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Efficacy of Postoperative Antimicrobial Use for Clean Orthopedic Implant Surgery in Dogs: A Prospective Randomized Study in 100 Consecutive Cases 下载免费PDF全文
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Dana M. Calhoun Paula A. Schaffer Jacklyn R. Gregory Katherine M. Hardy Pieter T. J. Johnson 《Journal of aquatic animal health》2015,27(4):185-191
Infections by the digenetic trematode, Ribeiroia ondatrae, cause severe limb malformations in many North American amphibians. Ribeiroia ondatrae also infects fishes as second intermediate hosts, but less is known about the pathology and immune responses initiated in infected fish, even though reports of infected fish date back to early 1900s. To this end, we experimentally exposed juvenile Bluegills Lepomis macrochirus to three doses of R. ondatrae cercariae and monitored the pathology, parasite infection success, and humoral responses over 648 h. All exposed fish became infected with metacercariae, and the average infection load increased with exposure dose. Histologically, infection was associated with acute hemorrhages in the lateral line and local dermis at 36 h, followed by progressive granulomatous inflammation that led to the destruction of encysted metacercariae. Correspondingly, over the course of 648 h we observed an 85% decline in average infection load among hosts, reflecting the host's clearance of the parasite. Infection was not associated with changes in fish growth or survival, but did correlate with leukocytosis and neutrophilia in circulating host blood. Understanding the physiological responses of R. ondatrae in Bluegill will help to clarify the ecological effects of this parasite and provide a foundation for subsequent comparisons into its effects on behavior, individual health, and population dynamics of Bluegill.
Received March 4, 2015; accepted August 9, 2015 相似文献
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Changes in adherence to cardiopulmonary resuscitation guidelines in a single referral center from January 2009 to June 2013 and assessment of factors contributing to the observed changes 下载免费PDF全文
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The activity and inhibition of poly(ADP‐ribose) polymerase‐1 in equine peripheral blood mononuclear cells in vitro 下载免费PDF全文
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