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61.
Tea is a famous beverage that is produced from leaves of Camellia sinensis. Amongst the six major tea categories in China, dark tea is the only one that involves microbial fermentation in the manufacturing process, which contributes unique flavors and functions for the tea. In the recent decade, the reports about the biofunctions of dark teas have increased rapidly. Therefore it may be the proper time to consider dark tea as one potential homology of medicine and food. In this viewpoint, our current understanding of the chemical constituents, biological activities and possible health beneficial effects of dark teas were introduced. Some future directions and challenges to the development perspectives of dark teas were also discussed. 相似文献
62.
目的:观察高良姜、大高良姜、红豆蔻黄酮类成分对胃溃疡寒证大鼠环核苷酸水平及交感神经-肾上腺轴的影响,探讨3味山姜属中药温热药性的物质基础。方法:采用灌服冰知母水煎液与15%冰乙酸制备大鼠胃溃疡寒证模型,以干姜姜辣素为阳性对照,采用酶联免疫吸附试验(ELISA)法测定腺苷酸环化酶(AC)、磷酸二酯酶2(PDE2)、环磷酸腺苷(cAMP)、环磷酸鸟苷(cGMP)、促肾上腺皮质激素(ACTH)、多巴胺β羟化酶(D-β-H)含量。结果:与空白组比较,胃溃疡寒证模型组大鼠胃组织AC、cAMP含量及cAMP/cGMP比值显著降低,PDE2含量显著升高(P<0.01)。与模型组比较,高良姜、大高良姜、红豆蔻高低剂量组大鼠胃组织AC含量升高;高良姜、大高良姜、红豆蔻高低剂量组大鼠胃组织PDE2含量显著降低,cAMP含量、cAMP/cGMP比值显著升高(P<0.01或P<0.05)。结论:3味山姜属中药黄酮类成分通过调节胃溃疡寒证大鼠环核苷酸水平从而促进交感神经-肾上腺轴功能活动的作用,也体现出黄酮类成分药性温热。 相似文献
63.
Objective: To establish a method for directional screening of the cytotoxic components from the medicinal herb of Achnatherum inebrians by a combination of surface plasmon resonance (SPR) biosensor and chromatographic isolation technology.
Methods: Under the guidance of bioactive assessment based on binding abilities between objects and the α-Mannosidase (α-Man) target, the active components from different solvents extracts, different polar extraction parts and fractions were screened orderly and directionally using SPR. Components with a high binding ability to α-Man can be precisely oriented in a narrower fractions range and are easy to isolate. Three human cancer cells were used to evaluate the cytotoxic activity of component with the highest affinity to α-Man.
Results: Eight compounds were isolated and identificated from A. inebrians for the first time. Deoxyvasicinone possessed the highest affinity to α-Man among them. Moreover, deoxyvasicinone showed good effects on inhibited proliferation of human hepatoma cells HepG2 (IC50 = 5.7 μmol/L), human breast cancer cells MCF7 (IC50 = 7.21 μmol/L) and human lung cancer cells HCC827 (IC50 = 0.75 μmol/L), respectively. In particular, its inhibitory effect on HCC827 was stronger than the positive drug gefitinib (IC50 = 1.65 μmol/L).
Conclusion: A comprehensive strategy of directional screening potential cytotoxic components from herb based on biomolecular interaction and chromatography was established. Deoxyvasicinone as an effective anti-cancer component was initially isolated from A. inebrians. It is expected that this screening strategy could provide new perspectives for rapid screening and identification of active components from natural plants with the complex matrix. 相似文献
64.
目的 了解扬州市食品中化学污染物及有害因素的污染状况,确定风险因子的可能来源及分布,为食品安全防控工作提供数据依据。方法 依据每年扬州市《食品安全风险监测方案》,2015—2019年在扬州市辖区内采集食品样品,并进行相关化学污染物及有害因素的检测。结果 5年共检测23大类1 311份食品样品208个指标,样品合格率为97.79%;其中8类29份食品样品中13个指标超标,样品超标率为2.21%。不合格指标为蔬菜中农药残留和镉、茶叶和水果中农药残留、水产动物中总砷、藻类中铅、粉丝和油条中含铝添加剂、小麦制品中脱氧雪腐镰刀菌烯醇、蜂蜜中甲硝唑。结论 扬州市食品中的化学污染情况总体较好,但部分食品中仍存在污染物超标现象,应引起相关部门的重视。 相似文献
65.
R. Romand M. Dauzat 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1982,45(1-2):265-268
Summary The spontaneous activity of primary vestibular neurons was studied during postnatal development in the cat. Activities were categorized as regular, intermediate and irregular on the basis of the coefficient of variation. At birth, few regularly firing units were found while the percentage of intermediate and irregular units was high. During development, the percentage of units meeting the criterion of regularity increased steadily with age. At the same time the number of intermediate and irregular units decreased. The average resting rate of all categories of unit showed an increase in firing from birth up to the adult stage, i. e., around the second postnatal month. The mean firing rate of regularly firing units was always higher than the two other categories throughout all the stages of development. These results were compared with similar work performed in the rat.Supported by grants from the C.N.R.S. (E.R.A.-187) and D.G.R.S.T. (no. 79-7-1073) 相似文献
66.
Dr M. C. T. Denyer M. Riehle S. T. Britland A. Offenhauser 《Medical & biological engineering & computing》1998,36(5):638-644
There are a range of techniques that can be used to assay bioactive compound. One potentially promising technique is a system
consisting of microfabricated extracellular recording devices over which electrogenic cells can be grown. To date, research
in this area has concentrated on the use of neurons as an electrogenic cell type. However, these cells have limitations. Only
small extracellular potentials have been recorded from mammalian neurons cultured over microfabricated electrode arrays. Although
such potentials may be of use in assays examining the effects of bio-active compound analogues on firing frequency, they are
of little use for more detailed pharmacological studies involving analyses of signal shape. What is required is a system from
which much larger extracellular potentials can be recorded. This preliminary study reports on a system based on cardiac myocytes
cultured over microfabricated metal microelectrode arrays, from which potentials with a mean amplitude of 16.9 μV can be reliably
recorded, which can be reversibly blocked with μmoll−1 concentrations of the sodium ion channel blocker lidocaine. Less common potentials with amplitudes of up to 3.5 mV were also
recorded. It is demonstrated that cardiac myocytes cultured over microfabricated micro-electrode arrays can be used in assays
of cardioactive compound analogues. 相似文献
67.
Francesco Tedesco Maria A. Villa Peter Densen Girolamo Sirchia 《Molecular immunology》1983,20(1):47-51
Structural and functional studies were performed on a dysfunctional C8 molecule present in the serum of two siblings and an unrelated individual. The C8 in these three sera exhibited a pattern of partial immunologic identity with C8 in normal serum but was devoid of functional activity. The C8 was immunoprecipitated from the three sera and from a control serum with an antihuman C8 antiserum and analyzed by SDS-PAGE using highly purified human C8 as a reference. A selective absence of a band of 62,000 mol. wt was observed in the immunoprecipitates from the sera containing dysfunctional C8. Experiments performed with the purified α-γ and γ subunits showed that the hemolytic activity of the C8 deficient sera could be reconstituted by the addition of the β chain but not the α-γ dimer. Binding of the dysfunctional C8 to C was excluded by the following observations: (1) EAC 1–7 treated with the C8 deficient sera and then washed could not be lysed after the addition of the β subunit and C9; and (2) the abnormal molecules did not interfere with the consumption of normal C8 by the soluble complex SC5b-7. 相似文献
68.
研究国内来源于地榆属8个不同种、变种与变型的地榆及2种混淆品的生药性状、组织构造及其粉末的鉴别特征,并分别列出生药性状、组织构造及粉末特征的检索表。 相似文献
69.
为在国内开发治疗妇女更年期与手术后绝经症的新药 ,对国产替勃龙进行了多项生殖内分泌生物实验 ,结果表明该药兼具雌激素、孕激素及雄激素活性 ,并有延迟排卵作用 ,对大鼠雌激素缺乏性阴道炎也有治疗作用。其药理特性符合临床治疗女性更年期综合症要求。 相似文献
70.
Ziggi Ivan Santini Lau Caspar Thygesen Steinar Krokstad Lars Ole Bonde Robert J. Donovan Vibeke Koushede Anita Jensen Ai Koyanagi Ola Ekholm 《British journal of health psychology》2023,28(3):844-859