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991.
Jing Luo Jingxin Meng Zhen Gu Luying Wang Feilong Zhang Shutao Wang 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(15)
Self‐organization is a fundamental and indispensable process in a living system. To understand cell behavior in vivo such as tumorigenesis, 3D cellular aggregates, instead of 2D cellular sheets, have been employed as a vivid in vitro model for self‐organization. However, most focus on the macroscale wetting and fusion of cellular aggregates. In this study, it is reported that self‐organization of cells from simple to complex aggregates can be induced by multiscale topography through confined templates at the macroscale and cell interactions at the nanoscale. On the one hand, macroscale templates are beneficial for the organization of individual cells into simple and complex cellular aggregates with various shapes. On the other hand, the realization of these macro‐organizations also depends on cell interactions at the nanoscale, as demonstrated by the intimate contact between nanoscale pseudopodia stretched by adjacent frontier cells, much like holding hands and by the variation in the intermolecular interactions based on E‐cadherin. Therefore, these findings may be very meaningful for clarifying the organizational mechanism of tumor development, tissue engineering and regenerative medicine. 相似文献
992.
Ning Peng Luping Gu Junhua Li Cuihua Chang Xin Li Yujie Su Yanjun Yang 《Food and Bioprocess Technology》2017,10(8):1422-1430
Transglutaminase (TGase) and succinylation could modify the physicochemical characteristics and the functional properties of proteins. The aim of this work was to cross-link egg white protein (EWP) and succinylated casein with TGase and to assess the feasibility of making a novel composite protein film. The effects of succinylated casein content, reaction time, and TGase concentration on the mechanical properties, physical characteristics (thermal property and degree of crystallinity), and structure properties (secondary structure and surface micrograph structure) of the film were investigated in this study. The results revealed that the susceptibility of EWP to TGase-mediated cross-linking modification was enhanced by succinylated casein. Meanwhile, the films with TGase were more homogeneous and smoother and possessed better water resistance and thermal stability. The content of α-helix, β-turn structures were increased whereas β-sheet structure was decreased. The spatial conformation and degree of crystallinity of composite protein film were also affected by TGase. The increase of the degree of crystallinity of the composite film further proved the improvement of film mechanical properties induced by TGase and succinylated casein. Based on the above results, this study provides relevant data and insights for the TGase/chemical modification of protein-based edible films. 相似文献
993.
发芽大豆的营养价值及其复合乳生产技术 总被引:4,自引:0,他引:4
研究了大豆籽粒在发芽过程中营养成分变化和用发芽大豆为原料生产豆乳与牛乳复合的工艺。大豆在发芽过程中 ,随着胚根长度的增加 ,可溶性蛋白质呈先升后降的趋势 ,游离氨基酸始终在增加 ,脂肪和植酸则持续下降。大豆胚根长度 2mm时 ,可溶性蛋白质增加量和植酸减少量分别为浸泡结束时的 5 6 88%和 45 99% ;胚根长度 15mm时 ,游离氨基酸比浸泡结束时增加 1 0 3倍。发芽大豆用质量分数 0 2 %的NaHCO3 溶液 80℃下处理 2min ,经清洗、去皮、热磨、滤浆和煮沸等处理 ,发芽豆乳的豆腥味轻微 ;豆乳与牛乳以体积比 4∶6的比例制成的复合乳营养合理 ,风味协调 相似文献
994.
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997.
推广应用速冻技术发展速冻食品工业 总被引:3,自引:0,他引:3
ApplicationandDisseminationofQuick-freezeTechnologytoDevelopQuick-freezeFoodIndustryGuGanquanZhangDongshengZhengYunbin速冻食品是在零下35t~40℃的环境中2~4min被冻结的食品迅速通过冰晶区,在10~15min时间内完成冻结全过程,使食物中心温度达到一18℃,这样冻结的食品叫速冻食品。速冻技术是近50年来发展起来的新型技术。我国的速冻食品工业比国外先进国家起步较晚,60~对年代通过弓l进国外的设备加工一些速冻蔬菜等。进入90年代,速冻食品工业迅猛地发展起来,据不完全统计,现在全国已有2000多个厂家生产各类不同的速… 相似文献
998.
999.
啤酒生产过程中氧化还原酶系的研究 总被引:10,自引:0,他引:10
啤酒生产过程中的氧化还原酶与啤酒风味陈化紧密相关。低水分下,其耐温活性远高于其它几种酶,在麦芽中酶活升高比例最大(与大麦中的酶活相比),其在糖化过程中氧化多酚的能力远大于多酚氧化酶。糖化过程中迅速失活,而脂肪酸氧化酶在糖化起始的低温阶段仍有部分酶活,影响不饱和脂肪酸的氧化。焙燥过程中适当延长50~70℃温度段时间,可有效降低麦芽中氧化还原酶的酶活。结合这些酶的性质,从部分抑制它们的活性角度出发,在糖化过程中,于50~60℃进行隔氧处理,可经济、有效的减少影响风味氧化的前驱物质的含量。同一质量等级不同品种的麦芽的氧化还原酶系差别相当大,相应制得的麦汁中与风味氧化有关的物质含量也有较大差别,这可能是造成不同批次原料酿造的成品啤酒风味保鲜期不稳定的原因之一。 相似文献
1000.
Zhaosheng Hu Zhe Liu Lin Li Baogang Quan Yunlong Li Junjie Li Changzhi Gu 《Small (Weinheim an der Bergstrasse, Germany)》2014,10(19):3933-3942
Fabricating perfect plasmonic nanostructures has been a major challenge in surface enhanced Raman scattering (SERS) research. Here, a double‐layer stacked Au/Al2O3@Au nanosphere structures is designed on the silicon wafer to bring high density, high intensity “hot spots” effect. A simply reproducible high‐throughput approach is shown to fabricate feasibly this plasmonic nanostructures by rapid thermal annealing (RTA) and atomic layer deposition process (ALD). The double‐layer stacked Au nanospheres construct a three‐dimensional plasmonic nanostructure with tunable nanospacing and high‐density nanojunctions between adjacent Au nanospheres by ultrathin Al2O3 isolation layer, producing highly strong plasmonic coupling so that the electromagnetic near‐field is greatly enhanced to obtain a highly uniform increase of SERS with an enhancement factor (EF) of over 107. Both heterogeneous nanosphere group (Au/Al2O3@Ag) and pyramid‐shaped arrays structure substrate can help to increase the SERS signals further, with a EF of nearly 109. These wafer‐scale, high density homo/hetero‐metal‐nanosphere arrays with tunable nanojunction between adjacent shell‐isolated nanospheres have significant implications for ultrasensitive Raman detection, molecular electronics, and nanophotonics. 相似文献