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991.
将109例高血压病患者随机分为两组,中药组用90大圣降压口服液,对照组用硝苯吡啶。结果:中药组临床有效率下降压作用与对照组比较均无显著性差异(P均>0.05);但中药组在改善微循环、降低动脉硬化指数方面有效,且在降低血脂、提高高密度脂蛋白(HDL)方面,明显优于对照组(P<0.05)。实验研究表明:中药组能有效地降低易卒中自发性高血压大白鼠(SHRS)的血压,提高小鼠耐缺氧的能力。临床和毒理试验均 相似文献
992.
黄褐毛忍冬和灰毡毛忍冬几种成分对大、小鼠化学性肝损伤的保护作用 总被引:2,自引:0,他引:2
目的:研究黄褐毛忍冬和灰毡毛忍冬几种成分对四氯化碳(CCl4),D-氨基半乳糖(D-Gal)等肝毒物造成大、小鼠肝损伤的保护作用。方法:大、小鼠分别sc黄褐毛忍冬和灰毡毛忍冬几种成分后,ipCCl4或D-Gal,检测血清谷丙转氨酶(sGPT)、肝脏甘油三酯(TG)和丙二醛(MDA)含量。结果:黄褐毛忍冬和灰毡毛忍冬几种成分均不同程度的降低由CCl4和D-Gal引起的sGPT和TG的升高,降低CCl4引起的MDA升高。结论:黄褐毛忍冬和灰毡毛忍冬几种成分具有降低几种肝毒物引起的肝脏毒性的作用。 相似文献
993.
反复心理应激大鼠血浆和下丘脑单胺神经递质的变化及加味四逆散的影响 总被引:13,自引:0,他引:13
目的 :观察反复心理应激大鼠血浆和下丘脑内DA、5 HT、E、NE的变化以及加味四逆散的影响。方法 :采用限制大鼠活动空间的方法造成反复心理应激的动物模型 ;血浆和下丘脑内DA、5 HT、E、NE含量测定采用电化学高效液相色谱分析方法。结果 :反复心理应激大鼠血浆DA、5 HT含量明显降低 ,NE、E含量则明显升高 ,下丘脑DA和 5 HT含量明显降低。加味四逆散可以升高应激大鼠下丘脑和血浆中DA、5 HT含量 ,并能降低血浆中NE、E含量 ,升高下丘脑和血浆 5 HT/NE以及血浆 5 HT/E ,作用优于人参总皂甙。结论 :加味四逆散可显著增强反复心理应激状态大鼠的抗应激能力 ,其机制与其升高中枢和血浆中 5 HT及DA含量 ,降低血浆中NE和E含量有关。 相似文献
994.
Wang X Zhang F Liu Z Feng H Yu ZB Lu Y Zhai H Bai F Shi Y Lan M Jin J Fan D 《Journal of ethnopharmacology》2008,117(1):102-107
AIM OF THE STUDY: Croton tiglium (Croton tiglium L., Euphorbiaceae) is widely used as a herb for treatment of gastrointestinal disturbances. Previous studies established its purgative and inflammational properties. The present study aimed to investigate the effects of Croton tiglium oil (CO) on intestinal transit in mice. MATERIALS AND METHODS: Gastrointestinal transit in mice and contractile characteristics of isolated intestinal strips from mice were evaluated. Intestinal inflammation was confirmed by histological examination. RESULTS: Low dose of CO increased the gastrointestinal transit of charcoal and barium meal as well as the production of fecal pellets in mice. In contrast, high dose exerted inhibitory effects. For normal colonic circular strips, both high and low dose of CO inhibited the contractile frequency. Low doses (0-20 microg/ml) of CO enhanced the phasic contractions, while high doses (>40 microg/ml) reduced them. Colonic longitudinal strips in CO-treated mice were less sensitive to electrical field stimulation than those in control mice. The contraction of colonic longitudinal, colonic and jejunal circular strips in CO-treated mice was more sensitive to atropine than that in control mice. CONCLUSIONS: CO might modulate gastrointestinal motility and induce intestinal inflammation related to immunological milieu and motor activity. Our findings may highlight the ethno-medical uses of Croton tiglium on intestinal disorders. 相似文献
995.
Xi Huang Hang Yu Cong Xie Yao-Long Zhou Meng-Meng Chen Han-Lin Shi Wei-Feng Tang Jing-Cheng Dong Qing-Li Luo 《Pharmaceutical biology》2022,60(1):1520
ContextAsthma is a common respiratory system disease. Louki Zupa decoction (LKZP), a traditional Chinese medicine, presents a promising efficacy against lung diseases.ObjectiveTo investigate the pathogenic mechanism of asthma and reveal the intervention mechanism of LKZP.Materials and methodsForty-eight female Balb/c mice were randomly divided into 6 groups: normal control group (NC), ovalbumin (OVA)/saline asthma model group, OVA/LL group, OVA/LM group, OVA/LH group and OVA/DEX group (n = 8 per group). The asthmatic mice were modelled through intraperitoneal injecting and neutralizing OVA. LKZP decoction was administrated by gavage at the challenge stage for seven consecutive days (2.1, 4.2 and 8.4 g/kg/day). We investigated the change in lung function, airway inflammation, mucus secretion and TH-1/TH-2-related cytokines. We further verify the activated status of the IL-33/ST2/NF-κB/GSK3β/mTOR signalling pathway.ResultsLKZP was proved to improve asthmatic symptoms, as evidenced by the down-regulated airway resistance by 36%, 58% and 53% (p < 0.01, p < 0.001 vs. OVA/saline group), up-regulated lung compliance by 102%, 114% and 111%, decreased airway inflammation and mucus secretion by 33%, 40% and 33% (p < 0.001 vs. OVA/saline group). Moreover, the content of cytokines in BALF related to airway allergy (such as IgE) and T helper 1/T helper 2 cells (like IL-2, IL-4, IL-5, IL-13, TNF-α and IFN-γ), were also markedly reduced by 13–65% on LKZP intervention groups compared with model group. Mechanistic research revealed that the IL-33/ST2-NF-κB/GSK3β/mTOR signalling pathway was activated in the OVA/saline group and LKZP significantly down-regulated this pathway.Discussion and conclusionLKZP improves lung function, airway inflammation, mucus secretion and correct immune imbalance by intervening with the IL-33/ST2-NF-κB/GSK3β/mTOR signalling pathway, presenting a promising therapeutic choice for asthma. 相似文献
996.
The current work focuses on the DFT calculation of the rational mechanism and catalytic activity of the gold(i)-catalyzed isotetradehydro-Diels–Alder cycloaddition of cyanamides and enamides to substituted 2,6-diaminopyridines. IPrAuCl is used as a model catalyst to catalyze cyanamide and enynamide reactants with different substituents in DCM as a research system. DFT data indicates that the catalytic cycle starts from the triple bond coordination between the catalyst''s gold cation and the enamide to obtain the gold π-complex, and the cyanamide attacks the alkynyl carbon atom from different directions to generate two reaction channels of five-membered and six-membered heterocycles, respectively. The calculation results show that the 2,6-diaminopyridine compounds produced by this catalytic reaction have lower activation energy and higher reactivity, that is, the pyridine skeleton structure can be easily obtained under mild reaction conditions. At the same time, electron-withdrawing substituents in the reactants are more helpful for the reaction. In addition to being in good agreement with the experimental data, the calculated results also provide an important contribution to the further understanding of the mechanism of such reactions.The current work focuses on the DFT calculation of the rational mechanism and catalytic activity of the gold(i)-catalyzed isotetradehydro-Diels–Alder cycloaddition of cyanamides and enamides to substituted 2,6-diaminopyridines. 相似文献
997.
标准化生物样本库是众多重要科研成果快速产业化、应用到临床的重要保证,也是生命科学与生物医药技术自主创新体系中至关重要的环节与保证,是最宝贵资源。从生物样本库的概念和作用、建设进展着手分析生物样本库建设的现状、趋势和问题,并从样本的采集、方法及溯源、伦理问题、设施及环境和系统管理等方面详细论述了生物样本库建设的要素,并列举了目前我国生物样本库相关管理规范,旨在为国家中医药临床研究基地生物样本库建设与发展提供参考。 相似文献
998.
白条党参化学成分研究 总被引:2,自引:0,他引:2
目的:研究甘肃省渭源县大宗种植药材白条党参的化学成分。方法:采用硅胶柱色谱等方法分离纯化,利用各种波谱技术(NMR)及理化性质确定化学结构。结果:从渭源产白条党参中分离得到11个化合物,分别为:橙皮苷(Ⅰ)、β-槐糖正己醇苷(Ⅱ)、苍术内酯Ⅲ(Ⅲ)、党参炔苷(Ⅳ)、lobetyolin in(Ⅴ)、蒲公英萜醇(Ⅵ)、蒲公英萜醇乙酸酯(Ⅶ)、α-菠甾醇(Ⅷ)、9,10,13-三羟基-反-11-十八烯酸(Ⅸ)、β-谷甾醇(Ⅹ)、β-胡萝卜苷(Ⅺ)和蔗糖(Ⅻ)。结论:化合物Ⅰ、Ⅱ和Ⅸ为首次从党参中分离得到。 相似文献
999.
Lin S Wang S Liu M Gan M Li S Yang Y Wang Y He W Shi J 《Journal of natural products》2007,70(5):817-823
A norditerpene glucopyranoside with a novel carbon skeleton (1), eight new aromatic glycosides (2-9), and 25 known glycosides have been isolated from a H2O-soluble portion of an ethanolic extract of the stem bark of Fraxinus sieboldiana. Their structures were determined by spectroscopic and chemical methods. Based on analysis of the NMR data of threo- and erythro-arylglycerols in different solvents, an application of Delta delta C8-C7 values to distinguish threo-arylglycerol and erythro-arylglycerol isomers was proposed. In the in vitro assays, compound 5 displayed TNF-alpha secretion inhibitory activity with an IC50 value of 1.6 microM, compound 6 showed antioxidative activity inhibiting Fe+2-cystine-induced rat liver microsomal lipid peroxidation with an IC50 value of 0.9 microM, and plantasioside (10) showed selective activity against the human colon cancer cell line (HCT-8) with an IC50 value of 3.4 microM. 相似文献
1000.