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91.
Medical records and histologic sections of 40 cats with acute pancreatitis were reviewed. Two distinct groups of cats with pancreatitis were established by histologic analysis of tissue. Group I (32 cats) had acute pancreatic necrosis (APN). Group 2 (8 cats) had suppurative pancreatitis. Ages of affected cats ranged from 3 weeks to 16 years. l h e majority consisted of indoor cats of the Domestic Short-Haired breed but Siamese cats were over-represented relative to the general population ( P > 0.05). Twenty-two percent of cats were obese and 57%were underweight. Thirty-eight percent of cats had acute disease. In the other cats, two stages in the progression of the disease were evident: (1) anorexia. weight loss, and lethargy, followed by (2) acute deterioration, development of shock, and a moribund state, despite fluid therapy. The most common clinical signs were severe lethargy (100%), reduced appetite (97%), dehydration (92%), and hypothermia (68%). The initial hemogram occasionally showed a neutrophilia (30%) and anemia (2670)but packed cell volume (PCV) decreased markedly to the extent that 555% of cats were anemic terminally. Serum biochemical abnormalities included increased activities of A1, T (68%) and ALP (50%). and increased conrentrations of bilirubin (64%) and cholesterol (64%).Cats with APN were hyperglycemic (64%)), glycosuric (60%) and ketonuric (20%), whereas cats with suppurative pancreatitis tended to be hypoglycemic (7%). Renal failure and electrolyte abnormalities were mild or infrequent escept for hypokalemia (56%)).This study characterizes a severe necrotizing pancreatitis in the cat similar to that reported in other species, and a histologically distinct suppurative pancreatitis.  相似文献   
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The influence of melatonin administration to sperm donors on the freezability of ram semen and enzyme leakage through sperm cells during different steps of the cryopreservation process were evaluated in the breeding and non-breeding season. Melatonin implantation to rams in the breeding season improved post-thaw sperm viability and intact acrosome rates without influencing the motility rate (p   < 0.05). Likewise, the post-thaw alkaline phosphatase release through sperm cells was significantly lower in the melatonin-treated group in comparison with untreated controls (p   < 0.05). In the non-breeding season, melatonin administration enhanced intact acrosome rates (p   < 0.05) and reduced aspartate aminotransferase activity (p   < 0.05) post-thaw in the offseason ejaculates. Melatonin implantation twice in the breeding and non-breeding season did not produce any further improvement in the post-thaw sperm parameters in the non-breeding season ejaculates. It was concluded that melatonin administration to sperm donors improved freezability of ram semen collected from these rams and reduced enzyme leakage through sperm cells during cryopreservation.  相似文献   
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Bovine viral diarrhoea virus (BVDV) is an economically significant disease affecting the Australian cattle industry, with losses stemming from decreased production and reproductive performance and control costs. However, these losses can be difficult to appreciate, particularly in endemic regions. Overall, there is a variable but high herd-level seroprevalence in Australia. Despite a potentially high financial burden of the disease, the onus for control ultimately falls on producers and strategies employed will vary between regions. A cross-sectional study, using a postal survey, was conducted in 2013 to evaluate the BVDV knowledge, attitudes and management practices utilised by Australian cattle producers. A total of 192 producers participated in the study, and results indicate that knowledge and attitudes towards disease risk are variable and can be improved. Producer knowledge of how persistently infected (PI) animals are produced was higher than that of disease outcomes or transmission pathways. Implementation of biosecurity practices was limited, with approximately half of respondents employing quarantine procedures for introduced stock and only 2% indicating they would antigen test introduced stock for BVDV. Approximately a third (36%) of producers reported engaging in BVDV control, with the majority of these using vaccination strategies over deliberate exposure to a PI. Knowledge of and engagement with BVDV control was positively influenced by the producer relationships with veterinarians. Findings from this study suggest that building on education and delivering a consistent message among stakeholders would likely improve producer awareness and understanding in relation to BVDV and support decision making in BVDV management.  相似文献   
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delta-Oximinolevulinic acid competitively inhibits delta-aminolevulinic acid dehydrase at low concentrations.  相似文献   
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Conventional water-soluble iodine-containing contrast media such as salts of diatrizoic and iothalamic acids dissociate in solution resulting in preparations which are very high in osmolality. Intravascular or intrathecal injections of these compounds therefore represent severe physicochemical insult to the body, with many associated side effects. Contrast media with lower osmolalities have been produced in two ways: first by producing compounds which do not dissociate in solution (metrizamide, and more recently iopamidol and iohexol), and second by creating dimers (ioxaglate). These media provide significant clinical advantages over the conventional, hyperosmolar media. A new class of nonionizing dimers with even lower osmolalities are currently being investigated. This paper reviews the development of the low osmolar media, their advantages, and their use in medical and veterinary radiology.  相似文献   
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