首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1385940篇
  免费   99543篇
  国内免费   2463篇
耳鼻咽喉   19397篇
儿科学   45556篇
妇产科学   39614篇
基础医学   201542篇
口腔科学   37465篇
临床医学   118975篇
内科学   274013篇
皮肤病学   27785篇
神经病学   109733篇
特种医学   53329篇
外国民族医学   367篇
外科学   213172篇
综合类   28004篇
现状与发展   2篇
一般理论   450篇
预防医学   102483篇
眼科学   31967篇
药学   105605篇
  2篇
中国医学   2722篇
肿瘤学   75763篇
  2018年   14297篇
  2017年   10752篇
  2016年   12156篇
  2015年   14015篇
  2014年   19441篇
  2013年   29330篇
  2012年   41033篇
  2011年   43915篇
  2010年   25658篇
  2009年   24118篇
  2008年   42080篇
  2007年   45460篇
  2006年   45590篇
  2005年   44897篇
  2004年   43176篇
  2003年   41590篇
  2002年   40912篇
  2001年   59141篇
  2000年   60342篇
  1999年   51741篇
  1998年   15533篇
  1997年   13872篇
  1996年   13912篇
  1995年   13194篇
  1994年   12481篇
  1993年   11551篇
  1992年   41571篇
  1991年   40888篇
  1990年   40338篇
  1989年   39131篇
  1988年   36547篇
  1987年   35768篇
  1986年   34087篇
  1985年   32574篇
  1984年   24424篇
  1983年   21283篇
  1982年   13022篇
  1981年   11492篇
  1979年   22957篇
  1978年   16191篇
  1977年   14051篇
  1976年   13238篇
  1975年   14447篇
  1974年   16934篇
  1973年   16311篇
  1972年   15503篇
  1971年   14373篇
  1970年   13332篇
  1969年   12855篇
  1968年   12092篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
81.
82.

Aims

Variations of the anatomy of donor hepatic arteries increase the number of arterial anastomoses during liver transplantation and, possibly, the incidence of hepatic artery thrombosis (HAT). In this study, we describe the arterial anatomic variations in liver grafts procured and transplanted by a single center in Greece, the techniques of arterial anastomosis, and their effect on the incidence of early HAT.

Materials and Methods

From January 2013 to December 2017, the arterial anatomy of 116 grafts procured for liver transplantation were recorded, as well as the technique of arterial anastomosis and the incidence of early hepatic artery thrombosis (HAT <30 days).

Results

A single hepatic artery was recorded in 72.41% of the procured grafts, an aberrant left hepatic artery (accessory or replaced) in 18 grafts (15.52%), and an aberrant right hepatic artery (accessory or replaced) in 17 grafts (14.66%), while other variations were observed in less than 1% of the procured livers. Of the 116 primary liver transplantations, 6 patients (5.17%) developed early HAT <30 days. Two of these patients (1.72%) had 1 anastomosis of the hepatic artery and 4 (3.45%) had 2 anastomoses due to anatomic variations.

Conclusions

Anatomic variations of the hepatic artery in liver grafts is a common finding and increase the incidence of early HAT but not to a degree to make these grafts unusable.  相似文献   
83.

Introduction

The fast track / ultra-fast-track protocols are techniques used to optimise the patient care process and a quick recovery after cardiac surgery. They are one of the mainstays of efficient practice. With their use, the length of hospital and intensive care unit (ICU) stays are reduced, with a direct impact on costs and the quality of the health service.

Objective

To compare the length of stay in the ICU, length of hospital stay, and post-operative mortality in ultra-fast-track extubated (uFTE) patients and those with conventional extubation (CE) after cardiac surgery.

Methods

Longitudinal, analytical, retrospective study was conducted, with the period between the time of surgery and discharge being included as the study period.

Results

A total of 396 patients older than 18 years who required cardiac surgery were included, of whom 207 patients had (uFTE) and 189 had CE. Although the groups were not comparable due to the statistical differences found, when performing the multivariate adjustment, uFTE maintained its statistical independence and was associated with lower cardiovascular morbidity, such as myocardial ischaemia (95% CI: 0.37-0.86; P = .01) and lower post-surgical vasopressor requirement (95% CI: 0.18-0.49; P < .01). No significant differences were found in the length of hospital stay, ICU stay, or post-operative mortality in the ICU.

Conclusion

Implementing the uFTE strategy, decreases cardiovascular morbidity and vasopressor requirement. The change to uFTE should be accompanied by changes in models and practices in patient recovery to standardised protocols. This study shows that uFTE did not reduce the length of ICU stay, hospital stay, or mortality.  相似文献   
84.
85.
86.
Background and Aims: Gastric antral vascular ectasia (GAVE) is commonly found in patients with cirrhosis, but it is also associated with other diseases in the absence of cirrhosis. Whether GAVE confers a different severity of gastrointestinal (GI) bleeding between patients with and without cirrhosis remains unknown. We aim to examine whether there is a difference in clinically significant GI bleeding due to GAVE in patients with or without cirrhosis. Methods: This is a retrospective case-control study of patients who were diagnosed with GAVE between January 2000 and June 2014. Patients were categorized into cirrhosis and noncirrhosis groups, and those with an additional GI bleeding source were excluded. Univariate comparisons and multivariable models were constructed using logistic regression. Results: In total, 110 patients diagnosed with GAVE on esophagogastroduodenoscopy (EGD) were included in our analysis; 84 patients had cirrhosis (76.4%) and 26 (23.6%) did not. Active GI bleeding was more prevalent in patients without cirrhosis (63.4% vs. 32.1%, p=0.003) despite similar indications for EGD, and endoscopic treatment with argon plasma coagulation (APC) was required more often in this group, approaching statistical significance (27% vs. 10.7%, p=0.056). There was no difference in bleeding severity, as evidenced by similar re-bleeding rates, surgery, or death attributed to uncontrolled bleeding. The strongest independent risk factor for GI bleeding was the absence of cirrhosis (odds ratio (OR): 5.151 (95% confidence interval (CI): 1.08-24.48, p=0.039). Conclusions: Patients with GAVE in the absence of cirrhosis are at higher risk for active GI bleeding and require more frequent endoscopic treatment than similar patients with cirrhosis. It may be worthwhile to treat GAVE in this population even in the absence of active bleeding.  相似文献   
87.
Health care expenditure in Germany shows clear regional differences. Such geographic variations are often seen as an indicator for inefficiency. With its homogeneous health care system, low co‐payments and uniform prices, Germany is a particularly suited example to analyse regional variations. We use data for the year 2011 on expenditure, utilization of health services and state of health in Germany's statutory health insurance system. This data, which originate from a variety of administrative sources and cover about 90% of the population, are enriched with a wealth of socio‐economic variables, data on pollutants, prices and individual preferences. State of health and demography explains 55% of the differences as measured by the standard deviation while all control variables account for a total of 72% of the differences at county level. With other measures of variation, we can account for an even greater proportion. A higher proportion of variation than usually supposed can thus be explained. Whilst this study cannot quantify inefficiencies, our results contradict the thesis that regional variations reflect inefficiency. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
88.
89.
90.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号