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71.
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73.
N.N. Singh M.G. Ahrens 《International Journal of Disability, Development & Education》1978,25(1):53-63
Incidental learning of film content was investigated in institutionalized retarded children. In the first of two studies, 40 retardates at six IQ levels, three MA levels, and five CA levels were tested. In the second study, 21 Down's Syndrome, organic, and familial retardates were tested. The stimuli consisted of an 8‐minute film which was shown individually. All subjects were questioned on twenty incidental aspects of the film. In Experiment 1, a curvilinear relationship was found between incidental learning and IQ. Incidental learning improved with MA. A retest, taken 120 hours later, revealed a 10.9 percent loss of incidental learning. Higher IQ children showed the greatest loss. Experiment 2 reported no difference in incidental learning as a function of etiology of retardation. A retest showed a short term memory deficit in organic retardates and a significant loss of incidental learning in Down's Syndrome and familial retardates. Implications of these results were discussed in terms of structured teaching techniques. 相似文献
74.
H. R. Mali S. A. Siddiqui Madhur Garg R. K. Singh M. L. B. Bhatt 《Indian journal of clinical biochemistry : IJCB》1998,13(1):36-40
Present study repots changes in serum copper levels (SCL) in various neoplastic diseases undergoing radiotherapy. We estimated
SCLs in 140 individuals comprising of 90 previously untreated patients with various malignancies and 50 healthy controls.
Patients received radiation in doses of 40–70 Gy in 4–7 weeks. SCLs were again estimated in patients following irradiation.
The mean SCL was significantly higher (P<0.001) in cancer patients as compared to healthy controls. It declined significantly
(P<0.001) following irradiation. However, it remained significantly higher as compared to healthy controls (P<0.01). Highest
fall in SCL was seen in complete clinical responders and least in non-responders to radiation treatment. Serial estimation
of SCLs may be useful in the treatment monitoring of the neoplasms undergoing radiation treatment. 相似文献
75.
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
76.
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
77.
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
78.
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
79.
80.
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