全文获取类型
收费全文 | 6664篇 |
免费 | 678篇 |
国内免费 | 48篇 |
专业分类
耳鼻咽喉 | 53篇 |
儿科学 | 201篇 |
妇产科学 | 169篇 |
基础医学 | 846篇 |
口腔科学 | 58篇 |
临床医学 | 753篇 |
内科学 | 1379篇 |
皮肤病学 | 200篇 |
神经病学 | 464篇 |
特种医学 | 510篇 |
外科学 | 896篇 |
综合类 | 235篇 |
一般理论 | 2篇 |
预防医学 | 508篇 |
眼科学 | 74篇 |
药学 | 274篇 |
2篇 | |
中国医学 | 32篇 |
肿瘤学 | 734篇 |
出版年
2022年 | 46篇 |
2021年 | 118篇 |
2020年 | 76篇 |
2019年 | 94篇 |
2018年 | 78篇 |
2017年 | 103篇 |
2016年 | 88篇 |
2015年 | 125篇 |
2014年 | 178篇 |
2013年 | 215篇 |
2012年 | 303篇 |
2011年 | 316篇 |
2010年 | 231篇 |
2009年 | 235篇 |
2008年 | 248篇 |
2007年 | 286篇 |
2006年 | 298篇 |
2005年 | 261篇 |
2004年 | 279篇 |
2003年 | 265篇 |
2002年 | 239篇 |
2001年 | 231篇 |
2000年 | 228篇 |
1999年 | 179篇 |
1998年 | 154篇 |
1997年 | 121篇 |
1996年 | 110篇 |
1995年 | 96篇 |
1994年 | 72篇 |
1993年 | 91篇 |
1992年 | 127篇 |
1991年 | 129篇 |
1990年 | 106篇 |
1989年 | 132篇 |
1988年 | 139篇 |
1987年 | 126篇 |
1986年 | 129篇 |
1985年 | 104篇 |
1984年 | 77篇 |
1983年 | 80篇 |
1982年 | 65篇 |
1981年 | 35篇 |
1980年 | 43篇 |
1979年 | 50篇 |
1978年 | 52篇 |
1977年 | 34篇 |
1976年 | 41篇 |
1975年 | 38篇 |
1955年 | 43篇 |
1954年 | 38篇 |
排序方式: 共有7390条查询结果,搜索用时 214 毫秒
2.
3.
4.
Dr. Arni Raghavendrarao Raghuram M.Ch. Subbiah Kumar MD Kathamuthu Balamurugan DA Arulmurugan DA Ramiah Krishnan M.Ch. Perichiappan Sivakami BS Eluvathingal Varghese John M.Ch. 《Indian Journal of Thoracic and Cardiovascular Surgery》2006,22(3):178-181
Background Beating heart surgery has now become the commonest technique of doing Coronary Artery Bypass Graft Surgery (CABG) in our country.
It is being used even in such high risk situations like diffuse coronary disease and Critical Left Main stem Stenosis (LMCS)
with good results. The aim of this study is to retrospectively review our results in Off-Pump Coronary Artery Bypass Surgery
(OPCAB) in patients with critical left main stem stenosis.
Methods This study is a retrospective analysis of the data of patients who underwent primary coronary artery bypass surgery. During
the period from April 2003 to September 2005 a total of 64 patients underwent OPCAB procedure for critical LMCS. During the
same period 10 patients underwent CABG on Cardio Pulmonary Bypass (CPB). The age range was 36–77yrs. The sex distribution
was M: F 53∶10. Ten patients were done as emergency. 2 of them were on Intra Aortic Balloon Pump (IABP) support preoperatively.
10 patients were high risk with a Euro score of ≥5.
Results Left Internal Mammary Artery (LIMA) was used in 78% of cases. Average grafts per patient was 2.96. The median ventilation
time was 5.91 hrs. New IABP insertion in postoperative period was required in 1 patient. One patient was reexplored for bleeding.
There was one perioperative myocardial infarction. 57% of patients did not need any blood transfusion. There was no conversion
to CPB. There was no operative mortality. Inotropes were used in ten cases.
Conclusions OPCAB is a safe method of revascularization in patients with critical LMCS. Preoperative IABP is useful in patients with cardiogenic
shock. However, there is a place for CPB in patients needing additional procedures like Mitral Valve repair (MV repair) or
Dor's procedure or when the vessels are very diffusely diseased. Those patients who are unstable despite IABP support may
be managed by Beating heart On Pump (BHOP) technique. 相似文献
5.
6.
7.
8.
Sabrina Hundt Ulrike Haug Hermann Brenner 《Cancer epidemiology, biomarkers & prevention》2007,16(10):1935-1953
BACKGROUND: Despite different available methods for colorectal cancer (CRC) screening and their proven benefits, morbidity, and mortality of this malignancy are still high, partly due to low compliance with screening. Minimally invasive tests based on the analysis of blood specimens may overcome this problem. The purpose of this review was to give an overview of published studies on blood markers aimed at the early detection of CRC and to summarize their performance characteristics. METHOD: The PUBMED database was searched for relevant studies published until June 2006. Only studies with more than 20 cases and more than 20 controls were included. Information on the markers under study, on the underlying study populations, and on performance characteristics was extracted. Special attention was given to performance characteristics by tumor stage. RESULTS: Overall, 93 studies evaluating 70 different markers were included. Most studies were done on protein markers, but DNA markers and RNA markers were also investigated. Performance characteristics varied widely between different markers, but also between different studies using the same marker. Promising results were reported for some novel assays, e.g., assays based on SELDI-TOF MS or MALDI-TOF MS, for some proteins (e.g., soluble CD26 and bone sialoprotein) and also for some genetic assays (e.g., L6 mRNA), but evidence thus far is restricted to single studies with limited sample size and without further external validation. CONCLUSIONS: Larger prospective studies using study populations representing a screening population are needed to verify promising results. In addition, future studies should pay increased attention to the potential of detecting precursor lesions. 相似文献
9.
10.