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51.
Anesthetic-associated death (AAD) in cats is infrequent, but occurs far more frequently than in people. Post-mortem investigations of AAD in cats are uncommon, and results only sporadically published. Here we report the findings in 54 cases of AAD in cats. Significant gross and/or microscopic pre-existing disease, including pulmonary, cardiac, and systemic disease, was detected in 33% of cases. Pulmonary disease was most frequently diagnosed (24% of cases), and included cases of Aelurostrongylus abstrusus infection (9% of cases). Heart disease, including two cases of hypertrophic cardiomyopathy, was less frequent (11% of cases). Four percent died from surgical complications. No?significant gross or microscopic disease was detected in 63% of cases. Additional studies are needed to determine if these findings are representative of AAD in cats in other geographic areas or with access to veterinary care. This study demonstrates that post-mortem investigation of AADs is an important and worthwhile endeavor.  相似文献   
52.
The goal of habitat restoration is to provide environmental conditions that promote the maintenance and growth of target populations. But rarely is it considered how the allocation of resources influences the diversity of phenotypes in these populations. Here we present a framework for considering how habitat restoration can shape the development and expression of phenotypes. We call this approach phenotype management as it entails restoring the resources in a habitat to manage phenotypic diversity. Phenotype management is achieved by manipulating the spatial and temporal distribution of resources to alter the degree of competition among individuals. Differences in competition, in turn, lead to changes in phenotypic and life history expression that affect population parameters including demography and effective population size (Ne). To illustrate how phenotype management can be applied, we explore how resource distributions shape variation in phenotypes in two imperiled fishes, Pacific salmon and desert pupfish. In both examples, modulating male reproductive phenotypes changes the allocation of reproductive success among population members to subsequently affect Ne. These examples further demonstrate that whether to increase or decrease phenotypic diversity depends on the primary conservation pressures faced by the species.  相似文献   
53.
A 3-year-old Thoroughbred colt was presented for evaluation of azotemia and anorexia. Physical examination revealed a ureterolith in the left ureter, approximately 10 cm from the bladder, which was thought to obstruct urine flow by approximately 90% when viewed cystoscopically. Ultrasonographic examination of both kidneys revealed indistinct corticomedullary junctions, and the right kidney was more hyperechoic. A percutaneous biopsy of the right kidney revealed chronic interstitial nephritis with marked interstitial medullary fibrosis. Medical therapy consisting of IV fluids, sodium chloride PO, and ammonium chloride PO was initiated. Ureteroscopic electrohydraulic lithotripsy via a perineal urethrostomy was used to successfully remove the stone. Klebsiella oxytoca , which responded to oral enrofloxacin therapy, was cultured from the urine after surgery. Azotemia resolved and the horse resumed training.  相似文献   
54.
The effect of a ketamine hydrochloride/acepromazine combination on the cardiopulmonary function of 11 healthy cats was studied. Test parameters included cardiac output, measured by thermodilution, heart rate, respiratory rate, arterial blood pressure (systolic, diastolic and mean) and arterial blood gas analysis. Values for systemic vascular resistance, cardiac index and stroke volume were calculated. The cardiac output, cardiac index, stroke volume, arterial blood pressure and arterial blood pH decreased significantly (p less than 0.006). The arterial CO2 increased significantly (p less than 0.006). All changes occurred during the five to 45 minute postinduction time period. The heart rate, respiratory rate, arterial O2 and systemic vascular resistance were not significantly altered. The anesthetic regime maintained an adequate plane of surgical anesthesia for 30-45 minutes.  相似文献   
55.
Experimentally-induced type 1 hypersensitivities were induced in normal dogs to either ovalbumin or Ascaris antigen. In vitro and in vivo cell-mediated immune responses were measured before sensitization and again at 1 and 6 days after induction of anaphylaxis by intravenous challenge with antigen. Histamine-modulated lymphocyte functions, such as histamine-induced suppression, histamine co-mitogen induced blastogenesis and the in vivo cutaneous responses to intradermally injected mitogens decreased post anaphylaxis. Spontaneous suppression of the autologous mixed-lymphocyte reaction increased post anaphylaxis. Lymphocyte blastogenic response to Concanavalin A (Con A) decreased at 6 (but not at 1) days post anaphylaxis probably due to a mediator other than histamine. Blastogenesis of 24 h preincubated cells by suboptimal concentration of Con A, declined post anaphylaxis, but Con A-induced suppression was not significantly altered. Dogs with atopic dermatitis have some altered cell-mediated immune responses. Altered histamine-induced and spontaneous suppression, histamine suppression of mitogenesis and decreased contact sensitivity observed in this experimental type 1 hypersensitivity mimicked that of atopic dogs. Increased cutaneous response to mitogens observed in atopic dogs was not reproduced in the type 1 hypersensitive dogs. These findings suggest some of the altered cell-mediated immune functions observed in dogs with atopic dermatitis result from type 1 hypersensitivity. The other abnormalities may be intrinsic to the atopic state.  相似文献   
56.
The isolation and characterization of 71 strains of slowly cytopathic herpesviruses (EHV2) from horses in Queensland is described. Specimens from aged horses at slaughter yielded 7 isolates from leucocytes and 4 from tonsils, but EHV2 strains could not be detected in salivary glands, spleen, kidney or intestinal wall. A further EHV2 strain (EK550) was isolated from cell cultures prepared from the kidney of an adult horse. Repeated sampling yielded 39 nasal, ocular and genital EHV2 strains from a group of 16 mares and their young foals, and 20 strains from a group of 6 yearlings.
Laboratory examination of these EHV2 strains demonstrated variations in plaque size and growth in non-host cell cultures, and at least two serological groups were detected. EHV2 infection of foals transplacentally was not detected, but neonatal infection of foals from chronically infected mares appeared probable.  相似文献   
57.
Intestinal healing and methods of anastomosis   总被引:1,自引:0,他引:1  
Optimal intestinal healing occurs when like layers of the intestinal wall are aligned. Hand-sewn, double-layer, end-to-end anastomosis that apposes the mucosa and produces slight inversion of the seromuscular layer is recommended to minimize adhesion formation and provide reasonable alignment of the intestinal layers. Stapled, everted, triangulated, end-to-end anastomosis is not recommended because of extensive adhesion formation and poor healing of the intestinal layers. The preferred stapled techniques create an inverting, side-to-side stoma between the bowel segments.  相似文献   
58.
Detailed physical and clinical examinations were performed on 26 Thoroughbred racehorses which were used subsequently in a series of studies to investigate the contribution of the pulmonary and bronchial arterial circulations to the pathophysiology of exercise-induced pulmonary haemorrhage (EIPH). Twenty-five of the horses had been retired from race training in Hong Kong during the 1984-85 season, all but four raced that season; one horse had been retired the previous season. The average number of races for the group that season was 4.1 +/- 2 with an average distance of 1502 +/- 216 metres, mean racing speed 15.5 +/- 0.5 metres/sec. Time from last race to necropsy was 177 +/- 155 days, range 12 to 572 days. All but one horse had a known history of either EIPH or epistaxis. Time from last recorded incident of expistaxis (17 horses) to necropsy was 156 +/- 141 days, range 12 to 513 days, with a longer interval since last recorded endoscopic observation of EIPH. Focal abnormal lung sounds were detected in the dorsocaudal lungfields on auscultation during rebreathing in three horses and six had tracheobronchial cytology consistent with previous episodes of pulmonary haemorrhage (haemosiderophages). No other characteristics which might have allowed separation of this group of horses from other Thoroughbred horses recently in race training were identified.  相似文献   
59.
Abnormal pulmonary radiopacities were identified in 13 racing horses in which a diagnosis of exercise-induced pulmonary hemorrhage (EIPH) had been confirmed. The lesions were in the caudal lung lobe in all horses; seven were on the right and three on the left, and the laterality for three could not be determined. In ten horses the opacities, which were large and peripherally located, obliterated the thoracophrenic angle. They merged with the silhouette of the diaphragm and had a circular or ovoid surface directed toward the hilum. The intensity of opacification of the consolidated areas varied, and they often were not sharply marginated. Dorsal displacement of the pulmonary arteries was noted in the region of the radiopacity in seven horses. Varying volumes of pleural effusion were observed in nine horses. Serial radiographic examinations were performed in seven horses. The pulmonary radiopacities cleared within ten days in two horses. In the remaining five horses, gradual resolution, characterized by a reduction in lesion size with improved margination, occurred during several months. The central region of the radiopaque lesion commonly had a patchy appearance, suggesting cavitation. Normal pulmonary vascular and interstitial markings were evident following complete resolution of these lesions. The cause of these abnormal pulmonary opacities has not been determined. Pathologic-radiologic correlations will be required to improve understanding of the pathophysiology of EIPH in the racing horse.  相似文献   
60.
This study was initiated to determine if the extent and intensity of lung lesions associated with exercise-induced pulmonary haemorrhage (EIPH) in horses could be predicted from thoracic radiographs. Sets of thoracic radiographs from 24 horses with varied histories of EIPH were subjectively coded for radiographic quality, and perceived extent and intensity of diffuse interstitial opacity by three radiologists who had no knowledge of the corresponding autopsy results. Codes assigned from radiographs for the chosen parameters were compared with coded estimates of lung surface staining assigned at post mortem and volume measurements of haemosiderin deposits and bronchial arterial neovascularisation recorded from lung slices in separate studies. The non-parametric Spearman rank correlation test was used to test for statistical significance. All radiographically coded estimates of lesion severity were positively correlated with post mortem measurements of actual lesion involvement, but only the correlation between coded estimates of lesion opacity versus haemosiderin deposits and bronchial artery neovascularisation were statistically significant (P less than 0.05). Correlations between radiographic codes for lesion extent versus haemosiderin deposits and neovascularisation were just beyond the level of significance (P greater than 0.05 less than 0.1). These findings indicate that there are graded, radiographically discernible increases in interstitial opacity related to actual lesion severity. However, under the conditions of the study, accurate prediction of lung pathology in individual cases based on radiographic criteria was precluded by the wide variance of the coded values. The authors believe that with good radiographic technique and careful criteria selection, satisfactory prediction of lesion severity in EIPH cases could be achieved.  相似文献   
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