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81.
Elisa Spoldi Tobias Schwarz Silvia Sabattini Massimo Vignoli Simona Cancedda Federica Rossi 《Veterinary radiology & ultrasound》2017,58(1):29-37
A better understanding of the CT features of different forms of canine and feline adipose tumors would be valuable for improving patient management and treatment. The purpose of this retrospective, cross‐sectional study was to describe and compare the CT features of pathologically confirmed lipomas, infiltrative lipomas, and liposarcomas in a sample of canine and feline patients. A total of 50 animals (46 dogs, four cats) and a total of 60 lesions (23 lipomas, 20 infiltrative lipomas, and 17 liposarcomas) were included in the study. Lipomas appeared as round to oval‐shaped (n = 21), well‐marginated (n = 20) fat‐attenuating lesions. Infiltrative lipomas appeared as homogeneous, fat‐attenuating masses but, unlike lipomas, they were most commonly characterized by an irregular shape (75%; P < 0.001), and linear components, hyperattenuating relative to the surrounding fat (100%; P < 0.05). Liposarcomas were represented exclusively by heterogeneous lesions with soft tissue attenuating components with a multinodular appearance (76.5%; P < 0.05). Regional lymphadenopathy (n = 10) and amorphous mineralization (n = 4) were also observed in association with liposarcomas. Computed tomography can provide useful information regarding disease location, extent, and involvement of the adjacent structures. Tumor definition and shape were the most useful parameters to differentiate between lipomas and infiltrative lipomas. The presence of a heterogeneous mass, with a multinodular soft tissue component and associated regional lymphadenopathy and mineralization, were features favoring a diagnosis of liposarcoma. 相似文献
82.
The EFSA quantitative approach to pest risk assessment – methodological aspects and case studies 下载免费PDF全文
G. Gilioli G. Schrader J.‐C. Grégoire A. MacLeod O. Mosbach‐Schulz T. Rafoss V. Rossi G. Urek W. van der Werf 《EPPO Bulletin》2017,47(2):213-219
A new method for pest risk assessment and the identification and evaluation of risk‐reducing options is currently under development by the European Food Safety Authority (EFSA) Plant Health Panel. The draft method has been tested on pests of concern to the European Union (EU). The method is adaptable and can focus either on all the steps and sub‐steps of the assessment process or on specific parts if necessary. It is based on assessing changes in pest population abundance as the major driver of the impact on cultivated plants and on the environment. Like other pest risk assessment systems the method asks questions about the likelihood and magnitude of factors that contribute to risk. Responses can be based on data or expert judgment. Crucially, the approach is quantitative, and it captures uncertainty through the provision by risk assessors of quantile estimates of the probability distributions for the assessed variables and parameters. The assessment is based on comparisons between different scenarios, and the method integrates risk‐reducing options where they apply to a scenario, for example current regulation against a scenario where risk‐reducing options are not applied. A strategy has been developed to communicate the results of the risk assessment in a clear, comparable and transparent way, with the aim of providing the requestor of the risk assessment with a useful answer to the question(s) posed to the EFSA Plant Health Panel. The method has been applied to four case studies, two fungi, Ceratocystis platani and Cryphonectria parasitica, the nematode Ditylenchus destructor and the Grapevine flavescence dorée phytoplasma. Selected results from these case studies illustrate the types of output that the method can deliver. 相似文献
83.
Eve Runno-Paurson Triinu Remmel Ann Ojarand Alice Aav Marika Mänd 《European journal of plant pathology / European Foundation for Plant Pathology》2010,128(3):373-383
The characteristics of populations of Phytophthora infestans from organic farms, small conventional farms and large conventional farms were determined from isolates collected in northern
Estonia in 2004 and 2005. For the population as a whole 41% were A2; all virulence factors to the 11 R genes from Solanum demissum were found; and more than 70% had high or intermediate resistance to metalaxyl. Isolates from organic farms tended to have
more complex pathotypes than isolates from either large or small conventional farms, but there was a higher proportion of
metalaxyl resistant isolates from large conventional farms than from small conventional farms or from organic farms. 相似文献
84.
Isidre Llorente Albert Vilardell Pere Vilardell Elisabetta Pattori Riccardo Bugiani Vittorio Rossi Emilio Montesinos 《European journal of plant pathology / European Foundation for Plant Pathology》2010,128(1):127-141
Stemphylium vesicarium, the causal agent of brown spot of pear, overwinters in the leaf residues of pear and herbaceous plants of the orchard floor.
Pseudothecia of the teleomorph, Pleospora allii, are formed on these residues where they produce ascospores. New methods were tested aimed at reducing this overwintering
inoculum and increasing the efficacy of control of brown spot of pear. Sanitation methods were evaluated in nine trials in
Girona (Spain) and Ferrara (Italy) over a 4-year period. The sanitation methods were leaf litter removal in December to February,
and application of biological control agents (commercial formulates of Trichoderma spp.) to the orchard ground cover from February to May. Fungicides were also applied to the trees during the pear-growing
season, scheduled according to the BSPcast model. The different methods were tested as stand-alone applications or in combination.
All methods consistently reduced the disease incidence at harvest on fruit with an efficacy between 30 to 60% for leaf litter
removal and more than 60% for the combination of leaf litter removal and biological control. Efficacy of sanitation alone
(leaf litter removal and biological control) in reducing the brown spot level on fruit was similar in most of the trials to
the efficacy obtained when fungicides were applied alone. However, integration of sanitation methods and fungicides did not
improve the efficacy of disease control over the level provided by fungicides alone. 相似文献
85.
CASE SUMMARY: A 5-year-old male neutered indoor cat presented for evaluation and treatment of an acute onset of nasal discharge and open-mouth breathing of 3 days' duration. He had been treated for asthma prior to presentation, but his clinical signs were more consistent with upper airway disease. Thoracic radiographs were suggestive of asthma. However, a soft tissue mass was noted in the nasopharynx on a lateral cervical radiograph. Nasopharyngeal examination revealed the mass to be a trichobezoar (hair ball) lodged in the nasopharynx, removal of which led to resolution of clinical signs. The cat re-presented with a second nasopharyngeal trichobezoar approximately 1 year later, which was also successfully removed. CLINICAL SIGNIFICANCE: Nasopharyngeal disease has myriad potential infectious, inflammatory and neoplastic etiologies. However, simpler causes such as foreign bodies can be considered in cases of acute-onset nasopharyngeal disease. To the authors' knowledge, this is the first reported case of a nasopharyngeal trichobezoar foreign body in a cat. 相似文献
86.
87.
88.
Tito Caffi Sara Elisabetta Legler Riccardo Bugiani Vittorio Rossi 《European journal of plant pathology / European Foundation for Plant Pathology》2013,135(4):817-829
Chasmothecia of Erysiphe necator form in one season, survive winter and discharge ascospores that cause primary infections and trigger powdery mildew epidemics in the next season. A strategy for powdery mildew control was developed based on (i) the reduction in overwintering chasmothecia and on (ii) spring fungicide applications to control ascosporic infections timed based on estimate risk (two to five sprays per season). Several fungicides, the hyperparasite Ampelomyces quisqualis, and a mineral oil product were first tested as separate applications in a greenhouse and in vineyards. In the greenhouse, A. quisqualis suppressed chasmothecia formation by 41 %; fungicides and mineral oil suppressed chasmothecia formation by 63 % and ascospore viability by 71 %. In vineyards, application of boscalid + kresoxim-methyl or meptyldinocap once after harvest, as well as application of A. quisqualis pre- and post-harvest, delayed disease onset and epidemic development in the following season by 1 to 3 weeks and lowered disease severity (up to the pea-sized berry stage) by 56 to 63 %. Risk-based applications of sulphur and of synthetic fungicides provided the same control as the grower spray program but required fewer applications (average reduction of 47 %). Sanitation strategies were then tested by combining products and application times (late-season, and/or pre-bud break, and/or spring). Adequate disease control with a reduced number of sprays was achieved with the following combination: two applications of A. quisqualis (pre- and post-harvest), one application of mineral oil before bud break, and model-based applications of sulphur fungicides between bud break and fruit set. 相似文献
89.
90.
Federico Rossi Ruth M. Potrafka Ferran Garcia Pichel Roberto De Philippis 《Soil biology & biochemistry》2012
Biological soil crusts (BSCs) are highly specialized topsoil microbial communities commonly found in arid and semiarid environments, permeated by a polymeric matrix of polysaccharides. BSCs can in principle influence edaphic properties such as texture, pore formation and water retention, which in turn determine water distribution and biological activity in dry lands. This paper investigates the influence of biotic and abiotic factors on BSC hydraulic conductivity, a parameter gauging the ease with which water can move through the pore spaces. Texture, phototroph abundance, microbial composition, and extracellular carbohydrate content were considered as potentially relevant parameters in a correlational study of BSC samples that spanned 1.5 orders of magnitude in hydraulic conductivity. A newly developed, non-destructive extraction method enabled us to directly quantify the specific role of extracellular polysaccharides on soil permeability on a variety of samples. Hydraulic conductivity showed a strongest correlation with texture (positive with sand content, negative with silt and clay). A weaker negative correlation with carbohydrate content, especially with polysaccharides having a molecular weight < 100 kDa, was also detected. In multiple regression analyses texture (silt content) was sufficient to explain most of the variation in hydraulic conductivity However, experimental removal of polymeric carbohydrates, resulted invariably in a substantial decrease in hydraulic conductivity for any given sample (between 1.7 and 3.3 fold). Our results suggest that while soil texture determines overall hydraulic conductivity in BSCs, the presence of exopolysaccharides can significantly enhance it, likely by conferring a spongy structure to a BSC thus increasing the number of waterways within it. 相似文献