全文获取类型
收费全文 | 13407篇 |
免费 | 384篇 |
国内免费 | 128篇 |
专业分类
耳鼻咽喉 | 199篇 |
儿科学 | 308篇 |
妇产科学 | 202篇 |
基础医学 | 667篇 |
口腔科学 | 288篇 |
临床医学 | 1116篇 |
内科学 | 4001篇 |
皮肤病学 | 301篇 |
神经病学 | 606篇 |
特种医学 | 706篇 |
外科学 | 2151篇 |
综合类 | 758篇 |
预防医学 | 1071篇 |
眼科学 | 470篇 |
药学 | 606篇 |
1篇 | |
中国医学 | 78篇 |
肿瘤学 | 390篇 |
出版年
2024年 | 17篇 |
2023年 | 492篇 |
2022年 | 647篇 |
2021年 | 1047篇 |
2020年 | 913篇 |
2019年 | 1062篇 |
2018年 | 972篇 |
2017年 | 517篇 |
2016年 | 262篇 |
2015年 | 292篇 |
2014年 | 946篇 |
2013年 | 662篇 |
2012年 | 478篇 |
2011年 | 561篇 |
2010年 | 464篇 |
2009年 | 526篇 |
2008年 | 569篇 |
2007年 | 602篇 |
2006年 | 376篇 |
2005年 | 349篇 |
2004年 | 287篇 |
2003年 | 234篇 |
2002年 | 202篇 |
2001年 | 130篇 |
2000年 | 143篇 |
1999年 | 159篇 |
1998年 | 119篇 |
1997年 | 116篇 |
1996年 | 86篇 |
1995年 | 73篇 |
1994年 | 62篇 |
1993年 | 42篇 |
1992年 | 71篇 |
1991年 | 46篇 |
1990年 | 44篇 |
1989年 | 29篇 |
1988年 | 35篇 |
1987年 | 18篇 |
1986年 | 29篇 |
1985年 | 37篇 |
1984年 | 26篇 |
1983年 | 24篇 |
1982年 | 26篇 |
1981年 | 29篇 |
1980年 | 19篇 |
1979年 | 20篇 |
1978年 | 13篇 |
1977年 | 14篇 |
1976年 | 8篇 |
1973年 | 8篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
《Journal of vascular and interventional radiology : JVIR》2022,33(4):359-367.e8
PurposeTo review and to compare indirectly the outcomes of minimally invasive therapies for the treatment of lower urinary tract symptoms secondary to benign prostatic hyperplasia.Materials and MethodsA literature search via Medline and Cochrane Central databases was completed for randomized control studies published between January 2000 to April 2020 for the following therapies: Rezum, Urolift, Aquablation, and prostatic artery embolization (PAE). Data on the following variables were included: International prostate symptom score (IPSS), maximum urinary flow rate, quality of life, and postvoid residual (PVR). Standard mean differences between treatments were compared through a meta-analysis using transurethral resection of the prostate (TURP) to assess differences in treatment effect.ResultsThere was no significant difference in outcomes between therapies for IPSS at the 3, 6, and 12-month follow ups. Although outcomes for Rezum were only available out to 3 months, there were no consistently significant differences in outcomes when comparing Aquablation versus PAE versus Rezum. TURP PVR was significantly better than Urolift at 3, 6, and 12 months. No significant differences in minor or major adverse events were noted.ConclusionAlthough significant differences in outcomes were limited, Aquablation and PAE were the most durable at 12 months. PAE has been well studied on multiple randomized control trials with minimal adverse events while Aquablation has limited high quality data and has been associated with bleeding-related complications. 相似文献
2.
《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
3.
4.
5.
《Diagnostic and interventional imaging》2020,101(9):555-564
PurposeThe purpose of this study was to determine whether computed tomography (CT)-based machine learning of radiomics features could help distinguish autoimmune pancreatitis (AIP) from pancreatic ductal adenocarcinoma (PDAC).Materials and MethodsEighty-nine patients with AIP (65 men, 24 women; mean age, 59.7 ± 13.9 [SD] years; range: 21–83 years) and 93 patients with PDAC (68 men, 25 women; mean age, 60.1 ± 12.3 [SD] years; range: 36–86 years) were retrospectively included. All patients had dedicated dual-phase pancreatic protocol CT between 2004 and 2018. Thin-slice images (0.75/0.5 mm thickness/increment) were compared with thick-slices images (3 or 5 mm thickness/increment). Pancreatic regions involved by PDAC or AIP (areas of enlargement, altered enhancement, effacement of pancreatic duct) as well as uninvolved parenchyma were segmented as three-dimensional volumes. Four hundred and thirty-one radiomics features were extracted and a random forest was used to distinguish AIP from PDAC. CT data of 60 AIP and 60 PDAC patients were used for training and those of 29 AIP and 33 PDAC independent patients were used for testing.ResultsThe pancreas was diffusely involved in 37 (37/89; 41.6%) patients with AIP and not diffusely in 52 (52/89; 58.4%) patients. Using machine learning, 95.2% (59/62; 95% confidence interval [CI]: 89.8–100%), 83.9% (52:67; 95% CI: 74.7–93.0%) and 77.4% (48/62; 95% CI: 67.0–87.8%) of the 62 test patients were correctly classified as either having PDAC or AIP with thin-slice venous phase, thin-slice arterial phase, and thick-slice venous phase CT, respectively. Three of the 29 patients with AIP (3/29; 10.3%) were incorrectly classified as having PDAC but all 33 patients with PDAC (33/33; 100%) were correctly classified with thin-slice venous phase with 89.7% sensitivity (26/29; 95% CI: 78.6–100%) and 100% specificity (33/33; 95% CI: 93–100%) for the diagnosis of AIP, 95.2% accuracy (59/62; 95% CI: 89.8–100%) and area under the curve of 0.975 (95% CI: 0.936–1.0).ConclusionsRadiomic features help differentiate AIP from PDAC with an overall accuracy of 95.2%. 相似文献
6.
Injury to the distal biceps occurs in certain high risk groups. Anatomical continuity of the lacertus fibrosus has bearing on the extent of retraction of the torn tendon stump. The objective of clinical and imaging evaluation is to discriminate between tendinosis, partial tear, acute complete tear and chronic complete tear. A complete tear of the distal biceps tendon can be diagnosed clinically with the Hook test. The traditional Hook test and the resisted Hook test are useful clinical tests. Though x-rays are routinely done, MRI remains the investigation of choice. Non-operative treatment has a role in selected patients with partial tear or patients with complete tear who have low functional demands. Operative treatment is the recommended treatment for complete tear of the distal biceps and is associated with good functional outcome and patient satisfaction. 相似文献
7.
8.
《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
9.
Various techniques of reconstruction of deformed Charcot hindfoot using different internal fixation devices have been described in the literature. We present our surgical technique using specific principles that has resulted in improved outcomes to allow correction of deformity, obtain stability and allow progression to weightbearing in orthotic shoes. We describe our preoperative evaluation, planning and surgical timing. We also hope to share some technical pearls and details on the finer points to achieve a satisfactory correction and reduce the learning curve. 相似文献
10.