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81.
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   
82.
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   
83.
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   
84.
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   
85.
86.
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   

87.
The objective of the study was to investigate the effect of offering supplementary creep feed to piglets during the suckling period on the faecal shedding of haemolytic Escherichia coli bacteria and occurrence of spontaneous post-weaning diarrhoea 0-5 days after weaning. Supplementary creep feed was offered to half of the piglets in 12 litters, from 2 weeks of age until weaning at 4 weeks, and the individual feed contact was recorded by direct observations. It was found that diarrhoea occurrence was associated with faecal shedding of haemolytic E. coli bacteria (p=0.003), specifically E. coli O149 (p=0.004). Occurrence of diarrhoea and faecal shedding of haemolytic E. coli was not associated with creep feeding per se. However, the faecal E. coli O149 shedding occurred significantly less often in piglets that were offered creep feed in the suckling period but only showed limited interest in the feed (i.e. contacted the feed less than or equal to the median level of contact) compared to piglets that had frequent creep feed contact or piglets that had not had access to creep feed at all (p=0.015). Correspondingly, the diarrhoea occurrence tended to be lower in these piglets (p=0.081). Piglets with low creep feed contact during the suckling period ate the same total amount of feed during the 5 days after weaning, however, they ate less feed on days 0-2 after weaning compared to the piglets with frequent creep feed contact and non-creep fed piglets. It is suggested that intestinal function associated with a voluntary low creep feed contact during the suckling period leads to decreased feed intake just after weaning, and thus reduces the intestinal proliferation of E. coli O149 in these piglets.  相似文献   
88.
OBJECTIVE: To determine clinical signs, diagnostic findings, outcome, and prognostic factors in dogs treated surgically for massive hepatocellular carcinoma (HCC) and compare survival times of surgically and conservatively treated dogs. DESIGN: Retrospective study. ANIMALS: 48 dogs. PROCEDURE: Medical records were examined for clinical signs, diagnostic and surgical findings, and postoperative outcome. Dogs were allocated into surgery and nonsurgery groups depending on whether curative-intent liver lobectomy was performed. Data from the surgical and nonsurgical groups were analyzed to identify prognostic factors and determine and compare rates of tumor control and survival time. RESULTS: 42 dogs were treated surgically, and 6 were managed conservatively. In the surgery group, intraoperative mortality rate was 4.8% with no local recurrence, metastatic rate was 4.8%, and median survival time was > 1,460 days (range, 1 to 1,460 days). High alanine aminotransferase and aspartate aminotransferase activities were associated with poor prognosis. Median survival time for the nonsurgery group was 270 days (range, 0 to 415 days), which was significantly less than that of surgically treated dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Liver lobectomy is recommended for dogs with massive HCC because tumor-related mortality rate was 15.4 times higher in dogs in the nonsurgery group, compared with the surgery group. Tumor control was excellent after surgical resection with no local recurrence and a low metastatic rate. Prognostic factors were identified, but their clinical relevance was uncertain because only 9.5% of dogs in the surgery group died as a result of their disease.  相似文献   
89.
Polycystic kidney disease (PKD) in Persian cats has been increasingly reported and compared to human autosomal dominant polycystic kidney disease (ADPKD) in the last decade. In cats, however, few studies have dealt with the occurrence and hormonal determinants of hypertension, one of the most common extrarenal manifestations of ADPKD in humans. The purpose of this study was to compare Persian cats >4 years old with PKD to unaffected control cats with regard to blood pressure (BP), plasma renin activity (PRA), serum aldosterone concentration, plasma atrial natriuretic peptide (ANP) concentration, and aldosterone-to-renin ratio (ARR). Three gender- and age-matched groups were studied, each consisting of 7 cats: (1) a control group without cysts, (2) a group with mild PKD, and (3) a group with severe PKD (multiple cysts and renal enlargement). Mild renal insufficiency was found in only 1 of 14 cats with PKD. Cats with PKD had a higher mean arterial pressure (P = .04) and more often had a high ARR (P = .047) than did control cats. Tendencies toward higher diastolic and systolic arterial pressures (DAPs and SAPs, respectively) and lower PRAs were observed in cats with PKD compared to controls (.05 < P < or = .1). No significant differences were found between the groups in serum aldosterone and plasma ANP concentrations. None of the cats had echocardiographic evidence of cardiac hypertrophy. In conclusion, cats with PKD had a minor increase in mean arterial pressure compared to control cats, and half of the cats had a high ARR.  相似文献   
90.
Hietel  Elke  Waldhardt  Rainer  Otte  Annette 《Landscape Ecology》2004,19(5):473-489
Land-use and land-cover changes affect ecological landscape functions and processes. Hence, landscape ecologists have a central interest in a comprehensive understanding of such changes. Our study focuses on the relationships between environmental conditions and agricultural land-cover changes. We present a method to (i) characterise the major spatial-temporal processes of land-cover changes, (ii) identify the correlations between environmental attributes and land-cover changes and (iii) derive potential environmental drivers of land-cover changes in a German marginal rural landscape. The method was applied to study land-cover dynamics from 1945 to 1998 in the districts of Erda, Steinbrücken and Eibelshausen, situated in the marginal rural landscape of the Lahn-Dill Highlands, Germany. We employed land-cover data gained by the interpretation of multi-temporal aerial photographs. Various environmental variables were introduced into the analyses. We identified physical landscape attributes (elevation, slope, aspect, available water capacity and soil texture) and structural landscape dimensions (patch size, patch shape and distance between patch and nearest settlement). With the aid of GIS, K-means partitioning and canonical correspondence analysis, we investigated land-cover trajectory types, land-cover transitions at individual time intervals and their relationships to these environmental variables. Our results show that, between 1945 and 1998, land-cover changes correlated with the physical attributes of the underlying landscape. On the other hand, the structural landscape dimensions correlated with land cover only in periods of minor land-cover changes (1972–98). Greater diversity of physical landscape attributes is correlated with greater land-cover dynamics. Besides the important influence of socio-economic factors, land-cover changes in the study areas took place within the relatively stable physical constraints of the underlying landscape.This revised version was published online in May 2005 with corrections to the Cover Date.  相似文献   
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