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   1091790篇
  免费   68508篇
  国内免费   2827篇
耳鼻咽喉   15142篇
儿科学   36012篇
妇产科学   31949篇
基础医学   151975篇
口腔科学   30322篇
临床医学   90719篇
内科学   217874篇
皮肤病学   23506篇
神经病学   83839篇
特种医学   46461篇
外国民族医学   399篇
外科学   169831篇
综合类   20136篇
一般理论   275篇
预防医学   81453篇
眼科学   24159篇
药学   77273篇
  2篇
中国医学   1958篇
肿瘤学   59840篇
  2018年   13052篇
  2017年   11300篇
  2016年   11223篇
  2015年   13823篇
  2014年   17090篇
  2013年   23348篇
  2012年   36343篇
  2011年   33203篇
  2010年   19478篇
  2009年   20050篇
  2008年   29277篇
  2007年   31566篇
  2006年   31947篇
  2005年   39045篇
  2004年   39304篇
  2003年   34096篇
  2002年   29021篇
  2001年   44994篇
  2000年   44009篇
  1999年   41088篇
  1998年   10582篇
  1997年   9487篇
  1996年   9508篇
  1995年   8866篇
  1994年   8450篇
  1992年   33991篇
  1991年   33055篇
  1990年   32779篇
  1989年   31420篇
  1988年   29191篇
  1987年   28632篇
  1986年   27460篇
  1985年   25739篇
  1984年   18972篇
  1983年   16042篇
  1982年   8987篇
  1979年   18015篇
  1978年   12332篇
  1977年   10226篇
  1976年   9543篇
  1975年   11206篇
  1974年   13472篇
  1973年   12666篇
  1972年   12165篇
  1971年   11414篇
  1970年   10897篇
  1969年   10264篇
  1968年   9707篇
  1967年   9056篇
  1966年   8280篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
71.
72.
73.
74.
75.
76.
77.
Psoriasis is a chronic, inflammatory, immune‐mediated disease. Approximately 30% of patients have disease onset before age 18 years. Psoriasis in children and adolescents may be difficult to control, with subsequent poor quality of life and psychosocial consequences. We describe the case of a 12‐year‐old boy with severe, refractory, chronic plaque psoriasis for 6 years. Various therapeutic regimens including different topical corticosteroids, topical vitamin D analogs, phototherapy, photochemotherapy, systemic therapy with methotrexate, cyclosporin, and combination therapies showed only partial or transient responses with frequent relapses. Because anti‐interleukin‐12/23 agents have been successfully used in adults with psoriasis, ustekinumab was initiated and our patient showed a rapid, excellent, sustained response. No recurrence or flares have been observed after 33 months of follow‐up. This case illustrates that ustekinumab may be an effective and safe therapeutic option in adolescents with psoriasis.  相似文献   
78.
We report a case of intestinal obstruction in a 73-year-old woman caused by ileocolic intussusception. The underlying cause was a giant submucosal ulcerating lipoma (6?×?3.3?×?3.8 cm) extending from the superior mucosal lip of Bauhin’s valve. Abdominal ultrasonography showed a pathognomonic target-like mass appearing as multiple concentric rings. CT scan confirmed the diagnosis. Because of apparent obstruction, a laparotomy with right hemicolectomy and ileocolic anastomosis was performed. Lipomas most frequently occur in the cecum and ascending colon where they represent the most common submucosal mesenchymal tumor. They typically occur in elderly women with an incidence that varies from 0.15 to 0.56 %. Pain, rectal bleeding, and obstruction are typical symptoms. When faced with an intussusception in children, reduction with air per rectum can be performed. In adults, however, malignant cell spreading and seeding is of big concern. Since approximately 20–50 % of all underlying causes are malignant, explorative surgery is favored in adults.  相似文献   
79.
80.
Attachment is a behavioral and physiological system, which enables individual’s dynamic adaptation to its environment. Attachment develops in close interaction between an infant and his/her mother, plays an important role in the development of the infant’s brain, and influences the quality of interpersonal relationships throughout life.Security of attachment is believed to influence individual response to stress, exposing insecurely organized individuals to deregulated autonomic nervous system and exaggerated hypothalamic-pituitary-adrenal activity, which, in turn, produces increased and prolonged exposure to stress-hormones. Such stress responses may have considerable implications for the development of diverse health-risk conditions, such as insulin resistance and hyperlipidemia, shown by numerous studies.Although the mechanisms are not yet fully understood, there is compelling evidence highlighting the role of psychological stress in the development of type 1 diabetes (T1D). One of the possible contributing factors for the development of T1D may be the influence of attachment security on individual stress reactivity. Thus, the suggestion is that insecurely attached individuals are more prone to experience increased and prolonged influence of stress hormones and other mechanisms causing pancreatic beta-cell destruction.The present paper opens with a short overview of the field of attachment in children, the principal attachment classifications and their historic development, describes the influence of attachment security on individual stress-reactivity and the role of the latter in the development of T1D. Following is a review of recent literature on the attachment in patients with T1D with a conclusion of a proposed role of attachment organization in the etiology of T1D.  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