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The present study was undertaken to explore the relationship of plasma homocysteine with other biochemical parameters in ischemic heart disease. Plasma levels of total homocysteine was measured by HPLC—fluorescence detection with internal standard in 60 ischemic heart disease patients and were compared with 30 age matched normal healthy controls. The significant increase of plasma homocysteine was observed in both myocardial infarction and chronic stable ischemic heart disease patients when compared with the controls. The hyperhomocysteinemia appears be to due to increased body demand of vitamins such as folic acid, vitamin B12, B6, B2 either alone or in combination to regulate normal homocysteine metabolism.  相似文献   
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Non-alcoholic fatty liver disease shares many features of metabolic syndrome and its presence could signify a substantial cardiovascular risk above and beyond that conferred by individual risk factors. This study is an attempt to investigate the association of non-alcoholic fatty liver disease with carotid intima-media thickness and plaque as surrogate measures of increased cardiovascular risk. The study was conducted on 645 non diabetic, non alcoholic subjects in the age range of 20–60 years. Metabolic syndrome was assessed by using ATP III and ADA (2005) criteria. Anthropometric factors—waist circumference and blood pressure were measured. Fasting serum samples were analyzed for glucose, triglyceride, cholesterol and its fractions, insulin, alanine and aspartate transaminases, gamma glutamyl transferase and free fatty acids. Insulin resistance and secretion were calculated by homeostasis model and insulin sensitivity by QUICKI index. Liver ultrasonographic scanning was used for assessing fatty liver. Carotid atherosclerosis was assessed by B-mode ultrasonography of common carotid artery and internal carotid artery. The prevalence of non-alcoholic fatty liver disease was 15.6 % in non alcoholic population and 68.5 % of non-alcoholic fatty liver disease had metabolic syndrome, which was associated with hyperinsulinemia, insulin resistance, insulin insensitivity along with elevated levels of waist circumference, blood pressure, triglyceride, FFA and decreased HDL cholesterol. NAFLD patients had markedly greater carotid intima media thickness than non NAFLD subjects with MCIMT of 591.6 ± 108 and 489.5 ± 132.4 μm (P < 0.001) and plaque prevalence of 19.2 and 2.2 %, respectively, thus the carotid intima media thickness is associated with NAFLD.  相似文献   
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Impact of Chronic Lead Exposure on Selected Biological Markers   总被引:1,自引:0,他引:1  
Lead poisoning remains a major problem in India due to the lack of awareness of its ill effects among the clinical community. Blood lead, δ-aminolevulinic acid dehydratase (δ-ALAD) and zinc protoporphyrin (ZPP) concentrations are widely used as biomarkers for lead toxicity The present study was designed to determine the impact of chronic lead exposure on selected biological markers. A total of 250 subjects, of both sexes, ranging in age from 20 to 70 years, were recruited. On the basis of BLLs, the subjects were categorized into four groups: Group A (BLL: 0–10 μg/dl), Group B (BLL: 10–20 μg/dl). Group C (BLL: 20–30 μg/dl) and Group D (BLL: 30–40 μg/dl) having BLLs of 3.60 ± 2.71 μg/dl, 15.21 ± 2.65 μg/dl, 26.82 ± 2.53 μg/dl and 36.38 ± 2.83 μg/dl, respectively. Significant changes in biological markers due to elevated BLLs were noted. The relation of BLL and biological markers to demographic characteristics such as sex, habits, diet and substances abuse (smoking effect) were also studied in the present investigation. Males, urban population, non-vegetarians, and smokers had higher blood lead levels. δ-ALAD activity was found to be significantly lower with increased BLL (P < 0.001), while the ZPP level was significantly higher with increased BLL (P < 0.001). Further, BLL showed a negative correlation with δ-ALAD (r = −0.425, P < 0.001, N = 250) and a positive correlations with ZPP (r = 0.669, P < 0.001, N = 250). Chronic lead exposure affects the prooxidant-antioxidant equilibrium leading to cellular oxidative stress.  相似文献   
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The new Advanced Placement (AP) Computer Science (CS) Principles course increases the need for quality CS teachers and thus the need for professional development (PD). This article presents the results of a 2-year study investigating how teachers teaching the AP CS Principles course for the first time used online PD material. Our results showed that the teaching and computing background of teachers had a significant impact on the teachers' need for and use of online PD material. More specifically, novice CS teachers needed and used PD for developing their pedagogical content knowledge (PCK). Non-CS teachers needed and used PD materials emphasizing content knowledge. Experienced CS teachers believed they had little need for PD even though they were teaching a new course. Our study makes three recommendations for designing effective online PD for CS teachers: match PD to teachers' background, align PD with the course curriculum, and use effective motivational design to enhance teacher engagement. (Keywords: computer science education, online professional development, K–12, AP computer science principles course)  相似文献   
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We present the mathematical model and an artificial neural network method for calculating the buckling load of a beam column with different end conditions. A trial solution of the beam column equation is written as a sum of two parts, in which first part satisfies the boundary conditions and the second part represents the feed forward neural network containing adjustable parameters, weights and biases. We prepared the Error function by using the beam column equation and its boundary conditions, which is used in the back propagation method with deflection term to update the network parameters. It is found that the artificial neural network method is capable for calculating deflection of a beam column as a part of the training process. To ascertain the soundness, efficiency and accuracy of the proposed method the results are compared to the Euler critical load.  相似文献   
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