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Sally E. Henderson Sara C. Pfeiffer Joseph Novak Tracy A. Peace 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2020,49(3):382-388
A 5.25-year-old cynomolgus macaque (Macaca fascicularis) was found to have a marked leukocytosis due to a lymphocytosis on routine quarantine laboratory data prior to inclusion in a preclinical research study. The majority of lymphocytes were characterized as intermediate to large with round to convoluted nuclei, coarse to clumped chromatin, rare prominent nucleoli, and moderate amounts of lightly basophilic cytoplasm that frequently contained small magenta granules and/or clear vacuoles. The animal had tested negative for several viruses and other etiologic agents found in nonhuman primates 1 week prior to shipment to the research facility. However, further evaluation of the blood smear revealed rare hemoflagellates, and later testing using real-time PCR and ELISA was confirmatory for Trypanosoma cruzi (T cruzi). Trypanosoma cruzi is a zoonotic pathogen responsible for Chagas disease in people and can have negative consequences on study results when positive animals are inadvertently used for preclinical research. This case report describes a marked large granular lymphocytosis in an otherwise healthy macaque as the only indication of infection with T cruzi in an animal believed to be negative for the infection. Additionally, it highlights the diagnostic limitations of screening tests to rule out diseases in animals intended to be used in preclinical studies. 相似文献
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Borland Hayden P. Gilby Ben L. Henderson Christopher J. Connolly Rod M. Gorissen Bob Ortodossi Nicholas L. Rummell Ashley J. Pittman Simon J. Sheaves Marcus Olds Andrew D. 《Landscape Ecology》2022,37(5):1385-1400
Landscape Ecology - Landscape modification alters the condition of ecosystems and the structure of terrain, with widespread impacts on biodiversity and ecosystem functioning. Seafloor dredging... 相似文献
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Newly-sown S24 perennial ryegrass at Hurley and old established ryegrass-dominant mixed pasture at Rothamsted were treated with several pesticides, singly and in combination, over the period 1969–73. Yields were either unaffected or increased by up to 30% in any one year, depending on the treatment, the newly-sown sward giving the more consistent response from year to year. 相似文献
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