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31.
用乙醇和乙酸乙酯为溶剂提取松溪绿茶,获得乙醇绿茶提取物和乙酸乙酯绿菘提取物. 这两种提取物茶多酚含量分别为68.75%(乙醇)和96.5%(乙酸乙酯),并对豆油、菜油、棕榈油、 花生油、猪油均有良好的抗氧化活性,在威化饼干夹心油脂的感官审评中,也呈现很好的抗氧化效果. 相似文献
32.
云南天然饮料物中的微量元素分析 总被引:7,自引:1,他引:7
用原子吸收光谱法测定了云南的茶叶、三七叶、茎及咖啡豆中的微量元素Zn,Cu,Co,Mn,Fe,Ca,Mg,K的含量;分光光度法测定Mo的含量,根据实验结果讨论与人体健康的关系. 相似文献
33.
信阳绿茶茶多酚含量及浸出率 总被引:2,自引:0,他引:2
本文采用酒石酸亚铁比色法对优质信阳毛尖和次等茶叶中茶多酚含量进行测定,并探讨冲泡水温和冲泡时间对茶多酚浸出率的影响。实验结果表明:优质毛尖和次等茶叶的TP含量分别为21.96%-23.52%和17.98%-19.26%。冲泡水温度和冲泡时间对TP浸出率均有显著影响。 相似文献
34.
医学史著作在论说佛教医学对于日本的影响时,大多是顾名思义地从现代有关茶之保健作用的认识角度,评价镰仓时代(1192—1333年)僧人荣西所著《吃茶养生记》的医学价值。另一方面,在诸多有关“茶文化”的著作中,也同样可以看到对于荣西及该书重要历史地位与作用的论说——不仅是中国茶文化的传播者,而且是日本“茶道”的先驱。但实际上,该书的上卷是在佛教思想的指导下,将所有疾病的原因都解释为源于“心”,同时借助中国医学理论言说苦味对于“心”的重要作用,构建起佛教教义与世俗医学理论、脏器之“心”与精神之“心”一体化的理论解释和治疗方法;下卷又从鬼魅作祟的角度解释一些疑难病症的原因,提倡使用具有“灵气”的桑作为治疗药物。上下两卷构成了一个包含外治(苦味)与内治(神灵)两面的完整宗教医学体系。其后逐渐形成的茶道,也同样不是着眼于茶的保健作用。“茶”在“茶道”中,仅仅是一个道具。 相似文献
35.
ZENGXiaomei SHIXiaobing SHENYungang 《科学通报(英文版)》2004,49(3):258-262
The ε subunit of the chloroplast ATP synthase and the truncated ε mutants which lack some amino acid residues from the N-terminus or C-terminus were overexpressed in E. coil When the ε subunit or the truncated ε proteins was added to the spinach chloroplast suspension, both the intensity of the fast phase of millisecond delayed light emission (ms-DLE) and the cyclic and noncyclic photophosphorylation activity of chloroplast were enhanced. With an increase in the number of residues deleted from the N-terminus, the enhancement effect of the N-terminal truncated proteins decreased gradually. For the C-terminal truncated proteins, the enhancement effect increased gradually with an increase in the number of residues deleted from the C-terminus. Besides, the ATP synthesis activity of ε-deficient membrane reconstituted with the ε subunit or the truncated ε proteins was compared. The ATP synthesis activity of reconstituted membrane with the N-terminal truncated proteins decreased gradually as the number of residues deleted from the N-terminus increased. For the C-terminal truncated proteins, the ATP synthesis activity of reconstituted membrane increased gradually with an increase in the number of residues deleted from the C-terminus, but was still lower than that of the wild type ε protein. These results suggested that: (a) the N-terminal domain of the ε subunit of the chloroplast ATP synthase could affect the ATP synthesis activity of ATP synthase by regulating the efficiency of blocking proton leakage of ε subunit; and (b) the C-terminal domain of the ε subunit of the chloroplast ATP synthase had a subtle function in modulating the ATP synthesis ability of ATP synthase. 相似文献
36.
Enzymes and receptors in the leukotriene cascade 总被引:7,自引:0,他引:7
Leukotrienes are a family of paracrine hormones derived from the oxidative metabolism of arachidonic acid. These lipid mediators
are recognized as important signal molecules in a variety of inflammatory and allergic conditions affecting the skin, joints,
gastrointestinal and respiratory systems, in particular asthma. Such conditions are typified by local pain, tissue edema,
hyperemia and functional losses. In the tissues, immunocompetent cells accumulate at the site of injury which contribute to
tissue damage and perpetuation of the disease process. Leukotrienes can elicit most, if not all, of these signs and symptoms.
Thus, leukotriene B4 is one of the most powerful chemotactic agents known to date and participates in the recruitment of leukocytes. The cysteinyl
leukotrienes, on the other hand, contract smooth muscles, particularly in the peripheral airways and microcirculation. Recently,
drugs which block the formation and action of leukotrienes have been introduced as novel antiasthmatic medications. This chapter
reviews the biochemistry, molecular biology and cell biology of the key enzymes and cognate receptors in the leukotriene cascade. 相似文献
37.
Arginase expression in peritoneal macrophages and increase in circulating polyamine levels in mice infected with Schistosoma mansoni 总被引:5,自引:0,他引:5
Abdallahi OM Bensalem H Augier R Diagana M De Reggi M Gharib B 《Cellular and molecular life sciences : CMLS》2001,58(9):1350-1357
We investigated the nitric oxide (NO) synthase and arginase pathways in resident peritoneal macrophages of mice infected
with the tropical parasite Schistosoma mansoni. The two enzymes may have opposite effects, insofar as NO may be involved in the killing of the parasite whereas arginase
may stimulate parasite growth via polyamine synthesis. We determined the effects of the infection on the expression and activity
of the two enzymes in macrophages, before and after cytokine activation. Cells from infected mice expressed the hepatic type
I arginase, whereas in control cells, the enzyme was expressed only after cytokine activation, as were NO synthase II and
type II arginase in both groups of cells. Moreover, we found that in infected mice, arginase expression in macrophages was
associated with a ten fold increase in the concentration of circulating ornithine-derived polyamines. This may be of pathological
importance, since parasitic helminths are though to be dependent on their hosts for the uptake and interconversion of polyamines.
Received 13 March 2001; received after revision 4 May 2001; accepted 7 June 2001 相似文献
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为研究武夷冻茶霉菌的分布情况,采用镜相分析和PCR(polymerase chain reaction)技术对霉菌进行菌相分析及优势菌种鉴定。结果表明,冻茶中主要菌属有曲霉属、毛霉属、根霉属和青霉属,其中青霉属为优势菌属;对随机分离纯化的青霉进行ITSrDNA鉴定,鉴定结果为壳青霉(Penicillium.crustosum Thom)。分析结果可为微生物污染途径分析以及改进冻茶的冷藏工艺条件提供理论依据。 相似文献