全文获取类型
收费全文 | 138968篇 |
免费 | 11496篇 |
国内免费 | 3702篇 |
专业分类
耳鼻咽喉 | 588篇 |
儿科学 | 4028篇 |
妇产科学 | 1386篇 |
基础医学 | 9502篇 |
口腔科学 | 1627篇 |
临床医学 | 19284篇 |
内科学 | 41557篇 |
皮肤病学 | 938篇 |
神经病学 | 3228篇 |
特种医学 | 3041篇 |
外国民族医学 | 2篇 |
外科学 | 14189篇 |
综合类 | 23677篇 |
现状与发展 | 16篇 |
一般理论 | 6篇 |
预防医学 | 7381篇 |
眼科学 | 512篇 |
药学 | 12360篇 |
136篇 | |
中国医学 | 8757篇 |
肿瘤学 | 1951篇 |
出版年
2024年 | 374篇 |
2023年 | 2459篇 |
2022年 | 4057篇 |
2021年 | 5816篇 |
2020年 | 5874篇 |
2019年 | 5229篇 |
2018年 | 4950篇 |
2017年 | 4969篇 |
2016年 | 5032篇 |
2015年 | 5211篇 |
2014年 | 9555篇 |
2013年 | 10400篇 |
2012年 | 7881篇 |
2011年 | 8786篇 |
2010年 | 6929篇 |
2009年 | 6641篇 |
2008年 | 6442篇 |
2007年 | 6590篇 |
2006年 | 5938篇 |
2005年 | 5404篇 |
2004年 | 4324篇 |
2003年 | 3714篇 |
2002年 | 3269篇 |
2001年 | 2931篇 |
2000年 | 2375篇 |
1999年 | 2176篇 |
1998年 | 1823篇 |
1997年 | 1769篇 |
1996年 | 1520篇 |
1995年 | 1426篇 |
1994年 | 1367篇 |
1993年 | 1026篇 |
1992年 | 959篇 |
1991年 | 877篇 |
1990年 | 702篇 |
1989年 | 680篇 |
1988年 | 595篇 |
1987年 | 517篇 |
1986年 | 469篇 |
1985年 | 567篇 |
1984年 | 462篇 |
1983年 | 294篇 |
1982年 | 333篇 |
1981年 | 322篇 |
1980年 | 238篇 |
1979年 | 197篇 |
1978年 | 178篇 |
1977年 | 141篇 |
1976年 | 133篇 |
1975年 | 76篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
《The Journal of thoracic and cardiovascular surgery》2023,165(1):94-103.e24
ObjectiveNew-onset postoperative atrial fibrillation (POAF) after cardiac surgery is common, with rates up to 60%. POAF has been associated with early and late stroke, but its association with other cardiovascular outcomes is less known. The objective was to perform a meta-analysis of the studies reporting the association of POAF with perioperative and long-term outcomes in patients with cardiac surgery.MethodsWe performed a systematic review and a meta-analysis of studies that presented outcomes for cardiac surgery on the basis of the presence or absence of POAF. MEDLINE, EMBASE, and the Cochrane Library were assessed; 57 studies (246,340 patients) were selected. Perioperative mortality was the primary outcome. Inverse variance method and random model were performed. Leave-one-out analysis, subgroup analyses, and metaregression were conducted.ResultsPOAF was associated with perioperative mortality (odds ratio [OR], 1.92; 95% confidence interval [CI], 1.58-2.33), perioperative stroke (OR, 2.17; 95% CI, 1.90-2.49), perioperative myocardial infarction (OR, 1.28; 95% CI, 1.06-1.54), perioperative acute renal failure (OR, 2.74; 95% CI, 2.42-3.11), hospital (standardized mean difference, 0.80; 95% CI, 0.53-1.07) and intensive care unit stay (standardized mean difference, 0.55; 95% CI, 0.24-0.86), long-term mortality (incidence rate ratio [IRR], 1.54; 95% CI, 1.40-1.69), long-term stroke (IRR, 1.33; 95% CI, 1.21-1.46), and longstanding persistent atrial fibrillation (IRR, 4.73; 95% CI, 3.36-6.66).ConclusionsThe results suggest that POAF after cardiac surgery is associated with an increased occurrence of most short- and long-term cardiovascular adverse events. However, the causality of this association remains to be established. 相似文献
2.
《Vaccine》2020,38(3):570-577
IntroductionPediatric pneumococcal pneumonia complicated by parapneumonic pleural effusion/empyema (PPE/PE) remains a major concern despite general immunization with pneumococcal conjugate vaccines (PCVs).MethodsIn a nationwide pediatric hospital surveillance study in Germany we identified 584 children <18 years of age with bacteriologically confirmed PPE/PE from October 2010 to June 2018. Streptococcus pneumoniae was identified by culture and/or PCR of blood samples and/or pleural fluid and serotyped.ResultsS. pneumoniae was identified in 256 of 584 (43.8%) children by culture (n = 122) and/or PCR (n = 207). The following pneumococcal serotypes were detected in 114 children: serotype 3 (42.1%), 1 (25.4%), 7F (12.3%), 19A (7.9%), other PCV13 serotypes (4.4%) and non-PCV13 serotypes (7.9%). Between October 2010 and June 2014 serotype 1 (38.1%) and serotype 3 (25.4%) were most prevalent, whereas between July 2014 and June 2018 serotype 3 (62.7%) and non-PCV13 serotypes (15.7%) were dominant. Compared to children with other pneumococcal serotypes, children with serotype 3 associated PPE/PE were younger (median 3.2 years [IQR 2.1–4.3 years] vs. median 5.6 years [IQR 3.8–8.2 years]; p < 0.001) and more frequently admitted to intensive care (43 [89.6%] vs. 48 [73.8%]; p = 0.04). Seventy-six of 114 (66.7%) children with pneumococcal PPE/PE had been vaccinated with pneumococcal vaccines. Thirty-nine of 76 (51.3%) had received a vaccine covering the serotype detected. Thirty of these 39 breakthrough cases were age-appropriately vaccinated with PCV13 and considered vaccine failures, including 26 children with serotype 3, three children with serotype 19A and one child with serotype 1.ConclusionFollowing the introduction of PCV13 in general childhood vaccination we observed a strong emergence of serotype 3 associated PPE/PE in the German pediatric population, including a considerable number of younger children with serotype 3 vaccine breakthrough cases and failures. Future PCVs should not only cover newly emerging serotypes, but also include a more effective component against serotype 3. 相似文献
3.
4.
《Mayo Clinic proceedings. Mayo Clinic》2022,97(12):2271-2281
ObjectiveTo investigate the association between type 1 diabetes mellitus (T1D) and type 2 diabetes mellitus (T2D) with risk of sudden cardiac arrest (SCA).MethodsIn a prospective community-based study of SCA from February 1, 2002, through November 30, 2019, we ascertained 2771 cases age 18 years of age or older and matched them to 8313 controls based on geography, age, sex, and race/ethnicity. We used logistic regression to evaluate the independent association between diabetes, T1D, T2D, and SCA.ResultsPatients had a mean age of 64.5±15.9 years, were 33.3% female and 23.9% non-White race. Overall, 36.7% (n=1016) of cases and 23.8% (n=1981) of controls had diabetes. Among individuals with diabetes, the proportion of T1D was 6.5% (n=66) among cases and 2.0% among controls (n=40). Diabetes was associated with 1.5-times higher odds of SCA. Compared with those without diabetes, the odds ratio and 95% CI for SCA was 4.36 (95% CI, 2.81 to 6.75; P<.001) in T1D and 1.45 (95% CI, 1.30 to 1.63; P<.001) in T2D after multivariable adjustment. Among those with diabetes, the odds of having SCA were 2.41 times higher in T1D than in T2D (95% CI, 1.53 to 3.80; P<.001). Cases of SCA with T1D were more likely to have an unwitnessed arrest, less likely to receive resuscitation, and less likely to survive compared with those with T2D.ConclusionType 1 diabetes was more strongly associated with SCA compared with T2D and had less favorable outcomes following resuscitation. Diabetes type could influence the approach to risk stratification and prevention of SCA. 相似文献
5.
6.
《The Journal of thoracic and cardiovascular surgery》2023,165(1):149-158.e4
BackgroundCoronary artery bypass grafting (CABG) improves survival in patients with heart failure and severely reduced left ventricular systolic function (LVEF). Limited data exist regarding adverse cardiovascular event rates after CABG in patients with heart failure with midrange ejection fraction (HFmrEF; LVEF > 40% and < 55%).MethodsWe analyzed data on isolated CABG patients from the Veterans Affairs national database (2010-2019). We stratified patients into control (normal LVEF and no heart failure), HFmrEF, and heart failure with reduced LVEF (HFrEF) groups. We compared all-cause mortality and heart failure hospitalization rates between groups with a Cox model and recurrent events analysis, respectively.ResultsIn 6533 veterans, HFmrEF and HFrEF was present in 1715 (26.3%) and 566 (8.6%) respectively; the control group had 4252 (65.1%) patients. HFrEF patients were more likely to have diabetes mellitus (59%), insulin therapy (36%), and previous myocardial infarction (31%). Anemia was more prevalent in patients with HFrEF (49%) as was a lower serum albumin (mean, 3.6 mg/dL). Compared with the control group, a higher risk of death was observed in the HFmrEF (hazard ratio [HR], 1.3 [1.2-1.5)] and HFrEF (HR, 1.5 [1.2-1.7]) groups. HFmrEF patients had the higher risk of myocardial infarction (subdistribution HR, 1.2 [1-1.6]; P = .04). Risk of heart failure hospitalization was higher in patients with HFmrEF (HR, 4.1 [3.5-4.7]) and patients with HFrEF (HR, 7.2 [6.2-8.5]).ConclusionsHeart failure with midrange ejection fraction negatively affects survival after CABG. These patients also experience higher rates myocardial infarction and heart failure hospitalization. 相似文献
7.
Could non-HDL-cholesterol be a better marker of atherogenic dyslipidemia in obstructive sleep apnea?
《Sleep medicine》2021
Background/objectiveObstructive sleep apnea (OSA) is independently associated with dyslipidemia, a surrogate marker of atherosclerosis. Low-density lipoprotein (LDL)-cholesterol is accepted as a major independent risk factor for cardiovascular disease. However, non-high-density lipoprotein (HDL)-cholesterol is a better marker of atherogenic dyslipidemia and recommended as a target of lipid lowering therapy. We aimed to assess the prevalence of atherogenic dyslipidemia, and relationship between OSA severity and serum LDL-cholesterol and non-HDL cholesterol levels in OSA patients.MethodsWe retrospectively evaluated treatment naïve 2361 subjects admitted to the sleep laboratory of a university hospital for polysomnography. All subjects’ lipid profile including total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, and non-HDL-cholesterol were measured.ResultsOut of 2361 patients (mean age 49.6 ± 11.9 years; 68.9% male, apnea-hypopnea index 36.6 ± 28.4/h), 185 (7.8%) had no OSA and 2176 (92.2%) had OSA. Atherogenic dyslipidemia prevalence was high (57–66%) in OSA patients, and especially increased in severe OSA compared to other groups (p < 0.05). Though total and LDL-cholesterol did not differ between those with and without OSA, non-HDL-cholesterol (p = 0.020), and triglycerides (p = 0.001) were higher and HDL-cholesterol levels (p = 0.018) were lower in OSA patients than non-OSA. Non-HDL-cholesterol was significantly correlated with OSA severity (p < 0.001) and hypoxia parameters (p < 0.01), whereas LDL-cholesterol showed no correlation.ConclusionsAtherogenic dyslipidemia is highly prevalent and non-HDL-cholesterol levels are significantly increased, predominantly in severe OSA patients. Non-HDL-cholesterol but not LDL-cholesterol, is significantly correlated with OSA severity and hypoxia parameters. Therefore, it could be better to use non-HDL-cholesterol, which is a guideline recommended target of lipid therapy, as a marker of atherosclerotic cardiovascular risk in OSA patients. 相似文献
8.
9.
目的:探究替米沙坦对冠心病合并糖尿病肾病患者疗效的影响情况。方法:56例探究目标对象均为某院接收的冠心病合并糖尿病肾病患者,挑选时间2018年6月~2019年6月。将"计算机表法"作为分组的参考,分配为参照组(n=28例)执行依那普利治疗,探究组(n=28例)执行替米沙坦治疗。结果:探究组的LVEF、LVEDd、肌酐、24h尿蛋白4项指标与参照组相比,差异有统计学意义(P<0.05);收缩压、舒张压、空腹血糖、餐后2h血糖4项指标与参照组相比,差异没有统计学意义(P>0.05)。结论:冠心病合并糖尿病肾病患者选择替米沙坦治疗后,心室功能的重构以及肾脏预后结局均得到改善,且临床效果比依那普利好,值得借鉴。 相似文献
10.
Leonardo Jönck Staub Roberta Rodolfo Mazzali Biscaro Erikson Kaszubowski Rosemeri Maurici 《The Journal of emergency medicine》2019,56(1):53-69