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961.
Zoltán L?csei István Szabolcs Károly Rácz Gábor L. Kovács Dóra Horváth Erzsébet Toldy 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2012,22(3):365-370
High concentration of thyroglobulin antibodies (TgAb) is a major limiting factor of thyroglobulin measurements in patients with differentiated thyroid cancer. We investigated whether thyroglobulin antibody added to serum samples could interfere with the thyroglobulin assay. Thyroglobulin levels in serum samples with different concentrations of thyroglobulin were measured by electrochemiluminescence immunoassay before and after the addition of increasing concentrations of thyroglobulin antibody using the secondary calibrator solution of the thyroglobulin assay kit containing sheep thyroglobulin antibody to reach thyroglobulin antibody levels within or near to the reference range. Thyroglobulin and thyroglobulin antibody concentrations were also measured in 134 serum samples from 27 patients after thyroid ablation. There was a strong negative association (slope = −1.179) between thyroglobulin antibody and thyroglobulin concentrations in samples with added thyroglobulin antibody (beta = −0.86; P < 0.001). Changes in thyroglobulin concentrations were described mathematically as loss of thyroglobulin% = −0.2408 × Ln(thyroglobulin antibody IU/ml) + 0.1944. Thyroglobulin concentrations were significantly lower than those calculated from experiments with added thyroglobulin antibody in 26/134 samples from patients after thyroid ablation. We conclude that if the same TgAb interference exists in the presence of naturally occurring human TgAb, our observation may prove to be useful during follow-up of patients with differentiated thyroid cancer. However, further studies are needed to explore the clinical relevance of thyroglobulin antibody levels within or near to the reference range in monitoring these patients. 相似文献
962.
Katja Uhlig Bj?rn Boysen Andreas Lankenau Magnus Jaeger Erik Wischerhoff Jean-Fran?ois Lutz André Laschewsky Claus Duschl 《Biomicrofluidics》2012,6(2)
Thermoresponsive polymer surface coatings are a promising tool for cell culture applications. They allow for a mild way of cell detachment that preserves the activity of membrane proteins—a prerequisite for reliable cell analysis. To enlarge the application range of these coatings to cells with different adhesion properties, we synthesized various novel poly(ethylene glycol)-based thermoresponsive polymers and describe how (i) their chemical structure and (ii) their surface density affect their efficiency. In order to quantify the influence of both factors, the time for cell spreading and rounding efficiency were observed. As a result, efficiency of cell rounding, which is closely correlated to cell detachment, is less affected by both factors than the time needed for cell spreading. This time can effectively be adjusted by the molecular architecture which includes the length of the polymer backbone and the side chains. Based on this work, recommendations are given for future optimization of functionality of thermoresponsive polymer coatings for cell culture applications. 相似文献
963.
Dragan Antić Bratislav Danković Saša Nikolić Marko Milojković Zoran Jovanović 《Journal of The Franklin Institute》2012,349(1):323-336
In this paper, we define a class of almost orthogonal rational functions of Legendre type in a new manner. Relations of these functions with classical exponentional functions orthogonal over interval (0, ∞), as well as classical polynomials orthogonal over (0, 1) are explained. Defining relations of these functions can be used for designing almost orthogonal filters. These filters are generators of orthogonal signals and can be successfully applied in finding the best signal approximation in the sense of the mean square error. The filters orthogonal property enables building of physical (in this case electrical) models of dynamical systems (the sources of signals to be approximated) either with less components for the same model accuracy or higher accuracy for the same number of components than the other known models. New filters represent further improvement of previously designed filters, by the same authors, in the sense of simplicity, higher accuracy, lesser approximation time and even a possibility to approximate signals generated by systems with built-in imperfections. Series of experiments were performed to analyze the dependence of approximation accuracy and the number of filters sections. 相似文献
964.
965.
Animated models explicating how a problem is solved and why a particular method is chosen are expected to be effective learning
tools for novices, especially when abstract cognitive processes or concepts are involved. Cognitive load theory was used to
investigate how learners could be stimulated to engage in genuine learning activities. It was hypothesized that illusion of
control would impede transfer performance compared to a condition without illusion of control. Moreover, we hypothesized that
learners who first studied an animated model and then solved the same problem would perform better on transfer than learners
who studied the same animated model twice or who first solved the problem and then studied the animated model. In a 2 × 3
factorial experiment (N = 90) with the factors illusion of control (yes vs. no) and instruction method (study–practice, practice–study, study–study) only the first hypothesis was confirmed. Implications for the design of animated
models are discussed. 相似文献
966.
967.
Anne-Marie Nu?ez Elizabeth Murakami Ramalho Kimberley K. Cuero 《Innovative Higher Education》2010,35(3):177-190
Three female tenure-track faculty members at a Hispanic-Serving Institution explored how their cultural backgrounds inform
their pedagogical approaches toward equity. They drew upon Mills’s (1959) and Collins’s (1993) frameworks to examine how their personal biographies, local social contexts, and broader systemic institutions affect their
teaching processes for diverse students. These teaching processes include limiting assumptions about students, encouraging
students to consider their own personal biographies in relation to the social world, welcoming students’ multiple modes of
expression, serving as role models, and challenging inequities in schooling. They conclude with recommendations for enhancing
inclusivity in student learning and faculty development. 相似文献
968.
969.
Roger Johansson ?sa Wengelin Victoria Johansson Kenneth Holmqvist 《Reading and writing》2010,23(7):835-851
In this paper we explored text production differences in an expository text production task between writers who looked mainly
at the keyboard and writers who looked mainly at the monitor. Eye-tracking technology and keystroke-logging were combined
to systematically describe and define these two groups in respect of the complex interplay between text production and the
reading of one’s own emerging text. Findings showed that monitor gazers typed significantly faster and were more productive
writers. They also read their own text more, and they frequently read in parallel with writing. Analysis of fixation durations
suggests that more cognitive processing is in use during reading in parallel with writing than during reading in pauses. Keyboard
gazers used the left and right cursor keys significantly more. We suggest that this is because they revised their texts in
a much more serial mode than monitor gazers. Finally, analysis of the characteristics of the final texts showed no differences
between the groups. 相似文献
970.