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   1304篇
  免费   72篇
  国内免费   68篇
儿科学   49篇
妇产科学   8篇
基础医学   99篇
口腔科学   15篇
临床医学   173篇
内科学   297篇
皮肤病学   21篇
神经病学   29篇
特种医学   257篇
外科学   125篇
综合类   46篇
预防医学   129篇
眼科学   15篇
药学   55篇
中国医学   2篇
肿瘤学   124篇
  2021年   17篇
  2020年   9篇
  2019年   9篇
  2018年   20篇
  2017年   8篇
  2016年   9篇
  2015年   19篇
  2014年   32篇
  2013年   37篇
  2012年   29篇
  2011年   32篇
  2010年   35篇
  2009年   40篇
  2008年   27篇
  2007年   60篇
  2006年   25篇
  2005年   32篇
  2004年   29篇
  2003年   31篇
  2002年   40篇
  2001年   23篇
  2000年   33篇
  1999年   26篇
  1998年   61篇
  1997年   40篇
  1996年   60篇
  1995年   54篇
  1994年   43篇
  1993年   53篇
  1992年   19篇
  1991年   17篇
  1990年   28篇
  1989年   35篇
  1988年   41篇
  1987年   47篇
  1986年   35篇
  1985年   39篇
  1984年   26篇
  1983年   17篇
  1982年   19篇
  1981年   25篇
  1980年   23篇
  1979年   12篇
  1978年   22篇
  1977年   21篇
  1976年   9篇
  1975年   13篇
  1974年   6篇
  1972年   6篇
  1971年   8篇
排序方式: 共有1444条查询结果,搜索用时 31 毫秒
1.
2.
3.
4.
5.
6.
The study examined predictors of children's prosocial responses to adult negative emotions. An adult displayed anger, sadness and pain during play sessions with 39 preschoolers (mean age = 43 months). Older children responded more prosocially to all three emotions, whereas children with greater emotion knowledge responded more prosocially to the adult's sadness. Children who behaved prosocially in response to peers' negative emotions also were prosocial after the adult's negative emotions, even with effects of age and emotion knowledge held constant. Assertive children responded more prosocially to the adult's anger, even with effects of other variables held constant. Both theoretical and practical implications are discussed.  相似文献   
7.
Inversion recovery (IR), commonly considered a pulse sequence capable of producing T1-weighted images with excellent display of normal anatomy, is versatile: The null point and peak time provide a useful, succinct summary of the properties of IR and its capacity for producing both T1- and T2-weighted images. Shortening of the inversion time (TI) and creation of a short-TI inversion-recovery (STIR) pulse sequence increases sensitivity to malignancy and other abnormalities by making the effects of prolonged T1 and T2 on signal intensity additive and by nulling the signal from fat. The authors examined over 300 patients with various malignancies and compared STIR images with T1- and T2-weighted images obtained at 0.5 T. In 43 cases, signal-difference-to-noise ratios (SD/Ns) were calculated between tumor, fat, and muscle. In general, STIR images demonstrated tumor as a conspicuously high-intensity area in a background of muted, discernible anatomic detail. The good contrast achieved with STIR sequences between tumor and fat (SD/N = 18.1) and tumor and muscle (SD/N = 12.9) consolidated into a single image the information contained separately on T1- and T2-weighted images, which facilitates efficient detection and localization of malignancy.  相似文献   
8.
Goei  R; Baeten  C; Arends  JW 《Radiology》1988,168(2):303-306
Sixteen cases of histopathologically proved solitary rectal ulcer syndrome were encountered. Fifteen patients underwent barium enema study; in nine cases the findings--including rectal stricture, granularity of the mucosa, and thickened rectal folds-were nonspecific. In six cases the study was normal. All patients had a long history of defecation disorders, and defecography was performed in all. In seven cases, intussusception of the rectal wall was seen; in another case the intussusception was accompanied by a rectocele. One case showed rectal prolapse. In four cases, failed relaxation of the puborectalis occurred and prevented the passage of the bolus; in another case there was abnormal perineal descent. In two patients studies were normal. In patients with defecation disorders, the possibility of this syndrome should be considered. Defecography is the method of choice for establishing the diagnosis.  相似文献   
9.
10.
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