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91.
New, except 1d, melatonin analogue benzimidazole derivatives were synthesized and characterized in the present study. The potential role of melatonin as an antioxidant by scavenging and detoxifying ROS raised the possibility that compounds that are analogous to melatonin can also be used for their antioxidant properties. Therefore the antioxidant effects of the newly synthesized compounds were investigated in vitro by means of their inhibitory effect on hydrogen peroxide-induced erythrocyte membrane lipid peroxidation (EMLP) and on various erythrocyte antioxidant enzymes viz. superoxide dismutase (SOD), catalase (CAT) and glucose-6-phosphate dehydrogenase (G6PD). The synthesized benzimidazole derivatives showed remarkable antioxidant activity in vitro in the H2O2-induced EMLP system. Furthermore their effects on various antioxidant enzymes are discussed and evaluated from the perspective of structure- activity relationships.  相似文献   
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The Pecten, considered from an Environmental Point of View.   总被引:1,自引:0,他引:1  
Arthur  Thoyson F.R.C.R.  LL.D.  D.C.L. 《Ibis》1929,71(4):608-639
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In 1950, Raphael Patai published his research on Venta Prieta, a Mexican town in which some residents lived as Jews despite having little knowledge of Judaism. Like other visitors, Patai was perplexed. Why did they wish to live as Jews? While Patai never answered this question to his satisfaction, he believed the answer would be found by developing a psychological profile of the residents, an approach in keeping with culture and personality theorists of the day. The present article provides a different solution. Drawing on additional sources, and short visits, we argue that Venta Prieta was not only a stop on the Jewish tourist circuit by 1950 but also developed out of a unique exchange. While U.S. Jews, as evangelical Protestants before them, provided a model for upwardly mobile Mexicans, Venta Prieta enabled middle-class tourists to experience Judaism in a pastoral setting and to "repair the world" (tikkun). [Keywords: Judaism, tourism, dialogical anthropology, social change, social mobility]  相似文献   
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Genetic assignment methods provide an appealing approach for characterizing dispersal patterns on ecological time scales, but require sufficient genetic differentiation to accurately identify migrants and a large enough sample size of migrants to, for example, compare dispersal between sexes or age classes. We demonstrate that assignment methods can be rigorously used to characterize dispersal patterns in a marbled murrelet (Brachyramphus marmoratus) population from central California that numbers approximately 600 individuals and is only moderately differentiated (FST~ 0.03) from larger populations to the north. We used coalescent simulations to select a significance level that resulted in a low and approximately equal expected number of type I and II errors and then used this significance level to identify a population of origin for 589 individuals genotyped at 13 microsatellite loci. The proportion of migrants in central California was greatest during winter when 83% of individuals were classified as migrants compared to lower proportions during the breeding (6%) and post‐breeding (8%) seasons. Dispersal was also biased toward young and female individuals, as is typical in birds. Migrants were rarely members of parent‐offspring pairs, suggesting that they contributed few young to the central California population. A greater number of migrants than expected under equilibrium conditions, a lack of individuals with mixed ancestry, and a small number of potential source populations (two), likely allowed us to use assignment methods to rigorously characterize dispersal patterns for a population that was larger and less differentiated than typically thought required for the identification of migrants.  相似文献   
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Background  

Schistosoma mansoni is a blood fluke that infects approximately 90 million people. The complete life cycle of this parasite can be maintained in the laboratory, making this one of the few experimentally tractable human helminth infections, and a rich literature reveals heritable variation in important biomedical traits such as virulence, host-specificity, transmission and drug resistance. However, there is a current lack of tools needed to study S. mansoni's molecular, quantitative, and population genetics. Our goal was to construct a genetic linkage map for S. mansoni, and thus provide a new resource that will help stimulate research on this neglected pathogen.  相似文献   
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