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排序方式: 共有573条查询结果,搜索用时 31 毫秒
1.
Battison AL Buczkowski S Archer FJ 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1996,25(2):43-47
A reference interval for plasma glutamate dehydrogenase (GD) (E.C. 1.4.1.3) activity, of 0-8 IU/L, was established for the cockatiel (Nymphicus hollandicus). An automated modification of a commercial manual assay was used. This enzyme is considered liver specific in humans and numerous domestic animals, due to its organ distribution. A similar distribution was found in cockatiels in this study. Maximal enzyme activity was recovered from liver and kidney homogenate supernatants. Minimal activity was detected in skeletal muscle preparations. These results suggest a potential use for plasma GD activity in the evaluation of hepatocelluar injury/necrosis in cockatiels. 相似文献
2.
Dean Hendrickson Joanna Virgin 《Veterinary Clinics of North America: Equine Practice》2005,21(1):33-44
The rate and outcome of wound healing are determined by many factors,some of which are already in effect when the horse is first presented to the veterinarian. A thorough understanding of wound healing principles,coupled with clear client communication, should enable the practitioner to minimize the number of additional factors that may exacerbate the initial situation. 相似文献
3.
Ecotonal changes and altered tree spatial patterns in lower mixed-conifer forests, Grand Canyon National Park, Arizona, U.S.A. 总被引:1,自引:0,他引:1
This research analyzes patch development and determines tree spatial patterns along the lower mixed-conifer ecotone on the
North Rim of Grand Canyon National Park in Arizona (U.S.A.). Patterns of patch development were interpreted from spatial analyses,
based on tree age and size, and past records of disturbance and climate. Five plots in the ecotone between mixed conifer forests
and monospecific stands of ponderosa pine (Pinus ponderosa) were studied for patterns of patch development. The methods used include: (1) size-structure analyses, to compare species
patch development; (2) dendrochronological dating of tree establishment; (3) tree ring master chronology, to determine periods
of suppressed growth, compared to a Palmer Drought Severity Index; and (4) spatial analyses by species composition, size and
age, with univariate and bivariate analyses of spatial association and spatial autocorrelation. We found an increased density
of shade-tolerant and fire-intolerant species namely clusters of pole-sized white fir, and fewer large ponderosa pine.
This revised version was published online in May 2005 with corrections to the Cover Date.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
4.
de Carvalho Menezes de Almeida Sheylla Foligno Souza-Fabjan Joanna Maria Gonçalves Balaro Mario Felipe Alvarez Bragança Gláucia Mota Pinto Pedro Henrique Nicolau de Almeida José Gabriel Moura Ana Beatriz Bossois da Fonseca Jeferson Ferreira Brandão Felipe Zandonadi 《Tropical animal health and production》2018,50(2):427-432
Tropical Animal Health and Production - This study evaluated the effect of two doses of prostaglandin at different intervals on reproductive parameters of crossbred ewes. In Experiment 1, 30 ewes... 相似文献
5.
6.
Gemma A. Miller Robert M. Rees Bryan S. Griffiths Joanna M. Cloy 《Soil Use and Management》2020,36(2):285-298
Agricultural soils are important sources of greenhouse gases (GHGs). Soil properties and environmental factors have complex interactions which influence the dynamics of these GHG fluxes. Four arable and five grassland soils which represent the range of soil textures and climatic conditions of the main agricultural areas in the UK were incubated at two different moisture contents (50 or 80% water holding capacity) and with or without inorganic fertiliser application (70 kg N ha−1 ammonium nitrate) over 22 days. Emissions of N2O, CO2 and CH4 were measured twice per week by headspace gas sampling, and cumulative fluxes were calculated. Multiple regression modelling was carried out to determine which factors (soil mineral N, organic carbon and total nitrogen contents, C:N ratios, clay contents and pH) that best explained the variation in GHG fluxes. Clay, mineral N and soil C contents were found to be the most important explanatory variables controlling GHG fluxes in this study. However, none of the measured variables explained a significant amount of variation in CO2 fluxes from the arable soils. The results were generally consistent with previously published work. However, N2O emissions from the two Scottish soils were substantially more sensitive to inorganic N fertiliser application at 80% water holding capacity than the other soils, with the N2O emissions being up to 107 times higher than the other studied soils. 相似文献
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8.
Niora J. Fabian Michael Y. Esmail Lauren Richey Sureshkumar Muthupalani Jennifer L. Haupt Joanna Joy Sebastian E. Carrasco 《Journal of veterinary diagnostic investigation》2021,33(3):582
Cutaneous leiomyosarcomas are malignant mesenchymal tumors of smooth muscle origin and are reported occasionally in avian species. A 14-y-old male laboratory White Carneau pigeon (Columba livia) was presented for surgical excision of a cervical soft tissue mass. Ultrasonography with color flow Doppler imaging revealed multiple cavitations of mixed echogenicity within the mass and vascularization. Histologically, the dermis and subcutis were expanded by a densely cellular multinodular mass comprised of fusiform cells forming haphazardly arranged broad streams and short interwoven bundles, often surrounding blood vessels and variably sized cavitations. Neoplastic cells were strongly immunopositive for desmin and α–smooth muscle actin, and negative for pancytokeratin, S100, and von Willebrand factor. Based on histopathology and IHC findings, the cutaneous mass was diagnosed as leiomyosarcoma (LMS). The pigeon died 312 d post-operatively. Postmortem examination revealed masses infiltrating the left and right pulmonary airways and one hepatic nodule, but no regrowth at the surgical site. Histologic and IHC evaluation of the pulmonary and hepatic masses were consistent with LMS, representing metastatic foci from the primary cutaneous LMS. Our case highlights the malignant behavior and histomorphologic features of cutaneous LMS in an avian species. 相似文献
9.
Jerzy Juśkiewicz Bartosz Fotschki Joanna Jaworska Marta Siemieniuch 《Animal Science Journal》2021,92(1):e13603
Gastrointestinal microbiota play a key role in the nutrients digestion and hence maintaining animal health and welfare. The diet offered to the animals in captivity may differ considerably from that on natural pastures. In a stabled maintenance system, horses have a limited choice of habitat and feed. Time spend for feeding is relevant for equine welfare because the reduction of the time devoted for foraging may be responsible for inducing gastric inflammation and ulceration. Therefore, in the present study, it was hypothesized that fecal bacterial fermentative processes differ between free-roaming and stabled Konik Polski Horses (KPHs) with respect to microbial enzymatic activity, and thus the fecal concentration of short-chain fatty acids (SCFA), which can be further utilized for assessing the feeding behavior and welfare in free-roaming versus stabled horses. The SCFA concentration and profile, as well as the extracellular and intracellular activities of selected bacterial enzymes, were characterized in horse feces collected during the winter and summer feeding seasons. The results showed higher enzymatic activity and SCFA production in the feces excreted by free-roaming versus stabled horses, especially during summer. An increase in pasture plant diversity may be beneficial for the gastrointestinal microbiota and hence for maintaining health and welfare. 相似文献
10.
Georgia Ane Raquel Sehn Amanda de Cssia Nogueira Eveline Lopes Almeida Yoon Kil Chang Caroline Joy Steel 《Cereal Chemistry》2015,92(4):405-410
This study evaluated the influence of calcium and magnesium ions on the empirical rheological properties of wheat flour to verify possible effects of these ions on processing because, in addition to their nutritional importance, they are also responsible for water hardness. Calcium (0–1.30 g/100 g) and magnesium (0–0.34 g/100 g) ions from sulfate salts were added to wheat flour, according to a central composite rotatable design. The farinograph and extensigraph properties of wheat flour and its mixtures were evaluated. The results were analyzed by response surface methodology. Calcium ions stood out for increasing water absorption, decreasing mixing stability, and producing a delayed effect on dough extensibility (reduced at 135 min). Magnesium ions influenced most flour rheological properties in a similar manner to oxidizing agents (increased dough stability, increased resistance to extension, and reduced extensibility), thus proving to be a possible replacement agent for these additives. An interaction effect of the combined calcium and magnesium ions was observed on dough development time. The results showed that effects on processing can occur when wheat flour fortification is made, and adaptations on wheat flour specifications, product formulation, and processing parameters may be required. 相似文献