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31.
Alfonso Ranalli Donato Marchegiani Stefania Contento Fabio Girardi Maria Paola Nicolosi Marco Desiderio Brullo 《European Journal of Lipid Science and Technology》2009,111(7):678-687
This research paper reports on the concentrations of oleuropein in fruits of seven Italian olive cultivars. These oleuropein levels, during fruit growth and maturation, were monitored by taking olive samples from the same olive trees grown in Middle Italy. A novel high‐resolution gas chromatography (HRGC) oleuropein quantification method and a new high‐performance liquid chromatography (HPLC) method were developed. The olive fruits showed high contents of oleuropein, which were greatly influenced by the olive cultivar (genetic store) factor. The stage of fruit growth and maturation was another factor strongly affecting the contents of iridoid oleuropein in olive drupes, whatever the olive cultivar considered. Green olives had much higher concentrations of this biofunctional glucoside, which decreased regularly during fruit growth and ripeness. No differences were observed between the two developed oleuropein quantification methods, which gave, for all the olive cultivars, average values of fruit oleuropein contents that were not statistically different. These two reliable repetitive methods, noticeably the HPLC one (which also showed a lower running time), could be used for routine determination of oleuropein in olive drupes. We observed that, in general, olive cultivars having high oleuropein concentrations in the fruits were also characterized by marked oleuropein contents in the leaves. 相似文献
32.
Ricardo K. Donato Moisés A. Benvegnú Luciano G. Furlan Raquel S. Mauler Henri S. Schrekker 《应用聚合物科学杂志》2010,116(1):304-307
This article describes the application of ionic liquid 1‐decyl‐3‐methylimidazolium tetrafluoroborate in the preparation of polypropylene‐silica composites. The sol‐gel technology was used to prepare xerogel silica‐ionic liquid hybrid S1 , which was obtained as a free flowing powder of aggregated spherical particles. Ionic liquid free silica S2 was obtained by extraction and calcination of S1 . Melt blending of isotactic polypropylene with S1 and S2 afforded the composites C1 (with ionic liquid) and C2 (without ionic liquid), respectively. The presence of ionic liquid on the S1 silica surface promoted significantly improved silica dispersion in the polymer matrix and prevented compression of the silica particles. Furthermore, the crystallization temperature of composite C1 was significantly higher, which indicated that silica‐ionic liquid filler S1 acted as nucleating agent. The resistance to thermal decomposition of both composites was increased, but this was higher in the presence of ionic liquid. These results show that liquid salts can function as coupling agents and compatibalizers for the preparation of polymeric composites with differentiated properties. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
33.
Y Ji DM Stelly M De Donato MM Goodman CG Williams 《Canadian Metallurgical Quarterly》1999,151(2):821-830
Maize meiotic mutant desynaptic (dy) was tested as a candidate recombination modifier gene because its effect is manifested in prophase I. Recombination rates for desynaptic (dy) and its wild type were compared in two ways: (1) segregation analysis using six linked molecular markers on chromosome 1L and (2) cytogenetic analysis using fluorescence in situ hybridization (FISH)-aided meiotic configurations observed in metaphase I. Chromosome 1L map lengths among the six linked markers were 45-63 cM for five F2 dy/dy plants, significantly lower than the wild-type F2 map distance of 72 cM. Chromosomes 2 and 6 were marked with rDNA FISH probes, and their map lengths were estimated from FISH-adorned meiotic configurations using the expectation-maximization algorithm. Chiasma frequencies for dy/dy plants were significantly reduced for both arms of chromosome 2, for chromosome arm 6L, and for eight unidentified chromosomes. There was a notable exception for the nucleolus-organizing region-bearing arm chromosome arm 6S, where dy increased chiasma frequency. Maize meiotic mutant desynaptic is a recombination modifier gene based on cytogenetic and segregation analyses. 相似文献
34.
Maria Pieralice Lucrezia Sergio Donato Di Venere Pavel Venediktov 《European Food Research and Technology》2011,232(5):919-923
The quality of leafy vegetables has to be guaranteed for consumers over the whole postharvest period, usually limited to 5–7 days.
The analyses to evaluate the quality of vegetables are very time- and resource consuming, so the use of qualitative markers
can be much useful. The aim of this work was to evaluate the use of thermoluminescence (TL) parameters as qualitative markers
of fresh-cut leafy vegetables during the shelf life. TL is a technique consisting of a cooling, followed by the progressive
warming, of a preilluminated sample to reveal the different types of charge pairs as successive emission bands, which are
resolved better than the corresponding decay phases recorded at constant temperature. Experiments were performed on rocket
(Diplotaxis tenuifolia L.) stored at 2 °C for 7 days. During storage, several changes in TL glow curves were found. The position of the peaks showed
a shift to higher temperature. The area of the peaks, relating to the photosystem II (20–65 °C), grew up lightly; whereas
in the temperature range that detects lipidic peroxidation (65–140 °C), the TL emission became more than twice. These changes
demonstrated that, during the shelf life, a progressive destabilization of PSII centres occurred and that lipid peroxidation
products were accumulated in membranes. TL could be used to estimate the damages immediately after as well as during the storage
period. This is the first time that TL was used to evaluate the quality of fresh-cut vegetables products during the shelf
life. 相似文献
35.
R Scala I Archinucci M Naldi S Donato Alessi F Fabianelli G Coniglio G Guadagni M Rossi 《Canadian Metallurgical Quarterly》1997,63(7-8):245-248
Noninvasive positive pressure ventilation (NPPV) via nasal mask is well known to be effective in the treatment of acute respiratory failure (ARF) secondary to chronic obstructive pulmonary disease (COPD). A case of ARF with hypercapnic coma due to exacerbation of COPD is described. Six hours of conservative therapy with oxygen and medical treatment did not show any result. As endotracheal intubation (ET) was avoided on the basis of advanced age, poor life expectancy of the patient and family wish, NPPV was set up using a pressure triggered ventilator. After 61 hours of uninterrupted NPPV, the acid-base alteration and the lethargic status was fully reversed. The conclusions is drawn that NPPV may be useful also in the treatment of patients affected by severe decompensated hypercapnic respiratory failure in whom ET is not indicated. 相似文献
36.
F Ficuccilli M Iacobini MR Beglieri P Papoff M Mancuso A Caradonna AI Donato P Colarizi 《Canadian Metallurgical Quarterly》1997,49(12):571-577
Purpura fulminans is a rare form of disseminated intravascular coagulation characterized by rapidly progressive purpuric lesions, hypotension and, in some cases, fever. In neonates, purpura fulminans usually develops following deficiency of anticoagulant protein C or S, although acquired forms have been described. The management of disseminated intravascular coagulation is still controversial, with some studies finding a positive effect of anticoagulants and others showing no effect or even a detrimental one. Therefore, at present, management is limited to the treatment of underlying disease and replacement of clotting factors. Personal experience is reported on the efficacy of heparin in combination with antithrombin III in the treatment of purpura fulminans in two preterm neonates who did not have inherited deficiency of protein C or S and developed the disease possibly following prolonged labor (36 hours) in the first case, and maternal neoplasia, in the second. Both neonates presented with widespread cyanotic areas rapidly evolving in purpuric lesions and hemorrhagic bullae. Laboratory tests (prolonged prothrombin and partial thromboplastin time, fibrinogen and antithrombin III concentrations below normal ranges, d-dimer highly positive) were consistent with disseminated intravascular coagulation. In both cases anticoagulant treatment with heparin (50 UI/kg in bolus followed by 15 UI/kg/h) and antithrombin III was associated with resolution of disseminated intravascular coagulation and prompt amelioration of the purpuric lesions, without apparent side effects. 相似文献
37.
38.
Gustavo H. B. Donato Rodrigo Magnabosco Claudio Ruggieri 《International Journal of Fracture》1991,49(4):I-ii
Contents of volume 49 (1991) 相似文献
39.
Data from the Brazilian Agricultural Ministry show that before the implementation of the Brazilian programme of nitrofuran control in February 2003, the cases of contamination of Brazilian chicken by nitrofurans were almost exclusively due to furaltadone. After May 2003, such cases decreased until no more reports of Brazilian chicken contamination with this nitrofuran were reported. Curiously, after April 2003, an increase was observed in the numbers of contaminated samples by semicarbazide, the target metabolite of nitrofurazone. Most Brazilian chicken found to be contaminated with semicarbazide has been covered with flour, salt and spices. For this reason, the authors' laboratory initialized a programme for tracing possible sources of food contamination by semicarbazide. After several semicarbazide positives in flour of controlled origin (results varying between 2.2 and 5.2 microg kg(-1)), the different additives used in the cereal industry as flour improvement agents were studied. The results indicate that the compound azodicarbonamide was responsible for the source of the contaminant semicarbazide. 相似文献
40.