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ObjectiveTo study the protective effect of total flavonoid in rabdosia rubescens on BIT model by brain ischemic tolerance (hereinafter BIT) model of mice.MethodBIT model is used to block bilateral common carotid arteries and to copy BIT model of mice. After 10 min of transient ischemia for rats in preconditioning group, the mice in the nimodipine group and naoluotong capsule group were given the total flavonoid in rabdosia rubescens (300 mg/kg, 150 mg/kg, 75 mg/kg) for gavage, sham operation group, ischemia/reperfusion injury (hereinafter IRI) group and BIT group were fed with the same volume of 0.5% sodium carboxymethyl cellulose (CMC) once a day for 5 days. After administration for 1 h on day 5 (120 h), the rats in the other groups except for the sham operation group were treated with blood flow block for 30 min and reperfusion for 22 h. The serum NSE level were measured and the brain NO content and NOS activity changes was measured to observe the histopathological changes of brain tissue.ResultsBIT models of mice and in rats were both successfully replicated. The total flavonoid in rabdosia rubescens can decrease the mortality of mice, decrease serum NSE level, increase the content of NO and the activity of NOS in the brain tissue of mice, and improve the pathological damage of cortex and hippocampus of mice.ConclusionThe total flavonoid in rabdosia rubescens can stimulate an endogenous protective mechanism by inducing the release of low levels of cytokines NO and NOS, which reduces the release of serum NSE, relieves the brain tissue ischemia-reperfusion injury, and further improves the protection effect of ischemic preconditioning on brain injury. The damage of brain tissue ischemia and reperfusion, and further improve the ischemia Protective effect of preconditioning on brain injury.  相似文献   
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To increase the menaquinone (MK) content of an Elizabethkingia meningoseptica, site-directed mutagenesis was generated to suppress 4-hydroxybenzoate octaprenyl transferase (UbiA) activity and subsequently blocked the ubiquinone (UQ) biosynthesis pathway. Fourteen conserved residues except L174 and G211 were mutated to analyze the effect of site-directed mutagenesis. The expression of UbiA in twelve mutants was decreased in both mRNA and protein levels, which resulted in the decrease of UQ concentration. Based on MenA expression level, 12 mutants were divided into two groups. Second group such as N72A, D76A, K81A, L139A, and D198A enhanced the expression of MenA, which increased MK production by 127.1%, 87.9%, 96.2%, 109.7% and 130.0% in wt-EmUbiA, respectively. In general, blocking UQ synthesis pathway for by site-directed mutagenesis of the active site of UbiA in E. meningoseptica was a promising strategy to increase MK production in E. meningoseptica.  相似文献   
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目的:研究白芷中有效成分欧前胡素、异欧前胡素和花椒毒酚在大鼠小肠各段的吸收特征。方法:采用大鼠在体单向肠灌流模型结合HPLC法同时测定肠灌流液中欧前胡素、异欧前胡素和花椒毒酚含量的变化,考察高、中、低三组剂量下三种成分在十二指肠、空肠和回肠的吸收特性。结果:三种成分随着剂量的增大,吸收速率常数(Ka)和有效渗透系数(Peff)逐渐增大。三种成分相同剂量下各肠段间吸收均无显著性差异,其吸收大小顺序为:欧前胡素异欧前胡素花椒毒酚。结论:白芷三种主要成分在各肠段均吸收良好,吸收大小呈剂量相关性。  相似文献   
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目的:采用基因芯片技术,分别构建气虚血瘀证大鼠和红花注射液给药处理后气虚血瘀证大鼠的差异基因表达谱,比较并分析,筛选出红花能够治疗气虚血瘀证的关键基因群,并推测其起治疗作用的基因组调控机制。方法:15只SD大鼠随机分为模型组、给药组、空白对照组。模型组和给药组采用疲劳游泳和饥饿饲养处理。造模一周后,给药组尾静脉注射红花注射液(100mg/kg/d),模型组给予相同体积生理盐水;对照组不做任何处理。造模进行两周后处死大鼠,取血检验血流变指标并评价造模情况;另抽取足够的血分离mRNA并逆转录杂交基因芯片;扫描信号分析确定受红花注射液调控的基因;并通过基因数据库查询相关基因功能,结合相关文献分析初步探讨红花作用的机制。结果:两周后经过检验和观察发现模型组大鼠在不同切率下的全血粘度增加,并且其体征表现出虚弱和瘀血的状态、体重下降,确定造模成功;给药组大鼠则相对于模型组的各项检测指标和状态有所改善,确认药物有疗效。在差异基因的比较中,空白组相对于给药组上调基因252条,下调基因54条;给药组相对于模型组上调基因196条,下调基因32条;两次差异表达基因中有16条相同基因,这些差异基因涉及到炎症损伤、免疫调节反应等方面。结论:红花注射液对于气虚血瘀证有治疗作用,在基因层次上是通过抗炎症损伤机制实现的。  相似文献   
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目的:桥本甲状腺炎是一种自身免疫性甲状腺疾病,且其发病率呈逐年上升趋势,在医疗实践中,HT 被认为是原发性甲状腺 功能减退最常见的原因,同时较易发生甲状腺癌和淋巴瘤。另外,HT 缺乏早期诊断标准,临床上发病隐匿且表现多样,病人多不 易察觉而延误治疗。本文旨在应用microRNA 芯片技术系统筛查HT病变甲状腺组织,以此研究并揭示其HT 的miRNA 表达谱 变化。方法:本研究首先采用microRNA芯片技术,对正常甲状腺组织及桥本甲状腺炎甲状腺组织中microRNA 的表达进行比较, 筛选桥本甲状腺炎中差异性表达的miRNAs。结果:与正常甲状腺相比,在桥本甲状腺炎及其合并甲状腺乳头状癌的一侧桥本甲 状腺炎中分别有39 个和25 个miRNAs 分子发生了差异性表达(P<0.05),比较2 组中共有的miRNAs 发现,miR-142-3p、 miR-338-3p、miR-454、miR-146a、miR-29b-1*、miR-150、miR-223 表达上调,miR-654-5p、miR-601、miR-198、miR-1226* 表达下调 (log2 FC≥ 2,P<0.05);而miR-142-5p 在原发性桥本甲状腺炎中表达显著性升高近8 倍(log2 FC=7.959,P<0.01)。结论:我们通 过microRNA芯片,首次直接系统筛查了桥本甲状腺炎病变组织相关miRNA 表达谱,总体上初步掌握了与正常甲状腺相比,桥 本甲状腺炎及合并甲状腺乳头状癌时其miRNA 表达谱的变化情况,为我们后续的研究提供了方向与基础。  相似文献   
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Previous researches mainly focused on the runoff responses to landuse change based on annual, seasonal or monthly time scales, there are few studies based on daily scale. We conducted a comprehensive investigation into runoff responses on the daily scale as well as annual and monthly time scales using SWAT, and compared the impacts of time scales with different time indicators quantitatively. Jinjiang, a coastal catchment of southeast China with a humid sub-tropical climate, was used for simulations. A calibrated SWAT model produced satisfactory reproduction of annual, monthly and daily runoff processes over a nine-year (2002–2010) period at three gauging stations. Runoff was then simulated and compared using the same meteorological input but two different landuse scenarios (1985 and 2006, with reduced forest and increased cropland and urbanized area). The results showed varying change in runoff among three time scales and three catchments. The annual runoff had the smallest increase between two scenarios, monthly runoffs had medium rates (increasing in all months except October–November), and daily runoff had the largest rates with the increase in flood peaks but decrease in drought flows, because of the variable influence on interception/evapotranspiration loss, percolation and antecedent soil water storage. Indicators of different time scales (annual runoff, monthly runoff, maximum 1-day and 5-day flood runoff, minimum 1-day and 7-day runoff) proved appropriate for analysing landuse change impacts.  相似文献   
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