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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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Background

Septic shock is often treated with aggressive fluid resuscitation leading to profound fluid overload. The assessment of fluid status relies on suboptimal measures making treatment difficult. Bioelectrical impedance analysis is an alternative but the validity is unclear. The aim of this study was to determine the validity of bioelectrical impedance analysis for fluid measures in patients with septic shock.

Methods

Single-center, prospective observational cohort study. We included adult ICU patients with septic shock. We evaluated the agreement between measures on the left and right side of the patient and measures 1 h apart by two bioelectrical impedance devices. Results are presented as Bland Altman plots with 95% Limits of Agreements (LoA) and as correlations between bioelectrical impedance analysis results and clinical markers of fluids.

Results

Forty-nine patients were included. The agreement between measures on the left and the right side of the patient and after 1 h was overall without bias, but with wide LoA's. Fluid overload 1 h apart showed the most narrow 95% LoA (−2.4–2.9 L). The same wide limits of agreements were observed when comparing devices. For example, total body water with 95% LoA of −14.8 –16.7 L. Correlations between bioelectrical impedance analysis and clinical measures were low but statistically significant.

Conclusions

In patients with septic shock bioelectrical impedance analysis had no systematic errors or bias, but wide limits of agreement, indicating that the devices have a large and uncorrectable random error. Fluid status by bioelectrical impedance analysis is not sufficiently accurate to guide treatment in this group of patients.  相似文献   
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输尿管上段结石为临床中常见泌尿系结石类型之一,如不能及时诊治,可引起重度积水、泌尿系感染,甚至脓毒血症,对患者肾功能、健康造成严重影响。随着微创治疗技术在泌尿系结石中应用,微创治疗方法能降低对患者造成治疗性创伤,降低相关并发症发生率,促进患者康复,了解临床中微创治疗输尿管上段结石方法,对临床中合理治疗输尿管上段结石有重要价值。  相似文献   
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Introduction

Left ventricular (LV) dysfunction is estimated to occur in 10%–25% of the general intensive care unit (ICU) population and is frequently seen as regional wall motion abnormalities (RWMAs). Although RWMA is mostly attributed to myocardial ischemia or infarction, some studies have suggested that nonischemic RWMA might also be prevalent. We sought to establish that RWMA can be seen in critically ill patients with normal coronary arteries and to explore reasons for RWMA in this population.

Methods

In this retrospective study, data from the hospital angiography register and the ICU register were collated between 2012 and 2019. Patients were identified who underwent angiography in conjunction with their ICU stay and had RWMA on echocardiography. Patients were divided into either those with non-obstructed or those with obstructed coronary arteries. Cardiac magnetic resonance imaging (cMRI) examinations were reviewed if they had been performed on patients with non-obstructed coronaries.

Results

We identified 53 patients with RWMA and non-obstructed coronary arteries and 204 patients with RWMA and obstructed coronary arteries. Patients with non-obstructed coronary arteries were more often female, younger, and had fewer cardiovascular risk factors. They less commonly had ST elevation, but more frequently had T-wave inversion or serious arrhythmias. Troponin levels were higher in patients with obstructed coronary arteries, but NT-proBNP was similar between the groups. There were no differences in risk-adjusted 90-day mortality between patients with non-obstructed versus obstructed coronary arteries (OR 1.21, [95% CI 0.56–2.64], p = .628). In those with non-obstructed coronary arteries, follow-up echocardiography was available for 38 patients, of whom 30 showed normalization of cardiac function. Of the 14 patients with non-obstructed coronary arteries on whom cMRI was performed, 7 had a tentative diagnosis of Takotsubo syndrome or myocardial stunning; 4 had a myocardial infarction (preexisting in 3 cases); 1 patient had acute myocarditis; 1 patient had post-myocarditis; and 1 patient was diagnosed with dilated cardiomyopathy.

Conclusion

RWMA can be seen to occur in critically ill patients in the absence of coronary artery obstruction. Several conditions can cause regional hypokinesia, and cMRI is useful to evaluate the underlying etiology.  相似文献   
8.
BackgroundFoot orthoses (FOs) are used to manage foot pathologies such as plantar fasciopathy. 3D printed custom-made FOs are increasingly being manufactured. Although these 3D-printed FOs look like traditionally heat-moulded FOs, there are few studies comparing FOs made using these two different manufacturing processes.Research questionHow effective are 3D-printed FOs (3D-Print) compared to traditionally-made (Traditional) or no FOs (Control), in changing biomechanical parameters of flat-footed individuals with unilateral plantar fasciopathy?MethodsThirteen participants with unilateral plantar fasciopathy walked with shoes under three conditions: Control, 3D-print, and Traditional. 2 × 3 repeated measures analysis of variance (ANOVAs) with Bonferroni post-hoc tests were used to compare discrete kinematic and kinetic variables between limbs and conditions. Waveform analyses were also conducted using statistical parametric mapping (SPM).ResultsThere was a significant condition main effect for arch height drop (p = 0.01; ηp2 =0.54). There was 0.87 mm (95% CI [−1.84, −0.20]) less arch height drop in 3D-print compared to Traditional. The SPM analyses revealed condition main effects on ankle moment (p < 0.001) and ankle power (p < 0.001). There were significant differences between control condition and both 3D-print and Traditional conditions. For ankle moment and power, there were no differences between 3D-print and Traditional conditions.Significance3D-printed FOs are more effective in reducing arch height drop, whist both FOs lowered ankle plantarflexion moment and power compared to no FOs. The results support the use of 3D-printed FOs as being equally effective as traditionally-made FOs in changing lower limb biomechanics for a population of flat-footed individuals with unilateral plantar fasciopathy.  相似文献   
9.
随着对肿瘤热疗和肿瘤免疫微环境(TIME)的深入研究,近年来热疗对TIME的作用越来越受到学者们的重视。本文就目前国内外研究进展,对热疗与TIME中几类主要免疫细胞和免疫相关细胞因子的影响及作用机制作一综述。全面而透彻的了解热疗对TIME的调控作用,有助于为肿瘤治疗提供新的思路和方法。  相似文献   
10.
目的探究临床用乌司他丁辅助治疗重症感染性休克的治疗效果。方法90例重症感染性休克患者,随机分为观察组与对照组,每组45例。对照组患者采用西医常规治疗,观察组患者在对照组基础上联合乌司他丁治疗。比较两组患者治疗效果、体温情况、感染情况以及治疗前后白细胞计数、白细胞介素-6(IL-6)水平、格拉斯哥昏迷量表(GCS)评分、急性生理功能和慢性健康状况评分系统Ⅱ(APACHEⅡ)评分。结果治疗后,观察组白细胞计数(7.34±1.32)×10^9/L低于对照组的(9.41±1.16)×10^9/L,差异具有统计学意义(P<0.05)。治疗后,观察组高热、感染体征发生率分别为97.78%、86.67%,均高于对照组的82.22%、62.22%,差异具有统计学意义(P<0.05);观察组体温恢复时间、感染消失时间分别为(7.19±1.39)、(3.88±0.89)d,均短于对照组的(9.81±1.88)、(10.76±1.57)d,差异具有统计学意义(P<0.05)。观察组患者血清IL-6为(4.27±0.95)μg/L低于对照组的(9.58±1.07)μg/L,差异具有统计学意义(P<0.05)。观察组患者GCS评分和APACHEⅡ评分较治疗前均有所改善,GCS评分(8.19±1.59)分、APACHEⅡ评分(8.83±0.82)分均优于对照组的(6.81±1.82)、(14.71±3.52)分,差异均具有统计学意义(P<0.05)。观察组患者治疗总有效率95.56%明显高于对照组的77.78%,差异具有统计学意义(χ^2=6.154,P<0.05)。结论乌司他丁具有较好的抗炎效果,与西医治疗相结合可以提高临床疗效,加快重症感染性休克患者退热速度,缩短感染时间,降低白细胞计数及血清IL-6水平,改善GCS评分和APACHEⅡ评分,临床疗效较好。  相似文献   
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