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61.
62.
Cutaneous angiosarcoma (CAS) is a rare soft tissue sarcoma with rapid growth and poor prognosis. We retrospectively analyzed the data of 18 patients with CAS who underwent 18F‐Fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) at the initial visit to the Department of Dermatology, Okayama University Hospital from September 2006 to March 2016. In the univariate survival analysis, patients with high standardized uptake values (SUVmax) of the primary tumor showed significantly poorer prognosis than those with low SUVmax. Early assessment of prognosis using PET/CT may predict patient survival and is useful in the selection of therapeutic strategies.  相似文献   
63.
BackgroundThe abnormal alcohol consumption could cause toxicity and could alter the human brain’s structure and function, termed as alcohol used disorder (AUD). Unfortunately, the conventional screening methods for AUD patients are subjective and manual. Hence, to perform automatic screening of AUD patients, objective methods are needed. The electroencephalographic (EEG) data have been utilized to study the differences of brain signals between alcoholics and healthy controls that could further developed as an automatic screening tool for alcoholics.MethodIn this work, resting-state EEG-derived features were utilized as input data to the proposed feature selection and classification method. The aim was to perform automatic classification of AUD patients and healthy controls. The validation of the proposed method involved real-EEG data acquired from 30 AUD patients and 30 age-matched healthy controls. The resting-state EEG-derived features such as synchronization likelihood (SL) were computed involving 19 scalp locations resulted into 513 features. Furthermore, the features were rank-ordered to select the most discriminant features involving a rank-based feature selection method according to a criterion, i.e., receiver operating characteristics (ROC). Consequently, a reduced set of most discriminant features was identified and utilized further during classification of AUD patients and healthy controls. In this study, three different classification models such as Support Vector Machine (SVM), Naïve Bayesian (NB), and Logistic Regression (LR) were used.ResultsThe study resulted into SVM classification accuracy = 98%, sensitivity = 99.9%, specificity = 95%, and f-measure = 0.97; LR classification accuracy = 91.7%, sensitivity = 86.66%, specificity = 96.6%, and f-measure = 0.90; NB classification accuracy = 93.6%, sensitivity = 100%, specificity = 87.9%, and f-measure = 0.95.ConclusionThe SL features could be utilized as objective markers to screen the AUD patients and healthy controls.  相似文献   
64.
65.
基于自由变形法的多模态医学图像的配准与融合   总被引:3,自引:0,他引:3  
本研究提出了一种自动识别颈部PET-CT图像特征点的算法,它应用自由变形(FFD)方法以CT图像的特征点为参考使PET图像产生变形,再结合最大互信息法对颈部PET与CT图像进行非刚体配准,最后用改进的小波图像融合法把两者进行融合得出视觉效果比较理想的融合图像。经实际计算得出的变形PET图像与对应CT图像的互信息量大于原始PET图像,并且最后用改进的小波图像融合法得出的融合图像的信息量比一般小波融合大,由此证明本研究所用方法是有效的。  相似文献   
66.

Background

Females exhibit significantly greater incidence, prevalence, and severity of osteoarthritis (OA) compared to males. Despite known biological, morphological, and functional differences between males and females, there has been little sex-related investigation into sex-specific biomechanical and neuromuscular responses to OA.

Objective

To identify sex-related differences in OA-affected adults and within-sex differences between healthy and OA-affected adults' muscular activation patterns during lower limb loading.

Methods

Thirty adults with OA and 36 controls completed a standing ground reaction force (GRF) matching protocol requiring participants to expose equal body weight to each leg and modulate horizontal GRFs while maintaining constant joint positions. Electromyography was plotted as a function of GRF direction to depict muscle activation patterns. Muscles were classified as a general joint stabilizer, specific joint stabilizer or moment actuator by quantifying activation patterns with a test of asymmetry, specificity index and mean direction of activity. Lower limb kinematics and kinetics were also recorded.

Results

In general, muscle roles as it relates to joint stability did not differ between groups. Compared to controls, both males and females with OA demonstrated greater rectus femoris activity and reduced knee rotation moments. Females with OA had significantly greater biceps femoris and gastrocnemius activity during respective lateral, and anterior–medial loading directions compared to males with OA.

Conclusions

We identified fundamental differences in muscular stabilization strategies in older adults with OA as well as sex-related changes in neuromuscular function that may influence joint loading conditions and provide insight into the greater incidence of knee OA in females.  相似文献   
67.

Objective

In Japan, the human papillomavirus (HPV) vaccination rate has sharply fallen to nearly 0% due to sensational media reports of adverse events. Online anti-HPV-vaccination activists often warn readers of the vaccine’s dangers. Here, we aimed to examine frequently appearing contents on pro- and anti-HPV vaccination websites.

Methods

We conducted online searches via two major search engines (Google Japan and Yahoo! Japan). Targeted websites were classified as “pro,” “anti,” or “neutral” according to their claims, with the author(s) classified as “health professionals,” “mass media,” or “laypersons.” We then conducted a text mining analysis.

Results

Of the 270 sites analyzed, 16 contents were identified. The most frequently appearing contents on pro websites were vaccine side effects, preventable effect of vaccination, and cause of cervical cancer. The most frequently appearing contents on anti websites were vaccine side effects, vaccine toxicity, and girls who suffer from vaccine side effects. Main disseminators of each content according to the author’s expertise were also revealed.

Conclusion

Pro-HPV vaccination websites should supplement deficient contents and respond to frequent contents on anti-HPV websites.

Practice implications

Effective tactics are needed to better communicate susceptibility to cervical cancer, frequency of side effects, and responses to vaccine toxicity and conspiracy theories.  相似文献   
68.
This paper concerns several important points when testing for Hardy-Weinberg equilibrium (HWE) and linkage disequilibrium (LD) in genetics. First, we challenge the necessity of using exclusively two-sided tests for LD. Next, we show that the exact 2-sided tests based on the most popular measures of LD are not equivalent, and neither are the standard statistical tests even though the 1-sided tests are equivalent. We show how this results in different inference about LD for two data sets consisting of small groups of markers. Finally, we advocate the use of the conditional p-value for both LD and HWE testing. An important advantage of this p-value is that equivalent 1-sided tests are transformed into equivalent 2-sided tests.  相似文献   
69.
This article concerns the asymptotic properties of linkage tests for affected‐sib‐pair data under the null hypothesis of no linkage. We consider a popular single‐locus analysis model where the unknown parameters are the disease allele frequency, the three penetrances for the three genotypes at the disease locus, and the recombination fraction between the marker locus and the disease locus. These parameters are completely confounded under the null hypothesis of no linkage. We show that 1) If the total variance of the trait (i.e., the additive variance plus the dominance variance) is “separated” from 0, then the likelihood ratio statistic has an asymptotic 0.5χ20+ 0.5χ21 distribution; 2) If the prevalence of the trait is “separated” from 0 and the recombination fraction is fixed at 0, then the likelihood ratio statistic has an asymptotic distribution which is a mixture of χ20, χ21 and χ22 . The implications of these results are discussed.  相似文献   
70.
目的研究应用力学因素检测膝关节功能方法的有效性.方法利用测力平台测量得到人体下肢在运动过程中的力学曲线,用数学方法确定力学曲线的最大值F和曲线特征值R.结果给出51例骨关节炎患者的分析数据,并给出30例正常人的结果作为对照.结论应用力学因素可以有效地检测膝关节功能状态.  相似文献   
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