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   4725898篇
  免费   386957篇
  国内免费   16022篇
耳鼻咽喉   67507篇
儿科学   149495篇
妇产科学   125024篇
基础医学   714164篇
口腔科学   133463篇
临床医学   432174篇
内科学   858620篇
皮肤病学   112841篇
神经病学   400276篇
特种医学   187584篇
外国民族医学   1155篇
外科学   715733篇
综合类   139153篇
现状与发展   23篇
一般理论   2781篇
预防医学   401703篇
眼科学   112483篇
药学   334862篇
  25篇
中国医学   12386篇
肿瘤学   227425篇
  2021年   56277篇
  2019年   59070篇
  2018年   74855篇
  2017年   57310篇
  2016年   63806篇
  2015年   76525篇
  2014年   111472篇
  2013年   177118篇
  2012年   131458篇
  2011年   137514篇
  2010年   127618篇
  2009年   128964篇
  2008年   123875篇
  2007年   132479篇
  2006年   140848篇
  2005年   135776篇
  2004年   136640篇
  2003年   126880篇
  2002年   116913篇
  2001年   176621篇
  2000年   173784篇
  1999年   158135篇
  1998年   74283篇
  1997年   69761篇
  1996年   67616篇
  1995年   63473篇
  1994年   57599篇
  1993年   53259篇
  1992年   118843篇
  1991年   114236篇
  1990年   109356篇
  1989年   106487篇
  1988年   98567篇
  1987年   97232篇
  1986年   92063篇
  1985年   90169篇
  1984年   74544篇
  1983年   65948篇
  1982年   51171篇
  1981年   47441篇
  1980年   44527篇
  1979年   66608篇
  1978年   52780篇
  1977年   46286篇
  1976年   43249篇
  1975年   43123篇
  1974年   49236篇
  1973年   47239篇
  1972年   44218篇
  1971年   40738篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
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   

92.
93.
94.
95.
96.
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   
97.
98.
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   
99.
We review the spectrum of cutaneous disorders associated with inflammatory and neoplastic plasmacytic pathology. Because plasma cells are derived from B‐lymphocytes our overview includes discussion of certain lymphoplasmacytic proliferations. It is structured along histopathological lines, addressing conditions characterized by (a) cutaneous plasma cell infiltrates, (b) deposits of plasma cell products or their derivatives in the skin and (c) miscellaneous, poorly understood cutaneous complications of plasmacytic disorders. Lesions arising primarily in the skin and those due to cutaneous involvement by multisystem disorders are addressed. The range includes a spectrum of tumefactive and circulatory manifestations. We highlight key clinical and pathological features of the different conditions and outline recent advances in our understanding of these entities. By emphasizing the dermatopathological characteristics of this spectrum of disorders we hope to hone the diagnostic accuracy of practitioners in the field.  相似文献   
100.
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