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111.
目的:探讨声学密度定量技术在诊断急性期非典型川崎病中的临床意义。方法:研究对象分3组:典型川崎病组34例(A组),非典型川崎病组31例(B组),正常对照组30例。应用HP5500型超声诊断仪测定左、右冠状动脉壁背向散射积分(IBS),以心包壁的IBS作为参照,用冠脉壁IBS和心包IBS比值作为校正值(IBS%)。结果:A组和B组的冠脉壁IBS值、IBS%值差异无显著性(P>0.05);A组和B组的冠脉壁IBS值、IBS%值均显著大于正常对照组(P<0.01),对冠脉壁IBS进行ROC分析,得到冠脉壁IBS最佳截点为41.5,据其诊断急性期川崎病的敏感性为93%,特异性为95%,准确性为94%。结论:声学密度定量技术有助于急性期川崎病的诊断,尤其对临床表现和冠脉病变不典型川崎病的诊断有重要价值。 相似文献
112.
113.
肿瘤细胞DNA干系倍体分析及其临床应用 总被引:2,自引:0,他引:2
DNA非整倍体是恶性肿瘤的特征性标志之一。测量和分析细胞核DNA含量与倍体对恶性肿瘤的病理诊断、恶性程度判定、疗效估价、预测预后具有重要价值。其主要测定方法有流式细胞术和细胞图像光度术。本文主要综述了肿瘤细胞DNA干系倍体分析及其临床应用的现状以及流式细胞术和细胞图像光度术两种检测方法的优缺点和相应的改进方法,希望对其应用于临床以提高诊断的准确性和预测肿瘤的发展起到积极的作用。 相似文献
114.
目的研究滑轨CT不同配准方式对肺癌大分割调强放疗摆位误差的影响。方法选取2016年10月至2017年10月在安徽医科大学第一附属医院放疗科就诊的肺癌患者24例,每周行滑轨CT扫描所得图像与原计划图像行灰度、骨性、手动3种模式在线配准,得出X、Y、Z轴3个方向平移误差,并进行统计分析。结果灰度配准、骨性配准和手动配准方式测量的X、Y、Z轴摆位误差分别为(0. 21±0. 16)、(0. 29±0. 15)、(0. 37±0. 22) cm,(0. 27±0. 16)、(0. 35±0. 25)、(0. 29±0. 19) cm,(0. 18±0. 12)、(0. 28±0. 16)、(0. 23±0. 14) cm,结果显示Y轴平移误差最大,其次为X轴,Z轴最小,且3组数据的差异有统计学意义(P <0. 05)。其中灰度模式在X、Y、Z轴上平移误差较骨性模式均缩小,灰度模式在X、Z轴上平移误差较手动模式有所缩小,差异有统计学意义(P <0. 05)。结论肺癌患者行图像引导大分割调强放疗时,应用滑轨CT中的灰度模式可缩小摆位误差。 相似文献
115.
《Neurocirugía (Asturias, Spain)》2014,25(6):261-267
ObjectiveThe purpose of this study was to asses the value of intraoperative cone-beam CT (O-arm) and stereotactic navigation for the insertion of anterior odontoid screws.Materials and methodsthis was a retrospective review of patients receiving surgical treatment for traumatic odontoid fractures during a period of 18 months.Procedures were guided with O-arm assistance in all cases. The screw position was verified with an intraoperative CT scan. Intraoperative and clinical parameters were evaluated. Odontoid fracture fusion was assessed on postoperative CT scans obtained at 3 and 6 months’ follow-upResultsFive patients were included in this series; 4 patients (80%) were male. Mean age was 63.6 years (range 35-83 years). All fractures were acute type ii odontoid fractures. The mean operative time was 116 minutes (range 60-160 minutes). Successful screw placement, judged by intraoperative computed tomography, was attained in all 5 patients (100%). The average preoperative and postoperative times were 8.6 (range 2-22 days) and 4.2 days (range 3-7 days) respectively. No neurological deterioration occurred after surgery. The rate of bone fusion was 80% (4/5).ConclusionAlthough this initial study evaluated a small number of patients, anterior odontoid screw fixation utilizing the O-arm appears to be safe and accurate. This system allows immediate CT imaging in the operating room to verify screw position. 相似文献
116.
Jill Drysdale Alison Porter-Armstrong 《Scandinavian journal of occupational therapy》2013,20(4):247-255
Background: Children with intellectual disabilities often have difficulties in daily tasks, requiring training to increase functional independence. This study measured the effectiveness of community skills training in a telephone task and a shopping task, and examined if community-based training was more effective than classroom-based training. Material and methods: A randomized control trial with 40 children aged 9–11years was completed. Intervention groups attended an eight-week training programme; the control group received no treatment. One intervention group practised skills in local shops. All participants were assessed before and after treatment in a shopping task and telephone task, using task analysis methodology. Results: Data showed a highly statistically significant difference between intervention and control groups in the shopping task (p=0.007); however, there was no significant difference between classroom and classroom supplemented by community-based learning in the shopping task. There was no significant difference between the intervention and control groups in the telephone task. Conclusion: Results suggested that skills training was effective in one of the skill areas with this client group. Further research is required to determine if community-based training is more effective than classroom-based learning. 相似文献
117.
目的探讨单源双能量CT扫描单能谱成像技术基物质图像在痛风结节诊断中的应用价值。方法选取本院2017年1月至2019年1月收治的77例高度怀疑痛风患者,均进行单源双能量扫描及尿酸基图和钙基图的分拆、重建,同时结合常规能量扫描进行诊断。以美国风湿病协会制定的痛风诊断标准为基准,计算单源双能量CT诊断痛风结节的敏感度、特异度与准确率。结果根据美国风湿病协会制定的痛风诊断标准,77例患者中57例患者确诊为痛风结节。共56例患者经单源双能量CT扫描检测到痛风结节,其中11例为单关节受累,45例为多关节受累。单源双能量CT诊断痛风的敏感度为91.23%,特异度为80.00%,准确率为87.18%;常规CT诊断痛风的敏感度为77.19%,特异度为60.00%,准确率为72.73%。单源双能量CT诊断痛风的敏感度、准确率显著高于常规CT(P<0.05)。单源双能量CT共检出痛风结节131处,直径0.1~14.7cm;常规CT共检出痛风结节104处,直径0.4~14.7cm,0.1~0.3cm痛风结节未能显示。结论单源双能量CT扫描操作简单、费用低,可利用单能谱成像技术基物质图像上的结晶标记颜色鉴别尿酸和非尿酸结晶沉积,痛风结节诊断的敏感度与准确率较高,且可检出较小痛风结节,值得在痛风的临床诊断中推广应用。 相似文献
118.
《Cochlear implants international》2013,14(1):34-43
AbstractDeaf children from signing programs provide new opportunities to investigate changes in sign and speech acquisition following cochlear implantation. We describe the acquisition of sign phonemes (location, movement, and handshapes) and speech phonemes (consonants) in 22 implanted children with diverse demographic backgrounds. New consonants and new sign phonemes emerged in developmentally expected sequences and with statistically significant correlation coefficients between cumulative number of new consonants and new sign phonemes over time. Regression slopes from plotted z scores revealed a burst in consonant and sign growth in early months post-implant, with continuous but plateauing growth over time. These results and documentation of developmental levels of sign and speech phoneme trajectories should be helpful to other researchers and to clinicians working with signing children who have cochlear implants. 相似文献
119.
《Radiography》2017,23(2):153-158
ObjectivesThe purpose of this investigation was to develop and examine the preliminary validity and reliability among radiographers of a test to assess trauma radiograph interpretation performance suitable for use among health professionals.MethodsStage 1 examined 14,159 consecutive appendicular and axial examinations from a hospital emergency department over a 12 month period to quantify a typical anatomical region case-mix of trauma radiographs. A sample of radiographic cases representative of affected anatomical regions was then developed into the Image Interpretation Test (IIT). Stage 2 involved prospective investigations of the IIT's reliability (inter-rater, intra-rater, internal consistency) and validity (concurrent) among 41 radiographers.ResultsThe IIT included 60 cases. The median (interquartile range) clinical experience of participants was 5 (2–10) years. Case scores were internally consistent (Cronbach's alpha = 0.90). Favourable inter-rater reliability (kappa > 0.70 for 58/60 cases, Intra-class correlation coefficient (ICC) > 0.99 for total score) and intra-rater reliability (kappa > 0.90 for 60/60 cases, ICC > 0.99 for total score) was observed. There was a positive association between radiographers' confidence in image interpretation and IIT score (coefficient = 1.52, r-squared = 0.60, p < 0.001).ConclusionsThe IIT developed during this investigation included a selection of radiographic cases consistent with anatomical regions represented in an adult trauma case-mix. This study has also provided foundational preliminary evidence to support the reliability and validity of the IIT among radiographers. The findings suggest that it is possible to assess image interpretation performance of adult trauma radiographs with this test. 相似文献
120.
《Radiography》2017,23(4):e99-e102
IntroductionThe aim of this research was to study the effect of exposure factors on image quality for digital screening mammography units in Kuwait which use Tungsten (W) targets with Rhodium (Rh) and Silver (Ag) as filters.MethodsMammography Accreditation Phantom Model 015 was imaged using a Hologic Selenia Digital mammography unit with W targets and Rh and Ag filters. Four images, each at 26, 28, 30, and 32 kVp, were obtained using each target-filter combination (W/Rh and W/Ag). The images were evaluated by five senior technologists for the number of specks, fibers and masses visible on each image. Statistical analysis was carried out using non-parametric tests at p = 0.05 level.ResultsThere were significant changes in the visibility of fibers and specks between different kVp values with W/Rh (p < 0.001). However, with W/Ag combination, significant differences were observed in the fibers only (p < 0.001). Among the kVp values used, 28 kV emerged as the optimal value. Comparison of images obtained with the two filter materials, led to significant differences in the visibility of fibers and specks (p < 0.008). At 32 kVp, there were significant differences in the visibility of specks only (p < 0.008).ConclusionA W/Rh target-filter combination provides better image quality than that provided by W/Ag. In particular, 30 and 32 kVp X-ray beams produce higher quality images than the lower kV values. 相似文献