全文获取类型
收费全文 | 1138744篇 |
免费 | 88571篇 |
国内免费 | 9827篇 |
专业分类
耳鼻咽喉 | 14591篇 |
儿科学 | 36488篇 |
妇产科学 | 31612篇 |
基础医学 | 163640篇 |
口腔科学 | 30753篇 |
临床医学 | 107491篇 |
内科学 | 217235篇 |
皮肤病学 | 24512篇 |
神经病学 | 87616篇 |
特种医学 | 43130篇 |
外国民族医学 | 353篇 |
外科学 | 166028篇 |
综合类 | 41499篇 |
现状与发展 | 24篇 |
一般理论 | 408篇 |
预防医学 | 86200篇 |
眼科学 | 26538篇 |
药学 | 85909篇 |
59篇 | |
中国医学 | 7427篇 |
肿瘤学 | 65629篇 |
出版年
2021年 | 12139篇 |
2019年 | 10902篇 |
2018年 | 14872篇 |
2017年 | 11731篇 |
2016年 | 12788篇 |
2015年 | 15607篇 |
2014年 | 20903篇 |
2013年 | 28082篇 |
2012年 | 37992篇 |
2011年 | 40516篇 |
2010年 | 24349篇 |
2009年 | 22152篇 |
2008年 | 35396篇 |
2007年 | 37402篇 |
2006年 | 37666篇 |
2005年 | 36426篇 |
2004年 | 33705篇 |
2003年 | 32198篇 |
2002年 | 30772篇 |
2001年 | 52693篇 |
2000年 | 53980篇 |
1999年 | 45856篇 |
1998年 | 13812篇 |
1997年 | 12364篇 |
1996年 | 11949篇 |
1995年 | 11327篇 |
1994年 | 10419篇 |
1993年 | 9439篇 |
1992年 | 34698篇 |
1991年 | 33577篇 |
1990年 | 32902篇 |
1989年 | 31636篇 |
1988年 | 28773篇 |
1987年 | 28747篇 |
1986年 | 26646篇 |
1985年 | 25621篇 |
1984年 | 19083篇 |
1983年 | 16042篇 |
1982年 | 9554篇 |
1979年 | 17204篇 |
1978年 | 12336篇 |
1977年 | 10408篇 |
1976年 | 9843篇 |
1975年 | 10260篇 |
1974年 | 12416篇 |
1973年 | 11950篇 |
1972年 | 10977篇 |
1971年 | 10201篇 |
1970年 | 9457篇 |
1969年 | 8810篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
22.
23.
24.
25.
M.F. Werner A. López-Rueda F.X. Zarco J. Blasco L. San Román S. Amaro E. Carrero R. Valero L. Oleaga J.M. Macho N. Bargalló 《Radiologia》2019,61(2):143-152
Purpose
Endovascular treatment with mechanical thrombectomy devices demonstrated high recanalization rates but functional outcome did not correlate with high rates of recanalization obtained. Patient selection prior to the endovascular treatment is very important in the final outcome of the patient. The primary aim of our study was to evaluate the prognostic value of posterior circulation Alberta Stroke Program Early CT Score (pc-ASPECTS) and Pons-Midbrain Index (PMI) scores in patients with Basilar Artery Occlusion (BAO) treated with successful angiographic recanalization after mechanical thrombectomy.Methods
Retrospective single-center study including 18 patients between 2008 and 2013 who had acute basilar artery occlusion managed with endovascular treatment within 24 hours from symptoms onset and with successful angiographic recanalization. The patients were initially classified into two groups according to clinical outcome and mortality at 90 days. For analysis we also divided patients into groups based on pc-ASPECTS (≥8vs.< 8) and PMI (≥3vs.< 3) on non-contrast CT (NCCT) and CT Angiography Source Images (CTASI). Imaging data were correlated to clinical outcome and mortality rate.Results
CTASI pc-ASPECTS, dichotomized at < 8 versus≥8, was associated with a favorable outcome (RR: 2.6; 95% CI: 1.3-5.2) and a reduced risk of death (RR: 6.5: 95% CI: 7.8-23.3). All patients that survived and were functionally independent had pc-ASPECTS score≥8. None of the 5 patients with CTASI pc-ASPECTS score less than 8 survived.Conclusion
PC-ASPECTS on CTASI is helpful for predicting functional outcome after BAO recanalization with endovascular treatment. These results should be validated in a randomized controlled trial in order to decide whether or not to treat a patient with BAO. 相似文献26.
ABSTRACTIn clinical trials, selection of appropriate study endpoints is critical for an accurate and reliable evaluation of safety and effectiveness of a test treatment under investigation. In practice, however, there are usually multiple endpoints available for measurement of disease status and/or therapeutic effect of the test treatment under study. For example, in cancer clinical trials, overall survival, response rate, and/or time to disease progression are usually considered as primary clinical endpoints for evaluation of safety and effectiveness of the test treatment under investigation. Once the study endpoints have been selected, sample size required for achieving a desired power is then determined. It, however, should be noted that different study endpoints may result in different sample sizes. In practice, it is usually not clear which study endpoint can best inform the disease status and measure the treatment effect. Moreover, different study endpoints may not translate one another although they may be highly correlated one another. In this article, we intend to develop an innovative endpoint namely therapeutic index based on a utility function to combine and utilize information collected from all study endpoints. Statistical properties and performances of the proposed therapeutic index are evaluated theoretically. A numerical example concerning a cancer clinical trial is given to illustrate the use of the proposed therapeutic index. 相似文献
27.
28.
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29.
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
30.
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