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   2674篇
  免费   107篇
  国内免费   5篇
耳鼻咽喉   34篇
儿科学   135篇
妇产科学   52篇
基础医学   279篇
口腔科学   127篇
临床医学   207篇
内科学   535篇
皮肤病学   68篇
神经病学   186篇
特种医学   71篇
外科学   508篇
综合类   52篇
预防医学   102篇
眼科学   85篇
药学   234篇
中国医学   11篇
肿瘤学   100篇
  2023年   20篇
  2022年   37篇
  2021年   78篇
  2020年   50篇
  2019年   78篇
  2018年   78篇
  2017年   72篇
  2016年   68篇
  2015年   81篇
  2014年   103篇
  2013年   140篇
  2012年   203篇
  2011年   222篇
  2010年   128篇
  2009年   109篇
  2008年   150篇
  2007年   133篇
  2006年   138篇
  2005年   134篇
  2004年   104篇
  2003年   110篇
  2002年   109篇
  2001年   55篇
  2000年   40篇
  1999年   39篇
  1998年   23篇
  1997年   14篇
  1996年   17篇
  1995年   11篇
  1994年   6篇
  1993年   10篇
  1992年   16篇
  1991年   20篇
  1990年   19篇
  1989年   14篇
  1988年   29篇
  1987年   11篇
  1986年   15篇
  1985年   17篇
  1984年   9篇
  1983年   6篇
  1982年   6篇
  1981年   6篇
  1976年   3篇
  1975年   6篇
  1974年   12篇
  1973年   7篇
  1970年   5篇
  1969年   4篇
  1968年   4篇
排序方式: 共有2786条查询结果,搜索用时 0 毫秒
61.
62.
63.
Charcot Leyden crystals are colorless, hexagonal, bipyramidal crystals formed from aggregation of material from disintegrating eosinophils. Eosinophilic infiltrate along with the presence of Charcot Leyden crystals is an indirect evidence of parasitic infestation. Here, we report a case where fine‐needle aspiration cytology smears prepared from hepatic space occupying lesion showed numerous Charcot Leyden crystals along with eosinophilic infiltrate, indicating parasitic infection. Diagn. Cytopathol. 2015;43:392–394. © 2014 Wiley Periodicals, Inc.  相似文献   
64.
65.
Low-voltage electrochemical actuation of radical polymer gels has been demonstrated in an organic electrolyte. Polymer gels were prepared by post-modification of active-ester precursor gels with an amine-functionalised radical. A combination of few-layer graphene and multiwall carbon nanotubes gave high conductivity and improved actuation in the gels, with 32% linear actuation. The actuator system showed good stability over at least 10 cycles, showing its promise. The cycle time was several hours due to mass-transport limited transport of ions and solvent into the device.

Reversible actuation of a radical-gel over many cycles with large strain.  相似文献   
66.

Objective

To develop and validate INCLEN Diagnostic Tool for Autism Spectrum Disorder (INDT-ASD).

Design

Diagnostic test evaluation by cross sectional design

Setting

Four tertiary pediatric neurology centers in Delhi and Thiruvanthapuram, India.

Methods

Children aged 2–9 years were enrolled in the study. INDT-ASD and Childhood Autism Rating Scale (CARS) were administered in a randomly decided sequence by trained psychologist, followed by an expert evaluation by DSM-IV TR diagnostic criteria (gold standard).

Main outcome measures

Psychometric parameters of diagnostic accuracy, validity (construct, criterion and convergent) and internal consistency.

Results

154 children (110 boys, mean age 64.2 mo) were enrolled. The overall diagnostic accuracy (AUC=0.97, 95% CI 0.93, 0.99; P<0.001) and validity (sensitivity 98%, specificity 95%, positive predictive value 91%, negative predictive value 99%) of INDT-ASD for Autism spectrum disorder were high, taking expert diagnosis using DSM-IV-TR as gold standard. The concordance rate between the INDT-ASD and expert diagnosis for’ ASD group’ was 82.52% [Cohen’s κ=0.89; 95% CI (0.82, 0.97); P=0.001]. The internal consistency of INDT-ASD was 0.96. The convergent validity with CARS (r = 0.73, P= 0.001) and divergent validity with Binet-Kamat Test of intelligence (r = ?0.37; P=0.004) were significantly high. INDT-ASD has a 4-factor structure explaining 85.3% of the variance.

Conclusion

INDT-ASD has high diagnostic accuracy, adequate content validity, good internal consistency high criterion validity and high to moderate convergent validity and 4-factor construct validity for diagnosis of Autistm spectrum disorder.  相似文献   
67.
Most of thoracic surgery developed as a result of efforts to treat tuberculosis (TB). The role of surgical therapy has declined but the role of surgery in TB still remains in situations like diagnostic difficulties, persistent sputum positive state despite therapy and complications and sequel like haemoptysis, destroyed or bronchiectatic lungs or empyema with or without broncho-pleural fistula (BPF). Various procedures have a role according to the indication. Some of the procedures have become obsolete but lobectomy, pneumonectomy, thoracoplasty, decortication and open window thoracostomy continue to be relevant. Recent published series have demonstrated mortality ranging from 0% to 3.1%. Surgery for complications and sequel of pulmonary TB still remain an important intervention for alleviation of human misery.KEYWORDS : Thoracic surgery, tuberculosis (TB), surgery, pneumonectomy, thoracoplasty, decortication, window thoracostomy  相似文献   
68.
69.
Alagille syndrome (ALGS) and progressive familial intrahepatic cholestasis (PFIC) are rare, inherited cholestatic liver disorders that manifest in infants and children and are associated with impaired bile flow (ie cholestasis), pruritus and potentially fatal liver disease. There are no effective or approved pharmacologic treatments for these diseases (standard medical treatments are supportive only), and new, noninvasive options would be valuable. Typically, bile acids undergo biliary secretion and intestinal reabsorption (ie enterohepatic circulation). However, in these diseases, disrupted secretion of bile acids leads to their accumulation in the liver, which is thought to underlie pruritus and liver‐damaging inflammation. One approach to reducing pathologic bile acid accumulation in the body is surgical biliary diversion, which interrupts the enterohepatic circulation (eg by diverting bile acids to an external stoma). These procedures can normalize serum bile acids, reduce pruritus and liver injury and improve quality of life. A novel, nonsurgical approach to interrupting the enterohepatic circulation is inhibition of the ileal bile acid transporter (IBAT), a key molecule in the enterohepatic circulation that reabsorbs bile acids from the intestine. IBAT inhibition has been shown to reduce serum bile acids and pruritus in trials of paediatric cholestatic liver diseases. This review explores the rationale of inhibition of the IBAT as a therapeutic target, describes IBAT inhibitors in development and summarizes the current data on interrupting the enterohepatic circulation as treatment for cholestatic liver diseases including ALGS and PFIC.  相似文献   
70.
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