全文获取类型
收费全文 | 79452篇 |
免费 | 3340篇 |
国内免费 | 1237篇 |
专业分类
耳鼻咽喉 | 981篇 |
儿科学 | 5824篇 |
妇产科学 | 1101篇 |
基础医学 | 5650篇 |
口腔科学 | 1569篇 |
临床医学 | 6450篇 |
内科学 | 14946篇 |
皮肤病学 | 607篇 |
神经病学 | 6308篇 |
特种医学 | 1640篇 |
外国民族医学 | 1篇 |
外科学 | 9375篇 |
综合类 | 7550篇 |
一般理论 | 1篇 |
预防医学 | 9179篇 |
眼科学 | 764篇 |
药学 | 7326篇 |
50篇 | |
中国医学 | 2940篇 |
肿瘤学 | 1767篇 |
出版年
2024年 | 161篇 |
2023年 | 1286篇 |
2022年 | 2321篇 |
2021年 | 3316篇 |
2020年 | 2520篇 |
2019年 | 4522篇 |
2018年 | 3738篇 |
2017年 | 2829篇 |
2016年 | 2112篇 |
2015年 | 1841篇 |
2014年 | 4349篇 |
2013年 | 4077篇 |
2012年 | 3688篇 |
2011年 | 4141篇 |
2010年 | 3104篇 |
2009年 | 2992篇 |
2008年 | 2970篇 |
2007年 | 2849篇 |
2006年 | 2263篇 |
2005年 | 1821篇 |
2004年 | 1421篇 |
2003年 | 1157篇 |
2002年 | 886篇 |
2001年 | 813篇 |
2000年 | 709篇 |
1999年 | 550篇 |
1998年 | 464篇 |
1997年 | 401篇 |
1996年 | 355篇 |
1995年 | 325篇 |
1994年 | 334篇 |
1993年 | 248篇 |
1992年 | 199篇 |
1991年 | 180篇 |
1990年 | 164篇 |
1989年 | 163篇 |
1988年 | 128篇 |
1985年 | 1511篇 |
1984年 | 2526篇 |
1983年 | 2318篇 |
1982年 | 1751篇 |
1981年 | 1828篇 |
1980年 | 1525篇 |
1979年 | 1342篇 |
1978年 | 1165篇 |
1977年 | 676篇 |
1976年 | 1127篇 |
1975年 | 987篇 |
1974年 | 821篇 |
1973年 | 788篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
Conall T. Morgan Brigitte Mueller Varsha Thakur Vitor Guerra Callaghan Jull Luc Mertens Mark Friedberg Fraser Golding Mike Seed Steven E.S. Miner Edgar T. Jaeggi Cedric Manlhiot Lynne E. Nield 《The Canadian journal of cardiology》2019,35(4):453-461
Background
The purpose of the study was to evaluate the association between fetal echocardiographic measurements and the need for intervention (primary coarctation repair, staged coarctation repair, or catheter intervention) in prenatally diagnosed coarctation of the aorta.Methods
A single-centre retrospective cohort study (2005-2015) of 107 fetuses diagnosed with suspected coarctation of the aorta in the setting of an apex-forming left ventricle and antegrade flow across the mitral and aortic valves.Results
Median gestational age at diagnosis was 32 weeks (interquartile range, 23-35 weeks). Fifty-six (52%) did not require any neonatal intervention, 51 patients (48%) underwent a biventricular repair. In univariable analysis, an increase in ascending aorta (AAo) peak Doppler flow velocity (odds ratio [OR], 1.40 [95% confidence interval [CI], 1.05-1.91] per 20 cm/s; P = 0.03) was associated with intervention. No intervention was associated with larger isthmus size (OR, 0.23; P < 0.001), transverse arch diameter (OR, 0.23; P < 0.001), and aortic (OR, 0.72; P = 0.02), mitral (OR, 0.58; P = 0.001), and AAo (OR, 0.53; P < 0.001) z-scores. In multivariable analysis, higher peak AAo Doppler (OR, 2.51 [95% CI, 1.54-4.58] per 20 cm/s; P = 0.001) and younger gestational age at diagnosis (OR, 0.81 [95% CI, 0.70-0.93] per week; P = 0.005) were associated with intervention, whereas a higher AAo z-score (OR, 0.65 [95% CI, 0.43-0.94] per z; P = 0.029) and transverse arch dimension (OR, 0.44 [95% CI, 0.18-0.97]; P = 0.05) decreased the risk of intervention.Conclusions
In prenatally suspected coarctation, the variables associated with intervention comprised smaller AAo and transverse arch size, earlier gestational age at diagnosis, and the additional finding of a higher peak AAo Doppler. 相似文献12.
目的 探讨电针复合靶控输注(Target Controlled Infusion, TCI)在单肺通气食管癌开胸手术麻醉中的应用价值。方法 选取于我院拟行单肺通气食管癌开胸切除手术患者60例作为研究对象。随机将其分为试验组与对照组,对照组30例采取气管插管全麻及TCI靶控输注维持麻醉深度,试验组30例则在对照组方案基础上辅助电针麻醉,记录两组患者手术麻醉时间、药物用量、苏醒时间、并发症;以及术前(TⅠ)、插管前即刻(TⅡ)、插管后1 min(TⅢ)、切皮即刻(TⅣ)、去骨时(TⅤ)、拔管即刻(TⅥ)时平均动脉压(MAP)、平均心率(HR)、BIS值;术前、术后1天、术后3天简易智能精神状态检查量表(MMSE);并于麻醉诱导前(T0)、手术开始2 h(T1)、术后1天(T2)、术后3天(T3)时抽取患者外周静脉血检测IL-1β、IL-6、IL-10、TNF-α浓度。结果 试验组手术用时、麻醉时间略低于对照组,但差异无统计学意义(P>0.05),试验组异丙酚、舒芬太尼用量以及苏醒时间均明显低于对照组(P<0.05);TⅡ时两组平均动脉压(Mean Arterial Pressure, MAP)、心率(Heartrate, HR)较术前明显降低,且试验组MAP明显低于对照组(P<0.05),但两组TⅡ时HR比较无显著差异(P>0.05);TⅢ、TⅥ时对照组MAP、HR明显高于TⅠ时,而试验组MAP、HR与TⅠ比较无显著差异(P>0.05)。术后1天、3天试验组简易智能精神状态检查量表(Mini-Mental State Examination, MMSE)评分低于对照组,有显著性差异(P<0.05)。T1、T2、T3时试验组白介素-1β(IL-1β)、白介素-6(IL-6)、肿瘤坏死因子(Tumor Necrosis Factor-α, TNF-α)水平明显低于对照组(P<0.05),白介素-10(IL-10)水平明显高于对照组(P<0.05)。结论 采用电针复合TCI靶控输注麻醉方案可有效提升单肺通气食管癌开胸手术麻醉效果,能够降低患者术后认知功能障碍发生风险。 相似文献
13.
14.
Mariko Morimoto 《Health marketing quarterly》2020,37(2):108-123
AbstractThis research explores how the level of consumers’ need for cognition (NFC) is associated with celebrity endorser credibility and examines its effects on advertising-related attitudes. A 3 (endorser types: actor/actress, athlete, TV personality/talent) × 2 (endorser’s gender) factorial experiment with 435 Japanese consumers was conducted. Concerning Japanese OTC drug advertising, lower NFC individuals perceived celebrity endorsers as more credible in comparison to higher NFC individuals. The main effects of NFC and endorser type on endorser credibility existed; however, no interaction between the two variables was found. The endorser type had an influence on attitudes toward ads and the advertised brand. 相似文献
15.
16.
《Sleep medicine》2020
BackgroundThere is limited information about the long-term outcome of obstructive sleep apnea (OSA) diagnosed in children and adolescents for educational and social factors. Here, we estimate the long-term socioeconomic outcome and health care costs of OSA.MethodsThe historical case-control cohort study included Danish individuals with OSA diagnosed in childhood or adolescence between 1994 and 2015. Health care costs and socioeconomic data were obtained from nationwide administrative and health registers. A total of 5419 were diagnosed during this period; of these we traced 1004 patients who we compared with 4085 controls (mean index age, 10.2 years; Standard Deviation (SD), 5.6 years) until the age of 20 years. Controls were matched for age, gender, and residency.ResultsComparing the OSA patient and control groups at age 20 years we found: 1) lower parental educational level; 2) significantly lower educational level also after adjustment for parental educational level; 3) lower school grade-point averages; 4) lower employment rate and lower income, which was not fully compensated when transfer payments were considered; and 5) patients' initial health care costs were higher due to higher morbidity. Patients showed higher mortality rates than controls (Hazard Ratio (HR) = 7.63, 95% CI = 4.87–11.95, P < 0.001).ConclusionsOSA in children and adolescent is associated with a significant influence on morbidity, mortality, educational level, grading, social outcome, and welfare consequences. 相似文献
17.
18.
《Journal of Clinical Orthopaedics and Trauma》2021,12(6):976-982
ObjectiveMultiple treatment options for acetabular fractures in geriatric patients exist. However, no large-scale studies have reported the outcomes of acute total hip arthroplasty (THA) in this patient population. We systematically evaluated all available evidence to characterize clinical outcomes, complications, and revisions of acute THA for acetabular fractures in geriatric patients.MethodsMeta-analysis of 21 studies of 430 acetabular fractures with mean follow-up of 44 months (range, 17−97 months). Two independent researchers searched and evaluated the databases of Ovid, Embase, and United States National Library of Medicine using a Boolean search string up to December 2019. Population demographics and complications, including presence of heterotopic ossification (HO), dislocation, infection, revision rate, neurological deficits, and venous thromboembolic event (VTE), were recorded and analyzed.ResultsWeighted mean Harris Hip Score was 83.3 points, and 20% of the patients had reported complications. The most common complication was HO, with a rate of 19.5%. Brooker grade III and IV HO rates were lower at 6.8%. Hip dislocation occurred at a rate of 6.1%, 4.1% of patients developed VTE, deep infection occurred in 3.8%, and neurological complications occurred in 1.9%. Although the revision rate was described in most studies, we were unable to perform a survival analysis because the time to each revision was described in only a few studies. The revision rate was 4.3%.ConclusionsAcute THA is a viable option for treatment of acetabular fracture and can result in acceptable clinical outcomes and survivorship rates in older patients but with an associated complication rate of approximately 20%. Considering the limited treatment options, THA might be a viable alternative for appropriately selected patients. 相似文献
19.
目的探讨脾大部切除加断流术治疗小儿门静脉高压症的临床疗效。方法对16例确诊为门静脉高压症的患儿行脾大部切除加断流术。随访患儿恢复情况。结果16例患儿手术顺利,恢复良好,无死亡病例。无再发消化道出血、脾功能亢进表现,无脾切除术后凶险感染出现。结论保留脾脏的脾大部切除加断流术是治疗小儿门静脉高压症一种较好的手术方法。 相似文献
20.
YOSHINORI MORITA NOBUO AOYAMA DAISUKE SHIRASAKA MASATERU FUKUDA MASATO KASUGA 《Digestive endoscopy》2003,15(Z1):S12-S14
In Kobe University Hospital, a new method for endoscopic mucosal resection (EMR) using insulated‐tip electrosurgical knife (IT‐EMR) for early gastric cancer (EGC) was introduced from November 2001. To achieve an effective and safe IT‐EMR procedure, we use a high‐frequency surgical unit for cutting and coagulation (ERBOTOM ICC 200) with automatically controlled cutting mode (ENDOCUT). In this study, we show not only our results of IT‐EMR for EGC in comparison with those of the conventional strip biopsy method, but also the optimal conditions for the apparatus of a high‐frequency surgical unit to prevent complications such as bleeding and perforation. 相似文献