排序方式： 共有27条查询结果，搜索用时 31 毫秒
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Zuzana Svobodova Mohamad Reza Mohamadi Barbora Jankovicova Hermann Esselmann Romain Verpillot Markus Otto Myriam Taverna Jens Wiltfang Jean-Louis Viovy Zuzana Bilkova 《Biomicrofluidics》2012,6(2):024126-024126-12
Determination of amyloid β (Aβ) isoforms and in particular the proportion of the Aβ 1-42 isoform in cerebrospinal fluid (CSF) of patients suspected of Alzheimer’s disease might help in early diagnosis and treatment of that illness. Due to the low concentration of Aβ peptides in biological fluids, a preconcentration step prior to the detection step is often necessary. This study utilized on-chip immunoprecipitation, known as micro-immunoprecipitation (μIP). The technique uses an immunosorbent (IS) consisting of magnetic beads coated with specific anti-Aβ antibodies organized into an affinity microcolumn by a magnetic field. Our goal was to thoroughly describe the critical steps in developing the IS, such as selecting the proper beads and anti-Aβ antibodies, as well as optimizing the immobilization technique and μIP protocol. The latter includes selecting optimal elution conditions. Furthermore, we demonstrate the efficiency of anti-Aβ IS for μIP and specific capture of 5 Aβ peptides under optimized conditions using various subsequent analytical methods, including matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), capillary electrophoresis, microchip electrophoresis, and immunoblotting. Synthetic Aβ peptides samples prepared in buffer and spiked in human CSF were analyzed. Finally, on-chip immunoprecipitation of Aβ peptides in human CSF sample was performed. 相似文献
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The purpose of the present study was to investigate competitive anxiety during balance beam performance in gymnasts. Competitive anxiety was assessed continuously by heart rate monitoring and by retrospective self-report of nervousness in eight female national level gymnasts during their balance beam routine during one competition and two training sessions. A significant negative correlation was found between the score of the retrospective self-report of nervousness and performance during the routine. There were no significant differences in performance score by the judges between the three test sessions. There were also no differences in the retrospective self-report of nervousness. However, heart rate was significantly higher during the competition session than during the training sessions. The potential value of the retrospective report of nervousness for the study of critical events during gymnastic performance is illustrated. The results are discussed in the light of catastrophe theory. 相似文献
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The aim of this study was to determine the effects of Chinese martial arts practice on postural reaction control after perturbation. Participants standing in Romberg tandem posture were subjected to an unexpected lateral platform translation with the eyes open or closed at two translation amplitudes. The peak displacement of the centre of pressure and of the centre of mass, and the onset latency of muscular activity (tibialis anterior, gastrocnemius, lumbodorsal muscular group, and rectus abdominis), were evaluated for martial arts practitioners and for sport and non-sport participants. Compared with the sport and non-sport participants, the martial arts group showed lower maximal centre of pressure and centre of mass peak displacements in both the lateral and anterior - posterior directions, but no difference was found in the onset of muscular responses. We conclude that martial arts practice influences postural reaction control during a fixed-support strategy in a tandem task. The martial arts group used the ankle joint more frequently than the sport and non-sport participants, especially in the eyes-closed conditions. Our results suggest that the better balance recovery in the martial arts group is a consequence of better control of biomechanical properties of the lower limbs (e.g. through muscular response by co-contraction), not a change in the neuromuscular temporal pattern. 相似文献
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Jean-Louis Le Moigne 《European Journal of Engineering Education》1981,6(1-2):105-115
Were Heron of Alexandria and Vitruve model engineers? Or three centuries earlier, was Eupalinos glorified by Paul Valéry as an architect because he was an engineer? [1] From Greek mechanicians to Renaissance engineers [2] it is an illustrious line that western engineers can refer to. How many examples there are, how many witnesses! Their works, inspiration, methods and language are still marvellous models for the engineer today. 相似文献
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Jorge Cottyn Dirk De Clercq Jean-Louis Pannier Geert Crombez Matthieu Lenoir 《Journal of sports sciences》2013,31(2):157-164
Abstract The purpose of the present study was to investigate competitive anxiety during balance beam performance in gymnasts. Competitive anxiety was assessed continuously by heart rate monitoring and by retrospective self-report of nervousness in eight female national level gymnasts during their balance beam routine during one competition and two training sessions. A significant negative correlation was found between the score of the retrospective self-report of nervousness and performance during the routine. There were no significant differences in performance score by the judges between the three test sessions. There were also no differences in the retrospective self-report of nervousness. However, heart rate was significantly higher during the competition session than during the training sessions. The potential value of the retrospective report of nervousness for the study of critical events during gymnastic performance is illustrated. The results are discussed in the light of catastrophe theory. 相似文献
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Alexandra Ursache Rebecca Robbins Alicia Chung Spring Dawson-McClure Dimitra Kamboukos Esther J. Calzada Girardin Jean-Louis Laurie Miller Brotman 《Child development》2021,92(5):1932-1950
Children of color are more likely to have poor sleep health than White children, placing them at risk for behavioral problems in the classroom and lower academic performance. Few studies, however, have utilized standardized measures of both classroom behavior and achievement. This study examined whether children’s sleep (parent and teacher report) in first grade concurrently related to independent observations of classroom behavior and longitudinally predicted achievement test scores in second grade in a sample of primarily Black (86%) children (n = 572; age = 6.8) living in historically disinvested neighborhoods. Higher teacher-reported child sleepiness was associated with lower adaptive behaviors and higher problem behaviors in the classroom, and predicted lower achievement. Parent-reported bedtime resistance and disordered breathing also predicted lower achievement. 相似文献