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31.
The present study was undertaken to analyze the antioxidant (both enzymic and nonenzymic) activities of leaves of Ocimum sanctum hydroalcoholic extract against cadmium induced damage in albino rats. Oral administration of cadmium as CdCl2 (6.0 mg/kg body weight) led to significant elevation of lipid peroxidation (LPO) levels and significantly decreased Superoxide Dismutase (SOD), Catalase (CAT), Glutathione Peroxidase (GPx), Reduced Glutathione (GSH) and Vitamin C (Ascorbate) levels. Administration of Ocimum sanctum extract (100 mg/kg body weight, po) and (200 mg/kg body weight, po) before and after cadmium intoxication showed a significant decrease in LPO levels and significant increase in SOD, CAT, GPx, GSH and Ascorbate levels. The results suggest that oral administration of Ocimum sanctum extract provides significant protection against cadmium induced toxicity in Wistar albino rats.  相似文献   
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If we adopt the definition that an earthquake is shaking of the earth due to natural causes, then we may argue that earthquakes have been occurring since the very beginning of the earth about 4.5 billion years ago.  相似文献   
35.
In the current study, we report perturbations in hepatic, renal and splenic heme synthesis at the level of the rate limiting enzyme, δ-amino levulinic acid synthase (ALA-S) on ethanol administration independently and in conjunction with iron-protoporphyrin (FePP) in male Wistar rats. Excessive ethanol administration (5 ml/kg bw) resulted in a significant induction of hepatic, splenic and renal ALA-S activity. Simultaneous administration of FePP (50 μmol/kg bw) reverted the observed induction response to a sharp decline. The features of the action of ethanol and FePP togetherin vivo, i.e. a substantial inhibition of ALA-S is suggestive of the beneficial effects of this formulation in acute attacks of porphyria.  相似文献   
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Dietary and lifestyle factors have been shown to have a profound effect on paraoxonase-1 (PON1) activity. Cigarette smoke has been shown to inhibit its mass and activity where as resveratrol has been shown to enhance it. We exposed hepatoma derived cell line (HepG2) to resveratrol and nicotine in varying doses and measured PON1 enzymatic activity and PON1 gene expression. In addition, total protein content of HepG2 cells was also measured. Resveratrol in a dose of 15 μmol/l or above significantly increased the PON1 enzyme activity (p > 0.001) where as nicotine in a dose of 1 μmol/l or higher significantly reduced it (p < 0.05). The resveratrol in this dose also enhanced the PON1 gene expression whereas nicotine decreased it as compared to controls. However, the protein conent of cells was not changed suggesting that they were not cytotoxic in the doses used. Till date the antioxidant vitamins have shown disappointing results against LDL oxidation and cardiovascular protection. However, the effect of resveratrol on PON1 gene expression and activity was significant, suggesting increase in PON1 activity and enhanced gene expression may be its alternative mechanism for offering protection against cardiovascular disease and may be an potential pharmacological agent which can be used for this.  相似文献   
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The Kármán vortex street is an exquisite flow pattern that can be seen in a variety of flow situations. In this article, we present some of the main features of the phenomenon starting from its interesting history, and also show why it is important in a number of engineering situations. Raghuraman N Govardhan is in the Mechanical Engineering Department at the Indian Institute of Science. He works in the areas of separated flow, fluid-structure interaction and micro-flows. O N Ramesh is at the Department of Aerospace Engineering, Indian Institute of Science, Bangalore. His research interests include transitional and turbulent flows, vortex dynamics and separated flows.  相似文献   
38.
2000 vials of lyophilized QC of two different levels (low and high) were donated by Roche Diagnostics GmbH, through the IFCC and received by CMCH in June 2001. A total of 240 la boratories were enrolled for this 6 month pilot study. In addition to the 12 analytes in the liquid QC programme, six additional analytes, LDH, triglyceride, urate, total bilirubin, phosphate and amylase were included. It was also possible to measure sodium and potassium by ion selective electrode (ISE) methods in the QC for the first time. The performance of the laboratories for the existing 12 analytes using liquid stabilized QC was compared to the performance using lyophilized QC. Using a statistical comparison of the methodwise mean variance index score (MVIS) values, five assays viz glucose, albumin, cholesterol, and SGOT and SGPT performance was the same in liquid QC and lyophilized QC. Three assays viz urea, calcium and creatinine were significantly better, and 4 assays total protein, sodium, potassium and ALP were significantly worse. However the overall VIS (OMVIS) for the laboratories was the same and the ranking pattern of this 6 month OMVIS was also unaltered. The lyophilized QC scheme highlighted a negative bias between flame and ISE methods for sodium and potassium, and a definite standardization problem in reporting LDH and amylase results, but triglyceride, urate and total bilirubin assays were performing well. It was concluded that the introduction of lyophilized QCs will not cause any deterioration of performance to participating laboratories. Stability of the material seems to be good and the laboratories are generally using a good reconstitution technique.  相似文献   
39.
This paper presents certain simple procedures for assessing the most common types of interference, due to haemolysis, icterus or lipaemic serum in 19 routine Clinical Chemistry tests and suggests steps to overcome the problem in some tests. A change in the measured concentration, to be analytically significant, had to exceed 2.8 X % coefficient of variation (cv) of the intra-assay analytical variation of each assay. Haemolysis caused interference in 10 of the 19 assays investigated. A haemolysate haemoglobin concentration of 0.29 g/dl, visible to the eye, caused an analytically significant increase in creatinine kinase MB subunit (CKMB), lactate dehydrogenase (LDH), total protein, triglyceride, uric acid and urea, and a significant decrease in alkaline phosphatase (ALP), and total bilirubin. A higher concentration of haemoglobin (0.68 g/ dl) caused an additional significant increase in CK, and a decrease in direct bilirubin. Addition of bilirubin caused interference in all the peroxidase linked reactions as well as in the creatinine assay. At a serum concentration of 5.2 mg/dl it caused a decrease in creatinine, glucose, triglyceride and uric acid. At a higher concentration (15.9 mg/dl) it also decreased cholesterol. Lipaemia interference affected the least number of assays. An added triglyceride of 537–561 mg/dl caused an increase in glucose, uric acid, and amylase. At a level of 1122 mg/dl it also increased CKMB, and at a value of 2244 mg/dl it increased total and direct bilirubin. At the highest levels of haemolysis and lipaemia, the serum glutamate oxaloacetate transaminase (GOT) and giutamate pyruvate transaminase (GPT) gave erratic results. Overall uric acid and CKMB were the analytes most susceptible to interference, while serum caicium and phosphate did not suffer from any. The interference depends on the exact assay conditions used and the susceptibility of each individual laboratory's tests should be determined by them. The reasons for the interferences described are discussed.  相似文献   
40.
Water extract of dry fruits ofTerminalia chebula (Hindi-Harda, Telugu-Karakkaya) at a dose of 200 mg/kg body weight improved the glucose tolerance as indicated by 44% of reduction in the peak blood glucose at 2nd hour in glucose tolerance test in diabetic (streptozotocin induced) rats. Treatment of diabetic rats with an initial fasting blood glucose of 253±9.4 mg/dl daily once with the water extract (200 mg/kg) for two weeks brought down the fasting blood glucose to 123±8.4 mg/dl which is only slightly above the normal value. These results indicate that water extract of Terminalia chebula improves glucose tolerance and brings down fasting blood glucose in diabetic rats.  相似文献   
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