全文获取类型
收费全文 | 34148篇 |
免费 | 2298篇 |
国内免费 | 1357篇 |
专业分类
耳鼻咽喉 | 127篇 |
儿科学 | 304篇 |
妇产科学 | 134篇 |
基础医学 | 1894篇 |
口腔科学 | 148篇 |
临床医学 | 4955篇 |
内科学 | 12550篇 |
皮肤病学 | 64篇 |
神经病学 | 366篇 |
特种医学 | 1861篇 |
外科学 | 2215篇 |
综合类 | 7008篇 |
现状与发展 | 1篇 |
预防医学 | 975篇 |
眼科学 | 79篇 |
药学 | 3248篇 |
26篇 | |
中国医学 | 1588篇 |
肿瘤学 | 260篇 |
出版年
2024年 | 81篇 |
2023年 | 486篇 |
2022年 | 933篇 |
2021年 | 1320篇 |
2020年 | 1209篇 |
2019年 | 1047篇 |
2018年 | 1042篇 |
2017年 | 906篇 |
2016年 | 943篇 |
2015年 | 969篇 |
2014年 | 2057篇 |
2013年 | 2186篇 |
2012年 | 1655篇 |
2011年 | 1967篇 |
2010年 | 1573篇 |
2009年 | 1551篇 |
2008年 | 1622篇 |
2007年 | 1730篇 |
2006年 | 1678篇 |
2005年 | 1412篇 |
2004年 | 1220篇 |
2003年 | 1077篇 |
2002年 | 923篇 |
2001年 | 985篇 |
2000年 | 820篇 |
1999年 | 748篇 |
1998年 | 668篇 |
1997年 | 648篇 |
1996年 | 495篇 |
1995年 | 468篇 |
1994年 | 457篇 |
1993年 | 368篇 |
1992年 | 313篇 |
1991年 | 287篇 |
1990年 | 235篇 |
1989年 | 204篇 |
1988年 | 211篇 |
1987年 | 189篇 |
1986年 | 161篇 |
1985年 | 193篇 |
1984年 | 173篇 |
1983年 | 97篇 |
1982年 | 113篇 |
1981年 | 100篇 |
1980年 | 71篇 |
1979年 | 57篇 |
1978年 | 43篇 |
1977年 | 43篇 |
1976年 | 24篇 |
1974年 | 14篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Jorge A. Wong David Conen Isabelle C. Van Gelder William F. McIntyre Harry J. Crijns Jia Wang Michael R. Gold Stefan H. Hohnloser C.P. Lau Alessandro Capucci Gianluca Botto Gerian Grönefeld Carsten W. Israel Stuart J. Connolly Jeff S. Healey 《Journal of the American College of Cardiology》2018,71(23):2603-2611
Background
Long-term continuous monitoring detects short-lasting, subclinical atrial fibrillation (SCAF) in approximately one-third of older individuals with cardiovascular conditions. The relationship between SCAF, its progression, and the development of heart failure (HF) is unclear.Objectives
This study examined the relationship between progression from shorter to longer SCAF episodes and HF hospitalization.Methods
Subjects in ASSERT (Asymptomatic Atrial Fibrillation and Stroke Evaluation in Pacemaker Patients and the Atrial Fibrillation Reduction Atrial Pacing Trial) were ≥65 years old, had history of hypertension, no prior clinical AF, and an implanted pacemaker or defibrillator. We examined patients whose longest SCAF episode during the first year after enrollment was >6 min but ≤24 h (n = 415). Using time-dependent Cox models, we evaluated the relationship between subsequent development of SCAF >24 h or clinical AF and HF hospitalization.Results
Over a mean follow-up of 2 years, 65 patients (15.7%) progressed to having SCAF episodes >24 h or clinical AF (incidence 8.8% per year). Older age, greater body mass index, and longer SCAF duration within the first year were independent predictors of SCAF progression. The rate of HF hospitalization among patients with SCAF progression was 8.9% per year compared with 2.5% per year for those without progression. After multivariable adjustment, SCAF progression was independently associated with HF hospitalization (hazard ratio [HR]: 4.58; 95% confidence interval [CI]: 1.64 to 12.80; p = 0.004). Similar results were observed when we excluded patients with prior history of HF (HR: 7.06; 95% CI: 1.82 to 27.30; p = 0.005) or when SCAF progression was defined as development of SCAF >24 h alone (HR: 3.68; 95% CI: 1.27 to 10.70; p = 0.016).Conclusions
In patients with a pacemaker or defibrillator, SCAF progression was strongly associated with HF hospitalization. 相似文献992.
目的研究抑郁对于心肌梗死恢复期患者心率震荡变化的影响。方法通过动态心电图对比观察62例心肌梗死后恢复期出现抑郁表现的患者(抑郁组),以及同等例数心肌梗死后无抑郁表现的患者(无抑郁组)和非器质性心脏病疾患(对照组)的震荡初始(T0)和震荡斜率(Ts)的变化。结果抑郁组TO比无抑郁组、对照组均明显升高(2.24±1.82VS.1.45±2.21VS.-0.25±1.42,P〈0.05),而TS比对照组明显降低(1.90±2.14vs.3.79±2.22,P〈0.05)。结论有抑郁表现的心肌梗死恢复期患者的心率震荡异常更明显。 相似文献
993.
Kazuo Umemura Shinji Watanabe Kazunao Kondo Hisakuni Hashimoto Mitsuyoshi Nakashima 《Atherosclerosis》1997,130(1-2):11-16
The inhibitory effect of prostaglandin E1, which has an anti-platelet action and a vasodilating action via intracellular cyclic AMP elevation, was studied on intimal thickening in the rat femoral artery. A segment of the femoral artery was occluded by a platelet and fibrin-rich thrombus due to photochemical reaction between systemically administered Rose Bengal and transluminal green light which causes endothelial injury followed by platelet adhesion and aggregation at the site of photochemical reaction. Three weeks after endothelial injury, intimal thickening occurred at the irradiated site. Prostaglandin E1 (0.3 μg/kg per min), administered as a continuous infusion 10 min before photochemical reaction significantly (P<0.05) prolonged the time to occlusion of the femoral artery. In a separate experiment, prostaglandin E1 (0.3 μg/kg per min) administered as a continuous infusion for 7 days just after endothelial injury significantly (P<0.05) inhibited intimal thickening compared with a control group. In cultured rat-derived vascular smooth muscle cells, prostaglandin E1 produced concentration-dependent inhibition of migration and proliferation, stimulated by platelet-derived growth factor. These results suggest that prostaglandin E1 may be effective in preventing vascular restenosis after vascular surgery and angioplasty. 相似文献
994.
Acute coronary syndrome (ACS) remains a major burden on morbidity and mortality in the United States. Medical professionals and students often use the mnemonic ‘MONA’ (morphine, oxygen, nitroglycerin and aspirin) to recall treatments for ACS; however, this list of therapies is outdated. We provide a historical perspective on ‘MONA,’ attempt to uncover its origin in the medical literature, and demonstrate the myriad changes that have occurred over the last 50 years of ACS management. We have developed a novel mnemonic, ‘THROMBINS2’ (thienopyridines, heparin/enoxaparin, renin–angiotensin system blockers, oxygen, morphine, beta blocker, intervention, nitroglycerin, statin/salicylate) to help bedside clinicians recall all the elements of contemporary ACS management. We demonstrate the mortality benefit for each component of contemporary ACS management, correlating the continued improvement with historical data on mortality after myocardial infarction. We encourage providers to utilize this mnemonic to explore options and guide treatments in ACS patients. 相似文献
995.
996.
目的探讨预见性护理在老年重症心肌梗死患者中的应用价值。方法将56例老年重症心肌梗死患者随机分为研究组和对照组各28例。对照组采用常规护理,即不良心理、并发症、便秘等均在发生后再对症进行护理;研究组采用预见性护理,在各类心理和生理不良反应出现前,于患者入院时起,即密切监视,预防不良心理和各类并发症的发生。结果研究组患者并发症发生率、便秘发生率和病死率均显著低于对照组,差异具有统计学意义(P0.05)。研究组患者抑郁评分和焦虑评分均极显著低于对照组,说明研究组患者的心理状态优于对照组,差异具有统计学意义(P0.01)。结论预见性护理对老年重症心肌梗死患者具有较好的应用价值,可降低并发症发生率、便秘发生率和病死率,并有利于患者保持良好的心态。 相似文献
997.
目的探讨研究非体外循环冠状动脉搭桥术(OPCAB)的临床疗效。方法选取符合标准的52例患者并进行OPCAB,探讨研究使用该手术方法时,患者在术中的生理指标情况、术后患者的心肌酶指标变化情况以及术后患者的心脏功能的变化情况。并选取常规体外循环下冠状动脉搭桥术(cCABG)组48例作为对照。结果 52例患者均手术成功。所有患者进行搭桥1~6支,平均(3.1±1.7)支;手术时间(1.8~6.7)h,平均手术时间(3.3±1.5)h。在手术过程中,在吻合回旋支时,患者的血氧分压(PaO2)、心率(HR)和平均血压(MAP)与麻醉前相比,差异有统计学意义(P0.05)。在术后1d,患者的肌酸激酶、肌酸激酶同工酶与天门冬氨酸氨基转移酶水平均明显高于手术前(P0.05),而乳酸脱氢酶与术前相比差异无统计学意义(P0.05)。在术后1周,患者肌酸激酶、肌酸激酶同工酶与天门冬氨酸氨基转移酶水平均恢复到正常水平,与术前相比差异无统计学意义(P0.05);而乳酸脱氢酶水平明显高于术前(P0.05)。患者在术后3月的射血分数为(47.6±6.9)%,明显高于术前的(39.1±5.1)%(P0.05)。OPCAB组的ICU治疗时间、辅助呼吸时间、心电监测时间、使用抗生素时间、进食时间、坐起时间与留置引流管时间均明显小于cCABG组(P0.05)。OPCAB组患者的总并发症发生率明显低于cCABG组(P0.05)。结论采用OPCAB进行治疗能够很好地降低患者心肌缺血、免疫损伤、再灌注损伤等情况的发生,有效地保护了患者的心脏,促进患者的康复。OPCAB值得在临床上进一步推广使用。 相似文献
998.
Andrei Roman Carmen Georgiu Dan Nicolau Wissam Sabha Miruna Surariu Dorel Precup 《Annals of thoracic and cardiovascular surgery》2015,21(5):492-495
The hydatid disease is a zoonosis endemic to rural countries, such as those in the Mediterranean region, South America, North Africa, Central Asia and China. Hydatid cysts commonly affect liver and lungs, but less than 100 cases of costal hydatidosis have been reported in the literature. While diagnosis of the disease in commonly affected organs is relatively easy, uncommon locations can prove to be challenging as is the case with costal hydatidosis. Imaging techniques can suggest the diagnosis, but sometimes it remains uncertain until surgery. The treatment is surgical, assisted by long-time Albendazole chemotherapy. We present a rare case of costal hydatidosis, the first one to be reported in Romania according to our review of the literature. 相似文献
999.
1000.
目的 探讨阴道前壁“桥”式缝合术治疗阴道前壁脱垂的疗效.方法 回顾性分析自2007年7月至2013年5月,采用手术治疗阴道前壁脱垂58例患者的临床资料,其中阴道前壁“桥”式缝合术30例,传统的阴道前壁修补术28例;比较两种术式的近期疗效.结果 阴道前壁“桥”式缝合术的手术时间为(21.50±3.80) min,术中出血量为(30.00 ±3.20)ml,术后复发率为3.33%,与传统术式的手术时间(48.50±3.50) min、术中出血量(74.00±5.60) ml、术后复发率14.29%进行比较,其差异均有统计学意义(P<0.05).结论 与传统术式比较,“桥”式缝合术治疗阴道前壁脱垂的手术时间短,术中出血少,术后复发率低,近期疗效满意. 相似文献