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   10511篇
  免费   934篇
  国内免费   44篇
耳鼻咽喉   9篇
儿科学   381篇
妇产科学   11篇
基础医学   1281篇
口腔科学   17篇
临床医学   282篇
内科学   201篇
皮肤病学   7716篇
神经病学   24篇
特种医学   45篇
外科学   142篇
综合类   380篇
预防医学   270篇
眼科学   24篇
药学   421篇
  1篇
中国医学   198篇
肿瘤学   86篇
  2024年   34篇
  2023年   235篇
  2022年   165篇
  2021年   403篇
  2020年   395篇
  2019年   357篇
  2018年   380篇
  2017年   366篇
  2016年   304篇
  2015年   312篇
  2014年   423篇
  2013年   451篇
  2012年   355篇
  2011年   383篇
  2010年   345篇
  2009年   356篇
  2008年   396篇
  2007年   378篇
  2006年   350篇
  2005年   357篇
  2004年   313篇
  2003年   288篇
  2002年   254篇
  2001年   317篇
  2000年   160篇
  1999年   243篇
  1998年   275篇
  1997年   228篇
  1996年   270篇
  1995年   241篇
  1994年   226篇
  1993年   191篇
  1992年   197篇
  1991年   185篇
  1990年   157篇
  1989年   171篇
  1988年   174篇
  1987年   133篇
  1986年   131篇
  1985年   121篇
  1984年   92篇
  1983年   95篇
  1982年   63篇
  1981年   31篇
  1980年   42篇
  1979年   33篇
  1978年   29篇
  1977年   28篇
  1976年   23篇
  1975年   27篇
排序方式: 共有10000条查询结果,搜索用时 91 毫秒
71.
T cells are known to develop a critical role in the pathogenesis of atopic dermatitis (AD) and bronchial asthma. T cells involved in AD express the skin homing receptor CLA, but no lung homing receptor has been identified in bronchial asthma. We compared different cell markers and the cytokine production in T cells from children with AD or bronchial asthma. We studied the involvement of CLA+ and CLA- T-cell subpopulations in these diseases. We studied 20 children with acute AD lesions, 15 with mild persistent asthma, and 15 non-atopic controls. All patients were sensitized to house dust mite (DP) and evaluated during the acute phase. Total and specific IgE were measured by immunoassay and the expression of different cell markers and the cytokine production was analyzed by flow cytometry in peripheral blood mononuclear cells. Total IgE was significantly higher in AD children and IgE to DP in the asthmatic children. There was a significant increase in CD25+ CD4+ cells in asthmatic children and in HLA-DR+ CD4+ and HLA-DR+ CD8+ cells in AD. In the CD4+ subsets, there was an increase in IL-13, IL-5 and TNF-alpha in AD compared to controls, a decrease in IFN-gamma in asthmatic children compared to controls, and an increase in IL-13, IL5, IL2, TNF-alpha, and IFN-gamma in the AD compared to asthmatic children. Changes in cytokine production were mainly detected in CLA+ cells in AD and in CLA- cells in asthma. Differences exist in total and specific IgE, activation markers, and cytokine patterns between AD children and children with asthma, with the former expressing a Th2 pattern whereas in asthmatic children we only detected a decrease in IFN-gamma. Moreover, the subpopulations (CLA+ vs. CLA-) expressing these changes were different, indicating that the underlying mechanisms in the two diseases are not exactly the same.  相似文献   
72.
BACKGROUND: Seborrhoeic dermatitis (SD) is a common dermatosis in human immunodeficiency virus (HIV)-positive patients, many of whom do not respond satisfactorily to conventional topical treatments such as corticosteroids and antifungals. OBJECTIVE: A pilot study to investigate the efficacy and tolerability of pimecrolimus cream 1% in HIV-positive patients with facial SD. METHODS: In a single-centre study, 21 HIV-infected patients with mild to severe SD were treated twice daily with pimecrolimus cream 1% for 14 days. Thereafter, treatment was discontinued and patients followed up for 5 weeks. Skin involvement at baseline and on days 7, 14, 21, 35 and 49 was assessed using a four-point clinical score and digital photography. MAIN OUTCOME MEASURES: Efficacy and safety of pimecrolimus cream 1% treatment and incidence of relapse in the follow-up phase. Results Marked improvement was seen in clinical parameters at day 7, with >or= 90% patients clear of symptoms at day 14. Relapse was observed at day 35 but signs were milder than at baseline. All patients responded to therapy, despite their immunological status. Pimecrolimus did not alter CD4(+) and CD8(+) T-cell counts or viral load during the treatment period. CONCLUSION: Pimecrolimus cream represents a new, effective therapeutic option for facial SD in HIV patients.  相似文献   
73.
目的:观察火把花根片治疗激素依赖性皮炎的疗效和安全性。方法:患者81例,分为治疗组和对照组。对照组:口服氯雷他定片,10mg/次,1次/天,同时外用氧化锌软膏;治疗组:在对照组用药的基础上加服火把花根片,5片/次,3次/天;疗程均为2个月。结果:治疗组总有效率达68.29%,对照组总有效率达24.24%,两组疗效比较有显著性差异(P〈0.01)。结论:火把花根片治疗面部激素依赖性皮炎安全、有效。  相似文献   
74.
BACKGROUND: The prevalence of atopic dermatitis (AD) in children has significantly increased worldwide in the past decades. Although it is well known that the number of AD patients has also been growing in Hungary, there are only a few published prevalence studies that allow international comparisons. OBJECTIVES: The aim of this study was to estimate the prevalence of AD among schoolchildren in Baranya County in 2005 and to compare the data with those from 2002. METHODS: The data from the 1454 children (771 girls, 683 boys) surveyed in 2002, and 1454 children (760 girls, 694 boys) surveyed in 2005, respectively, aged 7-14 years were analysed. The distinct populations of the 7- to 9-year-old age groups were separately compared in relation to their lifetime AD prevalence. RESULTS: The prevalence of AD accounted for 15.1% in 2002, and 16.1% in 2005. In the compared distinct 7- to 9-year-old populations the prevalence rates were 17.0% in 2002 and 17.1% in 2005. There were no statistically significant differences between the data of the two surveys. CONCLUSIONS: The results indicate the high prevalence rate of AD nearly approaching the markedly high values registered in the welfare countries, and could indicate that AD has reached a plateau in Hungary.  相似文献   
75.
76.
BACKGROUND: Olopatadine hydrochloride (olopatadine; Allelock) is one of the second-generation antihistamines that are treated for allergic disorders such as rhinitis, urticaria and eczema dermatitis. Olopatadine has recently been shown to have inhibitory effects on the chronic contact hypersensitivity induced by repeated application of oxazolone in mice. Although topical steroids have widely been prescribed for atopic dermatitis, a relapse often occurs within several days after discontinuation of their prolonged use. OBJECTIVES: We investigated the possible efficacy of olopatadine against the relapse after discontinuation of prolonged use of topical prednisolone in the Balb/c mice with oxazolone-induced chronic contact hypersensitivity. METHODS: Mice with the chronic contact hypersensitivity induced by repeated application of oxazolone were treated with olopatadine as a sequential therapeutic agent. The effects of olopatadine were quantified by measurements of ear-swelling, and levels of cytokines and histamine in the lesioned ear. Results Topical prednisolone (0.05 mg/ear/day) significantly inhibited the increases in ear swelling and production of IL-1beta, IL-4, IL-18, granulocyte-macrophage colony-stimulating factor (GM-CSF) and histamine. However, after discontinuation of the treatment with topical prednisolone, the inflammation relapsed and the IL-4 level exceeded the control one. The sequential treatment with olopatadine (10 mg/kg/day) after discontinuation of the treatment with topical prednisolone alone, or topical prednisolone with olopatadine, significantly inhibited the increases in ear swelling and levels of IL-1beta, IL-4, IL-18, GM-CSF, nerve growth factor and histamine. CONCLUSIONS: These results indicate that olopatadine is an antihistamine agent having inhibitory activities against the rebound phenomenon following the discontinuation of topical steroid therapy. Olopatadine is thus expected to be a sequential therapeutic agent after discontinuation of the chronic treatment with a topical steroid.  相似文献   
77.
We report a case of rare multiple internal resorptions. Etiology of multiple internal resorptions is unknown. Interestingly, the patient had an atopic dermatitis, which is possibly related to multiple and rapid internal resorptions.  相似文献   
78.
Atopic dermatitis (AD) is today the most common, chronic inflammatory skin disease among children in developed countries. Its cumulative prevalence varies from 20% in northern Europe and the USA to approximately 5% in Mediterranean countries. As a chronic disease it puts a special demand on treatment. There is no curative therapy, but competent guidance on treatment principles can control the disease in most, if not all children. This article summarizes the evidence-based knowledge that relates to the treatment of atopic eczema. It also gives advice and opinions on prophylactic measures as these are the focus of interest from most parents. LEARNING OBJECTIVE: This article should enable you to give advice and guidance to parents of children with AD, including what is necessary for diagnosis, what is of value and importance considering allergies and allergological investigations, allergen exposure, prophylactic measures, diets and indoor environment. Finally, you should be able to explain the diversity of treatment principles for parents.  相似文献   
79.
A carpet factory worker, exposed to a number of different dyes, developed a severe hand dermatitis. The handling of warm, wet and freshly-dyed yarn with unprotected hands was thought to have caused the onset of dermatitis. Patch testing indicated that the patient was sensitive to only one of the dyes handled, namely Synacril Red 3B liquid, which is based on the single dyestuff Basic Red 22 (CI 11055). Chemical analysis revealed the dyestuff to be of high purity (greater than 95%), suggesting that sensitization was caused by the Basic Red 22 dyestuff itself and not by an avoidable impurity.  相似文献   
80.
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