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   1398599篇
  免费   103710篇
  国内免费   2135篇
耳鼻咽喉   17863篇
儿科学   44334篇
妇产科学   37192篇
基础医学   207105篇
口腔科学   37680篇
临床医学   131161篇
内科学   275795篇
皮肤病学   30166篇
神经病学   114407篇
特种医学   52822篇
外国民族医学   278篇
外科学   200094篇
综合类   27415篇
现状与发展   3篇
一般理论   670篇
预防医学   114639篇
眼科学   30985篇
药学   101203篇
  7篇
中国医学   2232篇
肿瘤学   78393篇
  2021年   12321篇
  2019年   12667篇
  2018年   16578篇
  2017年   12799篇
  2016年   14063篇
  2015年   16132篇
  2014年   22348篇
  2013年   33362篇
  2012年   46356篇
  2011年   49419篇
  2010年   28534篇
  2009年   27469篇
  2008年   46066篇
  2007年   49092篇
  2006年   48593篇
  2005年   47751篇
  2004年   45473篇
  2003年   43269篇
  2002年   41893篇
  2001年   57783篇
  2000年   58513篇
  1999年   49856篇
  1998年   15039篇
  1997年   13519篇
  1996年   13762篇
  1995年   12974篇
  1994年   12037篇
  1992年   39227篇
  1991年   38595篇
  1990年   37238篇
  1989年   36012篇
  1988年   33406篇
  1987年   32718篇
  1986年   31214篇
  1985年   29468篇
  1984年   22680篇
  1983年   19831篇
  1982年   12147篇
  1979年   21450篇
  1978年   15911篇
  1977年   13211篇
  1976年   12271篇
  1975年   13169篇
  1974年   16011篇
  1973年   15722篇
  1972年   14847篇
  1971年   13805篇
  1970年   13029篇
  1969年   12274篇
  1968年   11422篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
41.
42.
43.
Cutaneous plasmacytosis is a rare disorder characterized by a benign proliferation of mature plasma cells that appears as multiple dark-brown to purplish skin lesions, often associated with polyclonal hypergammaglobulinaemia. We present the case of a 55-year-old Caucasian man who suffered from a cutaneous plasmacytosis associated with two different carcinomas. Cutaneous plasmacytosis seems to be a reactive process because most cases reported are not associated with any apparent underlying disease. Nevertheless, because few reported cases were associated with malignancies, screening of additional neoplasms would be justified.  相似文献   
44.
Cell physiology and molecular biology typically follow a reductionistic approach in science. In the last decade, molecular principles and pathogenetic factors involved in the development of many diseases have been successfully discovered. Therefore, early biological concepts based on systemic and cybernetic thoughts have been largely overshadowed by these more recent molecular and pathogenetic factors. This review highlights discoveries on bone development and hypothalamic controlled feeding and eating behavior with a cybernetic and systemic perspective. Interestingly, ancient ideas on bone development and hypothalamic function are still reasonable considerations to embed new molecular discoveries into a systemic concept of principles organizing nature.  相似文献   
45.
46.
The absence of the temporary incisors could be to a genetic illness or to some multiple premature extractions. These extractions are the aftermaths of the carious lesions or some traumatisms underwent by the temporary incisors. Beyond measure the loss of the space, the premature loss some temporary incisors very often assign the relational development of the child and disturb its psychological development and the aesthetic function. Across some cases clinics, the authors show that the replacement of the temporary incisors is the therapeutic ideal solution. Indeed, the child prosthesis, replacing the temporary absent incisors, solves the psychological, aesthetic and relational problems of the child.  相似文献   
47.
Contour defects resulting in deformity caused by lack of tissue can be improved by conventional surgery using autologous tissue, but there is always a donor site morbidity. Integra has been available since the early 1980's for use in acute burns and more recently in reconstruction. It has been shown histologically to act as a tissue regeneration template. The regenerated dermis is buried under an autologous thin split-skin graft. In this study, the principle of burying Integra (without the silicone layer) has been applied to deep tissue defects in 12 reconstructive cases. Such regenerated tissues survive at least 3 years after burying. Modification to the technique to avoid visible edges are being developed.  相似文献   
48.
49.
50.
There is increasing evidence that the assessment of eosinophilic airway inflammation using induced sputum and measurement of airway hyperresponsiveness provides additional, clinically important information concerning asthma control. The aim of this study was to directly compare the effects of different treatments on these markers in patients with asthma and persistent symptoms, despite the use of low-dose inhaled corticosteroids. A double-blind four-way crossover study was performed, which compared a 1-month treatment with budesonide 400 mug b.i.d., additional formoterol, additional montelukast and placebo in 49 patients with uncontrolled asthma despite budesonide 100 mug b.i.d., with each treatment separated by a 4-week washout period. The change in sputum eosinophil count with formoterol (2.4 to 3.8% change, 0.6-fold reduction, 95% confidence interval (CI) 0.5-0.9) differed significantly from placebo (2.8 to 2.5% change, 1.1-fold reduction, 95% CI 0.7-1.6) and high-dose budesonide (2.7 to 1.6% change, 1.6-fold reduction, 95% CI 1.2-2.2). The effects of montelukast did not differ from placebo. The changes in methacholine airway responsiveness were small and did not differ between treatments. High-dose budesonide had the broadest range of beneficial effects on other outcomes, including symptom scores, morning peak expiratory flow and forced expiratory volume in one second. In conclusion, treatment given in addition to low-dose inhaled corticosteroids results in modest benefits. Formoterol and high-dose budesonide have contrasting effects on eosinophilic airway inflammation.  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