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51.
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Biman Nath 《Resonance》2008,13(8):772-774
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53.
Meta-analysis is the synthesis of findings from research projects, which enables an estimate of the average or pooled effect across various studies. This study presents findings from the intention to treat analysis for a series of educational evaluations in England using a two-stage meta-analysis with standardised outcome data and individual participant data meta-analyses. The research estimates the overall impact of educational trials on pupils eligible for Free School Meals (FSM) and the attainment gap in literacy and mathematics performance between FSM and non-FSM pupils based on analysis of 88 trials and data from over half a million pupils. For the meta-analyses, frequentist and Bayesian multilevel models were used to estimate the individual and pooled effect size across categories of explanatory variables such as age groups (key stages in England) and aspects of the type of interventions (one-to-one, small group, whole class). Results indicated that the overall impact of interventions on the literacy outcomes of FSM pupils was positive, with a pooled effect size of 0.06 (0.03, 0.08). However, for mathematics, no overall effect on FSM pupils was observed. Analysis of the attainment gap indicated that literacy outcomes for FSM pupils were improved by interventions marginally more than for non-FSM pupils (pooled attainment gap 0.01 (−0.01, 0.04)). The risk of bias assessment showed that estimates were consistent across different methodological approaches. Overall, evidence from this study can be used to identify, test and scale educational interventions in schools to improve educational outcomes for disadvantaged pupils.  相似文献   
54.
Given the significant negative impacts of peer victimization on youth development, studies have sought to understand what buffers against these consequences. To that end, the present study examined whether teacher attachment and perceptions of school safety moderated the associations between different forms of victimization and school absences over the course of an academic year among a sample of 272 high school students. Findings indicated that teacher attachment moderated the associations between relational and cyber victimization and absences, while perceived school safety moderated associations between relational victimization and absences. However, findings pertaining to cyber victimization were not as anticipated. Implications for prevention and intervention efforts in high schools are discussed.  相似文献   
55.
Serum antioxidant status and peroxidative stress was estimated in 30 pregnant women, their newborn infants and 25 non-pregnant women. Serum Ascorbic acid, α-tocopherol, retinol & β-carotene levels were found to be significantly reduced and peroxidative stress was significantly higher in mothers as compared to matched non-pregnant women. Newborn had significantly higher levels of ascorbic acid as compared to their mother but had significantly lower levels of lipid soluble vitamins. The peroxidative stress in newborn was found to be significantly less as compared to their mothers. A positive correlation of ascorbic acid and α-tocopherol levels between mother and newborn reflects that their status in mother does influence the newborn status.  相似文献   
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Normal and alloxan induced diabetic guinea pigs were kept on whole seed diet of green gram for 4 weeks. Serum total lipids were found to be significantly decreased in both normal and diabetic guinea pigs (P <0.001)—Both free and esterified fractions of cholesterol were found to be lowered significantly in diabetic animals (P<0.05; <0.01, respectively), whereas only esterified fraction was reduced significantly in case of normals (P<0.05). Significant lowering of triglyceride levels (P<0.01) was also noticed in both normal as well as diabetic guinea pigs while phospholipids remained almost unaffected. Green gram feeding decreased the total cholesterol / phospholipid ratio from 0.630 to 0.625 in normal and from 1.039 to 0.850 in diabetic guinea pigs indicating its antiatherogenic nature.  相似文献   
58.
The high mobility group (HMG) proteins I and Y are well characterised non-histone chromosomal proteins which bind to A-T rich regions of DNA and regulate gene expression and/or DNA replication. A correlation has been demonstrated between the increased expression of HMG-Y proteins and malignancy. However, it is not known whether the expression of HMGs particularly, the Y group, is a function of proliferation rate. In the present study, we have used normal tissues of calf testes, thymus and liver. The results show distinctly high expression of HMG-Y proteins in testes than in thymus and the expression was practically undetectable in liver. The results suggest that even in normal tissues there is a direct correlation between the proliferation rate and the expression of the HMG-Y proteins, which can partly explain its increased expression in cancer.  相似文献   
59.
348 patients of chronic obstructive pulmonary diseases (COPD) were studied for their acid base profile using ABL-3 blood gas analyser (Radiometer, copenhagan). 185 patients (53.1%) had simple disorders (respiratory acidosis—53%, respiratory alkalosis—25.4%, metabolic acidosis—11.3%, metabolic alkalosis—10.2%). Mixed disorders were present in 131 patients (34.9%) (respiratory acidosis and metabolic acidosis—75.2%, respiratory acidosis and metabolic acidosis—14%, metabolic acidosis and metabolic alkalosis—5.7%, metabolic alkalosis and respiratory alkalosis—4.9%). Hypoxemia without other acid base abnormalities was observed in early patients of GOPD (42 patients—12%). Chronic respiratory acidosis was the most common finding in advanced cases of COPD (98%). An almost equal number of such patients had a mixed disorder of respiratory acidosis with metabolic alkalosis (91%). Salt restriction, prolonged use of steriods and hypokalemia were often related to metabolic alkalosis in such patients.  相似文献   
60.
The present, study was conducted to determine the level of malondialdehyde (MDA) as an index of free radial induced lipid peroxidation and antioxidant vitamins-vitamins A, vitamin C and vitamin E in 75 confirmed cases of urolithiasis. Significantly high level of MDA (p<0.001) with significantly low levels of vitamin E (p<0.001) and vitamin A (p<0.001) with no significant decrease in vitamin C (p>0.05) were observed in the plasma of urolithiasis cases as compared to normal controls. In conclusion, it appears that a role of lipid peroxidation and oxidative function exists in the pathogenesis of urolithiasis. But, the exact mechanism how this occurs remains to be elucidated.  相似文献   
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