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   134658篇
  免费   5802篇
  国内免费   324篇
耳鼻咽喉   2048篇
儿科学   4287篇
妇产科学   2906篇
基础医学   18018篇
口腔科学   4511篇
临床医学   8314篇
内科学   33561篇
皮肤病学   4400篇
神经病学   10538篇
特种医学   3377篇
外国民族医学   1篇
外科学   16591篇
综合类   724篇
一般理论   36篇
预防医学   13008篇
眼科学   2949篇
药学   9111篇
  1篇
中国医学   678篇
肿瘤学   5725篇
  2023年   842篇
  2022年   743篇
  2021年   2908篇
  2020年   1452篇
  2019年   3177篇
  2018年   5110篇
  2017年   2981篇
  2016年   2774篇
  2015年   3097篇
  2014年   3701篇
  2013年   5513篇
  2012年   9417篇
  2011年   10105篇
  2010年   5143篇
  2009年   3791篇
  2008年   8095篇
  2007年   8617篇
  2006年   8015篇
  2005年   7934篇
  2004年   7039篇
  2003年   6625篇
  2002年   6208篇
  2001年   4040篇
  2000年   4726篇
  1999年   3505篇
  1998年   691篇
  1997年   530篇
  1996年   490篇
  1995年   395篇
  1994年   317篇
  1993年   297篇
  1992年   1352篇
  1991年   1125篇
  1990年   1006篇
  1989年   842篇
  1988年   711篇
  1987年   682篇
  1986年   682篇
  1985年   573篇
  1984年   419篇
  1983年   320篇
  1979年   355篇
  1975年   285篇
  1974年   324篇
  1973年   359篇
  1972年   302篇
  1971年   317篇
  1970年   297篇
  1969年   302篇
  1968年   272篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
Hypoxia is related to poor prognosis because it is associated to chemo-and radioresistance. During recent years the evolution of imaging methods like PET/CT and MRI has meant the appearance of new perspectives with direct implications in radiation therapy. We discuss previous experiences in staging, planning and in the follow-up process with these techniques for measuring tumour hypoxia.  相似文献   
52.
53.
54.
55.
IntroductionTo analyse the effectiveness and safety of the indwelling pleural catheter in the management of recurrent malignant pleural effusion.Patients and methodsA prospective multicentre study was performed in 63 consecutive outpatients from four Spanish hospitals. A total of 43 men and 20 women were included, with a median age of 67 years. In seven of the cases treatment with pleurodesis had failed; in five other cases their lung was trapped; in another five cases after repeat therapeutic thoracocentesis, and the rest of them as a preference choice to pleurodesis. All patients had an indwelling pleural catheter inserted (PleurX®, Denver Biomedical).ResultsMost of patients (94.5%) reported an improvement in their respiratory symptoms (cough and dyspnoea) and their ability to function independently. Average length of the catheterisation was 45 days (6-222). Average amount of drained pleural effusion was 75 ml, with a frequency of drainage of between 3 and 4 times per week and once fortnightly. Spontaneous pleurodesis was achieved following 34.9% of procedures. No complications occurred during the insertion of the catheter. The post-catheterisation complications were empyema (3 cases), chest pain (2 cases), and tumour metastasis (3 cases).ConclusionsThe use of an indwelling pleural catheter is an effective palliative treatment in the outpatient management for patients suffering malignant pleural effusion. It is also a simple treatment that can be easily applied, does not require hospitalisation and can be easily managed by the patient at home, with a low rate of complications.  相似文献   
56.
AIMS: The aims of our study were to determine if insulin resistance is associated with increased plasma levels of non-esterified fatty acids (NEFA), glycerol, 3-hydroxybutyrate and triglycerides in obese children. We also studied whether the presence of acanthosis nigricans (AN) led to further alterations in the above parameters. METHODS: A total of 101 children were studied on their first visit to the paediatric endocrine clinic. Seventy-four were obese, 30 of them with AN. The remaining 27 were non-obese healthy children (control group). NEFAs, glycerol, triglycerides, 3-hydroxybutyrate, insulin, leptin, adiponectin and glucose were determined in blood samples obtained after overnight fasting. The insulin resistance index (IRI) was calculated following the homeostasis model assessment (HOMA). Data from the three groups were compared using appropriate statistical tests. RESULTS: No differences in age, sex ratio and pubertal stage were observed among the three groups. The group of children with the highest body mass index (BMI) showed higher plasma levels of insulin and leptin, higher IRI and lower plasma levels of adiponectin. As insulin and IRI increased, NEFA and 3-hydroxybutyrate decreased and triglycerides increased. When obese children were categorized by BMI, the presence of AN further exacerbated these differences. CONCLUSIONS: In obese children, insulin resistance is associated with plasma lipid alterations suggestive of both decreased adipose tissue lipolysis and hepatic beta-oxidation and increased hepatic synthesis of triglycerides. Such a metabolic condition may facilitate fat storage and hinder weight loss.  相似文献   
57.
58.
59.
Hepatic encephalopathy is a reversible state of altered cognition that may occur in patients with acute or chronic liver disease or porto-systemic shunt, and in which known neurological or psychiatric signs may develop. Nitrogenated substances from intestinal digestion reach the brain without being cleared by their passage through the liver due to the presence of porto-systemic shunt. We report two cases of patients with porto-systemic shunt diagnosed with recurrent chronic hepatic encephalopathy refractory to conventional medical treatment. They were satisfactorily treated with shunt embolization using interventionist radiology techniques.  相似文献   
60.
Five patients with idiopathic transient osteoporosis were examined. Bone scanning and MRI was helpful in the diagnosis to differentiate of necrosis and all patients recovered completely with conservative and symptomatic treatment. There was no history of trauma in all patients. MRI was realized previously in all cases to confirm the diagnosis and after the resolution of symptomathology.  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