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1.
Guo-Quan Shi Huajun Zhu & Zhen-Guo Yan 《Communications In Computational Physics》2022,31(4):1215-1241
A priori subcell limiting approach is developed for high-order flux reconstruction/correction procedure via reconstruction (FR/CPR) methods on two-dimensional unstructured quadrilateral meshes. Firstly, a modified indicator based on
modal energy coefficients is proposed to detect troubled cells, where discontinuities
exist. Then, troubled cells are decomposed into nonuniform subcells and each subcell has one solution point. A second-order finite difference shock-capturing scheme
based on nonuniform nonlinear weighted (NNW) interpolation is constructed to perform the calculation on troubled cells while smooth cells are calculated by the CPR
method. Numerical investigations show that the proposed subcell limiting strategy on
unstructured quadrilateral meshes is robust in shock-capturing. 相似文献
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胃癌作为临床最常见的肿瘤之一,常因确诊疾病较晚而影响治疗效果,胃镜活检后的病理虽然作为确诊的金标准,但是由于此方式过程痛苦,操作复杂,费用较高,且具有侵入性,可能会导致患者拒绝操作而难普及于临床,因此积极找寻胃癌有效的监测指标十分必要。近年来,很多学者研究维生素与胃癌的相关关系,并试图通过摄取某些维生素降低胃癌发生率,延缓病情及改善预后,也有通过检测血清中维生素的水平给早期胃癌的诊断提供帮助。本文就同型半胱氨酸、维生素D、维生素C、维生素E、维生素B12及叶酸在胃癌中的作用机制,及其在血清中水平与胃癌关系的相关研究进展进行简要综述,为临床胃癌诊疗提供新思路。 相似文献
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目的 筛选荔枝草治疗急性咽炎的有效部位,研究治疗急性咽炎的作用机制,为荔枝草资源的药食两用开发提供理论依据。方法 通过二甲苯致小鼠耳肿胀试验筛选荔枝草抗炎有效部位,采用氨水刺激喉部法建立大鼠急性咽炎模型,通过行为学观察、ELISA双抗夹心检测、病理形态学观察和咽部组织蛋白表达研究乙酸乙酯部位对大鼠急性咽炎的治疗效果。结果 荔枝草乙酸乙酯提取物对二甲苯致小鼠耳肿胀有明显的抑制作用,氨水刺激建立的急性咽炎模型符合急性咽炎动物模型特征,乙酸乙酯部位提取物可显著改善急性咽炎大鼠的咽部病理形态学表现。不同剂量治疗组大鼠血清及咽部组织中IL-1β、IL-6及TNF-α炎性因子数量均下降,高剂量组下降最为明显。荔枝草乙酸乙酯提取物可明显增加大鼠咽部组织IκBα蛋白表达,降低NF-κBp65蛋白表达。结论 荔枝草乙酸乙酯部位提取物对急性咽炎具有治疗作用,可能与抑制咽部炎症病理改变的发生,能调节血液中炎症因子、抑制NF-κB表达和IκBα解离有关。 相似文献
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《Revista portuguesa de cardiologia》2022,41(4):311-320
Aims and objectivesVitamin D deficiency is a common finding and there is a suggested association with hypertension. Resistant hypertension is a clinical problem observed in 5–30% of hypertensive patients. Renal denervation (RDN) has been used for patients with resistant hypertension and has proven to lower blood pressure. Our primary goal was to assess the vitamin D serum concentration as a predictor of blood pressure response to RDN in highly selected patients.MethodsThis prospective, nonrandomized, single-center study included 24 patients treated with RDN. Based on their one-year response after RDN, patients were classified as responders or non-responders at six months or at 12 months.ResultsThe median follow-up was 52 months (range, 14-91 months). After RDN, 17 patients (70.8%) had a reduction >5 mmHg in the mean systolic blood pressure, at the first six months of follow-up. At 12 months, 20 patients (83.3%) were responders. Vitamin D levels at baseline (15.1±4.8 vs. 24.2±8.8 ng/ml) and at six months (16.6±7.2 vs. 25±9.2 ng/ml) were lower in early non-responders compared to early responders (p=0.008), without significant variation during follow-up. Even though Vitamin D levels were lower in the total responder's group, no statistically significant differences were found (p=ns).ConclusionIn patients with resistant hypertension, low vitamin D concentrations were associated with an absence of early response to RDN. 相似文献
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目的 探究注意缺陷多动障碍(ADHD)患儿血清25羟基维生素D[25(OH)D]、微量元素表达水平及临床意义。方法 选取2019年4月至2020年11月本院诊治的84例ADHD患儿进行研究(ADHD组),依据ADHD分型标准将患儿分为注意缺陷为主型组(28例)、多动为主型组(33例)、混合型组(23例),并选取同期84例体检健康儿童进行对照研究(对照组)。采用高效液相色谱-串联质谱法检测所有受试儿童血清25(OH)D水平;检测血清铁(Fe)、磷(P)、镁(Mg)、钙(Ca)、铜(Cu)、锌(Zn)、铅(Pb)水平;Pearson法分析ADHD患儿血清25(OH)D水平与Cu、Zn、Pb水平的相关性;Logistic回归分析ADHD发生的影响因素;受试者工作特征(ROC)曲线分析血清25(OH)D、Zn、Pb水平对ADHD的诊断价值。结果 ADHD组血清25(OH)D、Cu、Zn水平均显著低于对照组(P<0.05),Pb水平显著高于对照组(P<0.05);注意缺陷为主型组、多动为主型组、混合型组患儿血清25(OH)D、Fe、P、Mg、Ca、Cu、Zn、Pb水平比较,差异无统计学意义(P>0.05);ADHD患儿血清25(OH)D水平与Cu、Zn水平均呈正相关(P<0.05),与Pb水平呈负相关(P<0.05);25(OH)D、Zn是影响ADHD发生的保护因素(P<0.05),Pb是影响ADHD发生的危险因素(P<0.05);血清25(OH)D、Zn、Pb水平诊断ADHD的曲线下面积(AUC)分别为0.773、0.770、0.772,截断值分别为21.01 ng/mL、16.05 μmol/L、50.69 μg/L,相应灵敏度分别为82.1%、77.4%、63.1%,特异度分别为67.9%、71.4%、88.1%;三者联合诊断ADHD的AUC为0.883,其灵敏度、特异度分别为81.0%、81.0%。结论 ADHD患儿血清25(OH)D、Cu、Zn水平降低,Pb水平升高,25(OH)D、微量元素水平与ADHD患儿类型无关,25(OH)D、Zn、Pb联合有助于临床筛查ADHD患儿。 相似文献
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Curcumin Encapsulated into Biocompatible Co-Polymer PLGA Nanoparticle Enhanced Anti-Gastric Cancer and Anti-Helicobacter Pylori Effect 下载免费PDF全文
Jawed AlamFahima DilnawazSanjeeb Kumar SahooDurg Vijai Singh Asish Kumar MukhopadhyayTahziba HussainSanghamitra Pati 《Asian Pacific journal of cancer prevention》2022,23(1):61-70
Background: The current disadvantages (high cost, toxicity, resistance) of chemotherapy for gastric cancer opted people for alternative therapy from natural source. Curcumin (natural product) possess multiple biological activities but low bio-availability limits their uses as therapeutic. The Nano-formulation of curcumin increased the bioavailability and productivity of anti-cancer and anti-bacterial properties. The present study was initiated to determine the anti-cancer and anti-bacterial effect of Nano curcumin against gastric cancer and H. pylori. Methods: Curcumin loaded PLGA nanoparticles (CUR-NPs) was prepared by single emulsion solvent evaporation method. The MIC were determined using agar dilution method to find the anti-H. Pylori activity of Nano curcumin. The cytotoxicity of Nano curcumin was evaluated by MTT assay and the apoptotic effect (cell cycle arrest and morphology change) was shown by PI staining and microscopy. Results: The MIC of nanocurcumin and curcumin for all four H. pylori strains were 8 µg/ml and 16 µg/ml respectively. The inhibition rate of gastric cancer cells after treatment with curcumin was increased from 6% to 67% for 24h, from 8% to 75% for 48h, from 10% to 83% for 72h. In case of nanocurcumin, the inhibition rate increased from 7% to 69% for 24h, 11% to 87% for 48h and 16% to 97% for 72h. The IC50 of curcumin and Nano-curcumin were 24.20 µM and 18.78 µM respectively for 72 h. The population of cells in sub-G0 population increased from 4.1% in the control group to 24.5% and 57.8% when treated with curcumin and nanocurcumin respectively. After 72h of treatment with nanocurcumin, the apoptotic cells population increased as compared to native curcumin treated cells. Conclusion: The Nano curcumin might be used as a potential therapeutics against gastric cancer and H. Pylori. There is need of further in vivo study in order to validate CUR-NPs activity. 相似文献