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Stephen Joslyn Suzanna Richards Susanne Boroffka Mark Mitchell Gawain Hammond Martin Sullivan 《Veterinary radiology & ultrasound》2014,55(1):63-67
Enhancement of extra‐ocular muscles has been reported in cases of orbital pathology in both veterinary and medical magnetic resonance imaging. We have also observed this finding in the absence of orbital disease. The purpose of this retrospective study was to describe extra‐ocular muscle contrast enhancement characteristics in a group of dogs with no known orbital disease. Magnetic resonance images (MRI) from dogs with no clinical evidence of orbital disease and a reportedly normal MRI study were retrieved and reviewed. Contrast enhancement percentages of the medial, lateral, ventral, and dorsal rectus muscles were calculated based on signal‐to‐noise ratios that were in turn determined from hand‐traced regions of interest in precontrast, immediate postcontrast and 10‐min postcontrast scans. Comparison measurements were made in the pterygoid muscle. Contrast enhancement of the extra‐ocular muscles was observed in all patients (median contrast enhancement percentage 45.0%) and was greater than that of pterygoid muscle (median contrast enhancement percentage 22.7%). Enhancement of the extra‐ocular muscles persisted 10 min after contrast administration (median contrast enhancement percentage 43.4%). Findings indicated that MRI contrast enhancement of extra‐ocular muscles is likely normal in dogs. 相似文献
35.
Sulfated polysaccharides (SP) from algae are of great interest due to their manifold biological activities. Obstacles to commercial (especially medical) application include considerable variability and complex chemical composition making the analysis and the quality control challenging. The aim of this study was to evaluate a simple microplate assay for screening the quality of SP. It is based on the fluorescence intensity (FI) increase of the sensor molecule Polymer-H by SP and was originally developed for direct quantification of SP. Exemplarily, 65 SP batches isolated from the red alga Delesseria sanguinea (D.s.-SP) and several other algae polysaccharides were investigated. Their FI increase in the Polymer-H assay was compared with other analytical parameters. By testing just one concentration of a D.s.-SP sample, quality deviations from the reference D.s.-SP and thus both batch-to-batch variability and stability can be detected. Further, structurally distinct SP showed to differ in their concentration-dependent FI profiles. By using corresponding reference compounds, the Polymer-H assay is therefore applicable as identification assay with high negative predictability. In conclusion, the Polymer-H assay showed to represent not only a simple method for quantification, but also for characterization identification and differentiation of SP of marine origin. 相似文献
36.
We examined collembolan food preference for fungal mycelium grown on copper-contaminated medium, and the relationship between copper content, food selectivity and collembolan fitness when fed contaminated mycelium.To clarify whether collembolan food selectivity is related to fitness parameters, Folsomia candida were fed mycelium of the dark-pigmented fungus Alternaria alternata grown on medium with different copper concentrations. Copper-contaminated food (fungus grown on 50, 125, 250 and 500 μg Cu g−1 medium, fresh wt.) was offered together with untreated food for 4 weeks. F. candida fed selectively on the provided mycelium and discriminated clearly between mycelium grown on high and low levels of contamination, distinctly preferring fungus grown on medium with a total copper concentration of 50 and 125 μg g−1. In contrast, fungus grown on highly contaminated medium (250 and 500 μg g−1) was avoided. Collembolan food preference generally matched fitness parameters. Reproduction was significantly affected by the total copper concentration of the fungal growth medium. When fed their preferred mycelium, collembolan reproduction was enhanced, whereas a diet of highly contaminated mycelium (250 or 500 μg g−1) resulted in a strong decrease in reproduction. Adult survival was affected only marginally. Even though heavy metal contamination is a potential stress factor for many soil microarthropods, F. candida is able to discriminate between high and low quality food sources, and even benefits from moderately elevated copper concentrations. 相似文献
37.
Different thermal treatments or processes (combustion, welding, thermowood) of several wood species were examined and compared. Each procedure resulted in different temperature loads on wood. The changes of lignin after thermal treatments were determined by different suitable methods, both wet chemical and instrumental analyses.The characterisation of the wood meals by means of FTIR spectroscopy has shown that changes of the aromatic skeletal vibrations occur, which indicate condensation reactions of lignin. The variations within the FTIR spectra of hardwood were more evident than those of softwood.The decomposition of lignin has also been proven in the acetone extracts of “thermowood”, which contained a lignan, identified by GC/MS.Moreover, the thioacidolysis showed the decrease of monomeric degradation products in all thermal treated samples. This is due to the cleavage of structural units bound by arylgycerol-β-ether linkages.However, it can be assumed that in addition to the degradation of specified types of bonds also condensation reactions have occurred and these products were not detectable by means of GC/MS. This conclusion would also support the above-mentioned results of FTIR spectroscopy. 相似文献
38.
D. L. Baggesen H. C. Wegener F. Bager H. Stege J. Christensen 《Preventive veterinary medicine》1996,26(3-4):201-213
As a part of a nationwide programme to survey and control salmonella in pig herds, a microbiological survey of 1363 pig herds was performed in Denmark. A total of 13 468 slaughter pigs were examined at slaughter by culture of 5 g of caecal contents. Overall, 30 different serotypes of Salmonella enterica were isolated from 832 pigs (6.2%). The predominant serotype was S. Typhimurium, comprising 536 (64.4%) of the isolates. Four hundred and forty-eight isolates of S. Typhimurium were examined by phage typing, resulting in detection of 17 different phage types (definitive types, DT) with DT12 being the most frequent (49.1%).
Salmonella enterica was found in 302 herds (22.2%), S. Typhimurium was found in 61.1% of these. 279 (23.1%) large herds (producing more than 2600 slaughter pigs per year) were found to be salmonella positive compared with 23 (14.7 %) small herds (annual production of 500 to 550 slaughter pigs). Practical constraints in the study design did not allow for a firm conclusion on the interplay among herd size, geographical location and occurrence of salmonella.
In 284 of 302 infected herds (94.0%) only one serotype was detected. Infections with two different serovars were seen in 18 herds (6.0%). 相似文献
39.
Ulrich?F?rstnerEmail author Susanne?Heise René?Schwartz Bernhard?Westrich Wolfgang?Ahlf 《Journal of Soils and Sediments》2004,4(4):247-260
Background, Aims, and Scope
Data from the Elbe River and its tributaries indicate, despite extensive improvement in water quality during the last 15 years, that the respective sediment situation of many priority pollutants has not reached an acceptable level. For the coming decades, risks for downstream sites and stakeholders will persist, mainly due to secondary sources originating from historical pollution of soils and sediments in the catchment area. In practice, a catchment-wide assessment of historical contaminated soil and sediment should apply a three-step approach: (i) Identification of substances of concern (s.o.c.) and their classification into ’hazard classes of compounds’; (ii) identification of areas of concern (a.o.c.) and their classification into ‘hazard classes of sites’; (iii) identification of areas of risk (a.o.r.) and their assessment relative to each other with regard to the probability of polluting the sediments in the downstream reaches. The conversion of this concept has to consider the underlying philosophy of the EU Water Framework Directive, particularly with respect to the analysis and monitoring of priority substances in solid matrices. However, major deficiencies are still in the assessment and prognosis of resuspension processes, and potential approaches to fill this gap are described both in theory and from examples of the Elbe River. 相似文献40.
Grassmann J Hippeli S Vollmann R Elstner EF 《Journal of agricultural and food chemistry》2003,51(26):7576-7582
The essential oil from Pinus mugo (PMEO) was tested on its antioxidative capacity. For this purpose, several biochemical test systems were chosen (e.g., the Fenton System, the xanthine oxidase assay, or the copper-induced oxidation of low-density lipoprotein (LDL)). The results show that there is moderate or weak antioxidative activity when tested in aqueous environments, like in the Fenton system, xanthine oxidase induced superoxide radical formation, or in the HOCl driven fragmentation of 1-aminocyclopropane-1-carboxylic acid (ACC). In contrast, when tested in more lipophilic environments (e.g., the ACC-cleavage by activated neutrophils in whole blood) the PMEO exhibits good antioxidative activity. PMEO does also show good antioxidative capacity in another lipophilic test system (i.e., the copper induced oxidation of LDL). Some components of PMEO (i.e., Delta(3)-carene, camphene, alpha-pinene, (+)-limonene and terpinolene) were also tested. As the PMEO, they showed weak or no antioxidant activity in aqueous environments, but some of them were effective antioxidants regarding ACC-cleavage by activated neutrophils in whole blood or copper-induced LDL-oxidation. Terpinolene, a minor component of PMEO, exhibited remarkable protection against LDL-oxidation. 相似文献