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   1739篇
  免费   180篇
  国内免费   78篇
耳鼻咽喉   1篇
儿科学   2篇
妇产科学   19篇
基础医学   69篇
口腔科学   63篇
临床医学   64篇
内科学   105篇
皮肤病学   67篇
神经病学   24篇
特种医学   22篇
外科学   51篇
综合类   281篇
现状与发展   1篇
预防医学   419篇
眼科学   17篇
药学   331篇
中国医学   281篇
肿瘤学   180篇
  2024年   1篇
  2023年   14篇
  2022年   22篇
  2021年   54篇
  2020年   41篇
  2019年   45篇
  2018年   45篇
  2017年   60篇
  2016年   66篇
  2015年   73篇
  2014年   116篇
  2013年   158篇
  2012年   86篇
  2011年   125篇
  2010年   99篇
  2009年   99篇
  2008年   118篇
  2007年   109篇
  2006年   76篇
  2005年   70篇
  2004年   72篇
  2003年   67篇
  2002年   50篇
  2001年   51篇
  2000年   53篇
  1999年   28篇
  1998年   42篇
  1997年   35篇
  1996年   23篇
  1995年   22篇
  1994年   13篇
  1993年   17篇
  1992年   17篇
  1991年   7篇
  1990年   7篇
  1989年   5篇
  1988年   4篇
  1987年   3篇
  1985年   2篇
  1983年   1篇
  1982年   1篇
排序方式: 共有1997条查询结果,搜索用时 31 毫秒
1.
Experimental autoimmune encephalomyelitis (EAE) is a mouse model for multiple sclerosis (MS), in which an inflammatory demyelination and axonal damage occurs. Kombucha tea is a fermented beverage made from kombucha mushroom, brewed tea, and sugar. In recent years kombucha tea has attracted interest due to its pharmacological properties like antioxidant effects. The aim of the present research was to test the therapeutic effect of kombucha tea in EAE. We induced EAE model in 18 female C57BL/6 mice by inoculation of myelin oligodendrocyte glycoprotein-35-55 (MOG35-55) in complete Freund’s adjuvant emulsion. Then, in order to ameliorate EAE symptoms, we used kombucha tea. During the course of study clinical evaluation was assessed, and on the day 21 post-immunization, for evaluation of nitric oxide (NO), total antioxidants capacity and tumor necrosis factor-alpha (TNF-α), blood samples were taken from the heart of mice. The mice were sacrificed and brains and cerebellums of mice were removed for histological analysis. Our findings demonstrated that kombucha tea had beneficial effects on EAE by lower incidence, attenuation in the severity, and also a delay in the onset of disease. Histological analysis showed that inflammatory criteria including the number of infiltrated immune cells and plaques as well as demyelination in kombucha tea dosed mice were significantly lower than the control group. Also, in comparison with control mice, the serum levels of NO and TNF-α in kombucha tea-treated mice were significantly decreased. Kombucha tea with its potential therapeutic effects and immunomodulatory properties might be proposed, after additional necessary tests and trials, for treatment of MS.  相似文献   
2.
3.
除山茶科植物来源的传统茶叶外,市场上还广泛流通着许多口感不错的药食同源的别样茶。传统茶和别样茶统称为茶饮。梳理了茶饮的发展历程,丰富其内涵及多样性,突出其"治未病"和慢病防治的功效,探明部分功能分子基础,明确其临床应用价值,展望其未来发展方向。茶饮作为"健康中国"的重要载体,具有大规模市场开发的广阔前景,可以更好地为人民群众健康服务,同时亟须提供更精准的科学依据。  相似文献   
4.
Obesity and being overweight are linked with a cluster of metabolic and vascular disorders that have been termed the metabolic syndrome. This syndrome promotes the incidence of cardiovascular diseases that are an important public health problem because they represent a major cause of death worldwide. Whereas there is not a universally-accepted set of diagnostic criteria, most expert groups agree that this syndrome is defined by an endothelial dysfunction, an impaired insulin sensitivity and hyperglycemia, dyslipidemia, abdominal obesity and hypertension. Epidemiological studies suggest that the beneficial cardiovascular health effects of diets rich in green tea are, in part, mediated by their flavonoid content, with particular benefits provided by members of this family such as epigallocatechin gallate (EGCG). Although their bioavailability is discussed, various studies suggest that EGCG modulates cellular and molecular mechanisms of various symptoms leading to metabolic syndrome. Therefore, according to in vitro and in vivo model data, this review attempts to increase our understanding about the beneficial properties of EGCG to prevent metabolic syndrome.  相似文献   
5.
目的:探讨帕金森病大鼠氧化应激反应及绿茶多酚的干预作用。方法:采用6-羟基多巴胺(6-OHDA)偏侧损毁纹状体制备帕金森病大鼠模型,并随机分为模型组、绿茶多酚组,另取正常对照组、假手术组大鼠,每组10只。分别在6周后进行神经行为学检测后,取纹状体,应用比色法分别测定各组大鼠纹状体内超氧化物歧化酶(SOD)、丙二醛(MDA)、谷胱甘肽(GSH)、谷胱甘肽过氧化物酶(GSH-Px)的含量。结果:帕金森病模型组大鼠纹状体内SOD、GSH、GSH-Px的含量均明显减少,MDA含量呈增加趋势;而绿茶多酚组大鼠纹状体内SOD、GSH、GSH-Px的含量均呈现增加趋势,MDA含量呈减少趋势。结论:绿茶多酚能较好地改善帕金森病大鼠的氧化应激反应,可能通过清除自由基,减轻对细胞的损伤,从而缓解帕金森病的症状。  相似文献   
6.
The present study aimed to determine the effect of a green tea supplement on anthropometric indices and inflammatory factors in women with polycystic ovary syndrome (PCOS). In this randomized clinical trial, 45 women with PCOS were randomly allocated into two groups receiving green tea tablets or placebo. The period of intervention was 45 days. The serum levels of interleukin 6, high‐sensitivity C‐reactive protein, and tumor necrosis factor α were measured before and after intervention period using the related kits. Anthropometric indices also were measured. The mean of body mass index, weight, waist circumference, and body fat percentage in the green tea group were reduced significantly. However, no significant difference was observed between the two groups. Also, there was no significant effect on the levels of inflammatory factors. The present results suggest that daily consumption of green tea tablets did not cause any effect on inflammation biomarkers in PCOS women. However, it may be effective as a complementary treatment for weight control in these women. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
7.
OBJECTIVE: To compare the antimicrobial activity of tea tree oil, garlic, and chlorhexidine solutions against oral microorganisms. METHOD: The five-week study consisted of thirty subjects. The first week was considered baseline. All subjects used a control solution (second week), and were randomly divided into the three groups (third week): G1-0.12% chlorhexidine; G2 - 2.5% garlic (Allium sativum, L.); and G3 - 0.2% tea tree oil (Melaleuca alternifolia). Dishes containing blood agar and Mitis Salivarius Bacitracin agar (MSB) were inoculated with the subjects' saliva (collected twice a week). Total microorganisms and mutans streptococci were counted in blood agar and MSB, respectively. RESULTS: Chlorhexidine and garlic groups showed antimicrobial activity against mutans streptococci, but not against other oral microorganisms. The tea tree oil group showed antimicrobial activity against mutans streptococci and other oral microorganisms. Maintenance of reduced levels of microorganisms was observed only for garlic and tea tree oil during the two consecutive weeks (fourth and fifth). Unpleasant taste (chlorhexidine 40%, tea tree oil 30%, garlic 100%), burning sensation (chlorhexidine 40%, tea tree oil 60%, garlic 100%), bad breath (chlorhexidine 40%, tea tree oil 20%, garlic 90%), and nausea (chlorhexidine 0%, tea tree oil 10%, garlic 30%) were reported. CONCLUSION: Garlic and tea tree oil might be an alternative to chlorhexidine.  相似文献   
8.
目的:观察咀嚼2种胶姆糖后口腔菌斑pH值的变化情况.方法:选择8例健康受试者(年龄23~27岁,男4例,女4例)参加3次试验,每次实验开始前停止刷牙24h,在使用10%的蔗糖溶液漱口前以及漱口后5、10、15、20min,用Beetrode pH微电极测量口腔菌斑的pH值,作为基线值.1周后先测量静息pH值,再用蔗糖溶液漱口,1min后给予无糖胶姆糖咀嚼,在5、10、15、20min时间点,分别测量非咀嚼侧的菌斑pH值.1周后重复上述实验,胶姆糖改为含茶多酚胶姆糖.应用SPSS10.0统计软件包对数据进行单因素方差分析和SNK分析.结果:与基线值比较,咀嚼2种胶姆糖都能有效防止由于含漱蔗糖水导致的菌斑pH值下降,并使pH值维持在静息pH值以上.2种胶姆糖之间无显著性差异(P>0.05).结论:咀嚼2种胶姆糖均能防止菌斑pH值下降,减少患龋危险.  相似文献   
9.
BACKGROUND: Extrinsic staining of teeth is considered to be unsightly and a number of 'whitening' toothpastes have been formulated to inhibit or remove such tooth discoloration. The aim of this study was to compare the stain prevention of two toothpastes. METHOD: The study was a single-blind, randomised, placebo-controlled, crossover design, balanced for residual effects involving 24 healthy dentate volunteers. The treatments were as follows: (1) a whitening toothpaste product, (2) an experimental toothpaste formulation and (3) water. For each 4-day rinse period, subjects were rendered stain free on the teeth and tongue. Approximately on the hour from 09:00 to 16:00 hours, subjects rinsed with chlorhexidine mouth rinse for 1 min followed by warm black tea for 1 min. The treatment interventions were at 09:00 and 16:00 hours and before the chlorhexidine rinse. The toothpastes were rinsed as 3 g/10 ml water slurries and water as a 10 ml rinse each for 2 min. On day 5, subjects were scored for tooth and tongue stain intensity and area, and the product of these was calculated. The washout period was at least 9 days. RESULTS: Treatment differences for the teeth were highly significant but not for the tongue. Paired contrasts for tooth stain intensity, area and product were mostly all significantly in favour of reduced staining by the experimental formulation compared with water and the whitening product. There were no significant differences between water and the whitening product. CONCLUSIONS: Using a forced dietary staining method, the data support a tooth stain-inhibitory/-removal action for the experimental formulation, but not the whitening product.  相似文献   
10.
目的:观察芪术养生保健袋泡茶对免疫低下小鼠免疫功能的影响。方法:取ICR小鼠60只,雄性,随机分为正常组、模型组、玉屏风组、袋泡茶高剂量组、袋泡茶中剂量组和袋泡茶低剂量组,每组各10只。正常组和模型组给予等量生理盐水,玉屏风组给予玉屏风口服液0.02m L·g-1,袋泡茶高剂量组给予袋泡茶14.4 g·kg-1,袋泡茶中剂量组给予袋泡茶7.2 g·kg-1,袋泡茶低剂量组给予袋泡茶3.6 g·kg-1。通过芪术养生保健袋泡茶对免疫低下小鼠血液中炭粒吞噬廓清能力、溶血素抗体生成及迟发型超敏(DTH)反应等的影响,观察其对免疫低下小鼠免疫功能的影响。结果:与正常组比较,模型组小鼠吞噬指数K值明显降低,差异具有统计学意义(P0.05);与模型组比较,玉屏风组小鼠吞噬系数较明显降低,芪术袋泡茶各剂量组有升高趋势,差异具有统计学意义(P0.05)。与正常组比较,芪术养生袋泡茶模型组小鼠OD值、绵羊红细胞半数溶血时吸收度值(HC50)明显降低,差异具有统计学意义(P0.05);与模型组比较,芪术养生袋泡茶各剂量组OD值、HC50明显升高,差异具有统计学意义(P0.05)。与正常组比较,模型组小鼠OD值明显降低,差异具有统计学意义(P0.05)。与模型组比较,袋泡茶各剂量组OD值明显升高,差异具有统计学意义(P0.05)。结论:芪术养生袋泡茶具有增强免疫低下小鼠血液中炭粒吞噬廓清能力,促进免疫低下小鼠溶血素抗体生成、对免疫低下小鼠的迟发型超敏反应具有增强作用。  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