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131.
132.
OBJECTIVES: To assess the use of Holter monitoring for evaluating the incidence of post-anaesthetic cardiac arrhythmias and associated anaesthetic risk for two different anaesthetic protocols. METHODS: Patients undergoing orthopaedic surgery were randomly divided into two groups with different anaesthetic regimens (group A, isoflurane n = 30; group B, propofol n = 30). Two 24-hour Holter recordings were performed for each patient: the first directly following anaesthesia and the second, as a comparison, on the fifth postoperative day. RESULTS: Although all dogs were healthy on pre-anaesthetic cardiac evaluation, 56 dogs showed arrhythmias in the two 24-hour (Holter) electrocardiograms performed. However, the number of arrhythmias recorded was low in most cases (less than 10 supraventricular extrasystoles and less than 100 ventricular extrasystoles). One patient in group A showed 94 supraventricular extrasystoles during the second monitoring period. Three patients in each group developed more than 100 ventricular extrasystoles during both Holter recordings. There were no statistically significant differences between the two anaesthetic regimens or between the two recordings in both groups. CLINICAL SIGNIFICANCE: The two anaesthetic protocols investigated in this study did not induce an increased incidence of severe arrhythmias in healthy dogs in the post-anaesthetic phase.  相似文献   
133.
Vedaprofen is a chiral nonsteroidal anti-inflammatory drug that has been developed as a gel formulation for oral administration to dogs and horses. The pharmacokinetics of vedaprofen and its enantiomers were studied in beagle dogs after single (intravenous solution and oral gel) and multiple (oral gel) dosing at a dosage of 0.5 mg/kg body weight. Plasma concentrations of vedaprofen and its enantiomers were analysed by HPLC. The plasma protein binding of vedaprofen was studied by ultrafiltration. The absorption of vedaprofen was rapid (tmax 0.63 +/- 0.14 h) and almost complete after oral administration (bioavailability 86 +/- 7%). The terminal half-lives after intravenous and oral administration, 16.8 +/- 2.2 and 12.7 +/- 1.7 h respectively, were of the same order of magnitude. Enantioselective analysis showed that the R(-) enantiomer predominated in plasma. The change in the plasma time course of the plasma R(-)/S(+) enantiomer concentration ratio over time was similar after single intravenous and oral dosing, with R(-)/S(+) ratios in the AUC of 1.7 +/- 0.5 and 1.9 +/- 0.2 respectively. Plasma protein binding of vedaprofen and its enantiomers was high (> 99.5%). Vedaprofen is absorbed rapidly from the gastrointestinal tract, has a high bioavailability and does not accumulate in plasma in dogs following repeated oral administration.  相似文献   
134.
135.
The association between scrapie and polymorphisms of the prion protein (PrP) gene was studied in 1108 German sheep of 33 different breeds. The aim of the investigation was the determination of the codons 136, 154 and 171 of the PrP gene, which are important for scrapie susceptibility. In addition to the published allelic variants ARR, ARQ, AHQ, ARH and VRQ, two novel, rare haplotypes (AHR and VRR) were found in the breeds of Texel, Nolana and Suffolk. A comparison of PrP genotype frequencies among the analysed different breeds revealed distinct variations. Breeds such as Texel showed a complex genotype distribution over 17 variants, while breeds such as Friesian Milk Sheep indicated only seven different genotypes.  相似文献   
136.
Phenylbutazone was administered intravenously to a group of 11 beef steers at a dosage of 6 mg/kg of body weight. Whole plasma and protein-free plasma were analyzed for phenylbutazone residues. Pharmacokinetic parameters of total and free phenylbutazone in plasma were calculated using a noncompartmental method. In regards to whole plasma data, the mean volume of distribution at steady state (Vss), was 140 mL/kg body weight, with a mean (+/-SEM) terminal elimination half-life (t1/2) of 34 +/- 9 h. The mean clearance was 3.2 mL/h/kg body weight. The Vss, as determined from the protein-free plasma fraction, was 54093 mL/kg body weight. This larger Vss of free phenylbutazone compared with total plasma phenylbutazone was attributed to a high degree of plasma protein binding, as well as the greater penetration of free phenylbutazone into tissues. The mean t1/2 of free phenylbutazone was 35 +/- 12 h. This similarity to the t1/2 estimated from total plasma phenylbutazone data is attributed to an equilibrium between free and plasma phenylbutazone during the terminal elimination phase. The pharmacokinetic parameters of free and total plasma phenylbutazone in beef steers are statistically similar to those previously reported for lactating dairy cows.  相似文献   
137.
Forty-six cats with clinical haemobartonellosis were studied; 75 per cent of the cats of known age were two-and-a-half years old or younger, 50 per cent were intact males and 19.5 per cent were castrated males. The predominant signs of the disease were tachypnoea, lethargy, depression, anorexia, infestation with fleas, pale mucous membranes, icterus, emaciation, dehydration, splenomegaly, anaemia, leucocytosis, increased activities of alanine aminotransferase and aspartate aminotransferase, and azotaemia. Thirty-eight per cent of the cats that were tested for feline leukaemia virus (FeLV) antigen were positive, and 22 per cent of those tested for feline immunodeficiency virus (FIV) antibodies were positive. The prevalence of both FeLV and FIV was much higher than in the general Israeli cat population. The cats infected with both Haemobartonella felis and FeLV had a significantly lower body temperature, were more anaemic and the mean cell volume of their erythrocytes was greater than in the cats with haemobartonellosis alone.  相似文献   
138.
The conduct of randomized controlled trials in livestock with production, health, and food-safety outcomes presents unique challenges that might not be adequately reported in trial reports. The objective of this project was to modify the CONSORT (Consolidated Standards of Reporting Trials) statement to reflect the unique aspects of reporting these livestock trials. A 2-day consensus meeting was held on November 18–19, 2008 in Chicago, IL, to achieve the objective. Before the meeting, a Web-based survey was conducted to identify issues for discussion. The 24 attendees were biostatisticians, epidemiologists, food-safety researchers, livestock production specialists, journal editors, assistant editors, and associate editors. Before the meeting, the attendees completed a Web-based survey indicating which CONSORT statement items would need to be modified to address unique issues for livestock trials. The consensus meeting resulted in the production of the REFLECT (Reporting Guidelines for Randomized Control Trials) statement for livestock and food safety and 22-item checklist. Fourteen items were modified from the CONSORT checklist, and an additional subitem was proposed to address challenge trials. The REFLECT statement proposes new terminology, more consistent with common usage in livestock production, to describe study subjects. Evidence was not always available to support modification to or inclusion of an item. The use of the REFLECT statement, which addresses issues unique to livestock trials, should improve the quality of reporting and design for trials reporting production, health, and food-safety outcomes.  相似文献   
139.
Paramphistomiasis is a disease of domestic and wild ruminants caused by some digenetic trematodes of the superfamily Paramphistomoidea. Human infections with certain species of paramphistomes have been reported. Given their ubiquity and their abundance within hosts, it seems likely that the importance of these worms is underestimated globally. Based on the reported difficulties of morphological identification of paramphistomes, the development of alternative approaches to better delineate species is needed. Paramphistome samples examined during this study were cercariae, rediae from snail hosts and adult flukes obtained from slaughterhouses from Kenya, Tanzania, Egypt and Nepal. The results confirm that ITS2 is a good molecular marker for paramphistome identification and can be used to determine the affiliation of samples among the different taxa of Paramphistomoidea. Our 22 samples include eight species of paramphistomes. Ten samples of paramphistome larvae (cercariae or rediae) yielded seven species and the 12 samples of adult flukes from bovines yielded four, only one of which was not also represented among the larvae. We found three cases in which the sequences for adult worms and larvae matched, thus revealing the hosts involved locally in those particular life cycles. We interpret our specimens to include five species from Kenya, two from Nepal, two from Tanzania and one from Egypt. Bulinus forskalii was found infected with three species of paramphistomes. The results of the present study will help construct a framework to facilitate identification and eventually control of this underestimated cosmopolitan group of digeneans.  相似文献   
140.
The ecology of avian influenza (AI) viruses in wild aquatic birds of Asia is poorly understood, especially for the H5N1 high pathogenicity AI (HPAI) viruses. From March 2006 through November 2008, 20 AI viruses were isolated in the Crimea region of Ukraine with an overall frequency of virus recovery of 3.3%. All the viruses were isolated from three species of dabbling ducks: mallard (Anas platyrhynchos), wigeon (Anas penelope), and garganey (Anas querquedula), making the frequency of virus recovery for dabbling ducks 6.3%. The viruses were predominantly isolated during the fall sampling period. All viruses were genetically and antigenically characterized. No H5N1 HPAI viruses were isolated, but other HA and NA subtypes were identified including H3N1 (2), H3N6 (3), H3N8 (4), H4N6 (6), H5N2 (3), H7N8 (1), and H10N6 (1) subtypes. All isolates were of low pathogenicity, as determined by the intravenous pathogenicity index of 0.00. For H5N2 and H7N8 isolates, the HA gene was sequenced and the phylogenetic analysis revealed possible ecologic connections of the Crimea region with AI viruses from Siberia and Europe. No influenza A isolates were recovered from other Anseriformes (diving ducks [two species of pochards] and graylag geese), Columbiformes (collared doves), Gruiformes (coot), and Galliformes (gray partridges).  相似文献   
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