排序方式: 共有149条查询结果,搜索用时 15 毫秒
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源于中药选择性效应的新型免疫抑制疗法 总被引:3,自引:0,他引:3
近年来免疫学的发展日新月异,但与其他系统药物相比,免疫系统药物的发展十分落后。低选择性是现有免疫抑制剂的重要缺陷,这使得需要长期用药的自身免疫性疾病常因药物的严重副作用而使治疗无法持续。因此,免疫系统药物的研制必须另辟蹊径。本文在阐述免疫抑制剂发展现状的基础上,通过本课题组关于中药及其成分的研究结果,提出了选择性抑制活化T细胞的免疫抑制新模式,从作用特点、作用机理、代谢产物以及与现有免疫抑制剂的比较等角度论证了选择性免疫抑制的可行性,从而为免疫性疾病的治疗以及新型免疫抑制剂的研制提供新的思路。 相似文献
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溶剂浮选法分离富集大黄中的有效成分 总被引:1,自引:0,他引:1
采用溶剂浮选法对大黄提取液中的芦荟大黄素、大黄素、大黄酚以及大黄素甲醚进行了分离富集,并用高效液相色谱法分别测定了其含量。考察了料液浓度、浮选溶剂、浮选时间、浮选液pH值、氮气流速和电解质NaCl浓度对浮选效率的影响,并与泡沫浮选法和溶剂萃取法进行了比较。结果表明:溶剂萃取效果最差,泡沫浮选次之,溶剂浮选法分离富集效果最好。当料液浓度为6.4mg/mL,浮选时间为30min,浮选液pH一1~2,氮气流速为20mL/min,电解质NaCl浓度为0.4mol/L时,溶剂浮选效率最佳。 相似文献
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建立泽泻中三萜类成分的最佳提取工艺,并考察其对老年性耳聋小鼠血清生理学指标的影响。通过正交试验优化泽泻三萜类成分的提取工艺,并用紫外分光光度法(UV)测定含量。采用D-半乳糖建立小鼠老年性耳聋模型,灌胃给予泽泻三萜类成分提取物后,测定小鼠血清丙二醛(MDA)含量和超氧化物歧化酶(SOD)活力。结果表明:泽泻三萜类成分的最佳提取工艺为:料液比1∶8,85%乙醇超声提取60 min,重复提取2次。通过D101大孔吸附树脂纯化后,泽泻三萜类成分的平均含量为4.55%。给药后,样品组小鼠血清SOD值较模型组明显升高,但MDA值变化不明显。所建立的最佳提取工艺具有较好的收率、稳定性以及可行性。 相似文献
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Dong Zhang Mojiao Zhao Yumei Li Dafang Zhang Yong Yang Lijing Li 《Molecules (Basel, Switzerland)》2021,26(23)
Xanthine oxidase (XOD) inhibition has long been considered an effective anti-hyperuricemia strategy. To identify effective natural XOD inhibitors with little side effects, we performed a XOD inhibitory assay-coupled isolation of compounds from Smilacis Glabrae Rhizoma (SGR), a traditional Chinese medicine frequently prescribed as anti-hyperuricemia agent for centuries. Through the in vitro XOD inhibitory assay, we obtained a novel XOD inhibitor, 5-O-caffeoylshikimic acid (#1, 5OCSA) with IC50 of 13.96 μM, as well as two known XOD inhibitors, quercetin (#3) and astilbin (#6). Meanwhile, we performed in silico molecular docking and found 5OCSA could interact with the active sites of XOD (PDB ID: 3NVY) with a binding energy of −8.6 kcal/mol, suggesting 5OCSA inhibits XOD by binding with its active site. To evaluate the in vivo effects on XOD, we generated a hyperuricemia mice model by intraperitoneal injection of potassium oxonate (300 mg/kg) and oral gavage of hypoxanthine (500 mg/kg) for 7 days. 5OCSA could inhibit both hepatic and serum XOD in vivo, together with an improvement of histological and multiple serological parameters in kidney injury and HUA. Collectively, our results suggested that 5OCSA may be developed into a safe and effective XOD inhibitor based on in vitro, in silico and in vivo evidence. 相似文献
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In vitro and in vivo identification of metabolites of magnoflorine by LC LTQ‐Orbitrap MS and its potential pharmacokinetic interaction in Coptidis Rhizoma decoction in rat 下载免费PDF全文
Baojuan Xue Yuanyuan Zhao Qing Miao Peipei Miao Xiaoyan Yang Guixia Sun Jin Su Jing Ye Baohong Wei Yuanyuan Zhang Yujie Zhang 《Biomedical chromatography : BMC》2015,29(8):1235-1248
Magnoflorine, an important aporphine alkaloid in Coptidis Rhizoma, is increasingly attracting research attention because of its pharmacological activities. The in vivo and in vitro metabolism of magnoflorine was investigated by LC LTQ‐Orbitrap MS. In vivo samples including rat urine, feces, plasma and bile were collected separately after both oral (50 mg kg?1) and intravenous administration (10 mg kg?1) of magnoflorine, along with in vitro samples prepared by incubating magnoflorine with rat intestinal flora and liver microsome. As a result, 12 metabolites were found in biological samples. Phase I metabolites were identified in all biological samples, while phase II metabolites were mainly detected in urine, plasma and bile. In a pharmacokinetic study, rats were not only dosed with magnoflorine via oral (15, 30 and 60 mg kg?1) and intravenous administration (10 mg kg?1) but also dosed with Coptidis Rhizoma decoction (equivalent to 30 mg kg?1 of magnoflorine) by intragastric administration to investigate the interaction of magnoflorine with the rest of compounds in Coptidis Rhizoma. Studies showed that magnoflorine possessed lower bioavailability and faster absorption and elimination. However, pharmacokinetic parameters altered significantly (p < 0.05) when magnoflorine was administered in Coptidis Rhizoma decoction. Oral gavage of Coptidis Rhizoma decoction decreased the absorption and elimination rates of magnoflorine, which revealed that there existed pharmacokinetic interactions between magnoflorine and the rest of ingredients in Coptidis Rhizoma. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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苦黄注射液中大黄蒽醌含量测定方法改进 总被引:2,自引:0,他引:2
按苦黄注射液原质量标准(草案)中测定方法,大黄蒽醌用氯仿提取,阴性试验结果为苦黄注射液大黄蒽酯标示量的16.50%(n=5),结果偏高;改用石油醚提取,降为6.15%,重复性试验的RSD为1.44%(n=5),加标回收率为101.8%(n=5),显色在1-4h内稳定,表明该法是可行的。 相似文献
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Structural elucidation and identification of alkaloids in Rhizoma Coptidis by electrospray ionization tandem mass spectrometry 总被引:2,自引:0,他引:2
Simple, convenient, sensitive and accurate analytical methods are needed for the structural characterization and identification of alkaloid components in Rhizoma Coptidis in traditional Chinese herbal medicine, which has important bioactivity. In this work, the identification of alkaloid compounds in Rhizoma Coptidis was investigated by obtaining molecular mass information using electrospray ionization mass spectrometry (ESI-MS). Multi-stage tandem mass spectrometric (ESI-MS(n)) data for the alkaloid compounds were used for detailed structural characterization, then structure information was obtained by comparison of the fragmentation mechanisms of both alkaloids in Rhizoma Coptidis and standard samples of berberine, palmatine, coptisine and jatrorrhizine by MS. Based on the results obtained, the structure of a novel compound was elucidated. The results of the experiments demonstrate that ESI-MS(n) is a sensitive, selective and effective tool for the rapid determination of alkaloids in Rhizoma Coptidis. 相似文献
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Orthogonal separation protocol for the simultaneous preparation of four medically active compounds from Anemarrhenae Rhizoma by sequential polyamide and macroporous resin adsorbent chromatography 下载免费PDF全文
Sihui Nian Ehu Liu Yong Fan Raphael N. Alolga Ping Li 《Journal of separation science》2016,39(16):3195-3204
The green and efficient preparation of natural products from biomass is considered an important area of interest in pharmaceutical applications. In this study, we aimed to provide a practical example with a popular traditional Chinese medicine, Anemarrhenae Rhizome, and showcase the orthogonal use of column chromatography with polyamide and macroporous adsorption resins to selectively concentrate and efficiently purify four bioactive compounds: neomangiferin (NMF), mangiferin (MF), timosaponin B‐II (TS B‐II), and timosaponin A‐III (TS A‐III). First, polyamide T60–100 was employed to fractionalize the crude extracts of Anemarrhenae Rhizome. Macroporous resin HPD400 was subsequently used to purify the xanthones and steroidal saponins. Under the optimized conditions, 2.31 g of NMF, 4.10 g of MF, 12.87 g of TS B‐II, and 2.78 g of TS A‐III were prepared from 1 kg of crude materials, and their purities were 90.0, 92.15, 90.8, and 92.61%, respectively. The results of this study indicate that the combined column chromatography with polyamide and macroporous adsorption resins can be referenced as a green and efficient alternative for large‐scale purification of bioactive ingredients from herbal raw materials. 相似文献