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971.
972.
Ramesh Chander A. K. Khanna Kanwal Raj A. K. Rastogi 《Indian journal of clinical biochemistry : IJCB》2005,20(1):153-159
Indian black tea; CTC leaf and dust, produced by Tata Tea Limited, Kolkata, (India) was studiedin vitro as potential scavenger of oxygen free radicals. Super oxide anions were generated in a system containing xanthine—xanthine
oxidase (enzymic system) and by NADH- phenozine methosulphate (non enzymic system). Anions were assayed in terms of uric acid
formation and reduction of nitroblue tetrazolium salt, which were shown to be suppressed by tea extracts. Extracts from both
leaf and dust also inhibted the formation of hydroxyl radicalsin vitro in the enzymic system comprising hypoxanthine—Cu+2—sodium ascorbate and xanthine oxidase and in non enzymic system of deoxyribose—Cu+2—sodium ascorbate and H2O2 as well as the Cu+2 induced lipid peroxidation in human low density lipoprotein. Feeding with black tea in normal rats for sixty days increased
their antioxidant activity and their liver microsomes were shown to be protected against peroxidation of lipids as stimulated
by metal ions with enzymic or non enzymic reactants. Furthermore feeding with tea extracts in normal as well as triton WR—1339
induced hyperlipidemic rats caused decrease in their plasma levels of total cholesterol, phospholipids and triglycerides.
The antioxidant and lipid lowering activities of both extracts from CTC leaf and dust tea was comparable and may be due to
the presence of natural products like catechin and others. 相似文献
973.
Oliver K. Burmeister 《Ethics and Information Technology》2016,18(3):185-198
Developing technology that accounts for values has been achieved in many areas, including security, gaming, finance, engineering, and many more. The main methodological approach has been that of value sensitive design. But most of the work to date has been on the first of its three stages. The focus of this article is on advances related to its second stage, empirical investigation, and in particular the impact of contextual understanding in that stage. Although lessons can be learnt from other domains, the specific context of dementia means that there are nuances to understanding values, including justice and autonomy, that differ from other areas. The integration of value considerations in the development of assistive technology in dementia is explored in two broad categories: the traditional and ongoing need for fixed decision support, and adaptable decision support technologies. For fixed decision support the A&D Benchmark is particularly useful in design. But for adaptable technologies, that benchmark requires further development, including consideration of the values of additional stakeholders, such as the general public. 相似文献
974.
K. Poornima M. Cariappa K. Asha H. P. Kedilaya M. Nandini 《Indian journal of clinical biochemistry : IJCB》2003,18(2):197-205
An adequate antioxidant reserve which is usually present in a vegetarian diet is associated with higher life expectancy. On
the other hand habitual consumption of fish is associated with lower risk of cardiovascular diseases which is attributed to
the polyunsaturated fatty acids (PUFA) present in it. However the PUFA are readily susceptible to oxidation leading to the
formation of free radicals which is known to be involved in the causation of several diseases.
The oxidant-antioxidant status of 23 vegetarians and 22 fish eaters was studied by determining the plasma lipid peroxides
measured as malondialdehyde (MDA) and the antioxidants, viz. glutathione (GSH), ascorbic acid, ceruloplasmin and uric acid.
Results show that the ascorbic acid values were significantly higher in vegetarians. In addition, MDA correlated negatively
with ascorbic acid only in vegetarians. However, correlation of MDA with glutathione showed a significant negative correlation
only in fish eaters. There was no statistically significant difference in the MDA, GSH, ceruloplasmin and uric acid levels.
The mechanism behind these findings are not clear and needs to be explored. 相似文献
975.
Pernilla Gripenberg Ingjerd Skogseid Francesco Botto Andrea Silli Virpi Kristiina Tuunainen 《The Information Society》2004,20(1):3-14
This article compares four European information and communication technologies (ICT) development projects spawned by national and EU initiatives to create the “European information society.” These projects, which sought to support learning and better use of ICT, were all the result of opportunities opened up by political initiatives. The analysis indicates that the main problems that afflict these projects stem from varied expectations and interests of the major actors. These problems can be mitigated considerably if a feeling of ownership is generated among the participants. This sense of belonging, however, is difficult to foster in a “top-down” project. Hence there is a need for a better balance between the “top-down” and “bottom-up” influences in the development of such projects. 相似文献
976.
977.
This paper presents the applications of the stability-equation method to the analysis and design of linear systems. Control systems with multiple inputs and outputs are considered; the absolute stability and relative stability characteristics are analyzed. Stability conditions for control systems with a transport lag or a distributive lag are presented. Finally, the stability characteristics of a system with a distributive parameter are analyzed. 相似文献
978.
The level of sialic acid in the obese polymorphonuclear leukocytes (PMNL) was found to be significantly reduced as compared to normal. Activity of sialic acid degrading enzyme, sialidase, was found to be increased in the obese state. Restoration in both sialic acid content and sialidase activity was also evidenced in the PMNL of treated obese patients. 相似文献
979.
Biswajit Majumdar Susri Ray Chaudhuri Arun Ray Sandip K Bandyopadhyay 《Indian journal of clinical biochemistry : IJCB》2002,17(1):49-57
Pretreatment of an ethanolic extract of leaf ofPiper betle linn at a dose of 200mg/kg body weight, orally administered to rats for ten consecutive days, was found to possess a significant
protective action against gastric lesions induced by indomethacin. The extract pretreatment resulted in significant increase
in superoxide dismutase (SOD) and catalase (CAT) activity, increase in mucus, hexosamine and total thiol group content, but
marked reduction in oxidatively damaged protein and peroxidised lipid levels as compared to untreated ulcerated control. The
extract was also found to possess both superoxide and hydroxyl free radical scavenging action. The present observations establish
the efficacy of the extract in prevention of experimentally induced peptic ulcer by indomethacin and antioxidant property
appears to be predominantly responsible for such cytoprotective activity in the experimental model. 相似文献
980.
A method has been presented in recent papers for deriving precisely stabilized waveform generators by relating them to second-order conservative oscillators. The present paper suggests a method for considerably generalizing the previous class ofgenerator models. This should enable the development of a larger variety of waveform generators with ease and flexibility. The new method is analyzed and is shown to possess implications to theoretical biology and other fields. 相似文献