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951.
952.
OBJECTIVE: To determine the prevalence of biofilm formation under long-term cell culture conditions in serum samples of dairy cattle, goats, cats, and dogs, and to determine whether there is an association between nanobacteria and biofilm formation. SAMPLE POPULATION: Serum samples of clinically normal animals (313 dairy cattle, 48 goats, 140 dogs, and 44 cats) and animals with various medical conditions (60 dogs and 116 cats). PROCEDURE: Serum was incubated under cell culture conditions and observed for biofilm formation by use of light microscopy, electron microscopy, and spectroscopy. A polymerase chain reaction assay was developed to identify 16S rRNA gene sequences of nanobacteria. RESULTS: Biofilm formation developed in serum samples of 304 of 313 (97%) cattle, 44 of 48 (92%) goats, 44 of 44 (100%) cats, and 126 of 140 (90%) dogs. Prevalence of serum samples with positive results for biofilm formation was not significantly different between cats or dogs with and without medical conditions associated with pathologic extraskeletal calcification processes. Scanning electron microscopy and spectroscopy of biofilm samples revealed small coccoid particles consisting mainly of calcium and phosphate. Polymerase chain reaction assay failed to amplify sequences of nanobacteria. CONCLUSIONS AND CLINICAL RELEVANCE: Under long-term cell culture conditions, biofilm made up of aggregates of calcium and phosphate crystals does form in serum samples of clinically normal dairy cattle, goats, cats, and dogs. Disease, however, does not predispose to biofilm formation in serum samples of dogs and cats. Our findings did not support the existence of nanobacteria in serum samples of cattle, goats, cats, and dogs.  相似文献   
953.
OBJECTIVE: To determine maximum extrarenal plasma clearance of technetium-99m-mercaptoacetyltriglycine (99mTc-MAG3) and maximum extrarenal hepatic uptake of 99mTc-MAG3 in cats. ANIMALS: 6 clinically normal adult cats. PROCEDURES: Simultaneously, baseline plasma clearance and camera-based uptake of 99mTc-MAG3 were determined in anesthetized cats. Double exponential curves were fitted to plasma clearance data. Injected dose was divided by area under the curve and body weight to determine 99mTc-MAG3 clearance. Regions of interest were drawn around kidneys and liver, and percentage dose uptake was determined 1 to 3 minutes after injection. After bilateral nephrectomy, simultaneous extrarenal plasma clearance and camera-based hepatic uptake of 99mTc-MAG3 were evaluated in each cat. RESULTS: Mean +/- SD baseline plasma clearance and extrarenal clearance were 5.29 +/- 0.77 and 0.84 +/- 0.47 mL/min/kg, respectively. Mean extrarenal clearance (as a percentage of baseline plasma clearance) was 16.06 +/- 7.64%. For right, left, and both kidneys, mean percentage dose uptake was 9.42 +/- 2.58, 9.37 +/- 0.86, and 18.79 +/- 2.47%, respectively. Mean hepatic percentage dose uptake before and after nephrectomy was 12.95 +/- 0.93 and 21.47 +/- 2.00%, respectively. Mean percentage change of hepatic uptake after nephrectomy was 166.89 +/- 23.19%. CONCLUSIONS AND CLINICAL RELEVANCE: In cats, extrarenal clearance of 99mTc-MAG3 is higher than that of other species; therefore, 99mTc-MAG3 is not useful for estimation of renal function in felids. Evaluation of renal function in cats may be more accurate via camera-based versus plasma clearance-based methods because camera-based studies can discriminate specific organs.  相似文献   
954.
A 13-year-old Morgan gelding was evaluated because of a mass in the caudal region of the abdomen. The horse had been presumed to be a gelding, but necropsy findings revealed a retained testis in the right retroperitoneal space. Histologically, the retained testis contained neoplastic cells; metastases were identified in the liver, spleen, lungs, and sublumbar lymph nodes. Immunohistochemical examination of the testis and metastatic tissues confirmed the diagnosis of malignant Sertoli cell tumor. Testicular neoplasms are infrequently reported in stallions. Seminomas are most commonly reported, whereas Sertoli cell tumors are considered to be rare. Typical biological behavior of Sertoli cell tumors in horses is unknown. To the authors' knowledge, there have been 2 reports of Sertoli cell tumors in horses; the tumors developed in descended testes, and 1 tumor was malignant.  相似文献   
955.
OBJECTIVE: To evaluate the veterinary version of the bladder tumor antigen (V-BTA) test as a screening test for transitional cell carcinoma (TCC) of the lower urinary tract of dogs. ANIMALS: 229 client-owned dogs. PROCEDURE: Urine samples from dogs were shipped overnight to a single laboratory to facilitate testing within 48 hours of collection by use of the V-BTA rapid latex agglutination urine dipstick test. Groups of dogs included the following: 1) dogs with TCC of the lower urinary tract, 2) healthy control dogs, 3) unhealthy control dogs with non-TCC urinary tract disease, and 4) unhealthy control dogs without urinary tract disease. Test sensitivity and specificity were calculated by use of standard methods. Logistic models were developed to assess the effect of disease status, test conditions, urine composition, and signalment on the performance of the V-BTA test. RESULTS: A total of 229 urine samples were analyzed, including 48 from dogs with suspected (n = 3) or confirmed (45) TCC. Test sensitivities were 88, 87, and 85% for all dogs with (suspected and confirmed) TCC, dogs with confirmed TCC at any site, and dogs with confirmed TCC of the urinary bladder, respectively. Test specificities were 84, 41, and 86% for healthy control dogs, unhealthy control dogs with non-TCC urinary tract disease, and unhealthy control dogs without urinary tract disease, respectively. The test performed slightly better on centrifuged urine samples than on uncentrifuged urine samples. CONCLUSIONS AND CLINICAL RELEVANCE: Our results indicate that the V-BTA test is useful in screening for urinary tract TCC in dogs.  相似文献   
956.
OBJECTIVE: To show the ability to obtain repeatable, accurate, quantitative data to assess the position of the femoral component of canine total hip implants using postoperative radiographs. STUDY DESIGN: Cadaveric study and clinical trial. ANIMALS: Five cadaveric canine femurs and 4 patients. METHODS: Femoral implants were placed into 5 cadaveric canine femurs in predetermined locations. Orthogonal radiographs were taken of each femur at 10 degrees intervals as they were moved through a natural range of hip motion. An assessment of implant position was made with each set of radiographs and analyzed to observe significant inconsistencies in the values obtained when the femur was repositioned. Three investigators positioned and radiographed the hips of 4 client-owned dogs that had total hip arthroplasty (THA). Each investigator obtained a set of orthogonal radiographic views from which implant position was measured. The measurements obtained from each investigator's set of radiographs were statistically analyzed to evaluate for interobserver differences. RESULTS: The methods described indicate that consistent data regarding femoral implant placement can be obtained from postoperative radiographs of THA patients. Under most circumstances, change in position of the femur did not significantly affect femoral implant measurements. There were no significant differences noted among values obtained by different investigators. CONCLUSIONS: Measurements based on the femoral and implant axes obtained from orthogonal radiographic views of the femur provide a means for obtaining accurate and consistent quantitative data regarding femoral implant position using postoperative radiographs of canine THA patients. CLINICAL RELEVANCE: Acquisition of quantitative information about femoral implant position using postoperative radiographs will facilitate development of a readily available data source. This information, attainable in a clinical setting, may help identify elements of implant position that are important in determining the clinical outcome of THA in dogs.  相似文献   
957.
958.
A rule-based expert system using CLIPS programming language was created to classify body cavity effusions as transudates, modified transudates, exudates, chylous, and hemorrhagic effusions. The diagnostic accuracy of the rule-based system was compared with that produced by 2 machine-learning methods: Rosetta, a rough sets algorithm and RIPPER, a rule-induction method. Results of 508 body cavity fluid analyses (canine, feline, equine) obtained from the University of California-Davis Veterinary Medical Teaching Hospital computerized patient database were used to test CLIPS and to test and train RIPPER and Rosetta. The CLIPS system, using 17 rules, achieved an accuracy of 93.5% compared with pathologist consensus diagnoses. Rosetta accurately classified 91% of effusions by using 5,479 rules. RIPPER achieved the greatest accuracy (95.5%) using only 10 rules. When the original rules of the CLIPS application were replaced with those of RIPPER, the accuracy rates were identical. These results suggest that both rule-based expert systems and machine-learning methods hold promise for the preliminary classification of body fluids in the clinical laboratory.  相似文献   
959.
Over the last 20 years, ultrasound has become a useful diagnostic tool in veterinary medicine. The purpose of this study was to use ultrasonographic examinations to determine if intra-abdominal contents could be visualized. Nineteen dogs, ranging from 8 months to 18 years of age were included. Each animal was evaluated sonographically prior to surgery, 24 h after surgery, and then 2-6 weeks following the surgical procedure. The results of our study suggest that ultrasound is an effective means for evaluation of the abdomen and surgery site following surgery. Both the abdomen and surgery site were clearly visualized in all dogs. In addition, subjective evaluation of the intra-abdominal contents was performed. The limiting factor in this study was not the presence of air, as was expected. Rather the limiting factor for appropriate visualization was pain. The information obtained could prove to be useful to surgeons and radiologists in assessing a patient's status postoperatively.  相似文献   
960.
During the spring and summer of 2001 and in association with the mare reproductive loss syndrome, 22 terminal and 12 clinical cases of equine pericarditis were diagnosed in central Kentucky. Actinobacillus species were the principal isolates from 8 of 10 nontreated, terminally affected and 3 of 10 clinically affected horses. Enterococcus faecalis and Streptococcus zooepidemicus were cultured from the remaining 2 nontreated terminal cases. No viruses were isolated in tissue culture. Nucleic acid of equine herpesvirus-2 was detected in pericardial and tracheal wash fluids of 3 and 1 individuals, respectively. Microscopic alterations in sections of heart and parietal pericardium were consistent with chronic fibrinous bacterial pericarditis. This report confirms a significant role of Actinobacillus species in equine pericarditis and describes an epidemic of this infrequently observed syndrome in the horse.  相似文献   
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