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排序方式: 共有5124条查询结果,搜索用时 15 毫秒
61.
Carl D. Sammarco BVSc Joan Regan VMD Cynthia R. Ward VMD PhD James D. Buchanan DVM M Med Sci 《Veterinary radiology & ultrasound》1995,36(6):517-518
The Clinical, radiologic and echocardiographic findings in a one-year old dog with mild subvalvular aortic stenosis and aberrant caudal vena circulation are described. Aberrant systemic venous return to the right side of the heart usually has little clinical significance, but the unusual features in survey radiographs, contrast angiograms and contrast echocardiograms constitute the reasons for this report. 相似文献
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64.
Wilson RT 《Tropical animal health and production》2011,43(7):1419-1425
The six countries comprising the Horn of Africa are Djibouti, Eritrea, Ethiopia, Kenya, Sudan and Somalia. Together, they
cover an area of just under 5 million square kilometres and support a human population of 17.7 million at an average density
of 38.15 people per square kilometre (although in the purely pastoral areas population density is probably of the order of
15–16 people per square kilometre). The Horn is a major repository of domestic animal biodiversity and genetic resources and
is home to 15 million one-humped camels, 110 million cattle, 94 million goats and 102 million sheep. A list of 72 sheep “breeds”
of which 23 can be considered fat-tailed or fat-rumped has been compiled for the area, although many of these are merely subtypes
of a larger grouping and several are not native to the Horn. This paper provides information, where such is available, on
the distribution, numbers and production parameters of the fat-tailed and fat-rumped sheep that occupy the Horn. 相似文献
65.
Perkins JD Meighan H Windley Z Troester S Piercy R Schumacher J 《Veterinary surgery : VS》2011,40(3):305-310
Objective: To determine whether ventriculocordectomy (VCE) performed before prosthetic laryngoplasty (PL) results in increased rima glottidis size compared with PL alone. Study Design: Experimental study. Animals: Equine cadaver larynges (n=13). Methods: Right arytenoid cartilages were maximally abducted using a standard PL technique. Standard PLs were then performed on the left side and the force required to maximally abduct the left arytenoid cartilage recorded (Fmax). Photographs were taken of the rima glottidis at zero force and at five equal levels of force up to Fmax. The force applied was released, left VCE performed, and photographs repeated. Arytenoid left:right angle quotients (LRQ) and glottic cross‐sectional area ratios (CSAR) were calculated at each force level in each condition (PL and VCE‐PL). Results: Mean LRQ and CSAR for both PL and VCE‐PL increased with increasing force, initially rapidly before plateauing at ~50% of Fmax. LRQ and CSAR were significantly greater for VCE‐PL than for PL (P<.001). When VCE was performed before PL, 12% less force was required to achieve an LRQ of 0.8, and 45% less for a CSAR of 0.8. Conclusions: In vitro, VCE performed before PL enables the arytenoid cartilage to be abducted to a greater degree for a given PL suture force. 相似文献
66.
Jean K. Reichle DVM MS Richard A. Peterson II DVM Mary B. Mahaffey DVM MS Curtis G. Schelling VMD MS Paul Y. Barthez DVM PHD 《Veterinary radiology & ultrasound》2003,44(4):433-437
Four dogs with ureteral fibroepithelial polyps, ranging from 9-12 years of age, are presented in this report. The patients presented with urinary incontinence, urinary tract infection, and/or polydypsia and pollakiuria. All dogs were intact at the time of diagnosis or for the majority of their lives and three were male. Various diagnostic procedures were performed including ultrasonography, contrast radiography, and nuclear scintigraphy. Not all procedures were performed in all patients. Findings included ureteral dilation proximal to the level of an intraluminal mass and ipsilateral hydronephrosis. Unilateral ureteronephrectomy was performed in three dogs with masses in the proximal ureter; ureteral resection and anastamosis was performed in the remaining patient with a mass located in the distal ureter. The same pathologist (RAP) reviewed all four lesions. The lesions appeared polypoid and were attached to the ureteral wall by a thin stalk. Histopathologically, they contained a superficial layer of well-differentiated transitional epithelial cells overlying a prominent fibrovascular stroma with a mild (three dogs) or marked (one dog) degree of lymphoplasmacytic inflammation. This disease may represent a benign neoplasm or a chronic inflammatory reaction and has a good prognosis with surgical removal. Its histopathological characteristics, higher incidence in males, and location more commonly within the upper third of the ureter is remarkably similar to the disease in humans. 相似文献
67.
Carlos R Sanchez Suzan Murray Richard J Montali Lucy H Spelman 《Journal of zoo and wildlife medicine》2004,35(3):397-399
A 37-yr-old female Asian elephant (Elephas maximus) presented with anorexia, restlessness, and dark-colored urine. Urinalyses showed hematuria, leukocyturia, isosthenuria, proteinuria, granular casts, and no calcium oxalate crystals. Bloodwork revealed azotemia. Urine culture revealed a pure growth of Streptococcus zooepidemicus resistant to sulfamethoxazole-trimethoprim but susceptible to cephalosporins. A presumptive diagnosis of pyelonephritis was made based on bloodwork, urinalysis, and urine culture. The animal was treated with intravenous ceftiofur, and intravenous and per rectum fluids were given for hydration. The elephant's attitude and appetite returned to normal, the abnormal blood parameters resolved, and urinary calcium oxalate crystals reappeared after treatment, supporting presumptive diagnosis. Follow-up ultrasonography revealed an abnormal outline of both kidneys with parenchymal hyperechogenicity and multiple uterine leiomyomas. 相似文献
68.
Mycobacterium avium subsp. paratuberculosis (Mptb) causes Johne's disease in ruminants. Disease control programmes aim to break the faecal-oral cow-calf transmission cycle through hygienic calf rearing and removal of affected cows from the herd, but these programmes do not take account of the potential for congenital infection. The aims of this study were to critically review research on in utero infection, determine the prevalence of fetal infection in cattle through meta-analysis and estimate the incidence of calves infected via the in utero route. About 9% (95% confidence limits 6-14%) of fetuses from subclinically infected cows and 39% (20-60%) from clinically affected cows were infected with Mptb (P<0.001). These are underestimates for methodological reasons. The estimated incidence of calf infection derived via the in utero route depends on within-herd prevalence and the ratio of sub-clinical to clinical cases among infected cows. Assuming 80:20 for the latter, estimates of incidence were in the range 0.44-1.2 infected calves per 100 cows per annum in herds with within-herd prevalence of 5%, and 3.5-9.3 calves in herds with 40% prevalence. These estimates were not markedly sensitive to the value chosen for the proportion of clinical cases. In utero transmission of Mptb could retard the success of disease control programmes if the opportunities for post natal transmission via colostrum/milk and environmental contamination were able to be controlled. The consequences of fetal infection for the calves so infected are discussed in the context of diagnosis and vaccination together with recommendations for future research. 相似文献
69.
70.
The objectives of the current study were to estimate the sensitivity and specificity of three real-time polymerase chain reaction (PCR) tests for diagnosis of feline immunodeficiency virus (FIV) infection in domestic cats, both individually and when interpreted in series with one of two serological tests, separately in populations of cats at low and high risk of being infected with FIV. One PCR test targeted the pol gene and two targeted the gag gene of FIV. For comparison, sensitivities and specificities of the individual serological tests (IDEXX SNAP(?) test and AGEN Simplify(?) test) were also estimated. The study populations consisted of domestic cats thought to be not vaccinated against FIV. Low-risk (males aged 4 years or less and females; n=128) and high-risk (males over 4 years; n=128) cats were selected from those where blood samples were submitted to a commercial clinical pathology service. Bayesian latent class models were used to obtain posterior probability distributions for sensitivity and specificity for each test, based on prior distributions obtained from three experts. Medians of the posterior sensitivity distributions for the PCR tests based on the pol gene and two regions of the gag gene tests ranged from 0.85 to 0.89, compared to 0.89-0.97 for the two serological tests. The medians of posterior specificity distributions for these PCR tests were 0.94-0.96, and 0.95-0.97 for the serological tests. In contrast, the PCR based on one region of the gag gene had lower median sensitivity. Sensitivities of combinations of these serological and PCR tests interpreted in series were low; medians of posterior sensitivity distributions ranged from 0.75 to 0.83. Relative to the low-risk population, median sensitivities in the high-risk population were lower for all tests other than the AGEN Simplify(?) test; specificities were similar in both populations. We conclude that the sensitivities of the two PCR tests based on the pol gene and two regions of the gag gene, respectively, in non-vaccinated cats are probably lower than the sensitivities of the two serological tests we assessed. We do not recommend screening cats whose FIV vaccination status is uncertain with one of these serological tests and then testing positives with one of these PCR tests because in non-vaccinates, the sensitivities of combinations of these serological and PCR tests interpreted in series are low. Assessment of the validity of these PCR assays in FIV-vaccinated cats is required. 相似文献