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Background
Pelodera (Rhabditis) strongyloides is a small saprophytic nematode that lives in decaying organic matter. On rare occasions, it can invade the mammalian skin, causing a pruritic, erythematous, alopecic and crusting dermatitis on skin sites that come into contact with the ground. Diagnosis of the disease is based on case history (a dog living outdoors on damp straw bedding) with characteristic skin lesions and on the demonstration of typical larvae in skin scrapings or biopsy. Pelodera (rhabditic) dermatitis cases have been reported mainly from Central European countries and the United States. 相似文献404.
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406.
Robert J. Hetherington 《BMJ (Clinical research ed.)》1965,2(5466):879-880
407.
Clive A. McAlpine John Callaghan Daniel Lunney Jonathan R. Rhodes Ross Goldingay Will Goulding Christine Adams-Hosking Kelly Fielding Scott Benitez Hetherington Angie Brace Marama Hopkins Liz Caddick Elisha Taylor Lorraine Vass Linda Swankie 《Austral ecology》2023,48(5):928-951
Conserving habitats crucial for threatened koala (Phascolarctos cinereus) populations requires rating habitat quality from a fine spatial scale to patches, landscapes and then regions. The koala has a specialized diet focused on the leaves of a suite of Eucalyptus species. We asked: what are the key regional influences on habitat selection by koalas in the far north coast of New South Wales? We addressed this question by investigating the multi-scale factors, and within-scale and cross-scale interactions, that influence koala habitat selection and distribution across four local government areas on the far north coast of New South Wales. We assembled and analysed a large data set of tree selection, identified by the presence of scats, in a wide range of randomly selected 5 × 5 km grids across the region. This resulted in more than 9000 trees surveyed for evidence of koala use from 302 field sites, together with associated biophysical site features. The dominant factor influencing habitat use and koala occurrence was the distribution of five Eucalyptus species. Koalas were more likely to use medium-sized trees of these species where they occurred on soils with high levels of Colwell phosphorous. We also identified new interactions among the distribution of preferred tree species and soil phosphorous, and their distribution with the amount of suitable habitat in the surrounding landscape. Our study confirmed that non-preferred species of eucalypts and non-eucalypts are extensively used by koalas and form important components of koala habitat. This finding lends support to restoring a mosaic of koala-preferred tree species and other species recognized for their value as shelter. Our study has provided the ecological foundation for developing a novel regional-scale approach to the conservation of koalas, with adaptability to other wildlife species. 相似文献
408.
Leon S. Rosenblatt Moshe Shifrine Norriss W. Hetherington Theresa Paglierioni Malcolm R. MacKenzie 《Biological Rhythm Research》2013,44(1):81-88
Abstract Rubella antibody titers were assayed from 191 blood samples taken during seven years (1973–1979) from a human female who had contracted German measles in 1965. The antibody dilutions, transformed to integers, fit a first‐order harmonic function with an assumed period of 365 days. The levels about which the titers oscillated decreased from 1973 to 1975 and remained stable thereafter. Amplitudes averaged 31% on either side of the level of oscillation. At certain times of the years 1977–1979 at the trough of the rhythm the subject would have been considered to be lacking in immunity against rubella despite history to the contrary. This example of a long‐term, circannual rhythm in an immunologic assay supports previous suggestions that immunity cycles over the seasons. 相似文献
409.
Bases and spaces: resources on the web for accessing the draft human genome - II - After publication of the draft 下载免费PDF全文
Colin AM Semple 《Genome biology》2001,2(6):reviews2001.1-reviews20016
The volume of human genome sequence and the variety of web-based tools to access it continue to grow at an impressive rate, but a working knowledge of certain key resources can be sufficient to get the most from your genome. This article provides an update to Genome Biology 2000, 1(4):reviews2001.1-2001.5. 相似文献
410.
Bracken (Pteridium aquilinum) is aggressively displacing heather (Calluna vulgaris) on many moorlands in Britain. We investigated the use of lignin derivatives to identify the distribution of soil organic
matter (SOM) derived from bracken in moorland soil profiles formed under heather. Phenylpropanoids extracted from recently
senesced litters, roots and SOM, using alkaline CuO oxidation, showed distinct signatures for bracken and heather, with vanillyl
moieties dominating bracken litter extracts and vanillyl and syringyl dominating heather litter extracts. Ratios of vanillyl
and syringyl concentrations characterised the SOM derived from heather and bracken better than the concentrations of the individual
moieties. The analysis showed up to a depth of 5 cm under pure bracken cover, and at the interface between heather and bracken,
the SOM was largely derived from bracken litter but below that depth SOM was apparently derived from heather. The use of these
methods to identify the plant origin of SOM not only enables understanding the effects of changing vegetation cover on organic
matter dynamics in moorland soils but could also facilitate management techniques in moorland/heathland restoration which
involve the removal of comparatively nutrient-rich SOM derived from bracken.
Received: 30 November 1997 / Accepted: 11 April 1998 相似文献