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31.
OBJECTIVE: To develop a model for measuring rotary stability of the canine elbow joint and to evaluate the relative contribution of the anconeal process (AN), lateral collateral ligament (LCL), and medial collateral ligament (MCL). SAMPLE POPULATION: 18 forelimbs from 12 canine cadavers. PROCEDURE: Forelimbs were allocated to 3 experimental groups (6 forelimbs/group). Each intact forelimb was placed in extension at an angle of 135 degrees and cycled 50 times from -16 degrees (pronation) to +28 degrees (supination) in a continuous manner at 2.0 Hz. Cycling was repeated following sectioning of the structure of interest (group 1, AN; group 2, LCL; and group 3, MCL). Torque at -12 degrees (pronation) and +18 degrees (supination) was measured for each intact and experimentally sectioned limb. A Student t test was performed to compare torque values obtained from intact verses experimentally sectioned limbs and for comparison with established criteria for differentiation of primary (> or = 33%), secondary (10 to 33%), and tertiary rotational stabilizers (< 10%). RESULTS: In pronation, the AN was the only primary stabilizer (65%). For supination, the LCL was a primary stabilizer (48%), AN was a secondary stabilizer (24%), and MCL was a tertiary stabilizer (7%). CONCLUSIONS AND CLINICAL RELEVANCE: With the elbow joint in extension at an angle of 135 degrees, the AN is a primary rotational stabilizer in pronation, and the LCL is a primary stabilizer in supination. Disruption of the AN or LCL may affect rotary range of motion or compromise stability of the elbow joint in dogs.  相似文献   
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Anticancer vaccines.   总被引:1,自引:0,他引:1  
With the tools of molecular biology and a greater understanding of mechanisms to harness the immune system, effective tumor immunotherapy is becoming a reality. This new class of therapeutics offers a more targeted, and therefore precise, approach to the treatment of cancer. The recent conditional licensure of a xenogeneic DNA vaccine for advanced canine malignant melanoma strongly suggests that immunotherapy can play an extremely important role alongside the classic cancer treatment triad components of surgery, radiation therapy, and chemotherapy.  相似文献   
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Serum testosterone concentrations and the spermiograms of prepuberal bulls fed two levels of protein diets were investigated at 7, 10, 14 and 18 months of age. Scrotal circumference, body condition score and total sperm counts of those animals on a high protein diet were significantly (P <0.05) higher than those on a low protein diet. However, sperm motility, total dead sperm and abnormal sperm did not differ between the treatment groups (P <0.05). One bull fed a high protein diet had significantly higher testosterone concentrations (basal and peak) than a bull fed low protein throughout the four sampling periods (P <0.05). Testosterone concentrations, scrotal circumference, volume of semen, sperm concentration and sperm output of bulls on low and high protein diets increased significantly with age (P <0.05). Peak testosterone concentrations ranged from 1.1. ng ml−1 at 7 months to a maximum of 5.3 ng ml−1 at 18 months. The 24 h secretory patterns of testosterone were episodic, pulsatile or temporal in nature. The peaks occurred mostly in the morning hours and ranged from one to five in number. Protein intake in prepubertal bulls could have significant influence on spermiogram and testosterone production.  相似文献   
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The objective of the current study was to describe and characterize the pharmacokinetics and selected pharmacodynamic effects of morphine and its two major metabolites in horses following several doses of morphine. A total of ten horses were administered a single intravenous dose of morphine: 0.05, 0.1, 0.2, or 0.5 mg/kg, or saline control. Blood samples were collected up to 72 hr, analyzed for morphine, and metabolites by LC/MS/MS, and pharmacokinetic parameters were determined. Step count, heart rate and rhythm, gastrointestinal borborygmi, fecal output, packed cell volume, and total protein were also assessed. Morphine‐3 glucuronide (M3G) was the predominant metabolite detected, with concentrations exceeding those of morphine‐6 glucuronide (M6G) at all time points. Maximal concentrations of M3G and M6G ranged from 55.1 to 504 and 6.2 to 28.4 ng/ml, respectively, across dose groups. The initial assessment of morphine pharmacokinetics was done using noncompartmental analysis (NCA). The volume of distribution at steady‐state and systemic clearance ranged from 9.40 to 16.9 L/kg and 23.3 to 32.4 ml min?1 kg?1, respectively. Adverse effects included signs of decreased gastrointestinal motility and increased central nervous excitation. There was a correlation between increasing doses of morphine, increases in M3G concentrations, and adverse effects. Findings from this study support direct administration of purified M3G and M6G to horses to better characterize the pharmacokinetics of morphine and its metabolites and to assess pharmacodynamic activity of these metabolites.  相似文献   
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This retrospective study reports on the clinical presentation of equine atopic skin disease and evaluates response to treatment with allergen-specific immunotherapy (ASIT) based on intradermal testing and/or serum testing. Computerized medical records from January 1991 to December 2008 yielded 54 horses included in the study. Presenting clinical signs (CS) included urticaria (n=28), pruritus (n=8) or both (n=18). Forty-one of 54 horses received ASIT, and response to ASIT (n=32) was evaluated via telephone survey. Eighty-four per cent (n=27) of owners reported that ASIT reduced their horse's CS; 59% (n=19) were able to manage CS by ASIT alone. Three horses (9%) were managed with ASIT in combination with doxepin and discontinued use of corticosteroids. There was no statistical significance between type of test performed and reported success of ASIT (χ(2) analysis, P=0.53). Ninety-three per cent (n=30) of owners reported use of antipruritic medications prior to starting ASIT; 57% (n=17) of these owners reported discontinuing those medications due to success of ASIT. Adverse effects were limited to swelling at the injection site, seen in 16% (n=5). Seventy-five per cent (n=24) of owners elected to discontinue ASIT after 6 months to 8 years (mean 2.2 years): 15 due to resolution of CS, six due to persistent CS, two because the horse was sold, and one due to cost. Ten owners reported no recurrence of CS after discontinuing ASIT; five had recurrence within a median of 2 years of discontinuing ASIT (range 1-12 years). Allergen-specific immunotherapy is a safe and effective way to manage equine atopic skin disease.  相似文献   
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BACKGROUND: A syndrome of relative adrenal insufficiency has been identified in septic humans, and is associated with hypotension and death. Relative adrenal insufficiency is generally associated with basal serum cortisol concentration within or above the reference range and a blunted cortisol response to adrenocorticotropic hormone administration. It is unknown whether relative adrenal insufficiency occurs in septic dogs. HYPOTHESIS: That relative adrenal insufficiency occurs in septic dogs, and that relative adrenal insufficiency is associated with hypotension and mortality. ANIMALS: Thirty-three septic dogs admitted to a small animal intensive care unit. METHODS: Dogs were included in the study if they had a known or suspected infectious disease and had systemic inflammatory response syndrome. Dogs were excluded if they had disease or medication history expected to affect the hypothalamic-pituitary-adrenal axis. Serum cortisol and endogenous plasma adrenocorticotropic hormone concentrations were measured before, and serum cortisol concentration measured 1 hour after, intramuscular administration of 250 microg of cosyntropin/dog. The change in cortisol concentration (delta-cortisol) before and after cosyntropin administration was determined in each dog. RESULTS: Hypotension was associated with lower delta-cortisol values (OR 1.3; CI 1.0-1.9; P = .029). delta-Cortisol cutoff of 3.0 microg/dL was most accurate for predicting hypotension, survival to discharge, and 28-day survival. The rate of death in dogs with delta-cortisol < or = 3 microg/dL was 4.1 times that of dogs with delta-cortisol > 3 microg/dL (RR 4.1; CI 1.5-12.3; P = .01). CONCLUSIONS AND CLINICAL RELEVANCE: Delta-cortisol < or = 3 microg/dL after adrenocorticotropic hormone administration is associated with systemic hypotension and decreased survival in septic dogs.  相似文献   
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