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41.
A 10‐year‐old German Warmblood gelding was referred to the Equine Department of the Vetsuisse Faculty, University of Zurich, Switzerland, for an iris mass OD, lethargy, intermittent fever, and coughing. Ophthalmic examination revealed a 7 × 9 mm raised, fleshy, whitish to pinkish, vascularized iris mass at the 2 o`clock position OD. Fundic examination showed multifocal round, brown to black, slightly raised lesions with indistinct margins and a surrounding hyperreflective zone OU. Physical examination revealed a temperature of 39.2 °C, sinus tachycardia, preputial and ventral edema, and an enlarged right mandibular lymph node. Results of a complete blood count and plasma biochemical profile showed mild anemia, leukocytosis, and thrombocytopenia. Severe splenopathy, moderate splenomegaly, and severe pulmonary pathology with nodules and large areas of consolidated lung parenchyma were observed on abdominal ultrasound and thoracic radiographs, respectively. Fine needle aspirates of the enlarged mandibular lymph node showed malignant epithelial neoplastic cells. The horse was euthanized because of the poor prognosis and subsequently underwent postmortem examination. Macroscopic necropsy and histopathology revealed an adenocarcinoma of suspected pulmonary origin with involvement of eyes, heart, liver, kidneys, spleen, diaphragm, skeletal muscles, mandibular, pulmonary, and internal iliac lymph nodes. Metastatic adenocarcinoma should be considered as a differential diagnosis in horses with iris masses, multifocal chorioretinal infiltrates, and clinical signs that conform to a paraneoplastic syndrome.  相似文献   
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Vascular wilt caused by the soil-borne fungus Verticillium dahliae is a major yield and quality-limiting disease across a broad spectrum of crop plants worldwide. Sulphur-enhanced plant defence mechanisms provide an opportunity to effectively and environmentally safely constrain the wilt disease levels in planta. To evaluate the influence of sulphur nutrition on the protective potential of these mechanisms, two near-isogenic tomato genotypes differing in fungal susceptibility, were treated with low or supra-optimal sulphur supply. Microscopic analysis revealed a significant sulphur-induced decrease in the amount of infected vascular cells in both genotypes. However, plant shoot and severely pathogen-affected root growth did not display this distinct alleviating influence of sulphur nutrition. Rates of leaf photosynthesis were impeded by Verticillium dahliae infection in both genotypes especially under low sulphur nutrition. However, assimilate transport rates in the phloem sap were enhanced by fungal infection more in the resistant genotype and under high sulphur nutrition suggesting a stronger sink for assimilates in infected plant tissues possibly involved in sugar-induced defence. A SYBR Green-based absolute quantitative Real-Time assay using a species-specific primer was developed which sensitively reflected sulphur nutrition-dependent changes in fungal colonization patterns. High sulphur nutrition significantly reduced fungal spread in the stem in both tomato genotypes. Concentrations of selected sulphur-containing metabolites revealed an increase of the major anti-oxidative redox buffer glutathione under high sulphur nutrition in response to fungal colonization. Our study demonstrates the existence of sulphur nutrition-enhanced resistance of tomato against Verticillium dahliae mediated by sulphur-containing defence compounds.  相似文献   
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Some species of the genusOrobanche are among the most devastating parasitic weeds, causing extensive damage in agricultural fields. Considering the difficult control due to seed longevity in the soil, small seed size, high fecundity and a subterranean phase that allows them to parasitize the host before they emerge and become evident, the development of diagnostic markers is highly recommended. In our study we identified potential molecular diagnostic markers from the plastid genome in order to distinguish among the most importantOrobanche species attacking crops in Andalusia, the southern region of the Iberian Peninsula. The study has consideredO. crenata, O ramosa andO. cumana causing serious losses in legumes, solanaceous crops and sunflower fields, respectively, andO. minor that, although abundant in Andalusia, has to our knowledge not yet been found parasitizing agricultural hosts. We amplified a non-coding region from the plastid genome, studied sequence differences among the amplified fragments and digested those of the same length with selected restriction enzymes. Here, we propose a molecular protocol to distinguish the main parasitic plants in crop fields of southern Spain. Different applications such as identification ofOrobanche seeds in soil or crop seed lots are discussed in order to offer right crop recommendations or to prevent new infestation of parasite-free fields. Recommendations for further development of these diagnostic markers are also considered. http://www.phytoparasitica.org posting Jan. 15, 2007.  相似文献   
44.
Priming: it’s all the world to induced disease resistance   总被引:2,自引:0,他引:2  
After infection by a necrotising pathogen, colonisation of the roots with certain beneficial microbes, or after treatment with various chemicals, many plants establish a unique physiological situation that is called the ‘primed’ state of the plant. In the primed condition, plants are able to ‘recall’ the previous infection, root colonisation or chemical treatment. As a consequence, primed plants respond more rapidly and/or effectively when re-exposed to biotic or abiotic stress, a feature that is frequently associated with enhanced disease resistance. Though priming has been known as a component of induced resistance for a long time, most progress in the understanding of the phenomenon has been made over the past few years. Here we summarize the current knowledge of priming and its relevance for plant protection in the field.  相似文献   
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A total of 44 live cheetahs were examined sonographically between 1989 and 1994. Seventeen of these animals originated from 4 European facilities, the other 27 cheetahs were examined in 3 facilities in Namibia. Evaluation of the cheetahs included a clinical examination, abdominal ultrasound, and complete blood work. Splenic myelolipomas were diagnosed sonographically in 11 cheetahs. In 7 cheetahs the diagnosis was confirmed at necropsy. Nine of the 14 cheetahs in Europe had myelolipomas in the spleen, while in the African cheetahs there were only 2 animals with myelolipomas. Histologically these lesions were characterized by fatty nodules. A more fitting term of Nodular Lipomatosis of the spleen is therefore suggested. All cheetahs with nodular lipomatosis of the spleen, had concurrent chronic diseases at necropsy. An indicator function of splenic nodular lipomatosis for chronic disease and/or stress is possible.  相似文献   
47.
The horticultural sector has seen much structural change both nationally and internationally over the last decades, but the implications for plant health have been neglected. We review in the context of the risk of emerging plant diseases recent developments including the movement towards a global horticultural market, the rise of the horticultural industry of many developing countries, and the economic integration of the European Union. North America is typically well ahead of other regions in economic developments, and in horticulture this is shown for example by the growing importance of Mexican growers. Asia is rapidly catching up also in horticulture, with China and India becoming key producers. Australia and New Zealand show the impact of change in horticulture extension services. The Eastern enlargement of the EU is having profound influences on fruit and vegetable growers both in the new and in the old member countries. Similar developments are taking place in South America and Africa. In all continents, there is a general trend towards fewer and larger horticultural growers, an increasing role of supermarkets and a concentration of the retail pathways. These developments have consequences for the control of plant pathogens and invasive species. Technical issues seem to be of lesser consequence in terms of structural change compared with labour and trade aspects. However, examples can be found where technical innovations have opened up new opportunities or provided solutions to pressing problems, as can be seen in the hardy nursery stock and ornamental industry in the UK. Future technical, economic and social impacts on the sector are likely to play a key role for securing a diverse and reliable food supply for the still expanding world's population. Recent advances in modelling disease spread in complex networks representing trade pathways should be used to target control of introductions of new plant pathogens. There is a need for more long-term research on how structural change in the horticultural sector will affect and be affected by climate change.  相似文献   
48.
ABSTRACT: Understanding protein and gene function requires identifying interaction partners usingbiochemical, molecular or genetic tools. In plants, searching for novel protein-proteininteractions is limited to protein purification assays, heterologous in vivo systems such as the yeast-two-hybrid or mutant screens. Ideally one would be able to search for novel proteinpartners in living plant cells. We demonstrate that it is possible to screen for novel proteinproteininteractions from a random library in protoplasted Arabidopsis plant cells and recoversome of the interacting partners. Our screen is based on capturing the bi-molecularcomplementation of mYFP between an YN-bait fusion partner and a completely random preyYC-cDNA library with FACS. The candidate interactions were confirmed using in plantaBiFC assays and in planta FRET-FLIM assays. From this work, we show that the wellcharacterized protein Calcium Dependent Protein Kinase 3 (CPK3) interacts with APX3,HMGB5, ORP2A and a ricin B-related lectin domain containing protein At2g39050. This isone of the first random in planta screens to be successfully employed.  相似文献   
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