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The goal of this study was to establish Magnetic resonance imaging (MRI) reference ranges for spinal measurements in normal dogs. Forty dogs (1–10 kg, 11–20 kg, 21–30 kg, > 30 kg; 10 dogs per category) underwent spinal MRI. Measurements were performed on sagittal T2‐W images at the level of the 4th thoracic vertebra (T4), the 9th thoracic vertebra (T9) and the 3rd lumbar vertebra (L3). Spinal canal diameter (mm) ranged from 6.07 ± 0.63 (1–10 kg) to 8.27 ± 1.15 (> 30 kg) at the level of T4; 6.55 ± 0.61 (1–10 kg) to 9.04 ± 1.26 (> 30 kg) at the level of T9; and 6.80 (6.47–7.00; 1–10 kg) to 9.00 (7.90–9.73; > 30 kg) at the level of L3. There were significant differences (P < 0.05) in spinal canal diameter between groups. Mean spinal cord diameter (mm) ranged from 4.46 ± 0.51 (11–20 kg) to 4.70 ± 0.35 (1–10 kg) at the level of T4; 4.41 ± 0.50 (> 30 kg) to 4.85 ± 0.57 (1–10 kg) at the level of T9; and 4.52 ± 0.51 (> 30 kg) to 5.14 ± 0.68 (1–10 kg) at the level of L3. There were no significant differences in spinal cord diameter between groups. Spinal cord‐to‐spinal canal ratio varied significantly, ranging from 0.51 ± 0.08 (> 30 kg at L3) to 0.78 (0.69–0.80; 1–10 kg at T4) (P < 0.05). These findings are important when using MRI to evaluate patients with suspected diffuse spinal cord disease.  相似文献   
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North American temperate grasslands and the wildlife species they support are increasingly imperilled, largely due to habitat loss and degradation. Most remaining prairie is privately managed and supports livestock production. In Canada, voluntary stewardship is the preferred approach for protecting species at risk on private lands under the federal Species at Risk Act (SARA). However, attitudes of private land managers toward species at risk and their willingness to engage in stewardship are poorly understood. With data from interviews with 42 livestock producers in Saskatchewan, Canada, we describe producer characteristics, attitudes, and awareness of species at risk and evaluate how these factors influence willingness to protect species at risk. Younger producers with increased formal education, awareness, and positive attitudes were more willing to support conservation of species at risk. Voluntary stewardship under the SARA may be enhanced by rewarding producers for sound habitat management and improving trust between producers and government agencies.  相似文献   
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Hurricanes Katrina and Rita showed the vulnerability of coastal communities and how human activities that caused deterioration of the Mississippi Deltaic Plain (MDP) exacerbated this vulnerability. The MDP formed by dynamic interactions between river and coast at various temporal and spatial scales, and human activity has reduced these interactions at all scales. Restoration efforts aim to re-establish this dynamic interaction, with emphasis on reconnecting the river to the deltaic plain. Science must guide MDP restoration, which will provide insights into delta restoration elsewhere and generally into coasts facing climate change in times of resource scarcity.  相似文献   
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