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排序方式: 共有279条查询结果,搜索用时 62 毫秒
91.
92.
Naaf Tobias Feigs Jannis Till Huang Siyu Brunet Jörg Cousins Sara A. O. Decocq Guillaume De Frenne Pieter Diekmann Martin Govaert Sanne Hedwall Per-Ola Helsen Kenny Lenoir Jonathan Liira Jaan Meeussen Camille Plue Jan Poli Pedro Spicher Fabien Vangansbeke Pieter Vanneste Thomas Verheyen Kris Holzhauer Stephanie I. J. Kramp Katja 《Landscape Ecology》2021,36(10):2831-2848
Landscape Ecology - Evidence for effects of habitat loss and fragmentation on the viability of temperate forest herb populations in agricultural landscapes is so far based on population genetic... 相似文献
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Journal of Pest Science - Host detection and parasitism by egg parasitoids involve host chemical recognition, spatial overlapping, and the ability to overcome physical barriers. Within the context... 相似文献
95.
Guillaume Laberge Per Ambus Henrik Hauggaard-Nielsen Erik Steen Jensen 《Soil biology & biochemistry》2006,38(7):1998-2000
The decline of N from 15N-labelled mature pea residues was followed in unplanted soil over 16.5 yr. Eight years after residue incorporation, 24% of the residue 15N input was still present in the soil and, after 16.5 yr, 16% of the residue 15N input remained. A double exponential model successfully described the decay of N from 15N-labelled pea residues. The total residual 15N declined with average decay constants of 1.45 yr−1 for the 30 d to 1 yr period and of 0.07 yr−1 for the 1-16 yr period. Sixteen years following incorporation of the residues, indicator plants growing in residues-amended soils were obtaining 1.7% of their N from residue N. This is, to our knowledge, the longest study on decay of N in soils from 15N-labelled crop residues. The current study thus provides a unique data set for our empirical understanding of N-dynamics in agricultural systems, which is a prerequisite to parameterize and validate N-simulation models. 相似文献
96.
Raj VS Fournier G Rakus K Ronsmans M Ouyang P Michel B Delforges C Costes B Farnir F Leroy B Wattiez R Melard C Mast J Lieffrig F Vanderplasschen A 《Veterinary research》2011,42(1):92
ABSTRACT: Cyprinid herpesvirus 3 (CyHV-3) is the aetiological agent of a mortal and highly contagious disease in common and koi carp. The skin is the major portal of entry of CyHV-3 in carp after immersion in water containing the virus. In the present study, we used in vivo bioluminescence imaging to investigate the effect of skin mucus removal and skin epidermis lesion on CyHV-3 entry. Physical treatments inducing removal of the mucus up to complete erosion of the epidermis were applied on a defined area of carp skin just before inoculation by immersion in infectious water. CyHV-3 entry in carp was drastically enhanced on the area of the skin where the mucus was removed with or without associated epidermal lesion. To investigate whether skin mucus inhibits CyHV-3 binding to epidermal cells, tail fins with an intact mucus layer or without mucus were inoculated ex vivo. While electron microscopy examination revealed numerous viral particles bound on the fins inoculated after mucus removal, no particle could be detected after infection of mucus-covered fins. Finally, anti-CyHV-3 neutralising activity of mucus extract was tested in vitro. Incubation of CyHV-3 with mucus extract reduced its infectivity in a dose dependent manner. The present study demonstrates that skin mucus removal and epidermal lesions enhance CyHV-3 entry in carp. It highlights the role of fish skin mucus as an innate immune protection against viral epidermal entry. 相似文献
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OBJECTIVE: To report outcome after surgical and interventional radiographic treatment of hepatic arteriovenous fistulae (HAVF) in dogs. STUDY DESIGN: Retrospective study. ANIMALS: Dogs (n=20) with HAVF. METHODS: Medical records of dogs with HAVF were reviewed. Referring veterinarians and owners were contacted by telephone. History, clinical signs, biochemical and hematologic variables, ultrasonographic and angiographic findings, surgical findings, techniques used to correct the HAVF, survival time, and clinical follow-up were recorded. RESULTS: Canine HAVF often appeared to be an arteriovenous malformation rather than a single fistula. Multiple extrahepatic portosystemic shunts were identified in 19 dogs. Surgery (lobectomy or ligation of the nutrient artery) and/or interventional radiology (glue embolization of the abnormal arterial vessels) was performed in 17 dogs. Thirteen dogs were treated by surgery alone, 4 dogs by glue embolization alone, and 1 dog by glue embolization and surgery. Three dogs treated by surgery alone died <1 month later, and 3 dogs were subsequently euthanatized or died because of persistent clinical signs. None of the dogs treated by glue embolization died <1month after the procedure and all were alive, without clinical signs, at follow-up (9-17 months). Overall, 9 of 12 (75%) dogs with long-term follow-up required dietary or medical management of clinical signs. CONCLUSION: HAVF-related death occurred less frequently after glue embolization than after surgery. CLINICAL RELEVANCE: Glue embolization may be a good alternative to surgery for treatment of certain canine HAVF. 相似文献
99.
Guis H Tran A de La Rocque S Baldet T Gerbier G Barragué B Biteau-Coroller F Roger F Viel JF Mauny F 《Veterinary research》2007,38(5):669-683
The recent and rapid spread in the Mediterranean Basin of bluetongue, a viral disease of ruminants transmitted by some species of Culicoides (biting midges), highlights the necessity of determining the conditions of its emergence. This study uses high spatial resolution satellite imagery and methods from landscape ecology science to identify environmental parameters related to bluetongue occurrence in Corsica, a French Mediterranean island where the disease occurred for the first time in 2000. A set of environmental variables recorded in the neighborhood of 80 sheep farms were related to case occurrence through a logistic regression model computed within three subsequent buffer distances of 0.5, 1 and 2 km. The results reveal the role of landscape metrics, particularly those characterizing land-use units such as prairies and woodlands, as well as farm type, latitude and sunshine to explain the presence of bluetongue. Internal and external validation both indicate that the best results are obtained with the 1 km buffer size model (area under Receiver Operating Characteristic curve = 0.9 for internal validation and 0.81 for external validation). The results show that high spatial resolution remote sensing (i.e. 10 m pixels) and landscape ecology approaches contribute to improving the understanding of bluetongue epidemiology. 相似文献