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81.
In sheep, alpha(2)-agonists can induce severe hypoxaemia. In goats, reports on changes in oxygenation are inconsistent. The aim of this study was to compare the cardiopulmonary effects of dexmedetomidine in six goats and four sheep anaesthetised with sevoflurane and maintained at approximately 1 minimal alveolar concentration. The animals were ventilated mechanically and held in an upright position to minimise the influence of positioning on pulmonary function. After baseline cardiopulmonary measures, 2 microg/kg dexmedetomidine was injected intravenously over one minute, and measurements were made for 120 minutes. In both species, respiratory resistance, alveolar dead space and shunt fraction increased and thoracic compliance decreased significantly; arterial, pulmonary arterial, pulmonary capillary wedge and central venous pressures increased and heart rate and cardiac output decreased significantly. Arterial oxygen tension decreased significantly, with no significant difference between the goats and sheep. Wide interindividual differences were observed in both the goats (mean [sd] 144 [149.1] mmHg, range 54.8 to 443.7 mmHg) and sheep (mean [sd] 129.8 [132.1] mmHg, range 33.7 to 352.8 mmHg), but the cardiovascular and respiratory changes were similar in the two species.  相似文献   
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83.
Cholangitis is a common inflammatory disorder of the biliary system in cats. There are two major forms based on the predominate type of inflammatory cell infiltrates: lymphocytic or neutrophilic. Ultrasound is a common imaging modality used in these patients. This retrospective study evaluated the ultrasound examinations of 26 cats with a histologic diagnosis of cholangitis. Most cats with cholangitis had sonographically normal liver size, echogenicity, and normal biliary systems. Statistically significant sonographic changes for cats with cholangitis included hyperechoic liver parenchyma, hyperechoic gallbladder contents, and increased pancreatic size. No statistically significant changes were noted to distinguish lymphocytic and neutrophilic forms of cholangitis. Cats with the sonographic features of diffuse liver hyperechogenicity, gallbladder contents and enlarged pancreas may suggest cholangitis.  相似文献   
84.
Diagnosis of Histoplasma capsulatum infection in cats traditionally relies upon identification of organisms in circulating monocytes or in tissue specimens from affected organs. In this retrospective study, results of a urine antigen assay were compared with standard diagnostic methods in cats with clinical signs suggestive of histoplasmosis. Antigenuria was detected in 17/18 cats with a histopathologic or cytopathologic diagnosis of histoplasmosis. This preliminary evaluation of the Histoplasma urine antigen test suggests it may be a useful aid in diagnosing this disease in cats.  相似文献   
85.
ObjectiveTo evaluate the accuracy of a new cardiac output monitor (FloTrac/Vigileo), originally designed for humans, in dogs. This pulse contour cardiac output monitoring system cannot be calibrated and measures cardiac output (
t) from a standard arterial catheter.Study designProspective experimental trial.AnimalsEight adult Beagle dogs weighing 13.1 (9.8–17.1) kg [median (range)].MethodsAnaesthesia in the dogs was maintained using isoflurane. A pulmonary artery catheter and a metatarsal arterial catheter (22 gauge) were placed. Cardiac output was measured simultaneously 331 times by thermodilution and FloTrac technique. A broad spectrum of
t measurements was achieved through alterations of isoflurane concentration, administration of propofol boluses and dobutamine infusions. Agreement between the methods was quantified with Bland Altman analysis and disagreement was assessed with linear mixed models.ResultsMedian (10th and 90th percentile) cardiac output as measured with thermodilution was 2.54 (1.47 and 5.15) L minute?1 and as measured with FloTrac 8.6 (3.9 and 17.3) L minute?1. FloTrac measurements were consistently higher with a mean bias of 7 L minute?1 and limits of agreement of ?3.15 to 17.17 L minute?1. Difference between the methods was most pronounced in high
t measurements. Linear mixed models showed an estimated difference between the two methods of 8.05 (standard error 1.18) L minute?1 and a significant interaction between mean arterial pressure and method. Standard deviation (4.45 higher) with the FloTrac method compared to thermodilution was increased.ConclusionCompared to thermodilution measurements, the FloTrac system was influenced to a higher degree by arterial blood pressure, resulting in consistent overestimation of cardiac output.Clinical RelevanceThe FloTrac monitor, whose algorithms were developed based on human data, cannot be used as an alternative for thermodilution in dogs.  相似文献   
86.
Benign and malignant splenic masses can appear similar on B-mode imaging, making ultrasound sensitive but not specific in their diagnosis. Our goal was to characterize color and/or power Doppler characteristics of vasculature within and adjacent to a splenic mass, which would distinguish benign vs. malignant lesions. The hypothesis was that malignant splenic masses will have altered vascular patterns compared with benign masses. Color and power Doppler cineloops evaluating the vasculature within the mass and normal splenic parenchyma were obtained in sagittal and transverse planes using a standardized protocol. Categories of evaluation included presence of peritoneal effusion, a large aberrant or tortuous vessel within the mass, relative blood flow within the mass compared with normal parenchyma, and path of vessels in the adjacent parenchyma entering into the mass. All patients had histopathologic or definitive cytologic diagnosis. Thirty-one dogs were included. There were 13 malignant masses and 18 were benign. Peritoneal effusion was significantly associated with malignancy (P = 0.0007). Presence of an aberrant or tortuous vessel within the mass was nearly significant (P = 0.059). There was no significant difference in any of the color or power Doppler blood flow evaluations. Ultrasonographic findings of a splenic mass and peritoneal effusion may indicate malignancy. The presence of an aberrant vessel within a splenic mass could suggest malignancy; however more data are needed.  相似文献   
87.
Between 65% and 91% of human‐patient sonographers report musculoskeletal symptoms related to their work activities. Ergonomic risk factors associated with musculoskeletal symptoms and musculoskeletal disorders (MSDs) include force, repetition, and awkward postures of the upper extremities. We hypothesized that veterinary sonographers experience similar risk factor exposures as their colleagues in human‐patient sonography, and that work‐related exposures may lead to similar prevalence of musculoskeletal symptoms and disorders. The Occupational Safety and Health Administration and Society of Diagnostic Medical Sonography published MSD prevention guidelines in 2003. Similar guidance for sonographers examining animal patients does not exist. This cross‐sectional study was designed to evaluate the prevalence of musculoskeletal symptoms among veterinary sonographers and identify reported risk factors. A 59‐item survey questionnaire was administered via email to veterinary specialists likely to perform ultrasound. Musculoskeletal pain related to performing ultrasound exams was reported by 62% of the respondents. Musculoskeletal symptoms were significantly associated with female gender (odds ratio [OR], 4.55; 95% confidence interval [CI], 2.04–10.19), age (OR, 1.06; 95% CI, 1.01, 1.10), previous work‐related trauma (OR, 6.86; 95% CI, 1.71, 27.40), not consistently using a normal height chair (OR, 2.63; 95% CI, 1.19, 5.80), and 15°–45° abduction of shoulder (OR, 2.34; 95% CI, 1.11, 4.92) . It was concluded that the prevalence of musculoskeletal symptoms among veterinary sonographers was similar to that occurring in human‐patient sonographers. © 2012 Veterinary Radiology & Ultrasound.  相似文献   
88.
Hemorrhagic septicaemia, an acute disease caused by P multocida capsular type B which is rarely detected in Europe, caused considerable losses in fallow deer, cattle and pigs within a region along the border of the federal states Brandenburg and Saxony-Anhalt in the summer of 2010. Clinical appearances and diagnostic findings are presented and possible triggering influences discussed. Pasteurella multocida capsular type B has not been cultivated from clinically healthy cattle and pigs of the region. Examination of fallow deer and roe deer in the region revealed the presence of singular carriers, which may act as a source of clinical infections.  相似文献   
89.
90.
Our objective was to determine factors that contribute to variation in bulk-tank-milk Salmonella Dublin enzyme-linked immunosorbent assays (ELISA) corrected optic-density measurements (ODC%) in dairy herds. We constructed hierarchical mixed models with repeated bulk-tank-milk ELISA ODC% in 31 Danish dairy herds. Four models included different combinations of explanatory factors, and we compared how well these models described the variation in the data. Herd was included as a random effect nested within Salmonella status and barn type.

Detection of Salmonella Dublin or Salmonella Typhimurium by bacteriological culture of individual faecal samples or of slurry samples was associated with higher bulk-tank-milk ELISA ODC%, as was apparent Salmonella prevalence, the mean ELISA ODC% or mean-yield-corrected ELISA ODC% in milk samples collected from all individual cows. However, combinations of risk factors that included number or prevalence of cows with a very high ELISA ODC% provided better models, indicating that the effect of the cow-level explanatory variables on the bulk-tank-milk ELISA ODC% was related to the activity of the infection in the herd. Barn type (loose housing or tie stalls) was not associated with the variation in bulk-tank-milk ELISA ODC% in these models, which might be useful in planning of surveillance programs and intervention strategies.  相似文献   

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