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71.
A. Supriya Simon D. Dinesh Roy V. Jayapal T. Vijayakumar 《Indian journal of clinical biochemistry : IJCB》2010,25(2):164-168
Cardiometabolic syndrome is one of the major public health issues of this century which describes a cluster of clinical characteristics.
Seventy two patients with coronary artery disease (CAD) and cardiometabolic syndrome and forty healthy age and sex matched
normal controls were selected for this study. Detailed clinical epidemiological and anthropometric characteristics were noted.
Lipid profile and Cytokinesis-block micronuclei (CBMN) assay using cytochalasin B were carried out in all the subjects. Serum
total cholesterol, triglyceride and LDL-cholesterol was significantly higher and HDL cholesterol was significantly lower in
patients compared to their normal counter-parts (P<0.05). CBMN frequency of the patients was significantly higher at all ages
compared to their normal counter parts (P<0.05). Various risk factors like diabetes, hypertension, dyslipidemia, abdominal
obesity, smoking and alcoholism were found influenced the CBMN frequency; but the changes were not significant. From this
study it can be concluded that DNA damage was found to be higher in patients with cardiometabolic syndrome which may be attributed
to the generation of free radicals associated with alcohol consumption, tobacco use, dyslipidemia and glucose intolerance
and the accumulation of free radicals with increase in age. 相似文献
72.
Singh PP Chandra A Mahdi F Roy A Sharma P 《Indian journal of clinical biochemistry : IJCB》2010,25(3):225-243
The antioxidants are essential molecules in human system but are not miracle molecules. They are neither performance enhancers
nor can prevent or cure diseases when taken in excess. Their supplemental value is debateable. In fact, many high quality
clinical trials on antioxidant supplement have shown no effect or adverse outcomes ranging from morbidity to all cause mortality.
Several Chochrane Meta-analysis and Markov Model techniques, which are presently best available statistical models to derive
conclusive answers for comparing large number of trials, support these claims. Nevertheless none of these statistical techniques
are flawless. Hence, more efforts are needed to develop perfect statistical model to analyze the pooled data and further double
blind, placebo controlled interventional clinical trials, which are gold standard, should be implicitly conducted to get explicit
answers. Superoxide dismutase (SOD), glutathione peroxidase and catalase are termed as primary antioxidants as these scavenge
superoxide anion and hydrogen peroxide. All these three enzymes are inducible enzymes, thereby inherently meaning that body
increases or decreases their activity as per requirement. Hence there is no need to attempt to manipulate their activity nor
have such efforts been clinically useful. SOD administration has been tried in some conditions especially in cancer and myocardial
infarction but has largely failed, probably because SOD is a large molecule and can not cross cell membrane. The dietary antioxidants,
including nutrient antioxidants are chain breaking antioxidants and in tandem with enzyme antioxidants temper the reactive
oxygen species (ROS) and reactive nitrogen species (RNS) within physiological limits. Since body is able to regulate its own
requirements of enzyme antioxidants, the diet must provide adequate quantity of non-enzymic antioxidants to meet the normal
requirements and provide protection in exigent condition. So far, there is no evidence that human tissues ever experience
the torrent of reactive species and that in chronic conditions with mildly enhanced generation of reactive species, the body
can meet them squarely if antioxidants defense system in tissues is biochemically optimized. We are not yet certain about
optimal levels of antioxidants in tissues. Two ways have been used to assess them: first by dietary intake and second by measuring
plasma levels. Lately determination of plasma/serum level of antioxidants is considered better index for diagnostic and prognostic
purposes. The recommended levels for vitamin A, E and C and beta carotene are 2.2–2.8 μmol/l; 27.5–30 μmol/l; 40–50 μmol/l
and 0.4–0.5 μmol/l, respectively. The requirement and recommended blood levels of other dietary antioxidants are not established.
The resolved issues are (1) essential to scavenge excess of radical species (2) participants in redox homeostasis (3) selective
antioxidants activity against radical species (4) there is no universal antioxidant and 5) therapeutic value in case of deficiency.
The overarching issues are (1) therapeutic value as adjuvant therapy in management of diseases (2) supplemental value in developing
population (3) selective interactivity of antioxidant in different tissues and on different substrates (4) quantitative contribution
in redox balance (5) mechanisms of adverse action on excess supplementation (6) advantages and disadvantages of prooxidant
behavior of antioxidants (7) behavior in cohorts with polymorphic differences (8) interaction and intervention in radiotherapy,
diabetes and diabetic complications and cardiovascular diseases (9) preventive behavior in neurological disorders (10) benefits
of non-nutrient dietary antioxidants (11) markers to assess optimized antioxidants status (12) assessment of benefits of supplementation
in alcoholics and heavy smokers. The unresolved and intriguing issues are (1) many compounds such as vitamin A and many others
possessing both antioxidant and non-antioxidant properties contribute to both the activities in vivo or exclusively only to
non-antioxidant activity and (2) since human tissues do not experience the surge of FR, whether there is any need to develop
stronger synthetic antioxidants. Theoretically such antioxidants may do more harm than good. 相似文献
73.
Ravinder Koul Roy B. Clariana Kalayanee Jitgarun Alisa Songsriwittaya 《Learning and individual differences》2009,19(4):506-512
This investigation considered how undergraduate students with different achievement goal orientation profiles view plagiarism. Thai student volunteers (N = 867) completed an achievement goal survey [Niemivirta, M. (1998). Individual differences in motivational and cognitive factors affecting self-regulated learning — A pattern-oriented approach. In P. Nenninger, R. S. Jäger, A. Frey, & M. Woznitza (Eds.), Advances in motivation (pp. 23–42). Landau, DE: Verlad Empirische Pädagogik] and a “Dimensions of Plagiarism” survey [Koul, R. (2007). Dimensions of Plagiarism. Downloaded April 8, 2008 from http://dimensions-of-plagiarism.wikispaces.com/]. Mixed analysis of variance of attitudes towards plagiarism with goal orientation and gender showed several significant findings: high performance oriented students were substantially stricter than low performance orientated students in evaluating all Dimensions of Plagiarism. Low mastery oriented students were stricter regarding the “motive” dimension of plagiarism while high mastery oriented students were stricter regarding the “source” dimension of plagiarism. Significant differences between females and males were observed across the six factors of the Dimensions of Plagiarism survey. These results are interpreted within the framework of social comparison theory in respect to competitive learning environments. 相似文献
74.
Educators have identified four categories of ‘productive pedagogies’ that are considered to lead to authentic student engagement and learning in the classroom. This study was designed to explore and extend these pedagogies in the context of learning in natural environments, in particular, through the programmes of Queensland environmental education centres. In‐depth interview and observation data were collected from students, classroom teachers and centre teachers who had participated in 12 environmental education programmes across Queensland, in order to identify the strategies that are most effective in facilitating learning in the natural environment. A fifth productive pedagogy category, ‘experience‐based learning’, is proposed. Experience‐based learning is particularly important in addressing students’ environmental attitudes and actions. The implications for the delivery of environmental education programmes both within and outside the classroom are discussed. 相似文献
75.
This paper explores the possible job creation effect of innovation activity. We analyze a unique panel dataset covering almost 20,000 patenting firms from Europe over the period 2003–2012. The main outcome from the proposed GMM-SYS estimations is the labor-friendly nature of innovation, which we measure in terms of forward-citation weighted patents. However, this positive impact of innovation is statistically significant only for firms in the high-tech manufacturing sectors, while not significant in low-tech manufacturing and services. 相似文献
76.
This study investigates the impact of an innovative conservation action campaign called Penguin Promises implemented at uShaka Sea World in Durban, South Africa. Communication tools included interpretive signage, exhibits with and without animals, presentations, and personal interactions, along with a specially designed postcard, on which visitors could write a promise (pledge) to make a change in their daily lives to become more environmentally responsible. Visitors who completed a card were contacted a year or more after their visit and asked about the outcomes of their promise. The results (N = 316) showed that 49.4% of respondents could give an example of something positive they had done for the environment, that they attributed to the campaign. Based on the study, recommendations are provided for the design of effective visitor conservation action campaigns. 相似文献
77.
在博物馆、科学中心和展览馆中利用数字技术学习 总被引:1,自引:1,他引:0
本文以博物馆和展览馆等利用数字化技术所提供的学习为综述对象,描述了博物馆学习的相关理论及发展;对在博物馆内、外利用数字化技术进行学习的趋势进行了预测;并针对未来发展趋势,对博物馆学习的设计者和开发者提供了相关建议。 相似文献
78.
79.
Abstract The study is concerned with the comparison of autonomic nervous system (ANS) activity between highly trained collegiate track and field athletes and untrained individuals. An ANS test battery consisting of six individual measures of autonomic activity was used: (a) sublingual temperature, (b) salivary output, (c) volar skin resistance, (d) palmar skin resistance, (e) diastolic blood pressure, and (f) heart period. One group of athletes, track runners, were found to have a mean autonomic balance score significantly higher (at the .02 level) than the norm group of college students. The autonomic scores of field event athletes, however, were not significantly different from the norm. An analysis of the type of ANS activity demonstrated by the runners showed a dominance by the parasympathetic as compared to a mixed pattern demonstrated by the normative sample. It was concluded that highly trained track runners demonstrated a significantly higher autonomic balance score than did normal college students, and that their resting autonomic pattern was predominantly parasympathetic. There was evidence to indicate that equality of performance in the running events in track, and possibly other athletic events, may be partially predictable from autonomic balance scores. 相似文献
80.
OBJECTIVES: To show that exposure to childhood maltreatment deteriorates, whereas exposure to adulthood military violence mobilizes social support; second, to show that associations between traumatic events and mental health problems are mediated through social support and, subsequently, adulthood military violence is associated with low level and childhood maltreatment with high level of mental health symptoms; third, to explore whether the moderating (protecting) effect of sufficient and satisfactory social support would differ among victims of childhood maltreatment and adulthood military violence. METHOD: The participants were a random-sample of Palestinian men and women (n=585) of 16-60 years of age. Exposure to military violence in adulthood was assessed by the Harvard Trauma Questionnaire (HTQ_I), and to childhood maltreatment by a 13-item questionnaire developed for the study. A Social Network Schedule was applied to assess the function, source, and satisfaction with social support, and the Revised SCL90-R Symptoms Checklist to assess mental health symptoms. RESULTS: Findings supported our hypothesis that exposure to childhood maltreatment was associated with low levels of social support, whereas exposure to adulthood military violence was associated with high levels of social support. Contrary to our second hypothesis, both childhood maltreatment and adulthood military violence were associated with high levels of mental health symptoms. Finally, high level and satisfactory social support moderated the association between exposure to military violence in adulthood and mental health symptoms, but not between childhood maltreatment and mental health symptoms. CONCLUSION: The findings emphasize that the nature of trauma, that is, whether familial or political, determines the availability of protective resources versus vulnerability, which should be considered when tailoring interventions to trauma victims. 相似文献