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   5069970篇
  免费   400558篇
  国内免费   15543篇
耳鼻咽喉   71693篇
儿科学   163850篇
妇产科学   134479篇
基础医学   761551篇
口腔科学   141893篇
临床医学   466079篇
内科学   921669篇
皮肤病学   121178篇
神经病学   415445篇
特种医学   198507篇
外国民族医学   813篇
外科学   769985篇
综合类   144566篇
现状与发展   24篇
一般理论   2826篇
预防医学   425476篇
眼科学   121361篇
药学   360681篇
  24篇
中国医学   13736篇
肿瘤学   250235篇
  2021年   56943篇
  2019年   59427篇
  2018年   76567篇
  2017年   58316篇
  2016年   64723篇
  2015年   76932篇
  2014年   111560篇
  2013年   176973篇
  2012年   144401篇
  2011年   154445篇
  2010年   133162篇
  2009年   131702篇
  2008年   139359篇
  2007年   150256篇
  2006年   157054篇
  2005年   151868篇
  2004年   151861篇
  2003年   141340篇
  2002年   130377篇
  2001年   197549篇
  2000年   194639篇
  1999年   174727篇
  1998年   76311篇
  1997年   70578篇
  1996年   68866篇
  1995年   64293篇
  1994年   58329篇
  1993年   54061篇
  1992年   129393篇
  1991年   125825篇
  1990年   121463篇
  1989年   118245篇
  1988年   109132篇
  1987年   107055篇
  1986年   101302篇
  1985年   98873篇
  1984年   80055篇
  1983年   70487篇
  1982年   52341篇
  1981年   48494篇
  1980年   45629篇
  1979年   71552篇
  1978年   55787篇
  1977年   48501篇
  1976年   45536篇
  1975年   46865篇
  1974年   52925篇
  1973年   50685篇
  1972年   47700篇
  1971年   44335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