全文获取类型
收费全文 | 21096篇 |
免费 | 1727篇 |
国内免费 | 90篇 |
专业分类
耳鼻咽喉 | 178篇 |
儿科学 | 773篇 |
妇产科学 | 481篇 |
基础医学 | 2610篇 |
口腔科学 | 565篇 |
临床医学 | 3029篇 |
内科学 | 3977篇 |
皮肤病学 | 297篇 |
神经病学 | 1775篇 |
特种医学 | 715篇 |
外科学 | 2614篇 |
综合类 | 549篇 |
一般理论 | 17篇 |
预防医学 | 2556篇 |
眼科学 | 251篇 |
药学 | 1301篇 |
1篇 | |
中国医学 | 22篇 |
肿瘤学 | 1202篇 |
出版年
2023年 | 132篇 |
2021年 | 327篇 |
2020年 | 218篇 |
2019年 | 347篇 |
2018年 | 401篇 |
2017年 | 292篇 |
2016年 | 316篇 |
2015年 | 386篇 |
2014年 | 535篇 |
2013年 | 862篇 |
2012年 | 1136篇 |
2011年 | 1202篇 |
2010年 | 665篇 |
2009年 | 648篇 |
2008年 | 959篇 |
2007年 | 1135篇 |
2006年 | 1011篇 |
2005年 | 1020篇 |
2004年 | 927篇 |
2003年 | 848篇 |
2002年 | 837篇 |
2001年 | 473篇 |
2000年 | 552篇 |
1999年 | 505篇 |
1998年 | 311篇 |
1997年 | 261篇 |
1996年 | 278篇 |
1995年 | 265篇 |
1994年 | 229篇 |
1993年 | 223篇 |
1992年 | 367篇 |
1991年 | 362篇 |
1990年 | 397篇 |
1989年 | 348篇 |
1988年 | 321篇 |
1987年 | 308篇 |
1986年 | 277篇 |
1985年 | 297篇 |
1984年 | 220篇 |
1983年 | 178篇 |
1982年 | 146篇 |
1981年 | 133篇 |
1980年 | 127篇 |
1979年 | 187篇 |
1978年 | 153篇 |
1977年 | 130篇 |
1974年 | 138篇 |
1973年 | 137篇 |
1972年 | 128篇 |
1971年 | 125篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
H Bell A Bj?rneboe B Eidsvoll K R Norum N Raknerud K Try Y Thomassen C A Drevon 《Alcohol and alcoholism (Oxford, Oxfordshire)》1992,27(1):39-46
The concentration of alpha-tocopherol was measured in liver biopsy specimens obtained from 83 patients with alcoholic and non-alcoholic liver diseases. The mean hepatic vitamin E content (as alpha-tocopherol) was significantly lower in 23 patients with alcoholic cirrhosis (17.6 +/- 12.1 nmol/mg wet weight liver), compared with 12 patients with normal liver histology (39.2 +/- 29.7 nmol/mg, P less than 0.01). The mean serum concentration of alpha-tocopherol was lower in patients with alcoholic cirrhosis (13.9 +/- 7.0 mumol/l) than in individuals with alcoholic fatty liver (21.3 +/- 9.3 mumol/l, P less than 0.01) and patients with normal liver histology (23.4 +/- 11.6 mumol/l, P less than 0.01). A decreased ratio of serum alpha-tocopherol/total serum lipids was also observed in patients with alcoholic cirrhosis, compared with patients with normal liver histology (P less than 0.05). There was a significant correlation between concentrations of alpha-tocopherol in liver and serum (r = 0.43, P less than 0.001). Furthermore, serum alpha-tocopherol correlated with retinol (r = 0.53, P less than 0.001), selenium (r = 0.45, P less than 0.001), and albumin (r = 0.37, P less than 0.001) in serum. We suggest that the reduced content of hepatic alpha-tocopherol observed in some patients may play a role in ethanol-induced lipid peroxidation. 相似文献
63.
Howard Weinstein Michael A. King Christopher P. Reinhardt Brenda A. McSherry Jeffrey A. Leppo 《Journal of nuclear cardiology》1994,1(1):39-51
Background
Simultaneous dual-radionuclide technetium 99m/thallium 201 scintigraphy can potentially produce perfectly aligned stress and rest images in less time than conventional protocols. However, interradionuclide crossover limits diagnostic accuracy. Accordingly, we evaluated99mTc and201Tl crossover in line and heart phantoms. 相似文献64.
65.
Paul A.T. Kelly Isobel M. Ritchie Meharpal Sangra Miranda J.A. Cursham Emma M. Dickson Brenda Kelly Fiona P. Neilson M. Jason Reidy Martha C. Stevens 《Brain research》1994,665(2)
Cerebral blood flow and glucose utilization were measured in rat neocortex, hippocampus and striatum following methylenedioxymethamphetamine injection (5 mg/kg, i.v.), using the tracers [14C]iodoantipyrine and [14C]2-deoxyglucose, respectively. In control rats, blood flow was coupled to glucose metabolism, but in methylenedioxymethamphetamine-treated rats, marked hyperperfusion was measured in frontal and parietal cortex with no change in glucose use. This suggests that methylenedioxymethamphetamine has the potential to disrupt cerebrovascular control. 相似文献
66.
Pancreatitis after parathyroidectomy 总被引:1,自引:0,他引:1
N J London D M Lloyd H Pearson J P Neoptolemos P R Bell 《The British journal of surgery》1986,73(9):766-767
67.
P M McCarthy V F Trastek D G Bell G R Buttermann J M Piehler W S Payne L H Weiland P C Pairolero 《The Annals of thoracic surgery》1988,45(2):203-205
The effectiveness of fibrin glue as a biological sealant for pulmonary air leaks was determined in 16 dogs. A standardized pleural defect was made in the left lower lobe, and the quantity of air passing through a chest tube was assessed with a Collins respirometer. For the 8 randomly assigned control animals, the air leak decreased over 90 minutes from a mean of 1.4 L/min to a mean of 1.1 L/min (mean decrease, 19.8%). In the 8 randomly assigned fibrin glue-treated animals, the air leak decreased from a mean of 2.1 L/min to a mean of 0.5 L/min (mean decrease, 80.8%) (p less than 0.0001). Postoperative evaluation of survivors disclosed no increased adhesions in the glue-treated animals and complete resorption of the glue at 3 months. We conclude that in this animal model, fibrin glue reduced the size of pulmonary air leaks in the early period after thoracotomy and did not lead to increased intrapleural adhesions. 相似文献
68.
69.
70.