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   435篇
  免费   19篇
  国内免费   25篇
儿科学   21篇
妇产科学   8篇
基础医学   51篇
口腔科学   6篇
临床医学   47篇
内科学   104篇
皮肤病学   4篇
神经病学   13篇
特种医学   58篇
外科学   62篇
综合类   7篇
预防医学   17篇
眼科学   2篇
药学   52篇
肿瘤学   27篇
  2022年   3篇
  2021年   5篇
  2020年   2篇
  2019年   4篇
  2018年   7篇
  2017年   7篇
  2016年   16篇
  2015年   12篇
  2014年   7篇
  2013年   15篇
  2012年   23篇
  2011年   15篇
  2010年   14篇
  2009年   16篇
  2008年   13篇
  2007年   28篇
  2006年   17篇
  2005年   26篇
  2004年   13篇
  2003年   6篇
  2002年   11篇
  2001年   11篇
  2000年   6篇
  1999年   11篇
  1998年   18篇
  1997年   14篇
  1996年   18篇
  1995年   18篇
  1994年   16篇
  1993年   22篇
  1992年   7篇
  1991年   9篇
  1990年   11篇
  1989年   12篇
  1988年   8篇
  1987年   3篇
  1986年   3篇
  1985年   7篇
  1984年   4篇
  1983年   3篇
  1982年   4篇
  1981年   4篇
  1980年   2篇
  1979年   3篇
  1978年   2篇
  1976年   2篇
  1975年   1篇
排序方式: 共有479条查询结果,搜索用时 15 毫秒
151.
INTRODUCTION: A split liver for two adults is a good theoretical option but the number of cases is low. We have tried to assess the feasibility of this technique. MATERIALS AND METHODS: From April 2002 to April 2004, we evaluated 81 donors of which only 59 (72.8%) were used for transplantation of which 10 were grafted in other centers (pediatric or emergency code). Among the 49 donors the criteria for splitting were: ages >14 and <50 years, weight >70 and <100 kg, less than 3 days in the intensive care unit (ICU), hemodynamic stability, Na(+) < 160 mg/L, liver enzymes elevated no more than twofold, no macroscopic steatosis, and procurement in our hospital. RESULTS: The mean donor age was 50.7 years (range: 16 to 77) of whom 25 were men (51%). The mean weight was 65.7 kg (range: 50 to 100) and days of ICU stay, 3 (range: 1 to 23). Six grafts (12%) were split. The reasons for not splitting were: age (n = 26 [53%]), weight (n = 17 [34.7%]), UCI >3 days (n = 9 [18.3%]), Na(+) > 160 (n = 1 [2%]), blood liver test elevated (n = 5 [10.2%]), steatosis (n = 6 [12.2%]), and procurement outside our center (n = 20 [40.8%]). The donors not suitable for splitting had: only one criteria (n = 12 [24.4%]; 2 (n = 23 [46.9%], 3 (n = 6 [12.2%]) or 4 (n = 2 [4.1%]). If we had had two suitable recipients, we could performed six more liver transplantations (12.2% increase). CONCLUSIONS: The theoretical feasibility of a split liver for two adults is 12.2%, but the actual probability is lower because of lack of two adequate candidates.  相似文献   
152.
Reactive oxygen species (ROS) play a central role in ischemia-reperfusion injury after organ transplantation. They are degraded by endogenous radical scavengers such as antioxidant enzymes. The purpose of this study was to evaluate the temporal variations of antioxidant enzyme activities in liver transplant recipients. The study was performed in 13 liver transplant patients (11 men and 2 women). Blood samples were obtained pre- and postsurgical intervention: before transplant (T(0)), and 1, 6, 12, 24, 48, and 72 hours, as well as 5 and 7 days thereafter. We determined total and specific superoxide dismutase (SOD) activity, catalase (CAT), glutathione peroxidase (GPX), and glutathione reductase (GR) activities as well as malondialdehyde (MDA) and low-density lipoproteins (LDL). The results showed increased SOD and mainly GPX activities after liver transplantation, which correlated with MDA levels. Total SOD activity was mainly represented by Mn-SOD (75%) and Cu,Zn-SOD (25%), whereas Fe-SOD was not detected. In conclusion, the enhanced antioxidant enzyme activities reported in this study indicated a control of oxidative stress generated in liver transplantation. In this sense, although MDA levels showed an enormeous increase at 1 hour after transplantation, the lipid peroxidation was compensated for by GPX activity.  相似文献   
153.
154.

Background  

Surveillance of Over-the-Counter pharmaceutical (OTC) sales as a potential early indicator of developing public health conditions, in particular in cases of interest to Bioterrorism, has been suggested in the literature. The data streams of interest are quite non-stationary and we address this problem from the viewpoint of linear adaptive filter theory: the clinical data is the primary channel which is to be estimated from the OTC data that form the reference channels.  相似文献   
155.
156.
157.
The life expectancy of the current Spanish population is 78 years, with some 20% of the population aged over 65 years. The continuing increase in the demand for transplants has led to widening of the criteria for acceptance of donors without worsening the results, but without reducing transplant waiting lists or mortality. This has resulted in the need to include the concept of the expanded criteria donor (ECD). We undertook a retrospective study of 77 donors from a hospital with no neurosurgery service from January 2000 to December 2005. Four of the donors younger than 60 years of age (n = 38) were not appropriate (10.5%), whereas five of the donors older than 60 years of age (n = 39) were not appropriate (12.8%; P = NS). The older donors provided 47 used kidneys (60.2%) and 22 livers (56.4%), slightly fewer than those obtained from the younger donors, though the difference was not significant. Thus, ECDs, those older than 60 years of age, did not result in a significant loss of kidneys or livers available for transplantation. Other factors associated with systemic vascular disease and accompanying disorders could be determinant when predicting the usefulness of organs for transplantation.  相似文献   
158.
159.
160.
INTRODUCTIONIntussusception in adults accounts for less than 5% of all intussusceptions. It occurs when a segment of intestine invaginates into itself.PRESENTATION OF A CASEWe report a case of ileocolic intussusception in an adult caused by a giant ileal lipoma.DISCUSSIONIntussusceptions can be classified as ileocolic, ileocecal, colo-colic and ileo-ileal. Most are due to neoplasms (60% malign and 24–40% benign). In the colon, the possibility of malignancy is higher than in small intestine.Lipomas are the most common benign mesenchymal intestinal tumors, accounting for less than 5% of all gastrointestinal tumors. They are more frequent in colon than small intestine. Small lipomas (less than 2 cm) are usually asymptomatic. Larger lesions may produce symptoms such as abdominal pain, obstruction or intussusception. Lipomas can be diagnosed with endoscopy, capsule endoscopy, barium enemas, CT and US.CONCLUSIONIntussusceptions in adults is a rare condition, most of them are caused by a malign neoplasms followed by benign neoplasms. US and CT are useful for diagnosis. Surgery is mandatory.  相似文献   
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