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1.
The cardiorespiratory effects of morphine and butorphanol in horses anaesthetised under clinical conditions 总被引:2,自引:2,他引:0
Twenty-five horses admitted for minor orthopaedic or soft tissue surgery were anaesthetised with detomidine, ketamine and halothane. Heart rate, arterial blood pressure, respiratory rate, tidal volume, minute volume, blood gases and occlusion pressures were measured before and for 30 mins after intravenous (iv) injection of saline, butorphanol 0.05 mg/kg bodyweight (bwt) or morphine 0.02 or 0.05 mg/kg bwt. Drug or saline treatment induced no significant changes from pre-treatment values within a group for arterial blood pressure, heart rate, respiratory rate, arterial carbon dioxide tension, arterial oxygen tension and occlusion pressure. In conclusion, both morphine and butorphanol at the stated doses cause no adverse effects on the cardiovascular and respiratory systems of anaesthetised horses. 相似文献
2.
Concentrations and turnover numbers have been determined for the critical acetylcholinesterase component of the organophosphorus susceptible Yeerongpilly and resistant Biarra and Ridgelands strains. The lower specific activity for the substrate acetylthiocholine in the resistant strains was shown to be due to decreased catalytic efficiency and not to any change in the titer of the enzyme. Thioester analogs of acetylthiocholine, with additional methylene groups between the carbonyl carbon and the quaternary nitrogen of the molecule and in the alkyl moiety, have been used to derive Km and Vmax values for the enzymes from each strain. An hypothesis is proposed concerning the alteration of the active site that has occurred to produce the dissimilar aberrant enzymes of the resistant strains and the implications of this hypothesis for inhibitor design are discussed. 相似文献
3.
The critical acetylcholinesterase component, that is responsible for the resistance mechanism of decreased sensitivity to the inhibitor in the cattle tick Boophilus microplus (Can.), has been isolated from the organophosphorus-susceptible Yeerongpilly and resistant Biarra and Ridgelands strains. With the substrate acetylthiocholine this enzyme component gave a pH activity profile similar for all strains. Optimal substrate concentration for Ridgelands was 1.73.10?2M compared to 2.70.10?4M for the other strains. Computed Km values were 1.98.10?5M, 3.65.10?5M, and 6.43.10?6M for Yeerongpilly, Biarra, and Ridgelands strains, respectively, while the corresponding Vmax figures were 336, 135, and 21 μmoles acetylthiocholine hydrolyzed per gram of larvae per hour. These results are discussed in relation to the resistance mechanism and compared with similar parameters derived for this enzyme from bovine erythrocytes, the sheep blowfly Lucilia cuprina, and the sheep nematode Trichostrongylus colubtiformis. 相似文献
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Kara A. Brown Amy L. Johnson Susan J. Bender Thomas J. Nolan Bianca Pfisterer JoAnn Slack Elinor Willis Emily K. Rule 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2023,37(2):735-739
A 5-year-old imported Zangersheide gelding was evaluated for SC swellings over both forelimbs and lameness localized to the distal metacarpus. Ultrasound examination of the SC masses was compatible with verminous granulomas. Linear hyperechoic foci were present within the suspensory ligament branches of both forelimbs, suggestive of ligamentous parasitic infiltrates. A diagnosis of onchocerciasis was confirmed on biopsy of a SC mass. The gelding was treated with ivermectin and a tapering course of PO dexamethasone but was eventually euthanized. Necropsy confirmed the presence of SC eosinophilic granulomas and degenerative suspensory ligament desmitis, both with intralesional nematodes. Given the location and appearance of the nematode, a diagnosis of Onchocerca sp., most likely O. reticulata, was made. Onchocerciasis should be included as a differential diagnosis for multifocal suspensory ligament desmitis with these sonographic characteristics when paired with SC masses in imported European Warmbloods. 相似文献
6.
Colibacillosis caused by Escherichia coli infections account for significant morbidity and mortality in the poultry industry. Yet, despite the importance of colibacillosis, much about the virulence mechanisms employed by avian E. coli remains unknown. In recent years several genes have been linked to avian E. coli virulence, many of which reside on a large transmissible plasmid. In the present study, a multiplex polymerase chain reaction (PCR) protocol to detect the presence of four of these genes is described. Such a protocol may supplement current diagnostic schemes and provide a rapid means of characterizing the E. coli causing disease in poultry. The targets of this procedure included iss, the increased serum survival gene; tsh, the temperature sensitive hemagglutinin gene; cvi, the ColV immunity gene; and iucC, a gene of the aerobactin operon. Organisms, known for their possession or lack of these genes, were used as a source of the template DNA to develop the multiplex PCR protocol. Identity of the amplicons was confirmed by size, DNA:DNA hybridization with specific gene probes, and DNA sequencing. When the multiplex PCR protocol was used to characterize 10 E. coli isolates incriminated in avian colibacillosis and 10 from the feces of apparently healthy birds, nine of the isolates from apparently healthy birds contained no more than one gene, while the 10th contained all four. Also, eight of the isolates incriminated in colibacillosis contained three or more genes, while the remaining two contained two of the target genes. Interestingly, the isolates of sick birds containing only two of the targeted genes killed the least number of embryos,and the isolate of healthy birds that contained all the genes killed the most embryos amongthis group. These genes were not found among the non-E. coli isolates tested, demonstrating the procedure's specificity for E. coli. Overall, these results suggest that this protocol might be useful in characterization and study of avian E. coli. 相似文献
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Relationship between physiological factors and clinical pain in dogs scored using a numerical rating scale 总被引:1,自引:0,他引:1
L. L. Holton E. M. Scott † A. M. Nolan J. Reid E. Welsh 《The Journal of small animal practice》1998,39(10):469-474
A study was designed to investigate the association between heart rate, respiratory rate and pupil dilation and a subjective pain score allocated using a numerical rating scale (NRS). Four groups of dogs (n = 17 to 20 per group) were included: orthopaedic surgery cases, soft tissue surgery cases, dogs with medical conditions and healthy dogs. Each dog was examined by five veterinary surgeons within a four-hour period. When examining each dog, the observers recorded heart rate, respiratory rate, pupil dilation (present or absent) and a pain score using a NRS (range 0 to 10). For surgical cases, all study assessments were carried out between 21 and 27 hours following the end of surgery. The correlation coefficients between physiological parameters and NRS score were small but, depending on the analysis, were significant for heart rate and NRS score (P < 0·05). However, the size of the coefficient, 0·168, indicated that the relationship was not biologically significant. There was no association between respiratory rate and NRS score. Analysis of the relationship between NRS score and pupil dilation indicated that there was an association between this factor and pain, depending on the analysis. This was significant for the surgical groups (P < 0·05) but not for the other groups.
These findings indicate that heart rate and respiratory rate are not useful indicators of pain in hospitalised dogs. It is also unlikely that pupil dilation will be a useful tool in the assessment of pain. 相似文献
These findings indicate that heart rate and respiratory rate are not useful indicators of pain in hospitalised dogs. It is also unlikely that pupil dilation will be a useful tool in the assessment of pain. 相似文献
10.
Gates, M.C., Nolan, T.J. Efficacy of heartworm preventatives against ascarids and hookworms in client‐owned dogs: a retrospective case control study. J. vet. Pharmacol. Therap. 34 , 116–119. The efficacy of heartworm preventatives against ascarids and hookworms was assessed in a retrospective analysis of 1329 dogs that received a fecal examination and were surveyed about heartworm preventative use upon presentation to the veterinary teaching hospital at the University of Pennsylvania. To remove confounding due to age, patients under 6 months old were analyzed separately from the remaining population. Although there were no reported cases of ascarids or hookworms in patients under 6 months old receiving monthly heartworm prevention, the prevalence reached 5.2% and 11.7%, respectively, in patients that were not using any products. For patients over 6 months old, there were no apparent associations between parasites and heartworm preventative use. Of the 75.5% of dogs that were administered heartworm preventatives, 16.1% reported seasonal use and 83.9% reported using the products year round. Patients using heartworm preventatives seasonally were no more likely to be harboring nematode parasites than patients using preventatives year round (OR = 0.70, 95% CI: 0.19–2.55). Overall efficacy rates were consistent with prior studies on the active ingredients. Heartworm preventative have the greatest value for controlling nematode endoparasites in patients under 6 months old. 相似文献