全文获取类型
收费全文 | 4020539篇 |
免费 | 284172篇 |
国内免费 | 9064篇 |
专业分类
耳鼻咽喉 | 55861篇 |
儿科学 | 131687篇 |
妇产科学 | 110607篇 |
基础医学 | 573527篇 |
口腔科学 | 112019篇 |
临床医学 | 370129篇 |
内科学 | 775614篇 |
皮肤病学 | 92902篇 |
神经病学 | 325787篇 |
特种医学 | 152083篇 |
外国民族医学 | 1141篇 |
外科学 | 600536篇 |
综合类 | 83650篇 |
现状与发展 | 15篇 |
一般理论 | 1603篇 |
预防医学 | 314667篇 |
眼科学 | 93668篇 |
药学 | 296174篇 |
16篇 | |
中国医学 | 7855篇 |
肿瘤学 | 214234篇 |
出版年
2019年 | 32269篇 |
2018年 | 44631篇 |
2017年 | 33827篇 |
2016年 | 38896篇 |
2015年 | 43802篇 |
2014年 | 61175篇 |
2013年 | 92660篇 |
2012年 | 124859篇 |
2011年 | 132584篇 |
2010年 | 79748篇 |
2009年 | 75846篇 |
2008年 | 124115篇 |
2007年 | 131947篇 |
2006年 | 133873篇 |
2005年 | 129192篇 |
2004年 | 124308篇 |
2003年 | 119814篇 |
2002年 | 115879篇 |
2001年 | 183119篇 |
2000年 | 187966篇 |
1999年 | 158924篇 |
1998年 | 47193篇 |
1997年 | 41476篇 |
1996年 | 41628篇 |
1995年 | 40013篇 |
1994年 | 36752篇 |
1993年 | 34577篇 |
1992年 | 124634篇 |
1991年 | 120815篇 |
1990年 | 117507篇 |
1989年 | 113897篇 |
1988年 | 104813篇 |
1987年 | 102723篇 |
1986年 | 96716篇 |
1985年 | 92692篇 |
1984年 | 69297篇 |
1983年 | 59000篇 |
1982年 | 35177篇 |
1981年 | 31678篇 |
1979年 | 62889篇 |
1978年 | 44720篇 |
1977年 | 37761篇 |
1976年 | 35545篇 |
1975年 | 37965篇 |
1974年 | 45283篇 |
1973年 | 43145篇 |
1972年 | 40606篇 |
1971年 | 38140篇 |
1970年 | 35117篇 |
1969年 | 33798篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
In the 6th Basic Plan for Long-Term Electricity Supply and Demand (6th BPE) for Korea, for the first time, the environmental costs of air pollution caused by oxides of sulfur (SOx), oxides of nitrogen (NOx), and particulate matters (PM) from power plants were estimated and included. However, several deficiencies in evaluating the environmental costs were found. In this study, (1) the validity of the environmental costs used in the 6th BPE was assessed, (2) a systematic approach was suggested and used to improve the environmental costs estimation, and (3) the sensitivity of the cost of generating electricity to the environmental costs by fuel type with the proposed approach was discussed. We found that the applied environmental costs used in the 6th BPE did not fully include the demographic characteristics of Korea. By applying more realistic parameter values, it was found that the newly estimated environmental cost was about 23 times higher than the cost estimated in the original 6th BPE for coal-fired power plants and about 1.5 times higher for liquefied natural gas (LNG)-fired power plants, suggesting that LNG-fired power plants are more economical if using more realistic environmental costs. Thus, it is critical to check the validity of parameter values when calculating environmental costs. 相似文献
102.
103.
Evaluation of Adult versus Pediatric Transesophageal Echocardiography Probe Efficiency for Guiding Septal Puncture during Atrial Fibrillation Ablation 下载免费PDF全文
104.
Dynamic LVOT Obstruction and Aortic Stenosis in the Same Patient: A Case of Challenging Doppler Hemodynamics 下载免费PDF全文
Matthew W. Parker M.D. Francis J. Kiernan M.D. 《Echocardiography (Mount Kisco, N.Y.)》2015,32(6):1030-1032
We present a patient with both dynamic left ventricular outflow tract obstruction and valvular aortic stenosis. The aortic valve was calcified, and velocities and gradients measured by continuous‐wave Doppler met standard criteria for severe aortic stenosis. The increased subvalvular velocities invalidated assumptions of the simplified Bernoulli equation; correction using the longer form of the Bernoulli equation suggested a lower but still significant gradient. The complex shape of the subvalvular spectral Doppler envelope indicated supranormal systolic function and dynamic left ventricular outflow obstruction. Left heart catheterization with an end‐hole catheter was required to determine the subvalvular and valvular components of the obstruction. 相似文献
105.
106.
107.
108.
Jamaal L. Benjamin MD PhD Rebecca Dennis DO Stacy White Jr MD David Munson MD Sudha A. Anupindi MD Maciej Piskunowicz MD Kassa Darge MD PhD Ami Gokli MD Misun Hwang MD 《Journal of ultrasound in medicine》2020,39(5):1031-1036
Bowel diseases of prematurity, including necrotizing enterocolitis, are dreaded ailments of neonates. Early diagnosis is difficult, with clinical and radiographic findings often inconclusive. We present a novel use of contrast-enhanced ultrasound in detection of pediatric bowel disease. Early identification of compromised blood flow or an at-risk bowel can be quantitatively detected and monitored. This ability has implications for guidance of emerging therapies, allowing targeting of inflammation. These findings represent an advancement in detection of bowel disease in neonates. 相似文献
109.
Provocation of Atrial Fibrillation Triggers During Ablation: Does the Use of General Anesthesia Affect Inducibility? 下载免费PDF全文
110.