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101.
Chandrashekhar VM Halagali KS Nidavani RB Shalavadi MH Biradar BS Biswas D Muchchandi IS 《Journal of ethnopharmacology》2011,137(1):336-340
Ethnopharmacological relevance
Chamomile is most popular used medicinal plant and extensively consumed as a tea or tisanes. Traditionally this plant was used for treatment of many ailments such as allergy disorders and inflammatory mediated diseases.Aim of the study
We investigated the effects of anti-allergic activity of Matricaria recutita L. on mast cell mediated allergic models.Materials and methods
The protective effect of methanol extract of Matricaria recutita against compound 48/80 induced anaphylaxis and pruritis models for acute phase of hypersensitivity reactions were carried out. The late phase hypersensitivity reactions by compound 48/80 induced mast cell degranulation and histamine release from blood along with serum nitric oxide (NO), rat peritoneal fluid nitric oxide (NO) and bronchoalveolar fluid nitric oxide (NO) levels were measured.Results
The methanol extract of Matricaria recutita L. showed inhibitory effects on anaphylaxis induced by compound 48/80 and significant dose dependent anti-pruritis property was observed by inhibiting the mast cell degranulation. Mast cell membrane stabilization activity was also observed in compound 48/80 induced mast cell activation. Dose dependent reduction in the histamine release, along with decreased release of serum, rat peritoneal and BAL fluid nitric oxide (NO) levels were observed.Conclusion
These results suggest that the methanol extract of Matricaria recutita showed potent anti-allergic activity by inhibition of histamine release from mast cells. 相似文献102.
Green tea and bone metabolism 总被引:1,自引:0,他引:1
Osteoporosis is a major health problem in both elderly women and men. Epidemiological evidence has shown an association between tea consumption and the prevention of age-related bone loss in elderly women and men. Ingestion of green tea and green tea bioactive compounds may be beneficial in mitigating bone loss of this population and decreasing their risk of osteoporotic fractures. This review describes the effect of green tea or its bioactive components on bone health, with an emphasis on (i) the prevalence and etiology of osteoporosis; (ii) the role of oxidative stress and antioxidants in osteoporosis; (iii) green tea composition and bioavailability; (iv) the effects of green tea and its active components on osteogenesis, osteoblastogenesis, and osteoclastogenesis from human epidemiological, animal, as well as cell culture studies; (v) possible mechanisms explaining the osteoprotective effects of green tea bioactive compounds; (vi) other bioactive components in tea that benefit bone health; and (vii) a summary and future direction of green tea and bone health research and the translational aspects. In general, tea and its bioactive components might decrease the risk of fracture by improving bone mineral density and supporting osteoblastic activities while suppressing osteoclastic activities. 相似文献
103.
目的研究hTERT反义基因对舌鳞癌Tca8113细胞株的影响.方法应用RT-PCR法获得反义hTERT基因并转染舌鳞癌细胞,采用TRAP-DNA测序法检测转染前后细胞的端粒酶活性,并对细胞生长速度和倍增时间进行比较.结果转染后细胞的端粒酶活性及生长速度较转染前明显下降.结论 hTERT反义基因的表达可显著抑制舌鳞癌细胞的端粒酶活性和生长速度. 相似文献
104.
Paula J. Durlach Robert Edmunds Louise Howard Steven P. Tipper 《Nutritional neuroscience》2013,16(6):433-442
AbstractThough consumers of tea and coffee can report feeling beneficial subjective effects of consumption virtually immediately, tests for objective effects of caffeine immediately post-consumption have been rare. Two experiments examined caffeine's ability to influence reaction time in choice reaction time tasks, using a dose of caffeine typical of a cup of tea or instant coffee, and testing at short post-consumption delays. Two groups of participants were given 60 mg of caffeine, after overnight abstinence, either in a hot tea drink, or a hot water drink. Two control groups also received hot tea or water, but without caffeine. In Experiment 1, participants were given a keypress task before the drink (baseline), immediately after the drink, and 40 min after the drink. In Experiment 2, a touch-screen test was given either 1, 14, or 27 min post consumption. Caffeine was found to reduce the effect of a distracter on reaction time in the keypress test and to reduce reaction time in a component of the touch-screen task; however, in neither experiment were these effects significantly modulated by post-consumption delay length. Thus, the speed of caffeine's action on psychomotor performance was shown to be on the order of minutes. 相似文献
105.
茶多酚抗肿瘤分子机理的国外研究新进展 总被引:4,自引:0,他引:4
从信号传导、基因表达、细胞周期和细胞凋亡四个方面综述了近两年来国外对茶多酚抗肿瘤作用研究的新进展。茶多酚通过影响激酶传导通路,抑制细胞外因子表达、转录因子NF-kappaB和激活蛋白-1(AP-1)活化及基因表达起到抗肿瘤之功效,通过活化caspase诱导肿瘤细胞凋亡;通过诱导细胞周期素依赖性蛋白激酶抑制物(cki)表达,抑制细胞周期素(cy-clin)和细胞周期素依赖性蛋白激酶(cdk)表达使细胞周期停滞于某一时期。 相似文献
106.
羟基喜树碱、平阳霉素、顺铂单独及联合应用对人舌癌细胞活性的影响 总被引:3,自引:1,他引:2
目的:观察体外应用羟基喜树碱(HCPT)、平阳霉素(PYM)、顺铂(DDP)三种药物单用和两两联合应用对人舌癌Tca8113细胞的生长抑制作用。方法:采用MTT法、细胞计数法、软琼脂克隆形成法及HE染色法,研究用药前后细胞增殖活性及形态的变化。结果:(1)三种药单用及两药合用对细胞均有很好的抑制作用,且以HCPT和PYM合用最强。(2)HCPT和PYM单用和合用可使细胞的群体倍增时间显著延长,克隆形成率显著降低,形态发生明显的变化。结论:HCPT对Tca8113细胞在体外有很好的抑制作用且与PYM合用效果更佳。 相似文献
107.
速效牙敏消对猴牙牙本质小管堵塞作用的实验研究 总被引:2,自引:1,他引:1
为观察速效牙敏消对牙本质小管是否有堵塞作用,采用猴牙作为研究对象,通过扫描电镜及电子探针能谱分析技术,发现用药3min即可出现堵塞现象,5min后可形成较明显的堵塞作用,10min后堵塞较完善,堵塞物为药物的主要成份.结果提示:应用此药5~10min便能达到比较完善的脱敏作用 相似文献
108.
研究了以碎茶为原料获得了在一次工艺中制取茶叶抗氧剂、咖啡碱、叶绿素的最佳工艺条件,并对茶多酚的纯度与抗氧性的关系,柠檬酸对茶多酚的抗氧增效作用进行了研究,指出茶多酚作为抗氧剂产品必须具有较高的纯度。 相似文献
109.
110.
目的 系统评价茶摄入与乳腺癌发病风险的关系。方法 计算机检索PubMed、EMBASE、EBSCO、The Cochrane Library、CNKI、SinoMed、万方和维普数据库,搜集有关茶摄入水平与乳腺癌关系的研究,检索时间截至2016年10月6日。按纳入标准选择文献、提取资料和进行方法学质量评价后,采用RevMan 5.3 软件进行 Meta 分析。结果 共纳入37篇研究,Meta分析结果显示,茶摄入可减小乳腺癌6%的发病风险(RR=0.937,95%CI:0.901~0.974,P=0.001)。亚组分析显示,茶摄入类型为绿茶的人群罹患乳腺癌的风险约下降12%(RR=0.885,95%CI:0.800~0.978,P=0.020);东亚人群茶摄入与欧美人群相比有明显的抑制乳腺癌的作用,可减少10%乳腺癌的发病风险(RR=0.901,95%CI:0.823~0.987,P=0.020)。结论 茶摄入能降低乳腺癌的发病风险,特别是东亚人群或茶摄入类型为绿茶时这种抑癌作用更加明显。 相似文献