全文获取类型
| 收费全文 | 1596766篇 |
| 免费 | 118426篇 |
| 国内免费 | 3629篇 |
学科分类
| 医药卫生 | 1718821篇 |
出版年
| 2018年 | 17183篇 |
| 2017年 | 13360篇 |
| 2016年 | 15055篇 |
| 2015年 | 16890篇 |
| 2014年 | 23060篇 |
| 2013年 | 35103篇 |
| 2012年 | 46362篇 |
| 2011年 | 49148篇 |
| 2010年 | 29314篇 |
| 2009年 | 27598篇 |
| 2008年 | 45825篇 |
| 2007年 | 48939篇 |
| 2006年 | 49629篇 |
| 2005年 | 47176篇 |
| 2004年 | 46058篇 |
| 2003年 | 44160篇 |
| 2002年 | 42767篇 |
| 2001年 | 77097篇 |
| 2000年 | 79003篇 |
| 1999年 | 65678篇 |
| 1998年 | 17986篇 |
| 1997年 | 15735篇 |
| 1996年 | 16062篇 |
| 1995年 | 15302篇 |
| 1994年 | 14154篇 |
| 1993年 | 13184篇 |
| 1992年 | 51677篇 |
| 1991年 | 50749篇 |
| 1990年 | 49777篇 |
| 1989年 | 48610篇 |
| 1988年 | 44256篇 |
| 1987年 | 43802篇 |
| 1986年 | 41147篇 |
| 1985年 | 39489篇 |
| 1984年 | 29274篇 |
| 1983年 | 24733篇 |
| 1982年 | 14356篇 |
| 1981年 | 12826篇 |
| 1979年 | 26786篇 |
| 1978年 | 19181篇 |
| 1977年 | 16128篇 |
| 1976年 | 15402篇 |
| 1975年 | 16487篇 |
| 1974年 | 19709篇 |
| 1973年 | 18942篇 |
| 1972年 | 17631篇 |
| 1971年 | 16328篇 |
| 1970年 | 15443篇 |
| 1969年 | 14326篇 |
| 1968年 | 13233篇 |
排序方式： 共有10000条查询结果，搜索用时 375 毫秒
31.
Novozhilov A. V. Mindukshev I. V. Korf E. A. Krivchenko A. I. Goncharov N. V. 《Bulletin of experimental biology and medicine》2020,168(4):444-448
Bulletin of Experimental Biology and Medicine - Ammonium, an end-product of catabolism, in low doses can promote adaptation of metabolic pathways in erythrocytes under conditions of extreme... 相似文献
32.
33.
Alexandra B. Morshed Rachel G. Tabak Cynthia D. Schwarz Debra Haire-Joshu 《Journal of nutrition education and behavior》2019,51(2):237-244
Objective
To examine whether a healthy weight intervention embedded in the Parents as Teachers (PAT) home visiting program, which was previously found to improve mothers’ body mass index (BMI) and obesity-related behaviors, changed the BMI of preschool children or maternal feeding practices.Methods
This stratified randomized trial included preschool-aged children at risk for overweight whose mothers were overweight or had obesity (n?=?179). The Healthy Eating and Active Living Taught at Home (HEALTH) intervention was based on the Diabetes Prevention Program. Differences were examined using repeated-measures mixed-ANOVA models.Results
Compared with PAT usual care, the HEALTH intervention had no effect on children's BMI or maternal feeding practices. However, combined analyses showed that children's BMI percentile decreased (P??=?.007), BMI z-scores were maintained (P??=?.19), and 3 of 8 feeding practices improved over time (P < .05).Conclusions and Implications
Additional research is needed to assess the effectiveness of PAT to prevent preschool-age obesity using rigorous designs (eg, group-randomized trials) and to identify its active components. HEALTH is ready to be scaled up to prevent maternal weight gain through embedding within the national PAT program. 相似文献34.
Martin R. Späth Malte P. Bartram Nicolàs Palacio-Escat K. Johanna R. Hoyer Cedric Debes Fatih Demir Christina B. Schroeter Amrei M. Mandel Franziska Grundmann Giuliano Ciarimboli Andreas Beyer Jayachandran N. Kizhakkedathu Susanne Brodesser Heike Göbel Jan U. Becker Thomas Benzing Bernhard Schermer Martin Höhne Markus M. Rinschen 《Kidney international》2019,95(2):333-349
35.
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36.
37.
38.
39.
B Maybury A Powell-Chandler N Kumar 《Annals of the Royal College of Surgeons of England》2015,97(3):e37-e38
We report two British cases of liver abscess, due to Klebsiella pneumoniae and associated with synchronous infection elsewhere, which required liver resection for definitive treatment. They illustrate the geographic spread of aggressive K pneumoniae liver infection and demonstrate the importance of early aggressive treatment. 相似文献
40.
Alina Goldenberg B.A. Catalina Matiz M.D. Lawrence F. Eichenfield M.D. 《Pediatric dermatology》2015,32(4):e191-e192
Henna, derived from a combination of natural leaves and coloring additives, is a common decorative dye traditionally used in many Islamic religious celebrations. Para‐phenylenediamine (PPD), a major component of black henna tattoo, is a strong sensitizer and common allergen. We report a case of severe connubial allergic contact dermatitis after black henna heterotransfer in a girl. 相似文献
