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排序方式: 共有261条查询结果,搜索用时 15 毫秒
91.
David S. Biller DVM Beth P. Partington DVM MS Takayoshi Miyabayashi BVS MS Renee Leveille DVM 《Veterinary radiology & ultrasound》1994,35(1):30-33
Chronic hypertrophic pyloric gastropathy was diagnosed using ultrasound in six dogs that were presented for chronic vomiting. An evenly thick hypoechoic layer surrounding the pyloric lumen was visualized ultrasonographically in dogs with grades 1 or 2 chronic hypertrophic pyloric gastropathy. This was histologically found to correspond with a thickened muscular layer. Gastric wall thickness was greater than or equal to 9 mm in all six dogs. In dogs with grade 1 or 2 chronic hypertrophic pyloric gastropathy, the hypoechoic muscular layer was greater than or equal to 4 mm. 相似文献
92.
Valentine BA Cebra CK Taylor GH 《Journal of the American Veterinary Medical Association》2007,231(7):1098-1103
OBJECTIVE: To evaluate signalment, history, clinical and pathologic findings, and seasonal weather patterns in association with fatal gastrointestinal parasitism in goats. DESIGN: Retrospective case series. ANIMALS: 152 goats that were > 1 day of age. PROCEDURES: Characteristics including age and counts of coccidia oocysts and trichostrongyle ova (eggs) per gram of feces (EPG) in goats that died because of gastrointestinal parasitism and goats that died because of other causes were compared. Weather data and annual incidence of caprine fatal gastrointestinal parasitism were investigated. RESULTS: Death was attributed to gastrointestinal parasitism in 31 of 152 (20%) goats (median age, 5 months; range, 1 month to 7 years); deaths were attributed to coccidiosis (n = 7 goats; median age, 4 months; median EPG, 2,225), trichostrongylosis (6 goats; median age, 1.25 years; median EPG, 3,700), or dual infection (18 goats; median age, 6.7 months; median EPG, 8,088 coccidia and 5,475 trichostrongyles). Sudden onset of weakness or death was a common historical finding; diarrhea was evident in 15 goats. Common postmortem findings in these goats included cachexia, tissue pallor, poorly formed feces, and mesenteric lymphadenomegaly. Wet weather in spring and summer was associated with increased annual incidence of fatal gastrointestinal parasitism in goats. CONCLUSIONS AND CLINICAL RELEVANCE: Gastrointestinal parasitism is an important cause of death in goats. Clinical signs may not develop until just prior to death, and diagnosis is achieved via parasitologic evaluation of feces and necropsy. Seasonal weather patterns should be considered on an annual basis when designing parasite control programs for goats. 相似文献
93.
Brainard BM Meredith CP Callan MB Budsberg SC Shofer FS Driessen B Otto CM 《American journal of veterinary research》2007,68(3):251-257
OBJECTIVE: To determine the effects of nonsteroidal anti-inflammatory drugs of various cyclooxygenase selectivities on hemostasis and prostaglandin expression in dogs. ANIMALS: 8 client-owned dogs with clinical signs of osteoarthritis. PROCEDURES: Dogs received aspirin (5 mg/kg, PO, q 12 h), carprofen (4 mg/kg, PO, q 24 h), deracoxib (2 mg/kg, PO, q 24 h), and meloxicam (0.1 mg/kg, PO, q 24 h) for 10 days each, with an interval of at least 14 days between treatments. On days 0 and 10, blood was collected for platelet aggregation assays, thrombelastography, and measurement of lipopolysaccharide-stimulated prostaglandin E(2), platelet thromboxane B(2) (TXB(2)), and free serum TXB(2) and 6-keto-prostaglandin F (PGF)-1alpha concentrations. RESULTS: Platelet aggregation decreased after treatment with aspirin and carprofen, whereas significant changes from baseline were not detected for the other drugs tested. Thrombelastograms obtained after treatment with carprofen revealed decreased maximum amplitude and alpha-angle, suggesting hypocoagulability. Maximum amplitude and coagulation index increased after treatment with deracoxib. Plasma concentrations of prostaglandin E(2) decreased after treatment with carprofen or deracoxib, and platelet TXB(2) production increased after treatment with aspirin. Serum concentrations of the prostacyclin metabolite 6-keto-PGF-1alpha did not change significantly after treatment with any of the drugs, although the ratio of free TXB(2) to 6-keto-PGF-1alpha decreased slightly after treatment with carprofen and increased slightly after treatment with deracoxib. CONCLUSIONS AND CLINICAL RELEVANCE: At the dosages tested, treatment with meloxicam affected platelet function minimally in dogs with osteoarthritis. Treatment with carprofen decreased clot strength and platelet aggregation. Clot strength was increased after treatment with deracoxib. 相似文献
94.
95.
Georgette E. Shields Mary Beth Whitcomb Betsy Vaughan Erik R. Wisner 《Veterinary radiology & ultrasound》2015,56(5):466-473
Injuries involving the femoral third trochanter are an uncommon but important source of equine lameness; however, clinical localization can be challenging. The purpose of this retrospective study was to describe ultrasonographic and scintigraphic findings in a group of horses with presumed third trochanter injury. Medical records of an equine referral hospital were searched from 2004–2014, and 20 horses met the inclusion criteria. Lesions consistent with third trochanter fracture were identified with ultrasound in 14/20 horses. Onset of lameness was acute (11), insidious (2), or unknown (1). All but one horse was lame at presentation, ranging from Grade 2–4/5. Ultrasound was the primary diagnostic modality in 5/14 horses with fragmentation, while scintigraphic findings of intense (3), moderate (5), and mild (1) increased radiopharmaceutical uptake (IRU) prompted ultrasonographic examinations in 9/14 fractured horses. A nondisplaced fracture was suspected in an additional horse with intense IRU and negative ultrasound findings. In the remaining five horses, imaging findings included only mild IRU. Lameness was localized to other regions in these cases. Six of 12 fractured horses with available outcome data were returned to function after a prolonged rehabilitation of 8–18 months. Scintigraphic findings helped to direct focused ultrasound exams in the majority of fracture cases. Horses with evidence of third trochanter fracture had similar clinical characteristics to that reported for pelvic fractures and authors therefore recommend ultrasonographic examination of both regions, especially when scintigraphy is unavailable. Prognosis for return to function in horses of the current study was less favorable than previously reported. 相似文献
96.
Ordinary Least Squares Regression of Ordered Categorical Data: Inferential Implications for Practice
Beth Larrabee H. Morgan Scott Nora M. Bello 《Journal of Agricultural, Biological & Environmental Statistics》2014,19(3):373-386
Ordered categorical variables are frequently encountered as response variables in many disciplines. Agricultural examples include quality assessments of soil or food products, and evaluation of lesion severity, such as teat ends status in dairy cattle. Ordered categorical responses (OCR) are characterized by multiple levels recorded on a ranked scale, whereby levels appraise order but may not be informative of relative magnitude or proportionality between levels. A number of statistically sound methods are available in the standard toolbox to deal with OCR, such as constrained cumulative logit and probit models; however, these are commonly underutilized in practice. Instead, ordinary least squares linear regression (OLSLR) is often employed to infer upon OCR, despite violation of basic model assumptions. In this study, we investigate the inferential implications of OLSLR-based inference on OCR using simulated data to explore realized Type I error rate and realized statistical power under a variety of scenarios. The design of the simulation study was motivated by a data application, thus considering increasing number of levels and various frequency distributions of the OCR. We then illustrate inferential performance of OLSLR relative to a probit regression model fitted to an OCR using a survey dataset of veterinarian antimicrobial use in cattle feedlots. This article has supplementary material online. 相似文献
97.
An Allee effect occurs when at low densities there is a positive relationship between density and fitness leading to a higher probability of extinction. One circumstance in which it may arise is when isolated individuals are less effective in modifying their environment in a favourable way than groups of individuals. In this paper we use Porcellio scaber to test the hypothesis that the fitness correlate of growth rate will vary as a function of density not just due to the negative effects of increasing interference competition whilst foraging at higher densities, but also positively at lower densities due to isolated individuals spending more time and energy searching for other individuals with which to aggregate whilst sheltering.Below densities of 70 m–2 relative growth rates increased as a function of density, above 70 m–2 growth rate decreased with increasing density. Time spent walking and searching increased at lower densities. These behavioural observations, together with the original observations on water loss and oxygen consumption made by Allee [1], are used to interpret the curvilinear growth rate response to density as an example of a component Allee effect, which is discussed in relation to the importance of aggregation as an adaptation to the terrestrial environment in the Oniscidea. 相似文献
98.
Renae J. Watson Allison V. Level Beth Oehlerts 《Journal Of Agricultural & Food Information》2013,14(3):206-219
Colorado State University Libraries (CSUL) support the preservation of agricultural history, as evidenced by their participation in the Preserving the History of United States Agriculture and Rural Life: State and Local Literature, 1820–1945 project, administered by Cornell University. This article reviews CSUL’s work on this preservation project, including digitization of historical agriculture-related documents. CSUL’s latest effort to keep agricultural literature relevant and accessible includes moving the Colorado Agriculture Bibliography website to Springshare’s LibGuides platform (https://libguides.colostate.edu/agbib). Advantages and challenges of using the LibGuides platform for the promotion and sharing of such collections are discussed. 相似文献
99.
Mary Beth Stanton DVM John V. Steiner DVM Dipl ACT D. G. Pugh DVM MS Dipl ACT ACVN 《Journal of Equine Veterinary Science》2004,24(1):14-19
Endometrial cysts are a contributing factor to subfertility in the mare. This article is a review of incidence, pathogenesis, clinical significance, diagnostics, and current treatments available. 相似文献