全文获取类型
收费全文 | 26901篇 |
免费 | 1783篇 |
国内免费 | 164篇 |
专业分类
耳鼻咽喉 | 276篇 |
儿科学 | 714篇 |
妇产科学 | 780篇 |
基础医学 | 3039篇 |
口腔科学 | 711篇 |
临床医学 | 2417篇 |
内科学 | 5363篇 |
皮肤病学 | 483篇 |
神经病学 | 1340篇 |
特种医学 | 1112篇 |
外国民族医学 | 11篇 |
外科学 | 4486篇 |
综合类 | 506篇 |
现状与发展 | 2篇 |
一般理论 | 12篇 |
预防医学 | 2555篇 |
眼科学 | 649篇 |
药学 | 2413篇 |
中国医学 | 144篇 |
肿瘤学 | 1835篇 |
出版年
2023年 | 303篇 |
2022年 | 835篇 |
2021年 | 1246篇 |
2020年 | 693篇 |
2019年 | 876篇 |
2018年 | 1181篇 |
2017年 | 726篇 |
2016年 | 778篇 |
2015年 | 764篇 |
2014年 | 1095篇 |
2013年 | 1326篇 |
2012年 | 1919篇 |
2011年 | 2056篇 |
2010年 | 1174篇 |
2009年 | 880篇 |
2008年 | 1311篇 |
2007年 | 1347篇 |
2006年 | 1236篇 |
2005年 | 1162篇 |
2004年 | 1051篇 |
2003年 | 965篇 |
2002年 | 901篇 |
2001年 | 408篇 |
2000年 | 401篇 |
1999年 | 305篇 |
1998年 | 169篇 |
1997年 | 152篇 |
1996年 | 140篇 |
1995年 | 153篇 |
1994年 | 130篇 |
1993年 | 116篇 |
1992年 | 234篇 |
1991年 | 228篇 |
1990年 | 212篇 |
1989年 | 188篇 |
1988年 | 220篇 |
1987年 | 186篇 |
1986年 | 146篇 |
1985年 | 168篇 |
1984年 | 140篇 |
1983年 | 132篇 |
1982年 | 91篇 |
1981年 | 70篇 |
1980年 | 57篇 |
1979年 | 104篇 |
1978年 | 83篇 |
1977年 | 61篇 |
1976年 | 64篇 |
1974年 | 75篇 |
1973年 | 86篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
John L Hayes 《American journal of orthodontics and dentofacial orthopedics》2005,128(5):557-8; author reply 558
22.
S H Faro A R Turtz R A Koenigsberg F B Mohamed C Y Chen H Stein 《AJNR. American journal of neuroradiology》1997,18(8):1588
The MR imaging features of a paraganglioma of the cauda equina with associated spinal cord cysts are presented. MR imaging showed the tumor to be isointense with the spinal cord on all pulse sequences and to enhance homogeneously. The intramedullary cysts had increased signal intensity on proton density- and T2-weighted images, and involved the cervical and thoracic regions. 相似文献
23.
A. Rashid Choudhury Mohamed S. Al Amin Kamal A. Chaudhri Khalaf R. Al Moutaery 《Child's nervous system》1995,11(2):115-117
A 5-year-old girl presented with a 1-year history of a subcutaneous swelling in the right parietal region. There were no cerebral symptoms or signs. Plain X-ray of the skull showed a lytic bony lesion with sclerotic margin. Computed tomography showed a hypodense, osteolytic lesion with thinned and bulged inner and outer skull tables with intact continuity. There was no intracranial lesion. At operation, the mass was found to be pink and granular, and was totally enucleated. Histology revealed it to be a benign osteoblastoma. 相似文献
24.
Endothelial modulation of vasoconstrictor responses to endothelin-1 in human placental stem villi small arteries. 下载免费PDF全文
S. Sabry F. Mondon M. Levy F. Ferr A. T. Dinh-Xuan 《British journal of pharmacology》1995,115(6):1038-1042
1. The aim of this study was to assess the role of endothelial cells in the modulation of vasocontractile responses to endothelin-1 (ET-1) of human placental vasculature. 2. Isolated stem villi small arteries (diameter = 170-250 microns) were obtained from healthy parturients who underwent caesarean surgery during the 39th week of pregnancy for cephalo-pelvic disproportion. Isometric tension was measured in vascular rings mounted in a myograph system and challenged with ET-1 (10(-12) to 10(-6) M). 3. The vasocontractile response to ET-1 was significantly (P < 0.001) increased in endothelial-denuded (active tension = 1156 +/- 214 mN mm-1) as compared with endothelial-preserved vascular rings (active tension = 458 +/- 48 mN mm-1). This difference was significantly (P < 0.05) but only partly abolished by the NO synthase inhibitor N omega-nitro-L-arginine (L-NOARG, 10(-4) M). 4. In endothelial-preserved rings submaximally precontracted with 5-hydroxytryptamine (10(-6) M), ET-1 (10(-12) to 10(-9) M) induced dose-dependent relaxation (maximum relaxation = 70 +/- 7%) at 10(-9) M, which was followed, at higher doses (10(-8) to 10(-6) M), by a contraction. In contrast, no relaxation was seen in endothelial-denuded rings. The relaxation in rings with endothelium was significantly (P < 0.001) reduced by L-NOARG (10(-4) M. Moreover, it was totally abolished by combined pretreatment with L-NOARG (10(-4) M) and the sulphonylurea glibenclamide (10(-5) M).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
25.
26.
27.
28.
François Béïque Mohamed Ali Scott MacKenzie Mark Hynes 《Journal canadien d'anesthésie》2007,54(2):158-159
29.
30.
Mohamed Eid Fawzy Mohamed Shoukri Walid Hassan Vijayaraghavan Nambiar Miltiadis Stefadouros Charles C Canver 《Catheterization and cardiovascular interventions》2007,69(1):40-46
BACKGROUND: The effect of mitral valve morphology (MVM) on the long-term results of mitral balloon valvuloplasty (MBV) is not well established. The aim of the study was to evaluate the impact of MVM on long-term outcome of MBV. METHODS: Five hundred and eighteen consecutive patients (mean age, 31+/-11 years) who underwent successful MBV were followed up for 0.5-16.5 (mean, 6+/-4.5) years. Patients were divided into two groups according to their mitral echo score (MES) before MBV: group A (n=340; MES8). RESULTS: We report the immediate and long-term clinical and echocardiographic results of the above-mentioned 518 consecutive patients. The mitral valve area was significantly larger in group A than in group B, both immediately after MBV (2.0+/-0.3 vs. 1.82+/-0.3 cm2, respectively; P<0.0001) and also at the last follow-up (1.8+/-0.33 vs. 1.5+/-0.33 cm2, respectively; P<0.0001). Restenosis occurred in 38/340 (11%) in group A vs. 73/178 (41%) in group B (P<0.0001). Actuarial freedom from restenosis at 5, 10, 15 years were 92+/-2%, 85+/-3%, 65+/-6% for group A vs. 72+/-4%, 44+/-5%, 9+/-6% for group B (P<0.001). Event-free survival rates at 5, 10, 15 years for group A were 93+/-1%, 88+/-2%, 66+/-6% vs. 82+/-3%, 59+/-6%, 8+/-7% for group B (P<0.0001). Stepwise Cox multivariate regression analysis identified MES, preprocedure functional class, and postprocedure mitral valve area相似文献