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   2500810篇
  免费   203006篇
  国内免费   4769篇
耳鼻咽喉   36046篇
儿科学   76312篇
妇产科学   65568篇
基础医学   351354篇
口腔科学   70235篇
临床医学   228259篇
内科学   494465篇
皮肤病学   50246篇
神经病学   213807篇
特种医学   100183篇
外国民族医学   895篇
外科学   378173篇
综合类   58009篇
现状与发展   4篇
一般理论   1157篇
预防医学   200552篇
眼科学   59112篇
药学   185589篇
  4篇
中国医学   4507篇
肿瘤学   134108篇
  2018年   26461篇
  2017年   20390篇
  2016年   22516篇
  2015年   25653篇
  2014年   36968篇
  2013年   56467篇
  2012年   76533篇
  2011年   80765篇
  2010年   47175篇
  2009年   45305篇
  2008年   76749篇
  2007年   81700篇
  2006年   82195篇
  2005年   80518篇
  2004年   77608篇
  2003年   74850篇
  2002年   73813篇
  2001年   113492篇
  2000年   117328篇
  1999年   99460篇
  1998年   29562篇
  1997年   26944篇
  1996年   26680篇
  1995年   25741篇
  1994年   24163篇
  1993年   22533篇
  1992年   80108篇
  1991年   77077篇
  1990年   74167篇
  1989年   71423篇
  1988年   66435篇
  1987年   65315篇
  1986年   61932篇
  1985年   59068篇
  1984年   45114篇
  1983年   38506篇
  1982年   24097篇
  1981年   21473篇
  1980年   20109篇
  1979年   41885篇
  1978年   29681篇
  1977年   24973篇
  1976年   23379篇
  1975年   24383篇
  1974年   30111篇
  1973年   28396篇
  1972年   26525篇
  1971年   24365篇
  1970年   22940篇
  1969年   21251篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
91.
92.
93.
Pancreatic panniculitis is an uncommon condition that can occur in association with pancreatic disease. We present a case of pancreatic panniculitis in a female pancreas-kidney transplant recipient 5 months post-transplant. The patient was on standard immunosuppressive medications and had acute rejection of her renal allograft. The diagnosis of allograft pancreatitis and rejection presenting with pancreatic panniculitis was supported clinically, histopathologically and by laboratory and imaging data. This is the fourth case of pancreatic panniculitis occurring in a transplant recipient and the first in a simultaneous pancreas-kidney transplant recipient. It is also the first case associated with allograft rejection. Clinicians should be aware that pancreatic panniculitis may be a manifestation of underlying allograft pancreatic disease.  相似文献   
94.
The purpose of this study is to determine the role of liver biopsy and outcome of patients undergoing donor evaluation for adult-to-adult right hepatic lobe living donor liver transplantation (LDLT). Records of patients presenting for a comprehensive donor evaluation between 1997 and February 2005 were reviewed. Liver biopsy was performed only in patients with risk factors for abnormal histology. Two hundred and sixty patients underwent a comprehensive donor evaluation and 116 of 260 (45%) were suitable for donation, 14 of 260 (5.4%) did not complete evaluation and 130 of 260 (50%) were rejected. Four patients underwent unsuccessful hepatectomy surgery due to discovery of intraoperative abnormalities. Between 1997 and 2001, the acceptance rate of donor candidates (63%) was higher than 2002-2005 (36%), p < 0.0001. Sixty-six of the 150 eligible patients (44%) fulfilled criteria for liver biopsy and 28 of 66 (42%) had an abnormal finding. Less than half of the patients undergoing donor evaluation were suitable donors and the donor acceptance rate has declined over time. A large proportion of the patients undergoing liver biopsy have abnormal findings. Our evaluation process failed to identify 4 of 103 who had aborted donor surgeries.  相似文献   
95.
We previously reported poorer survival among non-Hispanic blacks and Hispanics with idiopathic pulmonary fibrosis (IPF) compared to non-Hispanic whites at our center. In the current study, we hypothesized that these disparities would exist in a nationwide cohort of wait-listed patients with IPF. We performed a retrospective cohort study of 2635 patients with IPF listed for lung transplantation between 1995 and 2003 at 94 transplant centers in the United States. The age-adjusted mortality rate was higher among non-Hispanic blacks [hazard ratio (HR) = 1.24, 95% confidence interval (CI) 1.06-1.45, p = 0.009] and Hispanics (HR = 1.29, 95% CI 1.06-1.56, p = 0.01) compared to non-Hispanic whites. These findings persisted after adjustment for transplantation, medical comorbidities and socioeconomic status. Worse lung function at the time of listing appeared to explain some of these differences (HR for non-Hispanic blacks after adjustment for forced vital capacity percent predicted = 1.16, 95% CI 0.98-1.36, p = 0.09; HR for Hispanics = 1.21, 95% CI 0.99-1.48, p = 0.056). In summary, black and Hispanic patients with IPF have worse survival than whites after listing for lung transplant.  相似文献   
96.
97.
We assessed midsagittal corpus callosum size in sickle cell disease (SCD) and its relationship to lesion volume, lesion location, and cognitive functioning. Twenty-eight children with SCD and 16 demographic controls completed magnetic resonance imaging (MRI) and neuropsychological testing. Corpus callosum (CC) size was smaller for children with silent infarcts (n = 8) or overt stroke (n = 8) than for those without visible infarcts (n = 12) or control participants. Lesion volume was a robust predictor of IQ and other cognitive scores; total CC size did not typically add explanatory power for these measures. The size of the rostral body of the CC, however, independently predicted measures of distractibility, speeded production, and working memory. Posterior CC size was also decreased among many of the children with SCD, even in the absence of visible infarcts in this region. Brain morphology appears to provide additional information about SCD-related effects on the brain above and beyond visible infarcts.  相似文献   
98.
OBJECTIVE: Gelastic seizures are a frequent and well established manifestation of the epilepsy associated with hypothalamic hamartomas. The scalp EEG recordings very seldom demonstrate clear spike activity and the information about the ictal epilepsy dynamics is limited. In this work, we try to isolate epileptic rhythms in gelastic seizures and study their generators. METHODS: We extracted rhythmic activity from EEG scalp recordings of gelastic seizures using decomposition in independent components (ICA) in three patients, two with hypothalamic hamartomas and one with no hypothalamic lesion. Time analysis of these rhythms and inverse source analysis was done to recover their foci of origin and temporal dynamics. RESULTS: In the two patients with hypothalamic hamartomas consistent ictal delta (2-3 Hz) rhythms were present, with subcortical generators in both and a superficial one in a single patient. The latter pattern was observed in the patient with no hypothalamic hamartoma visible in MRI. The deep generators activated earlier than the superficial ones, suggesting a consistent sub-cortical origin of the rhythmical activity. CONCLUSIONS: Our data is compatible with early and brief epileptic generators in deep sub-cortical regions and more superficial ones activating later. SIGNIFICANCE: Gelastic seizures express rhythms on scalp EEG compatible with epileptic activity originating in sub-cortical generators and secondarily involving cortical ones.  相似文献   
99.
Endoscopic clips have been used mainly for control of gastrointestinal (GI) bleeding and occasionally for closure of GI perforations. However, closure of spontaneous esophageal perforation (Boerhaave's syndrome) by clipping has not been reported. We described successful non-surgical closure of spontaneous esophageal perforation by endoscopic clipping in a patient with bilateral pyopneumothorax and septicemia.  相似文献   
100.
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