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151.
为促进肉制品生产的多样性并同时拓展果蔬的应用领域,使得肉制品营养、保健、色泽诱人且口味独特,在肉制品的加工中添加果蔬形成复合果蔬肉制品,已经成为肉制品发展的一个新方向,开发及应用前景广阔。果蔬的添加形式与添加量、工艺路线等因产品形式不同而异。本文综述了近年来复合果蔬肉制品的研究进展情况,包括原料研究、新产品的开发、关键技术研究、研究与应用存在的一些主要问题及应对策略,以期为肉类深加工、果蔬的充分利用及高档复合肉制品的开发提供借鉴参考。   相似文献   
152.
本文旨在研究不同提取方法(水酶法;溶剂法;冷榨法)对葵花油的脂肪酸组成、理化性质、酚类物质、生育酚含量、抗氧化活性和氧化稳定性的影响。采用了清除DPPH自由基、抑制β-胡萝卜素-亚油酸乳化体系褪色实验和清除ABTS+·阳离子方法评价葵花油的抗氧化活性,并通过等温DSC测定了三种葵花油的氧化稳定性。结果表明:提取方法对葵花油脂肪酸组成的影响不显著(p<0.05)。与溶剂法和水酶法相比,冷榨法葵花油表现出较优质的产品特性。溶剂法葵花油的总酚含量(TPC,0.29 mg/g)、邻苯二酚含量(ODC,0.45 mmol/kg)和总生育酚含量(TTC,1090.81 mg/kg)最高,并且具有最强的DPPH自由基(IC50,3.54 mg/m L)、ABTS+·阳离子清除能力(TEAC,652.33μmol/L)以及最强的抑制β-胡萝卜素褪色能力(C%,45.93%)。不同提取方法对葵花油的氧化稳定性影响显著(p<0.05),氧化稳定性依次为:溶剂法>水酶法>冷榨法。   相似文献   
153.
分析了不同温度热处理及不同时间热处理的大豆分离蛋白体外模拟消化过程产物的荧光光谱。结果表明:不同时间热处理及不同温度的热处理均对大豆蛋白的消化有一定促进作用,大豆蛋白的最佳热处理条件为85℃、20 min,蛋白质的消化程度最大。大豆分离蛋白经不同温度热处理后,消化1 h,消化产物的最大吸光波长(λmax)即随着加热温度的上升而红移,在加热90℃时达到最大值后下降,而荧光强度呈现出先上升后下降的变化趋势。经过不同时间热处理后消化1 h,大豆分离蛋白消化产物的λmax先上升后下降。且荧光强度随着加热时间的延长呈现出不同的变化趋势,在020 min不断升高时,20 min时达到最大值,而继续加热至60 min,荧光强度逐渐下降。   相似文献   
154.
本实验旨在优化氧化锆珠破壁方法,以期筛选出较佳的破壁条件,提高蛋白得率。实验在菌体重量、研磨buffer和研磨时间这3方面对该破壁方法进行了优化,并通过SDS-PAGE来分析其破壁效果。在优化后的条件下,同时对6株乳酸菌进行破壁处理并通过SDS-PAGE来分析其破壁效果。结果表明:在菌体重量、研磨buffer、锆珠三者的加入比例(W/V/W)为0.013 g∶300μL∶1 g的条件下,研磨15 min,提取的蛋白图谱条带清晰,丰度高;RIPA、PBS、PENP、GUS作为研磨buffer时,提取的蛋白图谱条带清晰且丰度高,而8 mol/L尿素作为研磨buffer时,图谱条带模糊且丰度低;6株乳酸菌经该方法破壁处理后,蛋白图谱条带均具有较高的丰度和清晰度。因此,对于乳酸菌的破壁,氧化锆珠破壁法具有快速、高效的优点。   相似文献   
155.
随着无人艇自主控制技术的发展,其在军事领域的作用日益突出,反水雷无人艇的自主控制技术是目前研究的热点之一.针对反水雷无人艇的局部路径规划问题进行研究,提出一种分层强化学习方法,对作为无人艇路径规划器的进化神经网络进行训练.同时使用Unity物理引擎搭建仿真环境,构建了具有环境感知和自主决策能力的无人艇模型.试验验证表明...  相似文献   
156.
Bmpr2 plays a central role in the regulation of reproductive development in mammals, but its role during ovarian development in fish is still unclear. To ascertain the function of bmpr2 in ovarian development in the ricefield eel, we isolated and characterized the bmpr2 cDNA sequence; the localization of Bmpr2 protein was determined by immunohistochemical staining; and the expression patterns of bmpr2 in ovarian tissue incubated with FSH and hCG in vitro were analyzed. The full-length bmpr2 cDNA was 3311 bp, with 1061 amino acids encoded. Compared to other tissues, bmpr2 was abundantly expressed in the ovary and highly expressed in the early yolk accumulation (EV) stages of the ovary. In addition, a positive signal for Bmpr2 was detected in the cytoplasm of oocytes in primary growth (PG) and EV stages. In vitro, the expression level of gdf9, the ligand of bmpr2, in the 10 ng/mL FSH treatment group was significantly higher after incubation for 4 h than after incubation for different durations. However, bmpr2 expression in the 10 ng/mL FSH treatment group at 2 h, 4 h and 10 h was significantly lower. Importantly, the expression level of bmpr2 and gdf9 in the 100 IU/mL hCG group had similar changes that were significantly decreased at 4 h and 10 h. In summary, Bmpr2 might play a pivotal role in ovarian growth in the ricefield eel, and these results provide a better understanding of the function of bmpr2 in ovarian development and the basic data for further exploration of the regulatory mechanism of gdf9 in oocyte development.  相似文献   
157.
Panicle traits are important factors affecting yield, and their improvement has long been a critical goal in foxtail millet breeding. In order to understand the genetic basis of panicle formation, a large-scale genome-wide association study (GWAS) was performed in this study for six panicle-related traits based on 706,646 high-polymorphism SNP loci in 407 accessions. As a result, 87 quantitative trait loci (QTL) regions with a physical distance of less than 100 kb were detected to be associated with these traits in three environments. Among them, 27 core regions were stably detected in at least two environments. Based on rice–foxtail millet homologous comparison, expression, and haplotype analysis, 27 high-confidence candidate genes in the QTL regions, such as Si3g11200 (OsDER1), Si1g27910 (OsMADS6), Si7g27560 (GS5), etc., affected panicle-related traits by involving multiple plant growth regulator pathways, a photoperiod response, as well as panicle and grain development. Most of these genes showed multiple effects on different panicle-related traits, such as Si3g11200 affecting all six traits. In summary, this study clarified a strategy based on the integration of GWAS, a homologous comparison, and haplotype analysis to discover the genomic regions and candidate genes for important traits in foxtail millet. The detected QTL regions and candidate genes could be further used for gene clone and marker-assisted selection in foxtail millet breeding.  相似文献   
158.
Asthma is a chronic respiratory disease with symptoms such as expiratory airflow narrowing and airway hyperresponsiveness (AHR). Millions of people suffer from asthma and are at risk of life-threatening conditions. Lactoferrin (LF) is a glycoprotein with multiple physiological functions, including antioxidant, anti-inflammatory, antimicrobial, and antitumoral activities. LF has been shown to function in immunoregulatory activities in ovalbumin (OVA)-induced delayed type hypersensitivity (DTH) in mice. Hence, the purpose of this study was to investigate the roles of LF in AHR and the functions of dendritic cells (DCs) and Th2-related responses in asthma. Twenty 8-week-old male BALB/c mice were divided into normal control (NC), ovalbumin (OVA)-sensitized, and OVA-sensitized with low dose of LF (100 mg/kg) or high dose of LF (300 mg/kg) treatment groups. The mice were challenged by intranasal instillation with 5% OVA on the 21st to 27th day after the start of the sensitization period. The AHR, cytokines in bronchoalveolar lavage fluid, and pulmonary histology of each mouse were measured. Serum OVA-specific IgE and IgG1 and OVA-specific splenocyte responses were further detected. The results showed that LF exhibited protective effects in ameliorating AHR, as well as lung inflammation and damage, in reducing the expression of Th2 cytokines and the secretion of allergen-specific antibodies, in influencing the functions of DCs, and in decreasing the level of Th2 immune responses in a BALB/c mouse model of OVA-induced allergic asthma. Importantly, we demonstrated that LF has practical application in reducing DC-induced Th2 cell responses in asthma. In conclusion, LF exhibits anti-inflammation and immunoregulation activities in OVA-induced allergic asthma. These results suggest that LF may act as a supplement to prevent asthma-induced lung injury and provide an additional agent for reducing asthma severity.  相似文献   
159.
Membrane proteins play important roles in biological functions, with accompanying allosteric structure changes. Understanding intramolecular dynamics helps elucidate catalytic mechanisms and develop new drugs. In contrast to the various technologies for structural analysis, methods for analyzing intramolecular dynamics are limited. Single-molecule measurements using optical microscopy have been widely used for kinetic analysis. Recently, improvements in detectors and image analysis technology have made it possible to use single-molecule determination methods using X-rays and electron beams, such as diffracted X-ray tracking (DXT), X-ray free electron laser (XFEL) imaging, and cryo-electron microscopy (cryo-EM). High-speed atomic force microscopy (HS-AFM) is a scanning probe microscope that can capture the structural dynamics of biomolecules in real time at the single-molecule level. Time-resolved techniques also facilitate an understanding of real-time intramolecular processes during chemical reactions. In this review, recent advances in membrane protein dynamics visualization techniques were presented.  相似文献   
160.
Due to the rapid development of the miniaturization and portability of electronic devices, the demand for polymer composites with high thermal conductivity and mechanical flexibility has significantly increased. A carbon nanotube (CNT)-graphene (Gr)/polydimethylsiloxane (PDMS) composite with excellent thermal conductivity and mechanical flexibility is prepared by ultrasonic-assisted forced infiltration (UAFI). When the mass ratio of CNT and Gr reaches 3:1, the thermal conductivity of the CNT-Gr(3:1)/PDMS composite is 4.641 W/(m·K), which is 1619% higher than that of a pure PDMS matrix. In addition, the CNT-Gr(3:1)/PDMS composite also has excellent mechanical properties. The tensile strength and elongation at break of CNT-Gr(3:1)/PDMS composites are 3.29 MPa and 29.40%, respectively. The CNT-Gr/PDMS composite also shows good performance in terms of electromagnetic shielding and thermal stability. The PDMS composites have great potential in the thermal management of electronic devices.  相似文献   
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