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   1520566篇
  免费   102948篇
  国内免费   4266篇
耳鼻咽喉   18169篇
儿科学   50491篇
妇产科学   39662篇
基础医学   217654篇
口腔科学   37530篇
临床医学   142221篇
内科学   291291篇
皮肤病学   27165篇
神经病学   128516篇
特种医学   57543篇
外国民族医学   366篇
外科学   216441篇
综合类   31489篇
现状与发展   1篇
一般理论   461篇
预防医学   132207篇
眼科学   31745篇
药学   108778篇
  6篇
中国医学   3783篇
肿瘤学   92261篇
  2021年   10991篇
  2019年   11727篇
  2018年   38330篇
  2017年   29904篇
  2016年   33984篇
  2015年   16195篇
  2014年   21618篇
  2013年   32802篇
  2012年   51028篇
  2011年   67932篇
  2010年   45584篇
  2009年   36761篇
  2008年   63323篇
  2007年   69104篇
  2006年   45676篇
  2005年   46232篇
  2004年   45816篇
  2003年   45427篇
  2002年   42071篇
  2001年   61273篇
  2000年   63229篇
  1999年   52539篇
  1998年   14847篇
  1997年   13622篇
  1996年   13275篇
  1995年   12635篇
  1994年   11826篇
  1993年   11078篇
  1992年   41695篇
  1991年   40930篇
  1990年   39615篇
  1989年   37473篇
  1988年   34701篇
  1987年   33826篇
  1986年   32254篇
  1985年   30742篇
  1984年   23107篇
  1983年   19661篇
  1982年   11839篇
  1979年   20900篇
  1978年   14879篇
  1977年   12083篇
  1976年   11943篇
  1975年   12115篇
  1974年   14836篇
  1973年   14481篇
  1972年   13356篇
  1971年   12418篇
  1970年   11520篇
  1969年   10453篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
Annals of Nuclear Medicine - The Response Evaluation Criteria In Solid Tumors (RECIST) is the most used radiological method for evaluating response after peptide receptor radionuclide therapy...  相似文献   
83.
84.
85.
86.
Porocarcinoma is an unusual, locally aggressive and potentially fatal neoplasm. Several cutaneous malignancies have been described in association with porocarcinoma, including squamous cell carcinoma, basal cell carcinoma and tricholemmal carcinoma. Previous reports have indicated that the occurrence of malignant tumours in combination with porocarcinoma is extremely rare, in particular with regard to Bowen disease (BD). We report an uncommon case of porocarcinoma occurring synchronously in a single BD lesion in a 63‐year‐old woman with multiple BD lesions. The clinical and histological findings confirmed this diagnosis.  相似文献   
87.
Reactive lymphoid infiltrates of the skin composed predominantly of gamma‐delta (γδ) T cells are not well described in the literature. Herein we report a case of an otherwise healthy 4‐year‐old male who presented with a waxing and waning papular rash characterized by small, discrete crusted papules spread across his trunk, face and extremities. Clinical evaluation revealed no evidence of systemic disease. Microscopic examination revealed a dermal, perivascular infiltrate of highly atypical lymphocytes with a γδ T cell phenotype, worrisome for primary cutaneous γδ T cell lymphoma. The clinical course, however, was that of a reactive condition and prompted consideration of a diagnosis of pityriasis lichenoides et varioliformis acuta (PLEVA) and lymphomatoid papulosis (LyP). In many ways, this case defies current classification schemes and seems to expand the spectrum of reactive γδ T cell infiltrates of the skin.  相似文献   
88.
89.
In the 6th Basic Plan for Long-Term Electricity Supply and Demand (6th BPE) for Korea, for the first time, the environmental costs of air pollution caused by oxides of sulfur (SOx), oxides of nitrogen (NOx), and particulate matters (PM) from power plants were estimated and included. However, several deficiencies in evaluating the environmental costs were found. In this study, (1) the validity of the environmental costs used in the 6th BPE was assessed, (2) a systematic approach was suggested and used to improve the environmental costs estimation, and (3) the sensitivity of the cost of generating electricity to the environmental costs by fuel type with the proposed approach was discussed. We found that the applied environmental costs used in the 6th BPE did not fully include the demographic characteristics of Korea. By applying more realistic parameter values, it was found that the newly estimated environmental cost was about 23 times higher than the cost estimated in the original 6th BPE for coal-fired power plants and about 1.5 times higher for liquefied natural gas (LNG)-fired power plants, suggesting that LNG-fired power plants are more economical if using more realistic environmental costs. Thus, it is critical to check the validity of parameter values when calculating environmental costs.  相似文献   
90.
Bowel diseases of prematurity, including necrotizing enterocolitis, are dreaded ailments of neonates. Early diagnosis is difficult, with clinical and radiographic findings often inconclusive. We present a novel use of contrast-enhanced ultrasound in detection of pediatric bowel disease. Early identification of compromised blood flow or an at-risk bowel can be quantitatively detected and monitored. This ability has implications for guidance of emerging therapies, allowing targeting of inflammation. These findings represent an advancement in detection of bowel disease in neonates.  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