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91.
The records of 23 dogs and cats diagnosed with spontaneous gastroduodenal perforation (GDP) were retrospectively reviewed. Survival was 63% in dogs and 14% in cats. Rottweilers <5 years of age were overrepresented. Clinical evidence of gastrointestinal bleeding was common in dogs but not in cats. Shock was an uncommon presenting condition in dogs and was not closely linked to outcome. In fact, progression of an ulcerating lesion to GDP was not associated with marked changes in symptoms exhibited by many patients in this study. Most GDPs were associated with histopathological evidence of subacute or chronic peritoneal reaction at the time of diagnosis. This suggests that diagnostic methods employed lacked sensitivity in identifying early perforating lesions, and that dramatic signs of acute abdomen following gastroduodenal perforation may not be as common as was previously thought.  相似文献   
92.
Fifty canine fecal samples were evaluated by five flotation procedures to compare the sensitivity of the zinc sulfate (ZnSO4) centrifugation flotation test with ZnSO4 flotation tests using benchtop incubation during the flotation period. One or more parasite species were detected in 40 samples. Results showed that centrifugation with ZnSO4 solution was significantly more likely to detect a positive sample than benchtop procedures. The difference in procedures was due primarily to increased detection of Trichuris eggs and Giardia cysts by centrifugal flotation. No significant difference was seen in the ability of benchtop procedures to detect positive samples when tests sat either for 5 or 10 minutes before examination.  相似文献   
93.
Matrix metalloproteinases (MMPs) are enzymes that play key roles in angiogenesis, tumor invasion, and metastasis in a wide variety of species. The purpose of this study was to evaluate pro and active MMP 2 and 9 concentrations in tumor, normal stromal tissue, and serum from tumor-bearing cats. We hypothesized that serum concentrations of pro and active forms of MMPs 2 and 9 would be predictive of MMP concentrations in tumor tissue and that these MMP concentrations would correlate with the histopathologic grade of the malignancies. Pro and active forms of MMPs 2 and 9 were determined by gelatin zymography and subsequent computerized densitometry from tumor and nearby stromal tissue and serum from 49 cats with various malignancies. The serum concentrations of MMPs from these tumor-bearing cats were compared with serum concentrations of MMPs from 44 normal cats of similar age and gender. Measurable concentrations of MMPs 2 and 9 were found within tumor, stromal, and serum samples. Mean concentrations of total pro and active MMPs 2 and 9 within tumor tissue were significantly higher (P values <.0001, .0031, <.001, and .0064, respectively) when compared with stromal tissue from the same animals. Serum MMP concentrations from tumor-bearing cats were higher than those from normal cats. Poor correlation was found between serum MMP concentrations and tissue MMP concentrations of increasing histologic grades of malignancies.  相似文献   
94.
A 22-year-old pinto mixed breed mare was admitted for evaluation of severe colic signs and gastric reflux. Multiple nonpainful, variably sized hard masses were palpated in the subcutis over the thorax, abdomen, and hindquarters of the horse. The mare was diagnosed with sterile peritonitis and had systemically high gamma-glutamyltransferase, amylase, and lipase. Three days into treatment she became febrile with signs of persistent and mild abdominal discomfort; euthanasia was elected. Necropsy revealed peripancreatitis, pancreatic fibrosis, abdominal steatitis and panniculitis. Panniculitis associated with peripancreatitis has been described in humans and dogs but not in horses. Pathogenic models for this entity are discussed.  相似文献   
95.
To reduce the cost of whole herd screening for bovine viral diarrhea virus persistently infected animals, the sensitivity and specificity of an antigen-capture enzyme-linked immunosorbent assay (AC-ELISA) and a microtiter virus isolation ELISA using saline from ear notch samples or pooled serum was determined. Pooled saline from ear notch samples, assayed by AC-ELISA, gave a sensitivity and specificity of 98% and 94%, respectively, for pools containing 2 samples and 72% and 100%, respectively, for pools of 5. The sensitivity of pooled ear notch or serum samples for bovine viral diarrhea virus detection by microtiter virus isolation (sensitivity < 5%) or serum samples for detection by AC-ELISA (sensitivity < 15%) is too low to be used for whole herd screening. Pooling saline from ear notch samples from 2 animals tested by AC-ELISA, however, could provide a less expensive, reliable method for whole herd screening for bovine viral diarrhea virus.  相似文献   
96.
Parasite surveys of free-ranging wildlife provide important information for monitoring population health. Between March 2001 and March 2003, we sampled 10 ocelots (Leopardus pardalis), eight Geoffroy's cats (Oncifelis geoffroyi), a jaguarundi (Herpailurus yaguarondi), five pampas foxes (Pseudalopex gymnocercus), and three crab-eating foxes (Cerdocyon thous) at three sites in the Bolivian Chaco. The objective of the study was to survey the parasite fauna of these carnivores and compare prevalence of parasites among the sites. The parasite community of these carnivores was diverse, with representatives from eight genera of nematodes, two families of cestodes, two protozoan species, and six arthropod species. Fecal parasites identified from 12 of the 13 felids and five of the six canids examined included Aelurostrongylus abstrusus, Ancylostoma tubaeforme, Uncinaria sp., Crenosoma sp., Toxocara cati, Spirurida, Capillaria aerophila, Spirometra sp., Taeniidae, and Cystoisospora sp. Four tick species, Amblyomma parvum, A. tigrinum, A. ovale, and A. cajennense, and two flea species, Pulex irritans and Delostichus phyllotis, were identified. Two crab-eating foxes had serologic evidence of heartworm disease (HWD). Antibodies against Toxoplasma gondii were found in 15 of 26 animals. Although HWD was found only in canids inside the national park, parasite prevalence did not appear to differ among sites, and no evidence was found of parasite spillover from domestic to wild carnivores.  相似文献   
97.
Management of prion diseases in livestock would benefit greatly from availability of a validated blood test. A promising immunocapillary electrophoresis technique (also known as capillary electrophoresis fluoroimmunoassay) to detect abnormal prion protein in blood from live sheep is evaluated here. Capillary electrophoresis fluoroimmunoassay was applied to analysis of extracted blood from scrapie-exposed sheep (n = 87; 347 samples) at various stages of incubation, and to control sheep (n = 194; 489 samples). Overall, test values for the control and test populations were not significantly different, and a similar proportion of control (7%) and test (10%) sheep were classified as positive. Over 2-3 month intervals from birth until clinical disease, test specificity and sensitivity ranged from 66.7% to 100% and 0% to 66.7%, respectively, indicating poor diagnostic performance at all stages of pathogenesis. In routine application, in its present form, the capillary electrophoresis fluoroimmunoassay procedure proved to be insufficiently robust for use as a blood test for scrapie diagnosis.  相似文献   
98.
超高压杀菌技术在乳品中的应用   总被引:3,自引:0,他引:3  
超高压杀菌技术在食品加工中的商业应用已经有20多年的历史,而第一次在乳品中应用的实验可追溯至1899年.该项技术和其它的杀菌方法一样,通常用于杀死食品中的致病菌和腐败菌.恒天然公司经过多年的研究改进了该技术,在杀死大部分或全部有害微生物的同时,使食品中的营养成分成功地得以保留下来,以此创造崭新的功能性产品.  相似文献   
99.
Resistance of Brassica napus (oilseed rape, canola) conferred by three different major resistance genes has been overcome by changes in virulence of Leptosphaeria maculans populations in France and Australia. In South Australia where B. napus cultivars with major gene resistance derived from Brassica rapa ssp. sylvestris were grown extensively, resistance was rendered ineffective within 3 years of commercial release of the cultivar. Disease severity was higher on cultivars with sylvestris-derived resistance than cultivars with polygenic resistance. This Australian situation is compared to that in France, where resistance conferred by the Rlm1 gene was overcome nation-wide in 5 years under commercial cropping practices, and also where a source of resistance introgressed into B. napus from B. juncea was rendered inefficient in 3 years in experimental field plots near Rennes.  相似文献   
100.
Equine embryos can remain viable for 12 to 24 hours when cooled and stored at 5°C.1 Cryopreservation of embryos would allow for long-term preservation of genetic material and more efficient management of embryo recipients. This study compared pregnancy rates after transfer of equine embryos vitrified within 1 hour of collection or cooled for 12 to 19 hours before vitrification. Mares (N = 40) were superovulated using equine follicle-stimulating hormone (eFSH). Embryos were recovered 6.5 days after ovulation or 8 days after human chorionic gonadotropin. Forty morulae or early blastocysts with a grade of 1 to 2 and <300 mm in diameter were randomly assigned to 1 of 2 treatments: Group 1 (n = 20), washed 4 times in a commercial holding medium and then vitrified; Group 2 (n = 20), washed 3 times and then stored in the same holding medium at 5°C to 8°C in a passive cooling device for 12 to 19 hours before being vitrified. To thaw, embryos were warmed by holding the straw in air at room temperature for 10 seconds and then submerged in a water bath (20°C to 22°C) for an additional 10 seconds. The contents of the straw were transferred directly into a recipient that had ovulated 4 to 6 days previously. There were no differences (P > .05) in embryo diameter, grade, or morphology score between treatment groups before vitrification. Pregnancy rates (day 16) were not different (P > .05) between embryos vitrified immediately after collection (15 of 20; 75%) and embryos cooled for 12 to 19 hours before vitrification (13 of 20; 65%). Based on these results, small equine embryos (<300 mm) can be stored at 5°C to 8°C for 12 to 19 hours before vitrification without a significant loss of viability.  相似文献   
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