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101.
目的对组织工程化骨形成蛋白-脱钙骨基质颗粒-骨水泥复合材料进行弹性模量测定并探讨其临床意义。方法提取牛骨形成蛋白(bBMP)并进行成骨诱导活性测定,制备人的异体脱钙骨基质颗粒(DBM),将bBMP与DBM以1:25的质量比复合后,再与骨水泥(BC)按0:10,4:6,5:5,6:4和7.5:2.5的质量比进行复合,对所得的骨形成蛋白-脱钙骨基质颗粒-骨水泥复合材料进行弹性模量测定,并与正常人成年男性的股骨、股骨下端松质骨的弹性模量相比较。结果对测定结果进行统计学分析,含bBMP-DBM复合物75%的复合材料的弹性模量与正常成年男性股骨下端松质骨的弹性模量差异无显著性意义,P<0.01,其余各组两两比较均差异有显著性意义,P>0.01。结论含bBMP-DBM复合物75%的复合材料与成年男性股骨下端松质骨的弹性模量相接近,用其修复靠近关节面附近骨缺损可有效的防止关节的退行性变。 相似文献
102.
T. Kangro T. Jonason E. Henriksen I. Ringqvist 《Clinical physiology and functional imaging》1997,17(6):579-590
Doppler indices of left ventricular diastolic filling are associated with various cardiac and extracardiac factors. Afterload is one of the extracardiac factors influencing left ventricular diastolic filling. The distensibility of the great arteries is one of the components of afterload. In this study, the relation between Doppler indices of left ventricular filling and the distensibility of the common carotid arteries was investigated. We studied 237 subjects at 50 years of age with Doppler echocardiography and ultrasound examination of the common carotid arteries. The following Doppler indices of left ventricular filling were studied: peak early diastolic velocity E-wave, peak atrial diastolic velocity A-wave and early to atrial peak velocity ratio, E/A. Carotid arterial characteristics were: distensibility coefficient, carotid arterial diameter change in systole and fractional change in the carotid arterial diameter. The relation between Doppler indices of left ventricular filling and carotid arterial characteristics was assessed by univariate and multivariate regression analysis. There was a significant univariate, positive association between E/A ratio and carotid arterial distensibility (r = 0·27, P<0·001), carotid arterial systolic diameter change (r = 0·19, P<0·005) and fractional change of the carotid arterial diameter (r = 0·20, P<0·005). In multivariate analysis, E/A ratio was independently associated with carotid arterial distensibility (P<0·005), after adjusting for heart rate, body mass index and gender. Decreased carotid arterial distensibility was associated with a reduction in E/A ratio, suggesting that arterial distensibility may have an effect on left ventricular diastolic filling or that changes in the arterial elastic properties are associated with corresponding structural changes in the left ventricle. 相似文献
103.
Silk fibroin scaffolds with muscle‐like elasticity support in vitro differentiation of human skeletal muscle cells
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Vishal Chaturvedi Deboki Naskar Beverley F. Kinnear Elizabeth Grenik Danielle E. Dye Miranda D. Grounds Subhas C. Kundu Deirdre R. Coombe 《Journal of tissue engineering and regenerative medicine》2017,11(11):3178-3192
Human adult skeletal muscle has a limited ability to regenerate after injury and therapeutic options for volumetric muscle loss are few. Technologies to enhance regeneration of tissues generally rely upon bioscaffolds to mimic aspects of the tissue extracellular matrix (ECM). In the present study, silk fibroins from four Lepidoptera (silkworm) species engineered into three‐dimensional scaffolds were examined for their ability to support the differentiation of primary human skeletal muscle myoblasts. Human skeletal muscle myoblasts (HSMMs) adhered, spread and deposited extensive ECM on all the scaffolds, but immunofluorescence and quantitative polymerase chain reaction analysis of gene expression revealed that myotube formation occurred differently on the various scaffolds. Bombyx mori fibroin scaffolds supported formation of long, well‐aligned myotubes, whereas on Antheraea mylitta fibroin scaffolds the myotubes were thicker and shorter. Myotubes were oriented in two perpendicular layers on Antheraea assamensis scaffolds, and scaffolds of Philosamia/Samia ricini (S. ricini) fibroin poorly supported myotube formation. These differences were not caused by fibroin composition per se, as HSMMs adhered to, proliferated on and formed striated myotubes on all four fibroins presented as two‐dimensional fibroin films. The Young's modulus of A. mylitta and B. mori scaffolds mimicked that of normal skeletal muscle, but A. assamensis and S. ricini scaffolds were more flexible. The present study demonstrates that although myoblasts deposit matrix onto fibroin scaffolds and create a permissive environment for cell proliferation, a scaffold elasticity resembling that of normal muscle is required for optimal myotube length, alignment, and maturation. © 2016 The Authors Journal of Tissue Engineering and Regenerative Medicine Published by John Wiley & Sons Ltd. StartCopTextStartCopText© 2016 The Authors Journal of Tissue Engineering and Regenerative Medicine Published by John Wiley & Sons Ltd. 相似文献
104.
Aims The addiction sciences are intrinsically multi‐disciplinary, and economics is among the disciplines that offer useful perspectives on the complex behaviors surrounding substance abuse. This paper summarizes contributions economics has made in the past and could make in the future towards understanding how illegal markets operate, how prices affect use, how use generates various consequences, and how policy shapes all three. Methods Review of literature, concentrating on illegal drugs as insights concerning markets are particularly salient, although we also mention relevant studies from the alcohol and tobacco fields. Findings and Conclusions Economics offers tools and topical expertise that usefully complement other disciplines associated traditionally with the addiction sciences. Its value goes far beyond the ability to monetize non‐monetary outcomes or to calculate a cost‐benefit ratio. 相似文献
105.
目的 应用血管回声跟踪技术检测颈动脉弹性变化及二维超声观察主动脉瓣钙化,研究二者与冠状动脉粥样硬化关系及预测价值.方法 应用血管回声跟踪技术对196例行冠脉造影(CAG)受检者进行颈总动脉检查,记录血管弹性指标,包括弹性系数(Ep)、僵硬度(β)、顺应性(AC)、脉搏波传导速度(PWVβ).同时二维超声观察主动脉瓣有无钙化,并将上述结果与CAG结果进行t检验.结果 颈动脉弹性减退与冠脉病变的相关性:β、Ep与CHD呈正相关(r=0.281,r=0.253,P<0.01,P<0.05),AVC与CHD呈正相关(r=0.173,P<0.05).结论 颈动脉弹性减退及主动脉瓣钙化是冠心病的高危因素,对冠心病有较大的预测价值.
Abstract:
Objective To study the relationship and predictive value of variation of carotid artery elasticity detected by echotracking (ET) technique and aortic valve calcification detected by two - dimensional ultrasonography with coronary heart disease (CHD). Methods The carotid artery elasticity of 196 cases who underwent coronary angiography(CAG) for suspected CHD were detected by echotracking (ET) technique and the indicators of artery elasticity were recorded, which includes elasticity modulus ( Ep), stiffness parameter ( β ), arterial compliance ( AC ) and pulse wave velocity ( PWVβ ).And aortic valve calcification was detected by two - dimensional ultrasonography, T test was carried out between the results of ultrasound examination and CAG. Results The indicators β, EP of carotid artery elasticity were positively correlated with the extent of CHD( r =0. 281,0.253; P < 0.01, < 0.05). In the mean time, positive correlation between aortic valve calcification and the extent of CHD was found (r = 0. 173, P < 0.05). Conclusions Carotid artery elasticity reducing and AVC are high risk factors of CHD and have great values in predicting CHD. 相似文献
106.
目的:探讨E-Tracking技术在评价妊娠期高血压疾病患者颈动脉弹性功能中的应用价值。方法:对29例妊娠晚期妊娠期高血压疾病患者(疾病组)和32例正常妊娠晚期妇女(对照组)进行双侧颈总动脉血管弹性指标(弹性模量Ep、僵硬度β、顺应性AC、脉搏波传导速度PWVβ及膨大指数AI)及内中膜厚度(IMT)的测量,并进行统计学分析。结果:疾病组双侧颈总动脉Ep、β、PWVβ及AI较对照组升高,疾病组AC较对照组减低,具有极显著性差异(P〈0.01);两组间颈总动脉内中膜厚度无显著性差异(P〉0.05)。结论:血管回声跟踪技术在评价妊娠期高血压疾病血管弹性方面具有一定价值。 相似文献
107.
目的应用声触诊组织定量技术探讨健康志愿者胰腺的正常弹性值。方法 210名健康志愿者分成三组:青年组(<30岁)、中年组(30~50)岁、老年组(>50岁),使用具有VTQ技术的超声仪器对其进行检查得到剪切波速度值(shear wave velocity,SWV)。结果胰头及胰体平均SWV与年龄、身高、体质量、腰围、BMI、胰头厚度、胰体厚度比较及相关性分析均无显著性差异(P>0.05);青年组、中年组、老年组健康志愿者胰头SWV平均值分别是1.13±0.24 m/s、1.15±0.23 m/s、1.08±0.22 m/s,而胰体SWV平均值分别为1.17±0.19 m/s、1.27±0.20 m/s、1.22±0.20 m/s,不同年龄组之间比较无显著性差异(P>0.05)。结论声触诊组织定量技术是测量胰腺弹性定量的一种新方法,需要进一步的研究为无创性诊断胰腺疾病奠定基础。 相似文献
108.
目的 研究高脂血症患者内皮功能异常、早期动脉弹性改变及阿托伐他汀对这些改变的影响.方法 选择未曾治疗的高脂血症患者40例作为研究组,健康体检者30例为对照组,应用在血管回声跟踪技术(eTRACKING)基础上实现的血流介导血管舒张检测技术(FMD)评估右肱动脉硬化参数及血管舒张参数,包括压力应变弹性系数(Ep)、硬度指数(β)、顺应性(AC)及收缩期血流介导血管舒张( FMDs)、舒张期血流介导血管舒张(FMDd);研究组给予阿托伐他汀20 mg口服,12周后复查总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)及上述参数,并进行统计学分析.结果 研究组β、Ep均较对照组明显升高(均P<0.001),而AC、FMDs、FMDd较对照组明显降低(均P<0.001);研究组治疗前后比较:TC、LDL-C、β、Ep降低,AC、FMDs、FMDd升高并有统计学意义(均P<0.001).结论 高脂血症患者在动脉内膜出现异常改变之前已出现内皮功能损伤及血管早期硬化改变,而阿托伐他汀干预能逆转这些改变. 相似文献
109.
Wang JM Huang YJ Wang Y Xu MG Wang LC Wang SM Tao J 《American journal of hypertension》2007,20(9):957-964
BACKGROUND: Impaired artery elasticity has been found in various pathological conditions related to endothelial dysfunction. Recently, CD31+/CD42- microparticles (MPs) emerged as a marker of endothelial injury. Whether CD31+/CD42- MPs, generated under physiological conditions, are correlated with artery properties has not been reported. METHODS: We evaluated brachia-ankle pulse-wave velocity (baPWV) (n = 76) and C1 large-artery and C2 small-artery elasticity indices (n = 56), using noninvasive devices for pulse-wave analysis in a group of healthy persons. The number of circulating CD31+/CD427- MPs (n = 76) was measured by flow cytometric analysis. RESULTS: Circulating CD31+/CD42- MPs were positively correlated with values of baPWV (r = 0.371, P = .008) and with C1 large-artery and C2 small-artery elasticity indices (r = -0.294, P = .037; and r = -0.310, P = .027, respectively). Multivariate analysis identified CD31+/CD42- MPs as potent contributors to the development of impaired systemic artery elasticity. CONCLUSIONS: The level of circulating CD31+/CD42- MPs, an important biomarker of dysfunctional endothelium and vascular injury, is closely associated with impaired systemic artery elasticity in healthy subjects. The present study suggests that CD31+/CD42- MPs may be a novel surrogate marker for the clinical evaluation of vascular damage. 相似文献
110.
H. Sumino S. Ichikawa S. Kasama T. Takahashi H. Kumakura Y. Takayama T. Kanda M. Murakami M. Kurabayashi 《Maturitas》2009