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   1403篇
  免费   107篇
  国内免费   2篇
耳鼻咽喉   26篇
儿科学   63篇
妇产科学   31篇
基础医学   197篇
口腔科学   27篇
临床医学   107篇
内科学   341篇
皮肤病学   14篇
神经病学   78篇
特种医学   84篇
外科学   99篇
综合类   24篇
预防医学   106篇
眼科学   78篇
药学   143篇
中国医学   5篇
肿瘤学   89篇
  2023年   12篇
  2022年   17篇
  2021年   66篇
  2020年   25篇
  2019年   48篇
  2018年   55篇
  2017年   36篇
  2016年   26篇
  2015年   46篇
  2014年   55篇
  2013年   76篇
  2012年   123篇
  2011年   93篇
  2010年   70篇
  2009年   51篇
  2008年   84篇
  2007年   80篇
  2006年   87篇
  2005年   70篇
  2004年   72篇
  2003年   79篇
  2002年   62篇
  2001年   16篇
  2000年   8篇
  1999年   12篇
  1998年   10篇
  1997年   3篇
  1996年   5篇
  1995年   4篇
  1992年   8篇
  1991年   8篇
  1990年   9篇
  1989年   3篇
  1988年   5篇
  1986年   4篇
  1979年   5篇
  1978年   4篇
  1975年   2篇
  1974年   3篇
  1973年   3篇
  1972年   6篇
  1971年   5篇
  1970年   7篇
  1968年   4篇
  1966年   7篇
  1965年   2篇
  1960年   3篇
  1958年   3篇
  1957年   2篇
  1956年   4篇
排序方式: 共有1512条查询结果,搜索用时 31 毫秒
1.
2.
Dermal and pulmonary tuberculous lesions were produced in rabbits with BCG, biopsied, incubated in vitro with tritiated thymidine (3HT) under hyperbaric oxygen, quickly frozen, sectioned in a cryostat, stained for the lysosomal enzyme β-galactosidase, autoradiographed, stained for acid-fast bacilli and counterstained with hematoxylin. As macrophages developed into epithelioid cells, they could still divide—ie, incorporate 3HT. However, once they became fully mature epithelioid cells that were 4-plus in β-galactosidase, they could not do so. Tuberclebacilli did not stimulate macrophage division. On the contrary, macrophages containing bacilli did not divide, except when the lesions began. During the development of tuberculous lesions, macrophages (including those rich in enzymes and those containing bacilli) died, forming caseous centers. Therefore, local cell division did not seem to be the main mechanism by which macrophages reduced their bacillary load. Such division seemed mainly to occur in young macrophages that had recently immigrated into the lesions from the bloodstream and had not yet ingested bacilli.  相似文献   
3.
4.
5.
Angiodysplasia of gastrointestinal tract is still thought to be an entity of unknown aetiology. This lesion is most commonly observed in elderly patients presenting with severe and persistent iron deficiency anaemia, following occult blood loss or acute episodes of haematemesis. In the stomach antral vascular ectasia is the most common presentation. We report an autopsy case of vascular ectasia in the cardia of stomach in a young patient with clinical symptoms of anaemia as the presentation and an associated secondary hemosiderosis of liver.  相似文献   
6.
7.
8.
9.
Seventeen children presenting with leucocoria were subjected to complete investigations. Careful A and B mode ultrasonography allowed us to make the correct diagnosis of retinoblastoma in 11 eyes of 9 patients, which was confirmed by histopathology or by response to radiotherapy. The diagnosis of retinoblastoma was not missed ultrasonographically in any of the eyes studied. The "V/W" configuration and absence of vascular pulsations on A mode; the "mixed" pattern and absence of choroidal excavation and orbital shadowing on B mode were found to be essential echographic features in characterizing the tumor and in differentiating it from other conditions including vitreous hemorrhage. The ultrasonographic features of early extraocular extension of retinoblastoma are discussed. Careful ultrasonic evaluation of leucocoria would seem to be invaluable in obviating the possibility of misdiagnosis in such problematic cases.  相似文献   
10.
There is a deficit of literature regarding the association between nickel allergy–induced symptoms and implanted devices. This report describes a case of nickel allergy causing debilitating migraine-like symptoms, failing to resolve with medical therapy, requiring surgical removal of the device and repair of the defect.  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