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11.
We investigated changes in the antioxidant and enzyme activities of cooked, mini, super-sweet corn (Zea mays L. saccharata ‘Naulthong’). After steaming, samples of whole-ear and cut mini corncobs were vacuum- or atmospheric-packaged then frozen for 6 months. Lutein, zeaxanthin, ferulic acid, total phenolics, 2,2′-azinobis-3-[ethylbenzothiazoline-6-sulfonic acid] (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric-reducing antioxidant power (FRAP) generally decreased in relation to storage time, which differed significantly depending on the serving pattern and type of packaging. Cut pieces with atmospheric packaging had the highest peroxidase (POD) and lipoxygenase (LOX) activity. For all storage periods, whole ears had higher levels of bioactive compounds and antioxidant activity than cut-pieces. Vacuum-packaging provided greater quality maintenance than atmospheric-packaging of frozen, cooked, mini, super-sweet ears. Preparation style and packaging during frozen storage affect nutritional quality and guide consumer choices.  相似文献   
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13.
Cardiovascular disease (CVD) is the single largest cause of mortality in the United States and worldwide. Numerous risk factors have been identified for CVD, including a number of nutritional factors. Recently, attention has been focused on fructose-containing sugars and their putative link to risk factors for CVD. In this review, we focus on recent studies related to sugar consumption and cardiovascular risk factors including lipids, blood pressure, obesity, insulin resistance, diabetes, and the metabolic syndrome. We then examine the scientific basis for competing recommendations for sugar intake. We conclude that although it appears prudent to avoid excessive consumption of fructose-containing sugars, levels within the normal range of human consumption are not uniquely related to CVD risk factors with the exception of triglycerides, which may rise when simple sugars exceed 20% of energy per day, particularly in hypercaloric settings.  相似文献   
14.
Abstract

In previous work using gold as a model substrate, we showed that modification of surfaces with poly(ethylene glycol) (PEG) and corn trypsin inhibitor (CTI) rendered them protein resistant and inhibitory against activated factor XII. Sequential attachment of PEG followed by CTI gave superior performance compared to direct attachment of a preformed PEG-CTI conjugate. In the present work, a sequential method was used to attach PEG and CTI to a polyurethane (PU) substrate to develop a material with applicability for blood-contacting medical devices. Controls included surfaces modified only with PEG and only with CTI. Surfaces were characterized by water contact angle and X-ray photoelectron spectroscopy. The surface density of CTI was in the range of a monolayer and was higher on the PU substrate than on gold reported previously. Biointeractions were investigated by measuring fibrinogen adsorption from buffer and plasma, factor XIIa inhibition and plasma clotting time. Both the PU–PEG surfaces and the PU–PEG–CTI surfaces showed low fibrinogen adsorption from buffer and plasma, indicating that PEG retained its protein resistance when conjugated to CTI. Although the CTI density was lower on PU–PEG–CTI than on PU modified only with CTI, PU–PEG–CTI exhibited greater factor XIIa inhibition and a longer plasma clotting time, suggesting that PEG facilitates the interaction of CTI with factor XIIa. Thus sequential attachment of PEG and CTI may be a useful approach to improve the thromboresistance of PU surfaces.  相似文献   
15.
本研究旨在探索不同切碎长度和发酵方式对全株饲用青贮谷子质量的影响。采用2×3双因子试验设计,切割长度分别为1.5 cm、2.5 cm和3.5 cm,发酵方式分为复合菌剂发酵和乳酸菌发酵两个类型,每处理3个重复。常温发酵40 d后取样,进行感官评定,分析基础养分,测定挥发性成分。结果表明,随着切碎长度增加,气味评分和总分总体呈降低趋势,中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)含量呈增加趋势,丁酸含量显著增加;相比乳酸菌发酵组,复合菌剂发酵组整体气味评分和乳酸含量较高,pH值和NDF、ADF含量较低。综上,不同切碎长度和发酵方式对于全株饲用谷子青贮质量均有显著影响。降低切碎长度和使用复合菌剂发酵均有助于促进纤维分解,减少丁酸产量,改善青贮感官评分。  相似文献   
16.
Chiam-Wen Liew  S. Ramesh 《Materials》2014,7(5):4019-4033
Two different ionic liquid-based biopolymer electrolyte systems were prepared using a solution casting technique. Corn starch and lithium hexafluorophosphate (LiPF6) were employed as polymer and salt, respectively. Additionally, two different counteranions of ionic liquids, viz. 1-butyl-3-methylimidazolium hexafluorophosphate (BmImPF6) and 1-butyl-3-methylimidazolium trifluoromethanesulfonate (also known as 1-butyl-3-methylimidazolium triflate) (BmImTf) were used and studied in this present work. The maximum ionic conductivities of (1.47 ± 0.02) × 10−4 and (3.21 ± 0.01) × 10−4 S·cm−1 were achieved with adulteration of 50 wt% of BmImPF6 and 80 wt% of BmImTf, respectively at ambient temperature. Activated carbon-based electrodes were prepared and used in supercapacitor fabrication. Supercapacitors were then assembled using the most conducting polymer electrolyte from each system. The electrochemical properties of the supercapacitors were then analyzed. The supercapacitor containing the triflate-based biopolymer electrolyte depicted a higher specific capacitance with a wider electrochemical stability window compared to that of the hexafluorophosphate system.  相似文献   
17.
BackgroundDietary intake of sugar-sweetened beverages (SSBs) has increased during the past 30 years, and SSB intake is associated with caries.
ConclusionsSSBs vary in the quantity and nature of sugars they contain; however, all of the sugars are fermentable by oral bacteria and potentially cariogenic.Practical ImplicationsOral health care practitioners should assess patients’ SSB intakes by asking questions regarding the quantity, frequency and duration of SSB intake. In response to individual behaviors, practitioners should tailor recommendations when providing anticipatory guidance to help patients decrease their exposure to SSBs for caries prevention. In light of the association between SSB intake and caries risk, as well as the increased consumption of SSBs, all dental practices should assess patients’ SSBs intake.  相似文献   
18.
目的:通过观察大鼠进食含高果糖玉米糖浆(high fructose corn syrups,HFCS)饲料后牙齿的患龋情况,评价HFCS的致龋性.方法:选择适龄SPF级远交群大鼠(Spraque-Dawley,SD)30只,抑制口腔固有菌群后接种变异链球菌UA159,并随机分为3组,分别用不含糖饲料、含蔗糖饲料和含HFCS饲料喂养3个月.3个月后截取上下颌骨,体视显微镜观察磨牙颊舌面龋损;制作磨牙纵磨片,荧光染色后用荧光显微镜观察(牙合)面和邻面龋损情况,并根据Keyes评分法评价龋损程度.结果:3组大鼠的患龋率均为100%.HFCS组与蔗糖组的龋损程度无统计学差异(P>0.05);蔗糖组各牙面的龋齿记分均显著高于不含糖饲料组(P<0.05);HFCS组中,窝沟龋全层、平滑面龋釉质和牙本质外层1/4的龋齿记分均明显高于不含糖饲料组(P<0.05),而平滑面龋损深度超过牙本质厚度1/4的龋齿记分与不含糖饲料组比较无统计学差异(P>0.05).结论:含HFCS的饮食能导致SD大鼠发生龋病,其龋损程度与蔗糖相近.  相似文献   
19.
目的 测定不同类型淀粉类黏合剂的黏度曲线,确定其使用的最佳浓度范围。方法 探索不同类型淀粉的配制方法,采用数字旋转黏度计测定不同种类淀粉黏合剂在不同温度下的黏度并绘制黏度曲线图。结果 不同种类的淀粉制成淀粉浆的黏度差异较大;所考察的5种淀粉浆的黏度拐点温度范围为40~50℃;预胶化淀粉和部分预胶化淀粉适合采用煮桨法配制淀粉浆,其他3种淀粉适合采用冲浆法配制淀粉浆。结论 作为淀粉浆使用的最佳浓度范围分别是:玉米淀粉5%~8%,可溶性淀粉6%~8%,预胶化淀粉5%~8%,部分预胶化淀粉5%~8%,SWELSTARTMWB-1 1%~5%。  相似文献   
20.
鹿茸为雄性梅花鹿或马鹿尚未骨化、带茸毛的幼角经制成的中药,相关药理学研究表明其中的成分可通过促进成骨细胞增殖的同时诱导破骨细胞凋亡,调节骨代谢。本文对近年来鹿茸提取物及复方制剂调节骨代谢方面的研究进行综述,包括基础研究、动物模型研究及临床研究,以期为运用鹿茸防治骨质疏松提供参考。  相似文献   
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