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91.
Martin DM Hall J Keirstead N Lowe A 《The Canadian veterinary journal. La revue veterinaire canadienne》2006,47(4):360-362
A 10-year-old, spayed female, obese golden retriever, presented for immune-mediated thrombocytopenia, was successfully managed with the administration of vincristine and prednisone. However, 6 mo after discontinuing corticosteroid therapy because of suspected iatrogenic hyperglucocorticoidism, the patient was presented with multiple, firm, bilaterally symmetric, dermal masses composed histologically of differentiated cortical bone. 相似文献
92.
93.
A study was conducted in an agricultural field to examine the biomass production of three fast-growing short rotation woody
crop (SRWC) species, Populus deltoides, Quercus pagoda, and Platanus occidentalis using fertilization and irrigation (fertigation). The study included a randomized complete block (RCB) with five treatments;
control, irrigated, and irrigated with 56, 112, and 224 kg nitrogen (N) ha−1 year−1. We quantified survival, basal area, standing biomass, aboveground net primary productivity (ANPP), leaf area index (LAI),
and growth efficiency (GE) for each species along the soil nitrogen and water gradient. P. deltoides had low rates of survival (83, 82, and 77% years six, seven, and eight, respectively), but had production values greater
than Q. pagoda and P. occidentalis. Standing biomass reached its peak for P. deltoides and P. occidentalis (17.56 and 10.36 Mg ha1, respectively) in the irrigation treatment, and in the 112 kg N treatment for Q. pagoda (5.42 Mg ha−1). P. deltoides and P. occidentalis ANPP peaked in the irrigation treatment (6.66 and 6.31 Mg ha−1 year−1, respectively) and in the 112 kg N (4.43 Mg ha−1 year−1) for Q. pagoda. ANPP was correlated with LAI; however, the relationship was species specific. Maximum ANPP was reached below the maximum
LAI for Q. pagoda and P. occidentalis. P. deltoides ANPP was highest at the maximum LAI, which was achieved with IRR. These results suggest that species-specific cultural practices
producing optimum LAI and maximum ANPP should be identified before fertigation techniques are adopted widely for SRWC production
on agricultural fields. 相似文献
94.
We used a before-after, control-impact design (one year pre-harvest, two years post-harvest) and unlimited-radius point counts to study the effects of typical group-selection harvesting (0.5 gaps ha−1 placed near seed trees within a standard single-tree selection harvest) and intensive group-selection harvesting (4 gaps ha−1 placed on a grid with no harvesting between gaps) on the composition and abundance of breeding birds in tolerant hardwood forests in Algonquin Provincial Park, Ontario. Percent similarity between pre- and post-harvest bird communities was 5–9% lower in selection harvested stands than in reference stands. Differences in percent similarity among the three treatments were not significant, however, suggesting that the changes in the bird community in stands harvested with group selection were not substantially different than those in reference stands. Abundance of aerial foragers and tree-and-shrub nesters increased in response to typical and intensive group selection in the second year post-harvest. By contrast, bark foragers and cavity-nesters decreased in the first year post-harvest and then increased in the second year post-harvest in response to typical group selection. Abundance of 16 (73%) of 22 species was not affected by harvesting. Blue Jay (Cyanocitta cristata), Chestnut-sided Warbler (Dendroica pensylvanica), Least Flycatcher (Empidonax minimus), and White-throated Sparrow (Zonotrichia albicollis) increased in response to intensive group selection in the first or second year post-harvest, whereas Chestnut-sided Warbler, Hairy Woodpecker (Picoides villosus), and White-throated Sparrow increased in response to typical group selection in the first or second year post-harvest. Ovenbird (Seiurus aurocapilla) decreased slightly in response to typical group selection in the second year post-harvest. Our short-term data suggest that intensive, rather than typical, group-selection harvesting is preferred for maintaining densities of cavity-nesting birds and Ovenbird; whether these advantages continue through the remainder of the cutting cycle and beyond requires further investigation. 相似文献
95.
Iazbik MC O'Donnell M Marin L Zaldivar S Hudson D Couto CG 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2010,39(4):433-435
Background: Blood groups in dogs are designated as dog erythrocyte antigen (DEA) 1.1, 1.2, 3, 4, 5, 7, and Dal. There is limited information about the frequency of different antigens in Greyhound dogs, despite their frequent use as blood donors. Objectives: The aims of this study were to determine the frequencies of DEA 1.1, 1.2, 3, 4, 5, and 7 in Greyhounds, to compare the frequencies with those of non‐Greyhound dogs, and to evaluate the presence of naturally occurring anti‐DEA antibodies. Methods: Blood was collected from 206 Greyhound and 66 non‐Greyhound dogs being screened as potential blood donors. Blood‐typing was performed at Animal Blood Resources International by tube agglutination utilizing polyclonal anti‐DEA antibodies. Results: Of the Greyhound dogs, 27/206 (13.1%) were positive for DEA 1.1, and this frequency was significantly lower (P<.0001) than for non‐Greyhound dogs of which 40/66 (60.6%) were DEA 1.1‐positive. The frequency of positivity for both DEA 1.1 and 1.2 was also lower in Greyhounds (P<.0001). There were no significant differences between Greyhounds and non‐Greyhounds for DEA 1.2, 3, 4, 5, or 7. All 137 dogs (113 Greyhounds and 24 non‐Greyhounds) that were evaluated for naturally occurring anti‐DEA antibodies in serum were negative. A higher percentage of Greyhound dogs (57.3%, 118/206) were considered “universal donors” (negative for all DEAs except DEA 4) compared with non‐Greyhound dogs (28%, 13/46). Conclusion: The frequency of positivity for DEA 1.1 in our population of Greyhounds was significantly lower than previously reported for dogs. Furthermore, a large majority of Greyhounds met the criteria for universal donors. 相似文献
96.
Dawn L. Geiser Zachary R. Conley Jamie L. Elliott Jonathan J. Mayo Joy J. Winzerling 《Journal of insect science (Online)》2015,15(1)
Ferritin is a 24-subunit molecule, made up of heavy chain (HC) and light chain (LC) subunits, which stores and controls the release of dietary iron in mammals, plants, and insects. In mosquitoes, dietary iron taken in a bloodmeal is stored inside ferritin. Our previous work has demonstrated the transport of dietary iron to the ovaries via ferritin during oogenesis. We evaluated the localization of ferritin subunits inside CCL-125 [Aedes aegypti Linnaeus (Diptera: Culicidae), yellow fever mosquito] and 4a3b [Anopheles gambiae Giles (Diptera: Culicidae), African malaria mosquito] cells under various iron treatment conditions to further elucidate the regulation of iron metabolism in these important disease vectors and to observe the dynamics of the intracellular ferritin subunits following iron administration. Deconvolution microscopy captured 3D fluorescent images of iron-treated mosquito cells to visualize the ferritin HC and LC homologue subunits (HCH and LCH, respectively) in multiple focal planes. Fluorescent probes were used to illuminate cell organelles (i.e., Golgi apparatus, lysosomes, and nuclei) while secondary probes for specific ferritin subunits demonstrated abundance and co-localization within organelles. These images will help to develop a model for the biochemical regulation of ferritin under conditions of iron exposure, and to advance novel hypotheses for the crucial role of iron in mosquito vectors. 相似文献
97.
Krotscheck U Merton Boothe D Little A Erb H 《Veterinary therapeutics : research in applied veterinary medicine》2010,11(3):E1-E8
Alternatives to intravenous administration of opioids are needed in veterinary medicine. Previous research suggests that opioids can be administered through the buccal mucosa in dogs. This study reports the pharmacokinetics of buprenorphine HCl (0.05 mg/kg) administered transmucosally in six dogs compared with those of buprenorphine HCl (0.015 mg/kg) administered intravenously. The results suggest that the pharmacokinetics of buprenorphine HCl administered intravenously or transmucosally are similar and that transmucosal administration may be considered as a noninvasive alternative to intravenous administration. 相似文献
98.
99.
Georgina?Bond Niall?G?Burnside Daniel?J?Metcalfe Dawn?M?ScottEmail author John?Blamire 《Landscape Ecology》2005,20(5):555-566
To aid effective conservation and management there is a need to understand the effect of landscape on species ecology. The
aim of this research was to assess the effect of landscape parameters on breeding success of barn owls throughout the Rother
and Arun River catchments, Sussex, UK. We used a Geographic Information System to describe the habitat mosaic and landscape
structure within an estimated home range area of 3 km2 around 85 artificial nest box sites. Results showed that land cover was less heterogeneous at successful sites, with home
ranges dominated by a few habitat types of regular patch shapes. Unsuccessful nesting sites had significantly more improved
grassland, suburban land and wetlands than successful sites. Cluster analysis and Principle Components Analysis was used to
assess the similarity of the habitat mosaic within these areas and pellet analysis was undertaken to assess barn owl diet
and prey availability. Ten prey species were recovered from pellets, field vole (Microtus agrestis), common shrews (Sorex araneus) and house mice (Mus musculus) making up nearly 90% of recoveries. However box sites varied in relative proportions of small mammal, and hence prey availability.
Results indicated that land use and landscape structure can affect breeding success in barn owls. Higher levels of poor quality
small mammal habitat were associated with unsuccessful sites. However, at a landscape scale, the habitat mosaic across the
study area lacked variation, limiting analysis and clear correlations between habitat type and positive breeding success,
suggesting that a finer scale was needed in future studies utilising this approach. 相似文献
100.
Krotscheck U Boothe DM Boothe HW 《Veterinary therapeutics : research in applied veterinary medicine》2004,5(3):202-211
Transdermal administration of morphine and fentanyl using a pluronic lecithin organogel was evaluated in dogs. IV administration of morphine and fentanyl resulted in therapeutic serum drug concentrations. Following transdermal administration, however, median serum drug concentrations were never above the limit of quantitation for morphine or fentanyl. These findings indicate that use ofa pluronic lecithin organogel for transdermal administration of morphine or fentanyl cannot be justified. 相似文献