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   3984478篇
  免费   334037篇
  国内免费   14214篇
耳鼻咽喉   54824篇
儿科学   127509篇
妇产科学   104845篇
基础医学   616990篇
口腔科学   109821篇
临床医学   358447篇
内科学   715770篇
皮肤病学   100340篇
神经病学   339837篇
特种医学   160001篇
外国民族医学   551篇
外科学   616544篇
综合类   119709篇
现状与发展   24篇
一般理论   2606篇
预防医学   328617篇
眼科学   93220篇
药学   279891篇
  19篇
中国医学   10783篇
肿瘤学   192381篇
  2021年   56653篇
  2020年   36051篇
  2019年   59360篇
  2018年   74078篇
  2017年   56155篇
  2016年   62312篇
  2015年   75764篇
  2014年   110670篇
  2013年   176673篇
  2012年   113550篇
  2011年   116540篇
  2010年   123795篇
  2009年   126534篇
  2008年   102791篇
  2007年   108250篇
  2006年   117735篇
  2005年   112753篇
  2004年   114607篇
  2003年   104046篇
  2002年   93419篇
  2001年   130171篇
  2000年   124571篇
  1999年   119412篇
  1998年   68572篇
  1997年   65626篇
  1996年   63515篇
  1995年   59041篇
  1994年   53231篇
  1993年   49651篇
  1992年   88336篇
  1991年   85093篇
  1990年   81543篇
  1989年   80100篇
  1988年   74376篇
  1987年   72952篇
  1986年   69544篇
  1985年   69185篇
  1984年   59581篇
  1983年   53772篇
  1982年   45832篇
  1981年   42820篇
  1980年   40341篇
  1979年   51853篇
  1978年   42795篇
  1977年   38306篇
  1976年   35513篇
  1975年   34658篇
  1974年   37712篇
  1973年   36449篇
  1972年   33850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