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991.
A performance index consisting of a Chebyshev absolute maximum functional plus terminal and integral cost is applied to the optimal control of dynamical systems. First-order necessary conditions are derived for a large class of systems. Utilizing the necessary conditions, analytic examples are worked in demonstrating many of the properties of this class of systems. 相似文献
992.
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
993.
Ajay Kumar T. A. Venkita Subramanian Usha P. Sharma 《Indian journal of clinical biochemistry : IJCB》1992,7(2):165-168
Protein fraction termed P2 was obtained from sonicates of Mycobacterium smegmatis, subjected to ammonium sulphate precipitation. P2 fraction was further fractionated into 4 fractions (PeakI-IV) by DEAE cellulose ion-exchange chromatography. ELISA was performed
on the sera of 104 tuberculous cases and 62 controls, using P2 fractions Peak I as test antigens. Though the mean ELISA values in tuberculous cases were higher than the controls, no statistically
significant difference was found between the two. Antigens P2, Peak I and IV were tested on Western blots with pooled sera from tuberculous cases as well as controls. P2 fraction, Peak-I and IV were separated on PAGE-SDS, electroblotted onto nitrocellulose Sheets and the blots were subjected
to ELISA. Peak IV appeared as a single band (M.W. 55,000). P2 fraction exhibited some discriminatory bands on development of blots. 相似文献
994.
995.
996.
Ishrat Kareem S. A. Jaweed J. S. Bardapurkar V. P. Patil 《Indian journal of clinical biochemistry : IJCB》2004,19(2):124-127
The present study was undertaken in 100 subjects, 30 diabetics without complication (group I), 40 diabetics with retinopathy
(group II) and 30 non diabetic as normal control group (group III). Blood sugar levels, magnesium, cholesterol and triglyceride
were analyzed from plasma and serum. The results were correlated with degree of diabetic control from the levels of glycosylated
hemoglobin. Serum magnesium levels in group II were found to be significantly lowered than in group I. There was also significant
difference in magnesium levels of group I and group III. We found a significant correlation between the glycosylated hemoglobin
and magnesium levels in our study.
The results also indicate that the patients with diabetic retinopathy showed significant rise in serum cholesterol and triglyceride.
Probably hypomagnesemia and increased serum cholesterol and triglyceride levels are responsible for microvascular changes
in diabetes leading to retinopathy. The purpose of this study was thus to gather information about the degree of control of
diabetes and magnesium status. 相似文献
997.
998.
M. V. R. Reddy R. Alli B. C. Harinath 《Indian journal of clinical biochemistry : IJCB》2000,15(1):127-135
Lymphatic filariasis caused mainly by infection fromWuchereria bancrofti andBrugia malayi remains as the major cause of clinical morbidity in tropical and subtropical countries. Development of vaccine against filarial infection can act as additional measure to the existing therapeutic and vector control methods in the control of this disease. The main hurdles in the development of anti-filarial vaccine are the strict primate specificity ofWuchereria bancrofti, the paucity of parasite material, the diversity of clinical manifestations and their associated complex immune responses, lack of clear understanding on host-parasite interactions and the mechanisms involved in protective immunity. However in the past few years, the information generated in immuno-epidemiological studies, correlated with observations in experimental animals suggests that a filarial vaccine is feasible. Initially live irradiated infective larvae have been successfully used to induce high level of protective immunity in several animal models. Applying diverse strategies, variety of purified or recombinant filarial antigens have been explored for their ability to induce protection in different host-parasite systems. Some of these targeted filarial antigens induced high level of resistance in experimental animals against challenge infections. More focussed studies on thorough characterization of parasitological and immunological changes associated with resistance induced by such candidate protective antigens and on delivery mechanisms and safety aspects will be crucial in their selection for possible use in humans. 相似文献
999.
Curcumin is a natural anti-inflammatory and antioxidant with several potential health benefits. Although it has been examined in several metals toxicity studies, but its role in the protection against copper toxicity has not been investigated. In this study; the detoxification and antioxidant effect of curcumin were examined to determine its prophylactic/therapeutic role experimentally in rats. Forty albino rats were divided into five groups; control, CuSO4 (4 mg/kg body weight), curcumin (80 mg/kg body weight), curcumin post-treatment (CuSO4 for 15 days followed by curcumin for the next 15 days) and curcumin co-treatment (CuSO4 plus curcumin for 30 days). All rats were treated orally by stomach tube for 30 days/once a day. Changes were observed in hepatic marker enzymes such as: aspartate aminotransferase (AST), alanine transaminase-(ALT), alkaline phosphatase (ALP) and gamma-glutamyltransferase (GGT), besides the serum total protein, urea and creatinine. Concentration of liver and kidney antioxidants such as: catalase (CAT), superoxide dismutase (SOD), reduced glutathione-(GSH) and malondialdehyde (MDA) were measured. An increased in the activities of liver marker enzymes, urea, creatinine and the MDA contents were detected after exposure to CuSO4. Meanwhile, the activities of serum total protein, hepatic and renal antioxidants were decreased. Changes in all biochemical parameters were alleviated by the post-treatment and co-treatment of curcumin. Our finding suggests that the curcumin showed protective effects on CuSO4-induced hepatotoxicity and nephrotoxicity. 相似文献
1000.
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