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101.
《Sleep medicine》2021
ObjectiveThe Biological Rhythms Interview of Assessment in Neuropsychiatry (BRIAN) might be applicable for assessing delayed sleep-wake phase disorder (DSWPD). We aimed to investigate the reliability and validity of the Japanese version of the BRIAN self-report (J-BRIAN-SR) in DSWPD patients and determine a cutoff score to identify the presence of the disorder.MethodsWe enrolled 60 newly diagnosed DSWPD outpatients and 64 age-matched healthy controls. We used Cronbach's alpha for internal reliability to evaluate J-BRIAN-SR. We confirmed the reliability of the A test and re-test using Pearson's correlation coefficient in the controls. We used confirmatory factor analysis to evaluate the factor structure of J-BRIAN-SR and referenced the Morningness-Eveningness Questionnaire (MEQ) to check concurrent validity. We analyzed the receiver operating characteristic curve (ROC) to determine the J-BRIAN-SR cutoff point for the presence of DSWPD.ResultsThe 18-component scores of the J-BRIAN-SR had an overall reliability coefficient (Cronbach's alpha) of 0.82. We confirmed a high test-retest reliability using an intraclass correlation coefficient (r = 0.84). The correlation between J-BRIAN-SR and MEQ was 0.38 (p = 0.003). The J-BRIAN-SR that we extracted by exploratory factor analysis consisted of three factors. A score of 40 points provided a sensitivity of 80.0% and a specificity of 75.6% for the positivity of DSWPD.ConclusionsThe results of the present study revealed that J-BRIAN-SR is a valid and reliable instrument for screening and evaluating the severity of DSWPD. Our findings will be useful to physicians and patients in Japan and those in clinical settings. 相似文献
102.
103.
《Diagnostic and interventional imaging》2019,100(6):363-370
PurposeTo assess the variability of liver stiffness measurements using magnetic resonance elastography (MRE) at 1.5 T, depending on different approaches of regions of interest (ROIs) drawing.Material and methodsFifty consecutive patients with successful liver MRE were included. There were 32 men and 18 women with a mean age of 52 ± 14 (SD) years (range: 20–85 years). MRE was acquired using a gradient recalled-echo MRE sequence. At the level of the portal bifurcation, one observer drawn in the right liver first 3 elliptical ROI and then one free-hand ROI, as large as possible based on the confidence map and the anatomy. Three additional elliptical ROIs were further drawn on the slice above and 3 other on the slice below, for a total of 9 elliptical ROIs. The average value of liver stiffness in the 3 elliptical ROIs of the central slice and the one from the 9 elliptical ROIs were computed. Three liver stiffness values were obtained for each patient from the 3 measurement methods (one free-hand ROI, 3 elliptical ROIs and 9 elliptical ROIs). Inter-method variability was assessed using the intra-class correlation coefficient (ICC) and Bland-Altman analysis.ResultsThe variability between the 3 methods was excellent with ICC > 0.978 (P < 0.0001). The Bland-Altman analysis revealed high agreement between the 3 methods with bias < 0.45 kPa and limits of agreement < ±1.13 kPa. The variability was lower when comparing a large free-hand ROI and the 3-elliptical ROIs, than when comparing the 9-elliptical ROIs to one of the other methods.ConclusionOur results show that the variability between the 3 methods of ROI drawing and placement is very low. 相似文献
104.
105.
《Gait & posture》2020
BackgroundUnconstrained limits of stability assessment reveals aspects of volitional postural sway control that are inaccessible by other means. Prior versions of this assessment include instructions to sway towards predefined targets, and may not capture the full capability of the individual.Research questionThis study sought to establish the test-retest reliability of a novel limits of stability protocol.MethodsVolitional sway area was determined during unconstrained trials, where participants were instructed to explore their ability to sway towards the perimeter of their base of support. Visual feedback was provided via computer monitor. Forty healthy young adults (mean age = 20.2 ± 1.3, 15 males, 25 females) participated in this study. Trials were collected in three sessions, repeated at the same time of the same day, with one week between. Reliability was assessed using IntraClass Correlation Coefficients (ICC), considering the total area of sway as well as quadrant level area.ResultsReliability was moderate between the first and second session (0.583), and much higher 0.921) between the second and third session. The quadrant level reliability was poor to excellent (0.183−0.791), with similar trends between the three sessions.SignificanceUltimately, these results indicate that the novel limits of stability test is reliable. However, it is recommended that a practice trial be conducted prior to baseline establishment. 相似文献
106.
107.
BackgroundSmoking is a poor prognostic factor for healing after rotator cuff repair and is associated with inferior results. We hypothesized that smokers would have higher recurrent tear rates and more postoperative myotendinous junction (MTJ) retraction in healed repairs than nonsmokers three months postoperatively.MethodsRotator cuff repairs (RCRs) were retrospectively reviewed over a 2-year period. Patients underwent magnetic resonance imaging (MRI) within 6 months prior to surgery and again at 3 months postoperatively. Seventy-nine patients were included and stratified by smokers versus nonsmokers. Baseline patient demographics, tear characteristics, and surgical factors were collected. Preoperative and postoperative MRIs were assessed to quantify the MTJ position and to establish the recurrent tear rate.ResultsFor the total cohort (nonsmokers, n = 56; smokers, n = 23), significant differences in age, race, and traumatic onset of injury existed between groups. There were no significant differences in recurrent tear between smokers (26%) and nonsmokers (27%), but nonsmokers were more satisfied. For patients with healed RCRs (nonsmokers, n = 41; smokers, n = 17), there were significant differences in race. On univariate analysis, nonsmokers had a significantly more lateral MTJ postoperatively (P = 0.05). On multivariable regression analysis, medialized postoperative MTJ position in healed cuffs was driven only by greater preoperative rotator cuff retraction preoperatively. There were no significant differences in MTJ position based on smoking status for patients with healed RCRs.ConclusionSmoking does not appear to be an independent risk factor for postoperative MTJ retraction in healed RCRs, also known as failure in continuity. Preoperative tear size and retraction play the biggest roles in predicting postoperative MTJ position, regardless of smoking status. There are no significant differences in patient-reported outcomes for patients with healed RCRs, but nonsmokers had more satisfaction following RCR in the total cohort.Level of EvidenceLevel III; Retrospective cohort study; Diagnostic study 相似文献
108.
目的:在医学物理学实验教学中,设计性实验内容的不确定性,需要实验方法的多样性,需要相关仪器设备的多样性,而各医学院校在医学物理学实验设备的投入上都不多,那我们如何立足现有仪器设备,自己动手,勇于创新,对其从新组合.从而保证设计性实验顺利完成,进行了有益的尝试。方法:立足现有仪器设备,用弹簧、读数显微镜代替焦利称.采用拉脱法和用一个新的测量液体表面张力系数的方法一相对法测量,使液体表面张力系数随浓度变化的研究获得了满意的结果。结果:该实验具有操作简单,待测量少,结果明显的特点,为表面张力系数的测量提供了一种简易可行的方法。结论:在现有仪器设备条件下,通过我们摸索、创新,可以组合出新设备,找到实验的新方法,保证医学物理学实验教学的顺利进行。 相似文献
109.
The concentrations and distributions of the activity of natural radionuclides in soil samples were investigated in fifteen soil samples at El-Gor area representing two profiles (A and B) using a HP–Ge detector and alpha counting by SSNTD (CR-39), respectively. The average concentrations of the radionuclides 238U, 226Ra, 235U, 232Th and 40K are 203.4, 177.23, 9.77, 43.33 and 386.22 Bq kg−1 (dry weight), respectively, and profile A and 238U, 226Ra, 235U, 232Th and 40K have average concentrations of 232.58, 246, 11.7, 31.7, and 277.07 Bq kg−1 for profile B, respectively. The eTh and eU were estimated to detect the migration process of uranium into or out of an area or uranium to or from the studied profiles. The results indicate a migration of uranium by 29% for profile A and 65.37% for profile B. The activity ratio (238U/226Ra) was found to be 0.9 in profile A and 1.15 in profile B. These ratios coincide with the uranium migration processes. The responsible mass corresponding to the measured 226Ra activity was also calculated. The radon activity concentrations for the two profiles are nearly 300 Bq m−3. The emanation coefficient (η) was calculated from the ratio of the expected radon activity to the measured radon for the studied soil samples. The value of η was found to depend only on the radium activity regardless to soil formation. 相似文献