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141.
The supply of oxygen is limited in certain intra abdominal conditions due to direct vascular invasion or inflammatory process, resulting in high lactate levels. Aim of this study was to find the predictive value of lactate levels in the peritoneal fluid (PF) and blood of patients with acute abdomen. The study comprised of fifty patients with acute abdominal conditions, admitted in emergency ward of tertiary care hospital, thirty patients were with surgical abdomen (group I) and twenty patients with non surgical abdomen (group II). Lactate was estimated in PF and blood on Blood Gas Analyzer (NOVA, M-7). The mean lactate levels in PF were significantly higher in group I as compared to group II (14.65 ± 1.195 vs. 5.92 ± 0.97 mmol/L, p < 0.001). There was no significant difference in blood lactate levels in both the groups. When PF and blood lactate levels were compared within groups, we found that PF levels were significantly higher than blood in group I (14.65 ± 1.195 vs. 3.85 ± 0.54 mmol/L, p < 0.001) but not in group II (5.92 ± 0.97 vs. 4.36 ± 0.95 mmol/L). Diagnostic value was obtained using ROC curve. Cut off values obtained for PF lactate, difference and ratio of PF and blood lactate (≥6.4 mmol/L, ≥3.3 and ≥2.1 respectively) are at very high degree of sensitivity and specificity. So it can be useful marker of surgical emergency in patients with acute intra abdominal pathology, especially in clinically ill patients or in whom physical examination is not yielding because of neurologic disorders or unresponsiveness.  相似文献   
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143.
This article has two interrelated purposes. The first is to explain how various forms of bias, if introduced during any stage of a meta-analysis, can provide the consumer with a misimpression of the state of a research literature. Five of the most important bias-producing aspects of a meta-analysis are presented and discussed. Second, armed with this information, we examine 15 meta-analyses of the literatures of distance education (DE), online learning (OL), and blended learning (BL), conducted from 2000 to 2014, with the intention of assessing potential sources of bias in each. All of these meta-analyses address the question: “How do students taking courses through DE, OL, and BL compare to students engaged in pure classroom instruction in terms of learning achievement outcomes?” We argue that questions asked by primary researchers must change to reflect issues that will drive improvements in designing and implementing DE, OL, and BL courses.  相似文献   
144.
One’s self-concept and value perceptions can significantly influence one’s behaviours and beliefs. Australian teachers from urban and rural areas of the state of New South Wales were asked to respond to survey items on two predictors (teacher self-concept, valuing of learning) and three outcomes. Confirmatory factor analysis established the five latent factors. Structural equation modelling found significant paths from teacher self-concept to both student-centred and teacher-centred approaches but not beliefs about student ability. The positive path from valuing of learning to student-centred teaching was statistically significant but the path to teacher-centred teaching was not. The significant path from valuing of learning to beliefs about student ability was negative indicating that teachers who value student learning were less likely to believe in ability constraints. Therefore, teacher preparation programmes should enhance self-concept simultaneously with teaching skills and values and facilitate an advocacy for students’ learning.  相似文献   
145.
In the present study, we investigated the relationship between an important 27 bp repeat polymorphism in intron 4 of eNOS and numbers of circulating EPCs in presence of cardiovascular disease (CVD) risk factors in a group of healthy human volunteers. The study comprised of 45 healthy subjects (30–50 years). These subjects had various degrees of CVD risk but no history of CVD. The repeat polymorphism of eNOS was detected by polymerase chain reaction and EPC levels were analyzed by flow cytometry. We observed a good association between the intronic 4 mutant a/b genotype and the combined Framingham risk factor score in our subjects (χ2 = 3.2, P = 0.07). EPC numbers in subjects with mutant eNOS a/b genotype were also less than those observed in subjects with normal eNOS b/b genotype (P = 0.06). Interestingly, subjects with eNOS a/b genotype showed a significant inverse correlation between framingham risk score and EPC numbers (R = ?0.57, P < 0.05). The study suggests that the presence of CVD risk factors in subjects with eNOS intron 4 polymorphism results in reduced number of circulating EPCs, which may significantly predispose them to CVD and aberrant endothelial repair.  相似文献   
146.
The present study was undertaken to study the impact of surgical menopause on oxidant and antioxidant status in relation to estrogen levels after 3 months of surgery. Total 130 women who had undergone total hysterectomy (TH) with or without bilateral salpingo-oophorectomy (BSO) were included in this study. The oxidant status was assessed by measuring plasma levels of malondialdehyde and antioxidant status was assessed by measuring superoxide dismutase, catalase, glutathione, glutathione peroxidase, estrogen, and Vitamin A, E and C levels. The malondialdehyde level was significantly increased (p < 0.05) in all women who underwent TH with or without BSO. Significant increased levels of superoxide dismutase were observed in women who underwent TH with BSO. The blood glutathione levels were significantly decreased in women after TH only but significantly increased in women who had undergone TH with BSO. The levels of estrogen, vitamin E and vitamin C were significantly decreased in women who underwent TH with BSO. The catalase, GPx and vitamin A did not differ significantly in all groups. The result suggests that surgical menopause is associated with oxidative stress which reiterates the fact that ovaries retain some function even after menopause.  相似文献   
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