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101.
Liza Wittenberg-Voges Sabine BR. Kästner Marja Raekallio Outi M. Vainio Karl Rohn Klaus Hopster 《Veterinary anaesthesia and analgesia》2018,45(2):165-174
Objective
To compare the effects of MK-467 during isoflurane anaesthesia combined with xylazine or dexmedetomidine on global and gastrointestinal perfusion parameters.Study design
Prospective, randomized experimental trial.Animals
A total of 15 warmblood horses.Methods
Horses were divided into two groups for administration of either dexmedetomidine (D) or xylazine (X) for premedication (D: 3.5 μg kg?1; X: 0.5 mg kg?1) and as constant rate infusion during isoflurane anaesthesia (D: 7 μg kg?1 hour?1; X: 1 mg kg?1 hour?1). During anaesthesia, heart rate, mean arterial blood pressure (MAP), systemic vascular resistance index (SVRI) and cardiac index (CI) were measured. Microperfusion of the colon, jejunum and stomach was measured using laser Doppler flowmetry. After 2 hours of stabilization, MK-467 (250 μg kg?1) was administered, and measurements were continued for another 90 minutes. For statistical analysis, the permutation test and Wilcoxon rank-sum test were used (p < 0.05).Results
There were no differences in baseline measurements between groups. The MK-467 bolus resulted in a significant decrease in MAP (D: –58%; X: –48%) and SVRI (D: –68%; X: –65%) lasting longer in group D (90 minutes) compared to group X (60 minutes). While CI increased (D: +31%; X: +35%), microperfusion was reduced in the colon (D: –44%; X: –34%), jejunum (D: –26%; X: –33%) and stomach (D: –37%; X: –35%).Conclusions and clinical relevance
Alpha-2-agonist induced vasoconstriction was reversed by the MK-467 dose used, resulting in hypotension and rise in CI. Gastrointestinal microperfusion decreased, probably as a result of insufficient perfusion pressure. An infusion rate for MK-467 as well as an ideal agonist/antagonist ratio should be determined. 相似文献102.
Objective
To evaluate the transdermal local anaesthetic effect of lidocaine or lidocaine combined with prilocaine or tetracaine in horses.Study design
Experimental, randomized study.Animals
A total of five healthy adult warmblood horses.Methods
Horses were clipped bilaterally at the withers, cranial saddle area and caudal saddle area. Baseline measurements for mechanical superficial sensation via von Frey filaments and nociceptive thermal thresholds were performed. A 5% lidocaine patch (12 hour exposure, treatment L), a lidocaine/prilocaine cream (each 2.5%, treatment LP) and a lidocaine/tetracaine cream (each 7%, treatment LT) were applied (both 2 hour exposure). The same product was applied at the same location bilaterally, but on the right side an epidermal micro-perforation (dermaroller, 1200 needles) was performed prior to application. A total of five more measurements were performed at each location, immediately at the end of exposure time followed by hourly measurements. Thermal thresholds normalized to thermal excursion were analysed. One- or two-way anova and the Wilcoxon signed-rank test were used for statistical analysis with p < 0.05 considered significant.Results
Epidermal micro-perforation had no enhancing effect. Treatments L, LP, and LT resulted in increased thermal excursion (%) immediately (84.7 ± 12.9; 100.0 ± 0.0; 100.0 ± 0.0) and 1 hour (81.7 ± 66; 86.0 ± 17.7; 87.7 ± 14.4) after the removal of the respective product compared to baseline (66.1 ± 9.3; 69.9 ± 8.3; 76.5 ± 7.8). Superficial mechanical sensation was decreased by the lidocaine-and-tetracaine cream at all time points, and by the lidocaine patch and lidocaine-and-prilocaine cream for three measurements.Conclusions and clinical relevance
Eutectic mixtures of lidocaine with either prilocaine or tetracaine led to a reduction in thermal nociception and mechanical sensation for up to 2 hours. 相似文献103.
The relationship between acidity and benthic invertebrate communities was investigated in two small streams in coniferous forests in central Jutland, Denmark, during 1992 and 1993. Stream pH was acid (mean pH 4.8 and 5.4) and alkalinity fluctuated greatly with mean values around zero. During rain events, water from springfed reaches upstream were mixed downstream with brown humic acid water with high aluminium content, and pH declined from circumneutral near the springs down to pH below 4 over a very short distance (0.5–1.5 km). The benthic invertebrate communities in the most acidic downstream reaches of both streams were dominated by filipalpian stoneflies, mainly Leuctra nigra (Olv.). Community composition remained very similar throughout the sampling period despite variations in pH. In the upper (neutral) reaches invertebrates intolerant of low pH such as Gammarus pulex L. were found. The concentrations of chloride and sulphate in the streams were more than double the concentrations in a nearby moorland stream indicating a strong impact of acidifying atmospheric deposition on the two forest streams. Results of this study indicate that afforestation with conifers on sandy Danish soils with low buffering capacity (about 25% of the total Danish land area) may lead to an increased acidification of surface waters and thereby also to an impoverished aquatic fauna. 相似文献
104.
The frequencies of B-alleles in RDM were analysed in samples of 637 bulls born in 1963–64–65, 794 bulls born in 1960–61–62 and 1226 cows from common herds.Among the 46 distinct alleles for which frequencies were estimated only about 10 alleles have frequencies above 1 %. The frequency of some alleles shows consistent variations during the last 10–15 years.The degree of homozygosity at the B-locus has remained almost constant among bulls during the last 10–15 years, while the homozygosity among cows from common herds shows a decreasing tendency. 相似文献
105.
106.
L J Larsen J K Roush R M McLaughlin 《Journal of the American Animal Hospital Association》1999,35(3):243-250
Bone plate fixation was reviewed in 29 distal radial fractures of small- and miniature-breed dogs. Twenty-two fractures in 18 dogs were available for follow-up. Number of complications and return to function were evaluated. Complications occurred in 54% of the fractures. Catastrophic complications occurred in 18% of fracture repairs with follow-up, while minor complications occurred in 36%. Sixteen (89%) of 18 dogs had a successful return to function. Bone plate fixation is a successful repair method for distal radius and ulna fractures in small-breed dogs, compared to previously reported methods. 相似文献
107.
K. H. Sutton N. G. Larsen M. P. Morgenstern M. Ross L. D. Simmons A. J. Wilson 《Cereal Chemistry》2003,80(6):707-711
Dough development using sheeting and mechanical dough development (MDD) were compared with respect to the effect the mixing method had on the molecular size distribution and degree of protein thiol exposure of the aggregated glutenin proteins. Although sheeting imparts a lower rate of work input on doughs than does MDD mixing, changes in protein aggregation patterns during mixing were similar for both methods of dough development, indicating that protein disaggregation was important in the process of dough development. In both systems, a reduced rate of change in the protein aggregation patterns was associated with optimum dough development. The MDD mixing was characterized by increasing exposure of the thiol groups on the SDS‐insoluble glutenin during mixing while the sheeting process resulted in fewer exposed thiol groups on both SDS‐soluble and SDS‐insoluble glutenin proteins. This suggested that disulfide bond rupture may not be a required process in dough development and that high effective stresses per se may not be required to develop doughs. This is consistent with a model for dough development that does not require extensive covalent bond rupture but instead involves mainly rupture and reformation of noncovalent interactions such as hydrophobic bonds and hydrogen bonds between protein chains. 相似文献
108.
Kim Birnie-Gauvin Martin H. Larsen Kim Aarestrup William G. Willmore Steven J. Cooke 《Fish physiology and biochemistry》2018,44(1):137-142
Levels of oxidative stress can be affected by a range of compounds including toxins and pharmaceuticals. Antioxidants are important protective compounds which counteract the damaging effects of oxidative stress. Glutathione (GSH) is one of the main antioxidants for many organisms and can be synthesized from administered N-acetylcysteine (NAC). NAC has therefore often been used in a wide range of taxa to manipulate levels of GSH. Our objective was to validate this approach in a wild temperate teleost fish model, the brown trout (Salmo trutta). We used intracoelomic injections of NAC in saline and vegetable shortening, at two different concentrations (100 and 400 mg/kg), with the appropriate controls and shams, under controlled laboratory settings. We found that NAC failed to elicit an increase in GSH over three time periods and concluded that NAC is not an effective method to enhance GSH levels in teleost fish using the concentrations and vehicles tested here. We emphasize the importance of validation studies across all new species/taxa when possible and suggest that more investigation is required with regard to NAC manipulation in fish if this approach is to be used. 相似文献
109.
110.
Aamot H. U. Ward T. J. Brodal G. Vrålstad T. Larsen G. B. Klemsdal S. S. Elameen A. Uhlig S. Hofgaard I. S. 《European journal of plant pathology / European Foundation for Plant Pathology》2015,142(3):501-519
European Journal of Plant Pathology - As has been observed in several European countries, the frequency of Fusarium head blight (FHB) caused by members of the Fusarium graminearum species complex... 相似文献