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   4925403篇
  免费   387602篇
  国内免费   15392篇
耳鼻咽喉   69598篇
儿科学   159875篇
妇产科学   131356篇
基础医学   738622篇
口腔科学   135373篇
临床医学   450988篇
内科学   902401篇
皮肤病学   118161篇
神经病学   410482篇
特种医学   192682篇
外国民族医学   1299篇
外科学   741967篇
综合类   136413篇
现状与发展   24篇
一般理论   2791篇
预防医学   408383篇
眼科学   116594篇
药学   352057篇
  26篇
中国医学   13078篇
肿瘤学   246227篇
  2021年   56814篇
  2019年   59335篇
  2018年   76104篇
  2017年   58315篇
  2016年   64630篇
  2015年   77153篇
  2014年   111463篇
  2013年   177244篇
  2012年   139509篇
  2011年   147323篇
  2010年   130829篇
  2009年   130874篇
  2008年   133286篇
  2007年   143191篇
  2006年   150646篇
  2005年   144757篇
  2004年   145776篇
  2003年   135745篇
  2002年   124891篇
  2001年   196365篇
  2000年   193233篇
  1999年   174339篇
  1998年   75671篇
  1997年   70250篇
  1996年   68277篇
  1995年   63653篇
  1994年   57705篇
  1993年   53498篇
  1992年   128173篇
  1991年   123075篇
  1990年   118805篇
  1989年   115408篇
  1988年   106384篇
  1987年   104297篇
  1986年   98066篇
  1985年   95409篇
  1984年   77417篇
  1983年   68241篇
  1982年   51221篇
  1981年   47513篇
  1980年   44386篇
  1979年   67202篇
  1978年   52459篇
  1977年   46430篇
  1976年   43024篇
  1975年   43939篇
  1974年   48459篇
  1973年   46446篇
  1972年   43476篇
  1971年   40111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.
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   
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