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   3455篇
  免费   141篇
  国内免费   18篇
耳鼻咽喉   23篇
儿科学   61篇
妇产科学   41篇
基础医学   545篇
口腔科学   61篇
临床医学   195篇
内科学   883篇
皮肤病学   52篇
神经病学   211篇
特种医学   63篇
外科学   692篇
综合类   7篇
预防医学   96篇
眼科学   37篇
药学   199篇
中国医学   17篇
肿瘤学   431篇
  2023年   12篇
  2022年   25篇
  2021年   61篇
  2020年   34篇
  2019年   57篇
  2018年   86篇
  2017年   51篇
  2016年   51篇
  2015年   63篇
  2014年   98篇
  2013年   98篇
  2012年   182篇
  2011年   186篇
  2010年   120篇
  2009年   110篇
  2008年   171篇
  2007年   182篇
  2006年   223篇
  2005年   218篇
  2004年   206篇
  2003年   217篇
  2002年   205篇
  2001年   115篇
  2000年   99篇
  1999年   105篇
  1998年   67篇
  1997年   27篇
  1996年   31篇
  1995年   29篇
  1994年   22篇
  1993年   27篇
  1992年   51篇
  1991年   52篇
  1990年   44篇
  1989年   50篇
  1988年   32篇
  1987年   41篇
  1986年   28篇
  1985年   20篇
  1984年   14篇
  1983年   16篇
  1982年   9篇
  1980年   8篇
  1979年   9篇
  1978年   9篇
  1977年   6篇
  1974年   7篇
  1970年   5篇
  1969年   8篇
  1966年   4篇
排序方式: 共有3614条查询结果,搜索用时 250 毫秒
1.
2.
3.
The effect of the hepatic energy status on the development of posttraumatic jaundice (PTJ) was studied to clarify the mechanism of PTJ. Fifty-four patients with severe torso injury who were expected to develop PTJ on admission with an average Injury Severity Score of 27 were selected for this study. They were retrospectively divided into three groups according to their maximum bilirubin concentration by day 10: group H, 12 patients with marked elevation of serum bilirubin (>8 g/dl); group L, 23 with mild bilirubinemia (2–8 g/dl); and group N, 19 with no bilirubinemia (<2 g/dl). Group H patients, in whom trauma-related shock was severe and prolonged, developed severe hyperbilirubinemia, and their arterial ketone body ratio (AKBR), which reflects the hepatic mitochondrial redox state and is closely correlated to its energy production, was significantly lower throughout the first week. In contrast, the AKBR increased to an above normal level, indicating enhanced energy production in groups N and L. The serum direct/total bilirubin was also higher in group H. The abnormal hepatic energy metabolism is considered to have reduced the excretion of conjugated bilirubin from the hepatocytes into the bile canaliculi, which is a process that has to proceed against the bilirubin concentration gradient. The subsequent diffusion of the accumulated water-soluble conjugated bilirubin in hepatocytes into the blood is thus considered to be one of the causes of PTJ.  相似文献   
4.
Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) were measured in a mild case of dyssegmental dysplasia. X-ray pictures of a female baby born vaginally at 39 weeks of gestation showed short, bent, dumbbell-shaped long bones of the limbs and profound dyssegmental ossification in the spine, findings characteristic of dyssegmental dysplasia. When the levels of MMP-1, MMP-2, MMP-9, TIMP-1, and TIMP-2 were measured, the levels of MMP-2 and TIMP-1 were significantly reduced. This case might provide a clue to disclose the etiology of dyssegmental dysplasia.  相似文献   
5.
6.
Ultrasonography was performed in 45 cases of gastric cancer. Specimens from all 45 cases of gastric cancer were subjects to ultrasonographic study by the water immersion method for comparison with histology. In 32 of these 45 cases in vivo ultrasonographic evaluation was performed prospectively. The overall accuracy rates for the diagnosis of the depth of cancerous invasion were almost 80% in both in vitro and in vivo studies. In vivo ultrasonographic findings agreed well with those from the specimen studies. Ultrasonography was considered to be useful in the diagnosis of gastric malignancies.  相似文献   
7.
8.
Summary Haemorrhage in regions remote from the site of following intracranial operations is rare, but they do occur. We performed supratentorial craniotomy on 639 patients between the time of introduction of computed tomography (CT) for clinical use in 1983 and June 1992; subarachnoid haemorrhage (SAH) in the posterior fossa occurred postoperatively in six of these cases. These included four patients with tumours in the sellar region, one with an arteriovenous malformation (AVM) and one who underwent superficial temporal artery (STA)-middle cerebral artery (MCA) anastomosis. The ages of the six patients ranged from 17–72 years.Haemorrhage occurred on the day of operation in one case and was detected on CT examination on the day following surgery in the remaining five cases. Of three patients with disturbance of consciousness, two underwent suboccipital craniectomy for reduction of intracranial pressure, while one received barbiturate therapy and later underwent cerebrospinal fluid (CSF) shunt surgery. No special treatment was necessary for the remaining three patients with less serious lesions. Five of the six patients ultimately recovered their pre-operative neurological status apart from the primary diseases.Factors inducing such haemorrhages seem likely to include displacement of the cerebellum by reduced CSF pressure during and after operations, and stretching and tearing of the veins and venules in the sulci of the tentorial surface of the cerebellum. Consideration should therefore be given to the maintenance of an appropriate CSF pressure during operation; this is particularly important in elderly patients and those with an atrophied cerebral cortex.  相似文献   
9.
10.
A 23-year-old woman had lower abdominal pain, diarrhea and bloody stool was admitted and given a diagnosis of influenza B. Her home doctor had started treatment by neuraminidase inhibitor (oseltamivir) the previous day. Colonoscopic examination revealed an area of hemorrhage and erosion in the left transverse colon. After halting oseltamivir treatment these symptoms disappeared and her colonoscopic findings improved. A drug-induced lymphocyte stimulation test was positive for oseltamivir. This case is the first reported case of acute hemorrhagic colitis induced by oseltamivir.  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