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661.
Virtual microscopy (VM) uses a computer to view digitized slides and is comparable to using a microscope to view glass slides. This technology has been assessed in human medical education for teaching histology and histopathology, but, to the authors' knowledge, no one has evaluated its use in teaching cytopathology in veterinary medical education. We hypothesize that students will respond positively to the use of VM for viewing cytopathology preparations and that the technology can be successfully used for student assessment. To test this hypothesis, we surveyed students regarding their level of satisfaction with features of the VM system, their preference for use of VM in the curriculum, and the potential influence virtual slides may have on student study habits; student performance on a traditional cytopathology practical examination and a similar exam using VM was evaluated. Our results show that student perception of the VM system is generally very positive, with some concerns about resolution and the need for continued exposure to traditional microscopy. Within the curriculum, students indicated a preference for the option of using virtual slides for studying and take-home exercises. Overwhelmingly, students wanted either hybrid laboratory sessions or sessions using glass slides with virtual slides available for study and review. Students identified many VM test-taking features as advantageous compared with traditional glass-slide practical exams as traditionally administered. However, students indicated a strong preference for continued use of traditional microscopy for graded practical exams. Students may be more likely to study slides in preparation for practical examinations if virtual slides are available. Results also indicate that VM can be used successfully for assessment purposes, but students should receive training in using virtual slides if the technology will be used for assessment.  相似文献   
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The aim of this study was to determine the prevalence and risk factors for Mycoplasma haemofelis (Mhf) and 'Candidatus Mycoplasma haemominutum' (Mhm) infections in domestic cats tested for feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) with a commercial enzyme-linked immunosorbent assay (ELISA) kit. Based on serological testing, cats were grouped as i) FIV-positive (n=25); ii) FeLV-positive (n=39); iii) FIV/FeLV-positive (n=8); and iv) FIV/FeLV-negative (n=77). Complete blood counts were followed by DNA extraction, species-specific polymerase chain reaction (16S rRNA gene) for Mhf and Mhm and Southern blotting for all animals. Mhf DNA was found in 4.0, 2.6, 12.5 and 7.8% of the cats from groups i, ii, iii and iv, respectively, while 32, 5.1, 50 and 5.2% of these animals had an Mhm infection. Cats with FIV (OR=4.25, P=0.009) and both FIV and FeLV (OR=7.56, P=0.014) were at greater risk of being hemoplasma infected than retroviral-negative cats, mainly due to Mhm infection (OR=8.59, P=0.001 and OR=18.25, P=0.001, respectively). Among pure-breed cats, FIV-positive status was associated with hemoplasma infection (OR 45.0, P=0.001).  相似文献   
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Beef carcasses (n = 5,542) were evaluated by three USDA on-line graders and compared with the computed expert USDA quality (QG) and yield grades (YG) during 8-h shifts at a major beef-processing facility for a 2-wk period to evaluate the accuracy of applying USDA QG and YG within the traditional five-grade and the proposed seven-grade (segregating YG 2 and 3 into YG 2A, 2B, 3A, and 3B) YG systems. Quality grade distribution of the carcasses was 1.1% Prime, 50.0% Choice, 43.8% Select, and 5.1% No-Roll. Accuracy of applying QG was not affected (P>.05) by changing from the five-grade (91.5%) to either the seven-grade system, when determining only QG (94.3%), or the seven-grade system, when determining QG and YG (95.0%). Calculated expert YG successfully segregated carcasses into their respective YG, but on-line graders could not differentiate between YG 4 and 5 in the seven-grade systems. The application of YG in the five-grade system was more accurate (P<.05) than either of the seven-grade systems. A trend existed for on-line graders to undergrade carcasses as the numerical YG increased. Total accuracy of applying YG decreased by 19.4 to 21.8% when switching from the five-grade to the seven-grade system. The segmentation of USDA YG 2 and 3 into YG 2A, 2B, 3A, and 3B resulted in a decrease in the ability of on-line graders to accurately apply the YG.  相似文献   
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