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《Analytical letters》2012,45(4):605-614
A highly sensitive and simple method for determining cryptotanshinone (Cry), tanshinone I (Tan I), and tanshinone IIA (Tan IIA) in Salvia miltiorrhiza was developed using micro HPLC with electrochemical detection (µHPLC-ED). The tanshinones were extracted using an ultrasonic method, with methanol as the extractant. The separation was carried out on a C18 (150 mm × 1.0 mm i.d., 3 µm particle size) analytical column. The mobile phase was acetonitrile-water-formic acid mixture (52:48:0.6, v/v/v) solution. The flow rate and the temperature of the column were set at 30 µL/min and 35°C. The applied potential was set at ?0.4 V vs. Ag/AgCl. The peak heights for Cry, Tan I, and Tan IIA were found to be linearly related to the amounts injected, ranging from 0.145 µmol/L to 3.88 µmol/L, 0.226 µmol/L to 3.01 µmol/L, and 0.149 µmol/L to 3.98 µmol/L, respectively. The RSD values of intra-day precision and repeatability were not more than 3.0%, and the recovery of three analytes were ranged from 96.7% to 97.5%. The results of the method validation indicated that this method had good precision and accuracy. As such, the method was applied to analyze crude materials and decoction pieces of Salvia miltiorrhiza.  相似文献   
2.
隐丹参酮的电化学行为及其测定   总被引:2,自引:4,他引:2  
采用循环伏安法研究隐丹参酮在电极上的电化学行为及建立差示脉冲伏安对其测定的新方法。在pH 4.0乙酸盐缓冲液中,氧化峰电流与隐丹参酮浓度在3.0×10-8~2.0×10-7mol/L范围内呈良好的线性关系,检出限为2.0×10-9mol/L。玻碳电极可有效消除样品中其它组分对隐丹参酮测定的干扰,已用于实际样品中隐丹参酮的直接测定。该方法灵敏度高、检测范围宽。  相似文献   
3.
The reaction of cryptotanshinone and tanshinone IIA with several biogenic amine metabolites involved in the pathogenic pathways of HE were investigated and eight 1,2,3,4-tetrahydrophenanthrene derivatives,2-6 and 8-10,were obtained.The probable mechanism on reaction was discussed.  相似文献   
4.
采用二维相关光谱(2D-COS)技术,以氘代氯仿为溶剂,解析了丹参酮ⅡA和隐丹参酮标准品的近红外光谱(NIR)。丹参酮ⅡA和隐丹参酮二维相关切片谱在1 600~1 800,1 900~2 230和2 300~2 400 nm处有特征吸收,其中丹参酮ⅡA在1 640和2 140 nm处有不同于隐丹参酮的呋喃环双键一级倍频和组合频吸收,1 696 nm为丹参酮ⅡA和隐丹参酮分子中甲基伸缩振动二级倍频,1 726和1 740 nm处吸收为丹参酮ⅡA和隐丹参酮环己烯亚甲基伸缩振动二级倍频,2 146和2 220 nm为丹参酮ⅡA和隐丹参酮苯环C—C伸缩振动与C—H伸缩振动的组合频,2 300~2 400 nm处一系列峰为丹参酮ⅡA和隐丹参酮甲基伸缩振动与弯曲振动组合频吸收。以丹参酮提取物为载体,以丹参酮ⅡA和隐丹参酮光谱解析特征波段及组合间隔偏最小二乘(SiPLS)筛选特征波段分别建立偏最小二乘(PLS)定量模型,模型的决定系数R2均大于0.9,校正均方根误差(root mean of square error of calibration, RMSEC)和交叉验证均方根误差(RMSECV),预测均方根误差(RMSEP)均较小。结果表明,2D-COS技术解析特征波段与SiPLS波段筛选所建PLS模型均稳定。2D-COS技术使近红外定量模型更具解释性,可解析出结构差异特征吸收,同一波段可实现结构类似物的同时定量测定。  相似文献   
5.
The reactions of cryptotanshinone and tanshinone llA with cadaverine and putrescine were investigated. Six new compounds, four with imidazole functional groups and two with oxazole groups, were obtained. The possible reaction mechanism was proposed.  相似文献   
6.
Cryptotanshinone is the major active component from the root of Salvia miltiorrhiza which has been widely used for the management of coronary heart disease. The aims of this study were to develop and validate an HPLC method for the determination of cryptotanshinone in the human intestinal cell line Caco-2 monolayers, and to investigate the transport kinetics of cryptotanshinone. The developed HPLC method was sensitive and reliable, with acceptable accuracy (90–110% of true values) and precision (intra- and inter-assay CV < 10%). The total running time was within 10 min, with acceptable separation of the compounds of interest. The limit of quantitation (LOQ) for cryptotanshinone was 10 ng mL−1. A simple liquid–liquid extraction procedures resulted in an extraction efficiency of 90.8 ± 8.9 and 93.5 ± 6.2% for cryptotanshinone at 0.1 and 3 μg mL−1. The calibration curve was linear over the concentration range of 0.05–3.0 μg mL−1 with the mean correlation coefficients >0.999. The validated HPLC method was applied to examine the epithelial transport of cryptotanshinone by Caco-2 monolayers. The transport across the monolayers from the apical (B) to basolateral (A) side was significantly higher than that from A to B side. The structural analog of cryptotanshinone and a known substrate of P-glycoprotein, tanshinone IIA, dramatically inhibited the B to A transport of cryptotanshinone in the monolayers. These results indicate that the developed HPLC method was suitable for the study of transport of cryptotanshinone by Caco-2 monolayers and cryptotanshinone is a substrate of P-glycoprotein.  相似文献   
7.
(±)-Cryptotanshinone and its simplified analogues were synthesized via SmI2 promoted radical cyclization to construct the furan ring. Analogues 18 and 26 were identified as effective inhibitors of dual specificity protein phosphatase CDC25B which is a key enzyme for cell cycle progression, and they also inhibited growth in A-549 human lung cancer cell line.  相似文献   
8.
隐丹参酮和丹参酮IIA滤纸基质室温磷光法的研究   总被引:1,自引:0,他引:1  
考察了隐丹参酮和丹参酮 IIA的滤纸基质室温磷光法 ( PS- RTP)特性。选择Cd( Ac) 2 作为重原子微扰剂 ,对影响这两种丹参酮类化合物发光强度的各种因素进行了详细研究。同时建立了隐丹参酮和丹参酮 IIA的 PS- RTP分析测定的新方法  相似文献   
9.
Abnormal aggregation of amyloid-β (Aβ) peptides and associated inflammation and apoptosis in cerebrovascular endothelial cells are prelude to inhibition of onset of vascular dementia (VaD). Although small molecules have been widely used to mitigate the cell damage induced by aggregated species of Aβ, its molecular mechanism based on anti-amyloid properties and corresponding mitigation of cytotoxicity against cerebrovascular endothelial cells have not been elucidated. Herein, we used cryptotanshinone as the major bioactive compound from the root of Salvia miltiorrhiza Bunge to effectively inhibit Aβ fibrillation and associated cytotoxicity. Thoflavin T (ThT) and 1-Anilino-8-naphthalene sulfonate (ANS) fluorescence, Congo red, and circular dichroism (CD) analyses indicted that cryptotanshinone potentially inhibit Aβ1-42 aggregation through elongation of nucleation phase, apparent decrease in the slope of the growth phase, and the final fluorescence intensity in a concentration-dependent manner. Also, cell viability, inflammation and capsae-3 assays showed that co-incubation of Aβ1-42 peptide with cryptotanshinone in the aggregation buffer not only mitigated their cytotoxicity, but also reduced the levels of TNF-α, IL-1β, IL-6 and caspase-3 activity in cerebrovascular endothelial cells induced by Aβ1-42. This study suggested that cryptotanshinone may show a great promise in the development of small molecule-based platforms for the treatment of VaD.  相似文献   
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