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Second-year veterinary students were surveyed at the beginning and end of a 15-week semester regarding their confidence in performing three clinical reasoning skills: (1) making Problem Lists; (2) making Rule-Out Lists; and (3) selecting appropriate diagnostic tests. Each week during the semester, these skills were practiced in small-group case discussions. Changes in self-confidence were analyzed and studied in light of faculty assessments of student competence in performance of the three skills. RATIONALE: The purpose of the study was to determine if students' self-confidence in performing three clinical reasoning skills increased with practice. METHODOLOGY: On the first and last days of class, students rated their confidence in each of the three skills on a scale of 0 to 10. Mean confidence scores for the whole class both for time points and for each of the three skills were analyzed. RESULTS: There were significant increases in students' self-confidence in all three clinical reasoning skills over the semester each year. A greater percentage of students expressed improved confidence in selecting appropriate diagnostic tests than in the other two skills in three of the four years studied. CONCLUSIONS: Students' self-confidence in performing three clinical reasoning skills improved over the course of a semester in which they practiced the skills in a CBL format. Subjective faculty assessment of students' competence in these skills generally indicated improvement. However, no meaningful conclusions about the correlation of skill competence and student confidence could be drawn because of inadequacies in the measurement of student performance.  相似文献   
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THE FIRST TWENTY-ONE YEARS OF VETERINARY DIAGNOSTIC ULTRASOUND   总被引:2,自引:0,他引:2  
The veterinary literature of 1966–1986 was searched for articles and books related to the use of diagnostic ultrasound in animals. There were 492 references, categorized as follows: general, 30; small animal applications, 169; large animal applications, 248; blood pressure measurement, 23; ultrasound-guided biopsy, 4; miscellaneous, 18.  相似文献   
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A 21-yr-old male North American river otter (Lontra canadensis) with a chronic history of degenerative osteoarthritis was evaluated for acute posterior paralysis. Because no definitive cause was identified and a poor prognosis was expected, the otter was euthanatized. A malignant neoplasm of adrenal gland origin with disseminated metastases to the central nervous system, lymph nodes, diaphragm, pancreas, spleen, and liver was diagnosed on postmortem examination. No clinical signs of disseminated neoplasia had been noted throughout the otter's history. The adrenal neoplasm was composed of nests of epithelial cells surrounded by a fine fibrovascular stroma. Neoplastic cells were immunohistochemically positive for chromogranin A, PGP9.5, metencephalin, and endorphin and negative for melan A and inhibin, confirming a diagnosis of a malignant pheochromocytoma. On the basis of the necropsy finding, metastasis of the pheochromocytoma might have contributed to the observed clinical signs.  相似文献   
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The dog is widely used as a translational experimental model studying the host response and new treatments for human endotoxemia. The present study evaluated the applicability of a novel patient-near neutrophil chemiluminescence assay for the measurement of endotoxin activity in human blood when applied to canine blood samples. The assay was observed to be analytically sensitive and specific to endotoxin when tested in vitro, spiked with purified Escherichia coli lipopolysaccharide and live E. coli. The diagnostic sensitivity was sustained during Gram-positive contamination. Finally, it also demonstrated diagnostic potential when able to discriminate dogs with spontaneously occurring endotoxemia from both healthy dogs and diseased dogs without endotoxemia. The rapid patient-near assessment of endotoxin activity in canine blood should facilitate future studies on endotoxemia in both spontaneous disease and in experimental settings.  相似文献   
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Several studies have evaluated the spatial distribution of cool- and warm-season grasses across different topographic positions in the Nebraska Sandhills, but limited research has explored topographic differences in total plant production or production of plant functional groups in relation to variable amounts of precipitation. This study evaluated how spring and growing season precipitation influenced plant production at four topographic positions common in the eastern Nebraska Sandhills. Plant production data were collected from annually moved grazing exclosures in mid-June (peak cool-season grass production) and mid-August (peak warm-season grass production) during a 17-yr period from 2001 to 2017. Total plant production and precipitation use efficiency were 35 ? 58% greater on interdune positions, and precipitation marginal response for total plant production was more sensitive to increases in spring and growing season precipitation on interdune compared with dune positions in both mid-June and mid-August. The greater precipitation marginal response of total plant production on interdune positions was driven primarily by greater increases in cool-season grass production with increasing spring or growing season precipitation. Warm-season grass precipitation marginal response was not different among the topographic positions, but production was 23 ? 70% greater on interdune compared with dune topographic positions in mid-August. When differences in the amount of each topographic position at the study location were accounted for, growing season precipitation explained 49% of the variation for total plant production in mid-August, but spring precipitation only explained 23% of the variation for total plant production in mid-June. Because of the differential response of plant production at dune and interdune positions, incorporating the relative amount of each topographic position into estimates of plant production at the pasture or ranch scale will provide better information for adjusting stocking rates to more accurately match animal demand with forage availability.  相似文献   
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内部的挑战和机遇 生产和均一性 挖掘遗传的潜力,也就是繁殖性能或生长的潜力,对于动物养殖业来说是一个连续的挑战。营养通常不是限制的因素。然而,营养学家和养殖者承担这一挑战。为了最大程度地发挥动物的生产性能的潜力,高精确度的分析技术,包括DNA排列顺序,使我们能够充分了解和分析胃肠  相似文献   
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Sparkes A  Wray J  Leece E  de Risio L  Murphy S  Furneaux R  Sansom J  Coatesworth J 《The Veterinary record》2007,161(24):826; discussion 826-826; discussion 827
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