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1.
针对日常使用中遇到的Brilliance 16排螺旋CT高压系统、机架以及控制器局域网络(CAN)通讯等故障现象进行分析与维修,最终通过更换滤波电容、机架数据采集控制器(DMC)电源以及信号刷等配件得以排除故障。通过对故障准确判断以及合理运用厂家Service模式下的维修工具软件快速解决故障,保障了影像科检查工作的顺利进行,从而提高设备的稳定性。  相似文献   
2.
董朝晖  卢惠娟 《全科护理》2022,20(3):325-329
介绍家庭适应的相关概念及起源,阐述家庭适应方面常用测量工具的发展历程、内容结构、适用人群、评分方法、信度与效度、应用现状等情况,以期能够指导临床工作者在实践过程中选择合适的家庭适应测量工具,旨在帮助研究者进一步开发适用于我国癌症生存者的特异性家庭适应测量工具。  相似文献   
3.
目的 探讨自行设计的淋巴水肿上肢体积测量装置在测量淋巴水肿患者肢体肿胀程度方面的应用效果。 方法 选择2018年7月至2018年12月在我院淋巴水肿专病门诊就诊的患者70例,按照随机数字表法分为观察组(n=35)和对照组(n=35),观察组采用淋巴水肿上肢体积测量装置评估患者治疗前后患侧肢体的肿胀程度,对照组采用传统的软尺测量+不可擦记号笔做标记的方法测量患者治疗前后患侧肢体的周径变化情况。 结果 满意度评价中观察组的满意率明显高于对照组(P<0.05),护士操作难易度比较中,观察组护士认为操作简单的频率明显高于对照组(P<0.05)。 结论 自行设计的淋巴水肿上肢体积测量装置可以提高患者的满意度,方便护士操作,值得临床推广。  相似文献   
4.
Objective: Quadriceps dysfunction has been suggested as a complication after medial patellofemoral ligament (MPFL) reconstruction. The purpose of this study was to investigate changes in knee extensor strength before and after MPFL reconstruction.

Methods: Twenty patients who underwent MPFL reconstruction for unilateral recurrent patellar dislocation (18 females and 2 males; mean age 20.8 ± 7.6 years) were examined. The peak isometric torque at 60° and 90° of knee flexion and isokinetic knee extensor strength at speeds of 60°/s and 90°/s in operated and non-operated legs were measured using a dynamometer preoperatively and 6 months, 1 year, and 2 years postoperatively. The following parameters were evaluated: (1) body weight-adjusted muscle strength, (2) improvement index (post-/preoperative value × 100) (%), and (3) extensor strength ratio (operated/non-operated value × 100) (%).

Results: The mean knee extensor strength in both operated and non-operated legs significantly increased 2 years after surgery compared with that before surgery. At 2 years postoperatively, the improvement indexes of the isometric knee extensor strength at 60° and 90° and of the isokinetic knee extensor strength at 60°/s and 90°/s were 237%, 192%, 318%, and 186%, respectively, in the operated legs and 144%, 124%, 140%, and 140%, respectively, in the non-operated legs. At 2 years postoperatively, the mean isometric knee extensor strength ratios at 60° and 90° and the isokinetic knee extensor strength ratios at 60°/s and 180°/s were 81%, 84%, 81%, and 82%, respectively.

Conclusions: Knee extensor strength was improved in most patients after MPFL reconstruction, at least compared with that before surgery, although an approximately 20% deficit against the non-operated legs remained even 2 years after surgery.  相似文献   

5.
Syringe infusion pumps are used for the administration of short-acting drugs in anaesthesia and critical care medicine, but are prone to flow irregularities at low flow rates. A flow-controlled syringe infusion pump using an integrated flow sensor for feedback control represents a new approach to overcoming these limitations. This study compares the performance of a prototype flow-controlled syringe pump both at start-up, and during vertical displacement manoeuvres, with that of a standard infusion syringe pump. The novel pump almost completely eliminated delays at start-up and flow irregularities during hydrostatic pressure changes. Related fluctuations in plasma drug concentration were minimised and the known disadvantages of standard syringe infusion pumps currently used in clinical practice were reduced. Besides providing fast start-up to steady-state flow and precise continuous drug delivery at low flow rates during hydrostatic pressure changes, the new pump offers the potential for the development of target-controlled infusion algorithms for short-acting cardiovascular and other drugs.  相似文献   
6.
7.
Control risk regression is a diffuse approach for meta-analysis about the effectiveness of a treatment, relating the measure of risk with which the outcome occurs in the treated group to that in the control group. The severity of illness is a source of between-study heterogeneity that can be difficult to measure. It can be approximated by the rate of events in the control group. Since the estimate is a surrogate for the underlying risk, it is prone to measurement error. Correction methods are necessary to provide reliable inference. This article illustrates the extent of measurement error effects under different scenarios, including departures from the classical normality assumption for the control risk distribution. The performance of different measurement error corrections is examined. Attention will be paid to likelihood-based structural methods assuming a distribution for the control risk measure and to functional methods avoiding the assumption, namely, a simulation-based method and two score function methods. Advantages and limits of the approaches are evaluated through simulation. In case of large heterogeneity, structural approaches are preferable to score methods, while score methods perform better for small heterogeneity and small sample size. The simulation-based approach has a satisfactory behavior whichever the examined scenario, with no convergence issues. The methods are applied to a meta-analysis about the association between diabetes and risk of Parkinson disease. The study intends to make researchers aware of the measurement error problem occurring in control risk regression and lead them to the use of appropriate correction techniques to prevent fallacious conclusions.  相似文献   
8.
BackgroundChildren with cerebral palsy (CP) have poor postural control. Horseback riding (HR) is an alternative treatment shown to improve postural control among children with CP. However, there is a paucity of research investigating the underlying mechanisms responsible for improving postural control during HR.Research questionWhat are the three-dimensional biomechanical responses of the trunk and pelvis during HR among children with CP and with typical development (TD)?MethodsThe participants, aged 4–12 years old, were inexperienced horseback riders, consisting of 10 children with TD and 10 children with spastic diplegia CP (SDCP) with GMFCS level III. Participants donned inertial measurement units (IMU) on their trunk and pelvis in order to measure angular displacement and velocity. An additional IMU was placed on the horse’s lumbosacral joint. The mean absolute relative phase (MARP) and deviation phase (DP) were calculated from each plane of movement for the angular displacement and velocity across the gait cycle of the horse. Differences between groups were analyzed using independent t-tests.ResultsThe MARP in the frontal plane was lower in the SDCP group, when compared to the TD group (p = 0.01). Additionally, no differences were found between groups for the DP along all three axes. However, the TD group demonstrated greater pelvic movement variability in relation to the horse’s pelvis movement, when compared to the SDCP group.SignificanceChildren with SDCP demonstrated an in-phase coupling pattern with decreased variability of pelvic movement in relation to the horse’s pelvis.  相似文献   
9.
张颖  王晓玲  杨婷  尹专叶  胡雁 《护理学报》2021,28(14):22-25
目的 根据上臂围选用合适尺寸袖带测量血压的最佳证据进行总结,为临床提供理论参考。方法 根据循证护理的方法确立问题,利用计算机按“6S”证据模型,检索有关血压测量袖带尺寸的选择,包括指南、专家共识、临床决策和证据总结,由4名完成循证护理培训的研究员对纳入的文献独立评价,并对选取出符合质量标准的文献进行证据提取。结果 该研究纳入证据7篇,其中临床实践指南4篇、专家共识2篇、系统评价1篇,对相关证据进行汇总,总结了3方面内容。结论 应加强对医护人员血压测量规范流程的培训,根据患者的上臂围选用尺寸适合的袖带进行血压测量,减少因袖带不当带来的测量误差以减少高血压误诊和漏诊。  相似文献   
10.
目的:通过交叉对比神经网络(CCNN)实现心音信号的自动分类,从而对心血管疾病进行早期诊断。方法:实验基于PhysioNet/Cinc 2016心音数据库。训练集和测试集数据来自互斥的健康受试者/病理患者,并以4:1的比例进行划分,输入CCNN。CCNN利用深度卷积神经网络进行特征提取,结合基于信息的相似度度量理论(IBS),对特征向量间的相似性进行度量并分类。结果:实验结果得出灵敏度为0.834 6,特异性为0.962 3,最终大赛综合得分为0.898 5。结论:CCNN使用交叉对比的输入模式扩充数据量,引入信号间的对比信息,同时在神经网络的训练过程中应用统计学思想,使网络具备良好的泛化性,更加适应医学数据量较少的场景,在心音分类中取得较好的结果。  相似文献   
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