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排序方式: 共有602条查询结果,搜索用时 15 毫秒
91.
Gelaleti GB Jardim BV Leonel C Moschetta MG Zuccari DA 《Veterinary immunology and immunopathology》2012,146(2):106-112
Mammary gland tumors in female dogs are an excellent model for the clinic-pathological, diagnostic and prognostic investigation of mammary neoplasias. Prognostic and predictive markers are effective in research and routine diagnosis. Interleukins play a fundamental role in cancer, with a particular function in tumor growth, invasion and metastatic potential. Interleukin-8 (IL-8) is known to possess tumorigenic and pro-angiogenic properties, and its overexpression is seen in a number of human tumors. IL-8 serum levels were determined and correlated with the clinic-pathological features and clinical evolution of mammary gland neoplasias in female dogs. IL-8 was measured by an immunoenzymatic assay in 30 female dogs with mammary neoplasias within a 12 month follow-up and in 50 control animals. The correlation between IL-8 concentration and clinical parameters was investigated. A statistically significant difference in the IL-8 serum levels was found in tumor-bearing dogs compared to the controls. In addition, when the individual parameters were evaluated, IL-8 content showed a positive correlation with the tumor progression, lymph node involvement, recurrence and death. Single and multivariate analyses showed associations between tumor recurrence, metastasis, high clinical staging and high IL-8, and also with the death risk. This was also consistent with the high IL-8 content in dogs showing tumor recurrence and metastasis. IL-8 superexpression has been detected in a number of human tumors, usually associated with a poor prognostic. Besides promoting angiogenesis, IL-8 is strongly related with the metastatic phenotype of mammary tumor cells. High IL-8 concentration was found in mammary gland cancer patients with advanced disease stages. Our results show that IL-8 can be used as a non-invasive prognostic marker for mammary gland cancer, and can be useful for the prediction of disease progression and recurrence in dogs with mammary neoplasias. The increased level of this cytokine acts as an independent prognostic marker of survival and the identification of animals with the poor prognostic. 相似文献
92.
Mueller CA Broz P Müller SA Ringler P Erne-Brand F Sorg I Kuhn M Engel A Cornelis GR 《Science (New York, N.Y.)》2005,310(5748):674-676
Many pathogenic bacteria use injectisomes to deliver effector proteins into host cells through type III secretion. Injectisomes consist of a basal body embedded in the bacterial membranes and a needle. In Yersinia, translocation of effectors requires the YopB and YopD proteins, which form a pore in the target cell membrane, and the LcrV protein, which assists the assembly of the pore. Here we report that LcrV forms a distinct structure at the tip of the needle, the tip complex. This unique localization of LcrV may explain its crucial role in the translocation process and its efficacy as the main protective antigen against plague. 相似文献
93.
Cocchi M Franchini G Manzini D Manfredini M Marchetti A Ulrici A 《Journal of agricultural and food chemistry》2004,52(13):4047-4056
A comparison of different digestion procedures has been carried out for the analysis of metal concentration in samples of vinegars and Aceto Balsamico Tradizionale of Modena (ABTM) coming from an unique barrel set. In particular, classical wet, dry ashing, and closed vessel microwave digestion procedure have been utilized and compared for each investigated species. In a few cases, direct metal determination on ABTM (without treatment procedure) is proposed as possible alternative to sample manipulation. Flame atomic absorption spectrometry was used for the quantification of iron and zinc, while graphite furnace atomic absorption spectrometry was used for all the other elements (i.e., chromium, manganese, cobalt, nickel, copper, cadmium, and lead). The comparison among the different sample treatments was carried out by the use of statistical and chemometric tools. In particular, principal component analysis and ANOVA approaches were used to discriminate between the diverse analytical methods. Furthermore, for all the dissolving techniques, the analytical metal recovery was always evaluated by the application of the recovery function on the same sample matrix. In general, the recoveries were fairly good, ranging from 90 to 103%, except for Cd and Pb with dry ashing, which showed recovery values close to 55% and 67%, respectively. As regards the metals concentration of the investigated samples, the experimental data reveal for some species the presence of concentration slightly over the legal limit fixed for wine and wine vinegar. 相似文献
94.
Cadar D Cságola A Spinu M Dán A Ursu K Lorincz M Tuboly T 《Acta veterinaria Hungarica》2010,58(4):475-481
Porcine circoviruses (PCV) are widespread in domestic pigs worldwide and there is growing information about the presence of PCV in other suid species. Based on serological studies with sera of wild boars, it was established that PCV1 was present in these animals and antibodies specific to PCV2 were also detected in wild boars living in captivity or in sylvatic areas, both with or without clinical signs of PMWS. Studies including PCV2 genome or antigen detection confirmed the previous findings. This is the first report about the presence of PCV in Transylvanian wild boar populations. Four hundred and sixty-nine samples were collected and grouped according to geographic origin, tested for the presence of PCV DNA using a real-time quantitative polymerase chain reaction assay, and 13.52% of the animals proved to be positive for one or in three cases both of the PCV genotypes. PCV2 was detected in all of the PCV-positive samples. 相似文献
95.
96.
Pesticides’ sublethal effects are not regularly taken into account when assessing agrochemical’s toxicity. With the objective of detecting chronic, sublethal effects of the widely used herbicide glyphosate, an experiment was performed using the earthworm Eisenia fetida as model organism. Earthworm adults were randomly assigned to three glyphosate treatments: control (no glyphosate), regular dose for perennial weeds, and double dose. Six E. fetida individuals were placed in each pot. Two random pots were taken weekly from each treatment and the number of adults, individual weight, number of cocoons, and presence and number of young earthworms were recorded. A matrix analysis was performed with the data. The matrix population model built showed that while the control population had a positive growth rate, both glyphosate treatments showed negative growth rates. The results suggest that under these sublethal effects, non-target populations are at risk of local extinction, underscoring the importance of this type of studies in agrochemical environmental risk assessment. 相似文献
97.
Jonathan M. Plett Marina Cvetkovska Patricia Makenson Tim Xing Sharon Regan 《Physiological and Molecular Plant Pathology》2009,74(1):18-26
Ethylene is a central signalling agent in mediating plant defence against pathogens. Mutations to the ethylene receptor ETR1 have been shown to alter susceptibility of plants to mycotoxin-induced cell death. Using Fumonisin B1 (FB1) to induce cell death, we demonstrate that the receptor mutant ein4-1 has a reduced rate of necrosis, potentially due to an upregulation of ETHYLENE RESPONSE FACTOR1. Mutations in other ethylene receptors differentially affected the expression of genes in the jasmonic and salicylic acid defence pathways. Together these data indicate that ethylene receptors do not have redundant roles in mediating FB1-induced cell death. 相似文献
98.
Giulia Alberoni Davide Cavallini Marina Collina Agostino Brunelli 《European journal of plant pathology / European Foundation for Plant Pathology》2010,126(4):453-457
Up to 2005 the sensitivity of Stemphylium vesicarium (Wallr.) Simm., the causal agent of pear brown spot, to the strobilurin fungicides kresoxim-methyl, trifloxystrobin and pyraclostrobin
was still comparable with baseline values associated with good efficacy in the field. During 2006, the first resistant isolates
were detected in two commercial pear orchards in the Emilia-Romagna region (Italy), one of which was affected by considerable
control failure linked to strobilurin treatments as demonstrated in a field trial. In vitro sensitivity tests with 0.5 mg l−1 of kresoxim-methyl, trifloxystrobin and pyraclostrobin showed that in the population collected in the orchard with control
failure the conidial germination was greater than 90% compared to an untreated control both in 2006 and in 2007, i.e. 1 year
after the suspension of strobilurin applications. In the other orchard, where only a few symptomatic fruits were found and
the strobilurins were still in use, the conidial germination was lower, about 50% in 2006 and 25% in 2007. The molecular analysis
of mitochondrial cytochrome b gene of some monospore isolates with different levels of sensitivity confirmed the presence
of the mutation causing G143A substitution in all the resistant isolates. In conclusion, both in vitro tests and molecular
analysis confirmed the first occurrence of Stemphylium vesicarium resistance to all strobilurin fungicides tested. 相似文献
99.
Leah Tsror Valerie Hélias Sara Mordechai-Lebiush Orly Erlich Marina Hazanovsky Laura Chalupowicz Michal Reuven Orit Dror Lea Valinsky Angelique Laurent Shulamit Manulis-Sasson 《Plant pathology》2021,70(9):2179-2187
Pectobacterium brasiliense (Pbr) infects a wide range of crops worldwide, causing potato blackleg and soft rot and vegetable soft rots. This study aimed to characterize the genetic diversity and virulence variability among 68 Pbr strains isolated from either symptomless potato progeny tubers, diseased potato plants, ware potatoes wash water, or vegetables grown in Israel, as well as strains isolated from symptomless seed tubers grown in Europe, or diseased potato plants grown in France. The collection was typed using PCR and TaqMan real-time PCR analyses, dnaX sequence analysis, pulsed-field gel electrophoresis (PFGE), and pectolytic activity. dnaX phylogeny grouped almost all strains in a common genetic clade related to Pbr, which was distinct from the other Pectobacterium species. PFGE analysis identified two main clusters, including one major group of 47 strains with 95%–100% similarity. Maceration assays on two potato cultivars showed significant differences between strains but with no correlations with the source of the strains nor the status of the host (with/without symptoms). Molecular (dnaX sequences and PFGE profiles) and phenotypic analyses (tuber maceration tests) showed that the tested Pbr strains are not a homogeneous group. Analysis of the tested Pbr strains isolated from potato and vegetables grown in fields with a history of potato cultivation suggests that seed tubers imported from Europe may be the main source for Pbr in Israel. To the best of our knowledge, this is the first study that describes biodiversity and population structure of P. brasiliense isolated from potato and vegetables under hot climate conditions. 相似文献
100.
von Allem-Balmelli M 《Schweizer Archiv für Tierheilkunde》2011,153(4):202-203