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   446篇
  免费   22篇
  国内免费   5篇
耳鼻咽喉   9篇
儿科学   6篇
妇产科学   6篇
基础医学   83篇
口腔科学   6篇
临床医学   34篇
内科学   63篇
皮肤病学   13篇
神经病学   42篇
特种医学   11篇
外科学   53篇
综合类   2篇
预防医学   72篇
眼科学   4篇
药学   21篇
肿瘤学   48篇
  2023年   5篇
  2022年   28篇
  2021年   26篇
  2020年   10篇
  2019年   14篇
  2018年   20篇
  2017年   17篇
  2016年   13篇
  2015年   13篇
  2014年   13篇
  2013年   28篇
  2012年   36篇
  2011年   46篇
  2010年   27篇
  2009年   25篇
  2008年   25篇
  2007年   15篇
  2006年   24篇
  2005年   20篇
  2004年   11篇
  2003年   15篇
  2002年   11篇
  2001年   3篇
  2000年   3篇
  1999年   4篇
  1998年   2篇
  1997年   1篇
  1995年   1篇
  1993年   2篇
  1992年   2篇
  1991年   6篇
  1988年   5篇
  1986年   1篇
  1962年   1篇
排序方式: 共有473条查询结果,搜索用时 0 毫秒
61.
Cervical spondylolysis is defined as a corticated cleft between the superior and inferior articular facets of the articular pillar, the cervical equivalent of the pars interarticularis in the lumbar spine. Of primary importance is its recognition to avoid confusion with more clinically significant abnormalities such as fracture or dislocation. This case report describes bilateral spondylolysis and associated dysplasia of C5 in a 31-year-old female. We describe the radiographic presentation of this anomaly, stressing the importance of computed tomography for correct diagnosis. A review of the literature on this interesting abnormality and a complete differential diagnosis are presented.  相似文献   
62.
Myofibroblastic inflammatory tumor is considered as an intermediate neoplasm according to the WHO classification. It can occur in different organs: lung, pancreas, mesentery and uterus. The localization in the bladder is unusual. We report a case of a 38-year-old patient who presented with hematuria. Echography showed a 3 cm tissular structure of the bladder. Histological analysis and immunohistochemistry concluded to the diagnosis of myofibroblastic tumor of the bladder. The present work will give a general view of the myofibroblastic tumor, and will review its differential diagnosis.  相似文献   
63.
64.
Reactivity to traumatic stress varies between individuals and only a minority of those exposed to trauma develops stress-induced psychopathologies. Currently extensive effort is made to unravel the specific mechanisms predisposing to vulnerability vs. resilience to stress. We investigated in rats the role of β-endorphin metabolism in vulnerability to acute traumatic stress. Responders (showing extreme anxiety; n=7) and resilient non-responders (not differing from the non-stressed individuals; n=8) to traumatic foot-shock stress were compared for their blood levels of stress hormones as well as brain levels and activity of two opioid-degrading enzymes. β-endorphin is a substrate to insulin degrading enzyme, which also degrades insulin. Therefore, the effects of insulin application on behavioral and hormonal responses and on β-endorphin degradation were tested. Pre- and post-stress levels of serum corticosterone, and post-stress plasma β-endorphin concentration differentiated between the responders and the non-responders. In brain, responders showed enhanced degradation rates of β-endorphin, assessed by Liquid Chromatography–Tandem Mass Spectrometry (LC-MS/MS), in hippocampal and amygdalar slices as compared to non-responders. Application of insulin to the amygdala, prior to exposure to traumatic stress, reduced post-stress anxiety and serum corticosterone levels only in the responders. In parallel, amygdalar β-endorphin degradation rate was also reduced by insulin. These results suggest that slowing down β-endorphin degradation rate may constitute an integral part of the normal stress-response, upon a failure of which an extreme anxiety develops. Modulation of opioid degradation may thus present a potential novel target for interference with extreme anxiety.  相似文献   
65.
66.
The clinical syndrome of pure akinesia (PA) is considered the third phenotype of progressive supranuclear palsy (PSP), and is characterized by freezing of gait and prominent speech disturbance without rigidity or tremor. It is frequently considered one of the dopamine resistant motor syndromes, and its pathophysiology remains unclear. We report a patient followed in the Department of Neurology of Razi Hospital, Tunisia, with PA with gait freezing (PAGF) with a frontal hypoperfusion on single photon emission CT and non-responsive dopa therapy. We discuss the clinical features of PAGF and efficiency of treatment options.  相似文献   
67.
68.
69.
Methicillin-resistant Staphylococcus aureus (MRSA) is often the severe causal agent in nosocomial infections that are becoming increasingly difficult to cure because of emerging resistance to all current antibiotic classes. Geographic spread of several MRSA clones between countries and continents has been reported and proven by molecular evidence. Several strains have been isolated from patients in the community without established risk factors for MRSA acquisition. Some of them may have origins in the hospital but others appear to be community-acquired strains. Community MRSA strains have several distinguishing characteristics that may enable them to more readily colonize and infect otherwise healthy hosts. Molecular typing approaches have been used with great advantage in studying of the MRSA epidemiology. It appears that a complete characterization of MRSA requires not only identification of the genetic background of the bacteria but also identification of the structural types of Staphylococcal Cassette Chromosome mec element (SCCmec), which carries methicillin resistance determinant mecA. Rapid and precise identification of MRSA is a prerequisite for control of hospital infections. This article reviews recent publications addressing the epidemiology markers of MRSA, specially of community-acquired strains, and the genetic diversity of SCCmec for identifying MRSA. It appears that MRSA will be an increasing important pathogen in the community.  相似文献   
70.
Human infertility is a healthcare problem that has a worldwide impact. Genetic causes of human infertility include chromosomal aneuploidies and rearrangements and single-gene defects. The sex chromosomes (X and Y) are critical players in human fertility since they contain several genes essential for sex determination and reproductive traits for both men and women. This paper provides a review of the most common sex chromosomes-linked single-gene disorders involved in human infertility and their corresponding phenotypes. In addition to the Y-linked SRY gene, which mutations may cause XY gonadal dysgenesis and sex reversal, the deletions of genes present in AZF regions of the Y chromosome (DAZ, RBMY, DBY and USP9Y genes) are implicated in varying degrees of spermatogenic dysfunction. Furthermore, a list of X-linked genes (KAL1, NR0B1, AR, TEX11, FMR1, PGRMC1, BMP15 and POF1 and 2 regions genes (XPNPEP2, POF1B, DACH2, CHM and DIAPH2)) were reported to have critical roles in pubertal and reproductive deficiencies in humans, affecting only men, only women or both sexes. Mutations in these genes may be transmitted to the offspring by a dominant or a recessive inheritance.  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