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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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OBJECTIVES: The purpose of this study was to determine the clinical and biophysical characteristics of a novel SCN5A mutation. BACKGROUND: Brugada syndrome and isolated cardiac conduction defect have been linked to SCN5A mutations. METHODS: Eleven members of a western European family underwent electrophysiologic investigations and mutation analysis of the SCN5A gene. Wild-type and mutant SCN5A channels were expressed in HEK293 cells, and whole cell currents were studied using patch clamp procedures. RESULTS: A novel mutation, R376H, in the first pore segment of SCN5A variably causes Brugada syndrome and/or conduction disease in a single family. Biophysical analysis demonstrated a significant current reduction for the mutant, a pathophysiologic profile consistent with Brugada syndrome and isolated cardiac conduction defect. Among 11 family members, 9 were carriers of the mutation. The proband's initial presentation was a saddleback Brugada ECG, atrial flutter, and diffuse conduction disturbances. He had no inducible ventricular arrhythmias but experienced sudden cardiac death. His brother was affected by atrial flutter and had a clear conduction disorder, but he did not display baseline or evocable ECG signs of Brugada syndrome. He received an implantable cardioverter-defibrillator that delivered one appropriate shock after 1 year of follow-up. The phenotype in the family members was highly variable and ranged from noninducible and inducible asymptomatic carriers of the mutations to isolated conduction disease and to symptomatic Brugada syndrome. CONCLUSIONS: We describe the functional characterization of a novel SCN5A pore mutation, R376H, with variable clinical expression in the same family. Differentiating between electrophysiologic entities (Brugada syndrome-isolated cardiac conduction defect) is more challenging. Recognition of factors modifying the clinical presentation may be important for clinical decision making.  相似文献   
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胫骨平台骨折合并软组织损伤的临床分析与治疗   总被引:1,自引:0,他引:1  
目的:总结分析各种胫骨平台骨折合并不同类型软组织损伤中的相互关系,探索其诊断与治疗策略。方法:自1995年10月至2004年1月共治疗胫骨平台骨折合并软组织损伤143例。所有病例均行开放复位内固定,对不同类型软组织损伤同时采取相应的处理方法。结果:术后随访129例,随访时间6到27个月,平均16个月;骨折均于12周内愈合,所有患者均恢复了患肢的正常力线,患肢稳定。结论:胫骨平台骨折合并软组织损伤的诊断必须早期、全面、详细、明确,坚强的内固定基础上,对不同类型的软组织损伤必须正确处理,术后应注意被动伸膝及CPM功能锻炼,这样才能最大程度挽救膝关节功能,减少晚期并发症。  相似文献   
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Bulletin of Environmental Contamination and Toxicology - Heavy metals pollution and salinization of soils are widely distributed in agricultural soils. This study investigated the effects of five...  相似文献   
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It has been hypothesized that the defects of insulin receptors may play an important role in the insulin resistance of coronary heart disease. As a test of this hypothesis, 20 male patients with myocardial infarction, 20 male patients with type 2 diabetes mellitus and 20 normal subjects as control were investigated.Plasma insulin were determined; at the meantinme, insulin receptors of erythrocyte were indentified by means of 125 I -labeled insulin binding to erythrocytes while the affinity constants (K1 ,K2) and the number of receptors with different affinity and capacity (Q1,Q2) were calculated according to Scatchard's graphic method. The results showed that the number of insulin receptors with low affinity (Q2) on erythrocytes,K1, K, were lower in patients with myocardial infarction than those in controls ; and Q2, K1 in patents with type 2 diabetes mellitus were also lower. So we concluded that the mechanism of insulin resistance in coronary heart disease might be associated with insulin receptor and affinity abnormalities ,differed from that in diabetic state with some degree of post-receptor defects, which suggests that there may be an interrelationship among insulin receptor defects, insulin resistance,hyperinsulinemia in developing coronary heart disease.  相似文献   
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目的 研究自发性高血压大鼠(SHR)左心室肥厚与血压、心肌局部血管紧张素Ⅱ的关系。方法 取SHR(n=40)及正常对照组WKY(n=41),分为4周龄、8周龄、12周龄、24周龄及36周龄组.测收缩压、体重,左心室重量及用放免法测定心肌局部血管紧张素(AⅡ)含量,并进行两两线性相关分析。结果 通过对5个年龄段的SHR和WKY的收缩压、左心室重与体重比(LVM/BW)及心肌局部AⅡ含量的测定结果发现三者之间存在相关性,其中AⅡ与心肌肥厚有明显相关性。结论 血压与AⅡ在SHR大鼠的左心室肥厚中起着重要作用。  相似文献   
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自发性高血压大鼠血管结构与功能的观察   总被引:2,自引:0,他引:2  
观察16周龄SHR大鼠与同龄WKY大鼠之间血管结构与功能的差异及其在高血压形成中的作用。用尾袖法测量大鼠动脉血压,动脉环实验测定主动脉与肠系膜动脉血管平滑肌的反应性,用肉眼数点计算法测定主动脉中膜腔壁厚度/管腔面积(W/L),图像分析仪摄像求积法测定肠系膜动脉W/L。结果:16周龄SHR大鼠血压明显高于WKY大鼠(28.24±1.12kPa与17.15±0.75kPa,P<0.05)。SHR大鼠主动脉和肠系膜动脉的W/L明显大于WKY大鼠(0.33±0.03与0.24±0.05,P<0.05;及0.75±0.09与0.26±0.02,P<0.05)。硝普钠引起的SHR大鼠血管舒张率明显低于WKY,而去甲肾上腺素引起的SHR大鼠血管收缩率明显高于WKY。结果表明:SHR大鼠阻力血管结构的改变可能是高血压形成的重要因素,SHR大鼠血管功能改变与高血压形成密切相关。  相似文献   
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目的:观察加味四妙勇安汤联合前列地尔注射液治疗下肢动脉闭塞疗效。方法:将90例下肢动脉闭塞症患者随机分为治疗组和对照组,各45例。治疗组给予加味四妙勇安汤联合前列地尔注射液治疗,加味四妙勇安汤每日1剂,水煎服,连用3周;对照组给予前列地尔注射液治疗。其它情况处理,两组同样对待。前列地尔注射液2 m L+生理盐水10 m L缓慢静注,连续治疗两周为1个疗程,每20天1个疗程,共治疗4个疗程,其他治疗两组相同。观察两组患者治疗结束后临床疗效、血浆血脂及两组病人治疗前后症状变化。结果:治疗组患者总有效率为97.8%,高于对照组的88.9%,比较两组患者的总有效率,经检验后得出差异有统计学意义(χ2=4.94,P=0.026)。两组患者治疗结束后的总胆固醇、低密度脂蛋白均较治疗前有所降低,而高密度脂蛋白较治疗前则有所升高,与对照组相比差异具有统计学意义(P<0.05)。两组患者的ABI值也较治疗前有所升高,但治疗组ABI升高值明显大于对照组,差异具有统计学意义(P<0.03)。两组患者症状体征积分比较,差异具有统计学意义(P<0.001)。结论:加味四妙勇安汤联合前列地尔注射液治疗下肢动脉闭塞症临床疗效肯定,可能通过降低患者的血浆血脂而起作用。  相似文献   
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Background:Whether the addition of Chinese herbal medicine (CHM) in routine western medicines for post-stroke depression yields additional therapeutic effects still remains to be controversial. This study aimed to assess the efficacy and safety of combination of CHM with routine western medicines versus routine western medicines alone in patients with post-stroke depression (PSD).Methods:Electronic databases such as PubMed, EmBase, Cochrane library, and China National Knowledge Infrastructure were systematically searched from inception till October 2019. Studies designed as randomized controlled trials (RCTs) and that investigated the therapeutic effects of CHM plus routine western medicines (CHM group) versus routine western medicines alone (control group) in PSD patients were eligible. The relative risk (RR) and weighted mean difference (WMD) with 95% confidence interval (CI) were used to assess the categories and continuous data using random-effects model. Software STATA was applied to perform statistical analysis (Version 10.0; StataCorp, TX,).Results:A total of 18 RCTs involving a total of 1,367 PSD patients were selected for final analysis. The effective rate in CHM group was significantly higher than that in control group (RR: 1.18; 95%CI: 1.12–1.24; P < .001). Moreover, patients in CHM group showed association with lower Hamilton Depression Rating Scale (WMD: -3.17; 95%CI: -4.12 to -2.22; P < .001) and Scandinavian Stroke Scale (WMD: -3.84; 95%CI: -5.73 to -1.96; P < .001) than those in control group. Furthermore, patients in CHM were associated with high level of Barthel Index than those in control group (WMD: 11.06; 95%CI: 4.01 to 18.10; P = .002). Finally, patients in CHM group had lower risk of gastrointestinal (RR: 0.49; 95%CI: 0.31–0.77; P = .002) and neurological (RR: 0.50; 95%CI: 0.33–0.75; P = .001) adverse events than those in control group.Conclusions:The study findings revealed that addition of CHM to routine therapies could improve the therapeutic effects and reduce gastrointestinal or neurological adverse events.  相似文献   
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