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81.
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82.
83.
Alexandra Keller Bettina Wingelhofer Barbara Peter Karin Bauer Daniela Berger Susanne Gamperl Martin Reifinger Sabine Cerny‐Reiterer Richard Moriggl Michael Willmann Peter Valent Emir Hadzijusufovic 《Veterinary and comparative oncology》2018,16(1):i-i
The cover image, by Alexandra Keller et al., is based on the Original Article The JAK2/STAT5 signaling pathway as a potential therapeutic target in canine mastocytoma, DOI: 10.1111/vco.12311
84.
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85.
86.
Modifications to atrazine degradation pathways in a loamy soil after addition of organic amendments 总被引:4,自引:0,他引:4
The effects of two organic amendments, a municipal solid waste compost and a composted straw, on [U-ring-
]atrazine degradation pathways in a loamy soil (Grignon, Yvelines, France) were studied during laboratory incubations under controlled conditions. Three month conditionings were conducted under sterile or non-sterile conditions, with soil plus atrazine, organic amendment plus atrazine, or soil plus organic amendment. Then either an organic amendment or soil or atrazine was added, respectively, to these three treatments and incubated for an additional 3 months under non-sterile conditions. Both organic amendments modified the behaviour of atrazine in soil but via different processes. The addition of municipal compost increased atrazine sorption and decreased its availability for degradation by soil microorganisms. The effect of the composted straw was mainly related to its high enzymatic activity, which appeared to be responsible for the production of large amounts of hydroxyatrazine. This hydroxylation favoured the opening of the triazine ring and its subsequent mineralization in the soil. At the end of the incubations, less atrazine was mineralized in the presence of the two types of organic amendment, which both increased the formation of non-extractable residues of atrazine. The addition of municipal compost preserved larger amounts of extractable atrazine, while the addition of composted straw enhanced hydroxyatrazine production. In all cases, the greatest effects were found when atrazine was directly in contact with the organic amendment during conditioning. 相似文献
87.
In permanent observation plots across Switzerland, nitrogen (N) concentration in the foliage of mature beech has increased by 15% and phosphorus (P) concentrations in beech and mature Norway spruce decreased by 12 and 13% respectively between 1984 and 1995, leading to increased N:P ratios. Modelled N deposition was correlated with stem increment in both beech and spruce, with indications of P limitation in some beech plots. Experimental application of 0-160 kg N ha-1> yr-1> over four to five years caused nutrient imbalances in various afforestation plots comparable to those observed in the permanent observation plots. The changes in the trees caused by N treatment led to increased attacks by parasites such as Apiognomonia errabunda, Phomopsis sp., Phyllaphis fagi in beech and Botrytis cinerea, Sacchiphantes abietis and Cinara pilicornis in Norway spruce. The results suggest current N deposition in Switzerland induces significant changes in the forest ecosystem. 相似文献
88.
Ontology-based simulation in agricultural systems modeling 总被引:1,自引:0,他引:1
A methodology and applications of ontology-based simulation are presented. An environment for building simulations based on the Lyra ontology management system is described which includes web-based visual design tools for constructing models and automatically generating simulation code. The ontology is used for representing all equations and all symbols appearing in these equations that are needed to describe a model. The example applications presented are models of soil, water, and nutrient management in citrus and sugarcane. Results thus far show that the ontology-based approach has advantages for representing the model structure, equations, and symbols, that complex models can be described in this format, and that efficient simulation code can be generated automatically from the ontology definition of the model. Potential applications, not yet fully explored, include ability to automatically connect models and data sources, using the ontology to organize model bases containing many models and model components, and using ontology reasoners to search for models, automatically discover model similarities and differences, and generate model instances from general principles. 相似文献
89.
The transformations of eight herbicides (atrazine, simazine, terbutryn, pendimethalin, carbetamide, 2,4-D, metsulfuron-methyl and dimefuron) in soil after compost addition were monitored during long-term laboratory incubations. The herbicides were applied to soil, compost and soil-compost mixtures. Herbicide sorption, their kinetics of mineralisation and the extractability of residues were compared in the different treatments. Compost addition to soil generally decreased herbicide mineralisation and favoured the stabilisation of herbicide residues. A fraction of the stabilised residues remained extractable and potentially available. However, most of them were unextractable and formed bound residues. Sorption could be at the origin of a kinetically limited biodegradation, mainly for the most highly-sorbed herbicides (atrazine, simazine, terbutryn, pendimethalin and dimefuron). Compost addition had little effects on the less sorbed herbicides (carbetamide, 2,4-D and metsulfuron- methyl). © 1997 SCI. 相似文献
90.
Fangio Vercruysse Sabine Drieghe Walter Steurbaut Willy Dejonckheere 《Pest management science》1999,55(4):467-473
In this study four different mixing/loading and application practices in potato fields were monitored for exposure of operators to pesticides. Each operation – mixing, loading, and application – was measured individually in order to assess its relative contribution to the total exposure value. Inhalation exposure was measured by trapping the pesticides with a sorbent tube while sampling the air around the operator's face. Dermal deposition, which was measured by means of cotton gloves on the hands and by attaching patches to the operator's clothing, was the main contributor to the total exposure. Dermal deposition on the hands during mixing and loading exceeded all other dermal values. The experimental results are compared with the results obtained by the exposure assessment model PHED V1.1. This model gives an underestimation of the levels of operator exposure during mixing, loading and application. © 1999 Society of Chemical Industry 相似文献