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目的探讨眼轮匝肌蒂颞部岛状皮瓣与颞浅动脉蒂反流轴型耳后岛状皮瓣在修复瘢痕性睑外翻中的应用,提高睑外翻矫正后所致皮肤缺损的美学修复效果。方法自1998年2月以来,对18例瘢痕性睑外翻,采用眼轮匝肌蒂颞部岛状皮瓣旋转180°移位修复13例,皮瓣最大面积2.7cm×3.6cm;采用颞浅动脉蒂反流轴型耳后岛状皮瓣经面部皮下隧道转移修复5例,皮瓣最大面积3.1cm×5.4cm。结果1例反流轴型耳后岛状皮瓣术后出现静脉回流障碍,经对症处理后仅皮瓣远端部分表皮坏死,Ⅱ期植皮后治愈,其余17例皮瓣完全成活。随访6个月,睑外翻矫正,皮瓣颜色、质地与眼周皮肤相近,供区瘢痕不明显。结论根据睑外翻程度,可制备颞部岛状皮瓣或耳后岛状皮瓣转移。前者适用于修复较小面积的皮肤缺损,后者适用于修复较大面积的皮肤缺损。  相似文献   
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作者通过对30例颅脑疾患冠状CT扫描资料进行研究,提出在一定情况下,在横断CT扫描的基础上,加用冠状CT扫描或冠矢重建图象,对病变的精确定位、病变的起源和发展方向以及病变与周围结构的关系等很有裨益。  相似文献   
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The torque-angular deformation in right axial rotation until failure of the ligamentous occipito-atlanto-axial complex subjected to variable loading rate (dynamic) axial torque was characterized using a biaxial MTS system. A special fixture and gear box that permitted right axial rotation of the specimen until failure without imposing any additional constraints were used to obtain the data. The specimens were divided into three groups and tested until failure at three different dynamic loading rates: 50, 100, and 400 degrees/s. A previous study by the authors provided data for quasi-static (4 degrees/s) loading conditions. The torque versus rotation curves can be divided into two straight regions and two transition zones. The plots clearly indicated that at loading rates higher than 4 degrees/s, the specimens became stiffer in the region of steadily increasing resistance prior to failure. The increase in stiffness was maximum at 100 degrees/s. The stiffness decreased somewhat at 400 degrees/s in comparison with 100 degrees/s, but this decrease was not significant. The resulting torque-right axial rotation curves were also examined to estimate the magnitude of maximum resistance (torque) and the corresponding angular rotation value. The average maximum resistance torque increased from 13.6 Nm at 4 degrees/s to 27.8 Nm at 100 degrees/s. The corresponding right angular rotation data (65-78 degrees), however, did not show any significant variation with loading rate. Posttest dissection of the specimens indicated that the type of injury observed was related to the rate of axial loading imposed on a specimen during testing.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Axial rotation component of thoracic scoliosis   总被引:3,自引:0,他引:3  
The axial rotation (rotation about a vertical axis) of the vertebrae, of the ribs, and of the back surface are components of the deformity recognized clinically as the "rib hump" in thoracic scoliosis. Relationships of these rotations to the lateral deviation and lateral curvature of the spine were studied in 40 patients with idiopathic scoliosis. Stereoradiographs of the spine and rib cage were used to measure three components of axial rotation: rotation of the vertebrae, of the rib cage, and of the plane of maximum curvature of the spine. Stereotopographs of the back surface were digitized to measure the axial rotation of the back surface. In individual patients, there were high correlations of all components of axial rotation at each spinal level with the corresponding vertebral lateral deviation from the spinal axis. By regression analyses of the maximum values of each rotation in each curve, the rotation of the apex vertebra was found to be generally of lesser magnitude than the rotation of the plane of maximum curvature of the spine and in an opposite sense in kyphotic curves. The rib cage rotation was generally of lesser magnitude than the vertebra rotation, and the back surface rotation was less than both of these skeletal rotations. Vertebra rotation correlated most closely with lateral deviation of the spine. Simple segmental coupling of axial rotation and lateral bending could not be responsible for this axial rotation.  相似文献   
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The remodeling of the pulmonary arterial tissue in response to a step change of the oxygen concentration in the gas in which a rat lives was recorded as function of time and function of O2 concentration. Three steps of changing from 20.9% to 17.2%, 13.6%, and 10% O2 were imposed. Earlier work in our laboratory has shown that pulmonary arterial tissue remodeling is significant in the first 24 h after a step change of oxygen tension. Hence we made measurements in this period. Furthermore, data were obtained for tissue remodeling of circumferential and axial lengths of the pulmonary arteries. We recorded the activities of gene expressions in the lung tissues by microarray, determined the dose response curves of gene expression in the homogenized whole lungs with respect to four levels of O2 concentration, and obtained the time courses of gene expression in the lung parenchyma in 30 days after a step decrease of O2 concentration from 20.9% to 10%. We would like to suggest that the correlation of gene expression with physiological function parameters, i.e., time, O2 tension, blood pressure, opening angle, wall thicknesses, etc., is the way to narrow down the search for specific genes for specific physiological functions. © 2001 Biomedical Engineering Society. PAC01: 8719Uv  相似文献   
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Summary Computerized Axial Tomography (CAT) has proved extremely useful for the diagnosis of cerebral cysticercosis. The calcified small, multiple, and scattered cysts provide a typical image on CAT.The collection of non-calcified cysts in the subarachnoid spaces (racemose form) or in the ventricles may produce areas of low density similar to that of the cerebrospinal fluid. The dilatation of the ventricular system, extreme degrees of hydrocephalus, areas of cerebral atrophy, and other related changes induced by the cysts in the subarachnoid spaces are also clearly shown in the CAT. Four personal cases are reported.  相似文献   
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