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941.
Seema Gupta Rajesh Pandey Ranjan Katyal H. K. Aggarwal R. P. Aggarwal S. K. Aggarwal 《Indian journal of clinical biochemistry : IJCB》2005,20(1):67-71
The present study was conducted to evaluate some of the components of antioxidant defense system and oxidative damage in 20
male patients of alcoholic liver disease (ALD). The results were compared with 20 healthy male smokers and 20 healthy male
non-smokers volunteers. Patients were subjected to detailed clinical examination and laboratory investigations. Blood samples
were collected for estimating reduced glutathione (GSH), total thiols (T-SH) malondialdehyde (MDA), transaminases (AST, ALT),
glutathione-S-transferease (GST) and gammaglutamyl transferase (GGT). Serum aspartate amino transferase (AST)/alanine amino
transferase (ALT) ratio was significantly (p<0.01) reduced in ALD patients as compared to the controls. However, the core
of utility of MDA and GST was found to be significantly (p<0.01) increased in ALD patients compared to controls. There was
a significant negative correlation of MDA with both GSH and TSH. Plasma GGT levels were significantly (p<0.01) increased in
alcoholics and the enzyme showed a significant positive correlation with MDA. These results give enough evidence of increased
oxidative stress and compromised antioxidant defense system in patients with ALD. 相似文献
942.
H. Stead 《Research Policy》1976,5(1):2-9
Since its publication in 1967, the estimates of the US Panel on Invention and Innovation (“Charpie” Panel) on the cost structure of technological innovation have been widely quoted and almost universally accepted. However, two later studies, by Edwin Mansfield and by Statistics Canada, have found that R&D accounts for a far greater proportion of total innovation costs than that suggested by the Charpie Panel. The Canadian study may be particularly interesting for medium-sized industrial nations since it is likely that the costs of commercializing the results of R&D are affected by the size of the potential market or field of utilization of the innovation. The results of Mansfield and Statistics Canada imply that governments, in their encouragement of innovation by supporting R&D, have been following a better strategy than perhaps they knew. 相似文献
943.
944.
945.
Munzir M. E. Ahmed J. A. S. Al-Obosi H. M. Osman M. E. Shayoub 《Indian journal of clinical biochemistry : IJCB》2016,31(2):162-170
Acetaminophen (APAP) a commonly used drug for decrease the fever and pain but is capable to induced hepatotoxicity at over dose. This study was carried out to investigate the effect of APAP on the expression of anti-apoptotic and antioxidative defense genes, and whether aldose reductase over-expressing plasmid capable to protect against APAP-induced oxidative stress and cell death. APAP treatment induced oxidative stress and hepatotoxicity, and significantly increased aldose reductase mRNA and protein expression in mouse hepatocyte (AML-12). Unexpectedly, AML-12 cells over-expressing aldose reductase augmented APAP-induced reduction in cell viability, reactive oxygen species (ROS) production, glutathione (GSH) depletion and glutathione S-transferase A2 expression. Moreover, over-expression of aldose reductase potentiated APAP induced reduction on proliferating cell nuclear antigen, B cell lymphoma-extra large (bcl-xL), catalase, glutathione peroxidase-1 (GPx-1) and abolished APAP-induced B-cell lymphoma 2 (bcl-2) inductions. Further, over-expression of aldose reductase significantly abolished AMP activated protein kinase (AMPK) activity in APAP-treated cells and induced p53 expression. This results demonstrate that APAP induced toxicity in AML-12, increased aldose reductase expression, and over-expression of aldose reductase render this cell more susceptible to APAP induced oxidative stress and cell death, this probably due to inhibition AMPK or bcl-2 activity, or may due to competition between aldose reductase and glutathione reductase for NADPH. 相似文献
946.
Tångeberg P 《Endeavour》2000,24(4):147-151
The seventeenth-century Swedish Royal warship Vasa was painted and decorated with almost 500 figure sculptures and many carved ornaments. It is probably the most extensive sculptural work in wood to have been preserved from this period in European history. The ship's decorations are of particular importance given the scarcity of knowledge of how sculptures in general, and large ships in particular, were painted in Northern Europe during this period. About 20 different pigments have been characterized and it has been possible to reconstruct the appearance of many of the sculptures and to extend this knowledge to the ship's original appearance. 相似文献
947.
Akila V. Prashant H. Harishchandra Vivian D'souza Benedicta D'souza 《Indian journal of clinical biochemistry : IJCB》2007,22(1):131-134
Advanced age is associated with an accumulation of free radical damage, which leads to physiological and clinical modifications.
Age related changes resulting from free radical reactions include increasing levels of lipid peroxides, alterations in enzyme
activities and greater osmotic fragility. The present study was conducted to estimate the level of lipid peroxidation product-Malondialdehyde
and antioxidants Catalase and Glutathione in elderly people. An increase in lipid peroxidation and decrease in antioxidants
was observed in normal elderly people. Highly significant increase in MDA and decrease in antioxidants was observed in elderly
people when complicated with diabetes and hypertension. Supplementation of antioxidants may prevent further oxidative injury
in elderly people. 相似文献
948.
Simple as the outflow clock principle may seem for the measurement of time, its translation into an accurate clock raises formidable technical and conceptual problems. An attempt is made here to reconstruct the Egyptians' consciousness of these problems, and the success of their solutions. 相似文献
949.
Andrew H. Wilson 《Research Policy》1974,2(4):364-379
As a country with a relatively small international reputation for manufacturing and, apparently, with an even smaller one for technology-based product and process innovation in manufacturing, Canada has a long way to go to develop its manufacturing and innovative activities to the stage reached by most European countries. Recently, however, a number of science and research policy studies have been made to examine problems associated with innovation in manufacturing. This present paper deals with two important elements associated with these studies, namely, the organization of the public sector in Canada and the roles and responsibilities of the public sector agencies with regard to the encouragement of technology-based innovation in manufacturing. As pointed out in the paper, the federal structure and the agencies within it may at present frustrate as well as encourage innovation. However, assuming that the appropriate policy objectives can be articulated and accepted, the removal of the principal public sector frustrations will be dependent upon better divisions of responsibility and labour between the three levels of government. 相似文献
950.