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151.
BackgroundTalus fractures are rare in children but can lead to severe outcomes if untreated. The Ilizarov external fixator has been used in the treatment of a variety of lower extremity pathologies. The purpose of this study was to investigate the clinical outcomes of talus body fractures treated with the Ilizarov external fixator.Case PresentationFour male pediatric patients (age range, 5–11 years) with talus body fractures who were treated by open reduction and internal fixation combined with Ilizarov external fixator between November 2015 and April 2016 were reviewed. Mean follow‐up period was 4 years (range, 4–5). Clinical outcome was evaluated using the clinical rating scale of the American Orthopaedic Foot and Ankle Society (AOFAS). All four patients achieved good to excellent results at the last follow‐up. None of the patients developed avascular necrosis. One patient developed automatic fusion of tibiotalar joint.ConclusionUse of the Ilizarov external fixator to gain early range of motion is a valuable option for treatment of talus body fractures in children.  相似文献   
152.

目的:总结新型冠状病毒(SARS-CoV-2)感染相关急性黄斑区神经视网膜病变(AMN)的神经眼科特征。

方法:纳入2022-12-27/2023-02-01就诊于西安市第一医院(西北大学附属第一医院)神经眼科并经相关检查确诊为AMN的患者8例(6例女性,2例男性)共14眼纳入本次研究。所有患者病前均有SARS-CoV-2感染史。收集患者的临床资料。纳入最佳矫正视力(BCVA)、非接触间接眼压测定、眼底彩色照相、近红外成像(IR)、频域光学相干断层扫描(SD-OCT)、OCT血流成像(OCTA)、眼底荧光素血管造影(FFA)、吲哚菁绿血管造影(ICGA)、视野、视觉诱发电位(VEP)和视网膜电流图(ERG)检查结果。对纳入患者的神经眼科特征进行分析总结。

结果:纳入的8例患者年龄20-43(平均30±6.63)岁。病前3-11(平均5±3.51)d有SARS-CoV-2感染史,8例患者中有6例在感染SARS-CoV-2的5 d内出现视觉症状。患者的临床表现为视力下降或视物遮挡感; 纳入患者的视力0.08-1.0; 视野缺损表现为中心、旁中心暗点或合并周边暗点。VEP可见P100或P2峰时延迟; ERG提示视网膜感光细胞 功能受损。在疾病早期,SARS-CoV-2感染相关AMN患者可能存在视力、视野和视网膜外层病变大小及形状可能不匹配的情况,并发现视力越低,VEP峰时越迟。

结论:除眼底多模影像,SARS-CoV-2感染相关AMN的神经眼科特征需要临床医师关注,视功能及电生理可以辅助临床更加全面评估患者及判断预后。  相似文献   

153.
目的 比较腓骨髓内钉与切开复位钉板系统治疗腓骨远端骨折的疗效.方法 回顾性分析2017年10月至2019年10月于锦州医科大学附属第一医院采用手术治疗腓骨骨折的患者,按照纳入、排除标准筛选病例,最终A组髓内钉组25例纳入研究、B组钉板内固定组35例纳入研究.比较两组入院至行腓骨手术的时间,手术时长,腓骨术口总长度,AO...  相似文献   
154.
155.
Graphene is one of the most promising two-dimensional nanomaterials with broad applications in many fields. However, the variations and fluctuations in the material and geometrical properties are challenging issues that require more concern. In order to quantify uncertainty and analyze the impacts of uncertainty, a stochastic finite element model (SFEM) is proposed to propagate uncertainty for carbon atomic interactions under resonant vibration. Compared with the conventional truss or beam finite element models, both carbon atoms and carbon covalent bonds are considered by introducing plane elements. In addition, the determined values of the material and geometrical parameters are expanded into the related interval ranges with uniform probability density distributions. Based on the SFEM, the uncertainty propagation is performed by the Monte Carlo stochastic sampling process, and the resonant frequencies of graphene are provided by finite element computation. Furthermore, the correlation coefficients of characteristic parameters are computed based on the database of SFEM. The vibration modes of graphene with the extreme geometrical values are also provided and analyzed. According to the computed results, the minimum and maximum values of the first resonant frequency are 0.2131 and 16.894 THz, respectively, and the variance is 2.5899 THz. The proposed SFEM is an effective method to propagate uncertainty and analyze the impacts of uncertainty in the carbon atomic interactions of graphene. The work in this paper provides an important supplement to the atomic interaction modeling in nanomaterials.  相似文献   
156.
157.
To improve transportation efficiency, a supercritical CO2 pipeline is the best choice for large-scale and long-distance transportation inshore and offshore. However, corrosion of the pipe wall will occur as a result of the presence of free water and other impurities present during CO2 capture. Defects caused by corrosion can reduce pipe strength and result in pipe failure. In this paper, the burst pressure of subsea supercritical CO2 pipelines under high pressure is investigated. First, a mechanical model of corroded CO2 pipelines is established. Then, using the unified strength theory (UST), a new burst pressure equation for subsea supercritical CO2 pipelines is derived. Next, analysis of the material’s intermediate principal stress parameters is conducted. Lastly, the accuracy of the burst pressure equation of subsea supercritical CO2 pipelines is proven to meet the engineering requirement by experimental data. The results indicate that the parameter b of UST plays a significant role in determining burst pressure of pipelines. The study can provide a theoretical basis and reference for the design of subsea supercritical CO2 pipelines.  相似文献   
158.
159.
Andrographolide (1), an active constituent of Andrographis paniculata, decreased tumor necrosis factor-α (TNF-α)-induced intercellular adhesion molecule-1 (ICAM-1) expression and adhesion of HL-60 cells onto human umbilical vein endothelial cells (HUVEC), which are associated with inflammatory diseases. Moreover, 1 abolished TNF-α-induced Akt phosphorylation. Transfection of an activated Akt1 cDNA vector increased Akt phosphorylation and ICAM-1 expression like TNF-α. In addition, 1 and LY294002 blocked TNF-α-induced IκB-α degradation and nuclear p65 protein accumulation, as well as the DNA-binding activity of NF-κB. Compound 1 exhibits anti-inflammatory properties through the inhibition of TNF-α-induced ICAM-1 expression. The anti-inflammatory activity of 1 may be associated with the inhibition of the PI3K/Akt pathway and downstream target NF-κB activation in HUVEC cells.  相似文献   
160.
柴胡加龙骨牡蛎汤对抑郁模型大鼠脑内单胺递质的影响   总被引:13,自引:0,他引:13  
目的:探讨柴胡加龙骨牡蛎汤抗抑郁作用的机理。方法:雄性SD大鼠用孤养加慢性应激造成抑郁模型,用高效液相-电化学法测定大鼠脑内单胺类神经递质及其主要代谢产物的含量。结果:模型组大鼠下丘脑、纹状体、边缘区和大脑皮层单胺类神经递质及其代谢产物的含量明显减少,而柴胡龙牡汤可使抑郁大鼠下丘脑、纹状体、边缘区和大脑皮层NA、DA、DOPAC、5-HTT含量普遍增加,纹状体和边缘区5-HT水平显升高。结论:柴胡龙牡汤的抗抑郁作用可能与增加脑内单胺类神经递质的含量有关。  相似文献   
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