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71.
Two monovarietal extra virgin olive oils from Arbequina and Picual cultivars were subjected to heating at 180 degrees C for 36 h. Oxidation progress was monitored by measuring oil quality changes (peroxide value and conjugated dienes and trienes), fatty acid composition, and minor compound content. Tocopherols and polyphenols were the most affected by the thermal treatment and showed the highest degradation rate although their behavior was different for each cultivar. Alpha-tocopherol loss was more important in Arbequina oil whereas, total phenol content loss was greater in Picual oil. The later showed an important decrease in hydroxytyrosol (3,4-DHPEA) and its secoiridoid derivatives (3,4-DHPEA-EDA and 3,4-DHPEA-EA), while lignans decrease was lesser. For Arbequina oil these compounds remained stable, and a lowering tendency was observed for tyrosol (p-HPEA) and its derivatives (p-HPEA-EDA and p-HPEA-EA). In general, flavone content showed a decrease during heating, being higher for Arbequina oil. On the other hand, oleic acid, sterols, squalene, and triterpenic alcohols (erythrodiol and uvaol) and acids (oleanolic and maslinic) were quite constant, exhibiting a high stability against oxidation. From these results, we can conclude that despite the heating conditions, VOO maintained most of its minor compounds and, therefore, most of its nutritional properties.  相似文献   
72.
Polypropylene (PP) is a widely used plastic with consumer applications ranging from food packaging to automotive parts, including car battery casings. To differentiate it from other recyclable plastics, it is designated as #5. Here, the factors contributing to PP recycling rates are briefly reviewed. Considerations include collection and separation efficiency, processing chemistry, and market dynamics for the products derived from recyclates.  相似文献   
73.
Laurus nobilis L. leaves are widely used in cooking and in folk medicine. Five new megastigmane glucosides (2-4, 7, and 9) named laurosides A-E and a new phenolic glucoside 12 were isolated from the methanolic extract of L. nobilis L. leaves, along with 10 known components: megastigmane (5), megastigmane glucosides (1, 6, 8, 10, and 11), aromatic compounds (13 and 14), and flavonoids (15 and 16). The structures and relative stereochemistry have been elucidated by one- and two-dimensional nuclear magnetic resonance experiments ((1)H and (13)C NMR, DEPT, correlation spectroscopy, heteronuclear multiple quantum correlation, heteronuclear multiple bond correlation, and nuclear Overhauser enhancement spectroscopy) and by chemical derivatization. The effect of isolated compounds on nitric oxide production in lipopolysaccharide-activated murine macrophages were examined.  相似文献   
74.
Rhizosphere and bulk soil samples were taken from two perennial plant species (the palm Bactris gasipaes and the dicot Theobroma grandiflorum) growing in an experimental polyculture agroforestry system in Central Amazonia in the wet and the dry season. In the dry season, the soil water potential in the rhizosphere and the bulk soil was below pF 4.2. Microbial biomass and basal respiration were lower in the dry season than in the wet season. However, the lower metabolic quotient in the dry season indicated a higher metabolic efficiency. While the number of oligotrophic microorganisms was not affected by the season, the number of eutrophic microorganisms in the rhizosphere was lower in the dry season than in the wet season. The substrate utilisation pattern of the bacterial community was also affected by the season. Despite marked differences in root morphology there were no significant differences in any of the microbiological parameters between the two plant species. It is concluded that during the dry season, a large portion of the microbial biomass dies off or enters a dormant stage resulting in a change in community composition.  相似文献   
75.
Three new furostanol saponins named capsicoside E (1), capsicoside F (2), and capsicoside G (5) were obtained from the seeds of Capsicum annuum L. var. acuminatum along with known oligoglycosides (3, 4, and 6-10). On the basis of chemical and spectroscopic analyses, the structures of these new furostanol oligoglycosides were elucidated as 26-O-beta-D-glucopyranosyl-22-O-methyl-5alpha-furost-25(27)-en-2alpha,3beta,22xi,26-tetraol-3-O-beta-D-glucopyranosyl(1-->3)-beta-D-glucopyranosyl(1-->2)-[beta-D-glucopyranosyl(1-->3)]-beta-D-glucopyranosyl(1-->4)-beta-D-galactopyranoside (1), 26-O-beta-D-glucopyranosyl-(25R)-5alpha-furost-20(22)-en-2alpha,3beta,26-triol-3-O-beta-D-glucopyranosyl (1-->3)-beta-D-glucopyranosyl(1-->2)-[beta-D-glucopyranosyl(1-->3)]-beta-D-glucopyranosyl(1-->4)-beta-D-galactopyranoside (2), and 26-O-beta-D-gluco-pyranosyl-(25R)-5alpha-furosta-3beta,22xi,26-triol-3-O-beta-D-glucopyranosyl(1-->3)-beta-D-glucopyranosyl(1-->2)-[beta-D-glucopyranosyl(1-->3)]-beta-D-glucopyranosyl(1-->4)-beta-D-galactopyranoside (5). The isolated saponins showed higher antimicrobial activity against yeasts than against common fungi. Data indicated that the antiyeast activity was related to the combination of the oligosaccharide chain (S1, S2, or S3) with an O-methyl group at R(3) and the presence of a hydroxyl group at the C-2 position.  相似文献   
76.
A mixed-breed pygmy goat was presented for nonambulatory tetraparesis. Neurological examination was consistent with a C6 to T2 myelopathy. Initially, the goat was treated medically. Forty-three days later, magnetic resonance imaging (MRI) revealed an extradural mass compressing the cervical spinal cord. Magnetic resonance attributes of the mass were consistent with a slow-growing, fluid-poor lesion. The spinal cord was surgically decompressed. Epidural empyema secondary to Fusobacterium necrophorum was identified. Postoperative care consisted of anti-inflammatory medication, antimicrobials, and physical therapy. Ability to walk occurred by day 14 after surgery. Despite prolonged recumbency before surgery, the goat was clinically normal, and antimicrobials were discontinued on day 60 after surgery.Key clinical message:Epidural empyema can cause a compressive myelopathy which may result in varying degrees of paresis/paralysis. Clinical resolution and return of normal function occurred following the use of MRI to plan surgical decompression combined with extended use of antimicrobials.  相似文献   
77.
The present study aimed to compare the welfare of dairy cows kept in two traditional husbandry systems (semi-intensive and intensive farming) in south-eastern Sicily. A total of 18 dairy farms (nine semi-intensive and nine intensive) were evaluated with a multicriteria system adapted for Sicilian conditions and obtained simplifying the model of the European Food Safety Authority (EFSA). Values of welfare measures, collected by inspections of the farms (general well-being indicators, ventilation system, resting areas [cubicles or bedding], flooring, milking parlours and waiting area, manger and watering equipment), and those of health categories (cases of abortions, hypocalcemia, displacement of abomasum, acidosis/ketosis, enteritis, hoof problems, and mastitis) obtained through the farm records, were compared using Mann–Whitney and Chi-squared tests, respectively. Data showed significant differences (p ≤ .05) about the variables related to welfare categories such as housing ventilation system, resting area, manger, and water equipment that were better in the semi-intensive system than the intensive system. No significant differences were observed about the variables related to health indicators. The results demonstrated that in Sicily the semi-intensive farm is better than the intensive to satisfy the conditions of animal welfare.  相似文献   
78.
79.
Background: Greyhounds are known to have a higher systemic arterial blood pressure (BP) than non‐Greyhound dogs. Objectives: The purpose of this study was to determine whether the high systemic BP was because of the white‐coat effect. Animals: Twenty‐two healthy retired racing Greyhounds (RRG) enrolled in a blood donation program. Materials/Methods: We prospectively measured systemic BP in 3 environments: in the hospital by the investigator (Hosp), in the home by the investigator (H/I), and in the home by the owner (H/O). Five serial measurements of systolic, diastolic, and mean arterial pressures (SAP, DAP, MAP) as well as heart rate (HR) were measured by an oscillometric method on the distal forelimb and distal hind limb in all 3 environments. Results: There was a significant difference for SAP, MAP, and HR between the Hosp and both H/I and H/O (P < .001); there were no significant differences for any of the parameters between the H/I and H/O environments. HR, but not SAP, MAP, or DAP (P < .05) decreased in RRG with multiple hospital visits for blood donation before this study. The hind limb SAP was significantly higher than the forelimb SAP (P < .05). Conclusions and Clinical Importance: We conclude that the high SAP, MAP, and HR seen in the hospital setting are likely because of a white‐coat effect. Furthermore, consideration should be given to defining the parameters of normal BP in RRG according to the environment in which they are obtained.  相似文献   
80.
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