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71.
Hydrophilic phenols are the most abundant natural antioxidants of virgin olive oil (VOO), in which tocopherols and carotenes are also present. The prevalent classes of hydrophilic phenols found in VOO are phenyl alcohols, phenolic acids, secoiridoids such as the dialdehydic form of decarboxymethyl elenolic acid linked to (3,4-dihydroxyphenyl)ethanol or (p-hydroxypheny1)ethanol (3,4-DHPEA-EDA or p-HPEA-EDA) and an isomer of the oleuropein aglycon (3,4-DHPEA-EA), lignans such as (+)-1-acetoxypinoresinol and (+)-pinoresinol, and flavonoids. A new method for the analysis of VOO hydrophilic phenols by direct injection in high-performance liquid chromatography (HPLC) with the use of a fluorescence detector (FLD) has been proposed and compared with the traditional liquid-liquid extraction technique followed by the HPLC analysis utilizing a diode array detector (DAD) and a FLD. Results show that the most important classes of phenolic compounds occurring in VOO can be evaluated using HPLC direct injection. The efficiency of the new method, as compared to the liquid-liquid extraction, was higher to quantify phenyl alcohols, lignans, and 3,4-DHPEA-EA and lower for the evaluation of 3,4-DHPEA-EDA and p-HPEA-EDA.  相似文献   
72.
The capacity of alquitara (a traditional distillation system) to produce cider brandies is evaluated. To do so, the chemical composition of 12 fractions obtained during the distillation process and the cider brandies obtained from five ciders were analyzed (alcohol strength, methanol, volatile substances, furfural, and metals), taking into account European and Spanish legislation. During the course of distillation, an important increase in methanol, furfural, 2-phenylethanol, and metals in the last fractions was observed, while fusel oils were more abundant in the first fractions collected. Only acetaldehyde behaved differently, showing a minimum concentration in the middle fractions that might be explained by its formation on the surface of alquitara. On the other hand, the final distillates obtained by means of this method complied with the considered regulations. Worth highlighting in this regard are the low levels of a potential toxin such as methanol, as well as the detection of a constant ratio for methanol, ethanol, and fusel oil for the pairs of cider/spirits analyzed, which could be interpreted as an indication of good uniformity in the distillation system and method, thus guaranteeing product quality.  相似文献   
73.
Nutritionists recommend increasing the intake of soluble dietary fiber (SDF), which is very low in most cereal-based products. Conversion of insoluble DF (IDF) into SDF can be achieved by chemical treatments, but this affects the sensorial properties of the products. In this study, the possibility of getting a substantial increase of SDF from cereal products using a tailored preparation of Trichoderma enzymes is reported. Enzymes were produced cultivating Trichoderma using durum wheat fiber (DWF) and barley spent grain (BSG) as unique carbon sources. Many Trichoderma strains were screened, and the hydrolysis conditions able to increase by enzymatic treatment the amount of SDF in DWF and BSG were determined. Results demonstrate in both products that it is possible to triple the amount of SDF without a marked decrease of total DF. The enzymatic treatment also causes the release of hydroxycinnamic acids, mainly ferulic acid, that are linked to the polysaccharides chains. This increases the free phenolic concentration, the water-soluble antioxidant activity, and, in turn, the phenol compounds bioavailability.  相似文献   
74.
75.
OBJECTIVE: To analyze the morphology, cytoarchitecture, and lumbosacral spinal cord projections of the red nucleus (RN) in cattle. ANIMALS: 8 healthy Friesian male calves. PROCEDURES: Anesthetized calves underwent a dorsal laminectomy at L5. Eight bilateral injections (lateral to the midline) of the neuronal retrograde fluorescent tracer fast blue (FB) were administered into the exposed lumbosacral portion of the spinal cord. A postsurgical calf survival time of 38 to 55 days was used. Following euthanasia, the midbrain and the L5-S2 spinal cord segments were removed. Nissl's method of staining was applied on paraffin-embedded and frozen sections of the midbrain. RESULTS: The mean length of the RN from the caudal to cranial end ranged from 6,680 to 8,640 microm. The magnocellular and parvicellular components of the RN were intermixed throughout the nucleus, but the former predominate at the caudal portion of the nucleus and the latter at the cranial portion with a gradual transitional zone. The FB-labeled neurons were found along the entire craniocaudal extension of the nucleus, mainly in its ventrolateral part. The number of FB-labeled neurons was determined in 4 calves, ranging from 191 to 1,469 (mean, 465). The mean cross-sectional area of the FB-labeled neurons was approximately 1,680 microm2. CONCLUSIONS AND CLINICAL RELEVANCE: In cattle, small, medium, and large RN neurons, located along the entire craniocaudal extension of the RN, contribute to the rubrospinal tract reaching the L6-S1 spinal cord segments. Thus, in cattle, as has been shown in cats, the RN parvicellular population also projects to the spinal cord.  相似文献   
76.
Common bacterial blight (CBB) caused by Xanthomonas axonopodis pv. phaseoli (Xap) is the main bacterial disease of snap bean. The present work aimed to select snap bean genotypes that are resistant to CBB based on three components of resistance: area under the disease progress curve, latent period, and lesion diameter on pods (DL). A completely randomized two-factor factorial design with six replications was used to evaluate leaves and pods of 14 snap bean and three common bean genotypes (PI 207262, BAC-6 and A-794) with high resistance to CBB. Two Xap isolates, 1394-98 and 775-90, were used to inoculate leaves and pods. Data were analyzed using nonparametric statistics. Significant differences were observed among the evaluated genotypes for all of the components of resistance, except for DL. The snap bean UENF 1482 demonstrated good performance in two disease resistance components. For this reason, this genotype can be recommended for use in breeding programs that aim to generate snap bean genotypes resistant to Xanthomonas axonopodis pv. phaseoli.  相似文献   
77.
Potato bacterial wilt, caused by the bacterium Ralstonia solanacearum race 3 biovar 2 (R3bv2), affects potato production in several regions in the world. The disease becomes visually detectable when extensive damage to the crop has already occurred. Two greenhouse experiments were conducted to test the capability of a remote sensing diagnostic method supported by multispectral and multifractal analyses of the light reflectance signal, to detect physiological and morphological changes in plants caused by the infection. The analysis was carried out using the Wavelet Transform Modulus Maxima (WTMM) combined with the Multifractal (MF) analysis to assess the variability of high-resolution temporal and spatial signals and the conservative properties of the processes across temporal and spatial scales. The multispectral signal, enhanced by multifractal analysis, detected both symptomatic and latently infected plants, matching the results of ELISA laboratory assessment in 100 and 82%, respectively. Although the multispectral method provided no earlier detection than the visual assessment on symptomatic plants, the former was able to detect asymptomatic latent infection, showing a great potential as a monitoring tool for the control of bacterial wilt in potato crops. Applied to precision agriculture, this capability of the remote sensing diagnostic methodology would provide a more efficient control of the disease through an early and full spatial assessment of the health status of the crop and the prevention of spreading the disease.  相似文献   
78.
79.
This paper reports a survey conducted in France during 2011 to evaluate the efficacy of commonly used anthelmintics against horse cyathostomins. A total of 40 farms and 1089 horses were screened for the presence of cyathostomins. All farms but one were positive, with an overall animal infection rate of 53.7%, ranging from 9% to 83% on individual farms. On 445 horses from 30 of these farms, a faecal egg count reduction test (FECRT) was performed to evaluate the efficacy of oral formulations of fenbendazole (FBZ), pyrantel embonate (PYR), ivermectin (IVM) and moxidectin (MOX). Calculation of the mean FECR and 95% confidence intervals (95% CI) around the mean was performed using bootstrap analysis. Resistance to FBZ was found on 17 of 18 farms investigated, with a mean reduction of 57% (95% CI: 38.5-71.2%). Suspected resistance for PYR was found on 6 of 30 farms, and confirmed on another 3 of 30 farms, with a mean reduction for PYR of 94.7% (95% CI: 88.9-98.5%). Reduced efficacy simultaneously of FBZ and PYR was found in 7 farms. Reduced efficacy of IVM was found in one animal on one farm and of MOX in one animal on another farm, and was combined with resistance against FBZ and/or PYR. These results indicate that single and multiple drug resistance and reduced efficacy in equine cyathostomins is present in France. Macrocylic lactones proved to be highly effective compounds against cyathostomins, with reduced efficacy for IVM and MOX in two farms only. These results extend present knowledge on the occurrence of drug resistant cyathostomins in Europe, and illustrate the necessity to use anthelmintics in appropriate worm control programmes.  相似文献   
80.
Electrocardiographic tracings of an English Bulldog referred for cardiogenic shock due to an orthodromic atrioventricular reciprocating tachycardia conducted with intraventricular conduction disturbance and mimicking ventricular tachycardia (VT) are presented. At admission the surface ECG showed a wide QRS complex tachycardia (WCT) that was converted to sinus rhythm using manual cardioversion (chest thump). This change revealed pre-existing right bundle branch block, and a final diagnosis of supraventricular tachycardia (SVT) with intraventricular conduction disturbance was made. Electrophysiologic study defined the SVT mechanism as an atrioventricular macroreentrant tachycardia mediated by a single mid-septal accessory pathway. The differentiation between various types of WCT is essential when antiarrhythmic therapy is considered. The surface ECG should be systematically evaluated in order to recognize the characteristic features of SVT and VT. Moreover chest thump procedure can be very helpful in the attempt to convert the rhythm to sinus rhythm and to correctly recognize the underlying arrhythmia.  相似文献   
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