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Birds of prey have demonstrated the negative impact that toxic agents can cause on animal populations and ecosystem dynamics. Lead, cholinesterase inhibitors (eg, organophosphates, carbamates), and anticoagulant rodenticides (eg, brodifacoum) are the most common toxic agents that currently affect the health of wild birds of prey in the United States. For raptors held in captivity, the list of toxic agents expands and includes toxic inhalants such as carbon monoxide and polytetrafluoroethylene. This article provides diagnostic and treatment guidelines for the toxic agents discussed.  相似文献   
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Exploiting a randomized natural experiment in India, we show that female leadership influences adolescent girls' career aspirations and educational attainment. A 1993 law reserved leadership positions for women in randomly selected village councils. Using 8453 surveys of adolescents aged 11 to 15 and their parents in 495 villages, we found that, relative to villages in which such positions were never reserved, the gender gap in aspirations closed by 20% in parents and 32% in adolescents in villages assigned a female leader for two election cycles. The gender gap in adolescent educational attainment was erased, and girls spent less time on household chores. We found no evidence of changes in young women's labor market opportunities, which suggests that the impact of women leaders primarily reflects a role model effect.  相似文献   
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Cynomolgus macaques (also known as longtail or crab-eating macaques) Macaca fascicularis, are an important non-human primate model for biomedical research. Using a case study involving a suspected occurrence of twin birth, we demonstrate that the highly polymorphic human variable-number tandem repeat (VNTR) mini-satellite probes D1S7, D2S44, D3S42 and D4S184 can be successfully employed as a rapid screening strategy to complement husbandry records in order to establish genetic relatedness in a captive colony.  相似文献   
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Populations of Choristoneura rosaceana (Harris) from orchards in Ontario were shown to be resistant to azinphos-methyl and to other types of organophosphorus insecticides. Resistance extended to methyl carbamates and to methomyl. The laboratory population used for these assays and selected with azinphosmethyl was also resistant to the pyrethroid, cypermethrin. Resistance was associated with increased esterase activity and was reduced by the addition of the synergist DEF. IEF studies of esterases also indicated increased activity in resistant populations, but did not identify any unique esterases associated with the resistance. Resistance was highly correlated (r = 0.78) with elevated esterases but not with increased glutathione-S transferase activity (r = 0.13). Other mechanisms did not appear to be related.  相似文献   
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