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排序方式: 共有951条查询结果,搜索用时 562 毫秒
81.
Sykes JE Bailiff NL Ball LM Foreman O George JW Fry MM 《Journal of the American Veterinary Medical Association》2004,224(12):1946-51, 1930-1
A 3-year-old sexually intact male Bull Mastiff underwent splenectomy for splenic thrombosis; prior to and after splenectomy, multiple blood transfusions were administered. Two weeks after the procedure, T-cell lymphoproliferative disease was diagnosed. Treatment with prednisone and chlorambucil was initiated, and 2 weeks later, cytologic examination of a blood smear revealed small (0.3 microm), coccoid basophilic bodies on the surface of approximately 70% of the RBCs. Morphologically, these resembled "Candidatus Mycoplasma haemominutum." A polymerase chain reaction assay was used to amplify a partial 16S rRNA sequence in blood obtained from the dog; the product was sequenced and compared with 16S rRNA gene sequences of other hemotropic mycoplasmas. The sequence was 98% homologous to that of "Candidatus M haemominutum", but only 77% homologous to that of M haemocanis and M haemofelis. 相似文献
82.
83.
Johnson W Roof M Vaughn E Christopher-Hennings J Johnson CR Murtaugh MP 《Veterinary immunology and immunopathology》2004,102(3):233-247
Although much research has been performed on porcine reproductive and respiratory syndrome virus (PRRSV), little quantitative information is available on the relationships between virulence and in vivo virus replication, among isolates recovered at different times in the history of PRRS, or the relative levels of virulence associated with individual virus isolates. In this study, the in vivo growth properties of virulent field isolates and attenuated PRRSV isolates were compared. The results show that virulent PRRSV isolates exhibit longer and more elevated levels of viremia, induce faster and more intense humoral immune responses, negatively affect body weight gain, induce higher death rates, and cause more severe clinical signs in a respiratory disease model. We found that the more virulent field isolates grew to significantly higher levels in pigs than did cell-culture adapted isolates. We concluded that the pathogenic consequences and immunological responses of pigs to PRRSV are directly related to viral load in acute infection as reflected in viral titers in blood. 相似文献
84.
85.
OBJECTIVE: To determine the association between limb conformation scores in gilts and retention through the second parity. ANIMALS: 961 gilts. PROCEDURE: Gilts were monitored for 1 year. Baseline data recorded were conformation scores for the forelimbs and hind limbs and backfat thickness. Primary outcome was time to removal from a herd, and the secondary outcome was time to removal as a result of lameness. RESULTS: 662 of 961 (68.89%) females remained in herds through the second parity, whereas 299 (31.11%) were removed before the second parity. Survival time for females on the basis of conformation scores for the forelimbs and hind limbs differed significantly for total sow removals and removals as a result of lameness. Females with poor conformation scores for the hind limbs had an increased risk of being removed, compared with risk for females with better conformation scores. Risk of removal specifically as a result of lameness increased as conformation score for the hind limbs became poorer. Proportion of the total population that was removed and could be attributed to undesirable limb conformation was 16.13% for forelimbs and 12.90% for hind limbs. CONCLUSIONS AND CLINICAL RELEVANCE: Females with undesirable conformation were removed earlier than females with desirable conformation. This was particularly true for females with low conformation scores for the hind limbs. Selection of gilts on the basis of limb conformation may result in reduced attrition of females and improved performance of herds over time. 相似文献
86.
Sykes JE Kittleson MD Chomel BB Macdonald KA Pesavento PA 《Journal of the American Veterinary Medical Association》2006,228(11):1735-1747
OBJECTIVES: To evaluate clinical, laboratory, and necropsy findings in dogs with infective endocarditis (IE). DESIGN: Retrospective case series. ANIMALS: 71 dogs with possible or definite IE. PROCEDURES: Medical records were reviewed for signalment, clinical features, and results of clinicopathologic testing and diagnostic imaging. Yearly incidence and the effect of variables on survival were determined by use of survival curve analysis. RESULTS: The overall incidence of IE was 0.05%. Most affected dogs were of large breeds, and > 75% were older than 5 years. The aortic valve was affected in 36 of the 71 (51%) dogs, and the mitral valve was affected in 59%. Lameness caused by immune-mediated polyarthritis, septic arthritis, or peripheral arterial thromboembolism was observed in 53% of the dogs. Neurologic complications were diagnosed in 17 of 71 (24%) dogs. Thromboembolic disease was suspected in 31 of 71 (44%) of dogs. The mortality rate associated with IE was 56%, and median survival time was 54 days. Factors negatively associated with survival included thrombocytopenia, high serum creatinine concentration, renal complications, and thromboembolic complications. CONCLUSIONS AND CLINICAL RELEVANCE: A diagnosis of IE should be suspected in dogs with fever, systolic or diastolic murmur, and locomotor problems. Dogs with thrombocytopenia, high serum creatinine concentration, thromboembolism, or renal complications may have a shorter survival time. 相似文献
87.
Turrel JM Farrelly J Page RL McEntee MC 《Journal of the American Veterinary Medical Association》2006,228(6):898-901
OBJECTIVE: To determine the efficacy of strontium 90 beta irradiation in the management of cutaneous mast cell tumors (CMCTs) in cats. STUDY DESIGN: Retrospective case series. ANIMALS: 35 client-owned cats with CMCTs. PROCEDURE: Medical records of cats with CMCTs in which tumors were radiated by use of a strontium 90 ophthalmic applicator from 1992 to 2002 were reviewed. Cats were included if CMCT was diagnosed, there were no other sites of MCT involvement at the time of treatment, and records contained adequate follow-up information to permit retrospective assessment of local tumor control. RESULTS: 54 tumors in 35 cats were treated with a median dose of 135 Gy of strontium 90 beta irradiation, resulting in local tumor control in 53 of 54 (98%) tumors with a median follow-up time of 783 days after treatment. Median survival time was 1,075 days. Adverse effects of treatment appeared to be infrequent and of mild severity. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that strontium 90 beta irradiation resulted in long-term tumor control and should be considered an effective alternative to surgical resection in management of CMCTs in cats. 相似文献
88.
Qiu J 《Science (New York, N.Y.)》2012,336(6079):291
89.
90.
Johanna Lindahl Anne-Marie Dalin Gesa Stuhtmann Jane M Morrell 《Acta veterinaria Scandinavica》2012,54(1):40