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   1343441篇
  免费   115069篇
  国内免费   6380篇
耳鼻咽喉   16818篇
儿科学   43248篇
妇产科学   36788篇
基础医学   184389篇
口腔科学   36405篇
临床医学   121345篇
内科学   280192篇
皮肤病学   31958篇
神经病学   111239篇
特种医学   55830篇
外国民族医学   274篇
外科学   211153篇
综合类   31603篇
现状与发展   2篇
一般理论   420篇
预防医学   107408篇
眼科学   28222篇
药学   94192篇
  5篇
中国医学   2229篇
肿瘤学   71170篇
  2018年   13530篇
  2017年   10764篇
  2016年   12913篇
  2015年   14433篇
  2014年   20170篇
  2013年   30048篇
  2012年   36773篇
  2011年   39464篇
  2010年   24683篇
  2009年   24222篇
  2008年   36847篇
  2007年   39362篇
  2006年   40430篇
  2005年   38989篇
  2004年   37212篇
  2003年   36266篇
  2002年   34230篇
  2001年   66125篇
  2000年   67963篇
  1999年   56650篇
  1998年   16818篇
  1997年   15079篇
  1996年   16061篇
  1995年   16291篇
  1994年   15133篇
  1993年   14192篇
  1992年   47130篇
  1991年   45768篇
  1990年   44000篇
  1989年   41860篇
  1988年   38782篇
  1987年   38097篇
  1986年   35877篇
  1985年   34649篇
  1984年   26384篇
  1983年   22125篇
  1982年   13866篇
  1981年   12465篇
  1980年   11731篇
  1979年   23550篇
  1978年   17085篇
  1977年   14394篇
  1976年   13187篇
  1975年   13727篇
  1974年   16099篇
  1973年   15400篇
  1972年   14176篇
  1971年   13042篇
  1970年   11881篇
  1969年   11103篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
32.
33.
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   
34.
35.
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   
36.
37.
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   
38.
39.
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   
40.
Sinus venosus atrial septal defect (SV‐ASD) usually coexists with partial anomalous pulmonary vein connection (PAPVC). It is a difficult diagnosis in transthoracic echocardiography (TTE) due to eccentric position of defects. We present a rare case of atypical anatomical variation in PAPVC, which was never described before. Two right pulmonary veins drained into superior vena cava, which overrode SV‐ASD and interatrial septum, a third pulmonary vein into the right atrium. Complete diagnosis could not be set after TTE, nor transesophageal echocardiography, whereas angio‐CT was finally conclusive. This diagnostic approach allowed the surgical planning.  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