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1.
以白粒小麦川麦107为对照,将蓝、紫粒小麦籽粒蛋白营养与黄酮粗提物对猪油的抗氧化性进行研究.结果表明:参试蓝、紫粒小麦籽粒的蛋白含量、蛋白质氨基酸总量,非必需氨基酸和必需氨基酸含量都高于白粒对照小麦川麦107;蓝、紫粒小麦籽粒有较高的蛋白质氨基酸评分和化学评分.蓝、紫粒小麦籽粒黄酮粗提物对猪油的抗氧化性结果表明:蓝、紫粒小麦籽粒黄酮粗提物的抗猪油氧化能力都较60%乙醇强.参试材料中,除031-1的酸败时间较川麦107稍早之外,其余4个蓝、紫粒小麦品种发生酸败的时间均比川麦107要晚.  相似文献   

2.
水稻黄酮对免疫性肝纤维化的保护作用   总被引:2,自引:0,他引:2  
目的:观察水稻黄酮对免疫性肝纤维化大鼠模型的保护作用,并从自由基的产生及清除方面探讨其机理.方法:腹腔注射异源血清诱导的大鼠肝纤维化模型,以γ-干扰素作对照,测定相应肝功和肝纤维化指标,及肝组织中GSH-PX、MDA、SOD活力.结果:γ-干扰素和水稻黄酮可显著改善肝功与肝纤维化,降低MDA含量,提高SOD、GSH-PX活力.结论:γ-干扰素和水稻黄酮,对肝纤维化有明显的抑制作用;而水稻黄酮还可显著改善肝功能,提高肝组织中自由基清除系统的功能,加强肝组织清除自由基及MDA,减轻自由基对肝组织的损害.  相似文献   

3.
采用超声波辅助法对花生壳中黄酮进行提取,研究了料液比、提取功率、提取温度及提取时间对花生壳中黄酮提取率的影响.通过单因素实验和正交试验确定了花生壳黄酮的优化提取工艺:料液比为1∶30,提取功率为100 W,35℃下浸提40 min,在此工艺下提取的花生壳中黄酮的质量分数为3.458%.  相似文献   

4.
两种黄酮抗氧化活性及降低香烟粒相自由基的应用研究   总被引:1,自引:0,他引:1  
采用电子自旋共振法、光敏化合物微生物方法,研究了葛根黄酮、竹叶黄酮的抗氧化活性,并将其应用于降低香烟烟气粒相自由基的实验.结果显示,葛根黄酮、竹叶黄酮对氮氧自由基的清除率分别为35.5%和27.5%,对单线态氧的清除率分别为7.7%~58.1%和22.6%~67.7%,平均可以降低香烟烟气中23.8%和11.6%的粒相自由基.葛根黄酮和竹叶黄酮具有较好的抗氧化活性,并对香烟烟气粒相自由基有一定的清除作用.  相似文献   

5.
不同季节与产地香椿黄酮及皂苷的含量变化   总被引:5,自引:0,他引:5  
以黄酮与皂苷含量为考察指标,研究了不同季节、不同产地和同一产地不同部位香椿黄酮与皂苷的含量变化。结果表明,香椿黄酮与皂苷含量以11月份采集的样品含量最高,分别可达到叶片干重的4.57%和2.25%,不同产地香椿黄酮与皂苷含量有明显差异,北方和中原地区黄酮与皂甘含量均大于南方的江苏、上海地区采集的样品。同一产地香椿植株不同部位的黄酮与皂苷含量也有显著差别,其中根、皮中黄酮含量较高,树根中黄酮含量为2.27%,树皮中黄酮含量为3.27%,叶柄黄酮含量低,只有0.92%。皂苷含量以根部较高,达到1.47%,而叶柄皂苷含量只有0.40%。  相似文献   

6.
玫瑰花渣中色素的研究   总被引:4,自引:0,他引:4  
本文以研究玫瑰花提取挥发油后废渣的应用为目的,介绍了废渣中有色物质二氢黄酮的鉴定方法,萃取与纯化色素的主要过程,重点研究了水、乙醇、酸度、光和温度对色素稳定性影响.说明了从玫瑰花渣中提取的色素是以二氢黄酮为主体的混合色素,是一种稳定的天然色素,有广泛的应用价值。  相似文献   

7.
松花粉黄酮提取物体外抗氧化作用的研究   总被引:1,自引:0,他引:1  
研究松花粉的体外抗氧化作用.采用还原K3Fe(CN)6法对松花粉中黄酮的还原力进行了测定,用水杨酸法研究了松花粉中黄酮的清除·OH的效果,采用邻苯三酚自氧化法研究松花粉黄酮提取物对超氧阴离子自由基的清除能力,以及研究了松花粉黄酮提取物对Fe2+诱发卵黄低密度脂蛋白多不饱和脂肪酸(PUFA)过氧化反应的抑制作用.结论是松花粉中黄酮的含量为2.95‰;松花粉黄酮在体外有较好的还原力和清除羟自由基的能力;对碱性邻苯三酚自氧化产生的超氧阴离子、Fenton反应产生的羟基自由基和Fe2+诱发卵黄低密度脂蛋白多不饱和脂肪酸(PUFA)过氧化产生的烷氧基(LO·)和烷过氧基(LOO·)均有明显的抑制作用,且均呈现一定的量效关系.上述结论说明了松花粉黄酮提取物具有良好的体外氧化的作用.  相似文献   

8.
将甜荞、苦荞粉碎后乙醇浸提法提取黄酮类化合物,其黄酮粗提物的得率分别为1.39%和2.76%,粗提物中黄酮含量分别为0.589%和3.22%.以BHT和Vc为阳性对照,研究两种荞麦黄酮粗提物对植物油和动物油的抗氧化效果.结果表明,两种荞麦黄酮粗提物具有显著的抗氧化性能,其中苦荞黄酮粗提物在两种油脂中的抗氧化性高于BHT和Vc.  相似文献   

9.
黄酮化合物是许多天然药物的活性成分,由于黄酮化合物具有显著的抗癌作用而受到越来越多的重视。该文综述近了十年来国内外学者报道的47个黄酮化合物在抗癌活性中的应用研究。  相似文献   

10.
不同营养部位、树龄银杏叶黄酮含量的比较   总被引:4,自引:0,他引:4  
对银杏不同营养部位、树龄的叶黄酮含量的测定结果表明:不同营养部位叶黄酮含量的变化规律为长枝>中短枝>树冠>短枝,枝条上部叶>中部叶>下部叶,长枝上的叶黄酮含量为顶部叶>中部叶>基部叶,树冠上、中、下部叶黄酮含量呈现高-中-低的变化规律。不同树龄的银杏叶黄酮含量随树龄的增长呈递减趋势,尤其是15年以上成年大树黄酮含量下降的更加明显,几乎是幼龄小树的1/2。同时还对不同时期的银杏叶黄酮含量进行了测定,结果表明,银杏叶黄酮含量以10月份最高。因此,以叶用栽培为目的的银杏,应以10月份采摘为宜。  相似文献   

11.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

12.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to  相似文献   

15.
Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications (up to 574.8 km/ h test speeds or 380 km/h commercial speeds) in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.  相似文献   

16.
17.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.  相似文献   

19.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

20.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

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