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Romain Pariaut Carley Saelinger Jorge Vila William Deforge Patricia Queiroz-Williams Hugues Beaufrère Michael Zimmerman Katrin Saile Caryn A. Reynolds 《Journal of Veterinary Cardiology》2012,14(3):389-398
BackgroundImplantable cardioverter defibrillators (ICD) are programmed to detect ventricular arrhythmias and terminate them by delivering an electrical shock. A defibrillation threshold (DFT) at least 10 J below the maximum device output is recommended for successful therapy. Shock waveform configuration is a programmable parameter used to achieve a low DFT. It is hypothesized that a fixed-pulse configuration results in lower defibrillation energy requirements than a fixed-tilt configuration.Animals10 mongrel dogs.Materials and methodsICD generator and transvenous lead were surgically implanted. Defibrillation threshold was determined using a protocol guided by the upper limit of vulnerability. Fixed-pulse and fixed-tilt (50%/50%) waveform configurations were tested in a random order. Plasma cardiac troponin I (cTnI) was measured for signs of myocardial injury.ResultsThe experiment was completed in 9 dogs. Overall mean DFT value was 424 ± 88 V (9.2 ± 3.9 J). Mean differences among voltage, energy and impedance at the DFT for fixed-pulse (422 ± 97 V, 9.1 ± 4.2 J, 62.6 ± 13.8 Ω) and fixed-tilt (426 ± 83 V, 9.3 ± 3.8 J, 62.8 ± 18.5 Ω) configurations were not statistically significant (All P > 0.21). Cardiac TnI concentration changed from 0.03 ng/mL (95% CI: 0.02–0.04) at baseline to 0.11 ng/mL (95 CI: 0.08–0.16) after DFT was obtained with the first waveform configuration and 0.19 ng/mL (95% CI: 0.13–0.28) at the end of the study period. There were no significant changes in heart rate, end-tidal CO2 and blood pressure over time (all P > 0.09).ConclusionThe tested ICD device and lead placement reliably produced acceptable DFT values, based on a 10-J safety margin below the maximum device output. A benefit of fixed-pulse configuration could not be demonstrated over the standard fixed-tilt waveform. Signs of acute myocardial damage from repeated high-voltage shocks and episodes of ventricular fibrillation seemed of limited clinical significance. 相似文献
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Matthew Capitanio Dawn M Zimmerman Michael Douglass Terry Dew 《Journal of zoo and wildlife medicine》2008,39(2):270-273
A 16-yr-old, castrated male lion-tailed macaque (Macaca silenus) presented with acute bilateral pelvic limb paralysis. Cisternal and lumbar myelograms demonstrated right-sided spinal cord compression at T13-L1. During an extradural hemilaminectomy, chronically ruptured disk material was removed at T13-L1, with moderate venous dilatation observed cranially. The macaque fully recovered from clinical signs within 2 mo. 相似文献
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Simpson BS Landsberg GM Reisner IR Ciribassi JJ Horwitz D Houpt KA Kroll TL Luescher A Moffat KS Douglass G Robertson-Plouch C Veenhuizen MF Zimmerman A Clark TP 《Veterinary therapeutics : research in applied veterinary medicine》2007,8(1):18-31
Canine separation anxiety is a common behavioral problem presented to veterinarians. Associated behaviors are distressing to both dog and owner, have the potential to disrupt the human-companion animal bond, and may lead to euthanasia. The results of this study demonstrate the clinical efficacy and safety of Reconcile (fluoxetine, 1 to 2 mg/kg/day [0.45 to 0.91 mg/lb/day]), in conjunction with behavior management, for the treatment of canine separation anxiety. The beef flavored chewable formulation was palatable to treated dogs and easy to administer. This study provides to veterinarians and owners valuable information about an effective separation anxiety treatment plan that combines use of Reconcile with behavior modification. 相似文献
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A partial skeleton of a primitive bird, Rahona ostromi, gen. et sp. nov., has been discovered from the Late Cretaceous of Madagascar. This specimen, although exhibiting avian features such as a reversed hallux and ulnar papillae, retains characteristics that indicate a theropod ancestry, including a pubic foot and hyposphene-hypantra vertebral articulations. Rahona has a robust, hyperextendible second digit on the hind foot that terminates in a sicklelike claw, a unique characteristic of the theropod groups Troodontidae and Dromaeosauridae. A phylogenetic analysis places Rahona with Archaeopteryx, making Rahona one of the most primitive birds yet discovered. 相似文献
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对猪行为和福利的初探 总被引:1,自引:0,他引:1
1前言
早在公元前10 000年,东南亚就可能出现了野猪的驯化(Lekagul和McNeely,1977)。早期农业社会时,猪驯养变得普遍起来,可能是因为猪具有顽强的生命力、性成熟快、产仔数多以及饲喂粗饲料就可以保证维持自身营养需要的优势。 相似文献