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91.
Despite the early notion that canine oral malignant melanoma is radioresistant, recent data suggest that external beam radiotherapy is effective in local tumor control. However, optimal fractionation schedules have not been established. The high rate of regional and distant metastasis is another problem that has hindered long-term control. The role of chemotherapy in the management of canine oral melanoma has also not been determined. In this study, data from 140 dogs irradiated at North Carolina State University were evaluated with the following objectives: (1) to compare the efficacy of three radiation therapy protocols (36 Gy, 9 Gy x 4 fractions; 30 Gy, 10 Gy x 3 fractions; or >45 Gy, 2-4 Gy x 12-19 fractions) for the treatment of dogs with oral malignant melanoma, (2) to identify any host or tumor factors influencing prognosis, and (3) to determine the impact of systemic chemotherapy on treatment outcome. Information regarding response to therapy, disease progression, and survival were determined from the medical records or from information obtained by telephone or mail survey. Relationships between host, tumor, and treatment variables and outcome measures (response, time to first event, and survival) were evaluated using Fisher's exact test (response) and the Cox regression model (time to first event and survival). The median time to first event for the 140 dogs was 5.0 months (95% C.I., 4-6 months) and the median survival was 7.0 months (95% C.I., 6-9 months). In the univariate analysis, the following variables were associated with increased time to first event and survival: (1) rostral tumor sublocation; (2) lack of bone lysis observed on skull imaging, and (3) microscopic tumor burden. In a multivariate analysis of 111 dogs with complete data for these variables, tumor sublocation, bone lysis, and tumor volume were identified as joint predictors of time to first event (p < .001, p < .001, and p = .04, respectively) and survival (p < .001, p < .001, and p = .05, respectively). There were no differences in response, time to first event and survival between the three radiation therapy protocols used. Systemic chemotherapy had no impact on the development of metastatic disease, time to first event, or survival, although the dosages used in this study were suboptimal. External beam radiation therapy is effective in local disease control of canine oral malignant melanoma; however, the optimal fractionation scheme has yet to be determined. The high metastatic rate observed with this disease and the inefficacy of systemic chemotherapy indicate that further investigation into novel therapies is warranted.  相似文献   
92.
This study assessed the effects of postoperative exercise and intra-articular polysulfated glycosaminoglycan (PSGAG) on the repair of osteochondral defects in the carpal joints of ponies. Eighteen ponies with normal carpi had osteochondral defects (mean dimensions 2.4 cm × 0.9 cm) created arthroscopically on the dorsal aspect of the distal articular surface of the radial carpal bone. The ponies were randomized (while balancing for age [range, 2 to 15 years; median, 5.0 years]) to two groups—nine ponies were exercised and nine were stall confined. Beginning at surgery, six ponies in each group received five weekly intra-articular injections of PSGAG (250 mg) in one joint and lactated Ringer's solution in the contralateral joint; the remaining three ponies in each group received lactated Ringer's solution in both joints. The incremental exercise schedule on a circular, rotating walker was begun six days after surgery and occurred twice daily, reaching a maximum of 0.7 miles of walking and 2.7 miles of trotting by the third postoperative month. The effects of treatment on the joint tissues were determined by weekly lameness examinations and measurement of the range of carpal joint motion, carpal radiographs at six and 17 weeks after surgery, synovial fluid analysis, and cytologic evaluation of alcohol-fixed synovial fluid specimens at weeks 1 through 4 and week 17, and histology of the synovial membrane. Ultrasound images of the carpi were acquired before operation and at weeks 1, 2, 4, 8, 10, 13, and 17. Ponies were euthanatized 17 weeks after surgery. Exercise, without medication, caused more lameness throughout the study compared with no exercise. Exercised, nonmedicated ponies had the greatest limitation to carpal flexion (more painful joints), and nonexercised, nonmedicated (control) ponies had the least limitation to flexion. Radiographic scores indicated that the exercised, nonmedicated ponies had significantly (p < .05) more signs of osteoarthritis than exercised, medicated and control ponies. Ultrasonographic measurements indicated that exercise, without medication, caused the greatest increase in combined measurement of the joint capsule thickness and synovial fluid accumulation at all postoperative times. Synovial lining cell numbers in the synovial fluid from exercised ponies were significantly (p < .05) higher than in nonexercised ponies at week 1, and this trend continued at weeks 4 and 17 (p < .1). There were significantly (p < .05) more morphologic abnormalities in the synovial lining cells from exercised than from nonexercised ponies at week 17. Medication with PSGAG enabled exercised carpal joints to be flexed significantly further from weeks 2 through 6 compared with nonmedicated joints. Medication significantly (p < .05) reduced the combined joint capsule and synovial fluid thickness at weeks 4, 8, and 13 compared with nonmedicated joints. On histologic examination, the synovial membrane matrix of exercised, medicated joints had significantly less chronic inflammatory changes than joints receiving other treatments. The authors concluded that this level of exercise was too intense when superimposed on large osteochondral defects in the carpus because it induced osteoarthritis. Polysutfated gtycosaminoglycan ameliorated the clinical signs of osteoarthritis in the exercised ponies. However, PSGAG was also associated with the formation of cartilage repair tissue that contained less type II relative to type I collagen compared with repair tissue from nonmedicated joints.  相似文献   
93.
OBJECTIVE: To measure the effects of transection of the accessory ligament of the superficial digital flexor (SDF) muscle (superior check desmotomy) on flexor tendon and suspensory ligament (SL) strain in vitro. STUDY DESIGN: In vitro experimental biomechanical investigation. ANIMALS USED: Ten equine cadaver forelimbs. METHODS: The effects of superior check desmotomy were determined using equine cadaver forelimbs secured in a servocontrolled hydraulic testing machine. Strain sensors were used to measure strain on the superficial and deep digital flexor tendons and SL, and a goniometer was used to measure joint angles when the limb was loaded at 890 N and 3,115 N before desmotomy, and at 3,115 N after desmotomy. RESULTS: Superior check desmotomy was associated with significantly increased strains on the SDF tendon and SL, and significant alterations in the angles of the metacarpophalangeal and carpal joints. CONCLUSIONS: The superior check ligament has an important role in maintaining joint angles and load distribution in the forelimb. Lengthening of the SDF musculotendinous unit after superior check desmotomy may be associated with increased strain on the SL. CLINICAL RELEVANCE: Transection of the accessory ligament of the SDF muscle may predispose horses to SL desmitis postoperatively.  相似文献   
94.
A retrospective analysis was conducted of all feline necropsies performed during a nine year period to identify cases of sever, acute, centrilobular (periacinar), hepatic necrosis (ACHN). After exclusion of cats with anemia, a series of seven cases of ACHN was identified. In addition, two similar cases were identified from tissue submitted for histopathology following, and eight had bile duct hyperplasia. Seven of the nine cats received diazepam prior to dath, and one received zolazepam. Of the seven cats that received diazepam, five were healthy prior to treatment and received oral diazepam for the treatment of inappropriate urination, intercat aggression, or skin disease. Two cats which received diazepam exhibited other clinical signs: one had chronic vomiting, and the other received diazepam after biochemical evidence of hepatocellular necrosis was present. Onset of clinical sings in cats receiving oral diazepam occurred 7–13 days following the initiation of treatment. Clinical signs and clinical biochemical analysis were compatible with severe hepatocellular necrosis and acute liver failure. All cats had lesions in other organs: five had pancreatic disease, five had cardiac disease, and five had renal disease. All cats died, or were euthanized, within 4 dyas of the onset of clinical signs and 2 days after presentation to a veterinarian. Fatal, acute, centrilobular hepatic necrosis appears to be a serious adverse reaction to diazepam therapy in certain cats.  相似文献   
95.
In a retrospective study of 21 dogs with intestinal adenocarcinoma, the signalment, clinical presentation, laboratory findings, ultrasonographic features, treatment, and outcome were reviewed. Anorexia (n = 16), vomiting (n = 15), diarrhea (n = 10), and weight loss (n = 9) were the most common clinical signs reported. Ultrasonographic features that were evaluated included location, length, wall thickness, echogenicity, regional motility, layering, regional lymphadenopathy, and fluid accumulation proximal to the lesion site. All lesions were transmural and associated with complete loss of wall layering. Maximum wall thickening at the lesion site ranged from 7 to 17 mm (median 12 mm, mean 11.9 mm). Most of the dogs had a lesion measuring from 23 to 63 mm in length, (median 40 mm, mean 42 mm). Most intestinal lesions were poorly echogenic and had an irregular lumen. Fluid accumulation proximal to the lesion site was identified in 17 of 21 dogs, and in 13 of 17 dogs the fluid accumulation was considered moderate to severe. Regional lymphadenopathy and/or nodular mesentery/omentum were noted in 12 of 21 dogs. The tumor was located in small intestine for 15 dogs and in the colon for the remaining 6 dogs. Fifteen dogs were treated by surgical resection of the intestinal mass. Their median survival time was 233 days. Only gender appeared to influence survival. Female dogs lived a median of 28 days, whereas male dogs lived a median of 272 days.  相似文献   
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An in utero tibial fracture was examined at necropsy in a seven-month-old male aborted Thoroughbred fetus. Grossly the healed fracture had a smooth cortical surface. Histologically there was no callus formation or excessive osteoclastic or osteoblastic activity.  相似文献   
100.
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