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   3552308篇
  免费   297828篇
  国内免费   13652篇
耳鼻咽喉   48132篇
儿科学   112468篇
妇产科学   91952篇
基础医学   563025篇
口腔科学   95481篇
临床医学   326132篇
内科学   630516篇
皮肤病学   93021篇
神经病学   306260篇
特种医学   139240篇
外国民族医学   301篇
外科学   543637篇
综合类   103875篇
现状与发展   25篇
一般理论   2484篇
预防医学   301615篇
眼科学   81335篇
药学   244155篇
  23篇
中国医学   9560篇
肿瘤学   170551篇
  2021年   56249篇
  2020年   35809篇
  2019年   59064篇
  2018年   73085篇
  2017年   55402篇
  2016年   61110篇
  2015年   74930篇
  2014年   109570篇
  2013年   175457篇
  2012年   105754篇
  2011年   107640篇
  2010年   120948篇
  2009年   124480篇
  2008年   93517篇
  2007年   98099篇
  2006年   107248篇
  2005年   102823篇
  2004年   103765篇
  2003年   93688篇
  2002年   83153篇
  2001年   103124篇
  2000年   95650篇
  1999年   95745篇
  1998年   65196篇
  1997年   63082篇
  1996年   61105篇
  1995年   56510篇
  1994年   50772篇
  1993年   47411篇
  1992年   67782篇
  1991年   65019篇
  1990年   61598篇
  1989年   60786篇
  1988年   56580篇
  1987年   55348篇
  1986年   52783篇
  1985年   52394篇
  1984年   48319篇
  1983年   44470篇
  1982年   41864篇
  1981年   39569篇
  1980年   37278篇
  1979年   40756篇
  1978年   36356篇
  1977年   32915篇
  1976年   30212篇
  1975年   29068篇
  1974年   30554篇
  1973年   29666篇
  1972年   27900篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
102.
103.
104.
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   
105.
106.
107.
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   
108.
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   
109.
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   
110.
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