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991.
Effect of adipose-derived nucleated cell fractions on tendon repair in horses with collagenase-induced tendinitis 总被引:1,自引:0,他引:1
Nixon AJ Dahlgren LA Haupt JL Yeager AE Ward DL 《American journal of veterinary research》2008,69(7):928-937
OBJECTIVE: To assess the potential of adipose-derived nucleated cell (ADNC) fractions to improve tendon repair in horses with collagenase-induced tendinitis. ANIMALS: 8 horses. PROCEDURES: Collagenase was used to induce tendinitis in the superficial digital flexor tendon of 1 forelimb in each horse. Four horses were treated by injection of autogenous ADNC fractions, and 4 control horses were injected with PBS solution. Healing was compared by weekly ultrasonographic evaluation. Horses were euthanatized at 6 weeks. Gross and histologic evaluation of tendon structure, fiber alignment, and collagen typing were used to define tendon architecture. Biochemical and molecular analyses of collagen, DNA, and proteoglycan and gene expression of collagen type I and type III, decorin, cartilage oligomeric matrix protein (COMP), and insulin-like growth factor-I were performed. RESULTS: Ultrasonography revealed no difference in rate or quality of repair between groups. Histologic evaluation revealed a significant improvement in tendon fiber architecture; reductions in vascularity, inflammatory cell infiltrate, and collagen type III formation; and improvements in tendon fiber density and alignment in ADNC-treated tendons. Repair sites did not differ in DNA, proteoglycan, or total collagen content. Gene expression of collagen type I and type III in treated and control tendons were similar. Gene expression of COMP was significantly increased in ADNC-injected tendons. CONCLUSIONS AND CLINICAL RELEVANCE: ADNC injection improved tendon organization in treated tendons. Although biochemical and molecular differences were less profound, tendons appeared architecturally improved after ADNC injection, which was corroborated by improved tendon COMP expression. Use of ADNC in horses with tendinitis appears warranted. 相似文献
992.
Joyner PH Jones MP Ward D Gompf RE Zagaya N Sleeman JM 《American journal of veterinary research》2008,69(1):13-22
OBJECTIVE: To compare induction and recovery characteristics and cardiopulmonary effects of isoflurane and sevoflurane in bald eagles. Animals-17 healthy adult bald eagles. PROCEDURES: Anesthesia was induced with isoflurane or sevoflurane delivered in oxygen via a facemask in a crossover design with 4 weeks between treatments. Eagles were intubated, allowed to breathe spontaneously, and instrumented for cardiopulmonary measurements. Time to induction, extubation, and recovery, as well as smoothness of recovery, were recorded. RESULTS: Administration of sevoflurane resulted in a significantly quicker recovery, compared with isoflurane. Temperature, heart rate, and respiratory rate significantly decreased over time, whereas systolic (SAP), diastolic (DAP), and mean arterial blood pressure (MAP) significantly increased over time with each treatment. Temperature, heart rate, SAP, DAP, and MAP were significantly higher with isoflurane. Blood pH significantly decreased, whereas PaCO(2) significantly increased over time with each treatment. Bicarbonate and total carbon dioxide concentrations significantly increased over time with each treatment; however, there was a significant time-treatment interaction. The PaO(2) and arterial oxygen saturation increased over time with isoflurane and decreased over time with sevoflurane with a significant time-treatment interaction. Six eagles developed cardiac arrhythmias with isoflurane, as did 4 with sevoflurane anesthesia. CONCLUSIONS AND CLINICAL RELEVANCE: Isoflurane and sevoflurane administration resulted in smooth, rapid induction of and recovery from anesthesia similar to other species. Isoflurane administration resulted in tachycardia, hypertension, and more arrhythmias, compared with sevoflurane. Sevoflurane was associated with fewer adverse effects and may be particularly beneficial in compromised bald eagles. 相似文献
993.
Ulcerative enteritis is a disease that typically responds well to medication. An outbreak of ulcerative enteritis that was persistent and unresponsive to treatment is described. The outbreak started in semimature birds and progressively spread to younger birds. Confounding factors leading to this persistence were a significant coccidosis problem, a feed mixing error, and suspected antibiotic resistance. Although Clostridium colinum was never isolated, a bacitracin-resistant Clostridium perfringens was cultured from affected birds. Only the combined treatment of the flocks with an anticoccidial and tylosin was effective in controlling clinical disease. Numerous other management and treatment strategies were unsuccessful in lowering the severe mortality. 相似文献
994.
995.
Christensen J McNab B Stryhn H Dohoo I Hurnik D Kellar J 《Preventive veterinary medicine》2008,83(2):170-185
We report the methods and findings of a survey of Canadian swine producers summarizing farm-types at-risk of foreign animal disease (FAD) and the routine movement of animals, semen and workers among swine farms, as observed during a 42-day period. Of the 311 producers who returned completed questionnaires, 17% represented swine-herds with no swine or semen movement on or off the farm during the 42 days, 57% were sow herds or farrow-to-finish herds with limited movement onto the farm but movement off the farm, and 26% were swine-herds with movements on and off the farm. A substantial number of premises (>50% in some provinces) with swine also kept other animal species on the same premises. We applied the empirical movement data from the survey in a stochastic simulation model to estimate the number of herds infected and the basic regional distribution of infection that could be expected to occur if the FAD was not detected and routine movements were permitted to occur up to 42 days after infection with a FAD of a single randomly selected herd. Forty-five percent of the simulations did not involve spread beyond the index farm, whereas 34.8% involved spread among five or more farms after 42 days of routine movement. 相似文献
996.
Clifford R. Berry DVM John H. Kuperus PhD Daniel Malone BA 《Veterinary radiology & ultrasound》1995,36(1):57-63
Five mixed-breed dogs underwent splenic sequestration scintigraphy following intravenous injection of 647.5 to 740 MBq (17.5–20 mCi) of 99mTechnetium labeled autologous red blood cells (RBCs) that had been chemically denatured using two μg of stannous chloride. Left lateral dynamic images were obtained for 20 minutes after injection. Regions of interest (ROI) were drawn around the splenic body and ventral extremity, ventral liver and caudal abdominal great vessels and time activity curves created. Count density information was obtained and uptake ratios were calculated for the spleen ROI/vessel ROI, liver ROI/vessel ROI and spleen ROI/liver ROI at 1, 2.5, 5, 10, 15 and 20 minutes after injection. Two additional studies using different RBC denaturing procedures were done in four of the five dogs. In the second study, the stannous chloride level was doubled to 4.0 μg, while in the third study, the RBCs were denatured by addition of 2.0 μg of stannous chloride and heating at 49°C for 15 minutes. Progressive splenic uptake of denatured RBCs was seen in all dogs during the first 15 to 20 minutes of each study, no matter which denaturing technique was utilized. Significant increases in the spleen ROI:/vessel ROI and spleen ROI:liver ROI ratios were obtained at 5, 10, 15 and 20 minutes when compared to the 1 minute values for each of the labeling techniques. A significant difference was not identified between the three ratios at 15 minutes between the three labeling techniques. There was a trend of increasing values for each ratio where 2.0 μg of stannous chloride technique being the lowest, 4.0 μg of stannous chloride having an intermediate value and the heated technique had the highest values. The heating technique resulted in higher liver activity and increased variability of the mean liver ROI/vessel ROI ratios at all times (1, 2.5, 5,10, and 15 minutes). Using a non-linear least squares regression analysis, a double exponential equation fit the spleen ROI/vessel ROI and spleen ROI/liver ROI ratios for all three labeling techniques. Imaging of the spleen using all three techniques was acceptable, and a persistent blood pool image would allow for vascular imaging and cardiac gated studies 30 minutes after injection of the denatured, labeled autologous red blood cells. Veterinary Radiology & Ultrasound, Vol. 36, No. I, 1995, pp 57–63. 相似文献
997.
The bactericidal activity of N-acetyl-beta-D-glucosaminidase (NAGase) on some of the potential bacterial pathogens of the cow was determined. NAGase treatment significantly decreased the mean log10 number of Actinomyces pyogenes (P less than 0.01) and Staphylococcus aureus (P less than 0.05) after 2 and 4 hours of incubation at 37 degrees C. Similarly NAGase treatment significantly (P less than 0.05) reduced the mean log10 number of Streptococcus agalactiae and Pseudomonas aeruginosa after 4 hours incubation at 37 degrees C. NAGase did not reduce the numbers of Escherichia coli or Enterobacter aerogenes after either 2 or 4 hours incubation. Since NAGase and presumably other lysosomal enzymes are free on normal mucosal surfaces such as the uterus it is suggested that this direct bactericidal activity may be an important component of the normal defense mechanisms. 相似文献
998.
Some aspects of the bovine uterine defense mechanisms were evaluated over two successive estrous cycles in five adult nonpregnant Friesian cows. Uterine flushings and blood samples were taken from each cow during the estrus and diestrus phases of each estrous cycle. A significant higher percentage of Candida albicans (C. albicans) were phagocytosed (P < 0.01) and killed (P < 0.05) by blood neutrophils during estrus than during diestrus. N-acetyl-β-D-glucosaminidase activity of uterine flushings, blood neutrophil alkaline phosphatase activity scores, and serum progesterone concentrations during diestrus increased significantly (P < 0.01) compared to those at estrus. Mean total blood leucocyte and monocyte counts increased significantly (P < 0.05) during estrus compared to diestrus .
It is concluded, that the different hormonal status has at each stage of the estrous cycle a definite effect on uterine resistance against bacterial infection and a fall in serum progesterone concentrations is associated with an increased ability of blood neutrophils to phagocytose and kill C. albicans . 相似文献
It is concluded, that the different hormonal status has at each stage of the estrous cycle a definite effect on uterine resistance against bacterial infection and a fall in serum progesterone concentrations is associated with an increased ability of blood neutrophils to phagocytose and kill C. albicans . 相似文献
999.
1000.
Domingo Martínez-Romero Fabián Guillén Salvador Castillo Pedro Javier Zapata María Serrano Daniel Valero 《Postharvest Biology and Technology》2009,51(2):200-205
A scrubber to remove ethylene continuously from stored environments was developed. The device comprised a cartridge heater tightly joined to the activated carbon–1% Pd. The application of heat pulses led to an increase in ethylene oxidation and to auto-regeneration of the activated carbon. The efficacy of ethylene removal was higher with the number of heat pulses. Several combinations of exogenous ethylene concentrations and heater core temperatures (100–325 °C) of the device were assayed to determine their effectiveness in removing ethylene from the storage area. The results indicated that increasing the heater temperature led to enhanced percentages of eliminated ethylene but also increased CO2 concentrations. This CO2 could come from the activated carbon due to its breakthrough. Thus, temperatures ranging between 150 and 200 °C eliminated 96–99% of ethylene, with low CO2 accumulation (0.10–0.18 kPa) and without affecting the temperature of the storage environment. Thus, this device might be a promising tool for scrubbing ethylene from storage areas for fresh horticultural produce in which ethylene can induce detrimental effects. 相似文献