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排序方式: 共有125条查询结果,搜索用时 46 毫秒
1.
Latimer KS Bounous DI Colatos C Carmichael KP Howerth EW 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1996,25(1):23-26
Extreme eosinophilia with disseminated eosinophilic granulomatous disease is described in a 4-year-old Arabian mare. Clinical signs included weight loss, coughing, jugular distention, and ventral edema. Cutaneous lesions were not observed. Eosinophilic inflammation was observed in cytologic specimens from the respiratory tract, body cavities, and lymph nodes. At necropsy, a 20-cm diameter intrathoracic mass was observed. Smaller nodules were present in the lymph nodes, liver, spleen, adrenal glands, pancreas, and skeletal muscle. Histologically, these masses and nodules were characterized by infiltrates of eosinophils, macrophages, and multinucleated giant cells, reactive fibroplasia; and multifocal eosinophilic coagula. Microscopically, mild eosinophilic infiltrates were observed in sections of stomach, small intestine, colon, and pleura; however, gross lesions were not observed in these tissues at necropsy. The etiology of the extreme eosinophilia and disseminated eosinophilic granulomatous disease in this horse was not determined. 相似文献
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Paige E Boyle Michael D Richardson Mary C Savin Douglas E Karcher Daniel A Potter 《Pest management science》2019,75(8):2071-2078
Earthworm activity is beneficial in most natural and agricultural systems, but excessive earthworm casting is a problem on sports fields worldwide. Expulsion of soil‐rich earthworm fecal matter, or casts, as mounds of soil on the turf canopy can muddy the surface, reduce photosynthesis, and lead to thinning, weed invasion and surface softening. Casts affect ball roll on sports fields, cause fouling of maintenance equipment, and dull mower blades. Build‐up of cast material on reel mower units can affect height and quality of cut. Casting activity is dependent on environmental conditions such as soil texture, temperature, moisture, pH, and organic matter. Response to environmental conditions varies by species. Management options are limited, because no pesticides are specifically labeled for earthworm control at this time, and cultural control methods such as soil modification, turfgrass clipping removal, and sand topdressing have limited and inconsistent efficacy. Products containing plant‐derived saponins and irritants show promise for earthworm management. Pest management practices to mitigate excessive earthworm casting will likely need to be species‐specific, but limited knowledge of earthworm identification by end‐users further inhibits the efficacy of control measures. © 2019 Society of Chemical Industry 相似文献
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Freshly cleaved mica sheets with aluminium- or iron(III)-hydroxy species on the cationexchange surface were prepared by suitable treatment with AlCl3 or FeCl3. These surfaces were considered as model soilk mineral surfaces and their interaction with phosphate studied using techniques previously developed for the study of single planar surfaces.Adsorption isotherms for both the iron(III) and aluminium systems were very similar and could be interpreted as two Freundlich isotherms indicating two different adsorption processes, one operating below a solution concentration of 10?5 M and thee other above. Results obtained from the continuous monitoring of adsorption indicate that a rearrangement of adsorbed phosphate occurs with time on both the aluminium- and iron(III)hydroxy surfaces. This rearrangement reduces the rate of desorption and could be a cause of phosphate fixation in soils. 相似文献
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Paige E. Axelrood Melody Neumann David Trotter Reed Radley Gwen Shrimpton John Dennis 《New Forests》1995,9(1):35-51
Twelve Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlots from coastal British Columbia were assayed for seedborne Fusarium. All of the seedlots were contaminated with Fusarium. Percent of nonstratified seeds from individual seedlots harboring Fusarium ranged from 0.3% to 95.4%. Sixty-seven percent of the seedlots had Fusarium on less than 2% of the seeds. Post-stratification seedborne Fusarium levels were significantly less for running water imbibition compared to standing water imbibition. However, seedling growth at a container nursery was not consistently different for stratified seed imbibed initially in standing or running water. Fusarium disease symptoms were not observed in the nursery environment. The species of Fusarium isolated from seed were F. acuminatum, F. avenaceum, F. lateritium, F. moniliforme, F. oxysporum, F. poae and F. sambucinum. Twelve Fusarium isolates, comprising six species, were assessed for pathogenicity. Disease symptoms were observed after four weeks incubation and Fusarium isolates ranged in virulence from low to high. Fusarium oxysporum isolates were the most pathogenic. 相似文献
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The potential for traditional and local ecological knowledge to contribute to biodiversity conservation has been widely recognized, but the actual application of this knowledge to biodiversity conservation is not easy. This paper synthesizes literature about traditional and local ecological knowledge and forest management in the Pacific Northwest to evaluate what is needed to accomplish this goal. We address three topics: (1) views and values people have relating to biodiversity; (2) the resource use and management practices of local forest users, and their effects on biodiversity; (3) models for integrating traditional and local ecological knowledge into biodiversity conservation on public and private lands. We focus on the ecological knowledge of forest users belonging to three groups who inhabit the region: American Indians, family forest owners, and commercial nontimber forest product harvesters. 相似文献
9.
Chris Langdon Ford Evans Dave Jacobson Michael Blouin 《Aquaculture (Amsterdam, Netherlands)》2003,220(1-4):227-244
Parental families (G0) in three lines of Pacific oysters were selected based on live weight and meat yields at harvest. The average live weight yield of progeny (G1) from crossing G0-selected lines in seven trials was 9.5% greater than that of nonselected control families and live weight yields were significantly greater (ANOVA, P<0.001) in four out of seven trials. The response to selection was greater if G1 families were tested at the same site as their parents' selection site rather than at a different site, although this effect was only significant for G1 families of cohort 5 (P<0.01) but not cohort 7 (P>0.05). A significant genotype×environment interaction affected yields in both cohort 5 and cohort 7 (ANOVA; P<0.001). In addition, correlation between the yields of the same families planted at both intertidal and subtidal sites was positive but weak (cohort 5, r=0.30; cohort 7, r=0.35), indicating that selection for high yield in one environment would likely result in a low correlated response in a different environment. Nonetheless, it was possible to identify six families in cohort 5 and four families in cohort 7 that were among the top 10 families at both sites. Further evaluation of families across a wider range of environments is needed to determine if it is possible to substantially improve yields by selecting “generalist” families that perform well along the whole Pacific coast, or whether it will be necessary to select lines that are suited to particular sites. 相似文献
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