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1.
In the present study, we aimed to observe the effects of ethanol extract of Oxalis corniculata L. on bleeding time (BT) and coagulation time (CT) and determine its acute toxicity in mice. Firstly, the ethanol extract of O. corniculata was administered to 40 mice, which were randomly divided into the normal control group, Yunnan Baiyao control group, low-dose group, and high-dose group. The low-dose (0.6 g/kg) and high-dose (1.2 g/kg) groups received ethanol extract of O. corniculata by gavage, and the BT and CT of the mice were measured by the slide method and tail clipping method, respectively. Secondly, the median lethal dose method was used with 50 mice to observe the physiological state, poisoning reaction, and death of the mice after intragastric administration. Finally, on the 14th day of the experiment, a necropsy was performed to observe any abnormality of the organs. In conclusion, in the coagulation and hemostasis tests, there were no statistical differences between the groups (P > 0.05), while there was a significant dose-response relationship, and the BT and CT were significantly shorter than those of the negative control group, which were comparable to the Yunnan Baiyao control group. Moreover, in the acute toxicity test, the median lethal dose of ethanol extract of O. corniculata was 6.0291 g/kg, with a 95% confidence interval of 5.3065–6.7829 mg/kg.  相似文献   
2.
目的:考察黑豆汁炖制时间对制何首乌外观性状及各类有效成分含量变化规律的影响。方法:采用HPLC同时测定不同炮制时间制何首乌样品中二苯乙烯苷、大黄素、大黄素甲醚、大黄素-8-O-β-D-葡萄糖苷、大黄素甲醚-8-O-葡萄糖苷的含量,选择Agilent ZORBAX Extend-C_(18)色谱柱(4. 6 mm×250 mm,5μm),甲醇(A)-水(B)为流动相梯度洗脱(0~30 min,5%~100%A; 30~40 min,100%A),流速1. 0 mL·min~(-1),柱温35℃,检测波长280 nm。结果:随炖制时间的增加,二苯乙烯苷含量逐渐降低,与8 h时相比,至64 h时含量降低76%;大黄素-8-O-β-D-葡萄糖苷和大黄素甲醚-8-O-葡萄糖苷2种蒽醌苷含量先上升后下降,至24 h时达最高值,炖制40 h时降至与8 h近似的水平,之后略有波动;大黄素、大黄素甲醚2种蒽醌苷元含量先上升后下降,炖制32 h时达最大值,之后缓慢降低并趋于稳定。结论:炖制时间对制何首乌中各类成分含量的影响显著,且变化趋势不尽相同,应规范制何首乌饮片的炮制时间;同时,仅以二苯乙烯苷及蒽醌类成分作为制何首乌的指标性成分依据不够充分,应考虑增加多糖类等质量控制指标。  相似文献   
3.
目的:为了解决白芷生产过程中盲目引种、生产无序等导致的药材品质不达标、农残超标等问题,对白芷无公害规范化种植技术进行探讨。方法:利用药用植物全球产地生态适宜性区划信息系统(GMPGIS)Ⅱ对白芷栽培选地进行科学预测,得出潜在的白芷和川白芷各自生态适宜区。同时,根据白芷种质资源现状、产区考察、文献研究,建立一套无公害白芷规范化种植技术体系。结果:白芷引种栽培以黑龙江、河北、内蒙古、山西、河南一带为宜;川白芷引种栽培以湖南、江西、四川、浙江、贵州一带为宜。建立了一套从选地整地、播种、间苗定苗、施肥、田间管理、病虫害防治、采收储存、良种繁育的完整无公害白芷规范化种植体系。结论:白芷无公害规范化种植技术体系的建立为白芷无公害精细栽培奠定基础,也为现阶段中药材种植产业精细、集约、高产、高品质的种植发展方向提供参考。  相似文献   
4.
Macrophages are the most abundant immune cells in the lung, which play an important role in COPD. The anti-inflammatory and anti-oxidation of ergosterol are well documented. However, the effect of ergosterol on macrophage polarization has not been studied. The objective of this work was to investigate the effect of ergosterol on macrophage polarization in CSE-induced RAW264.7 cells and Sprague-Dawley (SD) rats COPD model. Our results demonstrate that CSE-induced macrophages tend to the M1 polarization via increasing ROS, IL-6 and TNF-α, as well as increasing MMP-9 to destroy the lung construction in both RAW264.7 cells and SD rats. However, treatment of RAW264.7 cells and SD rats with ergosterol inhibited CSE-induced inflammatory by decreasing ROS, IL-6 and TNF-α, and increasing IL-10 and TGF-β, shuffling the dynamic polarization of macrophages from M1 to M2 both in vitro and in vivo. Ergosterol also decreased the expression of M1 marker CD40, while increased that of M2 marker CD163. Moreover, ergosterol improved the lung characters in rats by decreasing MMP-9. Furthermore, ergosterol elevated HDAC3 activation and suppressed P300/CBP and PCAF activation as well as acetyl NF-κB/p65 and IKKβ, demonstrating that HDAC3 deacetylation was involved in the effect of ergosterol on macrophage polarization. These results also provide a proof in immunoregulation of ergosterol for therapeutic effects of cultured C. sinensis on COPD patients.  相似文献   
5.
目的研究人参、白术有效组分群对慢性萎缩性胃炎大鼠口腔、肠道菌群的影响。方法将大鼠随机分为空白组、模型组、给药(人参白术有效组分群)组,用主动免疫法复制慢性萎缩性胃炎模型。HE染色、扫描电子显微技术观察胃黏膜组织显微及超微结构,高通量测序技术检测肠道及口腔菌群,利用SPSS软件进行相关性分析。结果人参、白术有效组分群能改善慢性萎缩性胃炎大鼠胃组织病理形态(P<0.05);增加大鼠肠道、口腔菌群多样性及丰富度(P<0.05);减少肠道、口腔中致病菌群(普雷沃氏菌科_UCG-003、梭杆菌属)的数目(P<0.05)。其中,大鼠病理学评分与其口腔、肠道菌群的丰度、多样性以及门、属水平上的差异菌具有相关性(P<0.05)。结论人参、白术有效组分群对慢性萎缩性胃炎大鼠有良好的保护作用,缓解胃黏膜萎缩,其作用机制可能与改善肠道和口腔菌群有关。  相似文献   
6.
The aim of this systematic review and meta‐analysis was to analyze the effects of grape seed extract (GSE) on glycemic control and serum lipoproteins, inflammation and body weight. Two independent authors systematically searched online databases including EMBASE, Scopus, PubMed, Cochrane Library, and Web of Science from inception until May 30, 2019. Cochrane Collaboration risk of bias tool was applied to assess the methodological quality of included trials. The heterogeneity among the included studies was assessed using Cochrane's Q test and I‐square (I2) statistic. Data were pooled using a random‐effects model and weighted mean difference (WMD) was considered as the overall effect size. Fifty trials were included in this meta‐analysis. Pooling effect sizes from studies demonstrated a significant decrease in fasting plasma glucose (FPG) (WMD): ?2.01; 95% confidence interval (CI): ?3.14, ?0.86), total cholesterol (TC; WMD: ?6.03; 95% CI: ?9.71, ?2.35), low‐density lipoprotein (LDL) cholesterol (WMD: ?4.97; 95% CI: ?8.37, ?1.57), triglycerides (WMD: ?6.55; 95% CI: ?9.28, ?3.83), and C‐reactive protein (CRP) concentrations (WMD: ?0.81; 95% CI: ?1.25, ?0.38) following GSE therapy. Grape seed did not influence HbA1c, HDL cholesterol levels, and anthropometric measurements. This meta‐analysis demonstrated that GSE intake significantly reduced FPG, TC, LDL cholesterol, triglycerides, and CRP levels.  相似文献   
7.
黄芪始载于《神农本草经》,有补气升阳、益卫固表,利水消肿,托毒生肌之效。被誉为补气健脾之要药,临床上常用于气虚乏力、脾虚泄泻等疾病,已为医者所熟知。近年来,研究学者围绕其补气、健脾、利水功效机制已有较全面的认识。然陶弘景在《本草经集注》首载黄芪"逐五脏间恶血",表明本品兼有活血作用。目前,对于本品活血作用机制阐释,中医常基于"补气活血""气行血行"理论进行论证,但并不等同于本品无活血作用。通过梳理历代本草文献中对黄芪的记载,发现其活血作用应用广泛。综合传统方剂与现代方剂中有关其活血作用的应用,本品在方中行活血通络、活血利水、活血扶正作用,尤能体现其活血作用。且现代药理学研究在有关瘀血病理指标的分子机制中,黄芪有很好的调控作用,表明黄芪有活血作用,但未深入探究,存在研究价值。该文从历代文献对黄芪活血功效的论述、黄芪活血作用的临床应用及现代药理学研究深入探讨其活血作用机制,以期扩展黄芪的临床应用范围,为临床治疗提供理论指导。  相似文献   
8.
目的:建立地黄不同炮制品的薄层色谱鉴别方法。方法:以D-果糖、梓醇、蔗糖、棉子糖、水苏糖、蜜二糖及甘露三糖为对照品,考察提取溶剂(水,20%甲醇,50%甲醇,80%甲醇),展开剂(正丁醇-甲醇-三氯甲烷-冰乙酸-水,乙酸乙酯-吡啶-冰乙酸-水,正丁醇-冰乙酸-水),显色剂(苯胺-二苯胺-磷酸溶液,茚三酮溶液),点样量(2,4,6μL),检视条件(日光,日光底部灯,365 nm和254 nm)对薄层色谱分析的影响,确定生地黄及熟地黄饮片的供试品溶液制备方法和最佳薄层色谱条件。结果:采用薄层色谱高效硅胶G板,以正丁醇-甲醇-三氯甲烷-冰乙酸-水(13∶5∶5∶1∶2)为展开剂展开,喷以苯胺-二苯胺-磷酸溶液,110℃下加热显色,于日光底部灯下进行检视,所得地黄不同炮制品薄层色谱分离效果和显色效果较佳,斑点清晰且特征性好。结论:该薄层色谱鉴别方法操作简便易行,定性特征明显、结果直观,可有效鉴别地黄不同炮制品,并可为熟地黄的炮制终点确定提供实验依据。  相似文献   
9.
Croton stellatopilosus (Plaunoi) leaves accumulate several diterpenes and possess various pharmacological activities. The present study aimed to prepare, characterize and assess the antibacterial activity of inclusion complexes prepared by mixing plaunotol (PL) or plaunoi extract (PE) with cyclodextrins (CD), including α-CD, β-CD, γ-CD, and hydroxypropyl-β-cyclodextrin (HP-β-CD). The inclusion complexes were characterized using SEM, XRD, DSC, and FT-IR and evaluated for aqueous solubility and thermal stability. The PL and PE lyophilized complexes with HP-β-CD were further evaluated for their antibacterial activity against acne-causing bacteria. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of PL, PE, and the inclusion complexes evaluated using the agar dilution method revealed that the MIC and MBC values of the inclusion complexes were lower than those of PL or PE alone. Interestingly, the complexes had a synergistic activity with clindamycin after testing with checkerboard assay. The hydrogel containing the inclusion complex and clindamycin were assessed for antibacterial activity using the agar well diffusion method. The results indicated that the hydrogels showed significant inhibition of bacterial growth. In conclusion, the prepared solid dispersion of PL or PE with HP-β-CD could enhance antibacterial activity by increasing the drug solubility. The hydrogels containing PL or PE complex and clindamycin could be considered as a candidate for the treatment of acne vulgaris.  相似文献   
10.
目的 基于网络药理学和分子对接技术探究黄芪-赤芍配伍对治疗慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)的作用机制。方法 利用TCMSP,Pharmmaper数据库,筛选黄芪-赤芍治疗COPD的活性成分和潜在靶点;结合Genecards数据库挖掘的COPD相关靶点,对黄芪-赤芍药对与COPD靶点进行PPI网络构建,交互处理得到黄芪-赤芍药对治疗COPD的关键靶点,并进行GO分析和KEGG通路富集分析;并采用分子对接技术将主要活性成分与TNF-α(肿瘤坏死因子),IL-6(白细胞介素6)等进行分子对接;最后利用A549炎症细胞与人脐静脉内皮细胞缺氧损伤模型进行体外细胞实验对结果加以验证。结果 黄芪-赤芍药对中44个有效成分作用于COPD,核心成分为:槲皮素、山奈酚、丁子香萜、芍药苷、(2R,3R)-4-methoxyl-distylin、二氢异黄酮;黄芪-赤芍药对通过IL6、PTGS2、TNF等113个靶蛋白,调控Ras、PI3KAkt、IL-17等多条信号通路治疗COPD,且分子对接结果显示槲皮素、山奈酚、丁子香萜、芍药苷与IL-6、PTGS2、TNF大分子蛋白有良好的结合性,体外细胞试验证实,槲皮素与山奈酚均能减少IL-8,MMP-9炎症因子的分泌,具有不同程度的抗炎效果;芍药苷有明显的扩血管、抗血栓之效。结论 黄芪-赤芍药对治疗COPD具有多成分、多靶点、多通路、整体调节的作用特点。初步揭示了黄芪-赤芍药对通过抑制炎症反应、调节上皮细胞生长增强保护屏障等预测出黄芪-赤芍药对治疗COPD的潜在作用机制,以期为其活性成分的药效物质基础提供理论研究和思路。  相似文献   
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