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81.
Two 10 mm thick osteochondral grafts were harvested from the lateral aspect of the lateral trochlear ridge of the left talus in each of 10 anesthetized horses. The grafts were frozen in a 7.5% DMSO solution and stored in liquid nitrogen. The horses were anesthetized again on day 14 and the thawed grafts were press-fitted into drill holes in the trochlear ridges of the right stifle. A fresh graft was transferred from the right hock to the left stifle. To control for the effects of surgery, another fresh graft was transferred from the right stifle to the left stifle. The result was two grafts in each femoropatellar joint. Fresh and frozen osteoarticular autografts appeared to maintain a durable weight-bearing surface for 3 months; however, the fresh grafts were clearly superior. Frozen grafts had fewer living chondrocytes, decreased safranin-O staining, and decreased SO435 uptake. Graft stability and articular surface congruency were determining factors in the outcome of all grafts. Since the availability of osteochondral autografts is limited, further work on the use of preserved allogeneic osteochondral tissue is warranted.  相似文献   
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This paper considers the behavior of actors in real estate markets in the face of environmental uncertainty. Environmental legislation has increased in scale and scope with obvious implications for property markets. Developers, investors, occupiers, and lenders may all be affected by changing environmental standards. Any factor that creates valuation uncertainty will have major impacts. Blighted sites and properties will be shunned, while existing real estate portfolios will be adversely affected. A survey of UK property practitioners on their attitudes to environmental hazard reveals that firms seem pessimistic as to their ability to quantify and model the economic and investment implications of environmental risk. There are concerns here for the wider economy and for the business community through supply-side constraints and suboptimal location. There are implications, too, for local and regional regeneration strategies as whole areas may be blighted by potential contamination. There may be mispricing and arbitrage opportunities in relation to such assets that can be exploited through first mover advantage by firms willing and able to develop effective risk-sensitive appraisal models.  相似文献   
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The clinical signs, laboratory findings and pathological changes are described in two cases of inherited copper toxicosis in the Bedlington terrier. The first case presented with acute signs of depression, vomiting, anorexia, weight loss and jaundice while the second case followed a more chronic course with less severe clinical signs which included weight loss and ascites. Both dogs had elevated circulating levels of alanine aminotransferase (ALT), however other haematological and biochemical parameters, while reflecting liver involvement, varied between the two cases. Chemical analysis of the liver revealed elevated copper levels in both cases (951·7 and 1093·4 μg/g wet weight respectively; normal less than 150 μg/g). These levels, however, are less than some affected but asymptomatic Bedlington terriers. Pathologically the first case had micronodular cirrhosis, while the second had focal hepatitis with fibrosis. Both dogs showed vacuolation of the white matter in the cerebrum, cerebellum, midbrain and medulla. Attention is drawn to the similarities and differences between copper toxicosis in the Bedlington terrier and Wilson's disease in man.  相似文献   
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Complications developed with the clinical use of Ellis pins in external skeletal fixation in seven dogs weighing 11 to 24 kg. Pins broke at the threaded-nonthreaded shaft junction in six dogs, and there was radiographic evidence of pin loosening six dogs. One pin pulled out causing loss of fixation in one dog. These complications with the recently introduced Ellis pin emphasize a need for further evaluation of its proper use.  相似文献   
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Objective To evaluate the administration of procaine penicillin prior to or during confinement with head elevation as a means of reducing the associated accumulation of inflammatory lower respiratory tract secretions and increased numbers of bacteria within the lower respiratory tract of confined horses. Design and Procedure Two experiments were conducted to evaluate the efficacy of different dose rates and dosing frequencies. In experiment A a single low dose (15,000 IU/kg) of procaine penicillin was administered to four horses immediately prior to confinement with head elevation for 48 hours. The systemic leucocyte response, gross and cytologic characteristics of transtracheal aspirate and bacterial numbers in lower respiratory tract samples were compared with corresponding samples from two horses confined with heads elevated but not given penicillin. The efficacy of higher dose rates (20,000 IU/kg and 40,000 IU/kg) given before and during confinement with heads elevated for 24 hours was evaluated in experiment B. Results Treatment with procaine penicillin had no effect on the systemic leucocyte response or on the accumulation of inflammatory lower respiratory tract secretions at any of the dosing schedules evaluated. The number of bacteria isolated from trans-tracheal samples was reduced at 12 hours for treated horses in experiment A and at 24 hours for experiment B. β-haemolytic Streptococcus spp were not isolated from treated horses in either experiment. Bacterial species isolated from treated horses were predominantly Pasteurella and/or Actinobacillus spp, however, members of the family Enterobacteriaceaé and a Staphylococcus sp were isolated from treated horses. One treated horse in experiment A developed clinically apparent pulmonary disease. Conclusions The prophylactic administration of penicillin before or during confinement did not reliably reduce bacterial numbers or prevent the accumulation of purulent lower respiratory tract secretions in horses confined with their heads elevated. Numbers of β-haemolytic Streptococcus spp were reduced following treatment, suggesting that the repeated administration of procaine penicillin may have some merit as part of a strategy to prevent transport-associated respiratory disease. However, methods directed at minimising the duration of confinement with head elevation, augmentation of the clearance of accumulated secretions and prompt identification of animals in which airway inflammation has extended to the pulmonary parenchyma remain the best ways of minimising transport-associated respiratory disease.  相似文献   
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Serum from 30 young alligators was examined by free boundary, starch block, and cellulose acetate strip electrophoresis. The patterns obtained showed that the alligator serum proteins differ significantly from those of other chordates in that an alpha-globulin is the major component. The average ratio of alpha-globulin to albumin in the serum is 3.4. In this respect it resembles serum of human beings with renal disease in which the alpha-globulin ratio to albumin ratio reaches 3.0.  相似文献   
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