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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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目的 基于红外热成像技术探讨“扶正温阳法”对阳虚质的影响,探讨阳虚质者红外热图的共性规律,分析判断“扶正温阳法”干预阳虚质人群的疗效。方法 纳入30例阳虚质患者给予益气温阳药物在大椎、肾俞(双侧)、命门等进行穴位贴敷,分别在干预前后运用红外热成像技术测定督脉、腰部、腹部、双手及双足局部温度的变化。结果 干预后阳虚体质患者的督脉、腰部、腹部、双手、双足温度均升高(P<0.05),阳虚体质局部温度得以改善。结论 本研究发现“扶正温阳法”可诱发循经热传导现象,通过调节热能代谢而起到调治阳虚体质的作用,红外热成像技术可用来辅助评价阳虚质的治疗效果,对临床指导制定阳虚质人群的干预方案疗效判定具有指导意义。  相似文献   
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Arterial spin labeling (ASL) imaging is a powerful magnetic resonance imaging technique that allows to quantitatively measure blood perfusion non-invasively, which has great potential for assessing tissue viability in various clinical settings. However, the clinical applications of ASL are currently limited by its low signal-to-noise ratio (SNR), limited spatial resolution, and long imaging time. In this work, we propose an unsupervised deep learning-based image denoising and reconstruction framework to improve the SNR and accelerate the imaging speed of high resolution ASL imaging. The unique feature of the proposed framework is that it does not require any prior training pairs but only the subject's own anatomical prior, such as T1-weighted images, as network input. The neural network was trained from scratch in the denoising or reconstruction process, with noisy images or sparely sampled k-space data as training labels. Performance of the proposed method was evaluated using in vivo experiment data obtained from 3 healthy subjects on a 3T MR scanner, using ASL images acquired with 44-min acquisition time as the ground truth. Both qualitative and quantitative analyses demonstrate the superior performance of the proposed txtc framework over the reference methods. In summary, our proposed unsupervised deep learning-based denoising and reconstruction framework can improve the image quality and accelerate the imaging speed of ASL imaging.  相似文献   
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目的:探讨消化道肿瘤中同源重组修复相关基因(homologous recombination repair related gene,HRR)突变的发生情况及临床意义。方法:共92例消化道肿瘤患者,79例患者进行了血液标本HRR检测,53例患者进行了组织标本HRR检测,40例患者同时行血液和组织的HRR基因检测,收集患者基因检测结果及临床相关资料。结果:在79例患者血液标本检测中发现10例(12.6%)有临床意义HRR突变,在53例患者组织标本检测中发现9例(17.0%)有临床意义HRR突变。40例同时行血液和组织的HRR基因检测患者中常见的有临床意义HRR突变为CDK12突变4例(10.0%)、ATM突变3例(7.5%)、BRCA1突变2例(5.0%)。13例有临床意义HRR突变患者中常见共存突变为TP53突变10例(76.9%)、APC突变5例(38.5%)、PIK3CA突变4例(30.8%)。40例患者中13例患者血液和/或组织中有临床意义HRR突变,27例患者血液和组织中均无任何临床意义HRR突变且两组相比,有临床意义HRR突变组肿瘤突变负荷(tumor mutational burden,TMB)为6.17(2.24~11.52),而未携带HRR突变组TMB为0.4(0~3.75),差异有统计学意义(P<0.05)。40例患者组织检测中7例HRR有临床意义的突变,33例无HRR突变,血液检测中10例HRR有临床意义的突变,30例无HRR突变,一致性检验的Kappa值为0.333(P=0.031)。结论:携带有临床意义HRR突变的消化道肿瘤患者TMB更高,血液和组织检测HRR突变有较好的一致性。  相似文献   
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Vascular injuries that occur during traffic accidents are a commonly neglected aspect that can add more detail to the framework of a case. In this study, we analysed a case series of 150 traffic accidents, 39 of which were marked by microscopically identifiable vascular lesions. The purpose was to identify the presence of carotid injuries in individuals who died due to traffic accidents and had nonpenetrating trauma of the neck. We focused on the discrepancies regarding the macroscopical aspect and the histology and demonstrated how histological analysis of the carotids in cases of trauma can reveal injuries that are attributable to the trauma itself. We conducted a histological analysis of the lesions to describe their distribution and type and investigate potential correlations. The study offers insight on how to examine road accidents that involve traumatic injury of the carotid arteries. Indeed the main task of the forensic pathologist in the case of death is to establish the existence of a causal relationship between the micro- or macroscopic alterations observed in the autopsy and the traumatic event that led to the death of the subject. Thus, further morphological elements were provided to the forensic practitioners that may reveal injuries attributable to the trauma itself and should be evaluated in cases of trauma in traffic accidents.  相似文献   
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总结1例外阴Paget’s病术后创面感染的护理体会,利用伤口评估三角工具对患者创面进行评估,通过使用液体伤口敷料联合银离子敷料控制感染,富血小板血浆技术促进伤口愈合,个体化健康教育提高患者治疗依从性的整体干预方案对伤口进行有效管理,结果显示伤口愈合效果良好。  相似文献   
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《Injury》2023,54(7):110767
AimThis network meta-analysis aims to compare functional outcomes and complications between conservative treatment and surgery for distal radius fractures in patients aged 60 years and over.MethodsWe searched the PubMed, EMBASE, and Web of Science databases for randomized controlled trials (RCTs) assessing the effect of conservative treatment and surgery for distal radius fractures in patients aged 60 years and over. Primary outcomes included grip strength and overall complications. Secondary outcomes included Disabilities of the Arm, Shoulder, and Hand (DASH) scores, Patient-Rated Wrist Evaluation (PRWE) scores, wrist range of motion and forearm rotation, and radiographic assessment. All continuous outcomes were assessed using standardized mean differences (SMDs) with 95% confidence intervals (CIs), and binary outcomes were assessed using odds ratio (OR) with 95% CIs. The surface under the cumulative ranking curve (SUCRA) was used to determine a hierarchy of treatments. Cluster analysis was performed for grouping treatments based on the SUCRA values of primary outcomes.ResultsFourteen RCTs were included to compare conservative treatment, volar lockedplate (VLP), K-wires fixation, and external-fixation. VLP outperformed conservative treatment for 1-year and minimum 2-year grip strength (SMD; 0.28 [0.07 to 0.48] and 0.27 [0.02 to 0.53], respectively). VLP yielded the optimal grip strength at 1-year and minimum 2-year follow-up (SUCRA; 89.8% and 86.7%, respectively). In a subgroup analysis of patients aged 60 to 80 years old, VLP outperformed conservative treatment in DASH and PRWE scores (SMD, 0.33 [0.10, 0.56] and 0.23 [0.01, 0.45], respectively). In addition, VLP had the fewest complications (SUCRA = 84.3%). Cluster analysis suggested that VLP and K-wire fixation were more effective treatment groups.ConclusionEvidence to date demonstrates that VLP provides measurable benefits in grip strength and fewer complications to those 60 years of age and over, and that benefit is not reflected in current practice guidelines. There is a subgroup of patients where K-wire fixation outcomes are similar to those of VLP; defining this subgroup may yield substantial societal benefits.  相似文献   
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