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1.
Oxidative stress was assesed by estimating lipid peroxidation product (LPO) in the form of thiobarbituric acid reactive substances (TBARS), enzymatic antioxidants in the form of superoxide dismutase (SOD), catalase and nonenzymatic antioxidant vitamins e.g. vitamin C, β carotene and vitamin E in either serum or plasma or erythrocytes in 190 cases of age related cataract in the age group of 50–80 years. 190 cases were grouped into three morphological types namely, 73 cases of cortical, 77 cases of posterior subcapsular and 40 cases of nuclear cataract and values of LPO and antioxidants were compared with 78 cases of age matched healthy control groups. Plasma TBARS levels were cataract cases when compared with control groups. There were no significant differences in the erythrocyte levels of catalase and plasma levels of Vit E between cataract cases and control groups. No significant changes of parameters were seen among three different morphological types of age related cataract. The present study shows that the oxidative stress may play an important role in the age related cataract.  相似文献   
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Oral cancer has emerged as an alarming public health problem with increasing incidence and mortality rates all over the world. Therefore, the implementation of newer screening and early detection approaches are of utmost importance which could reduce the morbidity and mortality associated with this disease. Sensitive and specific biomarkers for oral cancer are likely to be most effective for screening, diagnosis, staging and follow-up for this dreaded malignancy. Unlike other deep cancers, oral cancer is located in oral cavity. Hence, the direct contact between saliva and oral cancer lesion makes the measurement of tumor markers in saliva an attractive alternative to serum and tissue testing. The DNA, RNA and protein molecules derived from the living cancer cells can be conveniently obtained from saliva. Thus, salivary biomarkers, a non-invasive alternative to serum and tissue-based biomarkers may be an effective modality for early diagnosis, prognostication and monitoring post therapy status. In the current post-genomic era, various technologies provide opportunities for high-throughput approaches to genomics and proteomics; which have been used to evaluate altered expressions of gene and protein targets in saliva of oral cancer patients. The emerging field of salivary biomarkers has great potentials to prove its clinical significance to combat oral cancer. Hence, we have reviewed importance of several salivary genomics and proteomics biomarkers for oral cancer.  相似文献   
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Harnessing sunlight for the production of electrical energy is an engrossing prospect. The crucial concept underlying the success of solar power stations is energy storage and its retrieval on demand which can be most effectively achieved with storage batteries. This article highlights the chemistry of existing and emerging battery technologies.  相似文献   
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A K Shukla 《Resonance》2001,6(11):49-62
Road transportation as an important requirement of modern society is presently faced with restrictions in mainly two respects, namely the ever tightening emission legislation as well as the availability of petroleum fuels, and as a consequence the fuel cost. But in any review of power sources for future road transport vehicles, the performance of the existing internal combustion engine is likely to be the yardstick against which other power sources will be compared. The power sources most likely to provide favourable comparison are those, which can display comparable range and speed, long and reliable life and manufactured at a cost comparable to petrol engine. A vehicle which fails in any of these requirements is unlikely to achieve anything but a niche market share. This article is an appraisal of a variety of proposed electrochemical systems, viz. rechargeable batteries, fuel cells and supercapacitors, for an electric car. It is surmised that a viable electric car could be powered with a fuel cell to provide power for cruising and climbing coupled in parallel with a supercapacitor/battery bank to deliver additional short-term burst-power during acceleration. A K Shukla is a Professor at the Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore. His current research interests are in materials electrochemistry with special emphasis on batteries, fuel cells and supercapacitors.  相似文献   
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The quality of evaluation of essay type answer books involving multiple evaluators for courses with large number of enrollments is likely to be affected due to heterogeneity in experience, expertise and maturity of evaluators. In this paper, we present a strategy to detect anomalies in evaluation of essay type answers by multiple evaluators based on the relationship between marks/grades awarded and symbolic markers, opinionated words recorded in answer books during evaluation. Our strategy is based on the results of our survey with evaluators, analysis of large number of essay type evaluated answer books and our own experiences regarding grievances of students regarding marks/grades. Results of both survey and analysis of evaluated answer books identified underline, tick and cross as frequently used markers compared to circle and question mark. Further, both opinionated words and symbolic markers identified through the survey are used by evaluators to express either positive or negative sentiments. They have differential usage pattern of these symbols as single evaluator and as one amongst multiple evaluators. Tick and cross have well define purposes and have strong correlation with marks awarded. However, the underline marker is being used for dual purpose of expressing both correctness and incorrectness of answers. Our strategy of inconsistency detection first identifies outliers based on the relationship between marks/grades awarded and number of symbols and/or opinionated words used in evaluation. Subsequently, marks and number of symbolic markers of outliers are compared with peer non-outlier answer books having same marks but different number of markers used. Such outlier answer books are termed as anomalous. We discovered 36 anomalies out of total 425 evaluated answer books. We have developed a prototype tool to facilitate online evaluation of answer book and to proactively alert evaluators of possible anomalies.  相似文献   
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An unexpected increase in erythrocyte osmotic resistance during viral hepatitis in two patients prompted study of effects of hepatitis (in Karad) on osmotic resistance. The test was performed by placing erythrocytes in saline solutions of decreasing osmolarity and osmotic fragility defined in terms of the saline concentration at which hemolysis begins. Study included 44 infected subjects (acute viral hepatitis non-A non-B). All forty four infected subjects showed abnormal results when compared to normal subjects. increased erythrocyte osmotic resistance i.e. hemolysis begins between 0.45% to 0.40% of NaCl and is completed between 0.25% to 0.20% NaCl, whereas in normal subjects. hemolysis begins between 0.50% to 0.45% NaCl and is completed between 0.35% to 0.30% NaCl. Osmotic resistance was observed with increase in total bilirubin (mean±SD) (4.6 ±3.6), direct bilirubin (3.0±2.5), SGOT (58.8±55.5) SGPT (114.2±150.3) activity. Physiologic shifts in erythrocyte osmotic resistance may be due to changes in membrane lipid ratio.  相似文献   
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The objectives of the present study were to ascertain the variations in the serum levels of malondialdehyde and total antioxidant status, in head and neck malignancies with different stages, with and without oral antioxidant supplementation, before and after radiotherapy, and to validate the protective effects of an antioxidant supplementation during radiotherapy. The pretreatment values of serum malondialdehyde were significantly raised, while that of serum total antioxidant status were significantly declined in all the stages of head and neck malignancies, when compared with the healthy controls values (P<0.001). A significant correlation was observed related to the studied parameters and different stages of the disease. The study suggests that an oral antioxidant supplementation during radiotherapy is an effective mode in reducing oxidative stress. Antioxidant supplementation during radiotherapy may serve as an adjuvant therapy in malignancies offering a protection to normal cells that may further reduce the risk of developing secondary cancers.  相似文献   
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Aqueous and alcoholic extracts of amalki (Emblica officinalis), spirulina and wheatgrass were prepared and analyzed for antioxidant vitamin content (vitamin C and E), total phenolic compounds. Antioxidant status, reducing power and effect on glutathione S-transferase (GST) activity were evaluated in vitro. Vitamin C content of crude amalaki powder was found to be 5.38 mg/g, while very less amount 0.22 mg/g was detected in wheat grass. Amalki was rich in vitamin E like activity, total phenolic content, reducing power and antioxidant activity. Total antioxidant activity of aqueous extract of amalki, spirulina and wheat grass at 1mg/ml concentration were 7.78, 1.33 and 0.278 mmol/l respectively. At similar concentrations the total antioxidant activity of alcoholic extract of amalaki, spirulina and wheat grass was 6.67, 1.73 and 0.380 mmol/l respectively. Amalki was also found to be rich source of phenolic compounds (241mg/g gallic acid equivalent). Alcoholic extract of wheat grass showed 50 % inhibition in FeCl2- ascorbic acid induced lipid peroxidation of rat liver homogenates in vitro. Both aqueous and alcoholic extracts of amalaki inhibited activity of rat liver glutathione S-transferase (GST) in vitro in dose dependant manner. Since GST acts as powerful drug metabolizing enzyme its inhibition by amalaki offers possibility of its use for lowering therapeutic dose of herbal preparations. The aqueous extracts of both amalki and spirulina also showed protection against t-BOOH induced cytotoxicity and production of ROS in cultured C6 glial cells.  相似文献   
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ObjectiveThe aims of this cross-sectional survey were to examine the prevalence, type and intensity of abuse in street children in Jaipur city, India.MethodBased on purposive random sampling, 200 street children, inclusive of equal number of boys and girls, were selected from the streets of Jaipur city, India, and administered an in-depth interview schedule which included five areas of abuse, namely, “general abuse,” “health abuse,” “verbal abuse,” “physical abuse,” and “psychological abuse.” Data was interpreted using percentages, t-test and correlations.ResultsStreet children reported experiences of abuse in all the five areas under study. Larger numbers of children (61.8%) scored in the “moderate” category of abuse while 36.6% children indicated abuse in “severe” and “very severe” categories on the intensity of abuse. Highest mean scores were obtained on the “verbal” and “psychological” area of abuse. Gender differences were significant in health and overall abuse, indicating boys to be significantly more abused than girls. There were significant positive correlations of abuse with increasing “age” and “income” of street children; and the occurrence of “multi-type” maltreatment and neglect in street children was clearly present.ConclusionDifferent forms of abuse are prevalent in street children in India. This area of study needs attention both by the researchers and the social workers.Practice implicationschildren who are identified in severe and very severe categories of abuse should be worked with in a follow up study with the help of governmental and nongovernmental agencies working in the field for child welfare.  相似文献   
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