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991.
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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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   
994.
Infertility is well-established harmful effect in chronic alcoholism and so far, there is no effective treatment for this condition. The study was conducted to determine the effects of alpha tocopherol on ethanol induced testicular injuries in male albino rats of Wistar strain. Five groups (n=6) of animals were used. Group I served as control. Group II received daily 1.6g ethanol/kg body weight/day for 4 weeks orally. Group III received 1.6g ethanol+80mg alpha tocopherol/kg body weight/day for four weeks orally. Group IV received 1.6g ethanol/kg body weight for/day 4 weeks and followed by 80mg alpha tocopherol/kg body weight/day for four weeks orally. Group V received 1.6g ethanol/kg body weight/day orally for 4 weeks, followed by 4 weeks abstinence. Twently-four hours after the last treatment the rats were sacrificed using anesthetic ether. Testes were removed and used for the estimation of extent of lipid peroxidation and tissue levels of antioxidants and steroidogenic enzymes. Alpha tocopherol treatment increased the activities of testicularΔ 5, 3β-HSD. Moreover, the treatment was also associated with significant decrease in testicular oxidative stress. Ethanol-induced oxidative stress and decreased steroidogenesis can be reversed by treatment with alpha tocopherol.  相似文献   
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This study is designed to isolate and purify a novel anti-clotting protein component from the venom of Enhydrina schistosa, and explore its biochemical and biological activities. The active protein was purified from the venom of E. schistosa by ion-exchange chromatography using DEAE-cellulose. The venom protein was tested by various parameters such as, proteolytic, haemolytic, phospholipase and anti-coagulant activities. 80 % purity was obtained in the final stage of purification and the purity level of venom was revealed as a single protein band of about 44 kDa in SDS-polyacrylamide electrophoresis under reducing conditions. The results showed that the Potent hemolytic activity was observed against cow, goat, chicken and human (A, B and O positive) erythrocytes. Furthermore, the clotting assays showed that the venom of E. schistosa significantly prolonged in activated partial thromboplastin time, thrombin time, and prothrombin time. Venomous enzymes which hydrolyzed casein and gelatin substrate were found in this venom protein. Gelatinolytic activity was optimal at pH 5–9 and 1H NMR analysis of purified venom was the base line information for the structural determination. These results suggested that the E. schistosa venom holds good promise for the development of novel lead compounds for pharmacological applications in near future.  相似文献   
998.
Are preservice teachers prepared to teach struggling readers?   总被引:1,自引:0,他引:1  
Reading disabilities such as dyslexia, a specific learning disability that affects an individual’s ability to process written language, are estimated to affect 15–20% of the general population. Consequently, elementary school teachers encounter students who struggle with inaccurate or slow reading, poor spelling, poor writing, and other language processing difficulties. However, recent evidence may suggest that teacher preparation programs are not providing preservice teachers with information about basic language constructs and other components related to scientifically based reading instruction. As a consequence preservice teachers have not exhibited explicit knowledge of such concepts in previous studies. Few studies have sought to assess preservice teachers’ knowledge about dyslexia in conjunction with knowledge of basic language concepts. The purpose of the present study was to examine elementary school preservice teachers’ knowledge of basic language constructs and their perceptions and knowledge about dyslexia. Findings from the present study suggest that preservice teachers, on average, are able to display implicit skills related to certain basic language constructs (i.e., syllable counting), but fail to demonstrate explicit knowledge of others (i.e., phonics principles). Also, preservice teachers seem to hold the common misconception that dyslexia is a visual perception deficit rather than a problem with phonological processing. Implications for future research as well as teacher preparation are discussed.  相似文献   
999.
This article examines a common problem in higher education – how to create more widespread use of improved practices, often commonly referred to as innovations. I argue that policy models of scale-up are often advocated in higher education but that they have a dubious history in community development and K-12 education and that higher education leaders should shirk policymakers’ push to use a scale-up model of change. These thoughts are conceptual and are based upon a critical review of literature in community development and K-12, but I also draw upon empirical data in reviewing examples of widespread use of innovations in higher education.  相似文献   
1000.
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