全文获取类型
收费全文 | 40407篇 |
免费 | 2178篇 |
国内免费 | 152篇 |
专业分类
耳鼻咽喉 | 544篇 |
儿科学 | 1024篇 |
妇产科学 | 844篇 |
基础医学 | 5159篇 |
口腔科学 | 2249篇 |
临床医学 | 2880篇 |
内科学 | 10398篇 |
皮肤病学 | 972篇 |
神经病学 | 3323篇 |
特种医学 | 840篇 |
外科学 | 5947篇 |
综合类 | 253篇 |
一般理论 | 14篇 |
预防医学 | 2981篇 |
眼科学 | 716篇 |
药学 | 2183篇 |
中国医学 | 139篇 |
肿瘤学 | 2271篇 |
出版年
2023年 | 245篇 |
2022年 | 529篇 |
2021年 | 1444篇 |
2020年 | 777篇 |
2019年 | 1138篇 |
2018年 | 1337篇 |
2017年 | 882篇 |
2016年 | 984篇 |
2015年 | 1113篇 |
2014年 | 1638篇 |
2013年 | 2020篇 |
2012年 | 3282篇 |
2011年 | 3442篇 |
2010年 | 1953篇 |
2009年 | 1629篇 |
2008年 | 2749篇 |
2007年 | 2790篇 |
2006年 | 2688篇 |
2005年 | 2604篇 |
2004年 | 2208篇 |
2003年 | 1992篇 |
2002年 | 1780篇 |
2001年 | 266篇 |
2000年 | 203篇 |
1999年 | 266篇 |
1998年 | 313篇 |
1997年 | 242篇 |
1996年 | 212篇 |
1995年 | 203篇 |
1994年 | 160篇 |
1993年 | 121篇 |
1992年 | 141篇 |
1991年 | 108篇 |
1990年 | 74篇 |
1989年 | 70篇 |
1988年 | 70篇 |
1987年 | 69篇 |
1986年 | 67篇 |
1985年 | 78篇 |
1984年 | 69篇 |
1983年 | 65篇 |
1982年 | 49篇 |
1981年 | 57篇 |
1980年 | 70篇 |
1979年 | 51篇 |
1978年 | 48篇 |
1977年 | 57篇 |
1976年 | 41篇 |
1974年 | 30篇 |
1973年 | 31篇 |
排序方式: 共有10000条查询结果,搜索用时 678 毫秒
51.
The authors present a synthesis of the proposals put forth by the health sector of Venezuela during the framing of the new Venezuelan Constitution. They summarize the background to the National Constituent Assembly and the legal framework typical of the health sector at that time, identify the methodological aspects that substantiated the health topics included in the new Constitution, and analyze the articles that shape the current constitutional health framework in Venezuela, summarizing their most important features and comparing them with neoliberal health proposals. 相似文献
52.
53.
Chu‐Lin Tsai MD MPH Justin A. Sobrino BS Carlos A. Camargo Jr MD DrPH 《Academic emergency medicine》2008,15(12):1275-1283
Objectives: Little is known about recent trends in U.S. emergency department (ED) visits for acute exacerbation of chronic obstructive pulmonary disease (AECOPD) or about ED management of AECOPD. This study aimed to describe the epidemiology of ED visits for AECOPD and to evaluate concordance with guideline‐recommended care. Methods: Data were obtained from National Hospital Ambulatory Medical Care Survey (NHAMCS). ED visits for AECOPD, during 1993 to 2005, were identified using the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD‐9‐CM) codes. Concordance with guideline recommendations was evaluated using process measures. Results: Over the 13‐year study period, there was an average annual 0.6 million ED visits for AECOPD, and the visit rates for AECOPD were consistently high (3.2 per 1,000 U.S. population; Ptrend = 0.13). The trends in the use of chest radiograph, pulse oximetry, or bronchodilator remained stable (all Ptrend > 0.5). By contrast, the use of systemic corticosteroids increased from 29% in 1993–1994 to 60% in 2005, antibiotics increased from 14% to 42%, and methylxanthines decreased from 15% to <1% (all Ptrend < 0.001). Multivariable analysis showed patients in the South (vs. the Northeast) were less likely to receive systemic corticosteroids (odds ratio [OR] = 0.6; 95% confidence interval [CI] = 0.4 to 0.9). Conclusions: The high burden of ED visits for AECOPD persisted. Overall concordance with guideline‐recommended care for AECOPD was moderate, and some emergency treatments had improved over time. 相似文献
54.
55.
56.
Prof. Dr. Carlos Mainini 《Lung》1940,95(3-4):365-368
57.
58.
David Jiménez Castro Gema Díaz David Martí Carlos Escobar Javier Ortega Sergio García-Rull Joaquin Picher Antonio Sueiro 《Blood coagulation & fibrinolysis》2007,18(2):173-177
This study aimed to determine whether a weight-adjusted dose of subcutaneous enoxaparin is as effective and safe as oral acenocoumarol for the secondary prophylaxis of pulmonary embolism. Three hundred and eighty consecutive noncancer outpatients hospitalized with an episode of symptomatic pulmonary embolism selected treatment with acenocoumarol or enoxaparin at a dose of 1 mg/kg once daily after being informed of the type of administration and expected frequency of laboratory monitoring for both medicinal products. Endpoints were symptomatic recurrent thromboembolic events evaluated by standard objective testing, and a composite endpoint of recurrent venous thromboembolism, major bleeding, and death from any cause. One hundred and ninety-nine patients (52%) chose acenocoumarol therapy and 181 chose enoxaparin monotherapy. Four patients in the enoxaparin group (2.2%) and six patients in the acenocoumarol group (3%) had an objective thromboembolic recurrence (hazard ratio, 1.35; 95% confidence interval, 0.38-4.79; P = 0.64). Nine patients in the enoxaparin group (5.0%) had a hemorrhagic complication compared with 11 in the acenocoumarol group (5.5%) (P = 0.81). The hospital length of stay was shorter with enoxaparin compared with acenocoumarol (11 versus 16 days, P = 0.0001). Enoxaparin is as effective and safe as acenocoumarol in the secondary prevention of recurrent thromboembolic disease and is associated with shorter hospitalization. 相似文献
59.
D-dimer has proved a useful diagnostic tool for the exclusion of deep venous thrombosis (DVT). The objective of this paper was to evaluate the diagnostic performance of a diagnostic algorithm combining clinical probability and D-dimer in outpatients receiving oral anticoagulant treatment (OAT) similar to those regularly applied to nonanticoagulated individuals. We enrolled 70 outpatients on OAT who presented with clinically suspected DVT; a standard diagnostic algorithm including clinical evaluation using the modified Wells score and a quantitative immunoturbidimetric D-dimer assay (STA Liatest D-Di; Diagnostica Stago, Asniéres sur Seine, France) was used. A 3-month follow-up period was applied for those patients in whom DVT was initially excluded. The prevalence of DVT was 18.5% (13/70); four of the diagnoses were made during the 3-month follow-up period. The sensitivity, specificity and negative predictive value of D-dimer were 69.2% (95 confidence interval, 42.4-87.3), 47.4% (95% confidence interval, 35.0-60.1) and 87.1% (95% confidence interval, 71.1-94.9), respectively. In conclusion, D-dimer is of limited value in outpatients on OAT presenting with clinically suspected DVT and should be omitted in such individuals; these patients should always undergo compression venous ultrasound, and repeat ultrasonography within 1 week might be warranted in cases with an initial negative examination. 相似文献
60.