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   4248451篇
  免费   343288篇
  国内免费   14026篇
耳鼻咽喉   59160篇
儿科学   135886篇
妇产科学   111056篇
基础医学   656894篇
口腔科学   114595篇
临床医学   385913篇
内科学   767829篇
皮肤病学   106729篇
神经病学   354176篇
特种医学   165293篇
外国民族医学   503篇
外科学   654383篇
综合类   119648篇
现状与发展   23篇
一般理论   2711篇
预防医学   353795篇
眼科学   99706篇
药学   297336篇
  23篇
中国医学   11389篇
肿瘤学   208717篇
  2021年   56678篇
  2020年   36027篇
  2019年   59180篇
  2018年   74768篇
  2017年   56752篇
  2016年   62891篇
  2015年   75767篇
  2014年   110404篇
  2013年   175806篇
  2012年   125254篇
  2011年   131228篇
  2010年   126965篇
  2009年   127777篇
  2008年   116701篇
  2007年   124053篇
  2006年   132660篇
  2005年   127788篇
  2004年   127617篇
  2003年   117839篇
  2002年   106710篇
  2001年   149891篇
  2000年   144685篇
  1999年   134514篇
  1998年   70295篇
  1997年   66362篇
  1996年   64536篇
  1995年   59824篇
  1994年   53883篇
  1993年   50128篇
  1992年   96152篇
  1991年   92770篇
  1990年   89168篇
  1989年   86928篇
  1988年   80129篇
  1987年   78612篇
  1986年   73958篇
  1985年   73098篇
  1984年   61754篇
  1983年   55510篇
  1982年   46079篇
  1981年   43183篇
  1980年   40539篇
  1979年   53161篇
  1978年   44070篇
  1977年   38936篇
  1976年   36308篇
  1975年   36330篇
  1974年   39465篇
  1973年   37683篇
  1972年   35300篇
排序方式: 共有10000条查询结果,搜索用时 78 毫秒
101.
102.
103.
104.
105.
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   
106.
107.
108.
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   
109.
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   
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