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   298550篇
  免费   40197篇
  国内免费   3052篇
耳鼻咽喉   6371篇
儿科学   9087篇
妇产科学   5081篇
基础医学   23504篇
口腔科学   4869篇
临床医学   40638篇
内科学   78372篇
皮肤病学   10176篇
神经病学   28997篇
特种医学   12249篇
外国民族医学   6篇
外科学   62675篇
综合类   2127篇
现状与发展   74篇
一般理论   141篇
预防医学   17827篇
眼科学   6439篇
药学   11352篇
  2篇
中国医学   257篇
肿瘤学   21555篇
  2024年   761篇
  2023年   5432篇
  2022年   2358篇
  2021年   5754篇
  2020年   7780篇
  2019年   4879篇
  2018年   10521篇
  2017年   9713篇
  2016年   11156篇
  2015年   11596篇
  2014年   20024篇
  2013年   21876篇
  2012年   15692篇
  2011年   16335篇
  2010年   16334篇
  2009年   19759篇
  2008年   15702篇
  2007年   14688篇
  2006年   16564篇
  2005年   14159篇
  2004年   12867篇
  2003年   11360篇
  2002年   10891篇
  2001年   5159篇
  2000年   4083篇
  1999年   4715篇
  1998年   5652篇
  1997年   4985篇
  1996年   4681篇
  1995年   4386篇
  1994年   3026篇
  1993年   2630篇
  1992年   2135篇
  1991年   2170篇
  1990年   1658篇
  1989年   1768篇
  1988年   1569篇
  1987年   1414篇
  1986年   1370篇
  1985年   1246篇
  1984年   1178篇
  1983年   1081篇
  1982年   1257篇
  1981年   1099篇
  1980年   949篇
  1979年   677篇
  1978年   698篇
  1977年   799篇
  1976年   570篇
  1975年   568篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
83.
Four Chinese patients (2 boys, 2 girls), ages 4–9 years, who had episodes of perception error of body schema and objects are reported. The metamorphopsia, which had been named Alice in Wonderland syndrome, is the major presentation. All of them were proved to have acute Epstein-Barr virus infection, as documented by positive heterophil antibody test and/or positive IgM antibody to Epstein-Barr virus capsid antigen. The duration of the perception disorder ranged from 1 week to 3 months. We believe that any young child presenting with Alice in Wonderland syndrome should undergo examination for Epstein-Barr virus infection; complete recovery from the disorder can be expected.  相似文献   
84.
85.
86.
87.
PURPOSE: Epidermal growth factor receptor is expressed in pediatric malignant solid tumors. We conducted a phase I trial of gefitinib, an epidermal growth factor receptor tyrosine kinase inhibitor, in children with refractory solid tumors. PATIENTS AND METHODS: Gefitinib (150, 300, 400, or 500 mg/m2) was administered orally to cohorts of three to six patients once daily continuously until disease progression or significant toxicity. Pharmacokinetic studies were performed during course one (day 1 through 28). RESULTS: Of the 25 enrolled patients, 19 (median age, 15 years) were fully evaluable for toxicity and received 54 courses. Dose-limiting toxicity was rash in two patients treated with 500 mg/m2 and elevated ALT and AST in one patient treated with 400 mg/m2. The maximum-tolerated dose was 400 mg/m2/d. The most frequent non-dose-limiting toxicities were grade 1 or 2 dry skin, anemia, diarrhea, nausea, and vomiting. One patient with Ewing's sarcoma had a partial response. Disease stabilized for 8 to > or = 60 weeks in two patients with Wilms' tumor and two with brainstem glioma (one exophytic). At 400 mg/m2, the median peak gefitinib plasma concentration was 2.2 microg/mL (range, 1.2 to 3.6 microg/mL) and occurred at a median of 2.3 hours (range, 2.0 to 8.3 hours) after drug administration. The median apparent clearance and median half-life were 14.8 L/h/m2 (range, 3.8 to 24.8 L/h/m2) and 11.7 hours (range, 5.6 to 22.8 hours), respectively. Gefitinib systemic exposures were comparable with those associated with antitumor activity in adults. CONCLUSION: Oral gefitinib is well tolerated in children. Development of the drug in combination with cytotoxic chemotherapy will be pursued.  相似文献   
88.
The red eye     
A red eye is a cardinal sign of ocular inflammation. Most cases are benign and can be managed by the primary care provider. The key is recognizing cases requiring ophthalmological consultation by differentiating between ciliary and conjunctival injection. Ciliary injection indicates inflammation of the cornea, iris, or ciliary body, whereas conjunctival injection mainly affects the posterior conjunctival blood vessels. The author has stated that he does not have a significant financial interest or other relationship with any product manufacturer or provider of services discussed in this article. The author also does not discuss the use of off-label products, which includes unlabeled, unapproved, or investigative products or devices.  相似文献   
89.
90.
BACKGROUND: The dopamine transporter (DAT) is known to be a key regulator of dopamine, and recent studies of genetics, treatment, and imaging have highlighted the role of DAT in attention-deficit/hyperactivity disorder (ADHD). The findings of in vivo neuroimaging of DAT in ADHD have been somewhat discrepant, however. METHOD: Dopamine transporter binding was measured using a highly selective ligand (C-11 altropane) and positron emission tomography (PET). The sample consisted of 47 well-characterized, treatment-na?ve, nonsmoking, non-comorbid adults with and without ADHD. Additionally, control subjects had few symptoms of ADHD. RESULTS: Results showed significantly increased DAT binding in the right caudate in adults with ADHD compared with matched control subjects without this disorder. CONCLUSIONS: These results confirm abnormal DAT binding in the striatum of adults with ADHD and provide further support that dysregulation of DAT may be an important component of the pathophysiology of ADHD.  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