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   3320536篇
  免费   253302篇
  国内免费   8581篇
耳鼻咽喉   44760篇
儿科学   107203篇
妇产科学   89226篇
基础医学   476987篇
口腔科学   92143篇
临床医学   303378篇
内科学   651231篇
皮肤病学   75697篇
神经病学   268578篇
特种医学   128458篇
外国民族医学   749篇
外科学   504168篇
综合类   72019篇
现状与发展   16篇
一般理论   1286篇
预防医学   265148篇
眼科学   75831篇
药学   243237篇
  13篇
中国医学   6161篇
肿瘤学   176130篇
  2019年   27005篇
  2018年   37473篇
  2017年   28626篇
  2016年   32898篇
  2015年   37047篇
  2014年   52179篇
  2013年   78415篇
  2012年   104513篇
  2011年   111803篇
  2010年   67469篇
  2009年   64351篇
  2008年   104690篇
  2007年   111579篇
  2006年   112710篇
  2005年   109680篇
  2004年   104621篇
  2003年   101155篇
  2002年   97370篇
  2001年   147567篇
  2000年   151103篇
  1999年   127930篇
  1998年   39571篇
  1997年   34737篇
  1996年   35306篇
  1995年   34208篇
  1994年   31550篇
  1993年   29777篇
  1992年   101606篇
  1991年   99142篇
  1990年   96345篇
  1989年   92507篇
  1988年   85391篇
  1987年   83862篇
  1986年   78934篇
  1985年   75949篇
  1984年   57403篇
  1983年   48804篇
  1982年   29916篇
  1981年   26996篇
  1979年   52520篇
  1978年   37863篇
  1977年   31665篇
  1976年   29989篇
  1975年   31899篇
  1974年   37972篇
  1973年   36121篇
  1972年   33958篇
  1971年   31805篇
  1970年   29167篇
  1969年   27738篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
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   
102.
103.
104.
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   
105.
106.
Dosage form is a mean used for the delivery of drug to a living body. In order to get the desired effect the drug should be delivered to its site of action at such rate and concentration to achieve the maximum therapeutic effect and minimum adverse effect. Since oral route is still widely accepted route but having a common drawback of difficulty in swallowing of tablets and capsules. Therefore a lot of research has been done on novel drug delivery systems. This review is about oral dispersible tablets a novel approach in drug delivery systems that are now a day''s more focused in formulation world, and laid a new path that, helped the patients to build their compliance level with the therapy, also reduced the cost and ease the administration especially in case of pediatrics and geriatrics. Quick absorption, rapid onset of action and reduction in drug loss properties are the basic advantages of this dosage form.  相似文献   
107.
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   
108.
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   
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