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   1371462篇
  免费   103827篇
  国内免费   4441篇
耳鼻咽喉   17101篇
儿科学   44281篇
妇产科学   36973篇
基础医学   202634篇
口腔科学   36877篇
临床医学   132068篇
内科学   267456篇
皮肤病学   26958篇
神经病学   114579篇
特种医学   49517篇
外国民族医学   366篇
外科学   191192篇
综合类   28945篇
现状与发展   1篇
一般理论   460篇
预防医学   115596篇
眼科学   29426篇
药学   101626篇
  6篇
中国医学   3292篇
肿瘤学   80376篇
  2021年   11560篇
  2019年   12154篇
  2018年   16975篇
  2017年   12802篇
  2016年   13837篇
  2015年   15860篇
  2014年   21667篇
  2013年   33062篇
  2012年   45844篇
  2011年   48592篇
  2010年   28042篇
  2009年   25704篇
  2008年   44239篇
  2007年   46679篇
  2006年   46775篇
  2005年   45252篇
  2004年   43258篇
  2003年   41116篇
  2002年   39932篇
  2001年   62452篇
  2000年   64083篇
  1999年   53781篇
  1998年   15102篇
  1997年   13702篇
  1996年   13494篇
  1995年   12789篇
  1994年   11950篇
  1993年   11208篇
  1992年   42540篇
  1991年   41676篇
  1990年   40243篇
  1989年   38230篇
  1988年   35346篇
  1987年   34385篇
  1986年   32877篇
  1985年   31306篇
  1984年   23459篇
  1983年   19957篇
  1982年   11938篇
  1979年   21106篇
  1978年   15047篇
  1977年   12271篇
  1976年   12022篇
  1975年   12310篇
  1974年   14981篇
  1973年   14645篇
  1972年   13511篇
  1971年   12591篇
  1970年   11636篇
  1969年   10573篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
102.
103.
104.
Purpose: Small pulmonary lesions that include ground-glass attenuation have been increasingly discovered because of progressive imaging diagnostic technologies. Despite the detection of such small lesions, sometimes it is quite difficult to localize them because of their size or considerable depth from the visceral pleura. In the present study, we examined the usefulness of computed tomography-guided lipiodol marking for thoracoscopic resection of impalpable pulmonary nodules.Methods: Fifty-six patients with an undiagnosed peripheral lesion(s) of the lung who had undergone preoperative computed tomography-guided lipiodol marking followed by video-assisted thoracoscopic surgery were studied.Results: All of the nodules were successfully marked by computed tomography-guided lipiodol marking, and all except for one case were localized by means of intraoperative fluoroscopy as clear spots. With regard to complications, pneumothorax occurred in 21 patients (37.5%), and only one patient required transient drainage. Although hemorrhaging in the lung parenchyma and hemosputum occurred in nine patients (16.1%) and one patient (1.8%), respectively, no patients were in serious condition. No intra- or postoperative mortality or morbidity was observed.Conclusion: Preoperative computed tomography-guided lipiodol marking of small or impalpable pulmonary nodules is a safe and useful procedure for thoracoscopic resection of the lung.  相似文献   
105.
106.
There are an estimated 56 million orphans and vulnerable children across sub-Saharan Africa. Communities typically care for orphan children through informal caring arrangements – either within or outside of kinship networks. Within Kenya, an estimated 250,000 children live on the streets. There is less research related to fostering attitudes of this special population than orphans and vulnerable children generally. Important research over the past decade has illuminated multiple ways in which children are made more vulnerable because of HIV, including parental death and street-migration from HIV-affected households. As HIV transitions from a terminal illness to a chronic, manageable one, research is also required to establish how parents living with HIV can be an asset to children. In this study, we assess whether mothers living with HIV were very willing to foster biologically-related children, and street-involved children, how these fostering attitudes differed from mothers not living with HIV, and whether differences in fostering attitudes by reported HIV status were mediated by social support, family functioning and general self-rated health. Approximately 40% of mothers living with HIV were very willing to provide long-term foster care to biologically-related or street-involved children. This was less than the percentage of mothers not living with HIV, who were very willing to foster biologically-related children (61%) or street-involved children (58%). Significant portions of these differences were explained by social support, family functioning and general self-rated health. Multi-sectoral approaches are suggested by these findings in order to improve the child-fostering capacity of mothers living with HIV. Improving social support, family functioning and general self-rated health among HIV-infected mothers may not only provide protective benefits for the mothers and their children, but also expand the community’s capacity to care for orphan and vulnerable children.  相似文献   
107.
108.
109.
110.
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