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101.
Background — Fine needle aspiration cytology is being used for the diagnosis of various neoplasms, but we are unaware of reports dealing with the cytologic features of canine pilomatricoma.
Objective — The purpose of this report was to describe the cytologic features of pilomatricoma in 3 dogs.
Methods — Fine-needle aspirates were obtained from cutaneous masses using a 25-ga needle. Smears were prepared and stained with May-Grünwald-Giemsa and hematoxylin and eosin. The cutaneous masses were excised and routinely processed for histologic examination.
Results — Cytologic features of all 3 tumors included high cellularity and numerous clusters of tightly arranged of basaloid cells with evenly distributed chromatin and small distinct nucleoli surrounding sheets of "ghost cells". Ghost cells were characterized by a central unstained zone corresponding to the site previously occupied by the nucleus. Amorphous keratinized material was observed in 1 tumor. Histopathologic findings confirmed the diagnosis of pilomatricoma in all 3 cases.
Conclusions — Basaloid cells in association with ghost cells are important cytopathologic criteria that may provide a definitive cytologic diagnosis of pilomatricoma in dogs, and may help avoid a false diagnosis of malignancy.  相似文献   
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Veterinary Research Communications - Research data on milk composition in cetaceans are scattered and fragmentary. This paper analyses the gross and mineral composition, the fatty acids profile and...  相似文献   
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The possibility of using the Iosipescu shear test device to study the combined shear and compression behavior of anisotropic materials was examined. Measurements were made using both an original (Wyoming version) and an in-house modified Iosipescu shear and compression fixture. Numerical simulation of the combined shear and compression test was carried out to verify the reliability of the modified device. The numerical results were compared with data from experiments on a medium-density fiberboard. The numerical results show good agreement with the experimental results for the shear test in all the three material directions tested. The shapes as well as the values of the strain fields were similar in the numerical and experimental results. Different rotations of the combined shear and compression device were studied using the finite element method to find the combinations that gave reliable results in shear and compression. It was found that the 45° rotation gave the most uniform strain fields in the section between the notches. This rotation was tested on the fiberboard.  相似文献   
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During refining of mechanical pulp, a process occurring at high speed at temperatures of 140–160°C, the flexibility and bonding ability of wood fibres are increased. To understand the mechanical behaviour of the fibres in this operation, deformations at low speed of wet wood specimens at 50°C were studied under two different combinations of shear and compression loadings. The results were compared with the behaviour of wet wood in pure compression. Some features of the deformation that occurred in earlywood were analysed using an image analysis procedure. During pure compression the cell walls bend independently of the shape of the fibre cells and their cell wall thickness. Under combined shear and compression, however, mainly the corners of the fibre cells get deformed. In a second deformation performed in compression, the fibre cells follow the same deformation pattern as given by the first deformation type whether in compression or in combined shear and compression. The interpretation was that permanent defects in the cells themselves were introduced already in the first load cycle of the wood samples. The load combination with lower shear gave the same permanent strain as the case of pure compression but using less energy.  相似文献   
106.
The main goal of quarry restoration is to convert degraded, unproductive areas into new, self‐sustaining ecosystems that develop into highly natural environments. With the aim to individuate the best practices for restoring limestone quarries, we investigated the short‐term effects on vegetation features and economic advantages of three restoration approaches. These approaches included tree and shrub planting, no herb layer, or a commercial seed mixture or hayseed. The different approaches were tested in a limestone quarry within the Botticino extractive basin (N‐Italy). A donor grassland area of hayseed and a quarry area that had undergone spontaneous revegetation over a decade were used as control areas. We surveyed the vegetation plots to investigate the structure and the productivity of the herbaceous layers; collecting data on plant species cover, the mean plant height, the tree and shrubs mortality and biomass enabled us to perform gradient analysis. The main differences between the sites were due to biotic factors; specifically, vegetation cover was affected quite differently by the different restoration approaches. Restoration with commercial seed mixture resulted primarily in dense stands of Lolium perenne that caused an increase in shrub and tree mortality. Cost–benefit analysis showed that despite hayseed being the most expensive approach in terms of cost and time, it ensured higher species diversity, vegetation structure and greening. Our results highlighted that autochthonous plant materials can improve excavation‐areas restoration by both contrasting the colonisation of non‐native species and increasing natural regeneration and biodiversity levels. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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The effect of technological processing on the contents of eight minerals – i.e., calcium, copper, iron, magnesium, phosphorous, potassium, selenium, and zinc – was investigated in pasta making. Milling of durum wheat as well as pasta making were carried out in a pilot plant by using three different grain samples. Pasta samples purchased on the market were also surveyed to gain information on the mineral content of commercial products. The effect of cooking was also investigated in order to determine the retention of the selected elements in the final ‘ready-to-eat’ product. Analyte concentrations in whole grains, semolina, pasta and cooked pasta were determined by inductively coupled plasma-mass spectrometry.  相似文献   
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Palytoxin (PLTX) is a highly toxic polyether identified in various marine organisms, such as Palythoa soft corals, Ostreopsis dinoflagellates, and Trichodesmium cyanobacteria. In addition to adverse effects in humans, negative impacts on different marine organisms have been often described during Ostreopsis blooms and the concomitant presence of PLTX and its analogues. Considering the increasing frequency of Ostreopsis blooms due to global warming, PLTX was investigated for its effects on Artemia franciscana, a crustacean commonly used as a model organism for ecotoxicological studies. At concentrations comparable to those detected in culture media of O. cf. ovata (1.0–10.0 nM), PLTX significantly reduced cysts hatching and induced significant mortality of the organisms, both at larval and adult stages. Adults appeared to be the most sensitive developmental stage to PLTX: significant mortality was recorded after only 12 h of exposure to PLTX concentrations > 1.0 nM, with a 50% lethal concentration (LC50) of 2.3 nM (95% confidence interval = 1.2–4.7 nM). The toxic effects of PLTX toward A. franciscana adults seem to involve oxidative stress induction. Indeed, the toxin significantly increased ROS levels and altered the activity of the major antioxidant enzymes, in particular catalase and peroxidase, and marginally glutathione-S-transferase and superoxide dismutase. On the whole, these results indicate that environmentally relevant concentrations of PLTX could have a negative effect on Artemia franciscana population, suggesting its potential ecotoxicological impact at the marine level.  相似文献   
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