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81.
Unlike farm animals, wild animals are not subject to continuous health surveillance. Individual projects designed to screen wildlife populations for specific pathogens are, therefore, also of great importance for human health. In this context, the possible formation of a reservoir for highly pathogenic zoonotic pathogens is a focus of research. Two of these pathogens that have received particular attention during the last years are the novel severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), due to its fast global spread and high impact to the human health, and, since its introduction into Germany, the flavivirus West Nile virus (WNV). Especially in combination with invasive vertebrate species (e.g., raccoons (Procyon lotor) and raccoon dogs (Nyctereutes procyonoides) in Germany), risk analysis must be done to enable health authorities to assess the potential for the establishment of new wild life reservoirs for pathogens. Therefore, samples were collected from raccoons and raccoon dogs and analyzed for the presence of SARS-CoV-2 and WNV infections in these populations. Molecular biological and serological data obtained imply that no SARS-CoV-2 nor WNV reservoir has been established in these two wild life species yet. Future investigations need to keep an eye on these invasive carnivore populations, especially since the close contact of these animals to humans, mainly in urban areas, would make animal–human transmission a challenge for human health.  相似文献   
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Effectively managing and optimizing the value of the patent portfolio is a major challenge for many firms, especially those in knowledge intensive industries, such as the pharmaceutical, biotechnological and chemical industry. However, insights on effective patent portfolio strategies are rare. Therefore, in this article we investigate in detail how firms successfully manage and optimize their patent portfolios to increase their overall competitiveness. We discover that successful patent portfolio management is rooted in managing the patents along their life cycles. Based on the findings of ten case studies, we develop a holistic patent life cycle management model reflecting five distinctive phases of patent management: explore, generate, protect, optimize and decline. We conclude with how our findings can be used in practice.  相似文献   
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West Nile virus (WNV) is an emerging infectious pathogen circulating between mosquitoes and birds but also infecting mammals. WNV has become autochthonous in Germany, causing striking mortality rates in avifauna and occasional diseases in humans and horses. We therefore wanted to assess the possible role of free-ranging poultry in the WNV transmission cycle and infected 15 goslings with WNV lineage 2 (German isolate). The geese were monitored daily and sampled regularly to determine viremia, viral shedding, and antibody development by molecular and serological methods. Geese were euthanized at various time points post-infection (pi). All infected geese developed variable degrees of viremia from day 1 to day 10 (maximum) and actively shed virus from days 2 to 7 post-infection. Depending on the time of death, the WN viral genome was detected in all examined tissue samples in at least one individual by RT-qPCR and viable virus was even re-isolated, except for in the liver. Pathomorphological lesions as well as immunohistochemically detectable viral antigens were found mainly in the brain. Furthermore, all of the geese seroconverted 6 days pi at the latest. In conclusion, geese are presumably not functioning as important amplifying hosts but are suitable sentinel animals for WNV surveillance.  相似文献   
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Ohne Zusammenfassung Mit 5 Abbildungen  相似文献   
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