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1.
观察大豆黄酮对D 半乳糖致衰老小鼠脑的抗衰老作用.连续背部注射D 半乳糖6 周,造衰老模型,然后灌胃大豆黄酮5周(实验组Ⅰ,Ⅱ的剂量分别为10,5 mg·kg-1·d-1),取脑测定脑组织中谷胱苷肽过氧化物酶(GSH Px)、一氧化氮合酶(NOS)、单胺氧化酶(MAO)的活性.结果显示:与衰老对照组相比,实验组Ⅰ,Ⅱ的NOS,GSH Px活性均有提高,而MAO含量降低.表明大豆黄酮能增强衰老小鼠脑的抗氧化作用,提高其学习记忆能力.  相似文献   

2.
以昆明种小鼠为实验动物,采用学习记忆行为训练和生化测定相结合的方法,探讨了益智仁水提取物对D-半乳糖诱导脑老化小鼠学习记忆能力的影响.结果表明:益智仁水提取物可显著改善脑老化小鼠的学习记忆能力,其作用机制可能与益智仁的抗氧化作用有关.  相似文献   

3.
以昆明种小鼠为研究对象,利用跳台实验、旷场实验和免疫印迹杂交等方法研究了肝源性磷脂对于增强小鼠学习记忆和空间探索能力的影响.结果表明:与对照组相比,预先给予高剂量肝磷脂补充可以显著提高小鼠的学习记忆以及空间探索能力;Western Blot结果显示,与正常组相比高剂量肝磷脂补充组小鼠脑内海马区Caveolin-1和PKCα蛋白的表达量明显升高.结果提示,肝源性磷脂可以通过激活Caveolin-1蛋白和PKCα蛋白的表达增强小鼠的学习和记忆能力.  相似文献   

4.
观察不同月龄APP(amyloid precursor protein)转基因模型小鼠学习记忆功能的改变,以及中药有效部位淫羊藿黄酮对10月龄转基因小鼠学习记忆功能和脑内APP、BACE的表达及β-淀粉样肽(β-amyloid,Aβ)生成及含量的影响.用药组小鼠自4月龄开始灌胃给予淫羊藿黄酮小(0.03 g·kg-1/d)、大剂量(0.1 g·kg-1/d)6个月至10月龄,正常对照组、转基因阴性对照组及模型组以同样方式灌胃给予蒸馏水.应用Morris水迷宫和物体识别方法测试小鼠学习记忆能力,应用免疫组化学及Western Blot方法分别检测海马CA1区及皮层中APP、BACE的表达,采用双抗体夹心ELISA试剂盒测定海马中不溶性Aβ1-42含量.研究结果表明,APP转基因小鼠在4月龄即出现学习记忆能力障碍,在水迷宫实验中,比转基因阴性对照组小鼠潜伏期延长28%(p<0.05).增龄至10月龄,APP转基因小鼠学习记忆能力明显下降,水迷宫潜伏期及游泳距离与转基因阴性对照组的差异分别加大为40%(p<0.01)和35%(p<0.05),物体识别实验中分辨指数的差异为61%(p<0.05).与正常对照组及转基因阴性对照组相比,10月龄转基因模型小鼠海马CA1区及皮层中APP和BACE的表达明显增加,海马中Aβ1-42的含量明显升高.淫羊藿黄酮大剂量可明显改善10月龄APP转基因小鼠Morris水迷宫作业成绩,提高模型鼠物体识别能力,明显减少APP转基因模型小鼠海马和皮层APP及BACE的表达,降低海马Aβ1-42的含量.提示淫羊藿黄酮能改善APP转基因模型小鼠学习记忆能力和减少Aβ经由淀粉源途径生成及含量,对防治AD等神经退行性疾病具有良好的应用前景.  相似文献   

5.
大豆黄酮对衰老小鼠脑组织抗氧化能力的影响   总被引:1,自引:1,他引:1  
用大豆黄酮(daidzein)灌喂脑老化模型小鼠.5周后分别测定各组小鼠脑组织的超氧化物歧化酶(SOD)活性、乳酸脱氢酶(LDH)活性、总抗氧化能力(T-AOC)和丙二醛(MDA)含量.结果显示:大豆黄酮能够使脑老化模型小鼠的SoD的活力和T-AOC显增加,LDH的活力和MDA的含量极显下降,其中T-AOC和MDA超过了生理盐水对照组,暗示大豆黄酮除了通过提高SOD的活性来增加机体抗氧化能力外,还存在通过其他的途径来提高机体的抗氧化能力,并且大豆黄酮在抗氧化水平上还有一定的剂量效应.  相似文献   

6.
目的探讨远志皂苷和茯苓多糖(Polygala saponins and pachymaran,PSP)对记忆障碍模型小鼠空间学习记忆能力改善作用及作用机制.方法 Morris水迷宫法研究PSP对戊巴比妥钠制造的空间方向辨别障碍模型小鼠空间学习记忆能力改善作用,并测定脑组织单胺氧化酶(MAO)活性.结果 PSP能增加模型小鼠在定位航行实验中1 min内穿越安全平台次数,并缩短模型小鼠在定位航行实验中找到安全平台的逃避潜伏期;PSP能缩短模型小鼠在空间探索实验中第一次到达安全平台的时间,并增加穿越原平台的次数;PSP可以降低小鼠脑组织MAO活性.结论 PSP对模型小鼠空间学习记忆有明显的改善作用,其机制可能与降低脑组织中MAO活性有关.  相似文献   

7.
目的观察远志、茯苓煎剂(Polygala tenuifolia and Poria cocos decoction,DPP)对戊巴比妥钠所致空间方向辨别障碍模型小鼠行为学的影响,并探讨其可能的作用机制.方法应用Morris水迷宫观察DPP对戊巴比妥钠所致的空间方向辨别障碍模型小鼠的影响,并测定其血清乙酰胆碱酯酶的含量.结果 DPP能缩短模型小鼠在定位航行实验中找到平台的潜伏期;缩短在空间探索实验中第一次到达平台的时间,并增加穿越平台的次数;DPP还能有效降低模型小鼠血清中乙酰胆碱酯酶的含量.结论 DPP能改善戊巴比妥钠所致的小鼠空间方向辨别障碍,改善空间方向辨别障碍小鼠的学习记忆能力;DPP可降低小鼠脑内乙酰胆碱酯酶活性,提示其可能通过抑制胆碱酯酶提高脑内乙酰胆碱水平而发挥改善学习记忆的作用.  相似文献   

8.
研究大豆黄酮对D–半乳糖致衰老小鼠脑组织氧化损伤程度的调节.连续背部注射D–半乳糖6周,造衰老模型,然后灌胃大豆黄酮5周(实验组Ⅰ、Ⅱ的剂量分别为5、10,mg/(kg.d)),监测小鼠Y–迷宫记忆、活性氧、丙二醛、脂褐质、8–羟基脱氧鸟嘌呤和不同脑区突触素含量变化,探讨大豆黄酮对衰老小鼠脑组织氧化损伤程度的影响.结果表明,灌胃衰老小鼠大豆黄酮后,Y–迷宫学习记忆能力和大脑皮质突触素含量显著提高,同时脑组织中活性氧、丙二醛、8–羟基脱氧鸟嘌呤和脂褐质含量明显下降.与衰老对照组相比,大脑皮质和海马中的活性氧和8–羟基脱氧鸟嘌呤、脑组织中丙二醛和脂褐质含量降低程度与灌胃剂量具有正相关性.表明大豆黄酮能够提高衰老小鼠学习能力,降低衰老小鼠脑组织氧化损伤程度,具有显著的抗衰老作用.  相似文献   

9.
饮食限制58d对小鼠学习记忆及抗氧化能力的影响   总被引:1,自引:0,他引:1  
采用行为观察和生化检测方法,研究了饮食限制58 d对小鼠学习记忆的影响及其各组织中超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量的变化.结果显示:限食小鼠在新环境中更显得不安,66.7%饮食限制组小鼠记忆能力最弱而空间识别能力最强4,0%饮食限制组小鼠学习能力最强;限食小鼠各器官的脏器系数相比自由饮食组都有所升高;各组小鼠所测器官的SOD活性没有明显的区别,但心、肾和脑中MDA含量随饮食限制水平的升高而增高.提示饮食限制对机体器官有一定的损伤作用,适当饮食限制能提高学习能力,但对抗氧化能力的影响不明显.  相似文献   

10.
印防己毒素(picrotoxin, PTX)常用于研究衰老相关疾病.为探讨PTX对中年雌雄小鼠焦虑水平及学习记忆能力的影响,以8~11月龄的C57BL/6小鼠为研究对象,实验分为雌雄PTX实验组、雌雄生理盐水对照组.实验前30 min注射PTX(0.18 mg/kg),之后采用旷场、Y迷宫、Morris水迷宫实验等范式检测小鼠焦虑水平及学习记忆能力.旷场实验显示PTX显著降低了雄性小鼠在中心区的停留时间,即增加了雄性小鼠的焦虑样行为;Y迷宫实验显示PTX增加了雌性小鼠在新异臂的探索时间和次数,即增加了雌性小鼠的空间识别记忆能力;Morris水迷宫实验显示PTX降低了雌性小鼠的逃逸潜伏期并增加了其在目标象限的探索次数,即增加了雌性小鼠的空间记忆能力.长期注射PTX后Y迷宫实验显示,PTX增强了雌雄小鼠在新异臂的探索距离,即增强了雌雄小鼠的空间识别记忆能力.这些结果表明PTX能够增强雌性小鼠的空间记忆能力,但会影响雄性小鼠的活动能力及引起焦虑,PTX长期注射能够改善雄性小鼠的空间记忆能力.  相似文献   

11.
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   

12.
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   

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

14.
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   

15.
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   

16.
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   

17.
18.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

19.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

20.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

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