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1.
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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Information regarding the impact of the coronavirus disease 2019 (COVID-19) pandemic on cervical cancer in mainland China is lacking. We explored its impact on the hospital attendance of patients with primary cervical cancer. We included 1918 patients with primary cervical cancer who initially attended Harbin Medical University Cancer Hospital between January 23, 2019, and January 23, 2021. Attendance decreased by 31%, from 1135 in 2019 to 783 in 2020, mainly from January to June (𝜒2 = 73.362, P < .001). The percentage of patients detected by screening decreased from 12.1% in January-June 2019 to 5.8% in January-June 2020 (𝜒2 = 7.187, P = .007). Patients with stage I accounted for 28.4% in 2020 significantly lower than 36.6% in 2019 (𝜒2 = 14.085, P < .001), and patients with stage III accounted for 27.1% in 2020 significantly higher than 20.5% in 2019 (𝜒2 = 11.145, P < .001). Waiting time for treatment was extended from 8 days (median) in January-June and July-December 2019 to 16 days in January-June (𝜒2 = 74.674, P < .001) and 12 days in July-December 2020 (𝜒2 = 37.916, P < .001). Of the 179 patients who delayed treatment, 164 (91.6%) were for the reasons of the healthcare providers. Compared to 2019, the number of patients in Harbin or non-Harbin in Heilongjiang Province and outside the province decreased, and cross-regional medical treatment has been hindered. The COVID-19 pandemic has negatively impacted cervical cancer patient attendance at the initial phase. These results are solid evidence that a strategy and mechanism for the effective attendance of cervical cancer patients in response to public health emergencies is urgently needed.  相似文献   
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目的 通过研究明确苗药五藤膏外敷缓解胶原诱导性关节炎(CIA)大鼠关节局部炎症和骨破坏的机制,证实苗医外治就近驱邪的作用。方法 将70只Wistar大鼠随机分为空白组、模型组、苗药五藤膏高、中、低剂量组、扶他林组及IL-17阻断组,每组10只。除空白组外,其余6组均构建CIA模型,并给予相应的外敷治疗。观察大鼠一般情况,HE染色进行病理学分析,TRAP染色检测OC生成,ELISA检测各炎症因子的含量,RT-PCR和WB分别检测RANKL的基因及蛋白表达。结果 苗药五藤膏能改善CIA大鼠破骨细胞浸润及关节病理性结构,并降低RANKL蛋白、基因表达以及TNF-α、IL-1、IL-6、IL-17含量。结论 苗药五藤膏外敷剂对CIA大鼠的治疗机制可能与降低致炎因子的分泌,抑制RANKL及OC的表达相关。  相似文献   
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ObjectivesSystematic review of the scientific literature dedicated to treatment modalities and results for aural tuberculosis published since the start of the 21st century.Material and methodsSearch of the Medline, Cochrane and Embase databases for the period 2000 - 2020. Selection of articles in English, French and Spanish devoted to clinical cases and series documenting treatment of auricular tuberculosis. Extraction of data on pre-established files documenting treatment modalities and results. Reading of articles by two authors. Analysis performed according to SWiM guidelines, evaluating cure, tuberculosis-related death, treatment-related complications, improvement in facial palsy, and hearing sequelae rates.ResultsOne hundred and twenty eight articles: 118 case reports (159 patients) and 10 cohorts (177 patients) from 42 countries were analyzed. Female/male sex ratio was 1.2 with ages ranging from 1 month to 87 years. Medical treatment consisted in 5 to 24 months’ antitubercular antibiotic treatment using 2 to 8 antibiotics. Mastoidectomy, tympanoplasty and facial nerve decompression were associated to medical treatment in 64.7%, 17.4% and 6.2% of cases, respectively. Overall rates of cure, death, treatment-related complications, facial sequelae and hearing sequelae were 96.8%, 2%, 9.5%, 35.8% and 75.5%. In case reports, BCG vaccination did not appear to protect against facial palsy and severe intracranial complications (P > 0.6). There was no significant correlation (P > 0.3) between death and the clinical variables tested, and facial nerve decompression did not appear to influence outcome for facial function (P = 0.4).ConclusionMedical treatment is very effective but not without risk of death, complications and sequelae. It is the same as for pulmonary tuberculosis. Indications for and benefit of major auricular surgery during medical treatment deserve further studies.  相似文献   
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青少年特发性脊柱侧凸发病率较高且病情复杂,对青少年身心健康可造成显著影响,但其因病因不明,临床尚未形成治疗共识。近年来基于患者医学影像进行仿真建模的有限元法生物力学分析在青少年特发性脊柱侧凸治疗及其病因研究中已经有了一系列的应用。本文即从非手术治疗、手术治疗、病因研究、现有局限等角度对有限元法生物力学分析在青少年特发性脊柱侧凸中的应用进行综述,以期为临床实践及相关研究提供参考。  相似文献   
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Diabetic foot ulcer is a devastating complication of diabetes mellitus and significant cause of mortality and morbidity all over the world and can be complex and costly. The development of foot ulcer in a diabetic patient has been estimated to be 19%-34% through their lifetime. The pathophysiology of diabetic foot ulcer consist of neuropathy, trauma and, in many patients, additional peripheral arterial disease. In particular, diabetic neuropathy leads to foot deformity, callus formation, and insensitivity to trauma or pressure. The standard algorithms in diabetic foot ulcer management include assessing the ulcer grade classification, surgical debridement, dressing to facilitate wound healing, off-loading, vascular assessment (status and presence of a chance for interventional vascular correction), and infection and glycemic control. Although especially surgical procedures are sometimes inevitable, they are poor predictive factors for the prognosis of diabetic foot ulcer. Different novel treatment modalities such as nonsurgical debridement agents, oxygen therapies, and negative pressure wound therapy, topical drugs, cellular bioproducts, human growth factors, energy-based therapies, and systematic therapies have been available for patients with diabetic foot ulcer. However, it is uncertain whether they are effective in terms of promoting wound healing related with a limited number of randomized controlled trials. This review aims at evaluating diabetic foot ulcer with regard to all aspects. We will also focus on conventional and novel adjunctive therapy in diabetic foot management.  相似文献   
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《Molecular therapy》2022,30(5):1952-1965
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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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