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排序方式: 共有642条查询结果,搜索用时 15 毫秒
621.
Renata Siqueira Scatolin Fernando Luiz Alonso‐Filho Rodrigo Galo Daniela Rios Maria Cristina Borsatto Silmara Aparecida Milori Corona 《Microscopy research and technique》2015,78(8):654-659
Considering the importance and prevalence of dental erosion, the aim of this in vitro study was to evaluate the influence of different modes of pulse emission of CO2 laser associated or not to acidulated phosphate fluoride (APF) 1.23% gel, in controlling enamel erosion by profilometry. Ninety‐six fragments of bovine enamel were flattened and polished, and the specimens were subjected to initial erosive challenge with hydrochloric acid (pH = 2). Specimens were randomly assigned according to surface treatment: APF 1.23% gel and gel without fluoride (control), and subdivided according to the modes of pulse CO2 laser irradiation: no irradiation (control), continuous, ultrapulse, and repeated pulse (n = 12). After surface treatment, further erosive challenges were performed for 5 days, 4 × 2 min/day. Enamel structure loss was quantitatively determined by a profilometer, after surface treatment and after 5 days of erosive challenges. Two‐away ANOVA revealed a significant difference between the pulse emission mode of the CO2 laser and the presence of fluoride (P ≤ 0.05). The Duncan's test showed that CO2 laser irradiation in continuous mode and the specimens only received fluoride, promoted lower enamel loss than that other treatments. A lower dissolution of the enamel prisms was observed when it was irradiated with CO2 laser in continuous mode compared other groups. It can be concluded that CO2 laser irradiation in continuous mode was the most effective to control the enamel structure loss submitted to erosive challenges with hydrochloric acid. Microsc. Res. Tech. 78:654–659, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
622.
Rosana Aparecida Manólio Soares Simone Mendon?a Luíla ívini Andrade de Castro Amanda Caroline Cardoso Corrêa Carlos Menezes José Alfredo Gomes Arêas 《International journal of molecular sciences》2015,16(2):4150-4160
The objective of this study was to identify the major peptides generated by the in vitro hydrolysis of Amaranthus cruentus protein and to verify the effect of these peptides on the activity of 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMG-CoA reductase), a key enzyme in cholesterol biosynthesis. A protein isolate was prepared, and an enzymatic hydrolysis that simulated the in vivo digestion of the protein was performed. After hydrolysis, the peptide mixture was filtered through a 3 kDa membrane. The peptide profile of this mixture was determined by reversed phase high performance chromatography (RP-HPLC), and the peptide identification was performed by LC-ESI MS/MS. Three major peptides under 3 kDa were detected, corresponding to more than 90% of the peptides of similar size produced by enzymatic hydrolysis. The sequences identified were GGV, IVG or LVG and VGVI or VGVL. These peptides had not yet been described for amaranth protein nor are they present in known sequences of amaranth grain protein, except LVG, which can be found in amaranth α‑amylase. Their ability to inhibit the activity of HMG-CoA reductase was determined, and we found that the sequences GGV, IVG, and VGVL, significantly inhibited this enzyme, suggesting a possible hypocholesterolemic effect. 相似文献
623.
Paulo Salgado Joo PB Freire Ricardo B Ferreira Artur Teixeira Oflia Bento Manuel C Abreu Ren Toullec Jean‐Paul Lalls 《Journal of the science of food and agriculture》2003,83(15):1571-1580
Experiments were conducted to investigate the biochemistry of digestion of the major storage proteins from soya bean, pea, faba bean, blue lupin, and chickpea seeds in the ileum of piglets. Hyperimmune plasmas against the crude protein extracts and the purified 11S and 7S globulin fractions of each legume seed and an anti‐pea albumin PA2 and lectin antibody were used. They served to probe immunoblots of feed protein extracts and ileal digesta samples. Globally, the recognition by plasmas of intact or partially digested proteins in ileal digesta was rather faint, in agreement with the fairly high in vivo digestibility data obtained with these legume seed proteins. Nevertheless, immunoreactive polypeptides found in digesta of piglets fed pea, faba bean and chickpea belonged mainly to proteins of the 7S family, and to other proteins including low‐molecular weight components such as PA2 albumin and lectin in the case of pea. In piglets fed lupin, nearly intact polypeptides from the 11S family were detected. To conclude, the present immunochemical study conducted on ileal digesta of piglets revealed a few dietary legume proteins of the vicilin and albumin families. Legumin proteins were demonstrated unequivocally in the case of lupin and white chickpea. Copyright © 2003 Society of Chemical Industry 相似文献
624.
Cleonice Gonçalves da Rosa Caroline Dellinghausen Borges Rui Carlos Zambiazi Josiane Kuhn Rutz Suzane Rickes da Luz Fernanda Döring Krumreich Edilson Valmir Benvenutti Michael Ramos Nunes 《LWT》2014
Microencapsulated phenolic extracts of blackberry (PE) were obtained by lyophilization in matrixes of β-cyclodextrin (β-CDS), chitosan (C), xanthan (X) and hydrogel (H). The encapsulation was confirmed by Scanning Electron Microscopy (SEM) and Thermogravimetric Analysis (TGA); their antioxidant activity, controlled release of phenolics and efficiency of encapsulation were determined. However, coated chitosan and xanthan only showed the characteristic shape. In fact, encapsulation efficiency depended on the phenolic compound and the encapsulated coating used; gallic acid and epicatechin were predominantly in microcapsules coated with β-cyclodextrin and xanthan. The highest antioxidant activity in microcapsules coated with β-cyclodextrin (84.43 ± 3.5%) and xanthan (90.75 ± 0.09%) was related to the equitable presence of encapsulated phenolic compounds. The controlled release of phenolic extract capsules was influenced by coating, solvent and pH. 相似文献
625.
626.
Daniel Galafassi Camila Scatena Vivian Colucci Antonio Luiz Rodrigues Júnior Mônica Campos Serra Silmara Aparecida Milori Corona 《Microscopy research and technique》2014,77(1):37-43
This study evaluates the bond strength of dentin prepared with Er:YAG laser or bur, after rewetting with chlorhexidine on long‐term artificial saliva storage and thermocycling. One hundred and twenty human third molars were sectioned in order to expose the dentin surface (n = 10). The specimens were randomly divided in 12 groups according to treatment and aging: Er:YAG laser rewetting with deionized water (LW) and 24 h storage in artificial saliva (WC); LW and 6 months of artificial saliva storage + 12.000 thermocycling (6M), LW and 12 months of artificial saliva storage + 24.000 thermocycling (12M), Er:YAG laser rewetting with 2% chlorhexidine (LC) and WC, LC and 6M, LC and 12M, bur on high‐speed turbine rewetting with deionized water (TW) and WC, TW6M, TW12M, bur on high‐speed turbine + 2% chlorhexidine (TC) and WC, TC and 6M, TC and12M. The specimens were etched with 35% phosphoric acid, washed, and dried with air. Single Bond 2 adhesive was applied and the samples were restored with a composite. Each tooth was sectioned in order to obtain 4 sticks, which were submitted to microtensile bond strength test (µTBS). The two‐way ANOVA, showed no significant differences for the interaction between the factors and for the aging factor. Tukey 5% showed that the LC group had the lowest µTBS. The rewetting with chlorhexidine negatively influenced the bond strength of the preparation with the Er:YAG laser. The artificial saliva aging and thermocycling did not interfere with dentin bond strength. Microsc. Res. Tech. 77:37–43, 2014. © 2013 Wiley Periodicals, Inc. 相似文献
627.
Effect of different irrigation protocols on the radicular dentin interface and bond strength with a metacrylate‐based endodontic sealer
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Lisandro Gonçalves Yara Teresinha Correa Silva‐Sousa Walter Raucci Neto Cleonice Silveira Teixeira Manoel Damião Sousa‐Neto Edson Alfredo 《Microscopy research and technique》2014,77(6):446-452
This study assessed the influence of different endodontic chemical substances on the adhesion of the Epiphany SE/Resilon system (with and without resinous solvent) to radicular dentin walls, using the push‐out test and scanning electron microscopy (SEM). Forty‐eight root canals of human canines were prepared biomechanically with ProTaper rotary files (crown‐down technique) and the radicular dentin was treated with either 17% EDTA, 2% chlorhexidine gel (CHX) or 2.5% NaOCl (control). The root canals were filled with Resilon cones and Epiphany SE sealer with and without resinous solvent. Six groups of eight canals each had their roots sectioned transversally to obtain 1‐mm thick slices. Data were subjected to statistical analysis by ANOVA and Tukey's tests. The specimens treated with 17% EDTA (1.59 ± 0.91) presented higher bond strength (P < 0.05) than those treated with 2.5% NaOCl (0.93 ± 0.27) and 2% CHX (0.92 ± 0.22). Significantly higher bond strength (P < 0.05) was observed when the Epiphany SE was prepared with (1.37 ± 0.78) than without (0.92 ± 0.33) solvent. Adhesive failures were predominant in all groups. SEM analysis showed greater homogeneity of the filling mass when the solvent was added to the sealer. Treatment of root canal walls with 17% EDTA, and addition of a resinous solvent to Epiphany SE produced the highest adhesion to radicular dentin. Microsc. Res. Tech. 77:446–452, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
628.
C. E. Orrego N. Salgado C. A. Botero 《Critical reviews in food science and nutrition》2014,54(1):84-97
Fruits serve as a source of energy, vitamins, minerals, and dietary fiber. One of the barriers in increasing fruit and vegetables consumption is time required to prepare them. Overall, fruit bars have a far greater nutritional value than the fresh fruits because all nutrients are concentrated and, therefore, would be a convenience food assortment to benefit from the health benefits of fruits. The consumers prefer fruit bars that are more tasted followed by proper textural features that could be obtained by establishing the equilibrium of ingredients, the proper choosing of manufacturing stages and the control of the product final moisture content. Fruit bar preparations may include a mixture of pulps, fresh or dried fruit, sugar, binders, and a variety of minor ingredients. Additionally to the conventional steps of manufacturing (pulping, homogenizing, heating, concentrating, and drying) there have been proposed the use of gelled fruit matrices, dried gels or sponges, and extruders as new trends for processing fruit bars. Different single-type dehydration or combined methods include, in order of increasing process time, air-infrared, vacuum and vacuum-microwave drying convective-solar drying, convective drying, and freeze drying are also suggested as alternative to solar traditional drying stage. The dehydration methods that use vacuum exhibited not only higher retention of antioxidants but also better color, texture, and rehydration capacity. Antioxidant activity resulting from the presence of phenolic compounds in the bars is well established. Besides this, fruit bars are also important sources of carbohydrates and minerals. Given the wide range of bioactive factors in fresh fruits that are preserved in fruit bars, it is plausible that their uptake consumption have a positive effect in reducing the risk of many diseases. 相似文献
629.
Carolina Castilho Garcia Lidimara Cássia Caetano Keila de Souza Silva Maria Aparecida Mauro 《Food and Bioprocess Technology》2014,7(10):2828-2839
The edible coating applied to food pieces prior to hot air drying is a technology that can improve the nutritional and sensory qualities of dehydrated products. The effects of the pectin coating technique on the drying efficiency and quality of papaya slices of the Formosa cultivar were investigated, determining the cell structure, color, and vitamin C contents of the fresh and dried fruits, with and without a pectin coating. The drying kinetics was evaluated based on Fick’s Law. The analytical solution for a plane sheet was used to estimate the water effective diffusion coefficients, and, in order to take into account shrinkage during drying, the average and variable thicknesses were considered in an approximate manner. Diffusion modeling presented a better fit when considering the thickness of the slices as variable. Regarding fruit quality, the coating applied to papaya slices before drying enhances vitamin C retention in comparison to papaya dried without coating, showing that pectin coating efficiently prevented oxidation of this bioactive compound. In addition, the moisture diffusivity of the coated samples was higher than that of the non-coated slices, due to the hydrophilic nature of the pectin. Light and transmission electron microscopy images revealed intense rupturing of the cell membranes in the dried tissues. The cell tissue arrangement in the coated papaya slices was similar to that found in the fresh papaya slices, before and after drying. 相似文献
630.