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1.
平板运动试验阴性患者最大ST/HR斜率对冠心病的诊断价值   总被引:3,自引:1,他引:2  
目的探讨平板运动试验阴性患者最大ST/HR斜率对冠心病的诊断价值.方法选择122例平板运动试验阴性而临床有明显冠心病指征的患者进行冠状动脉造影,测定其最大ST/HR斜率.结果平板运动试验阴性患者最大ST/HR斜率诊断冠心病的敏感性为68.2%,特异性为80.8%,准确性为76.2%;运动峰值心率<预计最大心率之85%组最大ST/HR斜率诊断冠心病的敏感性为92.8%,特异性为86.7%,准确性为89.7%,高于运动峰值心率≥预计最大心率之85%组.结论平板运动试验阴性患者最大ST/HR斜率对冠心病的临床诊断有较高的敏感性、特异性和准确性,尤其是对低运动水平的患者,对减少运动试验诊断的漏诊率具有重要意义.  相似文献   
2.
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   
3.
气功对冠心病人CM_5ST段/心率斜率的影响   总被引:1,自引:0,他引:1  
37名冠心病患者随机分为气功治疗组(22人)和对照组(15人)。气功治疗组接受12周动功治疗,对照组接受安慰剂治疗,治疗前后均测定CM_5 ST段/心率斜率。结果发现动功治疗组CM_5 ST段/心率斜率减少,而对照组不变或增大,两组有显著性差异,ST段下移及常规分级运动试验其它指标在两组间无显著差异。表明CM_5ST段/心率斜率是一个敏感的心肌缺血指标。  相似文献   
4.
Standing posture is made possible by hip extension and lumbar lordosis. Lumbar lordosis is correlated with pelvic parameters, such as the declivity angle of the upper surface of the sacrum and the incidence angle, which determine the sagittal morphotype. Incidence angle, which is different for each individual, is known to be very important for upright posture, but its course during life has not yet been established. Incidence angle was measured on radiographs of 30 fetuses, 30 children and 30 adults, and results were analysed using the correlation coefficientr and Student's t test. A statistically significant correlation between age and incidence angle was observed. Incidence angle considerably increases during the first months, continues to increase during early years, and stabilizes around the age of 10 years. Incidence is a mark of bipedism, and its role in sagittal balance is essential.  相似文献   
5.
Summary We report a case of non-Hodgkin's lymphoma with CNS involvement confined to the epidural space causing cranial suture diastasis. Cerebrospinal fluid and bone marrow were normal. Two cases only of cranial epidural lymphoma have been reported in the literature; in both cases, the leptomeninges were also involved but without suture diastasis.  相似文献   
6.
Surgical rejuvenation of the upper face involves the correction of excess and lax forehead, eyelid, and periorbital skin. Improving the appearance by correcting the effects of aging involves a combination of blepharoplasty and open coronal foreheadplasty. Many surgeons and several reports question the safety of both procedures being performed concomitantly. The difficulty arises in precisely balancing the skin excision from the frontal forehead and upper eyelid areas. Over-resection of skin may result in incomplete closure of the eyelid and dry-eye syndrome, while an inadequate resection may produce a poor aesthetic result. There is no large series that documents the safety and effectiveness of these two procedures being performed concomitantly. Furthermore, with the recent and rapid development of complex multiplanar endoscopic facial rejuvenation techniques, the basic open forehead-plasty has become increasingly overlooked as a legitimate, efficacious technique for rejuvenation of the upper face. The technique utilized in this series is presented in detail. The consistently excellent results obtained satisfy the aesthetic goals of patients as well as the goals of surgeons, and suggest a renewed interest in the technique based upon its simplicity and easily reproducible results.  相似文献   
7.
肝静脉的冠状断层解剖学研究   总被引:4,自引:1,他引:4  
目的为MRI和多层螺旋CT在冠状断面上诊断肝疾患及肝外科手术提供断层解剖学依据。方法用30例成人躯干部连续冠状断层标本、10例成人腹部MRI冠状图像及5例成人肝内管道多层螺旋CT三维重建图像,观测了肝左、中、右静脉及其重要属支的走行、分布及其与肝门静脉的关系。结果依左外叶的外形特征,将肝左静脉的回流形式分为4型。来自段Ⅷ腹侧部的静脉全部汇入肝中静脉,来自段Ⅷ背侧部的静脉全部汇入肝右静脉。而位于段Ⅷ腹侧部和背侧部之间的静脉(V8i),其回流形式可分为3型。肝右静脉的主干多出现于下腔静脉及其稍后层面,在冠状断面上可分为4型。结论冠状断面在显示肝静脉及其属支的上、下走行方面具有明显优势。以V8i为标志,将段Ⅷ分为腹侧和背侧两个亚段。这种亚段划分有利于探讨一种新的和更加安全的肝外科手术方式。  相似文献   
8.
9.
BackgroundIt has been hypothesized that increasing posterior tibial slope can influence condylar rollback and play a role in increasing knee flexion. However, the effects of tibial slope on knee kinematics are not well studied. The objective of this study is to assess the effects of tibial slope on femorotibial kinematics and kinetics for a posterior cruciate retaining total knee arthroplasty design.MethodsA validated forward solution model of the knee was implemented to predict the femorotibial biomechanics of a posterior cruciate retaining total knee arthroplasty with varied posterior slopes of 0°-8° at 2° intervals. All analyses were conducted on a weight-bearing deep knee bend activity.ResultsIncreasing the tibial slope shifted the femoral component posteriorly at full extension but decreased the overall femoral rollback throughout flexion. With no tibial slope, the lateral condyle contacted the polyethylene 6 mm posterior of the midline, but as the slope increased to 8°, the femur shifted an extra 5 mm, to 11 mm posterior of the tibial midline. Similar shifts were observed for the medial condyle, ranging from 7 mm posterior to 13 mm posterior, respectively. Increasing posterior slope decreased the posterior cruciate ligament tension and femorotibial contact force.ConclusionThe results of this study revealed that, although increasing the tibial slope shifted the femur posteriorly at full extension and maximum flexion, it reduced the amount of femoral rollback. Despite the lack of rollback, a more posterior location of condyles suggests lower chances of bearing impingement of the posterior femur and may explain why increasing slope may lead to higher knee flexion.  相似文献   
10.
基坑边坡变形和稳定性的离心试验研究   总被引:1,自引:0,他引:1  
通过土工离心模型试验对上海某放坡式开挖基坑边坡的变形特性和稳定性进行了研究,揭示了基坑边坡变形的时间效应及其对边坡稳定性的影响。试验结果表明能长期稳定的边坡其边坡变形速率呈现出加速、接近匀速和衰减等3个明显的阶段;能瞬时稳定但不能长期稳定的边坡,其失稳发生在边坡位移速率增大的阶段。  相似文献   
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