全文获取类型
收费全文 | 75482篇 |
免费 | 3899篇 |
国内免费 | 1579篇 |
专业分类
耳鼻咽喉 | 387篇 |
儿科学 | 1818篇 |
妇产科学 | 905篇 |
基础医学 | 5100篇 |
口腔科学 | 288篇 |
临床医学 | 10135篇 |
内科学 | 19157篇 |
皮肤病学 | 125篇 |
神经病学 | 3547篇 |
特种医学 | 6477篇 |
外国民族医学 | 2篇 |
外科学 | 9520篇 |
综合类 | 12435篇 |
现状与发展 | 3篇 |
预防医学 | 2757篇 |
眼科学 | 484篇 |
药学 | 5002篇 |
46篇 | |
中国医学 | 1637篇 |
肿瘤学 | 1135篇 |
出版年
2024年 | 69篇 |
2023年 | 992篇 |
2022年 | 1771篇 |
2021年 | 2863篇 |
2020年 | 2537篇 |
2019年 | 2218篇 |
2018年 | 2272篇 |
2017年 | 2072篇 |
2016年 | 2180篇 |
2015年 | 2389篇 |
2014年 | 5193篇 |
2013年 | 4890篇 |
2012年 | 4392篇 |
2011年 | 4761篇 |
2010年 | 4018篇 |
2009年 | 4003篇 |
2008年 | 4097篇 |
2007年 | 4213篇 |
2006年 | 3788篇 |
2005年 | 3167篇 |
2004年 | 2476篇 |
2003年 | 2107篇 |
2002年 | 1682篇 |
2001年 | 1657篇 |
2000年 | 1258篇 |
1999年 | 1157篇 |
1998年 | 1092篇 |
1997年 | 1019篇 |
1996年 | 742篇 |
1995年 | 800篇 |
1994年 | 665篇 |
1993年 | 573篇 |
1992年 | 523篇 |
1991年 | 419篇 |
1990年 | 370篇 |
1989年 | 324篇 |
1988年 | 305篇 |
1987年 | 274篇 |
1986年 | 212篇 |
1985年 | 260篇 |
1984年 | 223篇 |
1983年 | 103篇 |
1982年 | 189篇 |
1981年 | 136篇 |
1980年 | 114篇 |
1979年 | 110篇 |
1978年 | 88篇 |
1977年 | 64篇 |
1976年 | 52篇 |
1975年 | 25篇 |
排序方式: 共有10000条查询结果,搜索用时 271 毫秒
41.
42.
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43.
《Saudi Pharmaceutical Journal》2022,30(6):669-678
BackgroundIschemia reperfusion (I/R) play an imperative role in the expansion of cardiovascular disease. Sinomenine (SM) has been exhibited to possess antioxidant, anticancer, anti-inflammatory, antiviral and anticarcinogenic properties. The aim of the study was scrutinized the cardioprotective effect of SM against I/R injury in rat.MethodsRat were randomly divided into normal control (NC), I/R control and I/R + SM (5, 10 and 20 mg/kg), respectively. Ventricular arrhythmias, body weight and heart weight were estimated. Antioxidant, inflammatory cytokines, inflammatory mediators and plasmin system indicator were accessed.ResultsPre-treated SM group rats exhibited the reduction in the duration and incidence of ventricular fibrillation, ventricular ectopic beat (VEB) and ventricular tachycardia along with suppression of arrhythmia score during the ischemia (30 and 120 min). SM treated rats significantly (P < 0.001) altered the level of antioxidant parameters. SM treatment significantly (P < 0.001) repressed the level of creatine kinase MB (CK-MB), creatine kinase (CK) and troponin I (Tnl). SM treated rats significantly (P < 0.001) repressed the tissue factor (TF), thromboxane B2 (TXB2), plasminogen activator inhibitor 1 (PAI-1) and plasma fibrinogen (Fbg) and inflammatory cytokines and inflammatory mediators.ConclusionOur result clearly indicated that SM plays anti-arrhythmia effect in I/R injury in the rats via alteration of oxidative stress and inflammatory reaction. 相似文献
44.
45.
46.
目的 了解2009-2019年西安市肺结核的流行特征及治疗转归情况,为完善西安市肺结核防治策略提供依据。方法 收集2009-2019年《传染病信息管理系统》中登记的肺结核患者病案信息数据,通过描述性研究方法对肺结核流行病学特征和治疗转归情况进行分析。结果 2009-2019年间西安市肺结核年平均发病率为49.06/10万。郊县、郊区、城区肺结核年平均发病率分别为54.13/10万、47.46/10万和46.19/10万;男性发病率是女性的1.85倍。职业分布排在前5位的为农民(47.48%),家政、家务及待业(14.65%),离退人员(9.55%),学生(8.63%)和工人(5.23%)。利福平敏感或耐药性未知患者的成功治疗率平均为98.03%,利福平耐药患者治疗成功率为51.47%。结论 西安市近年来肺结核发病率和治疗率呈增长趋势,利福平耐药患者治疗成功率较低,要加强对重点人群的健康促进工作,加大肺结核发现力度及患者治疗管理工作。 相似文献
47.
48.
49.
50.
《Journal of vascular and interventional radiology : JVIR》2020,31(5):760-768.e1
PurposeTo investigate dynamic variables obtained from retrospective computed tomography angiography for ability to predict thoracic endovascular aortic repair (TEVAR) outcomes in patients with complicated type B aortic dissection (cTBAD).Materials and MethodsSeventy-nine patients with cTBAD who received TEVAR from March 2009 to June 2018 were retrospectively enrolled. Relative true lumen area (r-TLA) was computed at the level of tracheal bifurcation every 5% of all R-R intervals. Parameters that reflect the state of intimal motion were evaluated, including difference between maximum and minimum r-TLA (D-TLA) and true lumen collapse. The endpoints comprised early (≤ 30 days) and late (> 30 days) outcomes after intervention.ResultsOverall early mortality rate was 13.9% (11/79), and early adverse events rate was 24.1% (19/79). Patients who received TEVAR within 2 days of symptom onset demonstrated the worst outcomes. A longer time of r-TLA < 25% in 1 cardiac cycle (P = .049) and larger D-TLA (P < .001) were correlated to an increased early death. In addition, D-TLA was an independent predictor of early mortality. Area under the curve of D-TLA was 0.849 (95% confidence interval 0.730–0.967) for predicting early mortality and 0.742 (95% CI 0.611–0.873) for predicting early adverse events. Survival and event-free survival rates during follow-up were decreased in the D-TLA > 21.5% group compared with the D-TLA ≤ 21.5% group (all P < .001).ConclusionsLarger D-TLA is correlated with worse postoperative outcomes and might be a crucial parameter for future risk stratification in patients with cTBAD. 相似文献