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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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ObjectivesThe purpose of this study was to investigate the prognostic weight of multimorbidity and functional impairment over long-term mortality among older patients discharged from acute care hospitals.DesignA prospective multicenter observational study.Setting and ParticipantsOur series consisted of 1967 adults aged ≥65 years consecutively admitted to acute care wards in Italy, in the context of the Report-AGE project.MethodsAfter signing a written informed consent, all patients underwent comprehensive geriatric assessment by Inter-RAI Minimum Data Set acute care. The primary endpoint of the present study was long-term mortality. Patients were grouped into 3 functional clusters and 3 disease clusters using the K-medians cluster analysis. The association of functional clusters, disease clusters, and Charlson score categories with long-term mortality was investigated through Cox regression analysis and the intercluster classification agreement was further estimated. Finally, the additive effect of either disease clusters or Charlson score on predictive ability of functional clusters was assessed by using changes in Harrell’s C-index and categorical Net Reclassification Index (NRI).ResultsFunctional clusters, disease clusters, and Charlson score were significant predictors of long-term mortality, but the interclassification agreement was poor. Functional clusters predicted mortality with greater accuracy [C-index 0.66, 95% confidence interval (CI) 0.65–0.68] compared with disease clusters (C-index 0.54, 95% CI 0.53–0.56), and Charlson score (C-index 0.58, 95% CI 0.56–0.59). Adding multimorbidity (NRI 0.23, 95% CI 0.14–0.31) or Charlson score (NRI 0.13, 95% CI 0.03–0.20) to functional cluster model slightly improved the accuracy of prediction.Conclusions and ImplicationsFunctional impairment may better predict prognosis compared with multimorbidity, which may be relevant to optimally address individuals’ needs and to design tailored preventive interventions.  相似文献   
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目的探讨内镜经鼻浴缸塞技术在儿童脑脊液鼻漏修补术中的安全性和有效性。方法回顾性分析2016年9月—2019年9月北京儿童医院耳鼻咽喉头颈外科收治的16例脑脊液鼻漏患儿的临床资料。其中男10例,女6例,年龄5~123月龄,中位年龄57.5月龄。患儿常规进行鼻窦薄层CT及MRI检查,并进行了全身麻醉下经鼻内镜浴缸塞技术脑脊液鼻漏修补术。术后定期随访,对手术效果及并发症进行评估。对所有患儿的人口学特点、症状、体征、颅底漏口位置及面积、治疗及预后情况等进行归纳总结。结果16例患儿中,外伤性脑脊液鼻漏7例,先天性脑脊液鼻漏9例。单纯性脑脊液鼻漏2例,合并基底型脑膜脑膨出14例。颅底漏口分别为左侧筛板6例,右侧筛板4例,左侧筛顶2例,右侧筛顶1例,左侧额窦后壁2例,右侧蝶窦顶壁1例。漏口最大直径1~4 mm 4例,5~10 mm 7例,11~20 mm 5例。其中15例手术获得一次性成功,仅1例额窦后壁外伤性脑脊液漏内镜手术修补失败,改由神经外科行开颅修补术。术后随访24~60个月,中位随访时间32.5个月,均未复发或出现并发症。结论内镜经鼻浴缸塞技术法儿童脑脊液鼻漏修补术是一种安全、有效的手术方式,具有操作简便、创伤小、并发症少等优点。  相似文献   
4.
《Orthopaedics and Trauma》2022,36(4):233-238
The application of stem cells, or mesenchymal stem cells (MSC), in trauma and orthopaedics has been growing quickly in the last few decades. MSCs can be applied in tissue regeneration because of their function as a ‘site-regulated drugstore’ as described by Caplan in their release of trophic and immunomodulatory agents to aid focal tissue regeneration. This has been applied to multiple orthopaedic conditions such as osteoarthritis, focal non-unions, osteonecrosis in the femoral head, and ligamentous injuries. The purpose of this review is to summarize the current use of stem cell therapy in orthopaedics alongside the respective evidence. There is preliminary evidence that explores the use of MSCs in orthopaedic conditions which show promise and if developed successfully can positively impact patients whilst saving costs of surgery and minimizing risk. However the presence of low-quality clinical studies and a multitude of unregulated musculoskeletal stem cell therapy clinics that are not supported by the current evidence which is misleading public opinion and expectations. The development of MSCs has its challenges, such regulatory obstacles which can delay a development of a standardized method in preparing MSCs. Further studies with large patient populations and randomized control trials are required to support the use of stem cell treatment over currently available treatments.  相似文献   
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随着人们运动意识水平的增强和社会交通的快速发展,关节损伤患者的数量也大幅增加,而前交叉韧带(ACL)损伤是关节损伤中最常见的韧带损伤。目前治疗ACL损伤的标准手术方式是在关节镜下使用止血带进行前交叉韧带重建手术(ACLR),在ACLR中使用止血带可以减少患者出血,为术者提供一个清晰的手术视野,可为手术提供极大的便利,但止血带的使用并非没有弊端,在骨科快速康复趋势以及患者对术后康复要求提高的情况下,止血带使用所带来的并发症引起了越来越多的关注,为降低止血带并发症的发生,提高患者术后舒适度,加速康复进程,学者们不断探讨如何精准安全的使用止血带。本文为止血带在关节镜下ACLR术中的应用现状、利弊以及应用趋势等作一综述。  相似文献   
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The aim of this study is to provide an improved method for traffic accident reconstruction based on geomatics techniques and numerical simulations. A combination of various techniques was used. First, an unmanned aerial vehicle (UAV), laser scanner and structured-light scanner were used to obtain information on the accident scene, vehicle and victim. The collected traces provided detailed initial impact conditions for subsequent numerical simulations. Then, multi-body system (MBS) simulations were conducted to reconstruct the kinematics of the car-to-pedestrian collision. Finally, a finite element (FE) simulation using the THUMS model was performed to predict injuries. A real-life vehicle-pedestrian collision was used to verify the feasibility and effectiveness of this method. The reconstruction result revealed that the kinematic and injury predictions of the numerical simulations effectively conformed to the surveillance video and investigation of the actual accident. UAV photogrammetry was demonstrated to be more efficient in accident data collection than hand sketch and measurement, and 3D laser scanning enabled an easier and more accurate modeling process of vehicle. The present study shows the feasibility of this method for use in traffic accident reconstruction.  相似文献   
10.
消化道重建是胃癌手术的关键操作之一,其质量直接影响术后相关并发症的发生及远期的营养状况及生活质量,合理选择完全腹腔镜下胃癌根治术后消化道重建的方式对降低术后并发症及改善术后营养状况及生活质量具有积极意义。本文通过对完全腹腔镜下远端胃切除术、全胃切除术常用的消化道吻合方式的优势及不足进行论述,探索目前可能的最优吻合方式,阐述完全腹腔镜近端胃切除术吻合方式的进展,并对生理学、生物力学重建理论的进展进行介绍。  相似文献   
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