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1.
目的观察北五味子多糖(Schisandra chinensis polysaccride,SCP)抗异丙肾上腺素(Isoproterenol,ISO)诱导的心室重构作用并探讨其作用机制.方法异丙肾上腺素皮下注射致心室重构模型,经SCP低、中、高(25,50,100 mg/kg)3个剂量组和阳性对照卡托普利(50 mg/kg)治疗后,观察其对心肌病理学改变、心室重量(HW/BW)和心室重量指数(LVI)、羟脯氨酸(Hyp)含量、Ⅰ型和Ⅲ型胶原含量及Western blot技术检测心肌组织中TGF-β1表达的影响.结果 SCP不同剂量组均能降低HW/BW和LVI(P0.05或P0.01),降低羟脯氨酸含量(P0.05或P0.01)),降低心肌组织中Ⅰ型和Ⅲ型胶原含量(P0.05或P0.01或P0.001),减轻TGF-β1在心肌组织中的表达(P0.05或P0.01或P0.001),抑制心室重构.结论 SCP能够通过抑制TGF-β1的表达来对抗ISO诱导的大鼠心室重构.  相似文献   

2.
目的研究北五味子木脂素(Schisandra lignans,SCL)和北五味子粗多糖(Schisandra chinensis polysaccharides,SCP)对异丙肾上腺素(Isoproterenol,ISO)诱导小鼠心室重构的保护作用,并探讨其初步机制.方法采用连续10 d皮下注射ISO的方法诱导小鼠心室重构模型.小鼠随机分为对照组、ISO组、SCL低、中、高3个剂量组和SCP组,采用灌胃给药方法.实验结束后计算小鼠心脏重量指数;观察心肌病理形态学改变情况;HE染色后测定心肌纤维直径(MD);分光光度法测定心肌组织中羟脯氨酸(HYP)含量、一氧化氮(NO)含量、一氧化氮合酶(NOS)活性、超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量.结果与对照组相比,ISO组小鼠心脏重量指数、HYP含量和MDA水平明显升高(P0.05或P0.01),NOS和SOD活性及NO水平明显下降(P0.05或P0.01);与异丙肾上腺素组相比,北五味子木脂素和北五味子多糖组能明显降低心脏重量指数(P0.05或P0.01),改善心肌病理学变化,抑制心肌组织中羟脯氨酸含量,提高SOD活性,降低MDA含量,提高心肌中NOS活性和NO水平(P0.05,P0.01或P0.001).结论北五味子木脂素和北五味子多糖对ISO诱导的小鼠心室重构具有抑制作用,其机制可能与提高NOS活性和NO水平、清除氧自由基、提高机体的抗氧化能力有关.  相似文献   

3.
目的探讨参芎滴丸对异丙肾上腺素诱导大鼠心肌缺血的保护作用及其机制。方法采用异丙肾上腺素(ISO)诱导大鼠急性心肌缺血模型,观察参芎滴丸预给药5 d后对大鼠注射ISO诱导急性心肌缺血后不同时间点心电图(ECG)J点下移的影响;继续给药2 d检测各组大鼠血清中乳酸脱氢酶(LDH)、肌酸磷酸激酶(CK)和天冬氨酸转氨酶(AST)的活性;同时测定大鼠心肌组织中超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-Px)的活性和丙二醛(MDA)的含量,并观察心肌组织形态学的改变。结果参芎滴丸能明显改善ISO引起的大鼠心电图J点下移变化;降低大鼠血清中LDH、CK、AST的水平和心肌组织中的MDA含量;不同程度地升高心肌组织中的SOD、CAT的活性;明显改善ISO引起的心肌病理损伤;但对GSH-Px活性无明显影响。结论参芎滴丸对大剂量异丙肾上腺素引起的大鼠急性缺血性心肌损伤有明显的保护作用,其机制可能与提高心肌的抗氧化能力、减轻氧化应激反应有关。  相似文献   

4.
目的研究卡托普利对异丙基肾上腺素致大鼠急性心肌损伤后半乳糖凝集素-3表达的影响及其意义.方法随机将30只雄性Wistar大鼠分为异丙基肾上腺素组(Iso组)、卡托普利组(Cap灌胃组)、对照组.光学显微镜下观察心肌组织病理形态;用RT-PCR方法检测心肌组织Gal-3 mRNA表达;用Westernblot方法检测Gal-3蛋白表达.结果与对照组比较,Iso处理组心肌细胞纤维化明显,Gal-3 mRNA及Gal-3蛋白的表达升高(P0.05); Cap灌胃处理组与Iso处理组比较,心肌纤维化面积减小,Gal-3 mRNA及Gal-3蛋白的表达降低(P0.05).结论卡托普利可能通过抑制Gal-3的表达来保护心肌,减慢心室重塑,延缓心力衰竭的发生,降低心力衰竭患者的死亡率.  相似文献   

5.
目的 观察皮下注射不同天数异丙肾上腺素(1 mg/kg体质量)诱发大鼠特异性心肌病所引起心肌组织切片HE染色、VEGF(血管内皮生长因子)、FGF(成纤维细胞生长因子)表达及心电图T波的变化。方法 除空白组外各组大鼠皮下多点注射异丙肾上腺素(1 mg/kg),分别为连续皮下多点注射异丙肾上腺素(1 mg/kg)2 d组、连续皮下多点注射异丙肾上腺素(1 mg/kg)4 d组、连续皮下多点注射异丙肾上腺素(1 mg/kg)6 d组。给药1周后,大鼠麻醉,测心电图,取心脏,采用HE染色观察大鼠心肌细胞损伤程度的变化,采用免疫组化技术染色观察心肌组织切片VEGF(血管内皮生长因子)、FGF(成纤维细胞生长因子)表达的变化。结果 与空白对照组相比连续皮下多点注射异丙肾上腺素(1 mg/kg)6 d组HE染色组织切片镜下观察具有明显差异,同时随着造模时间的延长模型组心肌组织切片VEGF(血管内皮生长因子)、FGF(成纤维细胞生长因子)表达情况与空白对照组比也存在显著性差异。结论 本研究结果表明与空白对照组相比连续皮下多点注射异丙肾上腺素(1 mg/kg)6 d组模型大鼠特异性心肌病所引起的心肌组织切片HE染色、VEGF(血管内皮生长因子)、FGF(成纤维细胞生长因子)表达及心电图T波的变化具有显著性差异,因此大鼠连续皮下多点注射异丙肾上腺素(1 mg/kg)6 d可以作为特异性心肌病药效评价的实验动物模型使用。  相似文献   

6.
目的 颈部皮下注射不同剂量异丙肾上腺素(ISO)建立小鼠慢性心肌缺血模型,通过比较确定最佳造模剂量,寻求较为客观可靠的指标,为相关模型制备及药效评价提供参考。方法 3个模型组分别皮下注射ISO 32 mg/kg、16 mg/kg和8 mg/kg体质量,连续3 d,描记造模后24 h、8d和15 d心电图(ECG);第8天和第15天时分别检测各组血液心肌损伤标志物并心脏取材,观察各组心肌形态学病理变化。结果 ISO 32 mg/kg和ISO 16 mg/kg剂量组在造模后的8 d及15 d心电图T波均显著降低(P<0.05或P<0.01);心肌损伤标志物显著改变(P<0.05或P<0.01),其中ISO 32 mg/kg组产生病理改变,死亡率为42.5%,较适用于抗慢性心肌缺血药物较长期治疗给药的药效评价。ISO 16 mg/kg的剂量死亡率为25%,相对较低,并且未导致心肌病理性损伤。结论 可根据不同试验预期选择性地采用ISO 16或32 mg/kg造模剂量建立小鼠慢性心肌缺血模型。  相似文献   

7.
目的:研究桂枝茯苓丸对异丙肾上腺素诱导大鼠慢性心衰模型的影响,并初步探讨药物对AngⅡ、TGF-β相关因子的影响.方法:健康SD大鼠60只,体重180~220 g,按体质量随机分为6组,即空白对照组、模型对照组、桂枝茯苓丸1.125 g/kg剂量组、桂枝茯苓丸2.25 g/kg剂量组、桂枝茯苓丸4.5 g/kg剂量组和阳性药物对照组(普萘洛尔).建立异丙肾上腺素致大鼠慢性心衰模型,并给予相应药物治疗15 d.末次给药后12 h,麻醉后取血,分别检测血清AST、ALT、CK和LDH水平.取心脏,固定,采用免疫组化方法分别检测心肌TGF-β和AngⅡ的表达水平.结果:与模型对照组相比,桂枝茯苓丸能明显或部分降低ALT的水平(P0.05~0.01);抑制TGF-β、AngⅡ的表达(P0.01~0.05).结论:桂枝茯苓丸具有一定的减轻慢性心衰大鼠心肌损伤的作用,其心肌保护机制可能与TGF-β、AngⅡ的降低有关.  相似文献   

8.
为研究白藜芦醇(RES)对胰岛素抵抗小鼠的糖脂代谢影响及心肌的保护作用。将雄性c57bl/6小鼠随机分对照组(NC)、高脂组(H)、高脂+溶媒(C)、高脂+溶媒+RES干预组(R),分别给予相应饲料喂养14周后给予相应灌胃干预处理。8周后检测小鼠血脂、血糖、血清脂肪因子;检测心肌羟脯氨酸;采用蛋白质印迹法(western blotting,WB)检测心肌Ⅰ、Ⅲ型胶原的蛋白表达;实时荧光定量PCR、WB检测小鼠的心肌PPARγ(过氧化物酶增殖物激活受体γ)、ADPN(脂联素)、TNF-α(肿瘤坏死因子α)的mRNA及蛋白表达情况。结果表明:与NC组相比,H组与C组总胆固醇(total cholesteral,TC)、低密度脂蛋白(low density lipoprotein,LDL)升高(P0.01);血清瘦素、抵抗素水平升高;心肌中羟脯氨酸、胶原、TNF-α升高(P0.01或P0.05);PPARγ、ADPN表达下降(P0.01);而R组较H组TC、LDL降低(P0.05);血清瘦素、抵抗素水平下降;心肌中胶原、TNF-α降低(P0.01或P0.05);PPARγ、ADPN的表达升高(P0.01)。RES可能是通过激动PPARγ调节ADPN、TNF-α改善胰岛素抵抗小鼠糖脂代谢紊乱、心肌肥厚、纤维化。  相似文献   

9.
目的多种心脏疾病可引起心肌细胞Giα2含量增加,本实验研究Giα2增加的可能作用。方法:在心肌细胞上增加Giα2基因表达后,观察心肌细胞对不同浓度的异丙肾上腺素引起的收缩反应,以及对慢性高浓度异丙肾上腺素刺激引起细胞死亡的效应。结果:增加Giα2基因表达后,心肌细胞对不同浓度的异丙肾上腺素引起的收缩反应明显降低(p<0.01vs Control);增加Giα2基因表达可改善因慢性高浓度异丙肾上腺素刺激引起的细胞死亡(p<0.01vs Control)。结论:在心肌细胞中Giα2含量增加可能是一种适应性保护。  相似文献   

10.
脉瑞康大剂量对异丙肾上腺素(Isoprenaline,Isop)增加小鼠心肌耗氧有明显抑制作用,可显著延长小鼠耐缺氧存活时间(P<0.05);脉瑞康大剂量可致心肌损伤大鼠血清活性升高的天门冬氨酸氨基转换酶AST、磷酸肌酸激酶CPK显著降低(P<0.05),对活性升高的α-羟丁酸脱氢酶(α-HBDH)、乳酸脱氢酶(LDH)有一定降低作用,但无显著意义,组织病理学检查也显示心肌病理损伤减轻.  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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