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排序方式: 共有802条查询结果,搜索用时 15 毫秒
141.
Wohlsein P Lehmbecker A Spitzbarth I Algermissen D Baumgärtner W Böer M Kummrow M Haas L Grummer B 《Veterinary microbiology》2011,149(3-4):456-460
In a zoological collection, four black bears (Ursus americanus) died from neurological disease within six months. Independently in a geographically different zoo, two Thomson's gazelles (Eudorcas thomsoni) and 18 guinea pigs (Cavia porcellus f. dom.) suffered from neurological disorders. In addition, guinea pigs showed abortions and stillbirths. All affected animals displayed a non suppurative meningoencephalitis with intranuclear inclusion bodies. Immunohistology demonstrated equine herpes virus antigen and ultrastructurally herpes viral particles were detected. Virus isolation and molecular analysis identified neurotropic equine herpesvirus (EHV) 1 strains in both epizootics. There is serological evidence of a possible virus transmission from other equids to the affected animals. Cross-species transmission of EHV-1 should be considered in the management of captive wild equids and ungulates, particularly with respect to fatal disease in irreplaceable species. 相似文献
142.
Wisner AL Desin TS Lam PK Berberov E Mickael CS Townsend HG Potter AA Köster W 《Veterinary microbiology》2011,153(3-4):274-284
Several structural components of the type III secretion systems (T3SS) encoded by Salmonella pathogenicity island (SPI)-1 and SPI-2 are exposed to the host's immune system prior to/during the infection/invasion process, making them potential vaccine candidates. In this study we evaluated whether chickens vaccinated with SPI-2 T3SS components could mount a significant humoral immune response (as measured by serum IgG titres) and whether these antibodies could be transferred to progeny (as measured by egg yolk IgG titres), and whether vaccinates and progeny of vaccinates could be protected against challenge with SE. The results of our studies show that vaccinated chickens do produce high levels of SPI-2 T3SS specific serum IgG that they are able to transfer to their progeny. It was demonstrated that vaccinates and progeny of vaccinates had lower overall countable recovered Salmonella enterica subspecies enterica serovar Enteritidis (SE) per bird in most situations. 相似文献
143.
Contents and bioavailability of rare earth elements in agricultural soils in Hesse (Germany) 总被引:2,自引:0,他引:2
With increasing agricultural and industrial use of rare earth elements (REEs), input of REEs into the pedosphere has risen in parallel. Since total REE budgets for soils in Germany are mainly unknown, this pilot study investigates the concentrations of REEs in three loess soil profiles under agricultural land use in the Wetterau region, Germany. There were no significant REE applications in the past, so the presented data can be considered as background concentrations of REEs in soils. In addition to the total REE contents (aqua regia digestion), potentially plant‐available (EDTA) and at actual conditions available, mobile (NH4NO3) REEs have been determined for each horizon. Interactions between REE availability and properties of soils are explained after assessing several chemical and physical properties. The results reveal a wide range of total REE contents, ranging from 222 to 423 mg kg–1. With 10.1% of total REE amounts, the potentially plant‐available proportions of REEs are generally low. In contrast, yttrium, which showed high available proportion of 24.8%, was found to be comparable with Cd. Cerium is the most abundant REE in aqua regia digests, whereas only small amounts in the potentially plant‐available fraction were found. Thus negative cerium anomalies could be concluded concerning its potential availability. Generally, bioavailability of REE had significant correlations between clay contents and Fe and Mn oxides for the majority of REEs. Due to moderately high pH (CaCl2) in soils (average 6.6) the mobile fraction for most of the elements was not detectible. 相似文献
144.
Barnsteiner A Lubinus T di Gianvito A Schmid W Engel KH 《Journal of agricultural and food chemistry》2011,59(10):5204-5214
Approaches for the capillary gas chromatographic (GC) based analysis of intact plant stanyl esters in enriched foods were developed. Reference compounds were synthesized by enzyme-catalyzed transesterifications. Their identities were confirmed by means of mass spectrometry. Using a medium polar trifluoropropylmethyl polysiloxane stationary phase, long-chain plant stanyl esters could be separated according to their stanol moieties and their fatty acid chains. Thermal degradation during GC analysis was compensated by determining response factors; calibrations were performed for ten individual plant stanyl esters. For the analysis of low-fat products (skimmed milk drinking yogurts), the GC separation was combined with a "fast extraction" under acidic conditions. For fat-based foods (margarines), online coupled LC-GC offered an elegant and efficient way to avoid time-consuming sample preparation steps. The robust and rapid methods allow conclusions on both, the stanol profiles and the fatty acid moieties, and thus provide a basis for the authentication of this type of functional food ingredients. 相似文献
145.
Heinz Benkenstein Michael Baumecker Hans Pagel Wolfgang Krüger 《Archives of Agronomy and Soil Science》2013,59(6):523-538
Langjährig unterlassene Kalkung führte bei mineralisch (NPK) und mit Stallmist gedüngtem Boden in den letzten 20 Versuchsjahren zu pH‐Werten von 4,2 bis 3,6. Die Relativerträge nahmen im Vergleich zur mineralischen Volldüngung (NPKCa) ab. Diese Abnahme war von der Pflanzenart abhängig und bei Sommergerste deutlicher als bei Kartoffeln und Mais. Kalkung des mit NPK gedüngten Bodens erhöhte die Erträge bei Mais bereits im ersten Jahr, bei Gerste und Kartoffeln erst nach mehreren Jahren auf das Niveau der Vergleichsvariante. Bei einer Umstellung von Stallmist auf Stallmist + NPKCa glichen sich die Erträge von Mais und Sommergerste im gleichen Jahr, bei Kartoffeln erst nach mehreren Jahren dem langjährig mit Stallmist + NPKCa gedüngten Prüfglied an. Im langjährig ungedüngten Boden fielen pH‐Wert, KDL und PDL in den letzten 20 Versuchsjahren ebenfalls deutlich ab (pH 3,6 bis 4,1; KDL 2,2 bis 5,0 und PDL 3,5 bis 5,5 mg/100 g Boden). In deren Folge und durch N‐Mangel kam es bei Gerste zum Totalausfall und bei Mais nahezu zum Totalausfall. Bei Kartoffeln lag der Ertrag noch bei 15% der Vergleichsvariante NPKCa. Eine Düngung der Mangelparzellen mit NPKCa ließ den pH‐Wert bereits im ersten Jahr, KDL und PDL erst nach mehrmaliger Düngung in den anzustrebenden Bereich ansteigen. Eine Angleichung der Erträge an die Erträge des durchgehend mit NPKCa gedüngten Prüfgliedes dauerte drei bis vier Jahre. 相似文献
146.
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149.
Dr. Wolfgang Müller Dr. Klaus Fricke Prof. Dr. Hardy Vogtmann 《Compost science & utilization》2013,21(3):42-52
The German Technical Guideline for Municipal Solid Waste (TASI) stipulates criteria for waste to be landfilled in order to minimize environmental hazards and landfill maintenance. One of these requirements is an ignition loss of less than five percent dm (dry matter). Only waste which has been incinerated can comply with this criterion, and subsequently be landfilled. Experts agree that the ignition loss alone is not suitable to predict reactions in a landfill. Therefore, other methods of assessing biological activity of processed MSW in a landfill are presented and discussed. It was found that respiration activity was most appropriate for such an assessment at this stage. From available data, it was concluded that processed MSW is fit for landfilling if the respiration activity is below 5 mg O2/g dm over a period of 96 hours. 相似文献
150.
Michael Zech Mario Tuthorn Bruno Glaser Wulf Amelung Bernd Huwe Wolfgang Zech Ludwig Zöller Jörg Löffler 《植物养料与土壤学杂志》2013,176(1):12-15
Precipitation and topsoil samples from a climate transect over the Scandinavian Mountains, Norway, were analyzed for bulk and compound‐specific δ18O values. The natural abundance of 18O in the plant‐derived hemicellulose biomarkers arabinose and xylose correlates positively with δ18O of bulk soil, but not with δ18O of precipitation. This suggests that other factors than δ18Oprec, such as evaporative 18O enrichment of leaf water, exert a strong influence on the natural abundance of 18O in soils. 相似文献