全文获取类型
收费全文 | 84875篇 |
免费 | 6419篇 |
国内免费 | 1820篇 |
专业分类
耳鼻咽喉 | 724篇 |
儿科学 | 1028篇 |
妇产科学 | 528篇 |
基础医学 | 6380篇 |
口腔科学 | 2724篇 |
临床医学 | 11289篇 |
内科学 | 9625篇 |
皮肤病学 | 986篇 |
神经病学 | 3479篇 |
特种医学 | 14133篇 |
外国民族医学 | 25篇 |
外科学 | 6936篇 |
综合类 | 11806篇 |
现状与发展 | 7篇 |
预防医学 | 4920篇 |
眼科学 | 617篇 |
药学 | 9197篇 |
9篇 | |
中国医学 | 3073篇 |
肿瘤学 | 5628篇 |
出版年
2024年 | 167篇 |
2023年 | 1101篇 |
2022年 | 2060篇 |
2021年 | 2777篇 |
2020年 | 2176篇 |
2019年 | 4508篇 |
2018年 | 4162篇 |
2017年 | 2854篇 |
2016年 | 2457篇 |
2015年 | 2608篇 |
2014年 | 5504篇 |
2013年 | 4754篇 |
2012年 | 4771篇 |
2011年 | 5075篇 |
2010年 | 4786篇 |
2009年 | 5193篇 |
2008年 | 4229篇 |
2007年 | 5104篇 |
2006年 | 4629篇 |
2005年 | 3767篇 |
2004年 | 2446篇 |
2003年 | 2453篇 |
2002年 | 2064篇 |
2001年 | 1788篇 |
2000年 | 1363篇 |
1999年 | 1108篇 |
1998年 | 929篇 |
1997年 | 834篇 |
1996年 | 695篇 |
1995年 | 617篇 |
1994年 | 539篇 |
1993年 | 376篇 |
1992年 | 338篇 |
1991年 | 305篇 |
1990年 | 239篇 |
1989年 | 226篇 |
1988年 | 199篇 |
1987年 | 219篇 |
1986年 | 193篇 |
1985年 | 560篇 |
1984年 | 607篇 |
1983年 | 407篇 |
1982年 | 424篇 |
1981年 | 352篇 |
1980年 | 317篇 |
1979年 | 227篇 |
1978年 | 137篇 |
1977年 | 115篇 |
1976年 | 104篇 |
1974年 | 85篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
41.
Sadahiro Hijikata Igen Hongo Shu-ichi Nakayama Tetsuo Yamaguchi Yoshiyuki Sekikawa Toshihiro Nozato Takashi Ashikaga 《The Canadian journal of cardiology》2019,35(1):104.e9-104.e11
Syphilis is a sexually transmitted disease caused by Treponema pallidum. Syphilitic aortitis might coexist in a dysfunctional aortic valve, but the etiology remains unclear, because microbiological diagnosis is difficult. A 62-year-old man with low-grade fever was diagnosed with aortitis and infective endocarditis, due to Treponema pallidum infection, using polymerase chain reaction analysis. This case suggests that syphilis might cause infective endocarditis. 相似文献
42.
Alexander C. Egbe Rosalyn Adigun Vidhu Anand Collin P. West Victor M. Montori Hassan M. Murad Emmanuel Akintoye Karim Osman Heidi M. Connolly 《The Canadian journal of cardiology》2019,35(12):1784-1790
BackgroundAlthough there are robust data about the pathophysiology and prognostic implications of left ventricular (LV) systolic dysfunction in patients with acquired heart disease, similar prognostic data about LV systolic dysfunction are sparse in the tetralogy of Fallot (TOF) population. The purpose of this study was to perform a meta-analysis of all studies that assessed the relationship between LV ejection fraction (LVEF) and cardiovascular adverse events (CAEs) defined as death, aborted sudden death, or sustained ventricular tachycardia.MethodsWe used random-effects models to calculate hazard ratios (HRs) and 95% confidence intervals (CIs).ResultsOf the 1,809 citations, 7 studies with 2,854 patients (age 28 ± 4 years) were included. During 5.6 ± 3.4 years' follow-up, there were 82 deaths, 17 aborted sudden cardiac deaths, and 56 sustained ventricular tachycardia events. Overall, CAEs occurred in 5.1% (144 patients). As a continuous variable, LVEF was a predictor of CAE (HR 1.29, 95% CI, 1.09-1.53, P = 0.001) per 5% decrease in LVEF. Similarly, LVEF < 40% was also a predictor of CAE (HR 3.22, 95% CI, 2.16-4.80, P < 0.001).ConclusionsLV systolic dysfunction was an independent predictor of CAE, and we observed a 30% increase in the risk of CAE for every 5% decrease in LVEF, and a 3-fold increase in the risk of CAE in patients with LVEF <40% compared with other patients. These findings underscore the importance of incorporating LV systolic function in clinical risk stratification of patients with TOF and the need to explore new treatment options to address this problem. 相似文献
43.
《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
44.
Understanding why persons with human immunodeficiency virus (HIV) have accelerated atherosclerosis and its sequelae, including coronary artery disease (CAD) and myocardial infarction, is necessary to provide appropriate care to a large and aging population with HIV. In this review, we delineate the diverse pathophysiologies underlying HIV-associated CAD and discuss how these are implicated in the clinical manifestations of CAD among persons with HIV. Several factors contribute to HIV-associated CAD, with chronic inflammation and immune activation likely representing the primary drivers. Increased monocyte activation, inflammation, and hyperlipidemia present in chronic HIV infection also mirror the pathophysiology of plaque rupture. Furthermore, mechanisms central to plaque erosion, such as activation of toll-like receptor 2 and formation of neutrophil extracellular traps, are also abundant in HIV. In addition to inflammation and immune activation in general, persons with HIV have a higher prevalence than uninfected persons of traditional cardiovascular risk factors, including dyslipidemia, hypertension, insulin resistance, and tobacco use. Antiretroviral therapies, although clearly necessary for HIV treatment and survival, have had varied effects on CAD, but newer generation regimens have reduced cardiovascular toxicities. From a clinical standpoint, this mix of risk factors is implicated in earlier CAD among persons with HIV than uninfected persons; whether the distribution and underlying plaque content of CAD for persons with HIV differs considerably from uninfected persons has not been definitively studied. Furthermore, the role of cardiovascular risk estimators in HIV remains unclear, as does the role of traditional and emerging therapies; no trials of CAD therapies powered to detect clinical events have been completed among persons with HIV. 相似文献
45.
46.
《药学学报(英文版)》2020,10(7):1294-1308
A great challenge in multi-targeting drug discovery is to identify drug-like lead compounds with therapeutic advantages over single target inhibitors and drug combinations. Inspired by our previous efforts in designing antitumor evodiamine derivatives, herein selective histone deacetylase 1 (HDAC1) and topoisomerase 2 (TOP2) dual inhibitors were successfully identified, which showed potent in vitro and in vivo antitumor potency. Particularly, compound 30a was orally active and possessed excellent in vivo antitumor activity in the HCT116 xenograft model (TGI = 75.2%, 150 mg/kg, p.o.) without significant toxicity, which was more potent than HDAC inhibitor vorinostat, TOP inhibitor evodiamine and their combination. Taken together, this study highlights the therapeutic advantages of evodiamine-based HDAC1/TOP2 dual inhibitors and provides valuable leads for the development of novel multi-targeting antitumor agents. 相似文献
47.
患者男,22岁,无明显诱因咳嗽、痰中带血1周,起初干咳,后咳痰并痰中带血,偶咯出少量暗红色血液;无发热、盗汗、乏力,无胸闷、胸痛及呼吸困难,平素体健,无家族病史。查体:双肺呼吸音稍粗,右肺下叶闻及细湿啰音。胸部增强CT:右肺下叶基底段见片状磨玻璃影,内见直径约8mm粗大供血动脉自腹腔干发出;支气管树分支及肺发育正常,未见隔离肺(图1A^1C)。肺动脉CTA示右下肺基底段动脉部分缺如(图1D),考虑为右下肺异常体动脉供血并周围肺组织肺泡出血可能。 相似文献
48.
目的 探讨类风湿关节炎患者外周血miR-150-5p、细胞因子信号抑制因子1(suppressor of cytokine signaling 1,SOCS1)mRNA的表达及对类风湿关节炎(Rheumatoid Arthritis,RA)疾病诊断、中医证型判断的意义。方法 纳入符合诊断标准的RA患者57例及健康对照组19例,根据《22个专业95个病种中医诊疗方案》有关RA的中医证候诊断标准,判断RA的中医证型。qPCR检测RA患者及健康对照组miR-150-5p、SOCS1mRNA的相对表达水平,同时检测血常规、肝功能、肾功能等常规指标。双荧光素酶分析方法判断两者是否存在靶向关系。统计分析miR-150-5p、SOCS1 mRNA对RA疾病的诊断意义及其与中医证型的相关性。结果 RA患者外周血miR-150-5p的相对表达水平下调,低于正常人群(t = -19.019,P < 0.05);其表达水平随疾病活动度升高,有下降趋势;患者外周血SOCS1 mRNA的相对表达水平上调,低于正常人群(t = 5.333,P < 0.05);其表达水平随疾病活动度升高,有上升趋势。MiR-150-5p与SOCS1 mRNA有靶向结合关系(P < 0.05)。通过AUC曲线比较,miR-150-5p的相对表达水平区分RA的敏感性及特异性分别为98.1%、92.1%(AUC = 0.972,P < 0.05);SOCS1 mRNA的相对表达水平无法区分RA(AUC = 0.472,P > 0.05)。RA患者中miR-150-5p的相对表达水平低于3.06,RA患者风湿痹阻证、寒湿痹阻证的相对风险分别为8.33、250.00(P < 0.05)。结论 miR-150-5p、SOCS1 mRNA在RA患者中有差异性表达,且有靶向结合关系。miR-150-5p可能是RA的疾病诊断及中医风湿痹阻证、寒湿痹阻证证型诊断的潜在生物标志物。 相似文献
49.
50.