全文获取类型
收费全文 | 199012篇 |
免费 | 2368篇 |
国内免费 | 205篇 |
专业分类
耳鼻咽喉 | 1295篇 |
儿科学 | 7973篇 |
妇产科学 | 3358篇 |
基础医学 | 19395篇 |
口腔科学 | 1936篇 |
临床医学 | 13838篇 |
内科学 | 34990篇 |
皮肤病学 | 1107篇 |
神经病学 | 18018篇 |
特种医学 | 9654篇 |
外国民族医学 | 5篇 |
外科学 | 32002篇 |
综合类 | 3221篇 |
一般理论 | 2篇 |
预防医学 | 19686篇 |
眼科学 | 3976篇 |
药学 | 11913篇 |
5篇 | |
中国医学 | 1007篇 |
肿瘤学 | 18204篇 |
出版年
2023年 | 153篇 |
2022年 | 362篇 |
2021年 | 613篇 |
2020年 | 365篇 |
2019年 | 442篇 |
2018年 | 22348篇 |
2017年 | 17695篇 |
2016年 | 19916篇 |
2015年 | 1436篇 |
2014年 | 1567篇 |
2013年 | 1792篇 |
2012年 | 8348篇 |
2011年 | 22369篇 |
2010年 | 19591篇 |
2009年 | 12146篇 |
2008年 | 20585篇 |
2007年 | 22768篇 |
2006年 | 1571篇 |
2005年 | 3155篇 |
2004年 | 4220篇 |
2003年 | 5180篇 |
2002年 | 3289篇 |
2001年 | 948篇 |
2000年 | 1104篇 |
1999年 | 796篇 |
1998年 | 484篇 |
1997年 | 441篇 |
1996年 | 312篇 |
1995年 | 303篇 |
1994年 | 248篇 |
1993年 | 233篇 |
1992年 | 432篇 |
1991年 | 521篇 |
1990年 | 522篇 |
1989年 | 504篇 |
1988年 | 377篇 |
1987年 | 383篇 |
1986年 | 287篇 |
1985年 | 341篇 |
1984年 | 280篇 |
1983年 | 253篇 |
1982年 | 175篇 |
1980年 | 161篇 |
1979年 | 208篇 |
1978年 | 154篇 |
1975年 | 152篇 |
1974年 | 177篇 |
1973年 | 159篇 |
1972年 | 137篇 |
1971年 | 159篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
21.
23.
24.
Parupudi V J Sriram Guduru V Rao Nageshwar D Reddy 《Indian journal of gastroenterology》2006,25(1):39-41
Endoscopic clips have been used mainly for control of gastrointestinal (GI) bleeding and occasionally for closure of GI perforations. However, closure of spontaneous esophageal perforation (Boerhaave's syndrome) by clipping has not been reported. We described successful non-surgical closure of spontaneous esophageal perforation by endoscopic clipping in a patient with bilateral pyopneumothorax and septicemia. 相似文献
25.
Melissa Terpstra Ivan Tkác Raghavendra Rao Rolf Gruetter 《Magnetic resonance in medicine》2006,55(5):979-983
Both ultrashort echo-time STEAM and MEGA-PRESS-edited spectroscopy were used to validate noninvasive quantification of vitamin C (ascorbate) in the developing rat brain, where changes in ascorbate concentration have been reported. Despite strong overlap with resonances from glutamine, glutamate, glutathione, and macromolecules, reliable quantification of ascorbate (Cramer-Rao lower bounds<0.2 micromol/g) by LCModel analysis of STEAM (TE=2 ms) spectra was possible at 9.4 T. Ascorbate concentrations quantified from the STEAM spectra were in very good agreement with concentrations calculated from fully resolved ascorbate resonances in MEGA-PRESS-edited spectra measured from identical volumes of interest. Ascorbate concentrations measured using STEAM decreased with increasing postnatal rat age, in agreement with published brain ascorbate concentrations measured in vitro using high-performance liquid chromatography (HPLC). 相似文献
26.
27.
28.
Prevalence of vitamin D depletion among morbidly obese patients seeking gastric bypass surgery 总被引:5,自引:0,他引:5
Arthur M. Carlin M.D. D. Sudhaker Rao MB B.S. F.A.C.P. F.A.C.E. Ali M. Meslemani M.D. Jeffrey A. Genaw M.D. Nayana J. Parikh Shiri Levy M.D. Arti Bhan M.D. Gary B. Talpos M.D. 《Surgery for obesity and related diseases》2006,2(2):696-103
BACKGROUND: Abnormalities in calcium and vitamin D metabolism have been reported after bariatric surgery. The purpose of this study was to evaluate vitamin D nutritional status among morbidly obese patients before gastric bypass surgery. METHODS: We prospectively studied 279 morbidly obese patients seeking gastric bypass surgery for vitamin D nutritional status as assessed by serum 25-hydroxyvitamin D level. In addition, serum samples were analyzed for calcium, alkaline phosphatase (AP), intact parathyroid hormone (PTH), and 1,25-dihydroxyvitamin D. RESULTS: Mean patient age was 43 +/- 9 years; 87% of the study patients were women, and 72% were white. Serum calcium and AP levels were normal in 88% and 89% of the patients, respectively. Vitamin D depletion, defined as serum 25-hydroxyvitamin D level 相似文献
29.
30.