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51.
Neural and musculoskeletal contributions to the development of stance balance control in typical children and in children with cerebral palsy 总被引:3,自引:0,他引:3
Studies on the development of automatic postural responses in both typically developing children and children with cerebral palsy were performed. With the appearance of "pull-to-stand" behavior, typically developing children first began to show muscle responses to platform movements in mainly the ankle muscles. With increased development, additional agonist muscles were added to the response pattern and a consistent distal to proximal sequence began to emerge. Well-organized responses were seen with the onset of independent stance and walking, along with the reduction of antagonist muscle co-activation. The older children with cerebral palsy who were pre-walkers had immature muscle activation patterns like those seen in the typically developing children at the pull-to- stand stage of development. These included disorganized muscle responses and increased frequency of coactivation of both proximal–distal and agonist–antagonist muscles. In order to determine if musculoskeletal constraints contributed to these response patterns, normal children were asked to stand in a crouched posture similar to that of children with CP. This caused postural muscle response patterns to more closely approximate those of children with spastic diplegia. 相似文献
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PR Hunziker S Smith M Scherrer-Crosbie N Liel-Cohen RA Levine R Nesbitt SA Benton MH Picard 《Circulation》1999,99(5):1-6
Background--Currently, the reporting and archiving of echocardiographic data suffer from the difficulty of representing heart motion on printable 2-dimensional (2D) media. Methods and Results--We studied the capability of holography to integrate motion into 2D echocardiographic prints. Images of normal human hearts and of a variety of mitral valve function abnormalities (mitral valve prolapse, systolic anterior motion of the mitral leaflets, and obstruction of the mitral valve by a myxoma) were acquired digitally on standard echocardiographic machines. Images were processed into a data format suitable for holographic printing. Angularly multiplexed holograms were then printed on a prototype holographic "laser" printer, with integration of time in vertical parallax, so that heart motion became visible when the hologram was tilted up and down. The resulting holograms displayed the anatomy with the same resolution as the original acquisition and allowed detailed study of valve motion with side-by-side comparison of normal and abnormal findings. Comparison of standard echocardiographic measurements in original echo frames and corresponding hologram views showed an excellent correlation of both methods (P<0.0001, r2=0.979, mean bias=2.76 mm). In this feasibility study, both 2D and 3D holographic images were produced. The equipment needed to view these holograms consists of only a simple point-light source. Conclusions--Holographic representation of myocardial and valve motion from echocardiographic data is feasible and allows the printing on a 2D medium of the complete heart cycle. Combined with the recent development of online holographic printing, this novel technique has the potential to improve reporting, visualization, and archiving of echocardiographic imaging. 相似文献
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保证输血时血清学方面的安全,首要的是对受血者与献血者ABO血型定型,血清学检查通常分两个步骤.正定型通常使用鼠源单克隆抗体检测红细胞表面是否存在A或B抗原.互补的实验即反定型,利用当红细胞上缺乏A或B抗原时,人群可天然产生相对应的抗体的原理,检测血清中是否存在抗-A或者抗-B抗体.确定了受血者红细胞表面的ABO抗原以及血浆中的抗体,便能确定血型,为其提供相合的血液. 相似文献
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目的:实验以移植后3个月、6个月时间超声心动图客观指标评估了自体干细胞冠状动脉内移植治疗老龄心肌梗死后心力衰竭的效果和安全性。方法:选择2004—06/2006—06江苏省苏北人民医院心内科自愿接受干细胞移植的7例心肌梗死后心力衰竭患者,平均年龄69岁,心功能Ⅲ-Ⅳ级,左室射血分数〈50%。药物治疗基础上加用自体干细胞冠状动脉内移植治疗的方法,其中2例骨髓干细胞在体外扩增后获得,5例经粒细胞集落刺激因子皮下注射动员自体骨髓干细胞后分离外周血获得干细胞悬液。将采集的干细胞悬液经0ver-the-wire球囊导管中心腔注入梗死相关动脉。观察自体干细胞动员,培养,采集和回输过程中的不良反应。在移植前、移植后3月、6月应用超声心动图评价左室形态和心功能变化,室壁运动积分指数及6min步行距离。结果:7例患者均进入结果分析。移植3个月后,心功能得到改善,超声心动图检查左室收缩期内径及射血分数变化不大,6min步行距离有所提高,但差异无显著性(P〉0.05)。移植6个月后,患者心功能明显改善,超声心动图检查左室收缩期内径及射血分数和室壁运动积分均有明显提高(P〈0.05),6min步行距离也有明显提高(P〈0.05)。整个过程中未出现严重并发症。结论:自体干细胞冠状动脉内移植治疗老龄心肌梗死后心力衰竭,6个月时超声心动图客观指标评估能够改善患者心功能,且安全。 相似文献