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81.
Beth A. Valentine DVM Barry J. Cooper BVSc PhD Amy E. Dietze DVM Drew M. Noden PhD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1988,2(3):109-112
Congenital diaphragmatic hernia, affecting both sexes, was present in five of 27 puppies from three father-daughter matings. A purebred Golden Retriever was the common sire. The defect occurred in the left dorsolateral portion of the diaphragm, suggesting failure of closure of the left pleuroperitoneal canal during embryonic development. These findings, and a previous report of a similar defect in neonatal puppies, are consistent with autosomal recessive inheritance of canine diaphragmatic defects. 相似文献
82.
Metastatic testicular embryonal carcinoma in a horse 总被引:1,自引:0,他引:1
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This paper examines the relationship of planning ideals of sharply defining edges between urban density and greenspace and alternative urban greening arrangements as they are manifested in a case study of exurban “lifestyle blocks” on the fringes of Christchurch, Aotearoa New Zealand. Exurban development outside Christchurch's urban growth boundary – called the “urban fence” – provides an example of tension between municipal attempts to curb sprawl and exurbanites’ desire to live in the dispersed settlements outside of urban boundaries. These struggles play out at different scales and in a range of different metropolitan contexts. This paper reports on the results of an ethnographic study of Christchurch urban fringe residents’ residential land-use narratives and practices. The paper focuses on landscape preferences and concerns of a sample of small-scale productive land users and explores the implications of their versions of urban greening in the context of policy visions for the urban edge. A political ecology interpretation highlights relationships in this case study between competing claims about fringe greening and fringe landscape practices. These contests over the landscapes of the urban edge illustrate ways that municipal and regional planning visions for the urban edge conflict with the ideals and practices of those residents and land use managers who might otherwise be some of the strongest supporters of urban greening initiatives. Competing discourses about the urban edge relate in different ways to concerns about abrupt urban containment and to practices that act on these concerns. I briefly discuss promising examples of edge greening in this case that may provide models for participatory management of contested and multi-use greenspace at the urban–rural fringe. 相似文献
85.
Jin L Valentine BA Baker RJ Löhr CV Gerlach RF Bildfell RJ Moerdyk-Schauwecker M 《Veterinary pathology》2008,45(3):369-374
A herpesvirus infection affecting mini Rex and crossbred meat rabbits was identified in a rabbitry in Alaska. Illness affected over half of the 55 rabbits on the premises, and 16 rabbits died or were euthanatized because of illness. Disease affected all ages from adults to nursing young and occurred over an approximately 2-month period. Clinical signs included conjunctivitis and periocular swelling, ulcerative dermatitis, progressive weakness, anorexia, respiratory distress, and abortion. Hemorrhagic dermatitis and panniculitis were associated with epidermal microvesicular degeneration, dermal and subcutaneous vascular necrosis, and thrombosis. Eosinophilic intranuclear inclusions consistent with herpesvirus were found within the epidermis and superficial follicular epithelium and within mesenchymal cells within the dermis and subcutis. Syncytial cells containing viral inclusions occurred within the epidermal and superficial follicular epithelium. Other findings were hemorrhagic necrosis of the myocardium with rare intranuclear inclusions within stromal cells, multifocal pulmonary hemorrhage, hemorrhage with sinus erythrophagocytosis in lymph nodes, and massive necrosis and fibrin deposition within red pulp of the spleen. A virus isolated from the skin produced syncytia, intranuclear inclusions, and cell lysis typical of herpesvirus in rabbit kidney cells in vitro. The viral isolate was characterized ultrastructurally as an enveloped virus with icosahedral nucleocapsids 100 nm diameter, consistent with a herpesvirus. 相似文献
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Probing soil physical and biological resilience data from a broad sampling of arable farms in Scotland 下载免费PDF全文
B. S. Griffiths P. D. Hallett T. J. Daniell C. Hawes G. S. Squire S. M. Mitchell S. Caul T. A. Valentine K. Binnie A. J. Adeloye R. Rustum I. Nevison 《Soil Use and Management》2015,31(4):491-503
Physical and biological soil stabilities (i.e. resistance and resilience) were measured on a range of arable farms across eastern Scotland under a range of management practices, with the objective of using a geographically restricted set of soils under similar land use to detect any underlying associations between soil stability, management factors and soil properties. Data were analysed using a combination of a stepwise fixed effects model selection within a linear mixed‐model framework (LMM) and neural network analysis using a Kohonen self‐organising map (KSOM). In general, physical and biological measures of stability were associated with both physical and biological soil properties, particularly bulk density, water retention characteristics, soil carbon and bacterial community structure. A strength of KSOM is its ability to fit more flexible models than the linear relationships of LMM. However, a weakness is that it does not have the ability of LMM to model the sampling design, which is likely to lead to overstating statistical significance. Consequently, KSOM identified more significant associations between soil properties and stability than LMM, while the latter identified significant associations at the between‐farm level. The high‐level land management decisions of farm type (conventional, organic, integrated), crop type or underlying soil type were not associated with stability at this regional scale, thus indicating that the effects of different management practices between farms were overridden by the soil properties on each farm. Management decisions on improving soil stability therefore need to be taken at the individual field scale. 相似文献
89.
David?L.?R.?AffleckEmail author Timothy?G.?Gregoire Harry?T.?Valentine 《Journal of Agricultural, Biological & Environmental Statistics》2005,10(4):460-477
Transects consisting of multiple, connected segments with a prescribed configuration are commonly used in ecological applications
of line intersect sampling. The transect configuration has implications for the probability with which population elements
are selected and for how the selection probabilities can be modified by the boundary of the tract being sampled. As such,
the transect configuration also affects the performance of methods designed to eliminate edge-effect bias. We show that the
reflection method solves the edge-problem for designs that use symmetric radial transects (e.g., straight-line and X-shaped
transects centered at the sample point). This method also applies to designs that use asymmetric radial transects, provided
the orientation is selected uniformly at random. Asymmetric radial transects include straight lines emanating from the sample
point, and L- and Y-shaped transects. The reflection method does not apply to designs where polygonal transects (e.g., triangular,
square, and hexagonal transects) are used, or where the orientations of asymmetric radial transects are fixed. We provide
a new method that eliminates edge-effect bias for designs that use asymmetric radial transects with fixed orientation, but
a workable solution for polygonal transects remains elusive. 相似文献
90.
B. A. Valentine M. B. Calderwood Mays H. S. Cheramie 《Equine Veterinary Education》2014,26(3):156-158
Information regarding signalment, clinical findings, treatment and outcome of 5 previously reported cases of anaplastic malignant melanoma of the tail in non‐grey horses and of 5 additional cases are summarised. Age was recorded for 9 horses and mean age was 16 years, range 8–23 years. Gender was recorded for 8 horses and 6 of these 8 horses were male horses over 14 years of age. The most common coat colour was bay (6 horses). Other coat colours were palomino (one horse), chestnut (one horse) and black (one horse); coat colour of one non‐grey horse was not specified. Follow‐up information was available for 9 horses and only one horse, a palomino, survived more than 10 months following diagnosis and tail amputation. Surgical excision, including tail amputation and medical therapy with oral cimetidine, was not effective in non‐grey, non‐palomino horses. Tumour recurred on tail tissue remaining after amputation in 2 horses, widespread metastases were documented in 4 cases and metastasis was suspected at the time of death or euthanasia in 3 cases, including one case with amputation site regrowth. No subjective histopathological differences were detected in the palomino horse that survived as compared to horses of other coat colours. Findings suggest that anaplastic malignant melanoma of the tail in non‐grey horses is most often a very aggressive neoplasm, but that there are rare exceptions. 相似文献