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71.
Michael Singh 《Environmental Education Research》1998,4(3):341-354
This paper seeks to extend the range of critical literacy strategies that environmental educators might use in their engagement with curriculum policies. The paper focuses on a recent curriculum and professional development project from Australia as the context to illuminate and explicate particular critical reading strategies. Specifically, the paper introduces several critical reading strategies by applying them to an evaluation of the Global Education Project's review of global perspectives in curriculum policies from around Australia. 相似文献
72.
Tiwari AK Mahdi AA Zahra F Chandyan S Srivastava VK Negi MP 《Indian journal of clinical biochemistry : IJCB》2010,25(4):411-418
The present study was conducted to investigate the oxidant–antioxidant status in iron deficient pregnant anemic women. One
hundred thirty pregnant women with iron deficiency anemia (IDA) were divided into three groups, namely mild (50), moderate
(50) and severe (30) anemic along with pregnant healthy women as controls (50). The complete blood count, plasma lipid peroxidation
products, enzymatic and non-enzymatic antioxidants were measured according to respective protocols. The levels of complete
blood count, iron, ferritin along with antioxidant enzymes namely catalase, superoxide dismutase, glutathione peroxidase,
glutathione reductase and reduced glutathione were significantly reduced in all IDA groups. However, the level of oxidized
glutathione, lipid peroxides, protein carbonyls, conjugated dienes were found significantly increased in all anemic patients.
Antioxidant vitamins, namely C, E and A were also found significantly decreased in IDA patients. On the basis of our results,
it may be concluded that IDA tends to increase the pro-oxidant components, which may result in various complications including
peroxidation of vital body molecules resulting in increased risk for pregnant women as well as fetus. 相似文献
73.
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
74.
Anita Devi Ritu Singh Rajni Dawar Sanjay Tyagi 《Indian journal of clinical biochemistry : IJCB》2017,32(2):235-238
Association of cholesteryl ester transfer protein (CETP) Gene -629C/A Polymorphism with angiographically proven atherosclerosis CETP gene has been linked to CAD risk via its role in HDL and LDL metabolism. There is no agreement of whether CETP is atherogenic or not. Furthermore, various genotypes of CETP gene have been associated with CETP levels and thus with atherosclerosis risk. Our aim was to study the association of CETP -629C/A gene polymorphism with CETP and HDL levels and their association if any with atherosclerosis. Study population consisted of angiographically documented 50 cases with coronary artery atherosclerosis and 50 controls negative for atherosclerosis of coronary artery. Serum lipid profile was measured on SYNCHRON CX-9 using standard kits. Serum CETP levels were measured by ELISA method. CETP -629C/A gene polymorphism was studied using PCR–RFLP method. There was no significant difference in lipid profile of the two groups. However, serum CETP level was significantly higher (46.44 ± 21.75 ng/ml) in cases than controls (37.10 ± 21.92 ng/ml) with p value =0.035. The frequency of -629A allele was higher (0.85) in cases than that of controls (0.81). Homozygosity of A allele was more in subjects with atherosclerosis of coronary artery. We conclude that CETP is atherogenic and could be used as atherogenic risk predictor in angiographically proven atherosclerosis. Also A allele of -629C/A polymorphism is more prevalent in cases; indicating its effect on expression of CETP gene. 相似文献
75.
76.
Chandan Singh Dalawat 《Resonance》2009,14(12):1183-1205
The ancient unsolved problem of congruent numbers has been reduced to one of the major questions of contemporary arithmetic: the finiteness of the number of curves over Q which become isomorphic at every place to a given curve. We give an elementary introduction to congruent numbers and their conjectural characterisation, discuss local-to-global issues leading to the finiteness problem, and list a few results and conjectures in the arithmetic theory of elliptic curves. 相似文献
77.
Rajesh Kumar Kori Manish Kumar Singh Abhishek Kumar Jain Rajesh Singh Yadav 《Indian journal of clinical biochemistry : IJCB》2018,33(4):372-381
The problem of pesticides is not new and its exposure to human due to indiscriminate use is largely associated with the health related problems including neurotoxicological alterations. High levels of pesticide residues and their metabolites in the dietary constituents, food materials, maternal blood, cord blood, placenta breast milk have been reported and linked to alterations in birth weight, crown heel length, head circumference, mid-arm circumference and ponderal index of the neonates. Epidemiological studies have suggested that exposure of pesticide to human could be a significant risk factor for neurological disorders, including Parkinson’s disease, Alzheimer’s disease and multiple sclerosis. Cholinergic and non-cholinergic dysfunctions in pesticide exposed population, especially in children have also been frequently reported in recent years. Developmental neurotoxicity is another concern in the area where pregnant are more prone towards its exposure and which results in the abnormalities in the fetus. In view of the increasing risk of human health through pesticide exposure, the present review has been focused on the studies pertaining to pesticide induced neurochemical alterations and associated behavioral abnormalities in farm workers which could establish a possible link between the its exposure and associated health hazards. 相似文献
78.
Gaurav Chikara Pramod Kumar Sharma Pradeep Dwivedi Jaykaran Charan Sneha Ambwani Surjit Singh 《Indian journal of clinical biochemistry : IJCB》2018,33(2):121-131
Prevalence of diabetes mellitus, a chronic metabolic disease characterized by hyperglycemia, is growing worldwide. The majority of the cases belong to type 2 diabetes mellitus (T2DM). Globally, India ranks second in terms of diabetes prevalence among adults. Currently available classes of therapeutic agents are used alone or in combinations but seldom achieve treatment targets. Diverse pathophysiology and the need of therapeutic agents with more favourable pharmacokinetic-pharmacodynamics profile make newer drug discoveries in the field of T2DM essential. A large number of molecules, some with novel mechanisms, are in pipeline. The essence of this review is to track and discuss these potential agents, based on their developmental stages, especially those in phase 3 or phase 2. Unique molecules are being developed for existing drug classes like insulins, DPP-4 inhibitors, GLP-1 analogues; and under newer classes like dual/pan PPAR agonists, dual SGLT1/SGLT2 inhibitors, glimins, anti-inflammatory agents, glucokinase activators, G-protein coupled receptor agonists, hybrid peptide agonists, apical sodium-dependent bile acid transporter (ASBT) inhibitors, glucagon receptor antagonists etc. The heterogeneous clinical presentation and therapeutic outcomes in phenotypically similar patients is a clue to think beyond the standard treatment strategy. 相似文献
79.
Shibba Takkar Chhabra Shivani Mehta Sandeep Chhabra Manikant Singla Naved Aslam Bishav Mohan Gurpreet Singh Wander 《Indian journal of clinical biochemistry : IJCB》2018,33(2):235-238
Torsades de pointes with prolonged QTc interval is a form of ventricular tachycardia. Many predisposing factors have been identified and hypocalcemia is among the rare ones. Our case illustrates that though rare, hypocalcemia might manifest as torsades de pointes with prolongation of QTc interval. Early diagnosis and management of dyselectrolytemia can prevent these patients from catastrophic torsades de pointes. 相似文献
80.
Tracey Wai Man Tsang Michael Kohn Chin Moi Chow Maria Fiatarone Singh 《Journal of sports sciences》2013,31(12):1249-1267
Abstract The Chinese martial arts (Kung Fu) have existed for centuries and are generally accepted as being beneficial for health without much empirical data. The aim of this systematic review was to assess the health effects of “hard” Kung Fu styles by performing electronic and manual searches of the literature. The aspects of health and the Kung Fu style examined varied between most studies; in some cases, the martial art group consisted of practitioners of other martial art styles also. Of 2103 references identified, only nine papers were eligible and reviewed. All were observational studies, observing a range of health aspects possibly related to Kung Fu training or performance. Our findings suggest that there is no evidence that Kung Fu practice is associated with the prevention or treatment of any health condition. However, as a moderate- to high-intensity form of aerobic exercise, it may confer benefits similar to those attributed to other aerobic training modalities. However, this hypothesis remains to be tested in clinical trials. Physiological benefits (e.g., aerobic capacity and bone density) may be associated with long-term Kung Fu practice. Future research in this area should adopt experimental designs, clearly identifying eligibility criteria, testing and training protocols, and include health-related outcomes and documentation of adverse events, to advance knowledge in this field. 相似文献