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   4375482篇
  免费   366112篇
  国内免费   15583篇
耳鼻咽喉   62038篇
儿科学   135909篇
妇产科学   114104篇
基础医学   668042篇
口腔科学   121096篇
临床医学   398892篇
内科学   796108篇
皮肤病学   104861篇
神经病学   377165篇
特种医学   174954篇
外国民族医学   925篇
外科学   667815篇
综合类   127437篇
现状与发展   24篇
一般理论   2688篇
预防医学   368781篇
眼科学   103323篇
药学   309447篇
  23篇
中国医学   11552篇
肿瘤学   211993篇
  2021年   56957篇
  2020年   36244篇
  2019年   59707篇
  2018年   74888篇
  2017年   56828篇
  2016年   63439篇
  2015年   76461篇
  2014年   111713篇
  2013年   177815篇
  2012年   127146篇
  2011年   131334篇
  2010年   126406篇
  2009年   128946篇
  2008年   117522篇
  2007年   124945篇
  2006年   133833篇
  2005年   128877篇
  2004年   129353篇
  2003年   119421篇
  2002年   109713篇
  2001年   154886篇
  2000年   150939篇
  1999年   140034篇
  1998年   71888篇
  1997年   68209篇
  1996年   65977篇
  1995年   61815篇
  1994年   55905篇
  1993年   51899篇
  1992年   103796篇
  1991年   99173篇
  1990年   94218篇
  1989年   91871篇
  1988年   85466篇
  1987年   83920篇
  1986年   79610篇
  1985年   78070篇
  1984年   66114篇
  1983年   59005篇
  1982年   48295篇
  1981年   45015篇
  1980年   42293篇
  1979年   57922篇
  1978年   47127篇
  1977年   41677篇
  1976年   38738篇
  1975年   37913篇
  1974年   42478篇
  1973年   40611篇
  1972年   38061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