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31.
《Radiography》2019,25(4):320-326
IntroductionRadiation therapy students need to demonstrate appropriate communication skills when entering the clinical environment. To assist students with preparation for their first clinical placement a clinical reasoning module comprising theory and practical sessions was developed. This paper describes the module and presents the results of student evaluations.MethodsThe module consisted of lectures, observational role-play and participatory role-play. Students were ultimately tasked with providing information to a simulated patient (SP). Each student received feedback independently from the SP, peers and facilitator. At the conclusion of the module, students had the opportunity to provide feedback via an anonymous survey (8 Likert scale questions with space for written comment). Data was analysed both quantitatively and qualitatively.ResultsFour hundred and thirty seven students were enrolled in the course between 2008 and 2016 and the response rate of the survey was 93%. Even though most students reported some level of anxiety before and during the role-play sessions, the majority of students perceived all aspects of the module to be extremely/very useful. The most useful aspect of the module (Likert scale assessment) was the feedback provided by the SP. The two most important themes arising from the thematic analysis were gaining an understanding of the role of the radiation therapist and the complexities of patient interactions.ConclusionOverall, the module was deemed successful with students becoming conscious of newly acquired clinical knowledge whilst acknowledging patient feelings during interactions. Collaborative critiquing contributed to students' ability to self-reflect to improve clinical interactions. 相似文献
32.
目的观察模拟失重效应对下肢肌萎缩的影响及中药红景天的干预作用。方法 16名成年男性健康志愿者随机分为对照组(8人)和用药组(8人),进行45 d-6°头低位卧床模拟长期失重效应实验。卧床期间,用药组和对照组每天分别服用红景天(红益胶囊)和安慰剂。卧床前、中、后动态测量小腿围径;并采用MRI技术,测试和分析卧床前、后大腿和小腿肌群最大横截面积和肌肉体积的变化。结果1)卧床期间用药组和对照组小腿围径进行性下降,在卧床30和45 d均显著下降(P0.01),但用药组下降幅度显著减少(P0.05);2)卧床45 d,用药组和对照组大腿和小腿肌肉最大横截面积均显著降低(P0.01),其中小腿比目鱼肌下降幅度最大。用药组肌肉最大横截面积的减少较对照组均有改善作用(P0.05);3)对照组大腿和小腿肌群肌肉体积在卧床45 d均显著下降(P0.01),以比目鱼肌体积下降最为明显,用药组下降幅度显著减少,且比目鱼肌对抗作用最为明显(P0.01)。结论 45 d-6°头低位卧床引起进行性加重的肌萎缩,中药红景天可部分对抗模拟长期失重效应诱导的下肢肌萎缩。 相似文献
33.
Predicting Failure Load of the Femur with Simulated Osteolytic Defects using Noninvasive Imaging Technique in a Simplified Load Case 总被引:1,自引:0,他引:1
Lee T 《Annals of biomedical engineering》2007,35(4):642-650
Currently, there is no proven sensitive or specific method for predicting pathological fracture of the femur. The clinical
management of lytic femoral metastases is based on geometric measurement of the bone, of the defect, or both. However, the
mechanical behavior of a structure depends on both its material and geometric properties. Our hypothesis is that a change
in bone structural properties as the result of tumor induced osteolysis determines the fracture risk in bones with skeletal
metastases. We developed a method of QCT (Quantitative Computed Tomography) combined with engineering beam analysis as a noninvasive
tool for measuring the material and geometric properties of the femur with simulated lytic defects in the intertrochanteric
region. In this ex-vivo study we prove that engineering beam structural analysis applied to serial transaxial QCT scans through
human femora with simulated lytic defects at the proximal femur predicts the load at failure and location of fracture better
than current clinical guidelines. Structural rigidity measured by QCT in this study may be used to predict the load carrying
capacity of femurs with metastatic defects and, furthermore, may be used when the tumor has weakened the bone sufficiently
such that pathological fracture is imminent and prophylactic stabilization is necessary.
相似文献
Taeyong LeeEmail: |
34.
尾悬吊模拟失重大鼠肺组织一氧化氮合酶的变化 总被引:2,自引:1,他引:2
目的 :研究尾悬吊模拟失重大鼠肺组织一氧化氮合酶 (NOS)的变化。方法 :采用尾悬吊模拟失重 ,分为悬吊 7日和 2 1日及相应对照 4个组 ,每组 10只健康雄性 SD大鼠 ,共 4 0只大鼠。并采用免疫组织化学技术检测肺组织 NOS的表达情况。结果 :同正常对照组相比 ,7日尾悬吊模拟失重大鼠肺组织诱导型一氧化氮合酶(i NOS)的表达水平明显增高 (P<0 .0 5 ) ;2 1日的表达水平仍显著增高 (P<0 .0 5 ) ,同时可见血管内皮细胞随着时间延长阳性数目显著增多 (P<0 .0 1)。结论 :在模拟失重条件下肺组织 i NOS的表达水平增高 相似文献
35.
目的考察聚(L-乳酸)(PLLA)植入剂体内外降解特性黏数和失重变化的相关性。方法以辛酸亚锡为催化剂,通过直接缩聚法制备聚(L-乳酸)(PLLA)树脂,经精制得药用辅料;将药用辅料通过特定设备压制成空白植入剂,考察其在大白兔体内的降解情况,并与其在pH7.4的磷酸盐缓冲液的体外降解相比较。结果聚(L-乳酸)植入剂样品降解后的特性黏数与降解时间(wk)呈指数关系,失重百分率与降解时间(wk)呈线性关系。结论体内的特性黏数与体外的特性黏数数值相近,体外失重比体内快。 相似文献
36.
模拟失重对大鼠肺动脉eNOS表达的影响 总被引:1,自引:1,他引:0
目的通过研究模拟失重对大鼠肺动脉血管内皮型一氧化氮合酶(eNOS)表达的影响,探讨肺动脉反应性改变的发生机制。方法采用尾悬吊大鼠模拟失重,分为模拟失重组(尾悬吊14天)和对照组,每组8只健康雄性Wistar大鼠,用蛋白免疫印迹分析模拟失重组和对照组大鼠肺动脉组织eNOS表达,硝酸还原酶法测定肺动脉组织一氧化氮(NO)含量。结果同对照组相比,模拟失重组大鼠肺动脉组织eNOS表达增强,胶片图像扫描后的相对光密度值为247±2·60,对照组的相对光密度值为141±1·72,两组间有显著性差异(P<0·01)。模拟失重组肺动脉组织NO含量亦增加,其浓度为15·7±4·1μmol/L,对照组为7·6±3·2μmol/L,两组间有显著性差异(P<0·05)。结论模拟失重条件下肺动脉eNOS表达增加可能促进了立位耐力不良的发生。 相似文献
37.
目的:评价双能量减影胸部成像在检出模拟肺部病变中的价值.方法:在仿真胸部体模中放置模拟网状、线状和结节病变结构,对其实施数字X线摄影(DR)的双能量减影成像.采集DR胸片、能量减影的软组织和骨骼胸部图像,4位放射医师分别对这3幅图像进行阅片评分,所有数据采用配对资料t检验进行统计学分析.结果:模拟网状、线状及大结节(直径≥1cm)结构在DR胸片和双能量减影胸片体模图像中,可见度两者无显著性差异(P>0.05).小结节(直径<1cm)模拟结构的两种成像方法比较,可见度有显著性差异(P<0.05).结论:双能量减影胸部成像具有较高的敏感性,对肺部低对比小结构病变的检出率更高. 相似文献
38.
P. Gallagher S. Trappe M. Harber A. Creer S. Mazzetti T. Trappe B. Alkner P. Tesch 《Acta physiologica (Oxford, England)》2005,185(1):61-69
Aim: This investigation determined the effects of 84 days of bedrest on the composition of myosin heavy chain (MHC) in single skeletal muscle fibres with and without a resistance‐training countermeasure programme. Methods: Muscle biopsies were obtained from the m. vastus lateralis (VL) and m. soleus (SOL) before and after 84 days of bedrest. While control (BR) subjects (VL n = 9; SOL n = 3) refrained from exercise, BRE subjects (VL n = 8; SOL n = 3) performed knee extensor and plantar flexor resistance exercise every third day. Approximately 110 fibres per sample were analysed for MHC composition using SDS‐PAGE. Results: BR–VL had 16 and 14% decreases (P < 0.05) in MHC I and IIa fibres, respectively. There were 10% increases (P < 0.05) in MHC I/IIa, IIa/IIx, I/IIa/IIx, and a ~30% increase (P < 0.05) in total hybrid fibres. BRE‐VL showed a 15% reduction (P < 0.05) in MHC I fibres, no change in MHC IIa fibres, and a 13% increase (P < 0.05) in total hybrids. BR–SOL had a 19% decrease (P < 0.05) in MHC I fibres with a 22% increase in total hybrids. BRE–SOL showed no change in MHC composition across all fibre types. Conclusion: These data suggest that the exercise countermeasures programme prevented MHC shifts in the SOL and mitigated MHC shifts in the VL. Furthermore, in the VL it appears that the resistance training programme employed in this investigation during bedrest, emphasized the use of MHC IIa phenotype muscle fibres. 相似文献
39.
Trappe TA Burd NA Louis ES Lee GA Trappe SW 《Acta physiologica (Oxford, England)》2007,191(2):147-159
AIM: The goal of this investigation was to test specific exercise and nutrition countermeasures to lower limb skeletal muscle volume and strength losses during 60 days of simulated weightlessness (6 degrees head-down-tilt bed rest). METHODS: Twenty-four women underwent bed rest only (BR, n = 8), bed rest and a concurrent exercise training countermeasure (thigh and calf resistance training and aerobic treadmill training; BRE, n = 8), or bed rest and a nutrition countermeasure (a leucine-enriched high protein diet; BRN, n = 8). RESULTS: Thigh (quadriceps femoris) muscle volume was decreased (P < 0.05) in BR (-21 +/- 1%) and BRN (-24 +/- 2%), with BRN losing more (P < 0.05) than BR. BRE maintained (P > 0.05) thigh muscle volume. Calf (triceps surae) muscle volume was decreased (P < 0.05) to a similar extent (P > 0.05) in BR (-29 +/- 1%) and BRN (-28 +/- 1%), and this decrease was attenuated (P < 0.05) in BRE (-8 +/- 2%). BR and BRN experienced large (P < 0.05) and similar (P > 0.05) decreases in isometric and dynamic (concentric force, eccentric force, power and work) muscle strength for supine squat (-19 to -33%) and calf press (-26 to -46%). BRE maintained (P > 0.05) or increased (P < 0.05) all measures of muscle strength. CONCLUSION: The nutrition countermeasure was not effective in offsetting lower limb muscle volume or strength loss, and actually promoted thigh muscle volume loss. The concurrent aerobic and resistance exercise protocol was effective at preventing thigh muscle volume loss, and thigh and calf muscle strength loss. While the exercise protocol offset approximately 75% of the calf muscle volume loss, modification of this regimen is needed. 相似文献
40.
目的 比较TF、K3和EndoWave 3种机用镍钛锉预备S形树脂模拟根管的成形能力.方法 120个S形树脂模拟根管,随机分为3组,每组40例,使用TF、K3和EndoWave 3种器械分别进行根管预备,记录预备时间;数码显微镜获取预备前、后根管图像,使用Photoshop和ImageJ软件进行图像重叠,测量预备后根管冠方弯曲角度和根方弯曲角度的变化值;从根尖止点开始,每隔1 mm测量根管内、外侧壁树脂去除量,共10个测量点.以外弯量减去内弯量,表示中心定位能力.单因素方差分析进行统计学检验,显著性水平0.05.结果 TF预备时间为(14.00 ±4.56)s,显著短于K3和EndoWave[(59.53±35.92)s和(44.00±14.38)s] (P <0.05).3种器械预备后根管冠方和根方弯曲角度变化差异无统计学意义(P>0.05).3种器械预备后,根尖弯曲处,TF在内侧壁树脂去除量显著小于EndoWave和K3(P<0.05);冠部弯曲处,TF在外侧壁去除量显著小于K3(P<0.05);根管直线段,TF在内侧壁的去除量显著小于EndoWave和K3(P<0.05).中心定位能力方面,TF在距根尖孔L 5~ 9mm位点均显著优于EndoWave(P<0.05);除距根尖止点6mm位点以外,其他位点TF均与K3差异无统计学意义.结论 TF预备S形树脂模拟根管效率高,不良预备形较少且根管偏移较小. 相似文献