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排序方式: 共有546条查询结果,搜索用时 18 毫秒
101.
Matthias Vanmaercke Willem Maetens Jean Poesen Benediktas Jankauskas Genovaite Jankauskiene Gert Verstraeten Joris de Vente 《Journal of Soils and Sediments》2012,12(4):586-602
Purpose
This study aims to understand better the relationship between measured soil loss rates due to sheet and rill erosion (SL), predicted SL rates and measured catchment sediment yields (SY) in Europe. 相似文献102.
Jaine H. H. L. de Oliveira Mirna H. R. Seleghim Christoph Timm Achim Grube Matthias K?ck Gislene G.F. Nascimento Ana Claudia T. Martins Elissa G. O. Silva Ana Olívia de Souza Paulo R. R. Minarini Fabio C. S. Galetti Célio L. Silva Eduardo Hajdu Roberto G. S. Berlinck 《Marine drugs》2006,4(1):1-8
Cyclostellettamines A – F (1 – 6) isolated from the sponge Pachychalina sp. and cyclostellettamines G - I, K and L (7 – 11) obtained by synthesis were evaluated in bioassays of antimicrobial activity against susceptible and antibiotic-resistant Staphylococcus aureus, Pseudomonas aeruginosa and antibiotic-susceptible Escherichia coli and Candida albicans, as well as in antimycobacterial activity against Mycobacterium tuberculosis H37Rv bioassays. The results obtained indicated that cyclostellettamines display different antimicrobial activity depending on the alkyl-chain size, suggesting that, if a mechanism-of action is implied, it is dependent on the distance between the two pyridinium moieties of cyclostellettamines. 相似文献
103.
ABSTRACT: Single nucleotide polymorphisms (SNPs) in the genes for interleukin-4, -13 and interferon-gamma, and 21 additional SNPs which previously had been significantly associated with immune traits in the chicken, were genotyped in white and brown layer hens and analyzed for their association with helminth burden following natural infections. A nucleotide substitution located upstream of the promoter of the interferon-gamma gene was significantly associated with the log transformed number of Ascaridia galli in the brown layer line (genotype CC: 6.4 ± 1.0 worms; genotype CT: 11.7 ± 2.2 worms). Therefore, IFNG seems to be a promising candidate gene for further studies on helminth resistance in the chicken. 相似文献
104.
Völkel I Schmitz C Moors E Gauly M Czerny CP 《Berliner und Münchener tier?rztliche Wochenschrift》2011,124(1-2):71-77
During the fattening period of a broiler flock four different litter materials (peat, chopped straw, shavings, silage) were tested simultaneously.The separated sections were tested for the presence of Salmonella bacteria using the sock-sampling method as described in the regulation EC No. 646/2007 with slight modifications in the sampling technique and the laboratory protocol. In addition, some chemical and physical parameters regarding litter quality and house climate were analysed. Samples were taken at day 0 (housing of animals), day 14, and day 30. At the end of the fattening period Salmonella Paratyphi B (d-tartrate +), representing a common strain in German broiler flocks, were isolated from culture. According to the various types of bedding materials some differences in the frequency of Salmonella detection were found. With three samples out of six samples being positive, wood shavings showed the highest Salmonella prevalence, followed by peat with two positive results. Corn silage was found to be a suitable alternative for common litter materials and revealed only one positive sample. Chopped straw was found to be free of Salmonella in our study. However, the latter had a higher risk for negative side effects concerning animal health and house climate. The study showed that the choice of an appropriate litter material might be of considerable importance in order to decrease the Salmonella burden within poultry flocks. 相似文献
105.
Sünder U Moors E Hagemann K Gauly M 《Berliner und Münchener tier?rztliche Wochenschrift》2011,124(1-2):28-35
The aim of this study was to estimate the effects of flying insects (Order Diptera) on the behaviour of grazing horses in relation to the use of insecticide and repellent substances. The investigations were done between June and August in 2008 in 3 periods of 7 days each. As insecticide and repellent two substances were used: "Well-care emulsion" (Co. Essex Tierarznei, München, GER) containing Permethrin and "Bremsen-Frei-Plus" (Co. Dr. Schaette AG, Bad Waldsee, GER) based on etheric oils. Both groups were compared with a non treated control group in a crossover-design. Each group (n = 3-5) was used alternately as control and treatment group. Several climate parameters were taken during the study. Furthermore, the number of insects per animal was estimated at certain times. Once per observation period insects were caught using Malaise traps and differentiated by species. The proportion of horse relevant species of the genera Diptera, especially Culex pipiens and Musca autumnalis, caught was 9% on an average. There was no correlation between the number of Tabanidae caught in the Malaise traps and the number observed near by the horses. Behaviour parameters like tailswishing, headshaking, stamping, skintwitching, snapping at the body, and moving were observed more frequently with increasing insect infestation. When horses were infested with a high number of flying insects, feeding activity was significant lower, whereas locomotion activity was significant higher. Both substances had positive effects for about 50 hours after application with no apparent difference between the substances. However, a lower frequency of headshaking and tailswishing could be observed in the Permethrin treated horses. 相似文献
106.
Wolf D Lüpke M Wefstaedt P Klopmann T Nolte I Seifert H 《Acta veterinaria Hungarica》2011,59(1):53-68
The aim of this study was to develop an examination protocol for magnetic resonance imaging, in order to display diagnostically important information of the canine middle and inner ear. To ensure that this protocol could also be used as a basis for determining pathological changes, the anatomical structures of the ear were presented in detail. To minimise stress through anaesthesia in live animals, preliminary examinations were carried out on four dog cadavers. During these initial examinations, three-dimensional (3D) sequences proved to be superior to two-dimensional ones. Therefore, only 3D sequences were applied for the main examinations performed on six clinically healthy Beagles. The anonymised MR images were rated by three experienced reviewers using a five-point scale. The most valuable sequence was a T2-weighted CISS sequence (TR = 16.7 ms, TE = 8.08 ms). This sequence proved to be most suitable for illustrating the inner ear structures and enabled good tissue contrasts. The sequence ranked second best was also a T2-weighted DESS sequence (TR = 19 ms, TE = 6 ms), allowing the imaging of the tympanic cavity and enabling 3D reconstruction due to its isotropic voxels. Due to low contrast and strong noise, the other sequences (TSE, FISP, MP RAGE) were not suitable for anatomical illustration of the middle and inner ear. 相似文献
107.
108.
Neringa Alisauskaite Katrin Beckmann Matthias Dennler Niklaus Zölch 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2020,34(4):1594-1598
Cortical atrophy has been identified using magnetic resonance imaging (MRI) in humans and dogs with Lafora disease (LD). In humans, proton magnetic resonance spectroscopy (1HMRS) of the brain indicates decreased N-acetyl-aspartate (NAA) relative to other brain metabolites. Brain 1HMRS findings in dogs with LD are lacking. A 6-year-old female Beagle was presented with a history of a single generalized tonic-clonic seizure and episodic reflex myoclonus. Clinical, hematological, and neurological examination findings and 3-Tesla MRI of the brain were unremarkable. Brain 1HMRS with voxel positioning in the thalamus was performed in the affected Beagle. It identified decreased amounts of NAA, glutamate-glutamine complex, and increased total choline and phosphoethanolamine relative to water and total creatine compared with the reference range in healthy control Beagles. A subsequent genetic test confirmed LD. Abnormalities in 1HMRS despite lack of changes with conventional MRI were identified in a dog with LD. 相似文献
109.
Hydrothermal carbonization (HTC) is a method to produce carbonized material at relatively low temperatures (180–250 °C) under pressure and aqueous conditions. The product is called hydrochar and can be used as a soil amendment. However, applied in high dosages it may have detrimental effects on plants or soil biota. The potential impact of hydrochar amendment on beneficial soil organisms such as arbuscular mycorrhizal fungi (AMF) and earthworms and their interactions are not well understood. The goal of the present study was to determine effects of hydrochar on plant growth and soil biota and to evaluate interactions of earthworms and hydrochar on plant and AMF performance and to identify underlying mechanisms. In a greenhouse experiment, we investigated the effect of hydrochar at different addition rates (control, 1% and 10%, v/v) with or without the earthworm Aporrectodea caliginosa on the growth of Plantago lanceolata L. and the performance of its AMF. We observed a positive interaction between earthworms and 10% hydrochar on shoot and root biomass: added as a single treatment hydrochar had a negative effect on plant growth at this dosage, but plant biomass increased significantly when hydrochar was added together with earthworms. Root colonization by AMF increased significantly with increasing concentration of hydrochar, but was not affected by earthworms. Contrastingly, extraradical hyphal length of AMF was reduced by earthworms, but not affected by hydrochar. Thus, hydrochar and earthworms affected the performance of AMF, albeit of different AMF structures and in different directions. Our results indicate that earthworms may play an important role in alleviating the negative impacts of high dosages of hydrochar on plant growth; such interactions should move into focus of future research on potential effects of HTC materials. 相似文献
110.
In this study we demonstrate that the demosponge Suberites domuncula harbors a Mn(II)-oxidizing bacterium, a Bacillus strain, termed BAC-SubDo-03. Our studies showed that Mn(II) stimulates bacterial growth and induces sporulation. Moreover, we show that these bacteria immobilize manganese on their cell surface. Comparison of the 16S rDNA sequence allowed the grouping of BAC-SubDo-03 to the Mn-precipitating bacteria. Analysis of the spore cell wall revealed that it contains an Mn(II)-oxidizing enzyme. Co-incubation studies of BAC-SubDo-03 with 100 μM MnCl(2) and >1 μM of CuCl(2) showed an increase in their Mn(II)-oxidizing capacity. In order to prove that a multicopper oxidase-like enzyme(s) (MCO) exists in the cell wall of the S. domuncula-associated BAC-SubDo-03 Bacillus strain, the gene encoding this enzyme was cloned (mnxG-SubDo-03). Sequence alignment of the deduced MCO protein (MnxG-SubDo-03) revealed that the sponge bacterium clusters together with known Mn(II)-oxidizing bacteria. The expression of the mnxG-SubDo-03 gene is under strong control of extracellular Mn(II). Based on these findings, we assume that BAC-SubDo-03 might serve as a Mn reserve in the sponge providing the animal with the capacity to detoxify Mn in the environment. Applying the in vitro primmorph cell culture system we could demonstrate that sponge cells, that were co-incubated with BAC-SubDo-03 in the presence of Mn(II), show an increased proliferation potential. 相似文献