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941.
Rukmini M. S. Benedicta D'Souza Vivian D'Souza 《Indian journal of clinical biochemistry : IJCB》2004,19(2):114-118
Free radical mediated pathological processes may have a role in schizophrenia. Free radicals (oxy radicals, such as superoxide,
hydroxyl ions and nitric oxide) cause cell injury, when they are generated in excess or when the antioxidant defense is impaired.
Both these processes seem to be affected in schizophrenia. In this study we investigated erythrocyte superoxide dismutase
(SOD) and catalase (CAT) activities as antioxidant enzymes, malondialdehyde (MDA) as a sign of lipid peroxidation in schizophrenic
patients. Activities of superoxide dismutase, catalase and malondialdehyde were greater in patients compared with the control
group which may reflect increased oxidative stress in the brain tissue of schizophrenics. In the patient group erythrocyte
SOD and CAT activities were weakly negative correlated with MDA concentration. These data reveal that antioxidant defense
mechanisms might be impaired in schizophrenic patients. These findings also provide a theoretical basis for the development
of novel therapeutic strategies, such as antioxidant supplementation. 相似文献
942.
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
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The transport of thermal energy in thermodynamics is described as the product of entropy flow and of the absolute temperature, in analogy to the volume flow and pressure in oil hydraulics and to electric charge flow (= current) and voltage in electronics. Bond graphs are shown to be especially suitable to describe the splitting of applied thermal energy into internal energy and external mechanical work. Transformers and the 0- and 1-junctions of Paynter can illustrate various entropy flow processes, including Carnot engines and heat exchangers. Entropy flow in heat conduction is distinguished from entropy convection, or transport by moving mass, where the entropy/temperature characteristic or equation of state is important. Irreversibilities are represented by impedance transformers reducing temperature and increasing entropy flow but conserving power. 相似文献
946.
Dietary restriction (DR) also called dietary control or calorie restriction is reported to have many advantages with regard
to human health. It leads to suppression of obesity, mitigates free radicals and increases available antioxidants which are
accounted for extending the life span of individuals. DR is also reported to induce synthesis of heat shock proteins in animals
as a control mechanism against stress. Further, it is known to play a significant role in decreasing toxicity and lethality
due to a variety of toxic chemicals and drugs by stimulating tissue repair damaged by the toxicants leading to restoration
of intact organ and its functions. Moreover, extensive work done on animals indicate DR has an important role in suppressing
certain types of cancer. In this review an effort is made to highlight the various advantages of DR from the point of human
health perspective. 相似文献
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In the United States, Congress has had a long-standing interest in consumer privacy and the extent to which company practices are based on fair information practices. Previously, public policy was largely informed by anecdotal evidence about the effectiveness of industry self-regulatory programs. However, the Internet has made it possible to unobtrusively sample web sites and their privacy disclosures in a way that is not feasible in the offline world. Beginning in 1998, the Federal Trade Commission relied upon a series of three surveys of web sites to assess whether organizations post online privacy disclosures and whether these disclosures represent the U.S. definition of fair information practices. While each year's survey has provided an important snapshot of U.S. web-site practices, there has been no longitudinal analysis of the multiyear trends. This study compares a subset of equivalent individual-level web-site data for the 1998, 1999, 2000, and 2001 web surveys. Implications for using this type of research to inform public policy are discussed. 相似文献
950.
Mark Coeckelbergh 《Ethics and Information Technology》2007,9(3):219-231
Many philosophical and public discussions of the ethical aspects of violent computer games typically centre on the relation
between playing violent videogames and its supposed direct consequences on violent behaviour. But such an approach rests on
a controversial empirical claim, is often one-sided in the range of moral theories used, and remains on a general level with
its focus on content alone. In response to these problems, I pick up Matt McCormick’s thesis that potential harm from playing
computer games is best construed as harm to one’s character, and propose to redirect our attention to the question how violent
computer games influence the moral character of players. Inspired by the work of Martha Nussbaum, I sketch a positive account
of how computer games can stimulate an empathetic and cosmopolitan moral development. Moreover, rather than making a general
argument applicable to a wide spectrum of media, my concern is with specific features of violent computer games that make
them especially morally problematic in terms of empathy and cosmopolitanism, features that have to do with the connections
between content and medium, and between virtuality and reality. I also discuss some remaining problems. In this way I hope
contribute to a less polarised discussion about computer games that does justice to the complexity of their moral dimension,
and to offer an account that is helpful to designers, parents, and other stakeholders.
An earlier version of this paper was presented at the ACLA 2006 conference in Princeton, 25 March 2006. 相似文献