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81.
82.
Objective Correlation of immunophenotype with history, anatomical and morphological features of lymphoid neoplasia in the koala.
Methods Routine necropsies were performed on 51 koalas with suspected lymphoid neoplasia between 1986 and 1997 in New South Wales and Queensland. Immuno-phenotyping was by an immunoperoxidase method utilising species cross-reactive antibodies raised against human lymphocytes and an antibody raised against koala IgG. Cases were classified according to organs and tissues affected and the morphological features of neoplastic cells.
Results Twenty-six (51%) of the cases were of the T cell immunophenotype, 12 (24%) were of B cell immunopheno-type and 13 (25%) did not stain. The age and sex of koalas did not correlate with immunophenotype (P = 0.686 and P = 1.000, respectively). Thirty-two cases were leukaemic and 36 had multiple organ involvement, probably reflecting presenta tion of koalas at advanced stages of disease. Abdominal tissue involvement was most common (44 cases), followed by nodal (32), atypical (21) and cervicomediastinal (14). The T cell immunophenotype was over-represented among the leukaemic cases (P = 0.013). Generally, the T cell immunophenotype predominated except for many affected atypical tissues. Neoplastic cells were mostly of medium nuclear size with round to oval nuclei. No correlations were found for cell morphology, mitotic index and immunopheno-type.
Conclusion The prognostic value of an immunopheno-typic, anatomical and morphological basis for the classifica tion of lymphoid neoplasia in the koala currently is limited by the need to detect these neoplasms at an early age, the requirement for freshly fixed tissues and the restricted range of available cross-reacting antibodies. 相似文献
Methods Routine necropsies were performed on 51 koalas with suspected lymphoid neoplasia between 1986 and 1997 in New South Wales and Queensland. Immuno-phenotyping was by an immunoperoxidase method utilising species cross-reactive antibodies raised against human lymphocytes and an antibody raised against koala IgG. Cases were classified according to organs and tissues affected and the morphological features of neoplastic cells.
Results Twenty-six (51%) of the cases were of the T cell immunophenotype, 12 (24%) were of B cell immunopheno-type and 13 (25%) did not stain. The age and sex of koalas did not correlate with immunophenotype (P = 0.686 and P = 1.000, respectively). Thirty-two cases were leukaemic and 36 had multiple organ involvement, probably reflecting presenta tion of koalas at advanced stages of disease. Abdominal tissue involvement was most common (44 cases), followed by nodal (32), atypical (21) and cervicomediastinal (14). The T cell immunophenotype was over-represented among the leukaemic cases (P = 0.013). Generally, the T cell immunophenotype predominated except for many affected atypical tissues. Neoplastic cells were mostly of medium nuclear size with round to oval nuclei. No correlations were found for cell morphology, mitotic index and immunopheno-type.
Conclusion The prognostic value of an immunopheno-typic, anatomical and morphological basis for the classifica tion of lymphoid neoplasia in the koala currently is limited by the need to detect these neoplasms at an early age, the requirement for freshly fixed tissues and the restricted range of available cross-reacting antibodies. 相似文献
83.
84.
The occurrence of equine arteritis virus in Australia 总被引:2,自引:0,他引:2
This paper reports the first isolation of equine arteritis virus (EAV) in Australia and serological evidence of exposure to EAV in Australian horses. Twelve Standardbred stallions imported from North America were found to shed EAV in semen. One hundred and seven stallions were tested for serum antibodies to EAV and 73% of Standardbred stallions tested were seropositive as compared to 8% of Thoroughbred stallions. Serum antibody was detected in 71% of Standardbred mares, 6% of Standardbred racehorses and 1% of Thoroughbred mares and racehorses. Examination of stored serums demonstrated that EAV had been present in Australia since at least 1975. 相似文献
85.
Objective To review the breed, age, gender, clinical and laboratory findings, treatment and outcome of horses with caecal disease presented to a referral centre. Design Retrospective study of 96 cases. Procedure The breed, age, and gender of the study population were compared with the corresponding hospital population for the same period. The means (± SD) for clinical and laboratory findings were recorded for each caecal disorder. Treatment was categorised as medical or surgical, and outcome was recorded. Results Caecal diseases included impaction (40% of total cases), rupture associated with concurrent unrelated disease (13%), rupture with parturition (9%), rupture with no associated disease (5%), infarction (11%), torsion (9%), abscess or adhesion (7%), tumour (3%), and miscellaneous conditions (3%). The breed or gender of affected horses did not differ from the hospital population, although horses > 15 years were more frequently represented (P < 0.05). This age group was specifically more predisposed to caecal impaction (P < 0.05), as were Arabian, Morgan, and Appaloosa breeds (P < 0.05). In horses with caecal impaction transrectal examination was the most useful diagnostic procedure; 90% of affected horses treated medically were discharged while horses treated by typhlotomy alone, or typhlotomy and blind end ileocolostomy, had survival rates to discharge of 71% and 86%, respectively. Horses with caecal rupture associated with concurrent un-related disease showed no signs of impending rupture; all were receiving phenylbutazone, all were euthanased, and 50% had caecal ulceration at necropsy. Of horses with caecal rupture with parturition 56% had prior dystocia; in two-thirds the site of rupture was the ileocaecal junction and all were euthanased. Horses with caecal rupture with no associated disease died or were euthanased; rupture was idiopathic. Horses with caecal infarction usually had signs of abdominal pain and abdominal fluid changes consistent with peritonitis; transrectal examination was nonspecific, and typhlectomy was successful in seven of eight horses. Horses with caecal torsion had signs of severe, acute abdominal pain and typhlectomy was successful in three of five horses. Diagnosis of caecal adhesion or abscess was assisted by transrectal palpation in two of seven horses and surgical treatment was successful in two of five horses. A caecal tumour was diagnosed in three horses aged 20 years or older that presented with chronic weight loss. Other caecal diseases were uncommon. Conclusion Caecal disease is uncommon in equids but some specific features of the history and physical findings can alert the veterinarian to the possibility of caecal involvement in horses with gastrointestinal dysfunction. Medical or surgical therapy can be effective in horses where caecal rupture has not occurred. 相似文献
86.
Physiological Responses of Rainbow Trout Oncorhynchus mykiss to Crowding and Anesthesia with AQUI-S™
Glen W. Davidson Peter S. Davie Graham Young Reece T. Fowler 《Journal of the World Aquaculture Society》2000,31(1):105-114
Abstract.— Following exposure to the anesthetic AQUI-S™, plasma cortisol concentration in immature rainbow trout was measured as (mean) 293 ± 48 ng/ mL, which was significantly ( P > 0.05) higher than the mean concentration in resting fish. Cortisol concentrations remained significantly ( P > 0.05) elevated for at least 24 h after treatment. This was accompanied by a significant increase and decrease in hematocrit and plasma potassium, respectively. These perturbations continued for at least 48 h following recovery from anesthesia. Plasma concentrations of total protein and sodium remained unchanged following anesthesia with AQUI-S™. Crowding stress is commonly encountered by fish during manipulation in aquaculture situations. Anesthetising fish prior to, and during, manipulation may reduce the associated stress. Changes in cortisol values resulting from crowding (30 min; 0.1 kg/L) during anesthesia with AQUI-S™ were not appreciably different from those in fish crowded without anesthesia. Thus, anesthesia with AQUI-S™ at the recommended dose of 17 mg/L did not appear to be effective for alleviating the stress of crowding under the conditions of our experiments. 相似文献
87.
Objective
To assess students' perceptions of subject-based problem-based learning in the fourth year of the veterinary science course at the University of Queensland.
Design
A questionnaire-based study.
Procedure
Subject-based problem-based learning was introduced into parts of two fourth year subjects in a 5-year veterinary science course. The problem-based learning exercise used modified clinical cases and was computer-assisted. Students worked in groups of two to four, and small group discussion sessions were tutorless. Lectures were replaced by large group discussion and feedback sessions, led by the teacher, with approximately 85 students.
Results
There was a significant increase in the percentage of students who strongly agreed that they had better understanding of the subject, and had learned to apply principles from this class in new situations. The only consistent criticism by students was directed at the extra time required compared to traditional lecture-based subjects.
Conclusion
Students' perceptions of the learning outcome were very favourable for problem-based learning when compared to the lecture-based subject. 相似文献
To assess students' perceptions of subject-based problem-based learning in the fourth year of the veterinary science course at the University of Queensland.
Design
A questionnaire-based study.
Procedure
Subject-based problem-based learning was introduced into parts of two fourth year subjects in a 5-year veterinary science course. The problem-based learning exercise used modified clinical cases and was computer-assisted. Students worked in groups of two to four, and small group discussion sessions were tutorless. Lectures were replaced by large group discussion and feedback sessions, led by the teacher, with approximately 85 students.
Results
There was a significant increase in the percentage of students who strongly agreed that they had better understanding of the subject, and had learned to apply principles from this class in new situations. The only consistent criticism by students was directed at the extra time required compared to traditional lecture-based subjects.
Conclusion
Students' perceptions of the learning outcome were very favourable for problem-based learning when compared to the lecture-based subject. 相似文献
88.
The pathogenesis of velogenic Newcastle disease virus infection of chickens of different ages and different levels of immunity 总被引:2,自引:0,他引:2
Chickens of 7 weeks or 20 weeks of age were divided into three groups according to their antibody status (high, low, absent) and were infected with a velogenic viscerotropic Newcastle disease virus. To follow patterns of viral replication, birds were necropsied at regular intervals up to 22 days and organs were sampled from each bird. In non-immune birds, virus could be isolated from all organs examined. In birds with antibody, virus was most frequently isolated from the proventriculus, cecal tonsil, bursa, and brain. However, because no one organ could be recommended for all situations, all four should be sampled for field diagnosis. In immune birds, although clinical signs were either mild or absent, widespread virus replication occurred up to 19 days post-challenge. 相似文献
89.
R D Zenoble R J Kemppainen D W Young J W Carpenter 《Journal of the American Veterinary Medical Association》1985,187(11):1119-1120
The effect of ACTH on plasma corticosterone and cortisol was determined in 12 eagles (Haliaeetus leucocephalus) and in 6 Andean condors (Vultur gryphus). In all raptors, the concentration of plasma corticosterone was substantially greater than that of cortisol. After ACTH administration, the eagles had a marked increase (P less than 0.001) in plasma corticosterone concentrations, but not in plasma cortisol. Administration of saline solution did not induce increased plasma corticosterone concentrations in the eagles. The condors had a smaller increase (P less than 0.002) in plasma corticosterone concentrations after ACTH administration, as compared with that of the eagles. However, administration of saline solution in 2 condors resulted in an increase in corticosterone similar to the increase after ACTH administration. In the condor, a stress-related release of endogenous ACTH may have an effect similar to that induced by exogenously administered ACTH. Plasma cortisol concentrations did not increase significantly after administration of ACTH or saline solution in either raptor species. 相似文献
90.
Cardiorespiratory responses to electrical stimulation of the buccal mucosa in ponies 总被引:1,自引:0,他引:1
S S Young 《Research in veterinary science》1990,49(3):268-274
The cardiovascular and respiratory responses to electrical stimulation of the buccal mucosa under general anaesthesia in ponies were measured in order to provide some insight into the cardiorespiratory effects of anaesthesia in equidae. This knowledge may be useful for reducing morbidity during clinical anaesthesia in horses. Anaesthesia was induced with intravenous thiopentone and maintained with 1.3 per cent inspired halothane in oxygen. Arterial blood pressure, heart rate, minute volume, tidal volume, respiratory rate, arterial blood gas tensions and clinical signs of anaesthetic depth were recorded while the buccal mucous membrane was stimulated electrically. A rise in arterial blood pressure was the most consistent response detected along with clinical signs. The response of individual animals varied considerably. Alterations of respiratory pattern sometimes occurred during stimulation but there was no consistent pattern of change in any animal. 相似文献