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31.
一体化假肢是以聚合物为材料从接受腔到假腿一体成型的新型下肢假肢,它比传统型假肢更经济、美观、轻便,具有较大的应用前景。目前的相关研究主要集中在设计与制作及少量的临床研究方面。由于一体化假肢与传统型假肢在结构上的差异,有必要对其进行应力分析。本研究的目的是开展内骨架一体化假肢的生物力学研究,本研究基于内骨架一体化小腿假肢的真实几何构型,建立三维有限元模型,计算该模型在模拟Heel OH步态时相的载荷作用下的应力分布;在保持该模型的几何形状不变的情况下,建立了三个不同壁面厚度的一体化小腿假肢的有限元模型,分析壁面厚度对一体化小腿假肢应力分布的影响;通过分别赋予模型四种不同高分子聚合物的材料力学特性值,分析不同材料的一体化假肢的应力分布特点;分别对模型施加与正常步态的五个典型时相对应的载荷,分析一体化小腿假肢在各步态时相的应力分布特点。本研究结果对一体化假肢设计有指导价值。 相似文献
32.
A new noninvasive method of measuring the structure and the electrical properties of bilayered biological tissues was evaluated as a potentially useful diagnostic means for detecting changes in subcutaneous tissues. First, the input impedance of an open-ended coaxial probe radiating into a bilayered model was calculated using a full-wave method, the results showed that the evanescen higher order modes do not have a significant influence on the reflection coefficient of muscle layer surface. Then, it was clearly proven that the phase shift and the modulus of the reflection coefficient of muscle layer surface depending on the frequency are useful to estimate the thickness of fat layer and the electrical properties of muscle respectively. The experimental results showed an excellent agreement with the theoretical relationship between the phase shift and the thickness. The sensitivity of estimation of the electrical properties of muscle was shown to be not enough for differentiating between normal and diseased deep tissue because of noises from the experimental systems. 相似文献
33.
C. R. Kumana I. J. Lauder M. Chan W. Ko H. J. Lin 《European journal of clinical pharmacology》1987,32(2):211-215
Summary We have compared diazepam pharmacokinetics in 16 Chinese and 18 white Caucasian healthy male volunteers, resident in Hong Kong and have correlated them with physical attributes. Serum concentrations of diazepam and desmethyldiazepam were measured in venous blood by an enzyme-linked immunoassay (0–3 h samples) and HPLC (3–72 h samples). Pharmacokinetic parameters were derived assuming a two compartment model, distribution phase <6 h, and 100% oral systemic availability. Compared with the Chinese the white Caucasians were older, heavier, taller, and fatter, as judged by skin fold thickness (SFT) and total body weight to Ideal body weight (TBW/IBW) ratio; respective mean differences being 16%, 27%, 4%, 26%, and 15% (p<0.05). Mean diazepam apparent volume of distribution (V) and V/IBW were larger in the white Caucasians (52% & 39% respectively, p=0.002). SFT and TBW/IBW ratio yielded the best correlations with V, V/TBW and V/IBW (0.50–0.75, p<0.05). Obesity indices contributed most to the overall regressions (R2 up to 0.52), and for V there was a further small effect (2%, partial F test) due to ethnic group, possibly reflecting stature. Mean peak diazepam concentration (Cmax) was similar in both ethnic groups. Time to Cmax (tmax) was more often prolonged in the Chinese (X
2 test, p=0.01). Body fat and stature may thus account for these inter-ethnic differences in the apparent volume of distribution of diazepam, a highly lipid-soluble drug. 相似文献
34.
目的:探究磁共振成像(MRI)对前置胎盘的诊断价值。方法:选取2018年1月至2021年6月新疆生产建设兵团医院接诊的基于临床症状诊断为前置胎盘孕妇79例,所有孕妇均在手术前行盆腔MRI扫描,观察胎盘厚度、宫颈长度、胎盘T2低信号带、宫颈边缘窦、膀胱隆起、子宫肌层变薄信号,分析上述MRI征象、指标对前置胎盘的诊断价值。结果:79例孕妇中,最终经手术病理证实为前置胎盘的患者52例。MRI征象中的胎盘T2低信号带、宫颈边缘窦、膀胱隆起、子宫肌层变薄均可有效诊断前置胎盘(P <0.05);检出率由高到低依次为:胎盘T2低信号带>宫颈边缘窦>子宫肌层变薄>膀胱隆起;胎盘厚度≥10 mm时,胎盘厚度与前置胎盘呈正相关(r=0.852,P=0.016);胎盘厚度<10 mm时,胎盘厚度与前置胎盘无相关性(r=0.201,P=0.052)。宫颈长度≥30 mm时,宫颈长度与前置胎盘无相关性(r=0.376,P=0.071);宫颈长度<30 mm时,宫颈长度与前置胎盘呈负相关(r=–0.721,P=0.036)。结论:MRI征象(胎盘T2低信号带、宫颈边缘窦、膀胱隆... 相似文献
35.
Emrah Caliskan Salih Suha Koparal Volkan Igdir Emre Alp Ozgur Dogan 《Foot and Ankle Surgery》2021,27(4):457-462
BackgroundThe measurement of plantar fascia thickness with ultrasonography can be used for both for diagnosis and as a response-to-treatment parameter in plantar fasciitis. Furthermore, with the recent studies, red cell distribution width may be used as an inflammatory marker. Aim of this study is to investigate the association of red cell distribution width and ultrasonography on diagnosis and monitoring of treatment in patients with plantar fasciitis.MethodsClinically diagnosed 102 patients with plantar fasciitis between the dates January 2016 to July 2018 were analysed. Hemogram, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and plantar fascial ultrasonography were obtained on initial evaluation and in 1 month, 2 months and 3 months of the standard nonoperative treatment; American Orthopaedic Foot & Ankle Hindfoot Score (AOFAS) and Visual Analog Scale (VAS) scores were recorded. Posthoc and multivariate logistic regression analysis were used for statistical analysis on SPSS 21.0.ResultsRed cell distribution width was correlated with plantar fascia thickness by the end of the 1 month (r = 0.26, P = .013). Female sex, BMI over 30 kg/m2, higher red cell distribution width and higher plantar fascia thickness were associated with plantar fasciitis on initial evaluation. Higher red cell distribution width together with higher plantar fascia thickness were also found to be a risk factor for both on initial evaluation and 1 month after treatment in plantar fasciitis.ConclusionThis study shows that association of red cell distribution width and plantar fascia thickness can be not only a diagnostic predictor but also an indicator of treatment response in plantar fasciitis.Level of clinical evidenceLevel IV 相似文献
36.
Milutin Bulajic Salvatore Francesco Vadal di Prampero Ivo Boškoski Guido Costamagna 《World journal of gastrointestinal surgery》2021,13(12):1584-1596
Weight regain following primary bariatric surgery occurs in a significant proportion of patients and is attributed to epidemiological, anatomical and metabolic factors. Surgical revision of these patients has significant risks and limited benefits. Endoscopic revisions that reduce gastric pouch size and diameter of the gastrojejunal anastomosis may offer an effective, safe, less invasive and even reproducible treatment. We herein discuss the indication, selection and feasibility of different endoscopic techniques that could be used in the management of weight regain following primary bariatric surgery. Future research could optimize a personalized approach not only in the endoscopic management but also in combination with other therapeutic modalities for weight regain after bariatric surgery. 相似文献
37.
目的:评价武警阅队成员体脂成分现状,为科学选兵,合理制定训练计划和正确指导膳食营养提供资料,方法:以皮褶厚度测量法推算体脂指标。结果:武警甘部战士,学员在多项体脂指标方面都优于同龄地方大学生和通讯兵某部战士,对体脂百分率评价,男性均值尚属正常,肥胖占2.2%;女性均值超标了2.66%,肥胖占12.4%,结论:武警某部战士、学员体脂成分现尚好,但应注意严格选兵标准,科学调整膳食,加大耐力性训练力度。 相似文献
38.
YANG Zhikuan DU Shuhua Department of Ophthalmology Tongji Hospital Tongji Medical University Wuhan 《华中科技大学学报(医学英德文版)》1999,19(3):246-248
Manyophthalmologicaldiseasesareinvolvedintheretinalthickness.Recentyears,retinalthicknessanalyzer(RTA)hasbeendevelopedtobeusedinvivotomeasuretheposteriorpoleretinalthicknessandtodiagnoseinsuchdiseasesasdiabetesmellitus,glaucoma,maculahole,etc[1].Thes… 相似文献
39.
Novel imaging techniques for diabetic macular edema 总被引:2,自引:0,他引:2
Lobo C Bernardes R Faria de Abreu JR Cunha-Vaz JG 《Documenta ophthalmologica. Advances in ophthalmology》1999,97(3-4):341-347
Retinal edema should be defined as any increase of water of the retinal tissue resulting in an increase in its volume. It
may be of cytotoxic or vasogenic origin. Development of vasogenic macular edema is dependent on a series of factors such as
blood pressure, blood-retinal barrier permeability, retinal cell damage, retinal tissue osmotic pressure and retinal tissue
compliance. Objective measurements of retinal thickness are now possible using the Retinal Thickness Analyser. Localised measurements
of blood-retinal barrier permeability may also be obtained using the Retinal Leakage Analyser, a modified confocal scanning
laser fluorometer, while obtaining simultaneously angiographic images of the choroid and retina. These new imaging techniques
show that cytotoxic and vasogenic retinal edema may occur independently in the early stages of diabetic retinopathy. These
findings offer new perpectives for designing novel therapeutic strategies.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
40.
准分子激光原位角膜磨镶术后屈光回退与术中角膜床厚度的关系 总被引:6,自引:2,他引:4
目的 探讨准分子激光原位角膜磨镶术(excimer laser insitu keratomileusis LASIK) 矫治高度近视后屈光回退与术中角膜床厚度的关系。方法 对476 例938 只眼在我院接受Lasik 治疗的患者中,发生屈光回退的病例96 例,189 只眼与未发生屈光回退的病例380 例749 只眼术中角膜床厚度及术前、术后1 w k 、1 、3 、6 m o 屈光状态的资料进行对比分析。结果 有屈光回退眼组比无屈光回退眼组平均角膜床厚度小;屈光回退眼组屈光回退程度( 术后6 mo 时) 与角膜床厚度呈负相关系,上述结果经统计学检验均有显著性差异( P < 001) ;有屈光回退眼组术后早期(1 wk) 屈光状态略成过矫,但其后屈光回退程度在0 .5a 内呈加重趋势。结论 高度近视准分子激光原位角膜磨镶术中的角膜床厚度是影响术后屈光稳定性的重要因素 相似文献