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51.
52.

Introduction

Extremely high glucose concentrations have been shown to interfere with creatinine assays especially with Jaffe method in peritoneal dialysate. Because diabetes is the fastest growing chronic disease in the world, laboratories study with varying glucose concentrations. We investigated whether different levels of glucose spiked in serum interfere with 21 routine chemistry and thyroid assays at glucose concentrations between 17-51 mmol/L.

Materials and methods

Baseline (group I) serum pool with glucose concentration of 5.55 (5.44-5.61) mmol/L was prepared from patient sera. Spiking with 20% dextrose solution, sample groups were obtained with glucose concentrations: 17.09, 34.52, and 50.95 mmol/L (group II, III, IV, respectively). Total of 21 biochemistry analytes and thyroid tests were studied on Abbott c8000 and i2000sr with commercial reagents. Bias from baseline value was checked statistically and clinically.

Results

Creatinine increased significantly by 8.74%, 31.66%, 55.31% at groups II, III, IV, respectively with P values of < 0.001. At the median glucose concentration of 50.95 mmol/L, calcium, albumin, chloride and FT4 biased significantly clinically (-0.85%, 1.63%, 0.65%, 7.4% with P values 0.138, 0.214, 0.004, < 0.001, respectively). Remaining assays were free of interference.

Conclusion

Among the numerous biochemical parameters studied, only a few parameters are affected by dramatically increased glucose concentration. The creatinine measurements obtained in human sera with the Jaffe alkaline method at high glucose concentrations should be interpreted with caution. Other tests that were affected with extremely high glucose concentrations were calcium, albumin, chloride and FT4, hence results should be taken into consideration in patients with poor diabetic control.Key words: assay interference, glucose interference, preanalytical phase, creatinine, Jaffe kinetic assay, thyroid function tests  相似文献   
53.
从图论的角度讨论了静态最优路径的算法及其复杂度,在此基础上对停车诱导功能需求进行研究,提出了停车场内部诱导系统的设计思路和方法.  相似文献   
54.
Do preadolescent sport self-concepts influence subsequent sport performance? Longitudinal data (Grades 3, 4, and 6) for young boys and girls (N= 1,135; mean age = 9.67) were used to test reciprocal effects model (REM) predictions that sport self-concept is both a cause and a consequence of sport accomplishments. Controlling prior sport performance (performance-based measures and teacher assessments), prior sport self-concept had positive effects on subsequent sport performance in both Grade 4 and Grade 6 and for both boys and girls. Coupled with previous REM studies of adolescents in the academic domain, this first test for preadolescents in the sport domain supports the generalizability of REM predictions over gender, self-concept domain, preadolescent ages, and the transition from primary to secondary school.  相似文献   
55.
ABSTRACT

Relying on Marianne Hirsch’s work on postmemory, as well as theories about new media and memory, this study explores how a group of Armenian young adults in Toronto remember the Armenian Genocide from afar, 100 years after it happened. The data come from 100 Voices: Survival, Memory, Justice. Through a thematic and visual analysis of a sample of video clips posted on YouTube, this study argues that 100 Voices is a work of postmemory that stands at the intersection of prevailing ethno-nationalist constructions of Armenian identity on the one hand, and universal discourses of human rights and historical justice, on the other. Participants are positioned as the Armenian youth, performing a particular duty of memory to remember the genocide and transmit genocide memories to future generations. At the same time, 100 Voices enables these youths to emerge as activists who express their group-based claims through universal parameters of claim-making.  相似文献   
56.
"思想道德修养"课教学中增加心理健康教育的内容,运用心理学的原理、方法等进行教学,对于更好地体现德育内容,扩展其功能,提高该课的教学实效起到了积极的作用.  相似文献   
57.
58.
ABSTRACT

Background: Schoolchildren’s personality development is considered a central goal of physical education (PE). With regard to the relationship between psychological well-being and global self-esteem over the life course, the promotion of positive self-esteem is an issue of particular significance. Past research revealed that PE taught with an individualized teacher frame of reference (iTFR) and a reflexive teaching style is associated with positive effects on facets of children’s perceived sports competence. However, it remains an open question whether this teaching styles has the potential to promote positive self-esteem.

Purpose: The present study investigated whether a five-month teacher training, aimed to enhance the teachers’ iTFR and their reflexive teaching style in PE, has a positive effect on students’ perceived sports competence and their global self-esteem. To analyse the implementation quality, changes in students’ perceived iTFR and perceived reflexive teaching style were investigated.

Method: A total of 21 teachers were assigned to either an intervention group (n?=?13), receiving the five-month teacher training, or a control group (n?=?8) consisting of regular teaching without teacher training. The teacher training encompassed five three-hour consecutive sessions during which the teachers acquired theoretical and practical knowledge about the promotion of competence perceptions in PE with a reflexive teaching style and an iTFR. Between the sessions, the teachers were instructed to implement an iTFR and a reflexive teaching style into their own PE classes. To evaluate the effects of the teacher training, their students’ (N?=?315, 53.7% girls, Mage?=?13.2 y, SDage?=?1.3 y) perceived teaching style (iTFR and reflexive teaching), perceived sports competence and global self-esteem were measured with paper-pencil questionnaires at three measurement points (pre, post and follow-up).

Findings: Linear mixed effect models showed that students of the intervention group reported an increase in their teachers’ reflexive teaching style, but there were no changes with regard to iTFR. With regard to students’ perceived sports competence and global self-esteem, there were significant interaction effects between time and group over a period of eight months (from pre-test to follow-up), indicating positive effects on these self-concept dimensions due to the teacher training.

Conclusion: The present study indicates that a long-term teacher training supports PE teachers to implement teaching styles with the aim to promote students’ self-concept. Furthermore, the findings lead to the assumption that a more pronounced iTFR in combination with an enhanced reflexive teaching style has the potential to positively influence schoolchildren’s perceived sports competence and global self-esteem.  相似文献   
59.
The lower limb kinetics of curve sprinting in amputees are not well described in the literature, particularly with respect to the effect of the side of amputation. This is an issue due to the importance of the knowledge for prosthetic design and classification of athletes. Thus, the aim of this study was to investigate the influence of side of amputation on curve sprinting performance in athletes with a unilateral leg amputation. A three-dimensional motion analysis system (Vicon), four force plates (Kistler) and a modified mathematical human model (ALASKA) were used to compare clockwise and counter clockwise curve sprinting lower limb kinematics and kinetics of a Paralympic medalist with a left-sided knee exarticular amputation. Results reveal that vertical ground reaction force application and total vertical impulse were lower when the affected limb was at the inside of the curve. The unaffected limb showed joint mechanics different to those established for non-amputee athletes and might contribute better to propulsion when being the inside limb. Curve sprinting biomechanics and the ability to attain high radial velocities are directly dependent on the side of amputation relative to the curve direction in a unilateral amputee athlete of highest performance level.  相似文献   
60.
The purpose of this study was to examine CHO ingestion on a cognitive task using a field-simulated time-trial (TT) under hypoxia in well-trained triathletes. Ten male triathletes (age: 22.1 ± 1.1 years; VO2max: 59.4 ± 1.4 ml/kg/min) participated in this double-blind/crossover/counter-balanced design study. Participants completed 3 TT trials: 1) normoxic placebo (NPLA; FiO2 = 20.9%), 2) hypoxic placebo (HPLA; FiO2 = 16.3%), and 3) hypoxic CHO (HCHO; 6% CHO provided as 2 ml/kg/15 min; FiO2 = 16.3%). During the TT, physiological responses (SpO2, HR, RPE, and blood glucose/lactate), cognitive performance, and cerebral haemodynamics were measured. Hypoxia reduced TT performance by ~3.5–4% (p < 0.05), but CHO did not affect TT performance under hypoxia. For the cognitive task, CHO slightly preserved exercise-induced cognitive reaction speed but did not affect response accuracy during hypoxic exercise. However, CHO did not preserve the decreased Hb-Diff (cerebral blood flow, CBF) and increased HHb in the prefrontal lobe (p < 0.05) during hypoxic exercise, and CHO failed to preserve hypoxia-suppressed prefrontal CBF and tissue oxygen saturation. In conclusion, the present study demonstrates that CHO is effective in sustaining reaction speed for a cognitive task but not promoting TT performance during hypoxic exercise, which would be important for strategy-/decision-making when athletes compete at moderate high-altitude.  相似文献   
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