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   4980531篇
  免费   394771篇
  国内免费   14777篇
耳鼻咽喉   70273篇
儿科学   161120篇
妇产科学   133777篇
基础医学   748054篇
口腔科学   139781篇
临床医学   454316篇
内科学   905948篇
皮肤病学   119653篇
神经病学   410964篇
特种医学   195430篇
外国民族医学   915篇
外科学   757882篇
综合类   142526篇
现状与发展   23篇
一般理论   2867篇
预防医学   416778篇
眼科学   119021篇
药学   354484篇
  26篇
中国医学   12731篇
肿瘤学   243510篇
  2021年   56457篇
  2019年   58886篇
  2018年   75524篇
  2017年   57871篇
  2016年   64226篇
  2015年   76636篇
  2014年   111160篇
  2013年   176510篇
  2012年   140266篇
  2011年   148949篇
  2010年   131084篇
  2009年   130662篇
  2008年   135023篇
  2007年   145049篇
  2006年   152731篇
  2005年   147776篇
  2004年   148199篇
  2003年   137491篇
  2002年   127033篇
  2001年   187712篇
  2000年   184986篇
  1999年   167290篇
  1998年   74861篇
  1997年   69772篇
  1996年   68018篇
  1995年   63354篇
  1994年   57460篇
  1993年   53389篇
  1992年   125318篇
  1991年   121660篇
  1990年   117560篇
  1989年   114551篇
  1988年   106089篇
  1987年   104145篇
  1986年   98809篇
  1985年   96846篇
  1984年   78600篇
  1983年   69704篇
  1982年   52081篇
  1981年   48309篇
  1980年   45435篇
  1979年   70836篇
  1978年   55367篇
  1977年   48194篇
  1976年   45333篇
  1975年   46241篇
  1974年   52464篇
  1973年   50409篇
  1972年   47150篇
  1971年   44108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