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1.
目的探讨单侧外固定治疗重度Pilon骨折的临床疗效。方法回顾性分析2017年6月-2018年12月南京中大医院江北院区骨科收治的重度Pilon骨折患者100例,男性54例,女性46例;年龄18~65岁,平均35.5岁;Ruedi-AllgowerⅡ型39例,Ⅲ型61例。按照不同固定方法分为常规固定组和单侧外固定组,各50例,比较两组患者住院时间、完全负重下地时间、骨折愈合时间,评价治疗前及治疗后3个月踝关节活动度、踝关节功能恢复情况、疼痛程度,并统计患者的治疗效果及并发症发生情况。结果单侧外固定组住院时间、完全负重下地时间、骨折愈合时间分别为(16.50±1.50)d、(132.56±10.25)d、(14.16±0.69)周,均短于常规固定组(19.25±2.35)d、(198.65±16.58)d、(17.58±1.50)周(t/P=6.975/0.001、23.970/0.001、14.650/0.001)。治疗后3个月,单侧外固定组踝关节Mazur评分为(85.67±6.59)分,显著高于常规固定组(62.78±3.45)分,VAS评分为(2.23±0.36)分,低于常规固定组(4.59±0.89)分(t/P=21.760/0.001、17.380/0.001);单侧外固定组患者踝关节活动度分别为(17.29±0.16)°、(28.36±1.23)°、(19.68±0.16)°、(16.89±2.12)°,均高于常规固定组(10.62±1.25)°、(21.57±2.58)°、(14.36±1.62)°、(14.25±0.57)°(t/P=37.430/0.001、16.800/0.001、23.110/0.001、8.503/0.001)。单侧外固定组治疗优良率为90.00%,显著高于常规固定组74.00%(χ^2/P=4.336/0.037)。单侧外固定组总并发症发生率为4.00%,显著低于常规固定组的18.00%(χ^2/P=5.005/0.025)。结论单侧外固定支架治疗重度Pilon骨折可有效减轻患者疼痛症状,提高患者踝关节活动度,恢复患者功能,治疗效果显著,安全性较高。  相似文献   
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Purpose: To study, with computational models, the utility of power modulation to reduce tissue temperature heterogeneity for variable nanoparticle distributions in magnetic nanoparticle hyperthermia.

Methods: Tumour and surrounding tissue were modeled by elliptical two- and three-dimensional computational phantoms having six different nanoparticle distributions. Nanoparticles were modeled as point heat sources having amplitude-dependent loss power. The total number of nanoparticles was fixed, and their spatial distribution and heat output were varied. Heat transfer was computed by solving the Pennes’ bioheat equation using finite element methods (FEM) with temperature-dependent blood perfusion. Local temperature was regulated using a proportional-integral-derivative (PID) controller. Tissue temperature, thermal dose and tissue damage were calculated. The required minimum thermal dose delivered to the tumor was kept constant, and heating power was adjusted for comparison of both the heating methods.

Results: Modulated power heating produced lower and more homogeneous temperature distributions than did constant power heating for all studied nanoparticle distributions. For a concentrated nanoparticle distribution, located off-center within the tumor, the maximum temperatures inside the tumor were 16% lower for modulated power heating when compared to constant power heating. This resulted in less damage to surrounding normal tissue. Modulated power heating reached target thermal doses up to nine-fold more rapidly when compared to constant power heating.

Conclusions: Controlling the temperature at the tumor-healthy tissue boundary by modulating the heating power of magnetic nanoparticles demonstrably compensates for a variable nanoparticle distribution to deliver effective treatment.  相似文献   

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ObjectiveMultiple treatment options for acetabular fractures in geriatric patients exist. However, no large-scale studies have reported the outcomes of acute total hip arthroplasty (THA) in this patient population. We systematically evaluated all available evidence to characterize clinical outcomes, complications, and revisions of acute THA for acetabular fractures in geriatric patients.MethodsMeta-analysis of 21 studies of 430 acetabular fractures with mean follow-up of 44 months (range, 17−97 months). Two independent researchers searched and evaluated the databases of Ovid, Embase, and United States National Library of Medicine using a Boolean search string up to December 2019. Population demographics and complications, including presence of heterotopic ossification (HO), dislocation, infection, revision rate, neurological deficits, and venous thromboembolic event (VTE), were recorded and analyzed.ResultsWeighted mean Harris Hip Score was 83.3 points, and 20% of the patients had reported complications. The most common complication was HO, with a rate of 19.5%. Brooker grade III and IV HO rates were lower at 6.8%. Hip dislocation occurred at a rate of 6.1%, 4.1% of patients developed VTE, deep infection occurred in 3.8%, and neurological complications occurred in 1.9%. Although the revision rate was described in most studies, we were unable to perform a survival analysis because the time to each revision was described in only a few studies. The revision rate was 4.3%.ConclusionsAcute THA is a viable option for treatment of acetabular fracture and can result in acceptable clinical outcomes and survivorship rates in older patients but with an associated complication rate of approximately 20%. Considering the limited treatment options, THA might be a viable alternative for appropriately selected patients.  相似文献   
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The aim of the study was to investigate whether hypothermic oxygenated liver perfusion after cold liver preservation resuscitated metabolic parameters and whether this treatment had a benefit for liver viability upon reperfusion.
We preserved rat livers either by cold storage (UW) for 10 h, or by perfusion for 3 h (oxygenated modified UW) after 10 h cold storage. We assessed viability of livers after preservation and after ischemic rewarming + normothermic reperfusion ex vivo . Ten hour cold storage reduced mitochondrial cytochrome oxidase and metabolically depleted the livers. Oxygenated perfusion after cold storage resulted in uploaded cellular energy charge and oxidized mitochondrial cytochrome oxidase. Reperfusion after 10 h cold storage increased formation of superoxid anions, release of cytosolic LDH, lipid peroxidation, caspase activities and led to disruption of sinusoidal endothelial cells. In contrast, reperfusion after 10 h cold storage + 3 h hypothermic oxygenated perfusion resulted in no changes of lipid peroxidation, bile flow, energy charge, total glutathione, LDH release and of caspase activation, as compared to fresh resected livers.
This study demonstrates, that a metabolically depleted liver due to cold storage can be energy recharged by short-termed cold machine perfusion. The machine perfused graft exhibited improved viability and functional integrity.  相似文献   
7.
目的 探讨复杂跟骨骨折治疗方法及AO钢板内固定价值.方法 应用AO钢板治疗累及距下关节的跟骨骨折24例,术中注意关节面复位和Bohler角的恢复.结果 24例病人经12~24个月随访,按照Fernandez评定标准:24例跟骨SandersⅡ-Ⅳ型骨折病人有18足评为优良.结论 距下关节面的复位和Bohler角的恢复,牢固的内固定和术后足够长时间的负重限制是成功的关键.  相似文献   
8.
关节镜辅助下钢板内固定治疗关节内跟骨骨折   总被引:3,自引:1,他引:2  
[目的]探讨分析关节镜辅助下钢板内固定治疗关节内跟骨骨折的方法和疗效;[方法]对78位患者,86例累及关节面的跟骨骨折在关节镜辅助下行切开复位钢板内固定术,术后平均随访18个月(12~30个月),通过比较术前术后X线片和踝足功能的AOFAS评分对治疗效果作分析评价.[结果]86例关节内跟骨骨折术后X线示复位满意.与术前存在显著性差异(P〈0.01),AOFAS评分优良率91.86%.[结论]对于关节内跟骨骨折,采用关节镜辅助钢板内固定更加接近解剖复位,足部功能恢复满意且并发症少  相似文献   
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[目的]评价后路半椎体切除术治疗半椎体所致脊柱侧后凸畸形的临床效果。[方法]2000年5月~2005年11月,采用后路半椎体切除及矫形固定融合术治疗14例完全分节半椎体所致脊柱侧后凸畸形患者。年龄2.5~14.4岁,平均7.4岁,半椎体均为侧后方半椎体,其中胸椎7例,腰椎7例。[结果]手术时间2~7 h,平均4.7h,术中出血量150~2 500 m l,平均560 m。l固定节段2~8个椎体,平均3.5。术后随访6~36个月。平均15.6个月。术后站立位脊柱正侧位X线片示冠状面Cobb's角由术前46.2°矫正到17.3°,平均矫正率62.6%,矢状面Cobb's角由术前48.3°矫正至术后16.2°,平均矫正率68.7%。终末随访时冠状面Cobb's角平均21.7°,丢失4.4°,矢状面Cobb's角平均18.7°,丢失2.5°。围手术期并发症包括:伤口愈合不良2例,术中术后椎弓根螺钉切割椎体2例。[结论]后路半椎体切除可直接去除致畸因素,在冠状面及矢状面均获得良好的矫形效果,与前后路手术相比可缩短手术时间,减少创伤,适用于从胸段到腰段的半椎体畸形。  相似文献   
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