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Reactive oxygen species (ROS) formed in various metabolic reactions cause unlimited damage by attacking and oxidizing the macromolecules. An arsenal of antioxidant substances neutralizes these ROS at various sites of their metabolic cascade, and if disequilibrium exists between the pro and antioxidant system, oxidative stress persists. The present study was undertaken in schizophrenia, to highlight the response and role of some endogenous antioxidants viz. reduced glutathione (GSH), bilirubin, total proteins, albumin and uric acid in scavenging the ROS. The effect of severity of disease, age factor, and substance abuse was also studied. In all, 50 schizophrenics and 50 age and sex-matched controls were enrolled in the present study. Fasting blood samples were drawn for estimating malondialdehyde (MDA), GSH, bilirubin, total proteins, albumin and uric acid in both the groups. The results were statistically analyzed by Z-test and correlated using correlation coefficient (r). The study shows reduction in MDA levels and decline in the level of endogenous antioxidants, but within the normal range. Chronic schizophrenics were at a higher risk of oxidative stress and age and substance abuse seems to worsen the situation.  相似文献   
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Variability in analytical performance of some analyte indicated the need of evaluation of quality plan of our laboratory. We tried to put the same degree of effort into our quality metrics as we put into the laboratory processes themselves. Application of six sigma methodologies improve the quality by focusing on the root causes of the problems in performance and analyzing by flowcharts, fishbone diagrams and other quality tools. Sigma metric was calculated for laboratory parameters for a period of 8 months during 2018–19. The analytes with poor sigma metric were free Thyroxine (FT3, FT4), Sodium, Calcium and Magnesium. Sigma metric of free Thyroxine (FT3, FT4), Sodium, Calcium and Magnesium were below 3. A road map for process improvement was designed with DMAIC (Define-Measure-Analyze-Improve-Control) model to solve the issue. Possible causes for low analytical performance of the particular analytes were depicted in Fishbone diagram. The Fishbone analysis identified the water quality issues with electrolyte analysis while high ambient temperature was culprit for poor assay performance of free Thyroxine. Sigma metric of the analytical performance was assessed once again after root cause analysis. Sigmametric showed marked improvement in control phase. Identification of problems led to reduction in non value added work leading to adequate resource utilization by addressing the priority issue. Therefore, DMAIC tool with Fish bone model analysis can be recommended as a well suited method for troubleshooting in poor performance of laboratory parameter.  相似文献   
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Exposure to arsenic has been associated with several health hazards. Worldwide the main reason for chronic human intoxication with arsenic is intake of contaminated drinking water. Air acetylene type of atomic absorption spectrophotometer in combination with hydride generator accessory was used to analyze arsenic level in 25 water samples collected from 25 booster pumping stations and 313 water samples collected from tap water supply of 62 areas of Delhi. Results were analyzed using SPSS and Barlett’s Chi Square Test. Mean arsenic level detected in water samples collected from booster pumping stations was 0.00976 ppm (Range 0.000–0.017 ppm, Standard Deviation 0.006 and Standard error of Mean 0.00118). Maximum arsenic level (0.017 ppm) was found in water samples of booster pumping stations of Mehrauli, Punjabi Bagh and Ramjas Road. Mean arsenic level detected in samples collected from tap water supply was 0.013 ppm (Range 0–0.0430 ppm, Standard Deviation 0.00911 and Standard error of Mean 0.000515). In water samples of 42 areas arsenic level detected was exceeding WHO/EPA permissible limit of 0.01 ppm (10 ppb). The mean arsenic level detected in water samples of booster pumping station was within WHO/EPA permissible limit while mean arsenic level detected in tap water samples was marginally higher. Mixing of ground water and contamination through broken or leaking channel could be the possible reason of higher arsenic level in tap water. Continuous monitoring of quality of drinking water is required particularly in view of water contamination caused by industrial waste and uncontrolled ground water extraction.  相似文献   
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Nineteen subjects of non-insulin dependent diabetes mellitus (NIDDM) between the age group of 30–60 yrs were studied to see the effect of specific yoga asanas on fasting and postprandial blood glucose (FBG, PPG), serum malondialdehyde (MDA) and glycosylated hemoglobin (HbA1) in addition to drug treatment and diet control. The duration of diabetes ranged from 1–10 years. Patients with renal, cardiac and proliferative retinal diseases were excluded from the study. The same patients served as their own control. Subjects were called in the morning to the cardio-respiratory laboratory and were given training by a yoga expert. Yoga asanas included Suryanamskar, Tadasan, TriKonasan, Padmasan, Pranayam, Paschimottanasan, Ardhmatsyendrasan, Pavanmukthasan, Sarpasan and Shavasan. The asanas were done every day for 40 days for 30–40 min. FBG, PPG, serum MDA and HbA1 were estimated before and after 40 days of yoga asanas regimen. Significant reduction was seen in FBG from 220 mg/dl to 162 mg/dl, PPG from 311 mg/dl to 255 mg/dl, MDA from 6 nmol/l to 3 nmol/l and HbA1, from 8.8% to 6.4%. Subjects felt better and were relieved of their stresses and had an improvement in their day to day performance. The decrease was statistically significant (p<0.0001 for FBG and PPG, p<0.001 for MDA and for HbA1).  相似文献   
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Protein fraction termed P2 was obtained from sonicates of Mycobacterium smegmatis, subjected to ammonium sulphate precipitation. P2 fraction was further fractionated into 4 fractions (PeakI-IV) by DEAE cellulose ion-exchange chromatography. ELISA was performed on the sera of 104 tuberculous cases and 62 controls, using P2 fractions Peak I as test antigens. Though the mean ELISA values in tuberculous cases were higher than the controls, no statistically significant difference was found between the two. Antigens P2, Peak I and IV were tested on Western blots with pooled sera from tuberculous cases as well as controls. P2 fraction, Peak-I and IV were separated on PAGE-SDS, electroblotted onto nitrocellulose Sheets and the blots were subjected to ELISA. Peak IV appeared as a single band (M.W. 55,000). P2 fraction exhibited some discriminatory bands on development of blots.  相似文献   
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