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Using data on waterfowl band recoveries, we identified spatially explicit hotspots of concentrated waterfowl movement to predict occurrence and spatial spread of a novel influenza A virus (clade 2.3.4.4) introduced from Asia by waterfowl from an initial outbreak in North America in November 2014. In response to the outbreak, the hotspots of waterfowl movement were used to help guide sampling for clade 2.3.4.4 viruses in waterfowl as an early warning for the US poultry industry during the outbreak . After surveillance sampling of waterfowl, we tested whether there was greater detection of clade 2.3.4.4 viruses inside hotspots. We found that hotspots defined using kernel density estimates of waterfowl band recoveries worked well in predicting areas with higher prevalence of the viruses in waterfowl. This approach exemplifies the value of ecological knowledge in predicting risk to agricultural security.  相似文献   
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Exhaled nitric oxide (FENO) is raised in atopy. The mechanism for this is unclear. The aim of this study was to investigate whether the number of AAT repeats in intron 20 of the NOS1 gene, recently associated with variations in FENO in adults with asthma and cystic fibrosis, was associated with the raised FENO in healthy atopic children. Eighty-seven healthy children (44 girls, 42 atopic, age range 6–18 years) underwent measurements of FENO, spirometry, airway responsiveness and skin prick testing. Genotyping was carried out to determine the number of AAT repeats. There was no association between the number of AAT repeats and FENO in either the whole sample of healthy children (n = 87) or in the subsample of healthy atopics (n = 42). However, a greater number of atopic children had two high repeat alleles compared with non-atopic children (33.3% vs. 13.6%, respectively, p = 0.03). This suggests that variations in the NOS1 gene may contribute to atopy without this relationship being reflected by FENO.  相似文献   
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Tissue distribution studies, utilizing whole-body autoradiography and organ dissection techniques, were conducted in male Fischer 344 rats following the oral administration of 14C-dapoxetine HCl, a potent serotonin reuptake inhibitor. The preliminary study using whole-body autoradiography proved invaluable in locating radioactivity in an organ not usually harvested in a tissue distribution study, namely the preputial gland. Selected organs, based on whole-body autoradiography findings, were dissected from rats and analyzed for radiocarbon content by liquid scintillation counting and for parent drug and N-dealkylated metabolites by extraction and HPLC analysis. Highest concentrations of radiocarbon were observed in the organs of absorption and elimination (ileum, cecum, stomach, duodenum, liver, colon, and kidney) but notable quantities were observed in the lung and preputial and Harderian glands. Most tissues had returned to background radioactive levels 72 h after dosing but persistent concentrations of radiocarbon were present in the preputial gland and liver one week after the single dose of 14C-dapoxetine. Analysis by HPLC demonstrated the presence of parent drug and N-desmethyl metabolite (nor-dapoxetine) in those organs examined; however, the majority of the radioactivity remained unidentified.  相似文献   
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Three antimycotic N-substituted imidazoles, clotrimazole, tioconazole and miconazole, were able to induce hepatic microsomal cytochrome P-450 and monooxygenase reactions in both male and female hamsters to an extent similar to that seen with phenobarbital treatment. Imidazole treatment did not alter the cytochrome P-450 concentration, and ketoconazole treatment decreased it. Cytosolic sulfo- and glutathione transferases were not significantly altered by any imidazole. Induction of microsomal morphine glucuronosyltransferase activity by each compound generally paralleled the effect on cytochrome P-450 in females but induction was not evident in males. Clotrimazole treatment, in contrast to phenobarbital treatment, also caused a large induction of l-naphthol glucuronosyltransferase in females. The potential for antimycotic imidazoles to alter the hepatotoxicity of compounds will require consideration of the inductive changes in both Phase I and Phase II drug metabolizing enzymes in addition to their known inhibitory effects on Phase I oxidations. The inductive effects differ for each imidazole, and in the hamster model, depend upon the sex of the animal.  相似文献   
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Final year residents in training in Louisiana were surveyed regarding plans for medical practice and their perceptions of the importance of various factors in choosing practice locations. Most specialty groups selected smaller communities at similar rates. Growing up in small towns is associated with wanting to practice in small towns while concerns about opportunities for the family and income of the region are associated with wanting to practice in a larger city.This study was supported by the Louisiana Council for Statewide Planning for Physician Manpower through Contract No. 23058, Louisiana Department of Health and Human Resources.Ms. Samaha is a data analyst for the Louisiana Council for Statewide Planning for Physician Manpower; Robert R. Franklin, M.D. is Executive Secretary of the Council and Assistant Professor, Department of Biostatistics and Epidemiolgy, Tulane University School of Public Health and Tropical Medicine; Janet C. Rice is Assistant Pofessor, Department of Biostatistics and Epidemiology at the Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana 70112.  相似文献   
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