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51.
Summary A high-performance liquid chromatographic method for the separation and determination of gastrodin,p-hydroxybenzyl alcohol, vanillyl alcohol,p-hydroxylbenzaldehyde and vanillin in extract of Chinese herbal medicine tall gastrodia tuber (Chinese name: Tianma) was established. The chromatographic conditions were optimized by means of computer-assisted method development technique. Dry-Lab software was used to model the retention behavior of the compounds as a function of gradient conditions, based on the data from two scouting gradient runs. Under the optimized conditions: column, Kromasil-C18, 5 μm, 15×0.46-cm; solvent A, water; solvent B, methanol; gradient, 5/44/65/65% B at 0/9/12/15 min; flow rate, 1.00 mL min−1; temperature, ambient, the quality of tall gastrodia tubers from different sources and tianma injection were examined.  相似文献   
52.
老年人由于组织器官的老化和功能减退,影响药物的吸收、分布、代谢和排泄。为确保老年患者的用药安全,应提高老年人的合理用药水平。  相似文献   
53.
碘酸钾存在下极谱催化波法测定陈皮甙   总被引:2,自引:0,他引:2  
过玮  何盈盈  许昭  宋俊峰 《分析化学》2002,30(2):202-203
基于陈皮甙在KIO3存在下产生的极谱催化波,拟定了测定陈皮甙的新方法。在 0.55 mol/L HAc-0.01mol/L NaAc(pH 4.00±0.05)-1.0×10~(-3)mol/L KIO3缓冲溶液中,陈皮甙催化波的峰电位为-1.35 V(vs,SCE),它的一阶导数峰峰电流与陈皮甙浓度在2.6 × 10~(-7)~2.6 × 10~(-6)mol/L范围内呈线性关系(r=0.9970,n=6)。本方法比现有的电化学方法灵敏度高一个数量级。可用于直接测定中草药贯众水提液中陈皮甙含量。  相似文献   
54.
In the paper, two main methods, which are Serum Pharmacology and Traditional Pharmacology, were adopted to study Chinese traditional medicine, such as Ginkgo biloba extract (GBE), ginsenosides (GS) and compound GG (GBE + GS), pharmacology in vitro. The results showed that there were evident difference between the results of Serum Pharmacology and that of Traditional Pharmacology. There was no significant difference between the drug effect of crude GS on nitric oxide (NO) production in ECV304 and that of crude GBE, and the drug effect of GG was superior to that of GS and GBE, respectively. But, compared with GBE serum, the GS serum up-regulation of NO production in ECV304 increased significantly, and the GG serum up-regulation of the NO production in ECV304 was inferior to that of GS serum and GBE serum significantly. The results suggested that Serum Pharmacological study should be adopted in the pharmacological investigation on the Chinese traditional medicine and the drug screening of the Chinese traditional medicine.  相似文献   
55.
一种用于中药纯化过程的近红外光谱分析新方法   总被引:36,自引:0,他引:36  
针对中药大孔吸附树脂纯化过程缺乏在线检测分析手段等问题,提出基于光纤 近红外透射光谱的过程分析新方法.以黄连提取物为例,采用HPLC分析测定值作参 比,用偏最小二乘算法建立了近红外透射光谱校正模型,并成功地用于预测黄连生 物碱在大孔树脂纯化过程中的洗脱曲线.本方法实时、快速,可同时测定洗脱物中 盐酸小檗碱、盐酸巴马亭、盐酸药相碱和黄连总生物碱的浓度.预测精度满足工业 过程分析要求,为提高中药质量分析水平提供了新的途径.  相似文献   
56.
柳一鸣  欧阳健明  邓芳  郑辉 《化学学报》2006,64(14):1446-1450
采用扫描电子显微镜(SEM)和X射线衍射法(XRD)研究了土家族药物天葵化石汤(Tiankui)的提取液对尿石晶体草酸钙(CaOxa)成核、生长的抑制作用及其对二水草酸钙(COD)的稳定作用. 当Tiankui浓度小于30 mg/mL时, 主要生成一水草酸钙(COM), 但可使COM晶体棱角圆钝. 随着Tiankui浓度增加至45和75 mg/mL, 可分别诱导95%和100%的COD晶体生成. Tiankui还可以稳定COD在水溶液中的存在, 没有Tiankui存在时, COD在48 h内全部转化为COM晶体, 而在12 mg/mL Tiankui存在下, COD仅有20%转化. 从Tiankui提取液的活性组分、与草酸钙不同晶相间的吸附差异、化学配位等角度讨论了其抑制CaOxa生长和诱导稳定COD的化学基础.  相似文献   
57.
In this study, a fingerprint-activity relationship modeling between chemical fingerprints and antirheumatic activity was established, and multivariate statistical analysis was used to evaluate the quality of Taxilli Herba (TH) from different hosts. Characteristic fingerprints of 20 batches of TH samples were generated by high-performance liquid chromatography coupled with triple quadrupole-time of flight tandem mass spectrometry (HPLC-Triple TOF-MS/MS), and the similarity analysis was calculated based on thirteen common characteristic peaks by hierarchical clustering analysis (HCA). Subsequently, nine efficacy markers were discovered by combining fingerprints and antirheumatic activity through grey correlation analysis (GCA) and bivariate correlation analysis (BCA). Meanwhile, the content of 5 constituents in 9 markers was determined by high-performance liquid chromatography coupled with triple quadrupole-linear ion trap tandem mass spectrometry (HPLC-QTRAP-MS/MS). The comprehensive quality of TH was assessed using multivariate statistical analysis, including principal components analysis (PCA) and technique for order preference by similarity to ideal solution (TOPSIS). The results showed that a high dose of TH extract could markedly ameliorate arthritis damage compared to other doses, with flavonoids playing an important role in the antirheumatic activity. The comprehensive quality of samples from Morus alba L. (SS) was superior to those from Liquidambar formosana Hance (FXS). The present study will demonstrate the markers associated with efficacy, and provide an applicable strategy for more comprehensive quality control and evaluation of TH.  相似文献   
58.
ComputerHandlingofChemicalandBiologicalDataofTraditionalChineseMedicinesCHEChun-taoa**,PaulR.CarlieraandOpheliaC.W.Leeb(aDepa...  相似文献   
59.
Agastache rugosa Kuntze (Korean mint) is used as a spice and in folk medicine in East Asia. The present study identified a total of 18 polyphenols from the flower, leaf, stem and roots of this plant using high‐performance liquid chromatography–tandem mass spectrometry. Fourteen of these compounds had not previously been identified in these plant tissues. Each polyphenol was validated in comparison with external calibration curves constructed using structurally related compounds, with determination coefficients >0.9993. The limits of detection and quantification were 0.092–0.650 and 0.307–2.167 mg/L, respectively. Recoveries of 61.92–116.44% were observed at two spiking levels, with 0.91–11% precision, expressed as relative standard deviation (except anthraquinone spiked at 10 mg/L). Hydroxycinnamic acid was the most abundant compound in the root, while the flowers showed the highest total flavonoid level. Antioxidant activities, determined in terms of reducing power, Fe2+ chelating activity and the radical scavenging activities using α,α‐diphenyl‐β‐picrylhydrazyl and 2‐2?‐azino‐bis‐3‐ethylbenzothiazoline‐6‐sulfonic acid, increased in a concentration‐dependent manner; the highest activity was identified in the stems, followed by leaves > flowers > roots. These findings indicate that A. rugosa is a good source of bioactive compounds and can be used as a functional food. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
60.
A UPLC‐TOF/MS‐based metabolomics method was established to explore the therapeutic mechanisms of rattan stems of S. chinensis (SCS) in Alzheimer's disease (AD). Experimental AD model was induced by intra‐hippocampal Aβ1–42 injection in rats. Cognitive function and oxidative stress condition in brain of AD rats were assessed using Morris water maze tests and antioxidant assays [malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH‐Px)], respectively. UPLC‐TOF/MS combined with multivariate statistical analysis were conducted to study the changes in metabolic networks in serum of rats. The results indicated that the AD model was established successfully and the inducement of Aβ1–42 caused a decline in spatial learning and memory of rats. The injection of Aβ1–42 in rat brains significantly elevated the level of MDA, and reduced SOD and GSH‐Px activities. In addition, SCS showed significant anti‐AD effects on model rats. A total of 30 metabolites were finally identified as potential biomarkers of AD and 14 of them had a significant recovery compared with the AD model after SCS administration. Changes in AD metabolite profiling were restored to different levels through the regulation of 13 pathways. This is first report on the use of the UPLC‐TOF/MS‐based serum metabolomics method to investigate therapeutic effects of SCS on AD, and enrich potential biomarkers and metabolic networks of AD.  相似文献   
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