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   1474篇
  免费   153篇
  国内免费   2篇
耳鼻咽喉   3篇
儿科学   33篇
妇产科学   24篇
基础医学   228篇
口腔科学   6篇
临床医学   290篇
内科学   327篇
皮肤病学   16篇
神经病学   106篇
特种医学   44篇
外科学   135篇
综合类   27篇
一般理论   1篇
预防医学   180篇
眼科学   43篇
药学   107篇
中国医学   2篇
肿瘤学   57篇
  2023年   12篇
  2022年   13篇
  2021年   28篇
  2020年   15篇
  2019年   27篇
  2018年   24篇
  2017年   25篇
  2016年   24篇
  2015年   38篇
  2014年   31篇
  2013年   61篇
  2012年   94篇
  2011年   101篇
  2010年   53篇
  2009年   53篇
  2008年   87篇
  2007年   97篇
  2006年   80篇
  2005年   91篇
  2004年   73篇
  2003年   60篇
  2002年   63篇
  2001年   28篇
  2000年   42篇
  1999年   27篇
  1998年   16篇
  1997年   14篇
  1995年   8篇
  1994年   10篇
  1993年   9篇
  1992年   10篇
  1991年   13篇
  1990年   15篇
  1989年   16篇
  1988年   25篇
  1987年   15篇
  1986年   17篇
  1985年   14篇
  1984年   13篇
  1983年   11篇
  1981年   8篇
  1980年   9篇
  1979年   8篇
  1978年   8篇
  1976年   8篇
  1973年   8篇
  1970年   12篇
  1968年   7篇
  1966年   8篇
  1962年   6篇
排序方式: 共有1629条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
Disordered vergence control in dyslexic children.   总被引:4,自引:1,他引:3       下载免费PDF全文
By means of a synoptophore vergence eye movements were recorded in dyslexic and normal children while they were attempting to track small targets moving in simulated depth. Of the dyslexic children 64% were unable to make proper vergence movements when macular sized fusion targets (2 1/2 degrees) were employed, but their vergence control was better for larger (7 degrees) targets. The normal readers and the remaining dyslexics showed normal vergence responses for both large and small moving fusion stimuli. The results suggest that many dyslexics suffer a disorder of visuomotor control and perception for stimuli falling on the macula; this may explain their characteristic visual problems when reading. Hence recording vergence eye movement responses to small moving fusion stimuli may be useful in the investigation and treatment of children with reading difficulties.  相似文献   
5.
This study is concerned with the nature and distribution of mineral in the gallbladder of a patient with chronic cholecystitis. Light and electron microscopic imaging revealed the mineral to be in the epithelial cells of the mucosa and fibroblasts of the submucosa. In the epithelial cells at the early stages of deposition, mineral was located in the nuclei and throughout the cytoplasm in association with interdigitating cell processes and apical microvilli but was absent in mitochondria. Elemental and electron diffraction analyses indicated the mineral inclusions to be apatite in nature.  相似文献   
6.
7.
8.
Musculo-fibrous anomaly in Barrett's mucosa with dysplasia   总被引:1,自引:0,他引:1  
We investigated the histological alterations occurring in the muscularis mucosae, the lamina propria mucosae, and the submucosa in areas adjacent to invasive adenocarcinoma in 32 resected esophagi with Barrett's mucosa. In 26 of the 32 specimens, we observed a thickening of the muscularis mucosae, with overgrowth of the muscle fibers into the lamina propria mucosae. In other areas, collagen-rich fibrotic tissue replaced the muscularis mucosae, the lamina propria mucosae, and even the submucosa. In 31 of the 32 specimens, we noted cystic dilatations of the esophageal glands. Normal esophageal glands and cystically dilated glands with dysplastic lining were often surrounded, compressed, and deformed by the fibrotic tissue. The compression of the glandular outlets by the collagen-rich tissue or by proliferating dysplastic cells appeared to be the two main factors in the histogenesis of these cysts. This may result in difficulty in differentiating, in biopsy specimens, between normal and dysplastic esophageal glands "trapped" in the collagen-rich fibrotic tissue and true invasive adenocarcinoma in the Barrett's mucosa.  相似文献   
9.
Granulomatous mastitis: a report of seven cases   总被引:5,自引:2,他引:5       下载免费PDF全文
The clinical history and histological features of seven cases of granulomatous mastitis are presented. The lesion occurs in young parous women as a tender extra-areolar breast lump. Histologically, non-caseating discrete granulomas are present, confined to breast lobules with, in three cases, coalescence of the granulomas and microabscess formation. Pathogenesis of the changes is discussed. It is thought that granulomatous mastitis is an entity morphologically distinct from duct ectasia/plasma cell mastitis and the commoner forms of granulomatous breast diseases.  相似文献   
10.
Discrete cardiovascular fitness groups consisting of high-fit (n=10) and low-fit (n=9) men performed a well-learned vigilance task and their self-report, performance, and plasma catecholamine responses were compared. No significant differences were observed between the fitness groups on self-report or psychomotor performance responses to the vigilance task. However, the low-fit group took significantly longer than high-fit subjects to complete the first of three sets of anagrams administered immediately after the vigilance task. Plasma norepinephrine but not epinephrine response was greater in the low-fit group compared to their high-fit counterparts. The findings indicate that enhanced cardiovascular fitness may be characterized by an attenuated plasma norepinephrine response to a vigilance task with sustained cognitive performance subsequent to the task.  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