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Gareth H. Spurlock DVM MS Shauna L. Spurlock DVM MS George A. Parker DVM 《Veterinary radiology & ultrasound》1989,30(4):184-188
Collagenase-induced lesions of the superficial digital flexor tendon were monitored using diagnostic ultrasound and subsequently compared with gross and microscopic findings. The postinjury sonograms demonstrated hypoechoic or anechoic areas corresponding to areas of hemorrhage and necrosis. The size of the lesion increased and the echogenicity decreased with increasing units of collagenase injected into the tendon. As postinjury time increased, echogenicity increased, which corresponded to fibrous-tissue invasion and collagen deposition. The extent of tendon injury produced correlated with the amount of collagenase injected into the tendon. Diagnostic ultrasound is useful in evaluating injury and healing in collagenase— induced tendinitis. 相似文献
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S Urcelay D W Hird E M Huffman K Parker T B Farver 《Canadian journal of veterinary research》1984,48(4):394-401
To determine risk factors for development of diarrhea in litters of preweaned piglets, data were analyzed from records of 4,397 litters of swine farrowed on a central California ranch 1978-1982. Sixty-four percent of litters were treated for diarrhea. Statistical analysis by multiple logistic regression showed that litters born to young sows (parity less than or equal to 2) were 1.7 times more likely to develop diarrhea before weaning than were litters born to older sows (parity greater than or equal to 3) and that litters born on one end of farrowing barns were 1.3 times more likely to develop diarrhea than were litters born in the other end. The association of diarrhea with other variables--dam breed, sire, gestation group, gestation length, size of litter, number of mummies, runts or stillbirths per litter, farrowing barn of birth or day of the week farrowed--was weak or nonexistent (P greater than 0.01). 相似文献
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Nephrotoxicity of sodium arsenate in dogs 总被引:1,自引:0,他引:1
H Tsukamoto H R Parker D H Gribble A Mariassy S A Peoples 《American journal of veterinary research》1983,44(12):2324-2330
Nephrotoxicity of sodium arsenate was evaluated in dogs to determine the pathophysiologic basis for renal lesions caused by this heavy metal. Examination of biopsy specimens indicated that the low dose of the As salt (0.73 mg/kg of body weight) produced histologic changes consisting of mild degeneration and vacuolation of renal tubular epithelium. Vacuolation involved mainly the ascending thick portion of the nephron. Clinical pathologic changes were not demonstrable at this dosage level according to glomerular filtration rate (creatinine clearance), fractional reabsorption of sodium, potassium, and chloride; plasma osmolar and free water clearance; and urinalysis. The medium dose (7.33 mg/kg) resulted in alterations determined by urinalysis, but did not markedly affect other clinical pathologic measurements. Histopathologic changes were equal to or greater than those seen with the low dose. Tubular necrosis was observed in the cortical portion of the nephron and the ascending thick limb. The high dose (14.66 mg/kg) consistently produced marked changes in all parameters evaluated. Clinical pathologic alterations were compatible with acute tubular necrosis involving all segments of the nephron. Histologically, moderate glomerular sclerosis and severe tubular necrosis were observed. During recovery from the high dose of As, a gradual compensatory healing process was observed that was evident in all clinical pathologic parameters and was confirmed from sequential renal biopsy specimens. 相似文献
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Abomasal fistulas in dairy cows 总被引:1,自引:0,他引:1
Abomasal fistulas were corrected surgically in 9 adult Holstein cows. Six cows had a history of right paramedian abomasopexy (RPA), and 2 cows had had a percutaneous abomasopexy using the blind-stitch technique (BSA). Fistulas developed from 2 weeks to 12 months after the RPA or BSA. In 1 cow, history was not available beyond 2 years, and no surgery had been performed in that time. All fistulas were in the right paramedian area and were draining blood and/or ingesta from necrotic abomasal tissue (8 cows) or ruminal tissue (1 cow). Surgery was performed immediately in cows with consistent hemorrhage from the fistulated tissue (4 cows). Surgery was delayed to reduce rumen contents if bleeding was absent or considered negligible (4 cows) or to stabilize the patient (1 cow). General anesthesia was used in 7 cows, local anesthesia in 2 cows. Outcome following the fistula resection was successful in the 7 cows discharged from the clinic. The occurrence of abomasal fistulation is probably related to nonabsorbable sutures penetrating the abomasal lumen during the abomasopexy procedure resulting in infection of the incision or body wall. 相似文献
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