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81.
This work intended to study the rheological and textural behavior of gluten-free dough for “empanadas” and pie-crusts production. Traditionally, these products are made with non-fermented wheat-based dough. They are highly consumed in Latin America, but unsuitable for celiac people. Gluten matrix is a major determinant of the properties of dough, thus it must be replaced with other network forming components, such as hydrocolloids. Different hydocolloids were tested: hydroxypropylmethylcellulose (HPMC) and mixtures of xanthan/guar, and xathan/HPMC gums. Three different kinds of lipid phase were also studied; i.e. sunflower oil and low and high solid content margarine at two different levels (20–30%). Changes in rheological and textural properties during refrigerated storage were evaluated by dynamic oscillatory measurements and puncture and elongation tests on the unbaked dough. Best results were obtained using either of the hydrocolloid mixtures. Besides, the textural characteristics of cooked empanadas were also studied. Freezing before baking did not alter the quality of the crust in the products. ESEM micrographs revealed a continuous matrix formed by hydrocolloid entanglements. Starch granules were homogenously distributed in the dough and acted as inactive fillers. An untrained panel accepted the xanthan/HPMC dough with a 74/90 score and it was significantly preferred over a commercial gluten-free dough.  相似文献   
82.
The antinociceptive and anti-inflammatory activity of caulerpin was investigated. This bisindole alkaloid was isolated from the lipoid extract of Caulerpa racemosa and its structure was identified by spectroscopic methods, including IR and NMR techniques. The pharmacological assays used were the writhing and the hot plate tests, the formalin-induced pain, the capsaicin-induced ear edema and the carrageenan-induced peritonitis. Caulerpin was given orally at a concentration of 100 μmol/kg. In the abdominal constriction test caulerpin showed reduction in the acetic acid-induced nociception at 0.0945 μmol (0.0103–1.0984) and for dypirone it was 0.0426 μmol (0.0092–0.1972). In the hot plate test in vivo the inhibition of nociception by caulerpin (100 μmol/kg, p.o.) was also favorable. This result suggests that this compound exhibits a central activity, without changing the motor activity (seen in the rotarod test). Caulerpin (100 μmol/kg, p.o.) reduced the formalin effects in both phases by 35.4% and 45.6%, respectively. The possible anti-inflammatory activity observed in the second phase in the formalin test of caulerpin (100 μmol/kg, p.o.) was confirmed on the capsaicin-induced ear edema model, where an inhibition of 55.8% was presented. Indeed, it was also observed in the carrageenan-induced peritonitis that caulerpin (100 μmol/kg, p.o.) exhibited anti-inflammatory activity, reducing significantly the number of recruit cells by 48.3%. Pharmacological studies are continuing in order to characterize the mechanism(s) responsible for the antinociceptive and anti-inflammatory actions and also to identify other active principles present in Caulerpa racemosa.  相似文献   
83.
The antiproliferative activity of fresh fruit juices extracted from Citrus sinensis (cv. Washington Navel and cv. Sanguinello), C. deliciosa cv. Avana, C. clementina cv. Nules, C. aurantium subsp. myrtifolia , was evaluated against K562 (human chronic myelogenous leukemia), HL-60 (human leukemia) and MCF-7 (human breast adenocarcinoma) cell lines. All the juices tested showed antiproliferative activity. Moreover, the pattern of the main flavanone compounds in the juices has been determined by HPLC analysis.  相似文献   
84.
Turnover of nitrogen-rich root nodules follows the pruning of legume trees, forming a potentially important yet little studied way of N release to the soil. The effects of soil moisture, herbivory by soil mesofauna and microbial decomposition on the disappearance rate of woody legume nodules was studied in two tree/grass forage production associations. Litter bags containing nodules of Erythrina variegata L. (Papilionoideae: Phaseoleae) were incubated for four weeks in grass-covered alleys between Gliricidia sepium (Jacq.) Walp. (Papilionoideae: Robinieae) hedgerows, established on a deep alluvial Oxisol under a humid tropical climate and on a shallow Vertisol under a subhumid tropical climate in Guadeloupe, French Antilles. Soil moisture was regulated by irrigating or covering small plots from natural rainfall. Fine nylon mesh bags were used to study the rate of microbial decomposition, and open-ended perforated cylinders were used to estimate nodule herbivory. The chemical traits, especially the lignin: nitrogen ratio, of E. variegata and G. sepium nodules were similar (lignin: N 1.70 and 1.55, respectively), and suggest that the results are probably also applicable to the G. sepium nodules in the associations. Both soil moisture and decomposing agent (microbes or mesofauna) had a significant effect on the nodule disappearance rate, but soil type did not have any apparent effect. The nodule half-life varied from three to seven days under different treatments. The N release rate from the nodules was high, with N half-life varying from three to five days. Herbivory accounted for ca. 10% of total mass and N loss from nodules during the four-week field incubation period, but its importance increased towards the end of the incubation, especially in Vertisol, after the most easily decomposable part of the nodules had decayed. After pruning, the nodule N is released to soil more rapidly than from mulch. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
85.
To compare the phenolic responses under oxidative stressors, plants of two Italian cultivars of durum wheat (Claudio and Mongibello) were (a) exposed to ozone (O3) (80 ppb, 5 hr/day for 70 consecutive days), with the aim to investigate the changes of phenolic compound contents in their leaves, or (b) flooded (seven consecutive days). Plants showed O3-induced visible injury, but their photosynthetic performance was not affected by the pollutant. Specifically, Claudio showed a higher O3 tolerance than Mongibello. The major value of the present study is undoubtedly the pioneering investigation of phenolic metabolism of durum wheat under O3. We identified 12 foliar phenolic compounds in all leaf samples (i.e. controls, exposed to O3 and flooded): ten phenolic acids, a flavanol (catechin hydrate) and a phenolic aldehyde (syringaldehyde). Overall, O3 exposure resulted in accumulations of phenolic compounds, especially in Claudio. These responses can be likely considered a fine-regulated repair process that equipped Claudio stressed plants with an antioxidant system capable of scavenging oxidative stress. Different phenolic variations were found in flooded plants, suggesting that phenolic response to environmental constraints is stress specific. Our study confirms that investigations and characterization of specific phenolic profiles of crop cultivars under oxidative stress may be helpful in breeding programmes.  相似文献   
86.
Disorders of the reproductive system represent a large portion of both large and small domestic animal medicine. Although some disorders of this system have been extensively studied in birds, this science is still in its infancy, when compared to mammalian reproductive medicine. This may be due to several reasons, but the simple fact that birds are oviparous renders knowledge of mammalian reproductive anatomy, histology, physiology, and disease process, inapplicable to avian patients. Nevertheless, several specific diseases or conditions affecting the reproductive system of birds have been described. By integrating information about the comparative anatomy and physiology of birds, reports of the most common reproductive diseases of birds and utilizing the latest diagnostic techniques, especially videoendoscopy, the avian practitioner should be able to diagnose and properly treat a high percentage of the avian reproductive diseases.  相似文献   
87.
Cytosine arabinoside (ara‐C) is a component of many protocols for the treatment of acute leukaemia and non‐Hodgkin lymphomas in humans. The aim of the study was to prospectively evaluate the efficacy of ara‐C in a myeloablative regimen in a cohort of canine lymphomas with bone marrow involvement. Seventeen dogs were enrolled. Eight were treated with a VCAA‐based protocol (Group 1) and nine with the same regimen added with ara‐C (Group 2). Ara‐C was administered on a 5‐day schedule as an i.v. continuous infusion at the dose of 150 mg m?2 per day for five consecutive days. During treatment complete remission (CR) was achieved in two dogs in Group 1 and in eight dogs in Group 2. CR rate was significantly higher in Group 2 (P < 0.01). Median survival was 72.5 days (range 6–174) in Group 1 and 243 days (range 73–635) in Group 2. Survival was significantly longer in Group 2 (P < 0.001). Both protocols were well tolerated, with a low incidence of adverse events. Ara‐C added to a VCAA‐based protocol appears to be safe and beneficial in dogs with stage V lymphoma. Incorporation of the nucleoside analogue might be crucial for the development of future therapeutic strategies in dogs.  相似文献   
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Artificial inoculation with fungal species involved in the Petri disease was performed on in vitro grapevine shoots. After 2 months, plantlets were observed and the presence of any leaf chlorosis or necrosis, considered as symptoms of the disease, were recorded. The fungal inoculation caused an increase in the number of symptomatic in vitro plants and in the incidence of external symptoms. Recovery of the fungal species was obtained after incubation of excised tissue fragments from the inoculated in vitro plants while some fertile fragments were collected also from plants without external symptoms. Higher levels of symptoms were observed in the rootstock varieties inoculated with Phaeomoniella chlamydospora while the lowest incidence was observed in the Aglianico cultivar. The possibility to correlate the visual assessment of in vitro plants with the data obtained by the analysis of digital images was confirmed.  相似文献   
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