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151.
The white blood picture was examined in 135 dogs with parvovirus disease during the course of the illness. 91 dogs survived, 44 died. The surviving dogs showed higher mean total leucocyte, neutrophil, and eosinophil counts whereas the mean lymphocyte, neutrophil, and monocyte counts on the first day of the disease were lower in those dogs which survived than in those ones which died later. Increasing lymphocyte and monocyte counts appear to be a favourable prognostic sign. The older the dogs, which fell ill, were, the more favourable the prognosis turned out.  相似文献   
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Three computerized multimedia programs on large and small animal veterinary orthopedic radiology were developed and implemented for the radiology curriculum as an alternative to traditional film-based laboratory learning. Programs utilized "hot words" (colored text words that displayed an overlaid image label that highlighted lesions) and interactive quizzes which responded appropriately to selected answers. "Hot words" helped students develop confidence in accurate lesion detection and the interactive quizzes transformed learning from a passive to an active process. Multiple examples were provided for reinforcement and concepts were incorporated from other clinical disciplines for curriculum integration. Programs were written using a presentation software program, Toolbook® for DOS based platform, and contained radiographic images made by laser-scanning digitization. Multiple students could simultaneously access the programs through a network server. These pilot programs were implemented successfully and computerized multimedia presentation proved to be well suited to teaching radiology. Development of the programs required attention to a number of hardware, software, time and cost factors.  相似文献   
154.
Dynamics of large wood in an eastern U.S. mountain stream   总被引:1,自引:0,他引:1  
Large wood (LW) is an important feature in many streams in northeastern North America, yet the dynamics (recruitment, movement, and export) of large wood remain largely undocumented for streams in this region. In this study we quantify the dynamics of LW in 400 m of a second-order, high gradient, boulder-dominated stream in the eastern Adirondack Mountains, NY. Characteristics and location of all LW (>1-m length, >10-cm diameter) in the 400-m study reach were initially recorded and pieces were individually tagged in November 2000. Subsequent surveys were conducted in late summer/fall of 2001, 2003, and 2004. Twenty-six% of the 112 pieces of LW initially tagged moved 5.0 m or more during the 4 years of this study. Mobile wood was, on average, shorter than non-mobile wood. Nearly all mobile wood was shorter than the 8.0-m bankfull width of the stream. From 2000 to 2004, 2.16 m3 (0.54 m3 100 m−1; 43 pieces) of LW entered the study reach and 0.7 m3 (0.18 m3 100 m−1; 13 pieces) left the stream. Retention of wood in debris dams was key to reducing potential export. For this stream, located within a second-growth mixed northern hardwood riparian forest that is approaching maturity, the net wood accumulation rate was estimated as ranging from 0.09 to 0.15 m3 100 m−1 year−1. Our data support previous observations that LW length strongly influences its potential to move in high gradient streams, though debris dams can reduce LW movement rates and movement distances for wood of all sizes.  相似文献   
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Intracranial neoplasia   总被引:1,自引:0,他引:1  
A diagnosis of intracranial neoplasia in companion animals may be made by computed tomography (CT) or magnetic resonance imaging (MRI). MRI is the better method for detecting and characterizing intracranial tumors because of its superior depiction of soft tissues and relative lack of degrading artifacts, intracranial tumors may be characterized by distinct features; a systematic evaluation of these features on CT or MRI images may help to identify specific tumor types. In this article, guidelines for formulating differential diagnoses based on these imaging criteria will be discussed. Technical recommendations and protocols for CT and MR imaging will also be provided.  相似文献   
157.
Reference values of serum phenols between 0.3 and 0.7 mmol/L in dogs respectively between 0.25 and 0.37 mmol/L in horses are determined. In dogs increased phenol values were found frequently in hepatopathy. Furthermore elevations, particularly in diseases of the gastrointestinal tract, were obtained; especially in hemorrhagic enteritis of dogs, associated with parvovirosis, and in mechanical ileus of the small intestine and the large intestine respectively in horses. In renal and endocrine diseases increased phenol values were seldom obtained.  相似文献   
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The diagnosis of canine hypothyroidism and its differentiation from euthyroid sick syndrome still is a major diagnostic challenge. In this study, ultrasonography was shown to be an effective tool for the investigation of thyroid gland diseases. Healthy control dogs (n = 87), dogs with euthyroid sick syndrome (n = 26), thyroglobulin autoantibody-positive (TgAA-positive, n = 30) hypothyroid dogs, and TgAA-negative (n = 23) hypothyroid dogs were examined by thyroid ultrasonography. Maximal cross sectional area (MCSA), thyroid volume, and echogenicity were measured. Statistical analysis identified highly significant (P < .001) differences between euthyroid and hypothyroid dogs both in thyroid volume and in MCSA, whereas no significant differences in thyroid size were detected between healthy euthyroid dogs and dogs with euthyroid sick syndrome. In euthyroid and euthyroid sick dogs, parenchymal echotexture was homogeneous and hyperechoic, whereas relative thyroid echogenicity of both TgAA-positive and TgAA-negative hypothyroid dogs was significantly lower (P < .001). When using arbitrarily chosen cutoff values for relative thyroid volume, MCSA, and echogenicity, thyroid volume especially was found to have highly specific predictive value for canine hypothyroidism. In summary, the data reveal that thyroid sonography is an effective ancillary diagnostic tool to differentiate between canine hypothyroidism and euthyroid sick syndrome.  相似文献   
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