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   3411403篇
  免费   294843篇
  国内免费   14452篇
耳鼻咽喉   47257篇
儿科学   101951篇
妇产科学   84446篇
基础医学   536330篇
口腔科学   92143篇
临床医学   312896篇
内科学   606360篇
皮肤病学   92836篇
神经病学   295789篇
特种医学   134516篇
外国民族医学   118篇
外科学   547016篇
综合类   98080篇
现状与发展   92篇
一般理论   2279篇
预防医学   276737篇
眼科学   79030篇
药学   234205篇
  24篇
中国医学   9779篇
肿瘤学   168814篇
  2022年   23825篇
  2021年   56956篇
  2020年   37955篇
  2019年   59611篇
  2018年   75259篇
  2017年   58067篇
  2016年   64109篇
  2015年   78176篇
  2014年   115387篇
  2013年   180984篇
  2012年   98187篇
  2011年   98013篇
  2010年   122373篇
  2009年   128131篇
  2008年   84836篇
  2007年   86847篇
  2006年   98481篇
  2005年   92918篇
  2004年   93886篇
  2003年   83979篇
  2002年   73687篇
  2001年   104407篇
  2000年   96840篇
  1999年   97030篇
  1998年   66490篇
  1997年   64061篇
  1996年   61369篇
  1995年   56735篇
  1994年   50442篇
  1993年   47036篇
  1992年   66864篇
  1991年   63285篇
  1990年   59641篇
  1989年   59255篇
  1988年   54603篇
  1987年   53298篇
  1986年   50216篇
  1985年   50609篇
  1984年   46201篇
  1983年   42555篇
  1982年   40765篇
  1981年   38415篇
  1980年   36117篇
  1979年   37032篇
  1978年   33186篇
  1977年   30945篇
  1976年   27742篇
  1975年   26271篇
  1974年   26656篇
  1973年   25325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