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排序方式: 共有468条查询结果,搜索用时 15 毫秒
21.
Petterino C Luzio E Baracchini L Ferrari A Ratto A 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2011,40(1):89-94
A 7-year-old male German Shepherd dog in poor body condition had a 3-month history of intermittent hematuria. Nonregenerative anemia, mild leukocytosis, marked hypoalbuminemia, and hematuria were observed. Subsequently, marked neutrophilia and moderate monocytosis were noted; anemia, hypoalbuminemia, and hematuria persisted; and the dog developed disseminated intravascular coagulation. Ultrasonographic examination of the abdomen revealed the presence of an enlarged and irregularly shaped right kidney with a large area of cavitation, and a nephrectomy was performed 30 days after initial examination. Cytologic examination of fine-needle aspirates and imprints of the right kidney revealed a neoplastic cell population suggestive of renal carcinoma. The histopathologic diagnosis was chromophobic cystic-papillary renal carcinoma. The tumor cells expressed granulocytic/macrophage-colony-stimulating factor (GM-CSF), detected by immunohistochemical staining, and elaboration of GM-CSF by the tumor may have mediated the leukocytosis in this dog. Following excision of the tumor, neutrophil and monocyte counts were only mildly increased. The dog died 135 days after initial presentation, and a necropsy was not permitted. Paraneoplastic neutrophilic leukocytosis is an uncommon finding and may be caused by elaboration of CSF by neoplastic cells. 相似文献
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23.
Mariarita Romanucci Laura Bongiovanni Anita Russo Silvia Capuccini Luca Mechelli Laura Ordeix Leonardo Della Salda 《Veterinary dermatology》2011,22(1):31-38
Zinc deficiency causes skin diseases both in humans and in animals. The underlying pathogenic mechanisms remain unclear, but a growing body of evidence indicates a role for zinc in skin protection against free radical‐induced oxidative damage. The immunohistochemical expression of heat shock proteins (HSPs; Hsp27, Hsp72, Hsp73 and Hsp90), Cu/Zn superoxide dismutase (SOD), metallothionein (MT), Ki‐67 antigen and active caspase‐3 were evaluated in normal canine skin and in samples from eight dogs with zinc‐responsive dermatosis. All investigated HSPs showed intense cytoplasmic immunostaining in the affected epidermis. Focal nuclear positivity of Hsp72 was also detected in keratinocytes. Although Cu/Zn SOD expression was similar to that observed in normal skin, MT immunoreactivity occurred in both the cytoplasm and the nucleus of basal cells in normal skin but was absent from the affected epidermis. Caspase‐3 activation was also absent in the involved epidermis, which revealed a high Ki‐67 index (a 3.5‐ to 9‐fold increase compared with normal skin). These results support the hypothesis that cellular response to stress, particularly oxidative stress, is involved in the pathogenesis of skin lesions in canine zinc‐responsive dermatosis. The lack of MT immunoreactivity in the affected epidermis may be indicative of low zinc levels, thus resulting in vulnerability to oxidative damage. In contrast, high expression levels of HSPs in skin during zinc deficiency may confer protection against a variety of dangerous stimuli, contributing to inhibition of apoptosis and to cell cycle regulation of proliferating keratinocytes. 相似文献
24.
Every year raw tobacco and manufactured tobacco products are lost to two major storage pests, the cigarette beetle, Lasioderma serricorne (F) and the tobacco moth, Ephestia elutella (Hiibner). Post-harvest management of both insects is achieved through sanitation, insect monitoring and fumigation with phosphine. However, insect resistance to phosphine and control failures have been reported, and fumigants are under constant regulatory pressure. Here we report the evaluation of spinosad, a bioinsecticide derived from the fermentation of the soil micro-organism Saccharopolyspora spinosa Mertz & Yao. Spinosad was first registered in 1997 and is now widely used as a field pest control agent on many crops, including tobacco. The insecticidal activity of the fermentation product (technical spinosad, TS) was measured by diet incorporation assays against L serricorne and E elutella larvae. Mortality levels were determined on newly hatched larvae and over the whole insect life cycle. For both species, no emergence of adult insects was observed in cured tobacco sprayed with 50mg TS kg(-1) and inoculated with eggs or newly hatched larvae. These results indicated that spinosad has potential for the control of both species in stored tobacco, since 100% control of both pests could be achieved at 50 mg TS kg(-1), and with almost full control (90-95%) at 10 mg kg(-1). We also monitored the stability of the product on cured tobacco. The original concentration of the main active component of TS, spinosyn A, did not change significantly over 18 months, indicating no loss of spinosad during a typical leaf storage period of time. Bioassays against larvae confirmed that the bioinsecticidal activity of spinosad was retained. 相似文献
25.
Stacy L. Anderson Luca Panizzi Jose Bracamonte 《The Canadian veterinary journal. La revue veterinaire canadienne》2014,55(2):152-155
An 8-month-old Andalusian filly was treated for jejunal perforations due to ingestion of a porcupine quill. During exploratory laparotomy, 2 separate stapled side-to-side jejunojejunal resection and anastomoses were performed. Post-operative complications after 2 years follow-up included mild incisional herniation following incisional infection and chronic intermittent colic. 相似文献
26.
Pasquale Borrelli Panos Panagos Cristiano Ballabio Emanuale Lugato Melanie Weynants Luca Montanarella 《Land Degradation \u0026amp; Development》2016,27(4):1093-1105
Understanding spatial and temporal patterns in land susceptibility to wind erosion is essential to design effective management strategies to control land degradation. The knowledge about the land surface susceptible to wind erosion in European contexts shows significant gaps. The lack of researches, particularly at the landscape to regional scales, prevents national and European institutions from taking actions aimed at an effective mitigating of land degradation. This study provides a preliminary pan‐European assessment that delineates the spatial patterns of land susceptibility to wind erosion and lays the groundwork for future modelling activities. An Index of Land Susceptibility to Wind Erosion (ILSWE) was created by combining spatiotemporal variations of the most influential wind erosion factors (i.e. climatic erosivity, soil erodibility, vegetation cover and landscape roughness). The sensitivity of each input factor was ranked according to fuzzy logic techniques. State‐of‐the‐art findings within the literature on soil erodibility and land susceptibility were used to evaluate the outcomes of the proposed modelling activity. Results show that the approach is suitable for integrating wind erosion information and environmental factors. Within the 34 European countries under investigation, moderate and high levels of land susceptibility to wind erosion were predicted, ranging from 25·8 to 13·0 M ha, respectively (corresponding to 5·3 and 2·9% of total area). New insights into the geography of wind erosion susceptibility in Europe were obtained and provide a solid basis for further investigations into the spatial variability and susceptibility of land to wind erosion across Europe. © 2014 The Authors. Land Degradation and Development published by John Wiley & Sons, Ltd. 相似文献
27.
Alessandro Infantino Mohamed Kharrat Luca Riccioni Clarice J. Coyne Kevin E. McPhee Niklaus J. Grünwald 《Euphytica》2006,147(1-2):201-221
Summary Soil-borne fungal diseases are among the most important factors, limiting the yield of grain legumes in many countries worldwide.
Root rot, caused by Aphanomyces euteiches, Rhizoctonia solani, Fusarium solani and wilt, caused by several formae speciales of Fusarium oxysporum are the most destructive soil-borne diseases of pea, chickpea, lentil, fababean and lupin. The most effective control of
these diseases is achieved through the use of resistant varieties. In this paper, recent advances in conventional and innovative
screening methods for disease resistance are presented. Many grain legume accessions, which are maintained in national and
international germplasm collections, have been evaluated for disease resistance and numerous resistant varieties have been
released following incorporation of identified resistance genes from these sources. Recent identification of molecular markers
tightly linked to resistance genes has greatly enhanced breeding programs by making marker assisted selection (MAS) possible
and allowing the development of varieties with multiple disease resistance. Progress in the understanding of the biology of
soil-borne fungal pathogens of grain legumes is also reviewed with particular reference to the genetic structure of their
populations, diagnosis and host–pathogen interaction. 相似文献
28.
Amrein TM Lukac H Andres L Perren R Escher F Amadò R 《Journal of agricultural and food chemistry》2005,53(20):7819-7825
The influences of composition and roasting conditions on acrylamide formation in almonds and hazelnuts were investigated. Eighteen samples of almonds originating from the U.S. and Europe were analyzed for sugars and free amino acids, and acrylamide formed during roasting was determined. Asparagine was the main free amino acid in raw almonds and correlated with the acrylamide content of dark roasted almonds. Roasting temperature was another key factor and had a very strong influence on acrylamide formation. Almonds of European origin contained significantly less free asparagine and formed significantly less acrylamide during roasting as compared to the almonds from the U.S. Roasted hazelnuts contained very little acrylamide because of the low content of free asparagine in the raw nut. Reducing sugars, although being consumed much faster than free amino acids in both types of nuts, were not decisive for the extent of acrylamide formation during roasting. 相似文献
29.
30.
Rastrelli L Passi S Ippolito F Vacca G De Simone F 《Journal of agricultural and food chemistry》2002,50(20):5566-5570
Changes in the concentration of tocopherol, monophenols, o-diphenols, squalene, and polyunsaturated fatty acids in olive oil were evaluated during 1 year at various storage conditions. Samples of two different extra virgin olive oil (EOO), produced in Calabria (Italy), were stored in dark and in colorless bottles, filled up completely or to half, in order to simulate the domestic storage conditions. The extent of oxidation or photooxidation was monitored by periodic measurements of peroxide values and the rate of degradation of alpha-tocopherol, o-diphenols, squalene, and polyunsaturated fatty acids. The quantitative analysis of the constituents has been performed by HPLC-DAD, HPLC-MS, and GC-MS. The main changes in the concentrations of the analyzed compounds were associated with the major oxygen level in the half-empty glass bottles. alpha-Tocopherol was the first molecule to be oxidized (-20% after 2 months, -92% after 12 months). Squalene and o-diphenols were protected in the first months by the presence of alpha-tocopherol, and their content decreased significantly only after 6 and 8 months, respectively, in the half-empty bottles. The concentration of polyunsaturated fatty acids remained almost constant during 8 months for all four different storage conditions; their oxidation started when the level of the antioxidants decreased. 相似文献