated with any difference in reintubation, mortality, or composite morbidity-mortality. On subanalysis, those extubated between 24:00 and 06:00 exhibited increased composite morbidity-mortality (odds ratio, 1.18; P = .001) but no difference in reintubation or mortality.Conclusions
Extubation overnight was not associated with increased mortality or reintubation. These results suggest that in the appropriate clinical setting, it is safe to routinely extubate cardiac surgery patients overnight. 相似文献4.
5.
6.
7.
Well‐being,health and fitness of children who use wheelchairs: Feasibility study protocol to develop child‐centred ‘keep‐fit’ exercise interventions 
下载免费PDF全文
下载免费PDF全文 8.
9.
10.