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51.
Gancel AL Ollitrault P Froelicher Y Tomi F Jacquemond C Luro F Brillouet JM 《Journal of agricultural and food chemistry》2005,53(6):2224-2230
Volatile compounds were extracted by a pentane/ether (1:1) mixture from the leaves of six citrus somatic allotetraploid hybrids resulting from various combinations of lime, lemon, citron, sweet orange, and grapefruit. Extracts were examined by gas chromatography-mass spectrometry (GC-MS) and compared with those of their respective parents. All hybrids having an acid citrus parent exhibit the same relative contents in hydrocarbons and oxygenated compounds as the acid citrus, while the (grapefruit + orange) hybrid behaves similarly to its two parents. When volatile compound contents (microg g(-1)) are examined in detail, several behaviors are encountered in hybrids and seem to depend on the presence/absence of the considered parental compound and on the corresponding hybrid combination. Meanwhile, the sesquiterpene hydrocarbons are present in all hybrids at concentrations systematically lower than those of the highest parental producers. Statistical analyses show that hybrids exhibit hardly discriminable aromatic profiles, meaning that no strong dominance of one or the other parent was observed in hybrids with regards to the leaf volatile compound production. 相似文献
52.
C. Francois C. Feller G. Guiraud J. Loury J. -P. Boudot 《Biology and Fertility of Soils》1991,12(3):182-188
Summary The fate of N when incorporated in a ferrallitic soil was investigated during a 3-month incubation, using either 15N-labelled urea or 15N-labelled crop residues (sugarcane roots and leaves). The organic matter was characterized by particle-size fractionation. The urea-derived organic 15N was mainly found in the clay-sized fractions and was ascribed to biological activity. The plant-derived 15N was observed both in the sand-sized and in the clay-sized fractions; the former pool was ascribed to the persistence of crops residues, the latter to biological immobilization. The relative proportions of organic 15N recovered in the various clay fractions (coarse, fine, and very fine) were similar, irrespective of the nature of the added 15N. The very fine clay fraction (F<0.05 m) showed the highest isotopic excess, and thus gave rise to the highest turnover rate. 相似文献
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55.
Chetboul V Lefebvre HP Sampedrano CC Gouni V Saponaro V Serres F Concordet D Nicolle AP Pouchelon JL 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(4):742-753
BACKGROUND: Pimobendan (PIMO) is an inodilator that may have some beneficial effects in canine degenerative mitral valve disease (MVD). However, little information is available about its cardiac effects in dogs without systolic myocardial dysfunction. HYPOTHESIS: Compared to benazepril (BNZ), an angiotensin-converting enzyme inhibitor, PIMO may worsen valve regurgitation in early canine MVD. ANIMALS: Twelve Beagles with asymptomatic MVD were randomized into 2 groups (n = 6) receiving BNZ or PIMO at dosages of 0.25 mg/kg PO q24h and q12h respectively, for 512 days. METHODS: The study followed a blinded, randomized, prospective, and parallel group design. After day 512, the dogs were necropsied, and cardiac histopathology was performed in a blinded manner. RESULTS: A significant treatment effect was observed as soon as day 15 with increased systolic function in the PIMO group by comparison to baseline value as assessed by fractional shortening (P < .0001) and tissue Doppler variables (P = .001). Concurrently, the maximum area and peak velocity of the regurgitant jet signal increased (P < .001), whereas these variables remained stable in the BNZ group. Histologic grades of mitral valve lesions were more severe in the PIMO group than in the BNZ group. Moreover, acute focal hemorrhages, endothelial papillary hyperplasia, and infiltration of chordae tendinae with glycosaminoglycans were observed in the mitral valves of dogs from the PIMO group but not in those of the BNZ group. CONCLUSIONS AND CLINICAL IMPORTANCE: PIMO has adverse cardiac functional and morphologic effects in dogs with asymptomatic MVD. Additional investigation in dogs with symptomatic MVD is now warranted. 相似文献
56.
Carpintero R Alonso C Piñeiro M Iturralde M Andrés M Le Potier MF Madec F Alava MA Piñeiro A Lampreave F 《Veterinary research》2007,38(5):741-753
In the present work, we studied the acute phase protein response after experimental virus infection in pigs. The animals were experimentally infected with African Swine Fever (ASF) or Aujeszky's disease (AD) viruses. The clinical course of ASF infection correlated with increasingly high levels of pig Major Acute-phase Protein (pig-MAP) (mean value of 6 mg/mL on day 6 post infection (p.i.), from 6 to 9 times higher than day 0) and sharp apolipoprotein A-I (apo A-I) decrease (mean value of 0.5 mg/mL, from 4 to 10 times lower than day 0 on day 4 p.i.). AD-clinical signs appeared at day 3 p.i., both in vaccinated (moderate clinical signs) and non-vaccinated pigs (severe outcome within 48 h p.i.). Pig-MAP and apo A-I profiles also followed clinical signs (changing from 0.70 mg/mL to around 3 mg/mL and from around 3 mg/mL to 0.96 mg/mL, respectively in non-vaccinated animals), with minor changes in concentration in the vaccinated group. Haptoglobin levels significantly increased in ASF and AD infected animals (mean maximum values of 2.77 and 3.96 mg/mL, respectively). Minor differences for the C-Reactive Protein in the case of ASF were observed, whereas its concentration increased more than 7 times in AD-infection. The albumin level was not modified in either case. The correlation of clinical signs to our data suggests the potential use of pig-MAP and apo A-I in monitoring infections in swine. 相似文献
57.
Hongsibsong S Wipasa J Pattarawarapan M Chantara S Stuetz W Nosten F Prapamontol T 《Journal of agricultural and food chemistry》2012,60(1):16-22
1,1-Dichloro-2,2-bis(p-chlorophenyl) ethylene (p,p'-DDE) is the major metabolite of insecticide 2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane (p,p'-DDT) and a persistent organic pollutant (POPs) with concerns regarding its bioaccumulation and persistence in the environment and food chain. In the present study, an indirect competitive enzyme-linked immunosorbant assay (ic-ELISA) specific for the detection of p,p'-DDE is described. In hapten synthesis, 2,2'-bis(4-chlorophenyl)ethanol and glutaric anhydride were used as precursor and spacer arm, respectively. The hapten was then conjugated to bovine serum albumin (BSA) as immunogen for mouse immunization and also conjugated to ovalbumin as coating antigen for ELISA. The developed ic-ELISA was used for detecting p,p'-DDE in human milk samples and validated against the results from conventional gas chromatography-electron capture detection (GC-ECD). Coefficients of variation (%CV) of ELISA were 5.7-10.4% for intra-assay and 10.6-19.6% for interassay variations. The Pearson correlation coefficient of p,p'-DDE concentrations between ic-ELISA and GC-ECD was r = 0.766, which was in an acceptable range. The results indicate that the developed assay could be an alternative analytical tool for monitoring p,p'-DDE in lipimic matrices such as human milk. 相似文献
58.
Fanciullino AL Dhuique-Mayer C Luro F Casanova J Morillon R Ollitrault P 《Journal of agricultural and food chemistry》2006,54(12):4397-4406
Citrus fruits are complex sources of carotenoids with more than 100 kinds of pigments reported in this genus. To understand the origin of the diversity of carotenoid compositions of citrus fruit, 25 genotypes that belong to the 8 cultivated Citrus species were analyzed. Juice extracts of mature fruit were analyzed by high-performance liquid chromatography using a C30 column. The 25 citrus genotypes presented different carotenoid profiles with 25 distinct compounds isolated. Statistical analyses revealed a strong impact of genotype on carotenoid compositions. Two kinds of classifications of genotypes were performed: on qualitative data and on quantitative data, respectively. The results showed that variability in carotenoid compositions was more interspecific than intraspecific. Two carotenoids, cis-violaxanthin and the beta-cryptoxanthin, strongly determined the classification on qualitative data, which was also in agreement with previous citrus variety classifications. These findings provide evidence that, as for other phenotypical traits, the general evolution of cultivated Citrus is the main factor of the organization of carotenoid diversity among citrus varieties. To the authors' knowledge this is the first study that links the diversity of carotenoid composition to the citrus genetic diversity. These results lead to the proposed major biosynthetic steps involved in the differential carotenoid accumulation. Possible regulation mechanisms are also discussed. 相似文献
59.
Luna Gutiérrez-Cepeda álvaro Fernández Francisco Crespo Miguel ángel Ramírez Jaime Gosálvez Consuelo Serres 《Acta veterinaria Scandinavica》2012,54(1):72
Background
Variability among stallions in terms of semen cryopreservation quality renders it difficult to arrive at a standardized cryopreservation method. Different extenders and processing techniques (such us colloidal centrifugation) are used in order to optimize post-thaw sperm quality. Sperm chromatin integrity analysis is an effective tool for assessing such quality. The aim of the present study was to compare the effect of two single layer colloidal centrifugation protocols (prior to cryopreservation) in combination with three commercial freezing extenders on the post-thaw chromatin integrity of equine sperm samples at different post-thaw incubation (37°C) times (i.e., their DNA fragmentation dynamics).Results
Post-thaw DNA fragmentation levels in semen samples subjected to either of the colloidal centrifugation protocols were significantly lower (p<0.05) immediately after thawing and after 4 h of incubation at 37°C compared to samples that underwent standard (control) centrifugation. The use of InraFreeze® extender was associated with significantly less DNA fragmentation than the use of Botu-Crio® extender at 6 h of incubation, and than the use of either Botu-Crio® or Gent® extender at 24 h of incubation (p<0.05).Conclusions
These results suggest that single layer colloidal centrifugation performed with extended or raw semen prior to cryopreservation reduces DNA fragmentation during the first four hours after thawing. Further studies are needed to determine the influence of freezing extenders on equine sperm DNA fragmentation dynamics. 相似文献60.
Francois Beaudeau Camilla Bj?rkman Stefan Alenius Jenny Fr?ssling 《Acta veterinaria Scandinavica》2010,52(1):33