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91.
We performed detailed genetic analysis of the VP4/VP2 coding region in human rhinovirus species A to C (HRV-ABC) strains detected in patients with a variety of acute respiratory infections in Kumamoto, Japan in the period 2011–12. The phylogenetic tree and evolutionary timescale were obtained by the Bayesian Markov chain Monte Carlo method. Phylogenetic analyses showed that the present HRV-A, -B, and -C strains belonged to 25, 4, and 18 genotypes, respectively. Some new genotypes were confirmed as prevalent strains of HRV-C. An ancestor of the present HRV-ABCs could be dated back to about 20,000 years ago. The present HRV-A and -C strains have wide genetic divergence (pairwise distance >0.2) with rapid evolutionary rates (around 7 × 10−4 to 4 × 10−3 substitutions/site/year). Over 100 sites were found to be under negative selection, while no positively selected sites were found in the analyzed region. No evidence of recombination events was found in this region of the present strains. Our results indicate that the present HRV strains have rapidly evolved and subsequently diverged over a long period into multiple genotypes. 相似文献
92.
93.
《Injury》2018,49(6):1149-1154
PurposeADAPT is a fluoroscopic computer-assisted surgery system which intraoperatively shows the distance from the tip of the screw to the surface of the femoral head, tip-to-head-surface distance (TSD), and the tip-apex distance (TAD) advocated by Baumgaertner et al. The study evaluated the accuracy of ADAPT.Patients and methodsA total of 55 patients operated with ADAPT between August 2016 and March 2017 were included as subjects. TSD and TAD were measured postoperatively using computed tomography (CT) and X-rays. The intraclass correlation coefficient (ICC) was checked in advance. The error was defined as the difference between postoperative and intraoperative measurement values of ADAPT. Summary statistics, root mean square errors (RMSEs), and correlations were evaluated.ResultsICC was 0.94 [95% CI: 0.90–0.96] in TSD and 0.99 [95% CI: 0.98–0.99] in TAD. The error was −0.35 mm (−1.83 mm to 1.12 mm) in TSD and +0.63 mm (−5.65 mm to 4.59 mm) in TAD. RMSE was 0.63 mm in TSD and 1.53 mm in TAD. Pearson’s correlation coefficient was 0.79 [95% CI: 0.66–0.87] in TSD and 0.83 [95% CI: 0.72–0.89] in TAD. There were no adverse events with ADAPT use.ConclusionADAPT is highly accurate and useful in guiding surgeons in properly positioning the screws. 相似文献
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95.
在腹腔镜模拟训练过程中,研究不同训练模式下被测试者的注视策略,探索腹腔镜训练的新模式。被测试者被随机分为无指导组,视频学习组和专家指导组进行左右移环任务。利用Tobii X1 Light型眼动仪调用模拟训练箱中的摄像头,采集受试者的眼动数据。通过对数据处理分析,计算注视点个数,平均注视时间,注视时间百分比,扫描距离指标。与对照组相比,视频学习和专家指导模式下,任务完成时间降低23%,扫描距离缩短25%,注视点个数减少17%,平均注视时间没有显著差异。视频组和专家指导组之间无明显差异。结果表明不同学习模式下,被测试者的注视行为有明显差异。视频学习和专家指导下效果更好,可以用专家操作时的注视点视频指导初级训练者进行训练。 相似文献
96.
背景与目的:乳腺癌手术方式的选择受到诸多因素影响,本研究旨在分析乳腺癌患者选择乳房重建手术的影响因素,重点探讨居住地距离与乳房重建的关系。方法:回顾性分析了1999年1月—2015年12月复旦大学附属肿瘤医院收治的因单侧或双侧0~Ⅱ期乳腺癌行全乳切除术的女性患者临床资料,分析居住地距离与乳房重建比例的关系。结果:非上海患者选择全乳切除术后乳房重建比例高于上海患者(6.1% vs 4.5%,P<0.001)。居住地距离影响乳房重建比例(P=0.035)。单因素分析显示,居住地距离越远,选择乳房重建手术比例越高,而年龄、体质量指数(body mass index,BMI)、TNM分期与乳房重建的选择呈负相关(P均<0.001)。多因素分析显示,年龄增长、BMI增加、TNM分期较晚是拒绝行乳房重建的独立影响因素(P均<0.001),而居住地距离不是乳房重建的独立影响因素(P>0.05),且与具体乳房重建方式无交互作用。年龄与居住地距离呈负相关(P<0.001)。结论:乳腺癌患者的居住地距离与乳房重建比例呈线性相关;年龄、BMI和疾病分期是影响乳房重建的主要因素。 相似文献
97.
98.
《Journal of medical engineering & technology》2013,37(4):264-272
AbstractMyocardial infarction (MI) is a coronary artery disease acquired due to the lack of blood supply in one or more sections of the myocardium, resulting in necrosis in that region. It has different types based on the region of necrosis. In this paper, a statistical approach for classification of Anteroseptal MI (ASMI) is proposed. The first step of the method involves noise elimination and feature extraction from the Electrocardiogram (ECG) signals, using multi-resolution wavelet analysis and thresholding-based techniques. In the next step a classification scheme is developed using the nearest neighbour classification rule (NN rule). Both temporal and amplitude features relevant for automatic ASMI diagnosis are extracted from four chest leads v1–v4. The distance metric for NN classifier is calculated using both Euclidian distance and Mahalanobis distance. A relative comparison between these two techniques reveals that the later is superior to the former, as evident from the classification accuracy. The proposed method is tested and validated using the PTB diagnostic database. Classification accuracy for Mahalanobis distance and Euclidean distance-based NN rule are 95.14% and 81.83%, respectively. 相似文献
99.
100.
《Gaceta sanitaria / S.E.S.P.A.S》2016,30(4):304-307
ObjectiveTo analyze the relationship between nutritional status measured by anthropometry and the mental, psychomotor and language development of infants in marginalized rural areas of Mexico.MethodCross-sectional study with 576 infants aged from 7 to 26 months in four rural locations. Variables consisted of measures of anthropometric and cognitive development.ResultsInfants with short stature had a lower rate of language development, while birth weight was marginally associated with psychomotor development.ConclusionAlthough acute malnutrition (identified by underweight) is no longer a problem in rural areas of Mexico, chronic malnutrition (expressed as stunting) is still common and is associated with alterations in mental development in the child population. 相似文献