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Kui Li Jiawen Wang Shengxiong Liu Sen Su Chenjian Feng Xiaoxiang Fan Zhiyong Yin 《中华创伤杂志(英文版)》2015,18(2):65-73
Objective: To study the biomechanical mechanism of head injuries beaten with sticks, which is common in the battery or assaultive cases.
Methods: In this study, the Hybrid-III anthropomorphic test device and finite element model (FEM) of the total human model for safety (THUMS) head were used to determine the biomechanical response of head while being beaten with different sticks. Total eight Hybrid-III tests and four finite element simulations were conducted. The contact force, resultant acceleration of head center of gravity, intracranial pressure and von Mises stress were calculated to determine the different biomechanical behavior of head with beaten by different sticks.
Results: In Hybrid-III tests, the stick in each group demonstrated the similar kinematic behavior under the same loading condition. The peak values of the resultant acceleration for thick iron stick group, thin iron stick group, thick wooden stick group and thin wooden stick group were 203.4 g, 221.1 g, 170.5 g and 122.2 g respectively. In finite element simulations, positive intracranial pressure was initially observed in the frontal comparing with negative intracranial pressure in the contra-coup site. Subsequently the intracranial pressure in the coup site was decreasing toward negative value while the contra-coup intracranial pressure increasing toward positive values.
Conclusions: The results illustrated that the stiffer and larger the stick was, the higher the von Mises stress, contact force and intracranial pressure were. We believed that the results in the Hybrid-III tests and THUMS head simulations for brain injury beaten with sticks could be reliable and useful for better understanding the injury mechanism. 相似文献
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Miju Bae Sung Woon Chung Chung Won Lee Up Huh Min Su Kim Seung Hwan Song 《Asian journal of surgery / Asian Surgical Association》2019,42(1):235-239
Background
In Leriche syndrome, postoperative graft thrombosis remains one of the most significant clinical challenges.Methods
We reviewed 51 patients who underwent surgery for aortoiliac occlusive disease at our hospital from January 2007 to December 2014. The factors associated with graft patency were determined using the Cox proportional hazard model.Results
The 2-year prosthetic graft patency rate was 72.5%. Younger age (p = 0.017, Odd ratio (OR) = 1.112), postoperative uncontrolled hypertension (p = 0.044, OR = 3.797), and associated Trans Atlantic Inter-Society Consensus for the Management of Peripheral Arterial Disease II (TASC II) D femoropopliteal lesion (p = 0.008, OR = 11.139) were significantly related factors for prosthetic graft patency after surgical repair. The existing comorbidities of the patients that indicated the need for axillo-bifemoral bypass seemed to be related to lower graft patency or other complications.Conclusions
For better graft patency after an open surgical repair of Leriche syndrome, strict postoperative hypertension control and distal run-off resolution are necessary. 相似文献25.
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<正>慢性阻塞性肺病(chronic obstructive pulmonary diseases,COPD)在临床呼吸科发病率与病死率排名首位,使患者的生命受到严重威胁[1]。COPD患者由于消化、呼吸功衰退,营养吸收功能减弱,同时气道阻力升高,减弱了肺部顺应性,所以伴发能量不足型营养障碍的机率较高[2-3]。出现营养不良的患者往往疾病加重,影响预后,而临床COPD患者疾病严重程度与预后又同肺功能变化密切相关[4]。本文分析了不同营养状况与COPD患者预后的相关性。 相似文献
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Rachel P. Winograd Ned Presnall Erin Stringfellow Claire Wood Phil Horn Alex Duello 《The American journal of drug and alcohol abuse》2019,45(4):333-340
Background: The opioid addiction and overdose crisis continues to ravage communities across the U.S. Maintenance pharmacotherapy using buprenorphine or methadone is the most effective intervention for Opioid Use Disorder (OUD), yet few have immediate and sustained access to these medications. Objectives: To address lack of medication access for people with OUD, the Missouri Department of Mental Health began implementing a Medication First (Med First) treatment approach in its publicly-funded system of comprehensive substance use disorder treatment programs. Methods: This Perspective describes the four principles of Med First, which are based on evidence-based guidelines. It draws conceptual comparisons between the Housing First approach to chronic homelessness and the Med First approach to pharmacotherapy for OUD, and compares state certification standards for substance use disorder (SUD) treatment (the traditional approach) to Med First guidelines for OUD treatment. Finally, the Perspective details how Med First principles have been practically implemented. Results: Med First principles emphasize timely access to maintenance pharmacotherapy without requiring psychosocial services or discontinuation for any reason other than harm to the client. Early results regarding medication utilization and treatment retention are promising. Feedback from providers has been largely favorable, though clinical- and system-level obstacles to effective OUD treatment remain. Conclusion: Like the Housing First model, Medication First is designed to decrease human suffering and activate the strengths and capacities of people in need. It draws on decades of research and facilitates partnerships between psychosocial and medical treatment providers to offer effective and life-saving care to persons with OUD. 相似文献
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Danail Hristozov Alex Zabeo Keld Alstrup Jensen Stefania Gottardo Panagiotis Isigonis Laura Maccalman 《Nanotoxicology》2016,10(9):1215-1228
Several tools to facilitate the risk assessment and management of manufactured nanomaterials (MN) have been developed. Most of them require input data on physicochemical properties, toxicity and scenario-specific exposure information. However, such data are yet not readily available, and tools that can handle data gaps in a structured way to ensure transparent risk analysis for industrial and regulatory decision making are needed. This paper proposes such a quantitative risk prioritisation tool, based on a multi-criteria decision analysis algorithm, which combines advanced exposure and dose-response modelling to calculate margins of exposure (MoE) for a number of MN in order to rank their occupational risks. We demonstrated the tool in a number of workplace exposure scenarios (ES) involving the production and handling of nanoscale titanium dioxide, zinc oxide (ZnO), silver and multi-walled carbon nanotubes. The results of this application demonstrated that bag/bin filling, manual un/loading and dumping of large amounts of dry powders led to high emissions, which resulted in high risk associated with these ES. The ZnO MN revealed considerable hazard potential in vivo, which significantly influenced the risk prioritisation results. In order to study how variations in the input data affect our results, we performed probabilistic Monte Carlo sensitivity/uncertainty analysis, which demonstrated that the performance of the proposed model is stable against changes in the exposure and hazard input variables. 相似文献
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