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REASONS FOR PERFORMING STUDY: Anecdotal reports suggest that laser-facilitated arthrodesis of the distal tarsal joints improves the prognosis compared with intra-articular drilling but no objective comparisons have been performed. OBJECTIVES: To evaluate intra-articular drilling and laser-facilitated arthrodesis using in situ and in vivo techniques. METHODS: Fourteen cadaver limbs were evaluated in situ for chondrocyte viability after both surgical techniques. In vivo, one randomly selected limb was subjected to laser-facilitated arthrodesis and the other underwent intra-articular drilling in 6 normal horses. Clinical examinations were performed at 1, 3 and 5 months. Two horses were subjected to euthanasia at 1, 3 and 5 months. RESULTS: Significantly more chondrocyte death was observed with laser-facilitated arthrodesis compared to drilling, but the overall degree suggested only a focal effect. In vivo, both groups demonstrated minimal post operative morbidity. There was more evidence of arthrodesis seen at all time points with intra-articular drilling. CONCLUSIONS: This study demonstrated that changes associated with ultimate arthrodesis occur earlier after intra-articular drilling of the distal tarsal joints than laser-facilitated arthrodesis, although clinically affected horses may respond differently. POTENTIAL RELEVANCE: Intra-articular drilling may provide earlier arthrodesis of the distal tarsal joints, but not necessarily a better long-term result.  相似文献   
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The in vitro reactivity of vasoconstrictive mediators that are implicated in acute laminitis was determined in palmar and plantar digital arteries and veins obtained from healthy horses and in palmar digital vessels of horses with early laminitis (Obel grade I). To obtain baseline reactivity data, 3 experiments were conducted, using healthy horses: (1) the reactivity of palmar and plantar digital arteries and veins to angiotensin II, norepinephrine, and 5-hydroxytryptamine (serotonin) were compared; (2) the direct effects of bacterial endotoxin on vascular reactivity were assessed; and (3) the reactivity of palmar digital arteries and veins to angiotensin II, norepinephrine, prostaglandin F2 alpha (PGF2 alpha), serotonin, and a thromboxane-endoperoxide analog (U46619) were determined. The vascular reactivity of these same 5 vasoconstrictors then was determined in horses with early laminitis and was compared with data from healthy (control) horses. Obel grade-I laminitis was experimentally induced in horses, using carbohydrate overload. Dose responses were conducted for each agent at concentrations between 10(-8)M and 10(-4)M. The potency of a drug was defined as the mean effective concentration necessary to induce 50% of maximal contraction (EC50). There were no differences in EC50 concentrations and in maximal contractions between forelimb and hind limb arteries and veins for angiotensin II, norepinephrine, and serotonin. Incubation with endotoxin had no effect on the reactivity of arteries and veins to angiotensin II, norepinephrine, and serotonin.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Oral prophylactic medication with either procaine penicillin G or a mixture of chlortetracycline, sulphadimidine and procaine penicillin G reduced the incidence of streptococcal meningitis in a herd of pigs with a high recorded prevalence of the disease, but to a significant extent (P less than 0.01) only in those pigs receiving procaine penicillin G. Subsequent studies showed that after oral administration of procaine penicillin G, benzylpenicillin was detectable in plasma only at very low concentration and similar results were obtained using the potassium salt of penicillin G. However, phenoxymethyl penicillin administered orally provided high plasma concentrations of this drug. A further investigation demonstrated that despite the low plasma concentrations of penicillin after oral administration of the procaine salt, gastrointestinal and urinary concentrations of the drug were relatively high for up to five hours.  相似文献   
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Five trials were conducted to evaluate the effects of the presence of horns on cattle on carcase bruising. In each trial there were three groups of cattle, hornless, horned and mixed (some with hrons and some without). The weight of bruised tissue trimmed from the carcases of the cattle in the horned groups was significantly greater than that trimmed from the carcases of the cattle in the hornless groups. When horned and hornless cattle are mixed the hornless animals in the mixed group sustain significantly more bruising than animals in a group consisting soley of hornless animals while the horned animals in a mixed group have a similar degree of bruising to cattle in a group consisting solely of horned cattle.  相似文献   
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Cysts in the dental cavities of dogs are rare. This report documents the case of a young boxer that was referred after having had treatment for bilateral oral swellings. Dentigerous cysts were tentatively diagnosed. Surgery was performed to aspirate the fluid and remove the first premolars, which were positioned in the cysts. Histopathological examination of tissue collected during the surgical procedure confirmed the diagnosis.  相似文献   
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The influence of albumin on the pasting and rheological properties of rice flour was investigated. Albumin was removed from the flour of three rice cultivars (Amaroo, Opus, and Langi) by water extraction and the pasting profile of the albumin‐depleted flour was analyzed using the Rapid ViscoAnalyser (RVA). Removal of albumin resulted in a significant (P < 0.5) decline in all the pasting parameters measured. When the extracted albumin was added to pure rice starch, exactly opposite trends occurred. The concentration of albumin in rice starch had a positive linear relationship with all pasting parameters measured. When the gels formed after RVA analyses were analyzed using the TA‐TX2 texture analyzer, the concentration of albumin had a positive linear relationship with hardness, but a near linear negative relationship with adhesiveness. The presence of albumin in rice starch slowed the uptake of water by starch in the initial stages of cooking, but the water uptake accelerated in later stages, and the final water absorption was higher in the samples containing albumin than in pure starch. The water‐soluble nature of albumin suggests that protein‐water‐starch interactions could be responsible for its effect on the physical properties of rice.  相似文献   
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