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   2433990篇
  免费   188228篇
  国内免费   8402篇
耳鼻咽喉   33889篇
儿科学   76119篇
妇产科学   68788篇
基础医学   337129篇
口腔科学   70385篇
临床医学   214120篇
内科学   486920篇
皮肤病学   57041篇
神经病学   197701篇
特种医学   98680篇
外国民族医学   628篇
外科学   380501篇
综合类   57467篇
现状与发展   8篇
一般理论   812篇
预防医学   182836篇
眼科学   55026篇
药学   177312篇
  9篇
中国医学   4759篇
肿瘤学   130490篇
  2018年   22938篇
  2016年   21223篇
  2015年   23823篇
  2014年   33328篇
  2013年   50384篇
  2012年   63519篇
  2011年   67846篇
  2010年   41565篇
  2009年   40452篇
  2008年   64301篇
  2007年   69447篇
  2006年   70861篇
  2005年   68517篇
  2004年   66028篇
  2003年   64256篇
  2002年   61980篇
  2001年   115346篇
  2000年   118984篇
  1999年   100094篇
  1998年   28667篇
  1997年   25845篇
  1996年   26183篇
  1995年   25713篇
  1994年   23969篇
  1993年   22440篇
  1992年   80678篇
  1991年   78327篇
  1990年   76026篇
  1989年   73414篇
  1988年   68219篇
  1987年   67199篇
  1986年   63795篇
  1985年   61059篇
  1984年   46316篇
  1983年   39065篇
  1982年   23981篇
  1981年   21763篇
  1980年   20415篇
  1979年   42988篇
  1978年   31011篇
  1977年   26573篇
  1976年   24188篇
  1975年   26325篇
  1974年   31217篇
  1973年   30100篇
  1972年   28374篇
  1971年   26467篇
  1970年   24638篇
  1969年   23443篇
  1968年   21939篇
排序方式: 共有10000条查询结果,搜索用时 18 毫秒
51.
52.
53.
54.
Henna, derived from a combination of natural leaves and coloring additives, is a common decorative dye traditionally used in many Islamic religious celebrations. Para‐phenylenediamine (PPD), a major component of black henna tattoo, is a strong sensitizer and common allergen. We report a case of severe connubial allergic contact dermatitis after black henna heterotransfer in a girl.  相似文献   
55.
56.
Owing to the frequent incidence of blast-induced traumatic brain injury (bTBI) in recent military conflicts, there is an urgent need to develop effective therapies for bTBI-related pathologies. Blood-brain barrier (BBB) breakdown has been reported to occur after primary blast exposure, making restoration of BBB function and integrity a promising therapeutic target. We tested the hypothesis that treatment with dexamethasone (DEX) after primary blast injury potentiates recovery of an in vitro BBB model consisting of mouse brain endothelial cells (bEnd.3). DEX treatment resulted in complete recovery of transendothelial electrical resistance and hydraulic conductivity 1 day after injury, compared with 3 days for vehicle-treated injured cultures. Administration of RU486 (mifepristone) inhibited effects of DEX, confirming that barrier restoration was mediated by glucocorticoid receptor signaling. Potentiated recovery with DEX treatment was accompanied by stronger zonula occludens (ZO)-1 tight junction immunostaining and expression, suggesting that increased ZO-1 expression was a structural correlate to BBB recovery after blast. Interestingly, augmented ZO-1 protein expression was associated with specific upregulation of the α+ isoform but not the α isoform. This is the first study to provide a mechanistic basis for potentiated functional recovery of an in vitro BBB model because of glucocorticoid treatment after primary blast injury.  相似文献   
57.
58.
We report on a child with several café au lait spots in association with a lumbar lipomeningomyelocele as an apparently new association. Cutaneous markers, the identification of which plays a crucial role in the early diagnosis and management of spinal malformations, can accompany occult spinal dysraphism. Herein we report a case of lumbar lipomeningomyelocele associated with an overlying café au lait spot that served as a marker of occult spinal dysraphism. The patient also had segmental café au lait spots on the face, making the association unique.  相似文献   
59.
60.
Pediatric trachyonychia is an acquired nail disease that can cause distress to families. It is a poorly understood disease, and long‐term follow‐up data are lacking. We present an institutional review of 11 children with isolated pediatric trachyonychia followed over time. Children with the diagnosis of pediatric trachyonychia were identified and invited to participate. Pictures were taken on follow‐up and a questionnaire was answered. Exclusion criteria include having another diagnosis at the initial visit that causes nail dystrophy. Eleven patients with the diagnosis of pediatric trachyonychia were available for follow‐up. The mean age of appearance was 2.7 years (range 2–7 yrs) and the average follow‐up was 66 months (range 10–126 mos). Nine patients were treated with potent topical corticosteroids, one used only petrolatum, and one took vitamin supplements. One patient was found to have an additional skin and hair diagnosis of alopecia areata on follow‐up. On follow‐up, 82% noted improvement of the nails, whereas 18% noted no change. A majority of cases of pediatric trachyonychia are isolated and improve with time, regardless of treatment.  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