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1.
目的 对比研究朝鲜淫羊藿酸性多糖酯化还原前后的理化特性,并探讨其改善油酸诱导的肝癌HepG2细胞脂质堆积活性的差异。方法 采用高效凝胶渗透色谱法测定朝鲜淫羊藿酸性多糖(EFPA)的均一性和分子量,高效液相色谱法测定EFPA和酯化还原后朝鲜淫羊藿酸性多糖(EFPA-R)的单糖组成;采用油酸(OA)处理HepG2细胞诱导建立脂质蓄积模型,不同浓度EFPA与EFPA-R(10、30、100、300 μg·mL-1)分别和OA共同作用于细胞24 h,采用CCK-8试剂盒测定细胞存活率,油红O染色观察细胞内脂滴蓄积情况,并采用试剂盒测定细胞内总胆固醇(TC)、甘油三酯(TG)含量。结果 EFPA为成分均一的多糖组分,分子量为125.8 kDa,由甘露糖、葡萄糖、半乳糖、葡萄糖醛酸和阿拉伯糖组成,摩尔比为1.7∶7.4∶1.4∶1.8∶1.0,葡萄糖占比最大,EFPA-R由甘露糖、葡萄糖、半乳糖和阿拉伯糖组成,摩尔比为0.8∶10.6∶2.1∶1.0;在10-300 μg·mL-1范围内,EFPA和EFPA-R对HepG2细胞的抑制作用较弱,作为给药浓度;与空白组相比,模型组细胞中TC、TG含量显著升高(P < 0.01),细胞内红色脂滴显著增多,与模型组相比,EFPA可显著降低细胞中TC、TG含量(P < 0.01),明显减少细胞内红色脂滴(P < 0.05或P < 0.01),EFPA-R干预后细胞则无明显变化。结论 EFPA可明显改善HepG2细胞脂质堆积情况,且呈现剂量依赖性,而半乳糖醛酸(GalA)的存在可能是其抑制HepG2细胞脂质蓄积的关键因素。 相似文献
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5.
Effects of the Clearing the Lung and Dissipating Phlegm Method in the Treatment of Acute Exacerbation of Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-Analysis 下载免费PDF全文
Tao Zhang Yao-Hui Li Gai-Xia Liu Xiu-Lin Tang 《World Journal of Traditional Chinese Medicine》2019,(1)
Objective: The objective of this study is to evaluate the efficacy and safety of the clearing the lung and dissipating phlegm method in the treatment of acute exacerbation of chronic obstructive pulmonary disease(COPD) and to provide evidence for the treatment of the disease. Materials and Methods: Literature was searched from the United States National Library of Medicine(PubMed), Embase, Cochrane Library, China National Knowledge Infrastructure, Wanfang Database(Wanfang), and the Full?Text Database of Chinese Scientific and Technical Periodicals(VIP).A comprehensive collection was made of randomized controlled trials(RCTs) before June 2018, in which the treatment groups used either the clearing the lung and dissipating phlegm formulas only or combined it with routine Western medicine therapy, and the control group adopted routine Western medicine therapy only for the acute exacerbation of COPD. The Cochrane risk of bias method was used to evaluate the quality of the literature. The data were analyzed and retrieved independently by two reviewers before meta?analysis was carried out with RevMan 5.3 software to evaluate the primary outcome measures, including the total clinical effective rate, and the secondary outcome measures such as the pulmonary function(forced vital capacity [FVC], forced expiratory volume in the 1 s [FEV1], percentage of FEV1 [FEV1%], and FEV1/FVC)and blood gases(PaO_2 and PaCo_2). Results: A total of 13 RCTs involving 990 patients(496 in the treatment group and 494 in the control group)were included in this study. Meta?analysis revealed significant difference in the efficacy of the group that adopted solely the routine Western medicine method and the group that combined the Western medicine with the clearing the lung and dissipating phlegm method. Outcome measures including the pulmonary function(FVC, FEV1, FEV1%, and FEV1/FVC) and the blood gases(PaO_2 and PaCo_2) were significantly improved as compared to the control group(P 0.00001). However, adverse effects in the treatment group using combined traditional Chinese medicine were not reported due to the short observation time of the study. Conclusion: The clearing the lung and dissipating phlegm method can improve the efficacy in the treatment of acute exacerbation of COPD, the outcome measures of the pulmonary function and the blood gases,as well as the life quality of the patients. However, due to the fact that the existing studies are generally of poor quality in which randomization and its implementation were not properly carried out, more high?quality RCTs are necessary to confirm the findings of this study. 相似文献
6.
Simultaneous Determination of Six Compounds in Rat Plasma by Ultra‑Performance Liquid Chromatography with Tandem Mass Spectrometry: Application in the Pharmacokinetic Study of Qing Gan‑Shu Yu‑Fang 下载免费PDF全文
Hai Jiang A‑Jiao Hou Yan‑Yan Zhang Wen‑Jing Man Liu Yang Yong‑Hai Meng Xin‑Yue Guo Song Wang Jia‑Xu Zhang Bing‑You Yang Qiu‑Hong Wang Kelvin Chan Hai‑Xue Kuang 《World Journal of Traditional Chinese Medicine》2019,(4)
A rapid and high selective ultra?performance liquid chromatography (UPLC) with tandem mass spectrometry method for simultaneous
determination of six compounds including albiflorin, paeoniflorin, picroside I, picroside II, saikosaponin A, and saikosaponin D in rat plasma
was developed and validated using butyl p-hydroxybenzoate as an internal standard. One-step direct protein precipitation with acetonitrile was
used to extract the compounds from the rat plasma samples. Chromatographic separation was achieved using an ACQUITY UPLC BEH C18
column (100 mm × 2.1 mm, 1.7 µm) at a flow rate of 0.4 mL/min, using gradient mode containing 0.1% formic acid in water and acetonitrile
were used as the Mobile phase A and B. Electrospray ionization in negative ion mode and multiple reaction monitoring were used to identify
and quantify active components. Calibration curves showed good linearity (R2 > 0.9908) over a wide concentration range for all compounds.
The intra- and interday precision (relative standard deviation) ranged 2.4%–7.0% and 2.6%–8.0%, respectively. The accuracy (relative error)
was from ?13.0% to 13.2% at all quality control levels. The recovery ranged from 81.1% to 92.5%. The validated method was successfully
applied to pharmacokinetic study in rats after oral administration of Qing Gan?Shu Yu?Fang. The results show that one can draw a conclusion
that these six active ingredients can be quickly absorbed and play a pharmacodynamic role rapidly in vivo. 相似文献
7.
正目前,临床上对于直肠癌常用的影像评估方法有MRI、螺旋CT、PET-CT、直肠腔内超声(ERUS)等。而MRI作为首选检查方式,对肿瘤位置、浸润深度、淋巴结转移、血管侵犯、环周切缘及周围器官侵犯等方面的评估均具有明显优势~([1-2])。通过MRI诊断淋巴结的方法通常是影像科医师逐层浏览每一幅图像,从中识别淋巴结的形状、界限及密度来判断,这种传统方式耗时较长且存在主观偏倚,导致 相似文献
9.