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Identifying transmission of hot spots with temporal trends is important for reducing infectious disease propagation. Cluster analysis is a particularly useful tool to explore underlying stochastic processes between observations by grouping items into categories by their similarity. In a study of epidemic propagation, clustering geographic regions that have similar time series could help researchers track diffusion routes from a common source of an infectious disease. In this article, we propose a two-stage scan statistic to classify regions into various geographic clusters by their temporal heterogeneity. The proposed scan statistic is more flexible than traditional methods in that contiguous and nonproximate regions with similar temporal patterns can be identified simultaneously. A simulation study and data analysis for a dengue fever infection are also presented for illustration.  相似文献   
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《Radiography》2022,28(3):780-787
IntroductionMagnetic Resonance Imaging remains an anxious experience for many, often exhibiting as fear of enclosed spaces. A useful metric to assess its prevalence and impact in practice is premature termination due to claustrophobia. Incidence varies and depends on many factors such as the physical nature of the imaging equipment and examination being undertaken, as well as the patient themselves.MethodsScan appointment data from between April 2019–March 2021 was extracted and reviewed. Analysis included the type of scanner used, patient age, sex, examination area, funding source, attendance and completion status. Binomial logistic regression was performed to look for any relevant predictors of failure to scan due to claustrophobia.ResultsOverall incidence of incomplete examinations due to claustrophobia was 0.76%. Whilst the majority of scans were performed on conventional systems, those undergoing Open scans were over three times more likely to fail a scan due to claustrophobia, whilst those undergoing UpRight scanning were half as likely. Likelihood of claustrophobia increases with females, those between 45-64years of age, funded by the NHS and entering the scanner head first or having a head scan.ConclusionIncidence of incomplete scanning is below 1% but with the potential for further reduction with implementation and use of improved scanner design and technology. Understanding the impact of other variables is also useful to raise awareness of those at greater risk of claustrophobia. However, there are wider influences beyond data alone to consider and account for.Implications for practiceWhilst occurrence of claustrophobia is low, there remains a cost impact, as well as an importance in understanding the patient experience. Drawing on operational data can help provide a limited, generalised view to support service improvement.  相似文献   
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目的 探讨多层螺旋CT增强扫描鉴别诊断肝血管瘤(HH)与肝转移癌的价值,为临床准确诊治提供依据。方法 2018年1月~2020年1月我院收治的肝占位性病变患者133例,接受多层螺旋CT增强扫描检查。综合组织病理学和影像学检查诊断,其中HH 102例,肝转移癌31例。结果 HH组肝血流通过时间为(14.3±1.7)s,肝血容量为(25.4±2.6)ml/100 g,毛细血管表面通透性为(33.1±4.6),显著高于肝转移癌组【分别为(9.4±1.0)s、(13.7±1.6)ml/100 g和(27.1±3.1),P<0.05】,而肝动脉灌注为(0.3±0.1)%,肝血流为(151.3±15.9)ml/100g/min,显著低于肝转移癌组【分别为(0.5±0.2)%和(189.3±19.6)ml/100g/min,P<0.05】;HH病灶融合发生率为60.8%,肝包膜下分布为74.5%,靶环征为33.3%,显著高于肝转移癌组(分别为3.2%、0.0%和0.0%,P<0.05),而病灶呈类圆形中心低密度发生率为2.0%,牛眼征为1.0%,显著低于肝转移癌组的61.3%和48.4%(P<0.05);以组织病理学检查结果为金标准,CT增强扫描诊断HH的灵敏度为89.2%,特异度为77.4%,准确度为86.5%,与病理学检查诊断的一致性较好(Kappa值为0.638)。结论 使用多层螺旋CT增强扫描检查诊断HH价值高,可为临床合理地制定处置方案起指导作用。  相似文献   
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目的 探讨256层CT动态增强扫描联合血清甲胎蛋白异质体(alpha-fetoprotein-L3,AFP-L3)比率、高尔基体蛋白73(Golgi protein 73,GP73)对乙肝相关性肝癌的诊断价值。 方法 将2021年1月至2021年6月入住空军军医大学唐都医院的乙型病毒性肝炎相关性肝细胞癌(hepatocellular carcinoma,HCC)患者58例(HCC组)和良性肝病患者63例(良性肝病组)纳入研究,检测患者血清AFP、AFP-L3%和GP73水平,利用256层CT动态增强扫描技术,对患者行上腹部CT扫描。分析比较两组患者的CT影像表现,分别探讨单独应用CT扫描、肿瘤标志物检测及联合运用两种技术诊断乙型病毒性肝炎相关性HCC的价值。 结果 HCC组的AFP-L3%、GP73浓度明显高于良性肝病组,差异均有统计学意义(t=9.38,5.99,均P<0.01);CT扫描、AFP-L3%、GP73浓度联合检测的ROC曲线下面积最大。CT扫描诊断HCC的灵敏度为87.93%,特异度为93.65%,准确率为90.91%;AFP-L3%诊断HCC的cut-off值为9.31%,诊断灵敏度为81.03%,特异度为87.30%,准确率为84.29%;GP73诊断HCC的cut-off值为105.62 ng/mL,诊断灵敏度为72.41%,特异度为82.54%,准确率为77.69%;CT扫描、AFP-L3%、GP73浓度联合检测的灵敏度为91.38%,特异度为93.65%,准确率为92.56%。 结论 联合运用CT动态增强扫描、血清AFP-L3%、GP73浓度检测对乙型病毒性肝炎相关性肝细胞癌诊断的灵敏度和准确率较运用单一技术均有所提高,联合运用这几种指标对乙型病毒性肝炎相关性HCC的准确诊断具有重要的临床价值。  相似文献   
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《中国现代医生》2020,58(24):166-168+172
目的 探究临床护理路径在行腹部CT增强扫描检查患者中的应用效果。方法 收集本院2017年7月~2018年6月收治的120例行腹部CT增强扫描检查患者的临床资料,依据不同的干预方法归纳为对照组和实验组,各60例。前者采取常规护理方法,后者采取临床护理路径。对照并分析两组患者的检查配合度、不良反应发生率、护理满意度及护理差错数。结果 实验组患者的检查配合度为93.3%,明显优于对照组的73.3%(P0.05);实验组患者的不良反应发生率为5.0%,明显低于对照组的18.3%(P0.05);实验组患者的满意度评分为(4.37±0.40)分,明显优于对照组患者的(3.26±0.73)分(P0.05);实验组护理差错共1次,明显少于对照组的8次(P0.05)。结论 临床护理路径在腹部CT增强扫描检查中应用效果较好,能够明显提升患者的依从性,进而更好地配合检查,提高患者的满意度,具有较高的临床实用性。  相似文献   
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《肿瘤防治研究》2020,(7):517-523
Objective To investigate the correlation of rib 99mTc-MDP foci on whole-body bone scan with clinical variables and rib metastases in nasopharyngeal carcinoma(NPC) patients, and to screen the risk factors of rib metastases. Methods We retrospectively reviewed 312 NPC patients with rib 99mTc-MDP foci on wholebody bone scan. Chi-square test and logistic regression were performed to evaluate the correlation between clinical variables and rib metastases. Results In all 312 NPC patients, rib metastases were associated with T stage, skull base bone invasion, other bone metastasis, number of rib foci, lateral localization on rib and foci type (P<0.01), and the risk factors of rib metastasis included skull base bone invasion, other bone metastases, lateral localization on rib and foci type (P<0.05). In 176 patients with pure rib foci, rib metastases were closely related to T stage, skull base bone invasion, other bone metastasis, number of rib foci and lateral localization on rib (P<0.05), while only lobar distribution (P=0.029) was the effective risk factor. In 198 patients with single rib focus, rib metastases were affected by skull base bone invasion and foci type (P<0.01), while only foci type (P=0.000) was the effective risk factor. In all 566 rib foci, uptake level and localization on rib were the effective risk factors of rib metastases(P<0.01). Conclusion In NPC patients with rib foci on whole body bone scan, the effective risk factors of rib metastases include skull base bone invasion, other bone metastases, lateral localization on rib, foci type, uptake level and anterior and posterior localization on rib. Follow up should be the main way for the pure rib foci on unilateral ribs. For multiples rib foci on bilateral ribs or single rib focus combined with other bones foci, additional image modalities should be required to exclude bone metastasis. © 2020, CHINA RESEARCH ON PREVENTION AND TREATMENT. All rights reserved.  相似文献   
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ObjectiveTo investigate the value of application of low-dose and optimized length CT scan on puncture results, complications and patients’ radiation dosage during CT-guided percutaneous biopsy of pulmonary nodules (PTNB).MethodsA total of 231 patients with PTNB under CT guidance were collected. Low dose scanning utilized tube current of 20 mA as compared with 40 mA in conventional dosage. Optimized length in CT is defined as intentionally narrowing the range of CT scanning just to cover 25 mm (5 layers) around the target layer during needle adjustment. According to whether low-dose scans and optimized length scans techniques were utilized, patients were divided into three groups: conventional group (conventional sequence + no optimization), optimized length group (conventional sequence + optimized length), and low-dose optimized length group (low dose sequence + optimized length). The ED (effective dose), the DLP (dose length product), the average CTDIvol (Volume CT dose index), total milliampere second between subgroups were compared.ResultsCompared with the conventional group, ED, intraoperative guidance DLP, total milliseconds and operation time in the optimized length group were reduced by 18.2% (P=0.01), 37% (P=0.003), 17.5% (P=0.013) and 13.3% (P=0.021) respectively. Compared with the optimized length group, the ED was reduced by 87%, preoperative positioning, intraoperative guidance and postoperative review DLP were also reduced by 88%, total milliampere second was reduced by 79%, with an average CTDIvol was reduced by 86%, in the low-dose optimized length group (P<0.001 for all).ConclusionOptimizing the length during CT scanning can effectively reduce the intraoperative radiation dose and reduce the operation time compared with conventional plan; low-dose and optimized length CT scan can further reduce the total radiation dose compared with optimized length group with no differences on intraoperative complications, biopsy results and operation time.  相似文献   
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