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971.
The effect of oral administration of vitamin E for twenty-eight consecutive days on blood glucose, reduced glutathione levels, antioxidant enzymes (superoxide dismutase and catalase activities), and levels of malondialdehyde (as an index of free radical-mediated lipid peroxidation) was observed in the whole blood and liver of normal and alloxan-induced diabetic rats. It was found that oral administration of vitamin E significantly (p<0.05) lowered the blood glucose level and increased the body weight of the diabetic rats. The activities of superoxide dismutase and levels of reduced glutathione increased significantly (p<0.05) while the level of lipid peroxidation decreased.  相似文献   
972.
In order to investigate the effect of methods of teaching on achievement in mathematics of first year National Certificate of Education (NCE) students in Nigeria, a sample of 165 students comprising 71 males and 94 females, was exposed to three methods of teaching in a second semester basic mathematics course. The three methods were the traditional lecture method, interactive method with individual use of materials and interactive method with group use of materials. Analysis of covariance showed a significant interactive effect of gender and method of teaching on student achievement. Further analysis showed that the use of interactive methods with group use of materials favoured males while interactive method with individual use of materials favoured females. Implications of the results for teaching of tertiary mathematics are discussed. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
973.
First- and 3rd-year university students were surveyed regarding cultural attitudes and climate. Comfort in cross-cultural situations and respect for other cultures correlated with overall satisfaction for all students. However, the more Asian Americans, Hispanic Americans, and Whites were aware of diversity and changing their behavior accordingly, the less satisfied they were. Awareness of diversity was not related to overall satisfaction for African Americans.  相似文献   
974.
Little is known about how animals represent their own actions in working memory. We investigated whether bottlenosed dolphins could recall actions they had recently performed and reveal those recollections using an abstract rule. Two dolphins were trained to respond to a specific gestural command by repeating the last behavior performed. Both dolphins proved to be able to repeat a wide variety of behaviors on command and were able to generalize the repeating rule to novel behaviors and situations. One dolphin was able to repeat all 36 behaviors she was tested on, including behaviors involving multiple simultaneous actions and self-selected behaviors. These results suggest that dolphins can flexibly access memories of their recent actions and that these memories are of sufficient detail to allow for reenactments. The repeating task can potentially be used to investigate short-term action and event representations in a variety of species.  相似文献   
975.
In view of sufficient body of evidence to substantiate the role of free radical mediated oxidative injury in myocardial infarction (M.I.), the utility of exogenous supplementation with antioxidant substance, vitamin E was studied. Forty patients of acute myocardial infarction were divided into two equal groups, one who received vitamin E and the other who did not. Plasma MDA levels showed a reduction in patients of M.I. who received vitamin E as well as in those who did not, however, the decrease was significantly more in the vitamin E treated subgroup.  相似文献   
976.
The purpose of the study was to determine the attitudes of Hindu students from a government women's college of South India toward people with AIDS, to assess their beliefs about HIV/AIDS, to determine their knowledge level about HIV/AIDS and to determine how they gain information about HIV/AIDS. The sample consisted of four hundred female students at a government funded Women's University in Southern India who participated in an AIDS survey research project. Participants completed a survey asking about their knowledge, attitudes and beliefs about HIV/AIDS. Results indicated that a majority of the participants learned about HIV/AIDS from reading material while some learned about HIV/AIDS from school classes, and only a few learned from family members. Thirty-nine percent had never communicated to any one about HIV/AIDS. The results indicated that the majority of Indian women in this study did not know about explicit sexual behaviors which transmit the virus. The study also showed that those Indian women university students, by and large, are accepting of people with AIDS but still have fears of getting HIV/AIDS. This data suggest a need to increase educational efforts at the university. It was suggested that counselors take responsibility for helping this population of Indian women become self advocates, particularly in a society which permits men to have multiple sexual relationships. Educators and counselors working with this population must initiate programs that impart accurate and specific knowledge to these female college students and begin to address the multiple psychosocial issues related to HIV/AIDS.  相似文献   
977.
The essay describes the development of Hugo de Vries's thinking on heredity from the publication of his Intracellulare Pangenesis in 1889 to the publication of Die Mutations-theorie, Volume 2, in 1903. De Vries's work in the 1890s can be characterized as an attempt to defend his theory of pangenes, especially the fundamental and controversial idea that different characters have different material hereditary carriers. Hybridization experiments served his goal. Recently discovered research notes on hybridization from 1896 suggest that, though he was unaware of Mendel's work, De Vries used the laws of dominance and recessiveness, segregation, and independent assortment to explain the 75:25 ratio in the second generation. He had discovered these laws by applying insights from probability theory to his research. In Die Mutationstheorie De Vries combined central concepts of intracellular pangenesis and his mutation theory by modifying the meanings of important terms and introducing new states of pangenes. In his attempts to describe Mendelian crossings in terms of pangenes and mutations, he became entangled in a number of contradictions. Some of his remarks suggest that he was aware that the Mendelian laws and his own theories of pangenes and mutations could not be made consistent.  相似文献   
978.
We present our observation of meta-hydrophobicity, where geometrically patterned surfaces make hydrophilic microchannels exhibit hydrophobic-like behaviors. We analyze the wetting-induced energy decrease that results from the surface geometries and experimentally demonstrate how those geometries can modulate the dynamics of capillary-driven wetting and evaporation-driven drying of microfluidic systems. Our results also show that the modulated wetting dynamics can be employed to generate regulated patterns of microbubbles.  相似文献   
979.
The behavior of a class of hybrid systems in discrete-time can be represented by nonlinear difference equations with a Markov input. The analysis of such a system usually starts by establishing the Markov property of the joint process formed by combining the system's state and input. There are, however, no complete proofs of this property. This paper aims to address this problem by presenting a complete and explicit proof that uses only fundamental measure-theoretical concepts.  相似文献   
980.
Activities of human hepatic drug metabolizing enzymes N-acetyl transferase (NATS) had earlier been recognized as a cause of inter-individual variation in the metabolism of drugs. Therefore acetylation of many drugs in human exhibit genetic polymorphism. The aim of the study was to investigate if acetylator status predispose diabetic mellitus patients more to the complications of renal disease, One hundred and twenty (120) diabetics consisting of (50) Type 1 (T1) and 70 Type 2 (T2) diabetes mellitus patients and 100 healthy individuals as controls were classified as slow or rapid acetylator using sulphamethazine (SMZ) as an in vivo probe. The percentage acetylation, recovery of SMZ, creatinine clearance and presence of urinary albumin were determined. A significant difference (P < 0.05) was observed in the percentage of SMZ acetylated between slow and rapid acetylators in control, T1 and T2 subjects. The ratios of slow to rapid acetylators for T1, T2 and control subjects were 1:4, 3:2 and 2:3 respectively. No significant differences were observed in the percentage of SMZ recovered in the urine of slow and rapid acetylators that are diabetics. The difference in creatinine clearance of slow and rapid acetylators in T1 and T2 were significant (P < 0.05). 29% out of 120 (24.2%) diabetics (T1 and T2) exhibited albuminuria out of which 25 (86.2%) had slow acetylator status. These findings suggest that slow acetylator status in diabetes mellitus could be a predisposing factor in the development of renal complications. This underscores the need for a rapid pharmacogenetic testing and therapeutic drug monitoring in such patients. However this inference could be further validated with a larger sample size.  相似文献   
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