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21.
In order to investigate the occurrence of Campylobacter, Helicobacter and Arcobacter species in caecal contents of rabbits reared in intensive and rural farms, a total of 87 samples from animals belonging to 29 farms were analysed by both cultural and PCR analyses.  相似文献   
22.
Hunger and health among undocumented Mexican migrants in a US urban area   总被引:1,自引:0,他引:1  
OBJECTIVES: To measure the occurrence and correlates of hunger and to evaluate the association between hunger and three health indicators among undocumented Mexican immigrants. DESIGN: Non-probability cross-sectional sample. SETTING: Neighbourhoods within New York City. SUBJECTS: Four hundred and thirty-one undocumented Mexican immigrants living in the USA. RESULTS: Hunger was indicated by approximately 28% of respondents. In a multivariate model, working as a day labourer was associated with hunger (odds ratio (OR) 3.33, 95% confidence interval (CI) 1.83-6.06) while receiving public assistance protected against hunger (OR 0.23, 95% CI 0.06-0.88). In multivariate models, respondents who reported experiencing hunger also reported poorer overall health (OR 1.69, 95% CI 0.95-3.02) and more days of poor mental (P = 0.045) and physical health (P < 0.0001). Greater amount of time lived in the USA was also associated with worse overall health (P = 0.054) and more days of poor mental and physical health (P < 0.01). CONCLUSIONS: The present study shows that food insecurity and hunger may be problems among undocumented migrants living in the USA. Uncertain and unpredictable work schedules and limited access to public assistance may contribute to high levels of hunger, which in turn may also negatively affect mental and physical health. Increasing amount of time lived in the USA is also associated with poorer health indicators. Programmes that provide undocumented migrants with emergency access to resources may reduce food insecurity and lead to improved health outcomes among this vulnerable population.  相似文献   
23.
The introduction of the American eastern grey squirrel (Sciurus carolinensis) in Europe is causing a dramatic decline of the native European red squirrel (Sciurus vulgaris), due to competition. We used spatially explicit population dynamics models to illustrate the potential expansion of the grey squirrel from Italy, the only continental country with the species, into neighbouring countries. Simulations started with the known grey squirrel distributions in 1996 and modelled the spread for the next 100 years in two different scenarios. One “best case” in which a random seed crop pattern of poor, good and mast seed crops was simulated with concomitant effects on squirrel fecundity and mortality and one “worst case” scenario in which poor years were not included. In the best case scenario, it will take 30-40 years for grey squirrels to start invading the Alps and about 70-75 years to cross the border between Italy and France. First populations in Switzerland are predicted in 2051-2066. In the worst case scenario, the spread will be significantly faster: the species is predicted to reach France in 2026-2031 and Switzerland in 2031-2041. Removing two of the three populations of grey squirrel will likely postpone the invasion of Switzerland but not of France. Large areas of Europe contain potentially good habitat for grey squirrels, and expansion from Italy, to France, Switzerland and belong to most of Eurasia is simply a matter of time. This will represent a serious risk for the conservation of the native red squirrel and will have implications for national forest operations. However, a European policy towards introduced species is still lacking. There is therefore a need for a co-ordinated European approach to the management of the grey squirrel and other introduced species.  相似文献   
24.
Canine monocytic ehrlichiosis (CME) caused by Ehrlichia canis is the most known canine tick-borne disease (TBD) spread throughout the world. Preventing tick bites is a priority to reduce the risk of TBDs and it was the aim of the present study to evaluate the efficacy of a combination of imidacloprid 10% and permethrin 50% (ImPer) (Advantix; Bayer AG, Germany) in a spot-on formulation to control CME under field conditions. On January-March 2005, 845 dogs from two kennels in southern Italy (kennels of Bari (KB)- and Ginosa (KG)), with a history of tick infestation were initially tested by serology and PCR assay for E. canis infection. Data on Leishmania infantum infection were also available from a previous study carried out on the same dog population. One hundred twenty-six dogs (14.9%) presented anti-E. canis antibodies with a relative prevalence of 15.6% (n=65 dogs in KB) and 14.2% (n=61 dogs in KG). Five hundred thirty-five animals found negative both for E. canis and L. infantum infections were enrolled in three groups (Group A--treated with ImPer once a month; Group B--treated every 2 weeks; and Group C--untreated control animals) and monitored for E. canis infection by serology and PCR in November 2005 (first follow-up) and in March 2006 (second follow-up). The E. canis infection was serologically revealed, at the first and/or second follow-up, in 26 animals from Group C in KB and KG (mean incidence density rate (IDR), 13.24%) while in none of the animals from Group A (KB and KG) and only in one animal from Group B (IDR 1.13%) in KG. The final protection efficacy of ImPer ranged from 95.57% to 100% in Groups B and A. At PCR only 15 dogs from KG were positive for Rickettsiales only at the first follow-up and at the sequence analysis two (both in Group C) revealed 100% homology with E. canis sequences while 13 with Anaplasma platys. Four out of 13 A. platys PCR-positive dogs were also seropositive for E. canis at one or both follow-ups. ImPer, by virtue of its repellent and acaricidal activity against ticks, has been shown to be efficacious to prevent E. canis infection in treated dogs living under natural conditions in endemic areas.  相似文献   
25.
Antibody phage display libraries are a useful tool in proteomic analyses. This study evaluated an antibody recombinant library for identification of sex-specific proteins on the sperm cell surface. The Griffin.1 library was used to produce phage antibodies capable of recognizing membrane proteins from Nelore sperm cells. After producing soluble monoclonal scFv, clones were screened on Simental sperm cells by flow cytometry and those that bound to 40–60% of cells were selected. These clones were re-analyzed using Nelore sperm cells and all clones bound to 40–60% of cells. Positive clones were submitted to a binding assay against male and female bovine leukocytes by flow cytometry and one clone preferentially bound to male cells. The results indicate that phage display antibodies are an alternative method for identification of molecules markers on sperm cells.  相似文献   
26.
Field isolates of Mycosphaerella fijiensis, causing black Sigatoka of banana, were characterised for their sensitivity to different inhibitors of the cytochrome bc1 enzyme complex (Qo respiration inhibitors, strobilurin fungicides), using physiological, biochemical and molecular genetic methods. Strobilurin‐resistant isolates exhibited very high resistance factors both in mycelial growth inhibition and NADH consumption assays. Cross‐resistance was observed among all Qo inhibitors, including trifloxystrobin, azoxystrobin, famoxadone, strobilurin B and myxothiazol. However, the Qi and the cytochrome aa3 inhibitors, antimycin A and potassium cyanide, respectively, were not cross‐resistant to Qo inhibitors. In sensitive but not in resistant isolates, mixtures of Qo inhibitors and SHAM, an inhibitor of the alternative oxidase (AOX), were more active than the components alone, indicating that the alternative pathway is essential in metabolism, but not causal for resistance. In the cell‐free NADH‐consumption assay, the Qo inhibitors affected the sensitive but not the resistant isolates, suggesting that AOX was not active in sub‐mitochondrial particles. In whole cells, however, the AOX has a basic expression level and is probably not inducible by trifloxystrobin. Sequencing of the cytochrome b gene of sensitive and resistant M fijiensis isolates revealed a difference in the nucleotide sequence leading to a single amino acid change from glycine to alanine at position 143 in the resistant isolate. This change is known to occur also in the naturally tolerant basidiomycete Mycena galopoda. It is suggested that the field isolates of M fijiensis can acquire resistance to Qo inhibitors due to a target site alteration with a single base pair change. Resistant isolates do not seem to contain a mixture of mutated and non‐mutated DNA, indicating a complete selection of resistant mitochondria and a maternally donated mode of resistance. © 2000 Society of Chemical Industry  相似文献   
27.
Enzyme-derived products obtained from thio-functionalised glucosinolates showed high fungitoxicity, a wide activity spectrum and special physicochemical properties, which suggest their potential as alternatives to commercial fumigants for controlling several soil-borne pathogens. © 1999 Society of Chemical Industry  相似文献   
28.
The F‐lectin, a fucose‐binding protein found from invertebrates to ectothermic vertebrates, is the last lectin family to be discovered. Here, we describe effects of two different types of stressors, bacterial infection and confinement stress, on the modulation of European sea bass Dicentrarchus labrax (L.) F‐lectin (DlFBL), a well‐characterized serum opsonin, using a specific antibody. The infection of the Vibrio alginolyticus bacterial strain increased the total haemagglutinating activity during the 16‐day testing period. The DlFBL value showed an upward regulation on the first, second and last days and underwent a slight downward regulation 4 days post‐challenge. In contrast, the effect of confinement and density stress showed a decrease in the plasma concentration of lectin, ranging from 50% to 60% compared with the control. The modulation of DlFBL is in line with the hypothesis that humoral lectins could be involved and recruited in the initial recognition step of the inflammation, which leads to agglutination, and the activation of mechanisms responsible for killing of the pathogens.  相似文献   
29.
Hydrophobic modified vermiculite mixed with soil was investigated in biodegradation experiments of naphthalene and anthracene. The experiments had been carried out on mixtures of soil and vermiculite at a proportion of 2%, 10%, and 15% and also in the absence of clay used for control. Biodegradation of the pollutants was followed by the decline of naphthalene and anthracene concentration, measured by CG. Compound mineralization was also proved by the evolution of CO2. The results showed that in the mixture with a higher proportion of vermiculite biodegradation is enhanced compared to that performed in the absence of vermiculite. In general, when vermiculite proportions are increased, the rate of degradation increases, which may account for the bioavailability of compounds. Bioavailability is an important factor for the degradation of compounds with low solubility. Comparison of biodegradation rates shows that naphthalene is degraded faster than anthracene. The chemical structure could be responsible for this observation. However, although we did not identify the microorganism that was in the soil, we can conclude that vermiculite could be an alternative for the bioavailability of such compounds. Vermiculite in the modified form could also be very useful as a barrier to retain organic pollutants in accidental spills.  相似文献   
30.
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