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   3286487篇
  免费   282846篇
  国内免费   13947篇
耳鼻咽喉   44916篇
儿科学   105190篇
妇产科学   83780篇
基础医学   529381篇
口腔科学   88350篇
临床医学   297213篇
内科学   576454篇
皮肤病学   89242篇
神经病学   284376篇
特种医学   129327篇
外国民族医学   330篇
外科学   510248篇
综合类   101165篇
现状与发展   23篇
一般理论   2417篇
预防医学   278377篇
眼科学   75009篇
药学   224144篇
  23篇
中国医学   9415篇
肿瘤学   153900篇
  2021年   55864篇
  2020年   35589篇
  2019年   58743篇
  2018年   72008篇
  2017年   54888篇
  2016年   60569篇
  2015年   74582篇
  2014年   109003篇
  2013年   174497篇
  2012年   92352篇
  2011年   92352篇
  2010年   117285篇
  2009年   121379篇
  2008年   78446篇
  2007年   80632篇
  2006年   91517篇
  2005年   86687篇
  2004年   88553篇
  2003年   79264篇
  2002年   68686篇
  2001年   94660篇
  2000年   87138篇
  1999年   88878篇
  1998年   64517篇
  1997年   62511篇
  1996年   60244篇
  1995年   55807篇
  1994年   50042篇
  1993年   46600篇
  1992年   62463篇
  1991年   59588篇
  1990年   56690篇
  1989年   56055篇
  1988年   51715篇
  1987年   51122篇
  1986年   48233篇
  1985年   48749篇
  1984年   45360篇
  1983年   41631篇
  1982年   40745篇
  1981年   38562篇
  1980年   36248篇
  1979年   37113篇
  1978年   33793篇
  1977年   31004篇
  1976年   28498篇
  1975年   26849篇
  1974年   27625篇
  1973年   26573篇
  1972年   24691篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Introduction: Percutaneous renal mass biopsy has evolved over the last decade with improvements on previous pitfalls including low tissue yield, high non-diagnostic rates, and complications. As understanding of tumor biology and natural history of renal cortical neoplasms has improved, percutaneous renal mass biopsy is poised to have an expanding role in an area characterized by individualized management and refined risk stratification.

Areas covered: This review summarizes the evolution of renal mass biopsy to its current state with respect to outcomes, indications, and clinical guidelines.

Expert opinion: With improved understanding of differential biological potential of renal cortical neoplasms combined with technical improvements in diagnostic yield and accuracy, utilization of renal mass biopsy is becoming an important adjunct to patient care in a broad range of clinical scenarios, including active surveillance, thermal ablation, and use of primary systemic therapy in localized and advanced settings.  相似文献   

102.
103.
104.
105.
106.
MicroRNAs (miRNAs) play important roles in prostate cancer development. However, it remains unclear how individual miRNAs contribute to the initiation and progression of prostate cancer. Here we show that a basal layer‐enriched miRNA is required for prostate tumorigenesis. We identify miR‐205 as the most highly expressed miRNA and enriched in the basal cells of the prostate. Although miR‐205 is not required for normal prostate development and homeostasis, genetic deletion of miR‐205 in a Pten null tumor model significantly compromises tumor progression and does not promote metastasis. In Pten null basal cells, loss of miR‐205 attenuates pAkt levels and promotes cellular senescence. Furthermore, although overexpression of miR‐205 in prostate cancer cells with luminal phenotypes inhibits cell growth in both human and mouse, miR‐205 has a minimal effect on the growth of a normal human prostate cell line. Taken together, we have provided genetic evidence for a requirement of miR‐205 in the progression of Pten null‐induced prostate cancer.  相似文献   
107.
108.
109.
Secondary tricuspid regurgitation (TR) caused by right ventricular enlargement in the setting of left heart disease/pulmonary hypertension has been well described. In contrast, that associated with right atrial enlargement—atrial functional TR (AF‐TR)—remains largely underappreciated. AF‐TR most often occurs in the setting of lone atrial fibrillation, although it is also seen in its absence (idiopathic AF‐TR). Several recent studies have found that the prevalence, hemodynamic significance, and prognosis of AF‐TR are not inconsequential, suggesting increased physician awareness of this novel clinical entity is warranted. This article discusses the pathogenesis, echocardiographic findings, and treatment of this underappreciated cause of secondary TR.  相似文献   
110.
Among the chief limitations in achieving early detection and control of animal‐origin influenza of pandemic potential in high‐risk livestock populations is the existing lag time between sample collection and diagnostic result. Advances in molecular diagnostics are permitting deployment of affordable, rapid, highly sensitive, and specific point‐of‐capture assays, providing opportunities for targeted surveillance driving containment strategies with potentially compelling returns on investment. Interrupting disease transmission at source holds promise of disrupting cycles of animal‐origin influenza incursion to endemicity and limiting impact on animal production, food security, and public health. Adoption of new point‐of‐capture diagnostics should be undertaken in the context of promoting robust veterinary services systems and parallel support for operationalizing pre‐authorized plans and communication strategies that will ensure that the full potential of these new platforms is realized.  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