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   3505076篇
  免费   296361篇
  国内免费   15949篇
耳鼻咽喉   47434篇
儿科学   111957篇
妇产科学   91425篇
基础医学   558782篇
口腔科学   94187篇
临床医学   323880篇
内科学   617960篇
皮肤病学   91096篇
神经病学   302175篇
特种医学   135748篇
外国民族医学   393篇
外科学   530823篇
综合类   106478篇
现状与发展   23篇
一般理论   2298篇
预防医学   304080篇
眼科学   79569篇
药学   241202篇
  27篇
中国医学   10520篇
肿瘤学   167329篇
  2021年   55527篇
  2020年   35400篇
  2019年   58452篇
  2018年   72238篇
  2017年   55029篇
  2016年   60627篇
  2015年   74662篇
  2014年   108997篇
  2013年   174655篇
  2012年   99980篇
  2011年   101243篇
  2010年   119331篇
  2009年   122698篇
  2008年   86987篇
  2007年   90341篇
  2006年   100643篇
  2005年   95745篇
  2004年   96900篇
  2003年   87150篇
  2002年   76719篇
  2001年   107637篇
  2000年   100972篇
  1999年   99708篇
  1998年   65779篇
  1997年   63606篇
  1996年   61290篇
  1995年   56899篇
  1994年   51053篇
  1993年   47632篇
  1992年   70941篇
  1991年   68036篇
  1990年   64563篇
  1989年   62953篇
  1988年   58519篇
  1987年   57116篇
  1986年   54536篇
  1985年   54394篇
  1984年   49339篇
  1983年   44950篇
  1982年   42062篇
  1981年   39634篇
  1980年   37261篇
  1979年   40832篇
  1978年   35990篇
  1977年   32516篇
  1976年   30364篇
  1975年   28594篇
  1974年   30088篇
  1973年   28986篇
  1972年   27115篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
Adjuvant irradiation is the standard treatment after breast conservative surgery. Normofractionated regimen with an overall treatment time of 5 to 6 weeks is often considered as a limiting factor for irradiation compliance. In order to answer this issue, moderate and more recently extreme hypofractionated protocols appeared. We report here oncological outcomes and toxicity of hypofractionated breast irradiation. After defining the frame of moderate and extreme hypofractionated breast irradiations based on overall treatment time, patient selection criteria were listed. According to their levels of proof, the results of moderate and extreme hypofractionated breast irradiation were analysed. Overall treatment time for moderate hypofractionated breast irradiation ranged from 3 to 4 weeks, while for extreme hypofractionated breast irradiation, it was less than 1 week. For moderate hypofractionated breast irradiation, whole breast irradiation was currently performed with or without lymph node irradiation. Moderate hypofractionated breast irradiation has proven to be as safe and as efficient as normofractionated breast irradiation with level IA evidence. For extreme hypofractionated breast irradiation, phase III randomized trials confirmed that accelerated partial breast irradiation was non-inferior in terms of local control compared to normofractionated whole breast irradiation (with external beam radiation therapy and multicatheter brachytherapy), with similar acute and late toxicity. While the use of intraoperative breast irradiation remains under debate, new very accelerated partial breast irradiation (overall treatment time not exceeding 2 days) protocols emerged with encouraging results. Accelerated partial breast irradiation is warranted for extreme hypofractionated breast irradiation and is indicated for low-risk breast cancers. Moderate and extreme hypofractionated breast irradiation regimens are validated and can be routinely proposed according to patient selection criteria.  相似文献   
92.
93.
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   

94.
95.
96.
97.
98.
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   
99.
100.
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   
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