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41.
Luigia Sabatini Anna Pianetti Elivio Sisti Paolo Fonti Francesca Bruscolini 《Water, air, and soil pollution》2004,156(1):97-112
This study compares the detection of faecal contamination indicators in irrigation water (25 samples) by two analytical techniques: multiple tube fermentation method (MPN) and Colilert/Enterolert Quanti-Tray system. Our aim was to investigate variations in the test results and determine whether variations could be related to 1) the interval of time between the sample collection and analysis and 2) the manual labour of the operator. Each water sample was analysed at specific intervals of time from the sample collection within 24 h and by three different operators. Statistical analysis was employed to evaluate the results. We have proved that the indices obtained with the multiple tube fermentation method show greater variation than the values obtained with the Colilert and Enterolert systems. Furthermore, some samples, analysed by the MPN method, showed different values, but not statistically significant, in relation to the intervals of time between the sample collection and analysis and in relation to the data obtained by the manual labour of the operators. Values for the same sample varied in respect to legislative limits. The Colilert and Enterolert systems for the detection of indicator bacteria could be a substitute for the standard methods. This procedure could be used for monitoring the quality of irrigation water. 相似文献
42.
Lanciotti R Belletti N Patrignani F Gianotti A Gardini F Guerzoni ME 《Journal of agricultural and food chemistry》2003,51(10):2958-2963
The aims of this work were to evaluate the effects of different concentrations of hexanal, (E)-2-hexenal, hexyl acetate, and their mixtures on the fate of pathogenic species such as Escherichia coli, Salmonella enteritidis, and Listeria monocytogenes inoculated in model systems as well as the antimicrobial activity against the target species of the chosen molecules when added to the packaging atmosphere of inoculated fresh-sliced apples. The result obtained in this work pointed out the potential use of compounds such as hexanal, (E)-2-hexenal, and hexyl acetate for both the extension of shelf life and an improvement of hygienic safety of "minimally processed foods". In fact, hexanal, (E)-2-hexenal, and hexyl acetate had a significant inhibitory effect against pathogen microorganisms frequently isolated from raw materials (E. coli, S. enteritidis, and L. monocytogenes) when inoculated in both model and real systems. In this last condition, these compounds, at the levels used (150, 150, and 20 ppm for hexanal, hexyl acetate, and (E)-2-hexenal, respectively), displayed a bactericide effect on L. monocytogenes and they exhibited significant extensions of lag phase of E. coli and S. enteritidis inoculated at levels of 10(4)-10(5) CFU/g. 相似文献
43.
Ranalli A Pollastri L Contento S Di Loreto G Iannucci E Lucera L Russi F 《Journal of agricultural and food chemistry》2002,50(13):3775-3779
The contents of triacylglycerols and diacylglycerols in three kinds of olive fruit oils (pulp, seed, and whole fruit) were determined. The fatty acid composition and the quality ratios 1,2-diacylglycerols/1,3-diacylglycerols and 1,2-diacylglycerols/total diacylglycerols were also assessed. Seven major Italian olive varieties were considered. Results of univariate statistical analyses indicated that the above analytical parameters (glyceridic ratios excepted) were effective in discriminating between pulp and seed oils. The seed oil fraction did not determine any change in the glyceridic indices and the acylglycerol or fatty acid composition concerning the whole fruit oil (mixture of pulp and seed oil fractions), the weight (%) of seed ( approximately 2%) being by far lower than the weight (%) of pulp ( approximately 85%) (fruit weight basis). Based on the data of triacylglycerol or fatty acid composition, and using appropriate parametric or nonparametric multivariate statistics, the genetic origins (olive variety) of the three fruit oil kinds were characterized. 相似文献
44.
Aiuti A Slavin S Aker M Ficara F Deola S Mortellaro A Morecki S Andolfi G Tabucchi A Carlucci F Marinello E Cattaneo F Vai S Servida P Miniero R Roncarolo MG Bordignon C 《Science (New York, N.Y.)》2002,296(5577):2410-2413
Hematopoietic stem cell (HSC) gene therapy for adenosine deaminase (ADA)-deficient severe combined immunodeficiency (SCID) has shown limited clinical efficacy because of the small proportion of engrafted genetically corrected HSCs. We describe an improved protocol for gene transfer into HSCs associated with nonmyeloablative conditioning. This protocol was used in two patients for whom enzyme replacement therapy was not available, which allowed the effect of gene therapy alone to be evaluated. Sustained engraftment of engineered HSCs with differentiation into multiple lineages resulted in increased lymphocyte counts, improved immune functions (including antigen-specific responses), and lower toxic metabolites. Both patients are currently at home and clinically well, with normal growth and development. These results indicate the safety and efficacy of HSC gene therapy combined with nonmyeloablative conditioning for the treatment of SCID. 相似文献
45.
Wing SL Harrington GJ Smith FA Bloch JI Boyer DM Freeman KH 《Science (New York, N.Y.)》2005,310(5750):993-996
Rapid global warming of 5 degrees to 10 degrees C during the Paleocene-Eocene Thermal Maximum (PETM) coincided with major turnover in vertebrate faunas, but previous studies have found little floral change. Plant fossils discovered in Wyoming, United States, show that PETM floras were a mixture of native and migrant lineages and that plant range shifts were large and rapid (occurring within 10,000 years). Floral composition and leaf shape and size suggest that climate warmed by approximately 5 degrees C during the PETM and that precipitation was low early in the event and increased later. Floral response to warming and/or increased atmospheric CO2 during the PETM was comparable in rate and magnitude to that seen in postglacial floras and to the predicted effects of anthropogenic carbon release and climate change on future vegetation. 相似文献
46.
Martrat B Grimalt JO Shackleton NJ de Abreu L Hutterli MA Stocker TF 《Science (New York, N.Y.)》2007,317(5837):502-507
Centennial climate variability over the last ice age exhibits clear bipolar behavior. High-resolution analyses of marine sediment cores from the Iberian margin trace a number of associated changes simultaneously. Proxies of sea surface temperature and water mass distribution, as well as relative biomarker content, demonstrate that this typical north-south coupling was pervasive for the cold phases of climate during the past 420,000 years. Cold episodes after relatively warm and largely ice-free periods occurred when the predominance of deep water formation changed from northern to southern sources. These results reinforce the connection between rapid climate changes at Mediterranean latitudes and century-to-millennial variability in northern and southern polar regions. 相似文献
47.
Rota A Pregel P Cannizzo FT Sereno A Appino S 《Journal of Feline Medicine and Surgery》2011,13(6):448-450
This report describes an unusual case of uterine stump pyometra in a cat whose main clinical sign at presentation was abdominal straining. At the time of ovariohysterectomy, the surgeon reported that the uterine body had a purulent content. Nearly a month after the surgery the cat showed abdominal straining. The enlarged uterine stump, filled with purulent fluid, had caused a compression of the rectum and secondary intestinal sub-occlusion. Surgical revision consisted of draining the purulent content of the remnant of the uterine body and ablating as much of it as possible; checking of the ovarian pedicles revealed the presence of a small fragment of whitish tissue on the right side, which was shown to contain, by means of histological observation and immunohistochemical staining, ovarian tissue. Four months after surgical revision the queen did not show any pathological signs and 1 year later she is still in good health. 相似文献
48.
Giuliano Pisoni Patrizia D’Amelio Francesca Sassi Giovanni Manarolla Licia Scaccabarozzi Clara Locatelli Nausicaa Mazzocchi Mirko Baruscotti Dario DiFrancesco Paolo Moroni 《Veterinary journal (London, England : 1997)》2011,189(3):361-363
Formation of multinucleated giant cells (MGCs) by macrophage fusion is a typical cytopathic effect of lentiviral replication in caprine monocytes and MGC formation from cultured caprine peripheral blood mononuclear cells (PBMCs) has been considered to be diagnostic for small ruminant lentivirus (SRLV) infection. In this study, formation of MGCs was observed after 7–14 days when PBMCs were cultured from healthy goats free from SRLV infection. These MGCs expressed tartrate-resistant acid phosphatase, calcitonin receptor, integrin αVβ3, cathepsin K and matrix metalloproteinase 9 and were able to resorb bone in vitro in the absence of RANKL and macrophage colony stimulating factor, consistent with an osteoclast phenotype. 相似文献
49.
Calucci L Capocchi A Galleschi L Ghiringhelli S Pinzino C Saviozzi F Zandomeneghi M 《Journal of agricultural and food chemistry》2004,52(13):4274-4281
Seeds of bread wheat were incubated at 40 degrees C and 100% relative humidity for 0, 3, 4, 6, and 10 days. The effects of accelerated aging on seed germinability and some biochemical properties of flour (carotenoid, free radical, and protein contents and proteolytic activity) and gluten (free radical content and flexibility) were investigated. Seed germinability decreased during aging, resulting in seed death after 10 days. A progressive decrease of carotenoid content, in particular, lutein, was observed, prolonging the incubation, whereas the free radical content increased in both flour and gluten. A degradation of soluble and storage proteins was found, associated with a marked increase of proteolytic activity and a loss of viscoelastic properties of gluten. On the contrary, puroindolines were quite resistant to the treatment. The results are discussed in comparison with those previously obtained during accelerated aging of durum wheat seeds. 相似文献
50.
Olive oil fluorescence is related to oil composition. Here it is shown that the natural clustering of different types of commercial Spanish olive oils depends on their fluorescence excitation-emission matrices (EEMs). Fifty-six commercial samples of olive oil (29 virgin olive oils, 20 pure olive oils, and 7 olive-pomace oils) were used. The clustering method was hierarchical agglomerative clustering using the Euclidean distance as a similarity measure and the average linkage. Two spectral ranges were considered (which either contained the fluorescence peak of the chlorophylls or did not), and various methods for preprocessing the fluorescence spectra were compared. The oils were clearly distinguished using the unfolded EEMs measured between lambda(ex) = 300-400 nm and lambda(em) = 400-600 nm. The optimal preprocessing was normalization of the unfolded spectra followed by column autoscaling. Also shown are the advantages of using second-order data (EEMs) instead of first-order data (a single fluorescence spectrum) for each sample. 相似文献