全文获取类型
收费全文 | 236680篇 |
免费 | 14964篇 |
国内免费 | 1011篇 |
专业分类
耳鼻咽喉 | 2524篇 |
儿科学 | 6140篇 |
妇产科学 | 4432篇 |
基础医学 | 29461篇 |
口腔科学 | 4363篇 |
临床医学 | 24202篇 |
内科学 | 49911篇 |
皮肤病学 | 3244篇 |
神经病学 | 23686篇 |
特种医学 | 10580篇 |
外国民族医学 | 13篇 |
外科学 | 37106篇 |
综合类 | 2564篇 |
现状与发展 | 1篇 |
一般理论 | 177篇 |
预防医学 | 16558篇 |
眼科学 | 5542篇 |
药学 | 15530篇 |
1篇 | |
中国医学 | 322篇 |
肿瘤学 | 16298篇 |
出版年
2023年 | 1335篇 |
2022年 | 2195篇 |
2021年 | 5340篇 |
2020年 | 3052篇 |
2019年 | 5059篇 |
2018年 | 6064篇 |
2017年 | 4451篇 |
2016年 | 4868篇 |
2015年 | 5757篇 |
2014年 | 8372篇 |
2013年 | 11298篇 |
2012年 | 17292篇 |
2011年 | 18025篇 |
2010年 | 10136篇 |
2009年 | 9363篇 |
2008年 | 15890篇 |
2007年 | 16674篇 |
2006年 | 16220篇 |
2005年 | 16070篇 |
2004年 | 15114篇 |
2003年 | 13796篇 |
2002年 | 13201篇 |
2001年 | 1939篇 |
2000年 | 1447篇 |
1999年 | 2026篇 |
1998年 | 2916篇 |
1997年 | 2330篇 |
1996年 | 2046篇 |
1995年 | 1852篇 |
1994年 | 1600篇 |
1993年 | 1573篇 |
1992年 | 999篇 |
1991年 | 944篇 |
1990年 | 797篇 |
1989年 | 800篇 |
1988年 | 720篇 |
1987年 | 661篇 |
1986年 | 680篇 |
1985年 | 725篇 |
1984年 | 932篇 |
1983年 | 817篇 |
1982年 | 1067篇 |
1981年 | 984篇 |
1980年 | 871篇 |
1979年 | 478篇 |
1978年 | 529篇 |
1977年 | 463篇 |
1976年 | 442篇 |
1975年 | 338篇 |
1974年 | 310篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
Stress Testing Versus CT Angiography in Patients With Diabetes and Suspected Coronary Artery Disease
Abhinav Sharma Adrian Coles Nishant K. Sekaran Neha J. Pagidipati Michael T. Lu Daniel B. Mark Kerry L. Lee Hussein R. Al-Khalidi Udo Hoffmann Pamela S. Douglas 《Journal of the American College of Cardiology》2019,73(8):893-902
Background
The optimal noninvasive test (NIT) for patients with diabetes and stable symptoms of coronary artery disease (CAD) is unknown.Objectives
The purpose of this study was to assess whether a diagnostic strategy based on coronary computed tomographic angiography (CTA) is superior to functional stress testing in reducing adverse cardiovascular (CV) outcomes (CV death or myocardial infarction [MI]) among symptomatic patients with diabetes.Methods
PROMISE (Prospective Multicenter Imaging Study for Evaluation of Chest Pain) was a randomized trial evaluating an initial strategy of CTA versus functional testing in stable outpatients with symptoms suggestive of CAD. The study compared CV outcomes in patients with diabetes (n = 1,908 [21%]) and without diabetes (n = 7,058 [79%]) based on their randomization to CTA or functional testing.Results
Patients with diabetes (vs. without) were similar in age (median 61 years vs. 60 years) and sex (female 54% vs. 52%) but had a greater burden of CV comorbidities. Patients with diabetes who underwent CTA had a lower risk of CV death/MI compared with functional stress testing (CTA: 1.1% [10 of 936] vs. stress testing: 2.6% [25 of 972]; adjusted hazard ratio: 0.38; 95% confidence interval: 0.18 to 0.79; p = 0.01). There was no significant difference in nondiabetic patients (CTA: 1.4% [50 of 3,564] vs. stress testing: 1.3% [45 of 3,494]; adjusted hazard ratio: 1.03; 95% confidence interval: 0.69 to 1.54; p = 0.887; interaction term for diabetes p value = 0.02).Conclusions
In diabetic patients presenting with stable chest pain, a CTA strategy resulted in fewer adverse CV outcomes than a functional testing strategy. CTA may be considered as the initial diagnostic strategy in this subgroup. (PROspective Multicenter Imaging Study for Evaluation of Chest Pain [PROMISE]; NCT01174550) 相似文献3.
4.
Barry L Eppley A Michael Sadove David Hennon John A van Aalst 《The Cleft palate-craniofacial journal》2006,43(3):374-378
OBJECTIVE: A series of nasopharyngeal appliance designs is presented that represents our evolving experience over a 20-year period in the adjunctive use of prosthetic stents in the surgical correction of nasopharyngeal stenosis. DESIGN: Retrospective assessment of effectiveness of two nasopharyngeal stenosis hollow stent designs in a consecutive series of patients for relief of nasal obstructive symptoms. SETTING: Tertiary academic medical center, Craniofacial Program at Children's Hospital. PATIENTS: Four patients with nasopharyngeal stenosis were treated with a preoperatively fabricated stent made from a clasped palatal appliance onto which hollow acrylic conduits were extended through surgically re-created pharyngeal ports. A subsequent set of four patients with nasopharyngeal stenosis were treated with intraoperatively-fashioned silastic grommets, as opposed to palatal appliances. INTERVENTIONS: Postoperative intraoral stenting of nasopharyngeal ports. MAIN OUTCOME MEASURES: Maintenance of pharyngeal port opening after 1 year, improvement in nasal airway obstructive symptoms. RESULTS: The palatal appliance stents were less well tolerated and had a lower maintenance of port patency after device removal (4 of 8, 50%). The silastic grommets provided better retention into the ports and increased patient tolerance, as well as better 1-year port maintenance (6 of 8, 75%). CONCLUSIONS: The grommet stent appliance offers numerous advantages over a conventional dental-clasped appliance for prosthetic nasopharyngeal stenting, including obviation of extensive preoperative preparation, ease of insertion and removal, and exchange of air during the stenting period. Improved nasopharyngeal patency with this device may be due to greater patient tolerance and subsequent longer use. 相似文献
5.
Hideki Kawaguchi Kazuko Masuo Tomohiro Katsuya Ken Sugimoto Hiromi Rakugi Toshio Ogihara Michael L Tuck 《Hypertension research》2006,29(12):951-959
High blood pressure (BP) is a major determinant of cardiovascular events in obesity. The beta2- and beta3-adrenoceptor polymorphisms are associated with obesity and hypertension. In the present study, we examine the relationships of beta2- and beta3-adrenoceptor polymorphisms with further weight gain-induced BP elevation in obese subjects. Changes in BP, body weight, total body fat-mass, waist-to-hip ratio, plasma norepinephrine (NE) and leptin levels, and beta2(Arg16Gly)- and beta3(Trp64Arg)-adrenoceptor polymorphisms were measured periodically over a 5-year period in 55 entry obese (body mass index [BMI]> or =25.0 kg/m(2)) normotensive (BP<140/90 mmHg) men. BP elevation and weight gain were defined as > or =10% increases from entry levels over 5 years in mean BP or BMI. Obese subjects with weight gain, BP elevation or weight gain-induced BP elevation had higher frequencies of the Gly16 allele of Arg16GIy and Arg64 allele of Trp64Arg. Subjects carrying the Gly16 or Arg64 alleles had significantly greater total fat-mass and waist-to-hip ratio at entry and over a 5-year period compared to the subjects who did not carry these polymorphisms. Subjects carrying the Gly16 allele had similar levels of plasma NE, higher levels of plasma leptin and a lower slope of the regression lines between plasma leptin and NE levels. Those carrying the Arg64 allele had higher plasma NE levels at entry and over a 5-year period compared to the subjects without the Arg64 allele, but plasma leptin levels and slopes were similar. The findings demonstrate that the Arg64 allele of the beta3-adrenoceptor polymorphisms relates to weight gain-induced BP elevation accompanying high plasma NE (heightened sympathetic activity) in obese men. The Gly16 allele of the beta2-adrenoceptor polymorphisms links to weight gain-induced BP elevation associated with leptin resistance. beta2- and beta3-adrenoceptor polymorphisms could predict the future BP elevation and further weight gain-induced BP elevation in originally obese subjects. 相似文献
6.
7.
8.
9.
Dear Sir In the recently published Task force report, under section Fibrinolyticregimens, the authors recommend not to re-administerstreptokinase for at least 10 years. The reference supportingthis statement is Ref. 51. After evaluating this paper and lookinginto the literature my comments 相似文献
10.