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This study was conducted to find out the level of oxidative stress and effect of supplementation of vitamin C, D and Calcium on levels of SOD, serum and urinary fluoride in children residing in endemic fluorosis area. For this the fluoride belt of Jaipur district was selected. The parameters selected were Super oxide dismutase, serum fluoride and urinary fluoride. The study was conducted on one hundred children, selected from four areas (25 from each area) consuming water containing 1.2, 2.4, 5.6 and 13.6 mg/l of fluoride. Drinking water fluoride, serum and urinary fluoride were measured by Ion selective electrode method. Serum SOD by Xanthine oxidase method using kit of Ransod (kit cat. No. SD125). The post treatment values showed a significant reduction in serum fluoride and SOD. Urinary fluoride levels increased significantly in post treatment stage. The results revealed a normal SOD levels in all groups but an increasing trend was observed with increasing fluoride concentration. Treatment with Calcium, Vitamin D and Vitamin C showed a significant reduction in serum fluoride and SOD and increase in urinary fluoride. A high positive correlation between pretreatment and post treatment group was observed in serum fluoride, SOD and urinary fluoride (P < 0.05). The study indicated an increasing oxidative stress in cases of fluorosis with increasing drinking water fluoride concentration. Treatment with Calcium, Vitamin D and Vitamin C resulted a significant reduction in serum fluoride and SOD and increase in urinary fluoride.  相似文献   
988.
The present study examined whether the use of concept mapping is more effective in teaching expository material in comparison to a traditional, lecture only, approach. Its objective was threefold. First, to determine if multimedia concept mapping produces differential learning outcomes compared to digital text-based concept mapping. Secondly, to compare the above experimental approaches to traditional teaching and finally to demonstrate if there are significant differences in the level of satisfaction reported by children under the three instructional approaches used. Thirty fifth grade children participated from which three groups of poor readers were formed, matched on age, gender and reading ability. The two experimental groups were taught with the use of digital text-based and multimedia concept maps respectively and the control group was subjected to the traditional teaching method of expository material. Each group had three sessions of instruction on three different expository texts. The results indicated that concept mapping can be an effective means for teaching expository content. However, there were no differential learning outcomes when adding multimedia elements to concept maps. Moderate satisfaction was reported for all three approaches. The findings coincide with the body of literature emphasizing the importance of concept mapping in the learning and instruction of children with reading difficulties. The study’s results inform potential educators on the use of multimedia with poor readers in elementary school.  相似文献   
989.
The main purpose of this study was to investigate Taiwanese high school students’ multi-dimensional self-efficacy and its sources in the domain of science. Two instruments, Sources of Science Learning Self-Efficacy (SSLSE) and Science Learning Self-Efficacy (SLSE), were used. By means of correlation and regression analyses, the relationships between students’ science learning self-efficacy and the sources of their science learning self-efficacy were examined. The findings revealed that the four sources of the students’ self-efficacy were found to play significant roles in their science learning self-efficacy. By and large, Mastery Experience and Vicarious Experience were found to be the two salient influencing sources. Several gender differences were also revealed. For example, the female students regarded Social Persuasion as the most influential source in the “Science Communication” dimension, while the male students considered Vicarious Experience as the main efficacy source. Physiological and Affective States, in particular, was a crucial antecedent of the female students’ various SLSE dimensions, including “Conceptual Understanding,” “Higher-Order Cognitive Skills,” and “Science Communication.” In addition, the variations between male and female students’ responses to both instruments were also unraveled. The results suggest that, first, the male students perceived themselves as having more mastery experience, vicarious experience and social persuasion than their female counterparts. Meanwhile, the female students experienced more negative emotional arousal than the male students. Additionally, the male students were more self-efficacious than the females in the five SLSE dimensions of “Conceptual Understanding,” “Higher-Order Cognitive Skills,” “Practical Work,” “Everyday Application,” and “Science Communication.”  相似文献   
990.
Premature coronary artery disease (CAD) is common in India. We, therefore, studied oxidative stress, dyslipidemia, and high sensitivity-C reactive protein (hs-CRP) levels in young CAD patients. Present study consisted of male CAD patients below 40 years and age and sex matched healthy controls (n=30 each). Fasting blood samples were analyzed for serum lipid profile, malondialdehyde, antioxidant enzymes and hs-CRP levels. Dyslipidemia was observed in 90% of the young CAD patients, of which 72.2% showed increased serum triglycerides and decreased HDL-cholesterol. LDL-cholesterol levels were high in 77.8%. Serum malondialdehyde and hs-CRP levels were increased significantly (p<0.0001) as compared to controls. hs-CRP levels were in high risk range in all the young patients. However, glutathione peroxidase activity was reduced significantly (p<0.05). Our data suggests that elevated hs-CRP levels along with dyslipidemia and oxidative stress adds to the predictive value of premature CAD in young Indians.  相似文献   
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