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91.
Maarten J Voordouw Doug Adama Barb Houston Purnima Govindarajulu John Robinson 《BMC ecology》2010,10(1):6
Background
Emerging infectious diseases threaten naïve host populations with extinction. Chytridiomycosis, an emerging infectious disease of amphibians, is caused by the pathogenic fungus Batrachochytrium dendrobatidis (Bd) and has been linked to global declines in amphibians.Results
We monitored the prevalence of Bd for four years in the Northern leopard frog, Rana pipiens, which is critically imperiled in British Columbia (BC), Canada. The prevalence of Bd initially increased and then remained constant over the last three years of the study. Young of the year emerging from breeding ponds in summer were rarely infected with Bd. Some individuals cleared their Bd infections and the return rate between infected and uninfected individuals was not significantly different.Conclusions
The BC population of R. pipiens appears to have evolved a level of resistance that allows it to co-exist with Bd. However, this small population of R. pipiens remains vulnerable to extinction.92.
Howard AW Marcy GW Johnson JA Fischer DA Wright JT Isaacson H Valenti JA Anderson J Lin DN Ida S 《Science (New York, N.Y.)》2010,330(6004):653-655
The questions of how planets form and how common Earth-like planets are can be addressed by measuring the distribution of exoplanet masses and orbital periods. We report the occurrence rate of close-in planets (with orbital periods less than 50 days), based on precise Doppler measurements of 166 Sun-like stars. We measured increasing planet occurrence with decreasing planet mass (M). Extrapolation of a power-law mass distribution fitted to our measurements, df/dlogM = 0.39 M(-0.48), predicts that 23% of stars harbor a close-in Earth-mass planet (ranging from 0.5 to 2.0 Earth masses). Theoretical models of planet formation predict a deficit of planets in the domain from 5 to 30 Earth masses and with orbital periods less than 50 days. This region of parameter space is in fact well populated, implying that such models need substantial revision. 相似文献
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Christine F. Murray Doug M. Veira Audrey L. Nadalin Deborah M. Haines Marion L. Jackson David L. Pearl Ken E. Leslie 《Canadian journal of veterinary research》2015,79(2):109-119
The objective of this study was to examine the effect of calving difficulty or dystocia on the vitality of newborn calves and its association with blood pH, the apparent efficiency of immunoglobulin G (IgG) absorption (AEA), and weight gain. A total of 45 calving events (N = 48 calves) were monitored from the first sight of fetal membranes. All calves were assessed at the time of first attaining sternal recumbency (SR), at 2 and 24 h, and at 7 and 14 d of age. Measurements included time to SR, rectal temperature, respiration and heart rate, analysis of blood gases and other blood measures, suckling response, time to standing, passive transfer of IgG, and weight gain. Calves were separated from their dam 2 h after birth and fed a commercial colostrum replacer containing 180 g of IgG by esophageal tube feeder. Calves born following dystocia had lower venous blood pH and took longer to attain SR and attempt to stand than those born unassisted. Duration of calving interacted with the number of people required to extract the calf by pulling as a significant predictor of pH at SR. No association was found between pH at SR and AEA. However, reduced AEA was found in calves that were female and in calves that did not achieve SR within 15 min of birth. A longer calving duration, being born in July or August rather than June, and a shorter time spent standing in the first 2 d of life were significantly associated with reduced weight gain to 14 d. It was concluded that factors at calving impact the physiology, vitality, and subsequent weight gain of newborn calves. 相似文献
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Switching NSAIDs in practice: insights from the Previcox (firocoxib) Experience Trial 总被引：1，自引：0，他引：1
Ryan WG Moldave K Carithers D 《Veterinary therapeutics : research in applied veterinary medicine》2007,8(4):263-271
Veterinarians currently have a choice of six registered NSAIDs for use in the management of canine osteoarthritis. There is a need for data to clarify whether there is an increased risk of side effects occurring in the event of a switch between different members of the NSAID class. In this retrospective analysis of extensive data collected in the 1,000 dog Previcox (firocoxib, Merial) Experience Trial, the incidence of side effects in dogs reported as treated with an NSAID 7 days or less before enrollment was compared with that in dogs reported as not having received an NSAID in the equivalent period. Statistical analysis of the data indicates that observation of an interval of up to 1 week between beginning treatment with firocoxib and cessation of treatment with a different NSAID was not associated with any increased risk of adverse events. 相似文献