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Following a workshop on equine protozoal myeloencephalitis (EPM) convened at the Veterinary Medical Forum of the American College of Veterinary Internal Medicine in 1988, this survey of EPM in North America was developed. It is based upon 364 histologically confirmed case records from California, Florida, Illinois, Kentucky, New York, Ohio, Oklahoma, Ontario, Pennsylvania, and Texas up to 1988. The highest rate of infection was found in young Thoroughbred, Standardbred, and quarter horses. Differences in geographic location, sex, and month (season) of infection were not discernible. This report, the first comprehensive survey of EPM in North America, is intended to serve as a basis for evaluating future changes in prevalence and spread of EPM.  相似文献   
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OBJECTIVE: To determine outcome associated with intramural ureteral ectopia treated with 1 of 2 surgical techniques (neoureterostomy with ligation of the distal ureteral segment vs neoureterostomy with resection of the distal ureteral segment) and compare results of these 2 techniques in dogs. DESIGN: Multicenter retrospective case series. ANIMALS: 36 dogs (15 treated with the ligation technique and 21 treated with the resection technique). PROCEDURES: Information was obtained from medical records. Long-term follow-up information was obtained by owner questionnaire. RESULTS: 15 of 21 (71%) dogs in the resection group and 7 of 14 (50%) dogs in the ligation group still had urinary incontinence after surgery. Three of 20 (15%) dogs in the resection group and 4 of 14 (29%) dogs in the ligation group reportedly had multiple episodes of urinary tract infection following surgery. The outcome of surgery was judged to be excellent by the owners of 10 of 18 (56%) dogs in the resection group and 9 of 14 (64%) dogs in the ligation group. No significant differences were found between surgery treatment groups. CONCLUSIONS AND CLINICAL RELEVANCE: Results of the present study suggest that although most owners of dogs that undergo surgery for treatment of intramural ureteral ectopia consider the outcome of surgery to be excellent, substantial proportions of dogs will continue to have urinary incontinence and recurrent urinary tract infections after surgery. Findings do not provide any support to the hypothesis that the resection technique is superior to the ligation technique for management of dogs with intramural ureteral ectopia.  相似文献   
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The aim of the present research is to study the effect of pH values on the sperm rheotaxis properties. Semen collected from bulls was diluted with SOF medium (1:10). pH of the medium was adjusted using a digital pH meter to the following pH values: 6.0, 6.2, 6.4, 6.4, 6.8, 7.0. All kinetic parameters of sperm (n = 3,385) were determined through a computer‐assisted sperm analysis (CASA) system using microfluidic devices with controlled flow velocity. The following parameters were determined: total motility (TM%), positive rheotaxis (PR%), straightline velocity (VSL, μm/s), average path velocity (VAP, μm/s), linearity (LIN, as VSL/VCL, %), beat cross‐frequency (BCF, Hz) and curvilinear velocity (VCL, μm/s). Nitric oxide, calcium and potassium were estimated in semen at different pH values. To confirm the effect of nitric oxide and K+, we used sodium nitroprusside (an NO donor) and KCL as (a K+ donor) to see their effect on sperm PR%. The results showed no difference in TM% at pH (6–7). The PR% was the lowest at pH 6 and 7. The best parameters for the PR% were at pH 6.4–6.6. The concentration of Ca+2 did not change at different pH values. The mean NO values decreased with the increase of pH; however, the mean values of K+ increased with the increase of pH. Addition of high concentration of NO and K+ to the semen media at fixed pH level had a negative effect on TM% and PR%. In conclusion, the bull sperm had the best rheotaxis properties at pH 6.4–6.6 and sensitive to the change of seminal NO and K+.  相似文献   
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