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Moore VA 《Science (New York, N.Y.)》1911,34(876):457-464
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Animals can learn to voluntarily control neuronal activity within various brain areas through operant conditioning, but the relevance of that control to cognitive functions is unknown. We found that rhesus monkeys can control the activity of neurons within the frontal eye field (FEF), an oculomotor area of the prefrontal cortex. However, operantly driven FEF activity was primarily associated with selective visual attention, and not oculomotor preparation. Attentional effects were untrained and were observed both behaviorally and neurophysiologically. Furthermore, selective attention correlated with voluntary, but not spontaneous, fluctuations in FEF activity. Our results reveal a specific association of voluntarily driven neuronal activity with "top-down" attention and suggest a basis for the use of neurofeedback training to treat disorders of attention. 相似文献
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Brandon C. Moore Wan-Nor Fitri Lauren Augustine 《Anatomia, histologia, embryologia》2020,49(3):390-401
As wild population threats for the endangered false gharial (Tomistoma schlegelii) persist, conservation breeding programs, including developing semen collection techniques for subsequent artificial insemination, are becoming important species conservation measures. Developing reproductive biology understanding of a species is important to developing best practices and hopefully maximizing reproductive successes. However, information on crocodylians functional copulatory anatomy in general is lacking. To that end, zoological facilities and conservation centres have the exceptional opportunity to contribute new understandings that may not otherwise be attainable regarding crocodylian reproductive anatomy, particularly during routine physical examinations or post-mortem necropsies. Therefore, to better understand T. schlegelii reproductive biology, to contribute knowledge in support of zoo breeding conservation efforts and to contribute to what is known overall about crocodylian reproduction, we investigated phallic anatomy of adult male Tomistoma from two zoological populations, the St. Louis Zoo, USA and Sungai Dusun Wildlife Reserve, Peninsular Malaysia. Here, we present the gross anatomical features and histological analysis of underlying tissue-level details in pursuit of a better understanding of copulatory function and associated gamete transfer mechanisms. While much of the overall Tomistoma phallic morphology and inferred function corresponds to that of other crocodylian species and speaks to conserved aspects of functional anatomy across taxa, species-specific aspects of glans and glans tip morphology are also identified. These novelties are discussed in a general function and overall broader evolutionary contexts. 相似文献
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Courtney E. Johnson Davis M. Seelig Frances M. Moore Tammy J. Ruska Daniel A. Heinrich 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2020,49(2):232-239
Two domestic shorthair cats were presented with anorexia and dehydration following ingestion of caramelized onions. Shared key findings from a CBC (ADVIA 2120), serum biochemistry, and urinalysis included a spurious, marked leukocytosis with discordant basophil (BASO) channel and peroxidase channel WBC counts, normal manual leukocyte counts, mild, non-regenerative anemia with discrepancies between automated and manual reticulocyte counts, an abundance of large Heinz bodies (HBs), and highly irregular scattergrams. Case 1 also demonstrated a markedly elevated mean corpuscular hemoglobin concentration (MCHC) and discrepancies between RBC hemoglobin indices. Spurious leukocyte results were confirmed through re-analysis of samples (including the acquisition of a new sample, use of an alternate analyzer (Sysmex XT-2000iV; Case 1 only), and evaluation of scattergrams and blood films (Cases 1 and 2). Repeatedly discrepant reticulocyte counts were also identified. In both cases, the erroneous BASO WBC counts, discrepancies in reticulocyte counts and RBC indices, and atypical scattergrams were interpreted to result from various effects of the HBs. These cases emphasize the importance of reviewing blood films, interpreting scattergrams, and the usefulness of duplicate methods for determining various measurands on hematology analyzers. 相似文献
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