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排序方式: 共有115条查询结果,搜索用时 453 毫秒
91.
中药材中常因含有一定量的重金属元素而使其质量受到影响。采用火焰原子吸收分光光度法测定几种常用中药材提取前后金属元素铜、铅、镉、锰、锌、铁的含量变化。结果表明,大部分中药材提取后金属元素含量均有不同程度的下降,这为去除中药材中的铅、铜等重金属提供了参考依据。 相似文献
92.
ICP-OES和ICP-MS法研究中草药中元素的溶出特性 总被引:1,自引:0,他引:1
中药中微量元素的含量,尤其是有毒重金属的含量日益引起人们的重视[1].测定中草药原生药金属元素含量的报道较多[2-7],而系统研究煎煮前后微量元素分布的报道较少[8-12].本文选取了常用配方中最常用的十八种中草药,采用电感耦合等离子体原子发射光谱法(ICP-OES)和电感耦合等离子体质谱法(ICP-MS)对其中的Al、Ca、Fe、K、Mg、Mn、Na、Sr、Zn、V、Ni、Cu、Cd和Pb等14种金属元素煎煮溶出的情况进行了初步研究,试图为中药研究提供一些基础数据. 相似文献
93.
植物类中药中微量元素的因子分析和聚类分析 总被引:40,自引:0,他引:40
尝试利用化学计量学方法探讨微量元素含量与中药药性的相关性。对105味植物类中药42种微量元素测定数据用因子分析和聚类分析进行了多因素分析。因子分析证实了一个10因子模型合理解释这些微量元素间的相关关系;样本聚类分析证明了105株中药合理地聚类成不同组; 相似文献
94.
中药黄连有效成分盐酸小檗碱与牛血清白蛋白的相互作用 总被引:27,自引:0,他引:27
从天然中药材黄连中提取分离并精制得到盐酸小檗碱(BC),采用UV光谱和荧光光谱(FS)研究其与牛血清白蛋白(BSA)的相互作用,解释了BC导致BSA的荧光发射光谱峰裂分的现象,其二重峰分别归属于色氨酸及酪氨酸残基.结果表明,静态猝灭和非辐射能量转移是导致BC对BSA荧光猝灭的两大原因,BC与BSA的表观结合常数KA为8.66×104L/mol(30℃)和8.72×104L/mol(37℃),BC在BSA分子上的结合位点数为(3.1±0.2).BC与BSA分子中荧光性氨基酸残基之间的距离为3.75nm(30℃)和3.62nm(37℃),表明BC的部分片段能够插入BSA分子内部.热力学函数计算结果表明,该作用过程是一个熵增加、Gibbs自由能降低的自发超分子作用过程,并由此推断BC与BSA之间以疏水相互作用为主. 相似文献
95.
微波消解-水杨基荧光酮光度法测定中草药中痕量锗 总被引:1,自引:0,他引:1
在H3PO4介质中,以水杨基荧光酮为显色剂,以吐温-80为表面活性剂,研究了微波消解部分清热解毒类中草药中痕量锗的测定条件.水杨基荧光酮与锗(Ⅳ)的配合物的最大吸收峰为506 nm,表观摩尔吸光系数为ε=1.54×105 L·mol-1·cm-1,回归方程A=0.0409ρ 0.00614,相关系数 r=0.9999,检出极限为0.014 μg/mL. 相似文献
96.
Abdollah Ardebili Mohammad Hassan Pouriayevali Sahar Aleshikh Marziyeh Zahani Mehdi Ajorloo Ahdieh Izanloo Abolghasem Siyadatpanah Hadi Razavi Nikoo Polrat Wilairatana Henrique Douglas Melo Coutinho 《Molecules (Basel, Switzerland)》2021,26(22)
The treatment of viral disease has become a medical challenge because of the increasing incidence and prevalence of human viral pathogens, as well as the lack of viable treatment alternatives, including plant-derived strategies. This review attempts to investigate the trends of research on in vitro antiviral effects of curcumin against different classes of human viral pathogens worldwide. Various electronic databases, including PubMed, Scopus, Web of Science, and Google Scholar were searched for published English articles evaluating the anti-viral activity of curcumin. Data were then extracted and analyzed. The forty-three studies (published from 1993 to 2020) that were identified contain data for 24 different viruses. The 50% cytotoxic concentration (CC50), 50% effective/inhibitory concentration (EC50/IC50), and stimulation index (SI) parameters showed that curcumin had antiviral activity against viruses causing diseases in humans. Data presented in this review highlight the potential antiviral applications of curcumin and open new avenues for further experiments on the clinical applications of curcumin and its derivatives. 相似文献
97.
98.
Arumugam Vijaya Anand Balasubramanian Balamuralikrishnan Mohandass Kaviya Kathirvel Bharathi Aluru Parithathvi Meyyazhagan Arun Nachiappan Senthilkumar Shanmugam Velayuthaprabhu Muthukrishnan Saradhadevi Naif Abdullah Al-Dhabi Mariadhas Valan Arasu Mohammad Iqbal Yatoo Ruchi Tiwari Kuldeep Dhama 《Molecules (Basel, Switzerland)》2021,26(6)
The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome corona virus-2 (SARS-CoV-2), is the most important health issue, internationally. With no specific and effective antiviral therapy for COVID-19, new or repurposed antiviral are urgently needed. Phytochemicals pose a ray of hope for human health during this pandemic, and a great deal of research is concentrated on it. Phytochemicals have been used as antiviral agents against several viruses since they could inhibit several viruses via different mechanisms of direct inhibition either at the viral entry point or the replication stages and via immunomodulation potentials. Recent evidence also suggests that some plants and its components have shown promising antiviral properties against SARS-CoV-2. This review summarizes certain phytochemical agents along with their mode of actions and potential antiviral activities against important viral pathogens. A special focus has been given on medicinal plants and their extracts as well as herbs which have shown promising results to combat SARS-CoV-2 infection and can be useful in treating patients with COVID-19 as alternatives for treatment under phytotherapy approaches during this devastating pandemic situation. 相似文献
99.
The immune modulating effects of selected herbs deserve careful studies to gain evidence-based support for their further development. We have been working hard on many items of medicinal herbs to gain insight into their immunomodulatory effects relevant to cancer treatment in particular, while infection control is not excluded. Nine of them have been selected to give the results of our exploration on their biological, particularly immunomodulatory activities. Since Hong Kong people especially favor one medicinal mushroom, viz. Coriolus versicolor, a number of clinical trials using Coriolus for cancer-related studies are included in this review. While immune modulation platforms are being built for relevant studies, a brief account on the research targets and related procedures are given. 相似文献
100.
《Journal of mass spectrometry : JMS》2017,52(2):116-126
The paper focuses on the optimization, settings and validation of direct analysis in real time coupled with time‐of‐flight detector when used for the evaluation of the quality of selected herbal teas (fennel, chamomile, nettle, linden, peppermint, thyme, lemon balm, marigold, sage, rose hip and St. John's wort). The ionization mode, the optimal ionization temperature and the type of solvent for sample extraction were optimized. The characteristic compounds of the analysed herbal teas (glycosides, flavonoids and phenolic and terpenic substances, such as chamazulene, anethole, menthol, thymol, salviol and hypericin) were detected. The obtained mass spectra were evaluated by multidimensional chemometric methods, such as cluster analysis, linear discriminate analysis and principal component analysis. The chemometric methods showed that the single variety herbal teas were grouped according to their taxonomic affiliation. The developed method is suitable for quick identification of herbs and can be potentially used for assessing the quality and authenticity of herbal teas. Direct analysis in real time/time‐of‐flight‐MS is also suitable for the evaluation of selected substances contained in the mentioned herbs and herbal products. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献