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91.
Surgical Treatment of Priapism in a Stallion   总被引:1,自引:0,他引:1  
Priapism occurred in a stallion after the administration of acetylpromazine. When conservative measures failed, the corpus cavernosum penis (CCP) was drained and irrigated, and a vascular shunt between the erectile bodies was created. Subsidence of erection resulted, but subsequently, the stallion was unable to retract or erect the penis. The stallion was castrated and the penis was surgically retracted into the sheath.  相似文献   
92.
Articular cartilage exposure and immediate postoperative stability provided by three medial surgical approaches in canine cadaver elbows were compared. The approaches evaluated were a desmotomy of the medial collateral ligament (DMCL) that included a tenotomy of the pronator teres muscle, a longitudinal myotomy of the flexor carpi radialis (MFCR), and an osteotomy of the medial epicondyle (OME). Nondestructive biomechanical testing was performed before the surgical approach and repeated after surgery. The stiffness at 13 valgus deviation of the elbow and energy absorption up to 13 valgus deviation of the elbow were determined from the pre-operative and postoperative torque-rotation curves. The perimeters of the ulnar and humeral articular cartilage that were visualized through the approach were scored with a dental pick. Latex casts were made of articular surfaces of the elbow. The humeral and ulnar articular exposures were determined by computerized planimetric analysis of latex cast photocopies. The humeral cartilage exposure of the OME approach was significantly greater than either the MFCR or DMCL approaches. The DMCL approach provided a significantly greater humeral cartilage exposure than the MFCR approach. All three approaches provided statistically similar percentages of ulnar cartilage exposure. The stiffness and energy absorption of the OME and MFCR approaches were similar and significantly greater than the DMCL approach. The OME approach provided the best combination of exposure and immediate postoperative stability.  相似文献   
93.
94.
Clenbuterol, a bronchospasmolytic agent (β2 agonist) was studied in terms of its hemodynamic and airflow response in eight, healthy horses. Four animals were instrumented to record intrapleural pressure and air flow, these were used to compute pulmonary resistance, peak flow rates, and tidal volumes. Four animals were instrumented to record pulmonary arterial pressure, carotid arterial pressure, cardiac output, and arterial gas tensions. After control values were recorded, clenbuterol (0.8 μg/kg) was intravenously administered to each horse in each experiment group.
Following clenbuterol administration, non-elastic resistance of the lung or pulmonary resistance significantly decreased, 33.6% reduction at 10 min post-clenbuterol. Pulmonary resistance remained lowered during the entire procedure and showed no tendency of returning toward control values by 3 h post-clenbuterol. Within 30 sec following clenbuterol injection carotid arterial pressure decreased (mean pressure decrease 28.2%). Accompanying the change in arterial pressure, the heart rate drastically increased, 99.0%. Both changes were transient and returned to control ranges within 2 min.
Clenbuterol appears to be effective in reducing non-elastic resistance of the lung, however intravenous administration to an animal with pre-existing cardiovascular or cardiopulmonary disease should be avoided.  相似文献   
95.
Renal dysplasia is a hereditary disease characterized by abnormal differentiation of renal tissue. The ultrasonographic appearance of dysplastic canine kidneys has been reported in the late stage of the disease where inflammatory and degenerative changes are already present and the dogs are in chronic renal failure. In this study, we describe the ultrasonographic appearance of the kidneys of five related Cairn Terriers affected with renal dysplasia before the onset of clinical or laboratory evidence of renal failure. Common findings included poor corticomedullary definition and multifocal hyperechoic speckles in the renal medulla, or a diffusely hyperechoic medulla. Severity of ultrasonographic changes was related to the severity of histopathologic findings. The ability to detect dysplastic changes before clinical signs develop makes ultrasound a potentially useful screening method for canine renal dysplasia.  相似文献   
96.
Urethral extension was performed in 14 cows with clinical urovagina and infertility. Urovagina was corrected in nine cows (64%) and was reduced in the others. Formation of fistulas at the cranial end of the extension site was the most frequent complication (4 cows). In one cow, the urethral extension was not extended far enough caudally. Eleven cows (79%) returned to fertility after surgery. Severity of urine pooling, cranial displacement of the urethral orifice, and severe preoperative vaginitis may explain the failure of the urethral extension in some cows.  相似文献   
97.
Comment     
What follows is a comment on Noel D. Uri's “The Structure of Agricultural Unemployment in the United States,” published in Growth and Change in Summer 1989. Uri's reply appears after the comment.  相似文献   
98.
We report a case of complete rupture of the tendon of origin of the long digital extensor at the myotendinous junction, with concurrent ruptures of the posterior cruciate and lateral collateral ligaments in the stifle joint of a cat. Stabilization was accomplished by direct suturing of the long digital extensor injury, imbrication of the joint capsule and lateral retinacular fascia, and creation of a synthetic lateral collateral ligament  相似文献   
99.
In six horses, a 0.05% solution of chlorhexidine diacetate was used to lavage one tarsocrural joint; the contralateral control joint was lavaged with lactated Ringer's solution. Horses were evaluated daily for lameness. Synovial fluid samples were collected on days 1, 4, and 8 for determination of protein concentration, total and differential leukocyte counts, and mucin clot formation. After death on day 8, synovium and osteochondral samples were collected from the tarsocrural joints for examination of morphology and proteoglycan staining. Lavage with chlorhexidine solution caused lameness that was reduced but still evident at day 8. Synovial protein concentration was significantly increased by chlorhexidine lavage; the greatest increase occurred on day 1. Joint lavage increased synovial leukocyte counts on day 1, primarily by increasing polymorphonuclear (PMN) cell counts. Although total synovial leukocyte counts returned to normal by day 4, PMN cell counts remained elevated through day 8; PMN cell counts for chlorhexidine-lavaged joints were typically twice that of control joints. Chlorhexidine lavage caused synovial ulceration, inflammation, and abundant fibrin accumulation. Consistent differences in proteoglycan staining were not detected between control and chlorhexidine-lavaged joints. Joint lavage with 0.05% chlorhexidine diacetate, the lowest known bactericidal concentration, is not recommended for equine joints.  相似文献   
100.
Acidity in the soil surface and subsurface is of major concern in horticulture, cropping and pasture production systems in southern Australia. Broadcast applications of lime to the surface have proved to be ineffective in ameliorating subsurface acidity in the short term. Two calcium-saturated coal-derived organic products, an ‘oxi-product’ (OXPR) and an ‘oxi-fulvate’ (OXFU), were evaluated for use as liming materials with specific consideration given to amelioration of subsurface acidity. The effects of these two organic products and of lime on the chemical composition of the A1 and A2 horizons of an acid red podzol were investigated in leaching columns, 20 cm long. OXPR and OXFU supplying 80 or 160 g Ca m?2 were compared to 160 g Ca m?2 applied as CaCO3 and a control receiving no amendments. The effects of CaCO3 on exchangeable Al and pH were limited to the surface 2 cm. In contrast, the two organic amendments were effective in decreasing exchangeable Al and increasing pH and exchangeable Ca to depth, the extent being a function of amendment and rate applied. The formation of inorganic and organic complexes were assumed to be responsible for the movement of Al out of the column in the leachate, although significant quantities of Al were precipitated in the column. Significant linear regressions were observed between the ionic strength and Al in the leachate. Significant quantities of Mg and K were displaced by Ca and leached from the column; consequently, this loss must be considered against the benefits of decreased exchangeable Al when assessing fertility for plant production.  相似文献   
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