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1.
探索导管超声在活体犬心腔内辐照心肌的可行性,及辐照后对心肌组织、细胞的生物效应.研制超声辐照导管在X线影像引导下经介入法进入活体犬左心室腔,在心腔内以频率4.3 MHz、声能1w/cm2的超声照射心肌1 min;即刻观察超声照射后血流动力学、心肌组织和细胞病理形态、超微结构的变化.导管超声辐照后光镜见心肌轻微充血,电镜发现线粒体普遍轻微肿胀,毛细血管内皮细胞间隙增宽,肌浆网扩张;血流动力学检测则显示有心肌收缩增强的趋势.超声辐照导管在心腔内辐照活体心肌安全可行,具有增加细胞膜及毛细血管通透性等生物效应、并且未产生毒副效应.  相似文献   

2.
为探讨穗花杉双黄酮(Amentoflame,AF)对人脐静脉内皮细胞ECV304血管形成及机制的影响,从而为穗花杉双黄酮治疗肿瘤及其他血管增生性疾病提供理论基础,采用MTS检测AF对ECV304血管内皮细胞增殖的作用,细胞划痕实验观察AF对ECV304细胞迁移的影响,体外血管形成实验观察AF对ECV304血管形成的影响,Western blot检测AF对ECV304细胞血管形成相关信号通路及蛋白如磷酸化AKT(p-AKT)、金属基质蛋白酶9(Matrix metalloproteinase-9,MMP-9)、促血管生成素2(angiopoietin 2,Ang 2)表达影响。结果表明AF能够抑制ECV304细胞的增殖作用,并呈梯度依赖性;AF具有抑制ECV304细胞迁移的作用,并且能够抑制ECV304体外血管样结构的形成;Western blot结果显示100μmol/L的AF能够降低ECV304细胞p-AKT、MMP-9、Ang-2的蛋白表达。  相似文献   

3.
胡小勤 《科学技术与工程》2012,12(27):6883-6888
揭示补阳还五汤与高血压病气虚血瘀证"方证相关"的现代生物学基础,制作高血压病气虚血瘀证细胞模型。用补阳还五汤含药血清干预细胞模型,利用双向凝胶电泳(2-DE)及基质辅助激光解吸电离飞行时间质谱(MALDI-TOF-MS/MS)技术筛选及鉴定差异表达的蛋白点。并对其进行生物学分析。结果高血压病气虚血瘀证组与健康对照组比较,差异蛋白质点有30个。其中,有16个蛋白上调,14个蛋白质下调。补阳还五汤组与高血压病气虚血瘀证组比较,差异蛋白质点有14个。其中,有9个蛋白上调,5个蛋白质下调。MALDI-TOF-MS/MS鉴定出:高血压病气虚血瘀证组与健康对照组差异蛋白点共有8个蛋白被成功鉴定出来。表达上调的蛋白有肽基脯氨酰异构酶A、肽基脯氨酸顺反异构酶A样1亚型、真核翻译起始因子5A-1 B亚型、微管蛋白beta-2C、CRA_b亚型、3-羟酰辅酶A脱氢酶2型异构体2。表达下调的蛋白有丙酮酸激酶同工酶M1亚型、抑制蛋白-1、抑制蛋白-1 1亚型、补阳还五汤组与高血压病气虚血瘀证组差异蛋白点共有3个蛋白被成功鉴定出来。表达上调的蛋白有丙酮酸激酶CRA_c亚型、热休克蛋白27;表达下调的蛋白有膜联蛋白A1,CRA_b亚型。这些蛋白多与促进或抑制细胞凋亡有关。说明高血压病气虚血瘀证存在着细胞凋亡,补阳还五汤可以纠正高血压病气虚血瘀证引起的细胞凋亡。这些差异蛋白可以作为高血压病气虚血瘀证的标志蛋白或补阳还五汤的作用靶点,抑制细胞凋亡可能是补阳还五汤与高血压病气虚血瘀证"方证相关"的现代生物学基础之一。  相似文献   

4.
银杏叶多糖对人脐静脉内皮细胞与HL-60细胞粘附的影响   总被引:4,自引:1,他引:3  
根据人脐静脉血管内皮细胞(ECV-304)的显微和超微结构,研究了银杏叶多糖(GBLP)对ECV-304细胞和HL-60细胞粘附作用的影响.结果表明,正常生长的ECV-304细胞呈不规则形,细胞质丰富,细胞核呈圆形或椭圆形.电镜下,可见细胞表面有绒毛,细胞内具有Weibel-Palade小体.当ECV-304细胞受凝血酶(thrombin)刺激后,与HL-60细胞的粘附能力明显提高;而当用200 μg/ mL和500 μg/ mL剂量的GBLP处理ECV-304细胞后,与HL-60细胞的粘附率明显下降.这表明200 μg/ mL和500 μg/ mL剂量的GBLP对人脐静脉内皮细胞与HL-60细胞粘附有抑制作用.  相似文献   

5.
高强度聚焦超声的生物学焦域研究   总被引:5,自引:1,他引:4  
研究高强度聚焦超声(HIFU)在组织内能量的存积规律及表达方式.用JC型聚焦超声肿瘤治疗系统将超声波聚焦,辐照离体的牛肝、肾、肌肉组织和活体的猪肝、肾、肌肉组织,观察单点凝固性坏死的形成和体积变化规律.无论离体、活体组织的凝固性坏死点的形态和体积均不同于声学焦域;如果声强为7×10 3 ~25.4×10 3 W/cm 2 ,辐照时间为0~20s,则凝固性坏死点的体积为0~2000mm 3 ;同一剂量辐照下,不同组织结构、不同功能状态、不同组织深度所形成的单点凝固性坏死的体积不同.整块肿瘤的凝固是由一个一个小点状的凝固性坏死组合而成.把这个点状的凝固性坏死范围叫做HIFU的生物学焦域.生物学焦域是HIFU切除肿瘤的基本单元.它是声学焦域、声强、辐照时间、治疗深度、组织结构及功能状态的函数.  相似文献   

6.
为研究线粒体在白藜芦醇诱导人肝癌细胞系HepG2细胞凋亡中的作用机制。分离提取白藜芦醇处理的HepG2细胞及对照组细胞的线粒体蛋白质,双向电泳分离差异蛋白质,飞行时间质谱鉴定差异蛋白点,摸索并建立了一种有效分离提取细胞线粒体蛋白质和双向电泳的方法。初步分析鉴定了四个显著性差异蛋白,着丝粒蛋白Kinesin protein和CENP-E降低,证明白藜芦醇对细胞周期及细胞骨架的调节作用,Peptidase (mitochondrial processing)表达降低,线粒体核糖体蛋白L7/L12(Mitochondrial ribosomal protein L7/L12, MRP L7/L12)表达升高,表明白藜芦醇诱导HepG2细胞与其对线粒体功能的影响有关。  相似文献   

7.
本文叙述了频率1MH_2的连续,聚焦超声波强度I_(SATA)(I_(SATA)—为空间平均值,时间平均值强度,下同)为1,3,5,10,15,20w/cm~2六种强度。用其进行模拟性的体外辐照活体家兔肝脏产生的生理效应。并通过实验求得被超声辐照的肝组织损伤最小的辐照时间。经过统计处理后求得一个体外损伤的阈值曲线。这个结果对于超声在医学中的应用具有重要的实际意义。  相似文献   

8.
为探讨聚焦超声治疗对小鼠外阴上皮内瘤变的影响,研究治疗前后VEGF表达变化,采用苯甲酸雌二醇注入40只129/J型鼠腹部皮下,7周时建立外阴上皮内瘤变轻到中度不典型增生(Vulvar Interaepithelial Neoplasia,VIN Ⅰ~Ⅱ)小鼠模型.随机分为聚焦超声治疗组和假照组,治疗前后检测皮肤病理及VEGF表达变化.建立VIN Ⅰ~Ⅱ小鼠模型16例.结果显示聚焦超声治疗组7例皮肤基本恢复正常,VEGF表达降低.与假照组相比差异均有统计学意义(P<0.05).由此得出,聚焦超声治疗小鼠外阴内上皮瘤样病变具有无创性、安全性和有效性.  相似文献   

9.
利用复频聚焦超声激活血卟啉杀伤肿瘤,对不同声参量(血卟啉浓度、超声辐照时间、超声强度)进行了对比选择性试验.结果表明,血卟啉浓度为100~200μg/mL,超声辐照时间约为120s时,超声辐照强度增加.复频超声作用的效果不是单频的代数和,而是单频和的1.3~2倍.  相似文献   

10.
探讨影响大鼠血管平滑肌细胞(VSMCs)增殖的超声辐照强度和时间,分别用30、60、100、150、200W等辐照强度和10、30、60、100 s等辐照时间处理VSMCs.MTT法和细胞上清液NO含量测定法检测细胞的增殖状态.研究结果表明:超声辐照强度为30、60 W和时间为100 s时抑制细胞的增殖显著,且时间与强度之间无互作效应.  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.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
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   

15.
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   

16.
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   

17.
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   

18.
19.
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   

20.
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   

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