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A 22-month-old indoor/outdoor neutered male domestic short-haired cat had a history of progressive lethargy, vomiting, and decreased appetite. Abdominal ultrasound revealed an irregular hyperechoic mass in the mid-abdomen. He was unresponsive to symptomatic medical management and was euthanized after 3 days of hospitalization. A diagnosis of disseminated extraintestinal toxoplasmosis was made based on the finding of intracytoplasmic protozoan parasites on histopathological examination of mesenteric lymph nodes, hepatic and intestinal samples, and on immunohistochemistry.  相似文献   
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It is likely that in the near future sequence information from sequencing programmes and EST libraries will generate an abundance of genic microsatellite markers. This study is focused on the assessment of their likely impact and performance vis-à-vis their genomic counterparts. Microsatellites from two sources were used to assess the genetic diversity in 56 old and new varieties of bread wheat on the UK Recommended List. A set of 12 microsatellite markers generated from genomic libraries and 20 expressed sequence tag (EST)-derived microsatellites were used in the study, and the performance of both marker sets assessed. The EST-derived or genic microsatellites delivered fingerprints of superior quality, amplifying clear products with few stutter bands. Diversity levels as revealed bygenic microsatellites are similar to the few published results. The PIC values for the genic markers were generally lower than those calculated for the genomic microsatellites, though advantages of both marker classes for variety identification applications are discussed. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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ABSTRACT The impact of Brassica napus seed meal on the microbial complex that incites apple replant disease was evaluated in greenhouse trials. Regardless of glucosinolate content, seed meal amendment at a rate of 0.1% (vol/vol) significantly enhanced growth of apple and suppressed apple root infection by Rhizoctonia spp. and Pratylenchus penetrans. High glucosinolate B. napus cv. Dwarf Essex seed meal amendments did not consistently suppress soil populations of Pythium spp. or apple root infection by this pathogen. Application of a low glucosinolate containing B. napus seed meal at a rate of 1.0% (vol/vol) resulted in a significant increase in recovery of Pythium spp. from apple roots, and a corresponding reduction in apple seedling root biomass. When applied at lower rates, B. napus seed meal amendments enhanced populations of fluorescent Pseudomonas spp., but these bacteria were not recovered from soils amended with seed meal at a rate of 2% (vol/vol). Seed meal amendments resulted in increased soil populations of total bacteria and actinomycetes. B. napus cv. Dwarf Essex seed meal amendments were phytotoxic to apple when applied at a rate of 2% (vol/vol), and phytotoxicity was not diminished when planting was delayed for as long as 12 weeks after application. These findings suggest that B. napus seed meal amendments can be a useful tool in the management of apple replant disease and, in the case of Rhizoctonia spp., that disease control operates through mechanisms other than production of glucosinolate hydrolysis products.  相似文献   
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Mazzola M 《Phytopathology》1998,88(9):930-938
ABSTRACT Systematic studies were conducted to elucidate the role of different soil microbial groups in the development of apple replant disease. Populations of targeted microorganisms were reduced by the application of semiselective biocides and soil pasteurization. Bacteria were not implicated in the disease, because application of the antibiotic chloramphenicol reduced soil populations of bacteria but failed to improve growth of apple transplants, while enhanced growth was achieved at pasteurization temperatures that did not alter attributes of the bacterial community recovered from apple roots. Populations of Pratylenchus penetrans were below the damage threshold level in eight of nine orchards surveyed, and nematicide applications failed to enhance apple growth in four of five replant soils tested, indicating that plant parasitic nematodes have a minor role or no role in disease development. Application of the fungicide difenconazole or metalaxyl enhanced growth of apple in all five replant soils, as did fludioxinil in the two soils tested. Soil pasteurization enhanced growth of apple and resulted in specific changes in the composition of the fungal community isolated from the roots of apple seedlings grown in these treated soils. Cylindrocarpon destructans, Phytophthora cactorum, Pythium spp., and Rhizoctonia solani were consistently isolated from symptomatic trees in the field and were pathogenic to apple. However, the composition of the Pythium and Rhizoctonia component and the relative contribution of any one component of this fungal complex to disease development varied among the study orchards. These findings clearly demonstrate that fungi are the dominant causal agents of apple replant disease in Washington state.  相似文献   
6.
Sprouting can be an important mechanism of regeneration in harvested cypress (Taxodium sp.) wetlands; however, limited information exists on factors influencing sprouting. We examined the influence of harvesting practices, tree size, and site conditions on stump sprouting in eight pondcypress (Taxodium distichum var. nutans (Ait.) Sweet) wetlands in Florida, USA. Stumps were cut at three heights: 20 cm below high water level, at high water, and 40 cm above high water. Half of each site was harvested using a sawhead feller and the other half using shearhead. We monitored sprouting for 2 years post-harvest. Stump height affected first year sprouting, but the effect disappeared during year 2. Felling equipment did not affect sprouting; however, the shearhead caused greater stump damage. Sprouting declined with increasing parent tree size; percentage of stumps with sprouts after 2 years was 68% for trees 10–14 cm dbh and 28% for trees 20–24 cm dbh. Stump sprouting ranged among sites from 23 to 54% after 2 years. Results indicate that sprouting may be an important, but inadequate, form of regeneration. At sites with short hydroperiods, dense understories, and/or predominance of trees greater than 20 cm dbh, reduced sprouting may occur, and planting seedlings may be beneficial.  相似文献   
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We studied the impact of organic loads due to the biodeposition of a fish farm in a non-impacted coastal area of the Tyrrhenian Sea (Western Mediterranean). Sediment chemistry and benthic microbial community were investigated from July 1997 to February 1998 on monthly basis at two stations: one was located under the fish farm, while the second was about 1 km away, and served as a reference site. The presence of the cage induced rapid changes in the benthic conditions: the sediments were rapidly (after 6 weeks) reduced. A significant accumulation of biopolymeric carbon was observed beneath the cage both 2 weeks after the initial cage deployment, on non-impacted sediments, and 5–7 months after, and appeared to be related to the fish farm production cycle. The density of microbial communities beneath the fish farm increased only during the first month of farming activity (July) and partially 7 months after cage disposal (i.e. in January), when there was a significant sediment organic enrichment. Additional evidence of rapid impact of the fish farm on the benthic bacterial communities is provided by the increase in the numbers of autofluorescent microbial cells. The photosynthetic eukaryotic cells displayed a highly reduced contribution to total autofluorescent microbial density, indicating that their decrease is related with biopolymeric carbon accumulation, and probably was due also to “shadow effect” induced by suspended material, coming from the fish farm, on the environment below. We propose here, to apply the ratio of culturable heterotrophic bacteria to microbial direct counts (CFU/MDC) to detect fish farm impact. In cage sediments, organic enrichment and the consequent modification of the characteristics of the benthic environment, determined an increase in aerobic heterotrophic bacteria and vibrio density indicating that they are efficient colonizers of organic-rich sediments. Densities of Escherichia coli and Enterococci were not significantly higher than in the reference site, and are likely of terrestrial origin. Thus they cannot be used as specific indicators of fish farm impact.  相似文献   
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Veterinary Research Communications - Mazzola, S., Albertini, M., Pastore, C., Pirrone, F. and Clement, M.G., 2007. Carbon monoxide induced prevention of vascular ristenosis is not related to nitric...  相似文献   
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