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51.

Objectives

To assess the ability of electrocardiography (ECG) to predict left ventricular hypertrophy (LVH) in the cat and to investigate the prognostic value of selected ECG variables in cats with LVH.

Animals

Fifty-seven privately owned cats: 22 clinically healthy cats and 35 cats with LVH.

Material and methods

This is a clinical cohort study. Echocardiographic diagnosis and surface ECG were available. Electrocardiography analysis included rhythm diagnosis and specific electrocardiographic measurements. In cats with LVH, cause of death and outcome data were recorded and analyzed using Kaplan–Meier curves.

Results

The presence of arrhythmia had sensitivity and specificity of 31% and 100%, respectively, for identifying LVH. Among ECG measurements, duration of QT interval (QT) and QT interval corrected for heart rate (QTc) was statistically different between healthy cats and cats with LVH (p = 0.007). Overall, the most accurate cutoffs to identify LVH were QT > 170 ms (sensitivity and specificity 48.3% and 91%, respectively) and QTc > 188 ms (sensitivity and specificity 62% and 77%, respectively). In healthy cats, the highest QT and QTc values were 180 ms and 200 ms, respectively. Mean survival time was 58 days and indeterminable for cats with QT > 180 ms and QT ≤ 180 ms, respectively (p = 0.042) and 125 days and indeterminable for cats with QTc > 200 ms and QTc ≤ 200 ms, respectively (p = 0.017).

Conclusions

Arrhythmias as well as prolonged QT and QTc are useful ECG parameters in identifying LVH and predicting survival in affected cats.  相似文献   
52.
ObjectivesTo evaluate whether a period of hyperoxia or after a period of hypoxia produced changes attributable to reactive oxygen species in anaesthetized horses.Study designProspective randomized experimental study.AnimalsSix healthy (ASA I) geldings, aged 4.5–9.5 years and weighing 510–640 kg?1.MethodsAfter 30 minutes breathing air as carrier gas for isoflurane, horses were assigned randomly to breathe air as carrier gas (CG0.21) or oxygen as carrier gas (CG1.00) for a further 90 minutes. After an interval of 1 month each horse was re-anaesthetized with the other carrier gas for the 90 minute test period. Ventilation was controlled throughout anaesthesia. Arterial blood was sampled to measure gas tensions, lactate, cholesterol, vitamin E, 4-hydroxy-alkenals, 8-epi-PGF, half haemolysis time, half erythrolysis time, and erythrocyte membrane fluidity. Muscle blood flow and oxygenation were evaluated by near infrared spectroscopy and coloured Doppler.ResultsAfter the first 30 minutes horses were hypoxemic. Subsequently the CG1.00 group became hyperoxaemic (PaO2~240 mmHg) whereas the CG0.21 group remained hypoxaemic (PaO2~60 mmHg) and had increased lactate concentration. No significant changes in vitamin E, 4-hydroxy-alkenals, or 8-epi-PGF concentrations were detected. During the 90 minute test period the CG0.21 group had increased resistance to free-radical-mediated lysis in erythrocytes, whereas the CG1.00 group had slightly decreased resistance of whole blood to haemolysis. CG0.21 induced a progressive muscle deoxygenation whereas CG1.00 induced an increase in muscle oxygen saturation followed by progressive deoxygenation towards baseline.Conclusions and clinical relevanceDuring isoflurane anaesthesia in horses, the hyperoxia induced by changing from air to oxygen induced minimal damage from reactive oxygen species. Using air as the carrier gas decreased skeletal muscle oxygenation compared with using oxygen.  相似文献   
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Partly due to climate change, and partly due to changes of human habitat occupation, the impact of tick-borne viruses is increasing. Nairobi sheep disease virus (NSDV) and Ganjam virus (GV) are two names for the same virus, which causes disease in sheep and goats and is currently known to be circulating in India and East Africa. The virus is transmitted by ixodid ticks and causes a severe hemorrhagic disease. We have developed a real-time PCR assay for the virus genome and validated it in a pilot study of the pathogenicity induced by two different isolates of NSDV/GV. One isolate was highly adapted to tissue culture, grew in most cell lines tested, and was essentially apathogenic in sheep. The second isolate appeared to be poorly adapted to cell culture and retained pathogenicity in sheep. The real-time PCR assay for virus easily detected 4 copies or less of the viral genome, and allowed a quantitative measure of the virus in whole blood. Measurement of the changes in cytokine mRNAs showed similar changes to those observed in humans infected by the closely related virus Crimean Congo hemorrhagic fever virus.  相似文献   
55.
A 7-year-old spayed female Cocker Spaniel was hospitalized with a history of chronic vomiting, anorexia, and weight loss. Laboratory abnormalities included leukocytosis, metabolic alkalosis, hypoglycemia, hypoproteinemia, and hyperinsulinemia. Gastroscopy and ultrasonography revealed multiple gastric masses and a possible pancreatic mass, respectively. Examination of tissues obtained at necropsy showed a pancreatic adenocarcinoma with hepatic metastasis, gastric hypertrophy, and multiple duodenal ulcers. Immunocytochemical staining of the neoplasia was positive for pancreatic polypeptide (PP) and insulin and negative for gastrin, calcitonin, adrenocorticotropic hormone (ACTH), serotonin, L-enkephalin, chromagranin, glucagon, and somatostatin. Subsequent serum gastrin and PP assays showed a fasting hypergastrinemia with a normal response of gastrin to provocative testing and extremely increased PP values. The high PP values may have resulted in the vomiting and gastrointestinal ulceration. A PP-secreting tumor has not previously been reported in the dog.  相似文献   
56.
The influence of an antigen-specific cellular and humoral immune response, stimulated by immunization, on survival of a challenge infestation of Hypoderma lineatum was investigated. Calves immunized with a purified combination of hypodermin A, B and C plus monophosphoryl lipid A (MPL) developed a strong antigen-specific cellular immune response by completion of the immunization schedule which persisted to 12 weeks post-infestation. Responsiveness of peripheral blood lymphocytes to the mitogens concanavalin A and pokeweed was also elevated at 4 and 12 weeks post-infestation. Western blot analysis at the time of maximum grub counts demonstrated that immunized calves responded to hypodermin A, B and C while those receiving only MPL or infested controls responded only to hypodermin B and C. The antigen-specific antibody response as measured by ELISA at maximum grub count was significantly higher in vaccinated calves than in infested controls while the response in calves receiving only immunostimulator was also significantly elevated. Immunized (antigen plus MPL) calves produced 5.0 +/- 6.9 grubs per animal which successfully pupated while those receiving MPL alone produced 16.4 +/- 6.1 and infested controls produced 32.2 +/- 10.9 grubs per animal.  相似文献   
57.
Griseofulvin administration was associated with the development of absolute neutropenia in six of seven (86%) cats with feline immunodeficiency virus (FIV) infection. The neutropenia was severe (less than 400 neutrophils/microliter) in four of the six affected cats, and one cat died from sepsis. Neutrophil counts returned to baseline values within 15 days after drug withdrawal in all surviving cats. No symptoms or hematologic abnormalities were observed in four normal (FIV-seronegative) cats treated with the same lot of griseofulvin at equivalent doses. Neutropenia recurred in two of two FIV-seropositive cats upon griseofulvin rechallenge. Cats with FIV infections appear to be at increased risk for griseofulvin-associated neutropenia. This phenomenon may be analogous to the increased frequency of antibiotic-induced neutropenias observed in humans infected with the human immunodeficiency virus.  相似文献   
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