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Introduction

Total 25-hydroxyvitamin D [25(OH)D] is the most reliable indicator of vitamin D status. In this study, we compared two automated immunoassay methods, the Abbott Architect 25-OH Vitamin D assay and the Roche Cobas Vitamin D total assay, with the liquid chromatography-tandem mass spectrometry (LC-MS/MS).

Materials and methods

One hundred venous blood samples were randomly selected from routine vitamin D tests. Two of the serum aliquots were analyzed at the Abbott Architect i2000 and the Roche Cobas 6000’s module e601 in our laboratory within the same day. The other serum aliquots were analyzed at the LC-MS/MS in different laboratory. Passing-Bablok regression analysis and Bland-Altman plot were used to compare methods. Inter-rater agreement was analyzed using kappa (κ) analysis.

Results

The Roche assay showed acceptable agreement with the LC-MS/MS based on Passing-Bablok analysis (intercept: -5.23 nmol/L, 95% CI: -8.73 to 0.19; slope: 0.97, 95% CI: 0.77 to 1.15). The Abbott assay showed proportional (slope: 0.77, 95% CI: 0.67 to 0.85) and constant differences (intercept: 17.08 nmol/L; 95% CI: 12.98 to 21.39). A mean bias of 15.1% was observed for the Abbott and a mean bias of -14.1% was observed for the Roche based on the Bland-Altman plots. We found strong to nearly perfect agreement in vitamin D status between the immunoassays and LC-MS/MS. (κ: 0.83 for Abbott, κ: 0.93 for Roche) using kappa analysis.

Conclusion

Both immunoassays demonstrated acceptable performance, but the Roche Cobas assay demonstrated better performance than the Abbott Architect in the studied samples.Key words: 25-Hydroxyvitamin D, chromatography, immunoassay, methods, tandem mass spectrometry  相似文献   
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We examined the tracking of physical activity (PA) measured by accelerometers and subjective self- and parental reports in normal weight and overweight and obese pubertal boys over two-year period. In total, 156 boys with mean (±SD) age of 11.53 ± 0.76 at baseline and with mean age of 13.94 ± 0.74 at 2 year follow-up were studied. At baseline and approximately two years later, the boys completed self-report questionnaire and wore an accelerometer for seven consecutive days. On the basis of first year assessment’s body mass index (BMI), the children were grouped as normal weight and overweight and obese groups according to BMI cut-offs. Tracking correlations of objectively measured PA and subjectively measured PA were fairly similar across the 12–14 year-old-boys weight groups over two year period. Tracking correlations of objectively measured PA and subjectively measured PA were not significantly different over two-year period between both BMI groups. The results of the study show that pubertal boys objectively measured PA decreased over two-year period and so the boys started to be less active in their pubertal period.  相似文献   
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This paper describes a newly adapted instrument for measuring novice-to-expert-like perceptions about biology: the Colorado Learning Attitudes about Science Survey for Biology (CLASS-Bio). Consisting of 31 Likert-scale statements, CLASS-Bio probes a range of perceptions that vary between experts and novices, including enjoyment of the discipline, propensity to make connections to the real world, recognition of conceptual connections underlying knowledge, and problem-solving strategies. CLASS-Bio has been tested for response validity with both undergraduate students and experts (biology PhDs), allowing student responses to be directly compared with a consensus expert response. Use of CLASS-Bio to date suggests that introductory biology courses have the same challenges as introductory physics and chemistry courses: namely, students shift toward more novice-like perceptions following instruction. However, students in upper-division biology courses do not show the same novice-like shifts. CLASS-Bio can also be paired with other assessments to: 1) examine how student perceptions impact learning and conceptual understanding of biology, and 2) assess and evaluate how pedagogical techniques help students develop both expertise in problem solving and an expert-like appreciation of the nature of biology.  相似文献   
87.
基于显微图像的金标试纸条测试线线宽参数的测量方法具备操作方便、测量速度快、分辨率高等优点,然而图像采集系统采集到的金标试纸条的显微图像不可避免地会发生倾斜,这为后续的图像分割和参数测量带来了困难,因此需要对倾斜的金标试纸条显微图像进行校正。根据霍夫变换法和最小二乘法在直线检测中的优点和适用条件,拟采用一种结合霍夫变换法和最小二乘法的直线检测算法来求得金标试纸条图像的边缘线和边缘线的倾斜角度参数,并采用图像旋转变换算法实现对原图像的倾斜校正。实验表明,所采用的倾斜校正算法具备计算量小、占用内存小、校正精度高的优点,通过倾斜校正可以准确测量倾斜金标试纸图像的线宽参数。  相似文献   
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The aim of the present study is to conduct a systematic review research which focuses on research studies into the school practicum. In order to identify the main issues and also to provide a contemporary picture of practicum, 114 studies published on the topic are reviewed and analysed in terms of: (i) aims, (ii) main participants, (iii) methodology used and (iv) the main outcomes emerging. Many of the reviewed studies take pre-service teachers as their main participants. The review also shows that many practicum studies are relatively small-scale studies since they are mainly qualitative focused and findings derived from a relatively small sample. This suggests that more large-scale studies are needed in the field in order to provide greater insight into teaching practicum. Finally, this systematic review provides some food for thought in the area of practicum research and promotes further studies in this complex field.  相似文献   
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Phonics, fluency, and reading strategy trainings are evidence-based interventions that foster the reading skills of poor readers in primary school. The purpose of the present study was to compare differential effects of the three types of trainings on the efficiency of component processes on word, sentence, and text level immediately after the training and at a 3-month follow-up. The 235 poor readers were randomly allocated to one of the reading interventions or to a control condition. All interventions consisted of 25 sessions that were scheduled twice a week and lasted 45 min. Results indicated short-term effects of the phonics training and the strategy training on the efficiency of a broad range of word-level and sentence-level processes. None of the treatment effects persisted over the long term, indicating the need for instructional efforts to regularly practice the acquired skills after the actual training.  相似文献   
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