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101.
The adsorption of ionic Cd has been investigated on three humic acids isolated from podzol, rendzina and brown Mediterranean soils of Tuscany. The adsorption isotherms have been determined at 5 and 25°C. Cadmium adsorption was described by the Langmuir adsorption equation. Langmuir parameters were related to the functional groups content of humic acids and decreased in the following order: rendzina>brown Mediterranean soil>podzol. Adsorption was independent on temperature and increased with pH. Desorption experiments with 0.1 N NH4OAc and 0.25 M Cu (OAc)2 proved that Cd is adsorbed on humic acid about 50% in an exchangeable form and 50% in coordination complexes. 相似文献
102.
Riccardo Riffaldi Renato Levi-Minzi Alessandro Saviozzi Giacomo Vanni Alessandra Scagnozzi 《Water, air, and soil pollution》1993,69(3-4):257-264
A laboratory experiment was performed during a 40-day incubation period in order to evaluate changes in organic and inorganic compounds of soil amended with two doses of sludge obtained from olive-oil processing waste waters. Differences between the amounts of organic components of the amended soil and those of the control, although related to doses and sampling time, disappeared at the end of the experimental period. On the contrary, the inorganic anion contents were still different for the various treatments, which suggest, especially for NO3 ? and SO4 2?, a transient inhibition in the soil-sludge system. A germination test, carried out on the soil amended with different doses of sludge, indicates that after about twenty days even the soil containing the highest dose of sludge did not show toxicity any longer. 相似文献
103.
104.
Giada Morelli Paolo Catellani Riccardo Miotti Scapin Sofia Bastianello Daniele Conficoni Barbara Contiero Rebecca Ricci 《Journal of animal physiology and animal nutrition》2020,104(2):690-697
Feeding raw-meat-based diets to companion animals has become a widespread practice, and many owners are now accustomed to buying frozen ingredients online. The goals of this study were to assess the microbiological quality of raw-meat dog foods obtained from specialized websites and to evaluate the effects of storage at different temperatures for a few days. Twenty-nine raw dog food products were processed for quantitative bacteriology (i.e. total viable count, TVC; Escherichia coli; faecal coliforms, FC) and sulphite-reducing clostridia, and analysed for the presence of Salmonella spp., Listeria monocytogenes, Yersinia enterocolitica and Clostridium difficile. Every sample was examined right after the delivery (T0), after 24 to 48 hr and after 72 hr, both at 2°C and 7°C. At T0, the mean score for the TVC was 5.9 × 106 cfu/g (SD = 4.8 × 107 cfu/g), while those for E. coli and FC were 1.1 × 104 cfu/g (SD = 2.5 × 105 cfu/g) and 3.3 × 103 cfu/g (SD = 6.5 × 104 cfu/g) respectively. The samples stored at 2°C had a significant increase of all parameters (TVC: p < .01; E. coli: p = .03; FC: p = .04) through time. Noteworthy differences between the analyses performed at 2°C and 7°C were found for TVC (p < .01), being the samples considerably more contaminated at higher temperatures. No sample tested positive for Salmonella spp., while L. monocytogenes was isolated from 19 products, Y. enterocolitica from three products and Clostridium perfringens and C. difficile from four and six products respectively. The microbiological quality of raw-meat dog foods sold online appears to be poor, carrying considerable amounts of potentially zoonotic bacteria and reaching greater levels of bacterial contaminations if not kept at proper refrigeration temperatures and fed soon after defrosting. 相似文献
105.
Laura Marconato Damiano Stefanello Matti Kiupel Riccardo Finotello Gerry Polton Federico Massari Roberta Ferrari Chiara Agnoli Ombretta Capitani Chiara Giudice Luca Aresu Maria Elisabetta Vasconi Antonella Rigillo Silvia Sabattini 《Veterinary and comparative oncology》2020,18(3):409-415
Lymph node (LN) metastasis is a negative prognostic factor in dogs with cutaneous mast cell tumours (cMCTs). While elective lymphadenectomy of metastatic LNs improves outcome, the benefit of adjuvant medical therapy in dogs with early metastatic (HN2) LNs is debated. The aim of this retrospective multicentre study was to evaluate the therapeutic benefit of adjuvant medical therapy following surgical removal of the primary low‐grade cMCT (Patnaik grade 1‐2 and Kiupel low‐grade) and lymphadenectomy of HN2 LNs by analysing survival rates and patterns of recurrence. Seventy‐three dogs were included: 42 received adjuvant medical treatment (chemotherapy and/or kinase inhibitors), and 31 did not. The median follow‐up time for medically treated dogs was 619 days: two experienced local recurrence, three nodal relapse and four distant relapse. For dogs undergoing surgery only, the median follow‐up time was 545 days. None of them experienced local recurrence, nodal, or distant relapse. Time to progression was significantly shorter in dogs receiving adjuvant medical treatment (P = .021). A similar tendency was observed for overall survival (P = .056). The current study shows that dogs with low‐grade cMCTs, that undergo surgical excision of the primary tumour and elective lymphadenectomy of the HN2 regional LN harbour a good prognosis. The use of adjuvant medical treatment in these dogs does not seem to provide any benefit in terms of progression and survival. 相似文献
106.
Locatelli C Santini A Bonometti GA Palermo V Scarpa P Sala E Brambilla PG 《The Journal of small animal practice》2011,52(5):246-253
Objectives : To assess the influence of body surface area, age and gender on echocardiographic parameters and to establish echocardiographic reference values for dogue de Bordeaux dogs. Methods : Thirty‐nine healthy dogue de Bordeaux dogs of both sexes, older than one year, were recruited and 31 of these were included in the study. The classic linear regression model proved to be the best way to analyse the data. The reference limits of the echocardiographic measurements were calculated using the regression equations. The difference between the mean values of body surface area in both gender groups was evaluated by using one‐way ANOVA. Results : A significant correlation was seen between several echocardiographic parameters and body surface area or body surface area and age, and high coefficients of determination (R2) were found. No effect of gender was detected on echocardiographic variables, except for the thickness of the left ventricular posterior wall at end diastole. Clinical Significance : The echocardiographic parameters related to body surface area, in the absence of correlation with other independent variables (gender and age) should be interpreted with caution because their variation could be significant for the presence of heart disease. The proposed statistical model allows estimation of echocardiographic parameters in dogue de Bordeaux dogs with different body surface areas and ages. 相似文献
107.
Differential expression of microRNA-206 in skeletal muscle of female Piedmontese and Friesian cattle 总被引:1,自引:0,他引:1
Miretti S Martignani E Taulli R Bersani F Accornero P Baratta M 《Veterinary journal (London, England : 1997)》2011,190(3):412-413
The double-muscle phenotype is an inherited condition in Piedmontese cattle traced to a point mutation in the myostatin gene. To investigate the potential role of muscle-specific miRNAs in determining muscle development in cattle, this study examined the patterns of expression of microRNAs (miRNA-1) and miRNA-206 in Piedmontese and Friesian cattle according to phenotype and sex. There were no significant differences in miRNA-1 expression between different muscle phenotypes, sexes or breeds, whereas there was significantly higher expression of miRNA-206 in female Piedmontese compared with female Friesian cattle. 相似文献
108.
Fiaccadori R Cicognani E Alberoni G Collina M Brunelli A 《Pest management science》2011,67(5):535-540
BACKGROUND: Venturia inaequalis (Cooke) Winter with reduced sensitivity to strobilurins has been reported in several countries, including Italy. This study aimed to characterise the sensitivity to strobilurins of three different types of V. inaequalis population: (a) wild types; (b) from commercial orchards satisfactorily managed with strobilurins; (c) from an experimental orchard with control failures by trifloxystrobin and kresoxim‐methyl. In vitro sensitivity tests included antigerminative activity on population conidia and mycelial growth inhibition on monoconidial isolates. Cleaved amplified polymorphic sequence (CAPS) analysis was used for the detection of G143A substitution. RESULTS: Wild‐type populations showed EC50 values lower than 0.031 mg L?1, while those of orchards with good performance by strobilurins presented EC50 values never higher than 0.063 mg L?1. Samples with scab control failures showed a strongly reduced population sensitivity. Similar differences were confirmed in monoconidial isolates. The G143A substitution was always detected in low‐sensitivity populations, only sometimes in well‐controlled populations and generally not in wild types. CONCLUSIONS: In vitro sensitivity assays were able to discriminate the three population types with different scab management, while the qualitative PCR analysis (CAPS) was only partially reliable. High sensitivity differences among V. inaequalis populations with good and poor field control by strobilurins were observed. Copyright © 2011 Society of Chemical Industry 相似文献
109.
Europe's terrestrial biosphere absorbs 7 to 12% of European anthropogenic CO2 emissions 总被引:2,自引:0,他引:2
Janssens IA Freibauer A Ciais P Smith P Nabuurs GJ Folberth G Schlamadinger B Hutjes RW Ceulemans R Schulze ED Valentini R Dolman AJ 《Science (New York, N.Y.)》2003,300(5625):1538-1542
Most inverse atmospheric models report considerable uptake of carbon dioxide in Europe's terrestrial biosphere. In contrast, carbon stocks in terrestrial ecosystems increase at a much smaller rate, with carbon gains in forests and grassland soils almost being offset by carbon losses from cropland and peat soils. Accounting for non-carbon dioxide carbon transfers that are not detected by the atmospheric models and for carbon dioxide fluxes bypassing the ecosystem carbon stocks considerably reduces the gap between the small carbon-stock changes and the larger carbon dioxide uptake estimated by atmospheric models. The remaining difference could be because of missing components in the stock-change approach, as well as the large uncertainty in both methods. With the use of the corrected atmosphere- and land-based estimates as a dual constraint, we estimate a net carbon sink between 135 and 205 teragrams per year in Europe's terrestrial biosphere, the equivalent of 7 to 12% of the 1995 anthropogenic carbon emissions. 相似文献
110.
An experiment was conducted over 12 months using field-grown olive trees (Olea europaea) to assess the combined effect of soil water availability and fruit number on seasonal changes in leaf nitrogen (N) concentration. Three irrigation regimes were established and three trees per irrigation treatment were thinned to reduce their yield to about half that of unthinned trees. The N concentration of fully-expanded leaves from either the current-year growth or one-year old part of fruiting shoots was determined every two months. Nitrogen concentration was higher in current-year leaves than in one-year old ones at most sampling dates. Maximum values of leaf N were measured in spring, minimum values in August. Leaf N concentrations were positively correlated with leaf water potential during fruit development. This relationship was weak at the onset of rapid oil accumulation in August and became more evident at harvest. There was no correlation between leaf N and crop level. 相似文献