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41.
In this paper a population based evolutionary optimization methodology called Opposition based Harmony Search Algorithm (OHS) is applied for the optimization of system coefficients of adaptive infinite impulse response (IIR) system identification problem. The original Harmony Search (HS) algorithm is chosen as the parent one and opposition based approach is applied to it with an intention to exhibit accelerated near global convergence profile. During the initialization, for choosing the randomly generated population/solution opposite solutions are also considered and the fitter one is selected as apriori guess for having faster convergence profile. Each solution in Harmony Memory (HM) is generated on the basis of memory consideration rule, a pitch adjustment rule and a re-initialization process which gives the optimum result corresponding to the least error fitness in multidimensional search space. Incorporation of different control parameters in basic HS algorithm results in balancing of exploration and exploitation of search space. The proposed OHS based system identification approach has alleviated from inherent drawbacks of premature convergence and stagnation, unlike Genetic Algorithm (GA), Particle Swarm Optimization (PSO) and Differential Evolution (DE). The simulation results obtained for some well known benchmark examples justify the efficacy of the proposed OHS based system identification approach over GA, PSO and DE in terms of convergence speed, identifying the system plant coefficients and mean square error (MSE) fitness values produced for both same order and reduced order models of adaptive IIR filters.  相似文献   
42.
Apoptosis plays an important role in cellular homeostasis. In this study we have investigated whether apoptosis is a contributory factor to alcohol induced liver damage. Long term ethanol (1.6 g/kg body weight/day) exposure augmented liver apoptosis as reflected by high frequency of positive TUNEL staining nuclei and by an increased activity of caspase-3 and -8. Our study provides evidence that long-term ethanol consumption triggers apoptotic process in the liver.  相似文献   
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An imbalance in the systemic redox status leading to oxidative stress has been an important factor in development of senile cataracts, which is reflected by an increase in serum TBARS and a decrease in plasma SOD activity. Zinc has been an important cofactor required for structural stability of SOD. In the present study the role of serum zinc level and plasma SOD activity was analyzed in senile cataract patients showing significant oxidative stress. Serum TBARS, plasma SOD and serum zinc level was measured in thirty randomly selected senile cataract patients against properly matched controls. Although, the analysis of means showed a significant increase in serum TBARS and decrease in plasma SOD and serum zinc level in cases, but plasma SOD was found to be just significantly correlated (p=0.05) with the serum zinc only in the cases. The results of partial correlation studies and multiple regression analysis, also, showed only a significant correlation and predictable dependence between serum TBARS and plasma SOD, excluding any role of serum zinc level. The present study concludes that it is chiefly the plasma SOD activity, but not the serum zinc level, that determines the proneness of the patients for development of senile cataract.  相似文献   
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Serum and amniotic fluid mucoprotein concentrations were estimated in normal and toxaemic pregnant women. The levels were found to be higher in preeclampsia and eclampsia than the normal controls. Comparatively higher concentrations were observed in amniotic fluid than serum. Data suggest that the estimation of serum and amniotic fluid mucoproteins may be useful in assessing the severity of toxaemia of pregnancy and fetal well being.  相似文献   
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Alcohol appears to affect brain function, primarily by interfering with the action of gamma-aminobutyric acid (GABA) and other neurotransmitters. As alcohol is mainly metabolized in the liver, therefore we undertook this pilot study to monitor the patterns of changes in plasma amino-acid concentrations due to alcoholic and nonalcohol fatty liver disease and their relation with plasma GABA level. Plasma amino-acid concentrations were measured in 25 alcoholic liver disease (ALD) patients, 18 non-alcoholic fatty liver disease (NAFLD) patients, and 24 age and sex matched control subjects by HPLC. GABA concentration was elevated, while isoleucine and leucine levels reduced significantly in ALD patients compared to the control subjects. Methionine and phenylalanine levels elevated and valine content reduced significantly in ALD patients compared to other two groups, and GABA level was significantly correlated with methionine and phenylalanine. Plasma concentration of lysine was significantly reduced in both groups of liver disease patients compared to the control group, but was not correlated with GABA level. Glycine and tyrosine levels reduced significantly in NAFLD patients compared to other two groups and were significantly correlated with GABA. Interestingly, though amino acids such as alanine, histidine, proline and serine were not affected by liver diseases, but were significantly correlated with GABA level. This pilot study indicated that alcoholic liver disease presented a more deranged plasma amino acid pattern than nonalcoholic, and the amino acid imbalances. More studies are necessary to identify the role of any particular amino acid on brain function and on neurotransmitter(s).  相似文献   
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We report an unusual presentation of primary biliary cirrhosis. We present the case of a 31-year-old Indian woman who presented to the hospital with non specific complaints of gastritis, reduced appetite and marked weight loss and no complaints of pruritus. Serum liver enzymes were elevated. Cytoplasmic pattern of antinuclear antibodies was found on immunofluorescence microscopy accompanied by positive anti smooth muscle antibody. Endoscopy revealed esophageal varices. Following a liver biopsy, the diagnosis of primary biliary cirrhosis was made. It is important to consider the diagnosis of hepatic cirrhosis when patient presents with gastritis, reduced appetite and marked weight loss in both the presence and absence of ascites.  相似文献   
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