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71.
微乳液增敏光度法测定中草药中微量硒 总被引:2,自引:1,他引:2
研究了在非离子微乳液介质中,硫氰酸盐罗丹明B 明胶体系分光光度法测定微量硒的方法。实验表明,当微乳液组成为V(OP乳化剂) +V(正戊醇) +V(正庚烷) +V(水) =1 5 0 +0 1 1+0 41 +97 98时,体系的表观摩尔吸收系数达1 3 0 1×1 0 6 L·mol- 1·cm- 1,灵敏度比在OP溶液中有显著提高,使该法成为少有的超高灵敏度测定硒的光度法之一。Se (Ⅳ)含量在0~0 0 5 μg·mL- 1范围内符合比耳定律,对0 0 2 μg·mL- 1Se(Ⅳ)平行测定1 1次,测得相对标准偏差为0 945 %。应用于中草药中微量硒的测定结果令人满意 相似文献
72.
《Arabian Journal of Chemistry》2022,15(11):104272
Yinlan lipid regulatory capsule (YL) is a composite traditional Chinese medicine (TCM) new drug to alleviate hyperlipidemia, while its therapeutic mechanism in vivo was not clarified with nontargeted metabolomics investigation. An animal model was established in rats fed a high-fat diet, and their body weights, body mass index (BMI) and blood cholesterol levels were measured. Serum, liver and kidney tissue samples were also extracted for PXR-CYP3A4-ABCB1-FXR signaling pathway research using PCR and UHPLC–MS. The obtained plasma samples were analyzed by UHPLC-Q-TOF-MS metabolomic investigation, which revealed PXR-CYP3A4-related metabolites and changes induced by YL. Finally, the key metabolites were chosen as index components, and their levels in the serum, liver, small intestine and bile were used for simultaneous UHPLC–MS-MS determination. The results indicated that YL was effective in rebalancing blood TG and TC levels (compared to controls). With respect to the PXR-CYP3A4-ABCB1 pathway, as a result of YL’s effect, gene expression or activity of the two targets decreased significantly in both the liver and kidney. The same trend was observed in the serum samples mentioned above. Metabolomics screening and data revealed that 44 metabolites can be regarded as biomarkers related to hyperlipidemia, fatty acids synthesis, and body energy consumption, as well as synthesis, transportation and exertion of cholesterol. YL’s treatment focused on 26 of them, primarily bile acids, indicating that the antihyperlipidemic effect of this drug lies in its inhibitory activity of cholesterol metabolism. Subsequent analysis of those in vivo components revealed that significant increases (compared to the model group) occurred in the blood, liver, small intestine and bile in groups that received medium and high doses of YL (while the low dose was relatively unchanged). Those target components exhibit a close relationship with PXR and/or CYP3A4. The use of YL repressed PXR expression and subsequently decreased CYP3A4 activity. As a result, synthesis of related bile acids increased, while cholesterol levels decreased, consequently leading to the attenuation of hyperlipidemia. This study comprehensively investigated the antihyperlipidemia mechanism of YL based on its repression of PXR-CYP3A4 activity and related metabolite yield, establishing an accurate method for evaluating the therapeutic effect of YL. 相似文献
73.
通过对两间小学639名学生进行微量元素检测及体格检查,并进行中医辩证分型,发现广州市部份小学生体内微量元素缺乏较严重,占体检总人数的62.3%,同时也存在营养不良,贫血、佝偻病,急慢性上呼吸道炎等、按中医辩证分型有肝热、脾气虚弱、肝血不足、肾气虚等,本文试从微量元素缺乏与中医辩证中找出两者之间的联系,以便于指导治疗,提高小学生的健康水平,增强体质和智力。 相似文献
74.
A three-dimensional pharmacophore model was developed from a series of inhibitors of Aurora A kinase to discover new potent anti-cancer agents using the HypoGen module in the Catalyst software. The pharmacophore model was developed based on the structure of 20 currently available inhibitors, which were carefully selected from the literature. The best hypothesis (Hypo 1) was defined by four features: one hydrogen-bond donor and three hy- drophobic points, with the best correlation coefficient of 0.909, the lowest rms deviation of 1.563, and the highest cost difference of 99.075. The Hypo 1 was then validated by a test set consisting of 24 compounds and by a cross-validation of 95% confidence level through randomizing the data using the CatScramble program, which suggested that a predictive pharmacophore model had been successfully obtained. 相似文献
75.
76.
应用中药材开发微量元素保健品 总被引:3,自引:0,他引:3
介绍了用中药村开发几种微量元素保健品,有补锌,有助小儿生长,补硒抗癌,补铁钴养血,补铬治糖尿病和补锌铅的肝病滋补保健品。 相似文献
77.
12种道地中药中无机元素的含量测定 总被引:1,自引:0,他引:1
报道了用X射线荧光分析法测定的12种道地中药,98个不同产地样品中的Fe、Cu、Zn、Mn、Sr、Ca、K含量。结果表明,不同种属,不同产地,不同品种中药元素量存在差异,不同加工方法影响中药中元素含量,同种中药中元素分布模式也不同。 相似文献
78.
D-氨基葡萄糖衍生物的研究进展 总被引:3,自引:0,他引:3
D-氨基葡萄糖作为甲壳素的最终降解产物参与构造人体组织和细胞膜,是蛋白多糖大分子合成的中间物质,具有多种生物活性.其分子内有多个反应中心(4个-OH和1个-NH2),对其进行化学修饰后可广泛应用于生物医药领域.作者综述了D-氨基葡萄糖衍生物的研究进展. 相似文献
79.
80.
综合分析近年来有关的中外文献资料,讨论了临床常用药物对肠道锌吸收的影响及其意义。有十几类药物会对锌吸收产生影响。药物对锌吸收的影响在营养学及其临床上有重要意义,其中对锌吸收的抑制可能是锌缺乏的原因之一。 相似文献