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排序方式: 共有556条查询结果,搜索用时 171 毫秒
41.
Furia E Naccarato A Sindona G Stabile G Tagarelli A 《Journal of agricultural and food chemistry》2011,59(15):8450-8457
Tropea red onion ( Allium cepa L. var. Tropea) is among the most highly appreciated Italian products. It is cultivated in specific areas of Calabria and, due to its characteristics, was recently awarded with the protected geographical indications (PGI) certification from the European Union. A reliable classification of onion samples in groups corresponding to "Tropea" and "non-Tropea" categories is now available to the producers. This important goal has been achieved through the evaluation of three supervised chemometric approaches. Onion samples with PGI brand (120) and onion samples not cultivated following the production regulations (80) were digested by a closed-vessel microwave oven system. ICP-MS equipped with a dynamic reaction cell was used to determine the concentrations of 25 elements (Al, Ba, Ca, Cd, Ce, Cr, Dy, Eu, Fe, Ga, Gd, Ho, La, Mg, Mn, Na, Nd, Ni, Pr, Rb, Sm, Sr, Tl, Y, and Zn). The multielement fingerprint was processed using linear discriminant analysis (LDA) (standard and stepwise), soft independent modeling of class analogy (SIMCA), and back-propagation artificial neural network (BP-ANN). The cross-validation procedure has shown good results in terms of the prediction ability for all of the chemometric models: standard LDA, 94.0%; stepwise LDA, 94.5%; SIMCA, 95.5%; and BP-ANN, 91.5%. 相似文献
42.
Giorgi M Cuniberti B Ye G Barbero R Sgorbini M Vercelli C Corazza M Re G 《Veterinary journal (London, England : 1997)》2011,190(1):143-149
Tepoxalin is a non-steroidal anti-inflammatory drug with analgesic, anti-inflammatory, and antipyretic properties and has been recently introduced into veterinary medicine. The aim of this study was to evaluate the pharmacokinetic/pharmacodynamic (PK/PD) profile of tepoxalin to assess whether it would be suitable for clinical use in horses. Six female fasting/fed horses were given 10mg/kg tepoxalin orally in a cross-over study. After administration, tepoxalin underwent rapid and extensive hydrolytic conversion to its carboxylic acid metabolite RWJ-20142. In animals that had been fed, the plasma concentrations of tepoxalin were undetectable, whereas in fasting animals they were close to the limit of quantification of the method. No differences between the fasting/fed groups in RWJ-20142 plasma concentrations were shown. Tepoxalin showed a strong and long-lasting ex vivo inhibitory activity against cyclooxygenase (COX)-1, mainly due to its main metabolite RWJ-20142. Tepoxalin and RWJ-20142 do not seem to possess either COX-2 or 5-lipoxygenase inhibitory activity in the horse. These features suggest that the drug is a selective COX-1 inhibitor in horses, with no significant anti-inflammatory activity. Thus, its long term use in equine practice could be of concern. 相似文献
43.
Giuseppe PICCIONE Francesco FAZIO Stefania CASELLA Pietro PENNISI Giovanni CAOLA 《Animal Science Journal》2011,82(3):481-485
The aim of the present study was to evaluate the effect of shearing on physiological and oxidative stress parameters in ewes. Twenty Comisana ewes were used and divided into two groups. Ten ewes were left unshorn as a control group (Group A) and 10 ewes were shorn (Group B). All measurements were taken before and after shearing, and repeated 8 h after shearing and 1, 2, 3, 4, 5, 10 and 15 days after shearing. Reactive oxygen species (dROMs), antioxidant barrier (oxy‐adsorbent), thiol antioxidant barrier (SHp) and packed cell volume (PCV) were assessed in blood samples collected by means of jugular venipuncture. Rectal temperature (RT), respiratory rate (RR) and heart rate (HR) were also measured. Two‐way repeated measures analysis of variance (ANOVA), followed by Bonferroni's test, was used for the assessment of significant effects due to shearing and time. The statistical analysis showed significant increases (P < 0.01) of dROMs, oxy‐adsorbent, SHp, and a significant decrease (P < 0.01) of RT and RR associated with time and shearing. Our results indicate that shearing causes a change in the ewe's homeostatic balance that leads to oxidative stress. 相似文献
44.
Lanteri G Sfacteria A Macri D Reale S Marino F 《Journal of zoo and wildlife medicine》2011,42(2):309-312
Penicillium mycosis, or penicilliosis, is rare in animals. This report describes the clinical signs and pathological, immunohistochemical, and biomolecular findings in a case of avian penicilliosis in a Congo African grey parrot. On gross necropsy, pyogranulomatous changes were identified in the lung, liver, and kidney. Histopathology demonstrated periodic acid Schiff-(PAS) and Grocott-positive hyphae in these tissues. Immunohistochemistry confirmed the genus of the fungus and polymerase chain reaction (PCR) confirmed a high homology with Penicillium chrysogenum. 相似文献
45.
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
46.
Benincasa C De Nino A Lombardo N Perri E Sindona G Tagarelli A 《Journal of agricultural and food chemistry》2003,51(3):733-741
An SPME-GC/ion trap method was exploited to determine the chromatogram of volatile compounds of organic olive oils of southern Italian regions. The method is based on the assay of the terminal species of the "lipoxygenase pathway", which are present in the volatile fraction of the sampled compounds. Ethyl isobutanoate was used as internal standard in either the EI or CI ionization mode. The absolute concentration values of each analyte were evaluated through good-to-excellent calibration curves. Case studies on oils obtained from different cultivars or harvesting times are presented. The quantitative data for each compound were subjected to principal component analysis to characterize the different cultivars of this work. 相似文献
47.
Cabras P Farris GA Pinna MV Pusino A 《Journal of agricultural and food chemistry》2004,52(26):8053-8056
The fungicide fenhexamid [N-(2,3-dichloro-4-hydroxyphenyl)-1-methylcyclohexanecarboxamide] degraded rapidly by UV or sunlight irradiation, yielding 7-chloro-6-hydroxy-2-(1-methylcyclohexyl)-1,3-benzoxazole (CHB) as a main photoproduct. CHB was isolated, and its effect on alcoholic fermentation of Saccharomyces cerevisiae was studied. The results indicate that the presence of CHB does not affect the extent of alcohol production. After 12 days, the amount of CHB in the fermentation medium decreased by ca. 65%. Only 25% of the missing CHB was recovered unchanged from yeasts, most likely because it was adsorbed on the yeast wall cell. The remaining part degraded during the fermentation process. Glucan and chitin, two potential adsorbents, which constitute yeast cell walls, exhibited affinity for CHB. 相似文献
48.
49.
Characterization of the anthocyanin fraction of sicilian blood orange juice by micro-HPLC-ESI/MS 总被引:5,自引:0,他引:5
Dugo P Mondello L Morabito D Dugo G 《Journal of agricultural and food chemistry》2003,51(5):1173-1176
Anthocyanins of red orange juices were analyzed by micro-HPLC coupled on-line with an MS detector equipped with an ESI source. The use of microcolumn HPLC greatly enhanced detection performance, allowing direct identification of the anthocyanins present in the orange juices. The use of a soft ionization technique allows detection of the molecular ions of the aglycons. Eight components were identified, five of them for the first time in red orange juice. Three additional anthocyanins were detected, of which only the aglycon was identified. 相似文献
50.
Pier Giovanni Garoglio 《Plant foods for human nutrition (Dordrecht, Netherlands)》1964,11(2-4):169-193
Resumé La chromatographie en phase gazeuse étant à la fois une méthode qualitative et quantitative, constitue une méthode idéale destinée à résoudre la complexité des analyses des additifs alimentaires. Après une énumération des perfectionnements récents apportés à ces appareils, l'auteur fait un exposé de l'application et des résultats, notamment dans les domaines: Huile d'olive, Beurre, Saindoux, Vin, Cacao, Chocolat. Identification des acides gras, table des constituants, recherches de falsifications, analyse des substances étrangères, altération des vins, discussion des résultats d'analyse.Pour le dosage des résidus de pesticides et pour la recherche des agents antifermentaires, la chromatographie en phase gazeuse s'avère d'une grande utilité en raison de sa précision et sa rapidité.Comme un complément de la chromatographie en phase gazeuse l'auteur insiste sur l'importance, dans le secteur alimentaire, d'une nouvelle méthode d'analyse, basée sur des réactions enzymatiques et sur les études exécutées par son Institut pour la mise ou point de telles méthodes enzymatiques: détermination du glucose, du fructose, du saccharose dans les moûts et les vins, etc...
Summary Gas-chromatography being a qualitative and quantitative method at the same time, makes an ideal method enabling us to solve the complexity of the analyses of food additives. After enumerating the recent improvements in the gas-chromatography equipment the author explains its applications and shows the results obtained, more specially in the following fields: olive oil, butter, lard, wine, cocoa, chocolate, identification of fatty acids, table of components, search for adulterants, analysis of foreign substances, deterioration of wines, discussion of the results of analyses.In the determination of pesticide residues, and the search for antiferments, gas-chromatography appears to be extremely useful, thanks to its precision and rapidity.As a supplement to gas-chromatography the author insists on the importance, in this field of foods, of a new analytical method based on enzymatic reactions, and on the investigations, carried on in this Institute, aimed to set up such enzymatic methods, to be used in the study of glucose, fructose, and saccharose deteriorations in musts and wines, etc...
Zusammenfassung Die Gaschromatographie ist gleichzeitig eine quantitative und qualitative Analysenmethode. Sie ist daher hervorragend für die Lösung der komplexen Probleme auf dem Gebiete der Lebensmittel-Zusatzstoffe geeignet. Nach Aufzählung der letzten Verbesserungen in der Apparatetechnik, werden Anwendungsmöglichkeiten und Ergebnisse besprochen, insbesondere für Analysen von Olivenöl, Butter, Schmalz, Wein, Kakao und Schokolade. Bestimmung der Fettsäuren, Liste der Bestandteile, Nachweis von Fälschungen, Fremdstoffanalysen, Weinalterung, kritische Betrachtung der Ergebnisse.Für den Nachweis der Pestizid-Rückstände und die Bestimmung von Antifermenten, leistet die Gaschromatographie infolge der Genauigkeit und Schnelligkeit der Methode bereits große Dienste.Zur Ergänzung der gaschromatographischen Verfahren schlägt der Autor, insbesondere für Lebensmittelanalysen ein auf enzymatischen Reaktionen fußendes neues Verfahren vor. Hierzu sind die Untersuchungen in seinem Institut weit fortgeschritten, insbesondere für die Bestimmung von Glukose, Fruktose, Saccharose in Most und Wein.相似文献