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41.
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目的建立完善的鼓膜-听骨链模型,利用有限元初步探讨镫骨前、后脚骨质缺损对听力传导的影响。方法实验数据源于对一名无中耳病史的成年男性左侧颞骨进行Micro-CT扫描,在医学影像处理软件Mimics上进行三维重建,利用Geomagic形成需要的曲面,最后在SolidWorks上将成型的鼓膜-听骨链模型进行切割组装,建立正常听骨链模型以及镫骨前、后脚骨质缺损模型,利用模型分析骨质缺损对听力传导的影响。结果建立的鼓膜-听骨链模型镫骨足板频振曲线符合相关文献报道,在镫骨前、后脚骨质缺损病理模型下,曲线与正常中耳模型曲线接近。结论利用多软件综合处理,可建立可信度较高的中耳听骨链模型;有限元模拟分析结果显示,镫骨前、后脚缺损部分骨质,未对听力传导产生明显影响。  相似文献   
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The term myelodysplastic/myeloproliferative neoplasm (MDS/MPN) refers to a group of clonal hematopoietic neoplasms with overlapping clinical, morphologic and genetic myelodysplastic and myeloproliferative features observed at the time of first presentation. Impaired hematopoiesis morphologically associated with evidence of myelodysplasia manifests clinically with cytopenia/s. Simultaneously, myeloproliferation is seen within the bone marrow and leads to cytosis in the peripheral blood.The diagnostic category of MDS/MPN encompasses a heterogeneous group of diseases which share similarities among them, but at the same time have distinct clinical and pathologic features and eventually diverse prognosis; such differences justify their separation in a classification scheme.In the era of genetic and genomic tests, their distinction from conventional myelodysplastic syndromes or myeloproliferative neoplasms still relies on close clinocopathological correlation, with evaluation of both peripheral blood and bone marrow samples being essential in this sense. A multiparametric integration of clinicopathologic data and cytogenetics and molecular genetics results is the preferred diagnostic approach.  相似文献   
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目的 探讨保留足趾的自体复合第2足趾关节移植治疗手指关节炎的临床疗效.方法 2016年2月至2018年6月,共收治创伤性手指关节炎9例,其中男7例,女2例;年龄19~53岁,平均31.7岁;示指3例,中指6例;掌指关节(MP)关节炎4例,近侧指骨间关节(PIP)关节炎5例;均为创伤后继发的手指关节炎.采用游离带血供的自体复合第2足趾跖趾或趾骨间关节移植进行治疗,同时将受区废弃关节(7例)或切取自体髂骨移植(2例)修复供区骨缺损保留足趾长度,供区创面均直接关闭.术后观察手指和足趾骨折愈合情况、外形、移植关节活动度(ROM)、术后供区愈合情况和行走功能及相关并发症.结果 本组术后9例移植关节全部成活,1例足部供区行髂骨植骨微型钢板固定,术后1周伤口不愈合,考虑为内固定物排异反应,予拆除钢板改克氏针交叉固定,2周后创口顺利愈合.术后随访6~30个月,平均16.3个月.手指骨折平均愈合时间7~10周,平均8.3周,手指外观及功能良好.移植后的MP活动度为50°~75°,平均65.3°,PIP活动度为10°~85°,平均60.6°.根据中华医学会手外科学分会上肢部分功能评定试用标准评价手指功能:优5例,良3例,可1例,优良率为88.9%.足趾骨折平均愈合时间9~12周,平均10.2周,所有患者足趾外形良好,行走功能正常.2例取髂骨患者供区仅残留一条线形瘢痕,无疼痛、麻木等不适.结论 游离带血供的自体复合第2足趾关节移植治疗手指关节炎,同时应用受区废弃关节或切取自体髂骨移植修复供区骨缺损保留足趾,不仅能恢复手指关节的正常结构,使关节具有良好的功能,而且能保留足趾外形与功能,减少供区损伤,具有良好的治疗效果.  相似文献   
46.
BackgroundConsidering the limitations in isolating Bone Marrow Mesenchymal Stem Cells (BMSCs), alternate sources of Mesenchymal Stem Cells (MSCs) are being intensely investigated. This study evaluated dental pulp MSCs (DP-MSCs) isolated from orthodontically extracted premolar teeth from a bone tissue engineering perspective.MethodsMSCs isolated from premolar teeth pulp were cultured and studied using BMSCs as the control. Flow cytometry analysis was performed for the positive and negative MSC markers. Multilineage differentiation focusing on bone regeneration was evaluated by specific growth induction culturing media and by alkaline phosphatase (ALP) activity. Data were compared by repeated measurement analysis of variance and Student's t-test at a p value <0.05.ResultsProliferation rate, population doubling time, and colony formation of DP-MSCs were significantly higher (p < 0.001) than BMSCs. More than 85% of DP-MSCs expressed CD44, CD73, CD90, CD105, and CD166. Negative reaction was found for CD11b CD33, CD34, and CD45. Positive reaction was displayed by 7.2% of cells for early MSC marker, Stro-1. Both the cell populations differentiated into adipogenic, osteogenic, and chondrogenic lineages, with adequate ALP expression.ConclusionBecause DP-MSCs from orthodontic premolars hold a neural crest/ectomesenchymal ancestry, its prudent growth characteristics and multilineage differentiation open up exciting options in craniofacial tissue engineering.  相似文献   
47.
目的:探讨补肾活血壮骨汤对椎体压缩性骨折患者的临床疗效及骨代谢的影响。方法:收集我院骨伤科收治的椎体压缩性骨折患者70例,随机分为试验组和对照组,各35例。两组患者均接受椎体成形术(Percutaneous Vertebroplasty,PVP),对照组术后予以阿法骨化醇软胶囊;试验组在对照组的基础上予以补肾活血壮骨汤。两组均以4周为一个疗效,连续服用3个疗程。比较两组患者视觉模拟评分法(Visual Analogue Scale,VAS)、椎体前壁高度(Anterior Vertebral Body Height,AVBH)、椎体后凸角度(Cobb)、骨密度(Bone Mineral Density,BMD)、血清骨钙素(BGP)、碱性磷酸酶(Alkaline Phosphatase,ALP)、I型前胶原氨基端肽(N-terminal Propeptide of Type I Procollagen,PINP)以及骨保护素(Osteoprotectin,OPG)水平。结果:治疗后两组VAS、Cobb、PINP低于治疗前,BGP、ALP、OPG、AVBH以及BMD高于治疗前(P<0.05);试验组VAS、Cobb、PINP低于对照组,BGP、ALP、OPG、AVBH以及BMD高于对照组(P<0.05)。结论:补肾活血壮骨汤能够显著缓解患者疼痛,促进骨折愈合,改善脊柱功能以及骨密度,其治疗机制可能与调节骨代谢水平具有相关性。  相似文献   
48.
BackgroundMedical and surgical interventions to prevent or reduce bone deformities and improve gait in children with cerebral palsy (CP) are based on empirical evidence that there is a relationship between bone deformities and gait deviations.Research questionWhat is the relationship between tibial-femoral bone morphology and kinematic gait variables in ambulant children with CP?MethodsA retrospective analysis was conducted on data from 121 children with uni- (n = 64, mean age 9.9 (SD 3.4) years) and bi- lateral (n = 57, mean age 10.4 (SD 3.6) years) CP who had undergone 3D gait analysis and biplanar X-rays (EOS® system). The limbs were split as DIP (the more impaired limb of children with bilateral CP), HEMI (the impaired limb of unilateral CP) and REF (the unimpaired limb of unilateral CP). Multi-variable Linear Regressions were performed between 23 kinematic variables, the Gait Deviation Index (GDI) and a model composed of nine 3D bone variables for each limb type.ResultsWhen the whole sample was pooled, 72% of R2 values were poor, 16% were fair, and 12% were moderate. Lower limb bone morphology models explained less than 1% of GDI variability. Correlations between tibial-femoral rotational parameters and hip rotation were mostly poor. Mean foot progression angle was the only kinematic parameter that was fairly to moderately correlated with bone variables in the 3 limb types. A tibial-femoral bone model explained 48% of the variability of mean foot progression angle in the REF limbs, 31% in the HEMI limbs and 25% in the DIP limbs.SignificanceTibial-femoral bone morphology was only weakly related to kinematic gait variables, in contrast with common clinical assumptions. These results suggest that factors other than bone morphology influence gait quality and thus a thorough clinical examination and gait analysis is required prior to making treatment decisions.  相似文献   
49.
如何对股骨转子间骨折、尤其是头颈骨块进行有效固定,进而稳定并支撑骨质疏松的骨折端,已成为当今创伤骨科研究的热点之一。为了减少固定失败率,临床上除了提高内固定的设计,应用骨增强材料提高固定的效果是另一个富有前景的研究领域。因此,本文围绕骨水泥增强材料的研究历史、材料特点、目前其生物力学和临床应用研究等方面进行综述,以提高对骨生物增强材料进行内固定的原理、手术技术和应用范围的认识,进而为其临床应用的选择提供帮助。  相似文献   
50.
PurposeThe purpose of this study was to develop predictive models to classify osteoporosis, osteopenia and normal patients using radiomics and machine learning approaches.Materials and methodsA total of 147 patients were included in this retrospective single-center study. There were 12 men and 135 women with a mean age of 56.88 ± 10.6 (SD) years (range: 28–87 years). For each patient, seven regions including four lumbar and three femoral including trochanteric, intertrochanteric and neck were segmented on bone mineral densitometry images and 54 texture features were extracted from the regions. The performance of four feature selection methods, including classifier attribute evaluation (CLAE), one rule attribute evaluation (ORAE), gain ratio attribute evaluation (GRAE) and principal components analysis (PRCA) along with four classification methods, including random forest (RF), random committee (RC), K-nearest neighbor (KN) and logit-boost (LB) were evaluated. Four classification categories, including osteopenia vs. normal, osteoporosis vs. normal, osteopenia vs. osteoporosis and osteoporosis + osteopenia vs. osteoporosis were examined for the defined seven regions. The classification model performances were evaluated using the area under the receiver operator characteristic curve (AUC).ResultsThe AUC values ranged from 0.50 to 0.78. The combination of methods RF + CLAE, RF + ORAE and RC + ORAE yielded highest performance (AUC = 0.78) in discriminating between osteoporosis and normal state in the trochanteric region. The combinations of RF + PRCA and LB + PRCA had the highest performance (AUC = 0.76) in discriminating between osteoporosis and normal state in the neck region.ConclusionThe machine learning radiomic approach can be considered as a new method for bone mineral deficiency disease classification using bone mineral densitometry image features.  相似文献   
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