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51.
Abstract

Assessment in art is notoriously difficult and is probably best approached with skepticism. Artistry is notoriously difficult to assess. Yet measures of student learning in art are needed for both advocacy and art education policy. Assessments, particularly large-scale assessments, influence funding and educational policy at all levels. This article explores some of the challenges of assessment in the visual arts and critically examines the Advanced Placement Studio Art Portfolio to illustrate how a product-oriented assessment might influence teaching and policy.  相似文献   
52.
Free iron is capable of stimulating the production of free radicals which cause oxidative damage such as lipid peroxidation. One of the most important mechanisms of antioxidant defense is thus the sequestration of iron in a redox-inactive form by transferrin. In diabetes mellitus, increased oxidative stress and lipid peroxidation contribute to chronic complications but it is not known if this is related to abnormalities in transferrin function. In this study we investigated the role of transferrin concentration and glycation. The antioxidant capacity of apotransferrin to inhibit lipid peroxidation by iron-binding decreased in a concentration-dependent manner from 89% at <formula>≥2 mg/ml</formula> to 42% at 0.5 mg/ml. Pre-incubation of apotransferrin with glucose for 14 days resulted in a concentration-dependent increase of glycation: 1, 5 and 13 μmol fructosamine/g transferrin at 0, 5.6 and 33.3 mmol/l glucose respectively, p<0.001. This was accompanied by a decrease in the iron-binding antioxidant capacity of apotransferrin. In contrast, transferrin glycation by up to 33.3 mmol/l glucose did not affect chemiluminescence-quenching antioxidant capacity, which is iron-independent. Colorimetric evaluation of total iron binding capacity in the presence of an excess of iron (iron/transferrin molar ratio=2.4) also decreased from 0.726 to 0.696 and 0.585 mg/g transferrin after 0, 5.6 and 33.3 mmol/l glucose, respectively, p<0.01. In conclusion, these results suggest that lower transferrin concentration and its glycation can, by enhancing the pro-oxidant effects of iron, contribute to the increased lipid peroxidation observed in diabetes.  相似文献   
53.
《Free radical research》2013,47(10):1179-1189
Abstract

Aim of the present study was to test, by vitamin E treatment, the hypothesis that muscle adaptive responses to training are mediated by free radicals produced during the single exercise sessions. Therefore, we determined aerobic capacity of tissue homogenates and mitochondrial fractions, tissue content of mitochondrial proteins and expression of factors (PGC-1, NRF-1, and NRF-2) involved in mitochondrial biogenesis. Moreover, we determined the oxidative damage extent, antioxidant enzyme activities, and glutathione content in both tissue preparations, mitochondrial ROS production rate. Finally we tested mitochondrial ROS production rate and muscle susceptibility to oxidative stress. The metabolic adaptations to training, consisting in increased muscle oxidative capacity coupled with the proliferation of a mitochondrial population with decreased oxidative capacity, were generally prevented by antioxidant supplementation. Accordingly, the expression of the factors involved in mitochondrial biogenesis, which were increased by training, was restored to the control level by the antioxidant treatment. Even the training-induced increase in antioxidant enzyme activities, glutathione level and tissue capacity to oppose to an oxidative attach were prevented by vitamin E treatment. Our results support the idea that the stimulus for training-induced adaptive responses derives from the increased production, during the training sessions, of reactive oxygen species that stimulates the expression of PGC-1, which is involved in mitochondrial biogenesis and antioxidant enzymes expression. On the other hand, the observation that changes induced by training in some parameters are only attenuated by vitamin E treatment suggests that other signaling pathways, which are activated during exercise and impinge on PGC-1, can modify the response to the antioxidant integration.  相似文献   
54.
Exercise training has demonstrated cardioprotection effects. However, the exact mechanism behind this effect is not is clear. The present study evaluated the effects of 12 weeks of previous treadmill training on the levels of oxidative damage, antioxidant enzyme activity and injury in the myocardium of rats submitted to infarction induced by isoproterenol (ISO). Isoproterenol treatment (80 mg/kg given over 2 days in two equal doses) caused arrhythmias and 60% mortality within 24 h of the last injection in the control group (C + ISO) group when compared with the saline control group (saline). Creatine Kinase ? MB levels were markedly increased in hearts from ISO-treated animals in the C + ISO group. Twelve weeks of treadmill training reduced superoxide production, lipid peroxidation levels and protein carbonylation in these animals, as well as increasing the activities and expressions of SOD and CAT. Previous training also reduced CK-MB levels and numbers of deaths by 40%, preventing the deleterious effects of ISO. Based on the data obtained in this study, it is suggested that 12-week treadmill training increases antioxidant enzymes, decreases oxidative damage and reduces the degree of infarction induced by ISO in the hearts of male rats.  相似文献   
55.
《Free radical research》2013,47(6):662-671
Abstract

Advanced oxidation protein products (AOPP) as a biomarker of oxidative stress has been demonstrated in chronic kidney disease (CKD) patients; however, current methods to detect the accumulation of AOPP in serum and in tissues are limited and unreliable. This study generated a monoclonal antibody (mAb) designated 3F2, that reacts specifically with hypochlorous acid (HOCl)-modified proteins, but not with the native forms or with other types of oxidative modifications. Notably, mAb 3F2 recognizes the AOPP deposited in renal tissues of AOPP-treated rats and of patients with different kinds of CKD. Moreover, this mAb can almost completely inhibit the production of reactive oxygen species in RAW264.7 cells induced by AOPP (p < 0.001). In conclusion, mAb 3F2 can be used to detect AOPP specifically in serum and in tissues, and this antibody can potentially provide an important tool and new insight into research on diseases related to oxidative stress.  相似文献   
56.
To clarify changes of neutrophil functions, mental conditions and relationships among them, 19 male elite long‐distance runners participated in this study for 6 months. Examinations, with informed consent, were carried out once a month. According to the results of physical characteristics, it was thought that training intensity was reduced after the main race, Hakone‐Ekiden. Neutrophil functions were estimated by indices of reactive oxygen species production, determined by luminol‐ and lucigenin‐dependent chemiluminescence (LmCL and LgCL, respectively) and cytochrome c reduction methods. The peak times (PT) in LmCL and LgCL (LgPT) were most prolonged in January and December, respectively. The peak heights (PH) in LmCL (LmPH) were enhanced in February. Decreased levels of negative categories in the profile of mood state (POMS) questionnaire and the total mood state (TMS) of POMS were observed in February without significance. Correlation analysis using measured values revealed significant negative correlation between LmPH and negative categories in POMS; however, these correlations were possibly a mere appearance, caused by personal differences. After eliminating personal differences, LgPT correlated positively to depression (p < 0.05), anger (p < 0.05), fatigue (p < 0.01) and TMS (p < 0.05). These results suggest that the mean time from the recognition of foreign matter to the maximum production of superoxide from neutrophils is prolonged in the mentally suppressed conditions found under continuous physical training. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
57.
目的:分析早期强化步行基本功训练对脑卒中预后的影响。方法:选取我院2008年10月一2011年10月收治的176例恢复期脑卒中患者,按照随机数字表分为观察组及对照组,各88例,均接受常规药物治疗和康复训练,观察组在此基础上接受早期强化步行基本功训练,对比两组患者的预后。结果:两组患者治疗后FMA—LE、BBS及MBI评分均见上升,观察组较对照组上升程度更为明显(P〈0.05),T2时期观察组评分亦见升高,而对照组评分与T1时期相比无明显统计学差异(P〉0.05);两组患者治疗后步长、步宽及步速均见上升,观察组较对照组上升程度更为明显(P〈0.05),T2时期观察组步态参数亦见升高,而对照组步态参数与T1时期相比无明显统计学差异(P〉0.05)。结论:早期强化步行基本功训练能够有效改善脑卒中患者下肢运动功能和平衡能力,保证治疗后步行功能,避免生活质量下降,该康复方法值得广泛推广。  相似文献   
58.

Background and aims

Sustained interaction of advanced glycation end products (AGEs) with their receptor RAGE and subsequent signaling plays an important role in the development of diabetic complications. Genetic variation of RAGE gene may be associated with the development of vascular complications in type 2 diabetes mellitus (T2DM).

Objectives

The present study aimed to explore the possible association of RAGE gene polymorphisms namely − 374T/A, − 429T/C and G82S with serum level of AGEs, paraoxonase (PON1) activity and macro-vascular complications (MVC) in Indian type 2 diabetes mellitus patients (T2DM).

Methods

A total of 265 diabetic patients, including DM without any complications (n = 135), DM-MVC (n = 130) and 171 healthy individuals were enrolled. Genotyping of RAGE variants were assessed by polymerase chain reaction-restriction fragment length polymorphism. Serum AGEs were estimated by ELISA and fluorometrically. and PON1 activity was assessed spectrophotometrically.

Results

Of the three examined SNPs, association of − 429T/C polymorphism with MVC in T2DM was observed (OR = 3.001, p = 0.001) in the dominant model. Allele ‘A’ of − 374T/A polymorphism seems to confer better cardiac outcome in T2DM. Patients carrying C allele (− 429T/C) and S allele (G82S) had significantly higher AGEs levels. − 429T/C polymorphism was also found to be associated with low PON1 activity. Interaction analysis revealed that the risk of development of MVC was higher in T2DM patients carrying both a CC genotype of − 429T/C polymorphism and a higher level of AGEs (OR = 1.343, p = 0.040).

Conclusion

RAGE gene polymorphism has a significant effect on AGEs level and PON1 activity in diabetic subjects compared to healthy individuals. Diabetic patients with a CC genotype of − 429T/C are prone to develop MVC, more so if AGEs levels are high and PON1 activity is low.  相似文献   
59.
The aim of this study was to investigate the heart rate (HR) responses, the rate of perceived exertion (RPE), and the feeling during physical education schooling while performing traditional games activities compared to intermittent exercise. Nineteen pre-pubertal children randomly performed on different days two types of lessons (intermittent running mode vs. traditional Tunisian “Raqassa” game) lasting 12-min each. HR was continuously recorded during both lessons, while ratings of perceived exertion and Feeling values were recorded after the sessions. The mean HR value during the traditional game was significantly higher than during intermittent exercise (p<0.05). Conversely, the perceived exertion score was significantly higher after intermittent exercise than the traditional exercise game (p<0.05), showing that the higher cardiovascular strain of the game was perceived as “lighter” than the run. Simultaneously, the children''s Feeling was significantly higher after the traditional game than intermittent exercise (p<0.001), showing a higher satisfaction from playing with respect to running. Exercise based on the “Raqassa” traditional game could be used in pre-pubertal children as an alternative or as an additional method for suitable cardiovascular stimulation during physical education lessons with lower perceived exertion and better feeling compared to intermittent running.  相似文献   
60.
The objective of this study was to determine the effects of a 10-week dynamic back extension training programme and its effects on back muscle strength, back muscle endurance and spinal range of motion (ROM) for healthy young females. Seventy-three young females (age: 19.32±1.80 years, height: 158.89±4.71 cm, body weight: 55.67±6.30 kg) volunteered for the study. Prior to the training period, all participants completed anthropometric measurements, back muscle strength and endurance test, lateral bending and spinal ROM measurements. After measurements, the participants were divided into two groups. The exercise group (N:35) performed the dynamic back extension exercise 3 days per week for 10 weeks. The control group (N:38) did not participate in any type of exercise. The mixed design ANOVA (group x time) was used to determine the difference in pre- and post-training values. The present findings show that there were significant differences between pre-training and post-training values for back muscle strength and spinal ROM in the exercise group. Following the dynamic strength training programme, back muscle strength and spine ROM values except flexion of the lumbar 5-sacrum 1 (L5-S1) segment of the exercise group showed a significant increase when compared with the pre test values. The control group did not show any significant changes when compared with the pre-training values. The results demonstrate that the 10-week dynamic strength training programme was effective for spinal extension ROM and back muscle strength, but there was no change in back muscle endurance. In this context, this programme could potentially be used to prevent the decrease of spinal ROM as well as provide an increase in the fitness parameters of healthy individuals.  相似文献   
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