全文获取类型
收费全文 | 37626篇 |
免费 | 4279篇 |
国内免费 | 884篇 |
专业分类
耳鼻咽喉 | 126篇 |
儿科学 | 549篇 |
妇产科学 | 1307篇 |
基础医学 | 2131篇 |
口腔科学 | 585篇 |
临床医学 | 9624篇 |
内科学 | 5060篇 |
皮肤病学 | 458篇 |
神经病学 | 1328篇 |
特种医学 | 4442篇 |
外国民族医学 | 8篇 |
外科学 | 3483篇 |
综合类 | 5466篇 |
现状与发展 | 5篇 |
预防医学 | 1730篇 |
眼科学 | 1130篇 |
药学 | 3062篇 |
53篇 | |
中国医学 | 514篇 |
肿瘤学 | 1728篇 |
出版年
2024年 | 40篇 |
2023年 | 652篇 |
2022年 | 933篇 |
2021年 | 1469篇 |
2020年 | 1833篇 |
2019年 | 1663篇 |
2018年 | 1613篇 |
2017年 | 1693篇 |
2016年 | 1664篇 |
2015年 | 1747篇 |
2014年 | 2887篇 |
2013年 | 2848篇 |
2012年 | 2210篇 |
2011年 | 2276篇 |
2010年 | 1766篇 |
2009年 | 1752篇 |
2008年 | 1783篇 |
2007年 | 1872篇 |
2006年 | 1659篇 |
2005年 | 1271篇 |
2004年 | 1127篇 |
2003年 | 1114篇 |
2002年 | 903篇 |
2001年 | 779篇 |
2000年 | 548篇 |
1999年 | 550篇 |
1998年 | 498篇 |
1997年 | 489篇 |
1996年 | 371篇 |
1995年 | 345篇 |
1994年 | 340篇 |
1993年 | 284篇 |
1992年 | 230篇 |
1991年 | 200篇 |
1990年 | 169篇 |
1989年 | 145篇 |
1988年 | 138篇 |
1987年 | 123篇 |
1986年 | 109篇 |
1985年 | 164篇 |
1984年 | 125篇 |
1983年 | 56篇 |
1982年 | 96篇 |
1981年 | 58篇 |
1980年 | 49篇 |
1979年 | 36篇 |
1978年 | 36篇 |
1977年 | 29篇 |
1976年 | 23篇 |
1973年 | 11篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
21.
目的 采用Meta分析对比四维子宫输卵管超声造影(4D-HyCoSy)与子宫输卵管造影(HSG)评估输卵管通畅性的效能。方法 系统搜索PubMed、Cochrane Library、Embase、Web of Science、中国生物医学文献数据库、中国知网、万方医学网及维普数据库中建库至今有关4D-HyCoSy和/或HSG评估输卵管通畅性的文献。由2名研究人员依据纳入标准和排除标准筛选文献并提取信息;分别计算4D-HyCoSy和HSG评估输卵管通畅性的合并敏感度(SEN)、特异度(SPE)及诊断比值比(DOR),绘制综合受试者工作特征(SROC)曲线,获得曲线下面积(AUC),并以Medcalc 19.1.1统计软件比较AUC。结果 最终纳入19篇文献、1 358例疑似输卵管因素导致不孕患者,其中4篇同时采用4D-HyCoSy及HSG评估输卵管通畅性,10篇仅以4D-HyCoSy评估,5篇仅以HSG评估。Meta分析结果显示,4D-HyCoSy评估输卵管通畅性的合并SEN、SPE及DOR分别为0.92[95%CI(0.91,0.94)]、0.91[95%CI(0.89,0.93)]及115.06[95%CI(54.23,224.10)];HSG评估输卵管通畅性的合并SEN、SPE及DOR分别为0.84[95%CI(0.81,0.87)]、0.80[95%CI(0.76,0.83)]及28.64[95%CI(10.08,81.35)]。4D-HyCoSy评估输卵管通畅性的AUC为0.98[95%CI(0.96,0.99)],HSG为0.93[95%CI(0.90,0.95)],差异有统计学意义(Z=6.97,P<0.01)。结论 4D-HyCoSy评估输卵管通畅性的效能高于HSG。 相似文献
22.
23.
24.
Ashok Garg Deepak Agrawal Deepika Mishra Gyarsi Lal Sharma 《Echocardiography (Mount Kisco, N.Y.)》2019,36(7):1421-1422
Raghib syndrome is a rare developmental complex consisting of termination of the left superior vena cava in the left atrium, absence of the coronary sinus, and an atrial septal defect commonly located at the posterior‐inferior angle of the atrial septum. This complex was considered unique to Raghib syndrome; however, cases with a normal atrial septum have been reported where the orifice of the unroofed coronary sinus functions as the inter‐atrial communication. Our patient demonstrated an isolated persistent left superior vena cava draining into the left atrium through unroofed coronary sinus and presence of ostium primum atrial septal defect. 相似文献
25.
26.
27.
28.
《Journal of Cardiovascular Computed Tomography》2019,13(5):254-260
Invasive coronary plaque imaging such as intravascular ultrasound and optical coherence tomography has been widely used to observe culprit or non-culprit coronary atherosclerosis, as well as optimize stent sizing, apposition and deployment. Coronary computed tomographic angiography (CTA) is non-invasively available to assess coronary artery disease (CAD) and has become an appropriate strategy to evaluate patients with suspected CAD. Given recent technologies, semi-automated plaque software is available to identify coronary plaque stenosis, volume and characteristics and potentially allows to be used for the assessment of more details of plaque information, progression and future risk as a surrogate tool of the invasive imaging modalities. This review article aims to focus on various evidence in coronary plaque imaging by coronary CTA and describes how accurate coronary CTA can classify coronary atherosclerosis. 相似文献
29.
《Journal l'Association canadienne des radiologistes》2019,70(3):226-232
In 2017, the Canadian Association of Radiologists issued a clinical practice guideline (CPG) regarding the use of gadolinium-based contrast agents (GBCAs) in patients with acute kidney injury (AKI), chronic kidney disease (CKD), or on dialysis due to mounting evidence indicating that nephrogenic systemic fibrosis (NSF) occurs with extreme rarity or not at all when using Group II GBCAs or the Group III GBCA gadoxetic acid (compared to first generation Group I linear GBCAs). One of the goals of the work group was to re-evaluate the CPG after 24 months to determine the effect of more liberal use of GBCA on reported cases of NSF in patients with AKI, CKD Stage 4 or 5 (estimated glomerular filtration rate [eGFR] < 30 mL/min/1.73 m2), or those that are dialysis-dependent. A comprehensive review of the literature was conducted by a subcommittee of the initial CPG panel between the dates of January 1, 2017-December 31, 2018 to identify new unconfounded cases of NSF linked to Group II or Group III GBCAs and an updated CPG developed. To our knowledge, when using a Group II or Group III GBCA between 2017-2018, only a single unconfounded case report of a fibrosing dermopathy has been reported in a patient who received gadobenate dimeglumine with Stage 2 CKD. No other unconfounded cases of NSF have been reported with Group II or III agents in during this timeframe. The subcommittee concluded that the main recommendations from the 2017 CPG should remain unaltered, but agreed that screening for renal disease in the outpatient setting is no longer justifiable, cost-effective or recommended. Patients on hemodialysis (HD) should, however, be identified prior to GBCA administration to arrange timely HD to optimize gadolinium clearance, although there remains no evidence that HD reduces the risk of NSF. When administering Group II or III GBCAs to patients with AKI, on dialysis or with severe CKD, informed consent relating to NSF is also no longer explicitly recommended. 相似文献
30.