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61.
优选了复方烧伤膏的最佳醇提取工艺.以大黄素提取量、干膏率为评价指标,选择乙醇浓度、乙醇用量、提取时间及提取次数为考察因素,利用L9(34)正交实验确定复方烧伤膏的醇提取工艺.结果:最佳提取工艺为加70%的乙醇8倍量,回流提取3次,1h/次.优选出的提取工艺简单、可行,可作为该制剂合理开发的依据.  相似文献   
62.
IntroductionEmodinisoneoftheanthraquinonecompounds[1] ,whichexistsinmanymedicalplantssuchasradix polygonimultiflori,rhizomapolygoni,etc .Emodinisanimportantcompoundinmedicine .Ithasmanybiologicalactivitiessuchasanti infection ,decreasingbloodlipidscontent ,e…  相似文献   
63.
薄层色谱法测定大黄类药物与环糊精的包结常数   总被引:5,自引:0,他引:5  
以环糊精的水溶液为流动相,聚酰胺薄膜为固定相,用反相薄层色谱法研究了大黄有效成份大黄素、芦荟大黄素与环糊精的包结作用,测定了包结常数,环糊精对大黄类药物有明显的增溶作用,且环糊精与大黄类药物有明显的增溶作用,且环糊精与大黄类药物的包结作用符合熵补偿规律,补偿温度为296.5K;通过熵焓补偿规律得出,大黄类药物与环类精的包结过程中环糊精分子结构发生了较大的变化,同时经历了适中的去溶剂化步骤。  相似文献   
64.
采用量子化学从头算法,计算10个大黄素类似物分子结构参数,用逐步回归分析法筛选合适结构参数作为网络输入节点,建立大黄素类化合物抗乳腺癌(MCF-7)细胞活性的BP神经网络模型。研究表明,大黄素类化合物抗乳腺癌(MCF-7)细胞活性与分子中A环电荷和第3条最低空轨道能量相关,神经网络模型经留一法交叉验证,具有可信的预报能力。  相似文献   
65.
目的通过对烧伤喷雾剂中大黄素的含量测定,为制定烧伤喷雾剂质量标准提供依据。方法采用薄层扫描法;展开剂:苯-乙酸乙酯-甲酸-水(30:10:0.5:2.5)。结果烧伤喷雾剂中大黄素含量为2.03mg/mL,大黄素在0.2~8μg范围内呈良好线性关系,r=0.9979,平均回收率=97.83(n=6),RSD=2.81。结论测定结果准确、稳定、灵敏度高、重现性好,该法可作为烧伤喷雾剂质量标准的参考。  相似文献   
66.
大黄素是中药大黄的主要成分,也存在于虎杖、芦荟等药用植物中,是分布广泛的一种羟基蒽醌类化合物.其药理作用表现为抗肿瘤、扩张血管、抗菌、导泻、利尿等,具有很好的临床应用价值.结合本研究组的工作综述了大黄素的化学合成方法、结构修饰和生物活性等方面的新进展.  相似文献   
67.
A simple, sensitive and specific high-performance liquid chromatographic method has been developed for the first time to simultaneously determine the eight major biologically active ingredients, namely paeoniflorin, naringin, sennoside A, baicalin, baicalein, saikosaponin a, rhein and emodin of the Chinese herbal formula Da-Chai-Hu-Tang. The contents of these marker substances in Da-Chai-Hu-Tang extract could be easily determined within 85 min. The assay was reproducible and accurate with overall intra-day variations and accuracy of less than 2% and more than 97.9%, respectively. Results indicate that the developed HPLC assay can be successfully utilized as a quality control method for simultaneous determination of eight representative substances in Da-Chai-Hu-Tang.  相似文献   
68.
Early stage diabetic nephropathy is characterized by elevated glomerular filtration. Recent studies have identified high-glucose induced p38 MAPK (p38) over-activation in mesangial cells. Mesangial hypocontractility is the major underlying mechanism, however, no ameliorating agents are currently available. We investigated the protective effects of emodin on high-glucose induced mesangial cell hypocontractility. Mesangial cells were cultured under normal (5.6 mM) and high glucose (30 mM) conditions. Emodin was administrated at doses of 50 mg/l and 100 mg/l. Angiotension II stimulated cell surface reductions were measured to evaluate cell contractility. p38 activity was detected using Western blotting. To further explore the possible mechanism of emodin, expression of the peroxisome proliferator-activated receptor γ (PPARγ) was measured and its specific inhibitor, gw9662, was administrated. Our results showed: (1) high-glucose resulted in a 280% increase in p38 activity associated with significant impairment of mesangial contractility; (2) emodin treatment dose-dependently inhibited high-glucose induced p38 over-activation (a 40% decrease for 50 mg/l emodin and a 73% decrease for 100 mg/l emodin), and mesangial hypocontractility was ameriolated by emodin; (3) both the PPARγ mRNA and protein levels were elevated after emodin treatment; (4) inhibition of PPARγ using gw9662 effectively blocked the ameliorating effects of emodin on high-glucose induced p38 over-activation and mesangial hypocontractility. Emodin effectively ameliorated p38 over-activation and hypocontractility in high-glucose induced mesangial cells, possibly via activation of PPARγ.  相似文献   
69.
建立了高效液相色谱法(HPLC)同时测定首乌益智胶囊中大黄素和大黄素甲醚含量的方法。采用C18(250 mm×4.6 mm,5 μm)色谱柱,以甲醇 0.1%磷酸水(82:18,V/V)为流动相,检测波长为289 nm,流速为1.0 mL/min,柱温30 ℃。测得大黄素在0.019~0.19 μg(R=0.999 9,n=5)、大黄素甲醚在0.021~0.21 μg(R=1.000 0,n=5)线性关系良好;大黄素和大黄素甲醚的平均回收率分别为98.58%、100.01%,相对标准偏差分别为2.66%、1.15%。研究表明,该方法专属性强、结果准确,可作为同时测定首乌益智胶囊中大黄素和大黄素甲醚含量的方法。  相似文献   
70.
The micronization of emodin in a mixed solution of dichloromethane and methanol by the Solution Enhanced Dispersion by Supercritical Fluids through Prefilming Atomization (SEDS‐PA) process has been successfully performed. Morphologies and particle sizes (PSs) of the emodin microparticles were analyzed by scanning electron microscopy. The results of micronization show that the acicular or rod‐like emodin crystals with PSs of about 3‐10 µm wide and 100‐300 µm long have successfully been micronized to needle‐like, rod‐like, twisted fiber‐like and coalesced net‐like microparticles with PSs of about 0.1‐1.0μm wide and 2‐40μm long by the SEDS‐PA process. The effect of technological conditions on micronization has been studied. With the increase of initial solution concentration and temperature, the PSs of emodin microparticles increase. With the increase of solution flow rate and pressure, the PSs of emodin microparticles decrease. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
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