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1.
目的探究快速、有效地建立进展性动脉粥样硬化兔模型的方法。方法15只新西兰大耳白兔随机分为颈总动脉球囊损伤组(n=8)和假手术组(n=7),两组均饲喂高脂饮食,14周后结束实验,对颈总动脉和其他血管节段(胸主动脉、主动脉根部和腹主动脉)作病理观察,计算内膜增生面积/内弹力膜围绕面积(%)、平均内膜厚度/内弹力膜围绕面积半径(%)和最大内膜厚度/内弹力膜围绕面积半径(%),以评价斑块大小;确定病变组织形态学分型(美国心脏协会推荐)以评价斑块病变严重程度。测定实验前后的动物血脂水平。结果高脂喂养14周,在兔主动脉各血管节段中,斑块尺寸由大到小顺序:胸主动脉〉主动脉根部〉腹主动脉。胸主动脉虽在单纯高脂作用的各血管节段中斑块尺寸最大、病变进展最快,但仍主要停留在以内膜细胞外脂质池出现为特点的过渡性病变,较少发展至以脂质核心形成为特征的进展性病变。球囊损伤术使病变最轻微、进展最缓慢的颈总动脉斑块尺寸明显超过胸主动脉(P〈0.01),并使其发展为进展性动脉粥样硬化病。结论在高脂饮食基础上,球囊损伤法能够快速、有效地建立以脂质核心形成为特征的进展性动脉粥样硬化病变兔模型,为进一步探究不稳定性斑块的形成机制及干预措施提供了适用的动物疾病模型。  相似文献   

2.
目的高脂饲养的雄性载脂蛋白E基因缺陷小鼠动脉粥样硬化模型的建立。方法选取8周龄雄性ApoE-/-小鼠,以C57BL/6J小鼠为对照组,高脂饲养8周后测定血清中总胆固醇、甘油三酯、高密度胆固醇脂蛋白、低密度胆固醇脂蛋白含量;小鼠心脏主动脉根部石蜡切片,常规HE染色,观察和测量动脉粥样硬化斑块的组织学特点及病变面积。结果ApoE-/-小鼠血清中总胆固醇、甘油三酯和低密度脂蛋白胆固醇的含量显著高于同年龄同性别C57BL/6J小鼠,高密度脂蛋白的含量显著低于同龄同性别C57BL/6J小鼠;高脂饲养下16周龄ApoE-/-小鼠主动脉根部切面可见明显的脂质斑块。结论在该浓度的高脂饲料饲养条件下,ApoE-/-小鼠在16周龄已形成脂质斑块,是研究动脉粥样硬化等心血管疾病较佳的动物模型。  相似文献   

3.
 通过利用复合因素制备兔动脉粥样硬化(AS)易损斑块模型,研究四妙勇安汤对AS易损斑块的影响及作用机制。随机将40只日本大耳白兔分为正常组10只,实验组30只。正常组予普通饲料,实验组利用复合因素制备兔主AS易损斑块模型,8周时实验组随机分为模型组、辛伐组、四妙组,继续予以高脂饮食;各给药组开始给药至24周取材,观察主动脉的病理形态,检测血清MCP-1、ICAM-1、CRP含量和斑块内HSP60、TNF-α、NF-κB表达。结果显示,模型组内膜明显增厚、纤维帽较薄,斑块内有大量脂质沉积和炎症细胞浸润,血清MCP-1、ICAM-1、CRP随时间延长呈上升趋势,主动脉斑块TNF-α、HSP60、NF-κB表达增加。在给药后各时间点四妙组血清MCP-1、ICAM-1水平均低于模型组(P<0.05或P<0.01),对CRP水平影响不明显。斑块内TNF-α、HSP60、NF-κB阳性面积百分比均低于模型组(P<0.01),ICAM-1 MRNA表达低于模型组(P<0.01)。由此得出,四妙勇安汤能够稳定AS易损斑块,其作用可能是通过抑制炎症反应实现的。  相似文献   

4.
本实验采用新西兰大耳白纯种家兔,喂予高脂饮食建立高脂血症及动脉粥样硬化病理模型,观察短毛五加总甙对血脂水平、动脉粥样硬化及血管脂质含量的影响.结果表明.短毛五加总甙能明显降低总胆固醇、甘油三脂,减轻动脉粥样硬化形成,减少主动脉壁脂质的含量.提示腹腔注射短毛五加总甙能延缓或防止实验性动脉粥样硬化进展.  相似文献   

5.
兔动脉粥样硬化动物模型的建立和评价   总被引:4,自引:0,他引:4  
目的探索短时间内快速建立动脉粥样硬化家兔模型的方法和评价指标。方法用高胆固醇饲料喂养法与免疫反应损伤法结合建立兔动脉粥样硬化动物模型。分别于高脂饲养前、第4周和第8周测定血甘油三脂(TG)、总胆固醇(TC)、高密度脂蛋白(HDL)和低密度脂蛋白胆固醇(LDL)的含量、丙二醛的含量(MDA)、超氧化物歧化酶(SOD)、一氧化氮(NO)、C反应蛋白(CRP),并于第8周后作形态学观察。结果饲养4周后,模型组血清中甘油三脂(TG)、总胆固醇(TC)、高密度脂蛋白(HDL)和低密度脂蛋白(LDL)的含量、丙二醛(MDA)的含量、超氧化物歧化酶(SOD)、一氧化氮(NO)、C反应蛋白(CRP)(P<0.01)等显著性升高。饲养8周后模型肉眼及光镜下均可见典型动脉粥样斑块。结论此法能短时间内建立兔动脉粥样硬化模型。  相似文献   

6.
研究益脂康对鹌鹑动脉粥样硬化模型的防治作用. 用高脂饲料(1%胆固醇,14%猪油,6%豆油,剩余加入基础饲料)喂养复制鹌鹑动脉粥样硬化模型并同时给药,观察益脂康对其血清TC,TG,LDL-c,HDL-c,VLDL-c,肝脏脂质沉积和主动脉粥样硬化斑块形成的影响. 与模型组比较,益脂康高、中、低剂量组对鹌鹑动脉粥样硬化模型的血清总胆固醇和甘油三脂的降低有显著性差异,能提高高密度脂蛋白的含量;并有抑制主动脉粥样硬化斑块形成和脂质在肝脏沉积的作用. 研究表明益脂康高、中剂量组可显著降低鹌鹑动脉粥样硬化模型的血清总胆固醇和甘油三脂,防治动脉粥样硬化的形成.  相似文献   

7.
目的:考察葛根-丹参(1:1)组方对动脉粥样硬化鹌鹑血管内皮组织的影响.方法:连续喂养高脂饲料造模同时给药,观察葛根-丹参对动脉粥样硬化鹌鹑主动脉组织脂质斑块、内皮及内膜组织的影响.结果:葛根-丹参组方配伍后,无论乙酸乙酯部位还是水提物,均能较好的减少泡沫细胞及脂质的沉积,改善内皮细胞的肿胀、变性,抑制血管内膜的增厚及巨噬细胞的数量,尤以乙酸乙酯部位作用明显.结论:葛根丹参组方配伍具有一定的减少主动脉组织脂质斑块形成,保护血管内皮细胞作用,有效地阻止AS的形成与发展.  相似文献   

8.
目的:考察葛根-丹参(1:1)组方对动脉粥样硬化鹌鹑血管内皮组织的影响. 方法: 连续喂养高脂饲料造模同时给药, 观察葛根-丹参对动脉粥样硬化鹌鹑主动脉组织脂质斑块、内皮及内膜组织的影响. 结果: 葛根-丹参组方配伍后, 无论乙酸乙酯部位还是水提物, 均能较好的减少泡沫细胞及脂质的沉积, 改善内皮细胞的肿胀、变性, 抑制血管内膜的增厚及巨噬细胞的数量, 尤以乙酸乙酯部位作用明显. 结论: 葛根丹参组方配伍具有一定的减少主动脉组织脂质斑块形成, 保护血管内皮细胞作用, 有效地阻止AS的形成与发展.  相似文献   

9.
目的通过利用复合因素制备兔主动脉粥样硬化模型,观察血管新生在实验性动脉粥样硬化斑块中所起的作用。方法随机将24只日本大耳白兔分为对照组(8只)和实验组(16只),对照组予普通饲料,实验组用大剂量高脂饲料饲喂加以免疫损伤和球囊拉伤因素饲养10周,检测血清MCP-1、TNF-α、IL-1、CRP含量;主动脉切片进行病理形态学观察,测量PA/IA、IT、IHI、FT/IMT等;免疫组化观察斑块内CD31、VEGF表达,PCR测定动脉壁VEGFmRNA相对表达量。对炎症因子、CD31、VEGFmRNA、IHI之间进行相关性分析。结果实验组炎症因子水平较对照组显著升高(P<0.05或P<0.01);主动脉斑块形成,有典型"纤维帽",PA/IA、IT、IHI明显升高(P<0.01);主动脉斑块区CD31、VEGF表达明显增加;VEGFmRNA相对表达水平增高。并且VEGFmRNA表达与TNF-α、IHI、IT/MT呈正相关(P<0.05)。结论动脉粥样硬化斑块中有大量血管新生,其对AS斑块有重要影响作用,且血管新生可能与VEGFmRNA的高表达有关。  相似文献   

10.
目的:优化叶黄素的提取工艺,并初步探讨了叶黄素对实验性高脂家兔的降脂及抗动脉粥样硬化(AS)作用。方法:采用正交设计法优化叶黄素提取工艺,高脂饲料喂养家兔建立高脂血症和动脉粥样硬化模型。使用叶黄素连续给药4周,采用试剂盒分别测定血清总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白(HDL-C)、低密度脂蛋白胆固醇(LDL-C)及门冬氨酸氨基转移酶(AST)、肌酸激酶(CK)、血浆内皮素(ET)、一氧化氮(NO)和环磷酸鸟苷(c GMP)含量,取主动脉,观察动脉斑块面积并进行病理学检查。结果:通过正交实验后得出最佳实验条件下叶黄素提取率最高可达90%以上;叶黄素高剂量组能降低家兔血清中TC、TG、LDL-C含量(P﹤0.05),升高血浆NO、c GMP水平(P﹤0.05),减少ET生成(P﹤0.05),降低主动脉粥样硬化病理变化。结论:采用超声提取可以提高叶黄素的提取效率,叶黄素通过调节血脂代谢、升高血浆NO、c GMP含量,减少ET生成等方式达到抗动脉粥样硬化的作用。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  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.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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.
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   

19.
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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