首页 | 官方网站   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   321篇
  免费   17篇
医药卫生   338篇
  2024年   2篇
  2023年   3篇
  2022年   5篇
  2021年   16篇
  2020年   8篇
  2019年   12篇
  2018年   8篇
  2017年   8篇
  2016年   7篇
  2015年   5篇
  2014年   8篇
  2013年   16篇
  2012年   28篇
  2011年   47篇
  2010年   15篇
  2009年   16篇
  2008年   24篇
  2007年   20篇
  2006年   21篇
  2005年   20篇
  2004年   15篇
  2003年   10篇
  2002年   6篇
  2001年   2篇
  1999年   2篇
  1998年   2篇
  1997年   3篇
  1994年   1篇
  1992年   1篇
  1991年   1篇
  1985年   2篇
  1982年   2篇
  1981年   2篇
排序方式: 共有338条查询结果,搜索用时 0 毫秒
61.
Intramedullary (IM) nailing is currently the most common method for treating patients with impending pathologic humeral fractures; however, this treatment is associated with known complications primarily owing to violation of the rotator cuff during insertion. A better option is needed. To determine if a humeral segmental replacement prosthesis would provide a stronger construct compared with an IM nail in this setting, we compared the mechanical properties of these two devices in a cadaver model simulating an impending pathologic fracture. In each of nine matched pairs of fresh human humeri one was randomly selected to undergo a 50% lateral middiaphyseal defect simulating an impending pathologic fracture and subsequent fixation with an IM nail and bone cement. The contralateral humerus underwent fixation using a humeral segmental defect prosthesis. We determined T-scores using DEXA. Each specimen subsequently was tested in torsion to failure. Peak torque and peak rotation at failure were greater for the prosthesis specimens whereas torsional stiffness was greater for the IM nail specimens. We found a linear relationship between peak torque and T-score for each device with the slopes of the lines suggesting the construct with the prosthesis can withstand greater forces than the IM nail and the differences between devices were greater in weaker bones.  相似文献   
62.
We used optimized DNA expression vectors to compare two gene delivery methodologies in rhesus macaques, namely direct DNA injection and in vivo adaptive constant-current electroporation via the intramuscular route. The use of in vivo electroporation increased levels of gene expression and immune responses. We used an optimized HIV gag expression plasmid to show the development of new cellular immune responses in SIV-infected animals controlling viremia. Furthermore, after vaccination with SIV expression plasmids the recall responses to the SIV antigens were very high, indicating that DNA is a strong boost in the presence of antiretroviral treatment in SIV-infected animals. There was substantial animal-to-animal variability in DNA expression, revealed by plasma measurements of IL-15 produced by co-injected IL-15 DNA. IL-15 expression levels correlated with peak immune responses. Electroporation led to an expansion of antigen-specific CD4+ and CD8+ T cells of both central and effector memory phenotype. These results indicate that improved gene delivery and expression by electroporation dramatically increases immunogenicity of DNA vaccines. Electroporation is thus an important method to improve the effectiveness of DNA vaccination.  相似文献   
63.
64.
65.
Introduction: In non-exacerbation chronic obstructive pulmonary disease (COPD) with mild lung function impairment, single bronchodilator therapy might be as effective as combined inhaled corticosteroid/bronchodilator therapy, whereas the risk of pneumonia associated with the latter would be practically absent.

Areas covered: We performed an analysis of a recent study evaluating the efficacy and safety of inhaled indacaterol versus inhaled salmeterol/fluticasone in COPD patients.

Expert opinion: Both therapies were found to exert comparable effects on lung function, symptom severity and health status.  相似文献   

66.
The need to recycle and develop nanomaterials from waste, and use them in environmental applications has become increasingly imperative in recent decades. A new method to convert the mill scale, a waste of the steel industry that contains large quantity of iron and low impurities into a nanoadsorbent that has the necessary properties to be used for water purification is presented. The mill scale waste was used as raw material for iron oxide nanopowder. A thorough characterization was performed in each stage of the conversion process from the mill scale powder to magnetic nanopowder including XRD (X-ray diffraction), SEM (scanning electron microscopy), TEM (transmission electron microscopy), BET (Brunauer, Emmett and Teller) and magnetization properties. Iron oxide nanoparticles were approximately 5–6 nm with high specific surface area and good magnetic properties. These are the necessary properties that a magnetic nanopowder must have in order to be used as nanoadsorbents in the heavy metal removal from waters. The iron oxide nanoparticles were evaluated as adsorbents for the removal of Cu, Cd and Ni ions.  相似文献   
67.
68.
69.
Joubert syndrome (JS) is a recessive neurodevelopmental disorder characterized by a distinctive mid‐hindbrain malformation. JS is part of a group of disorders called ciliopathies based on their overlapping phenotypes and common underlying pathophysiology linked to primary cilium dysfunction. Biallelic mutations in one of 28 genes, all encoding proteins localizing to the primary cilium or basal body, can cause JS. Despite this large number of genes, the genetic cause can currently be determined in about 62% of individuals with JS. To identify novel JS genes, we performed whole exome sequencing on 35 individuals with JS and found biallelic rare deleterious variants (RDVs) in KIAA0586, encoding a centrosomal protein required for ciliogenesis, in one individual. Targeted next‐generation sequencing in a large JS cohort identified biallelic RDVs in eight additional families for an estimated prevalence of 2.5% (9/366 JS families). All affected individuals displayed JS phenotypes toward the mild end of the spectrum.  相似文献   
70.
Forty-eight-year old woman with left-sided mastectomy due tobreast cancer received radiotherapy (RT) to the chest wall bya direct electron field. The internal mammary and medial supraclavicularlymph  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-23

京公网安备 11010802026262号