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71.
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
72.
Enhanced iron reduction by iron supplement: A strategy to reduce methane emission from paddies 总被引:1,自引:0,他引:1
As an option for mitigating methane emissions from rice paddies the effects of ferrihydrite application to an experimental field plot at the beginning of the growth season was studied. Methane emissions during the vegetation period of rice were significantly lower (50%) in the fertilized plot compared to the non-supplemented control plot. Although toxic effects of iron are known to occur with wetland plants including rice, our field experiment showed no deterioration of agrophysiological data. Grain yield, harvest index, and iron content of grains were not different in the two plots. Therefore, we propose that iron application is a suitable strategy to reduce methane emission from rice paddies. 相似文献
73.
74.
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
75.
76.
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
77.
C Vitu P Russo P Filippi R Vigne G Querat A Giauffret 《Comparative immunology, microbiology and infectious diseases》1982,5(4)
An indirect microELISA test was performed for detection of maedi-visna antibodies in ovine and caprine species. The antigen consisted in viral particles, highly purified by successive ultracentrifugations.By comparative testing of 934 sera in ELISA and gel immunodiffusion, we found a good correlation between these two teṡts, and moreover, ELISA revealed another 11.3% of positive samples. The precocity of this ELISA was shown by experimental infection of sheep with different strains of maedi-visna: positive sera were detected 7 weeks post-infection, instead 4–5 months with gel immunodiffusion. The complement fixation test was compared with gel immunodiffusion and was found the less sensitive.This ELISA test appeared to be satisfactory, and may be used for early diagnosis of maedi-visna infection. 相似文献
78.
79.
M E Russo 《The Cornell veterinarian》1981,71(2):221-247
Recent developments in the understanding of the cellular events in focal seizures are described. This is followed by a discussion of the pathogenesis of neuronal hyperexcitability, the mechanism of spread of the seizure discharge and the mechanisms involved in seizure termination. The pathophysiology of generalized seizures is described in terms of theories of the site of origin of the seizure discharge and possible mechanisms of the clinical phenomena associated with this discharge. 相似文献
80.
Mazzullo G Russo M Niutta PP De Vico G 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2004,33(2):102-104
BACKGROUND: Osteogenic sarcomas are rare in rabbits, but cases involving the mandible, ribs, frontal bones, and tibia have been reported. OBJECTIVE: The purpose of this study was to describe the clinical and pathologic findings in a rabbit with osteosarcoma and multiple metastases with subcutaneous involvement. METHODS: A 1-year-old female Polish rabbit was evaluated for dysorexia, lameness, gait difficulties with the hind limbs, and the presence of 2 subcutaneous nodules, on the left thigh and in the dorsal region. A hard swelling was also present at the base of the tail. Radiographic findings revealed multiple abnormalities in several bones, which were more severe in the sacrococcygeal region and femur. Several areas of calcification involving the thorax and abdomen as well as skeletal muscles, also were noted. The thigh nodule was surgically removed, and cytologic and histologic evaluations were performed. Following the rabbit's death, postmortem radiographs were taken and necropsy was performed. Samples of tissues and organs, involved bone segments, and other subcutaneous nodules were collected and examined by cytology and histology. RESULTS: Both the subcutaneous nodules and the majority of tissues and organs contained neoplastic cells whose appearance was consistent with osteogenic sarcoma. CONCLUSION: Clinical, radiologic, and pathologic data supported a diagnosis of osteosarcoma with multiple metastases and subcutaneous involvement. 相似文献