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1.
目的 研究频率为2.2MHz的聚焦超声结合血卟啉对在体S180肿瘤组织的杀伤作用.方法 计算不同处理后对肿瘤组织的生长抑制作用,并通过透射电镜观察处理后不同时间段取材S180实体瘤超微结构的变化.结果 单纯血卟啉对在体S180肿瘤细胞几乎没有生长抑制作用;单纯超声对S180肿瘤组织有一定的生长抑制作用,且随着超声强度的增加,抑制效应逐渐显著,而超声结合血卟啉所产生的协同效应对S180肿瘤细胞的生长抑制作用明显高于单纯超声组,电镜下观察到超声激活血卟啉可以破坏肿瘤细胞的超微结构,尤其是对肿瘤细胞膜和膜性细胞器的通透性和结构的损伤,并且随着取材时间的延长,损伤效应进一步加强.结论 超声结合血卟啉能有效地抑制S180肿瘤的生长作用.  相似文献   

2.
用水提醇沉法提取夹竹桃叶多糖(NP),观察其对小鼠S180皮下移植瘤和S180腹水瘤的生长抑制作用,采用免疫组化法检测了移植瘤组织中PCNA、bcl-2、bax蛋白表达的变化,采用药物相互作用指数研究了NP与环磷酰胺联用对S180移植瘤的协同抑制作用.苯酚-硫酸法测定结果表明,提取物中的多糖质量分数为81.14%.NP对小鼠S180移植瘤有显著的抑制作用并且能延长腹水瘤小鼠的寿命,50,100,150 mg/kg剂量组的抑瘤率分别为40.00%,50.83%,44.17%,生命延长率分别为42.86%,64.29%,43.88%.NP作用后瘤组织中PCNA、bcl-2细胞的阳性率显著降低,bax细胞的阳性率显著升高,NP与环磷酰胺有一定的协同效应.  相似文献   

3.
观察穿心莲内酯对小鼠移植性肿瘤S180生长的抑制作用,并探讨其可能的机制.采用MTT法检测穿心莲内酯对体外培养的S180细胞增殖的抑制作用;建立小鼠移植瘤模型,采用荷瘤小鼠抑瘤率检测穿心莲内酯对小鼠肉瘤S180的体内抗肿瘤作用.以对荷瘤小鼠免疫器官质量,巨噬细胞对中性红的吞噬率,巨噬细胞产生TNF-α的影响评价穿心莲内酯对小鼠免疫功能的作用.结果穿心莲内酯能够剂量依赖型的抑制体外培养的S180细胞的增殖;25、50 mg/kg的穿心莲内酯对移植性动物肿瘤S180的抑瘤率分别为45.27%和56.87%,对荷瘤小鼠脾脏和胸腺质量无明显的影响.经穿心莲内酯刺激后,小鼠巨噬细胞对中性红的吞噬功能明显地增强,并能显著刺激巨噬细胞分泌TNF-α.说明穿心莲内酯具有明显的体内抗肿瘤作用,其抗肿瘤活性是通过抑制肿瘤细胞的生长,激活小鼠巨噬细胞两方面共同产生的.  相似文献   

4.
探讨半枝莲多糖对体内S180肉瘤肿瘤抑制作用及相关机制.采用动物移植性肿瘤实验观察半枝莲多糖对小鼠体内肿瘤细胞生长的影响,ELISA法检测对荷瘤小鼠外周血血清中白细胞介素-2和干扰素-α质量浓度的影响.结果显示,半枝莲多糖对S180肉瘤生长的抑制率以中剂量为佳;各剂量组均对脾脏指数有显著性差异,能够提高S180荷瘤小鼠外周血血清中白细胞介素-2及干扰素-α的质量浓度,但中剂量最为显著,表明半枝莲多糖在小鼠体内具有抑制S180肉瘤的作用.  相似文献   

5.
初步观察垂盆草不同提取物的抗肿瘤药效。采用小鼠S180肉瘤模型及小鼠S180腹水癌模型,分别用垂盆草水提物、垂盆草醇提物灌胃给药,连续8天,测定腹水瘤小鼠的生命延长率及实体瘤小鼠的瘤重。实验结果显示,垂盆草水提物、垂盆草醇提物对小鼠S180肉瘤的生长有明显抑制作用,肿瘤重量明显减轻。对小鼠S180腹水瘤小鼠生存天数亦有明显延长作用。说明垂盆草对小鼠移植性肿瘤具有抑制作用,为进行临床应用和深入的基础研究提供了依据。  相似文献   

6.
拟黑多刺蚁体外抑瘤作用研究   总被引:3,自引:0,他引:3  
目的 通过拟黑多刺蚁对体外S180 ,H2 2 ,YAC 1肿瘤细胞DNA合成影响及细胞毒性作用 ,研究该蚁抑瘤效应及机制 .方法 采用3H TdR掺入法和12 5I UdR释放法 .结果 拟黑多刺蚁对S180 ,H2 2 ,YAC 1肿瘤细胞DNA合成均有明显抑制作用 (P <0 .0 5 ) ,其抑制作用随剂量增加而增强 .以对S180 肿瘤细胞抑制作用最显著 .同时证实 ,该蚁对YAC 1,S180 肿瘤细胞均有毒性作用 .结论 拟黑多刺蚁对肿瘤细胞具有直接杀伤和抑制生长的作用 .  相似文献   

7.
甘肃猫儿眼提取物对S180瘤株毒性作用   总被引:1,自引:0,他引:1  
给予S180荷瘤小鼠不同剂量的甘肃猫儿眼提取物后,对瘤体、胸腺和脾脏重量以及对荷瘤小鼠免疫功能的影响进行测定分析。结果为,给予甘肃猫儿眼提取物20.0g/kg体质量/d,po,10d后测定,甘肃猫儿眼提取物对S180生长抑制率为42%;对小鼠碳粒廓清指数、免疫器官的重量、血清溶血素值增高等均有促进作用,组织病理学观察,给药组S180瘤体均见坏死灶,坏死面积与给药剂量呈正相关。提示,甘肃猫儿眼提取物对8180细胞增殖具有明显的抑制作用,其作用机制与提高荷瘤小鼠免疫功能有关.  相似文献   

8.
仙芦抗癌胶囊抗肿瘤作用及其作用机制研究   总被引:1,自引:2,他引:1  
通过观察仙芦抗癌胶囊对S180A和H22荷瘤小鼠瘤重和生存时间的影响,观察其体内抗肿瘤作用.采用荧光探针DPH法,观察仙芦抗癌胶囊对S180A和H22荷瘤小鼠红细胞膜流动性的影响.实验结果发现仙芦抗癌胶囊(1g/kg,0 5g/kg,0 25g/kg)对S180A小鼠的瘤体生长有显著的抑制作用.仙芦抗癌胶囊(1g/kg,0 5g/kg)对H22小鼠的生存时间有显著的延长作用.仙芦抗癌胶囊高、中、低剂量(1g/kg,0 5g/kg,0 25g/kg)均能够升高S180小鼠红细胞膜流动性.仙芦抗癌胶囊高、中剂量(1g/kg,0 5g/kg)均能够降低H22小鼠红细胞膜流动性,而低剂量组无明显作用.因此仙芦抗癌胶囊对S180A和H22都有显著的抑制作用,抗肿瘤作用机制与其恢复荷瘤小鼠红细胞膜流动性有关.  相似文献   

9.
马齿苋多糖的抗肿瘤活性   总被引:49,自引:4,他引:49  
研究了马齿苋多糖的抗肿瘤活性。结果表明马齿苋多糖可使小鼠T淋巴细胞数量增加,体外对肝癌细胞SMMC7721的增殖具有一定的抑制作用,体内可使小鼠S180腹水瘤分裂指数显著下降,并能明显抑制小鼠S180移植性实体瘤生长。  相似文献   

10.
摘要: 目的探讨化胃舒颗粒对小鼠移植性肿瘤的抑制作用。方法以S180 肉瘤和H22 肝癌作为实验瘤株,观察化胃 舒颗粒对S180 小鼠肉瘤的抑瘤率及对H22 肿瘤小鼠生存期的影响。采用小鼠移植性肿瘤S180 实体瘤模型,观察化胃舒 颗粒与环磷酰胺( CTX) 联用对S180 实体瘤小鼠的白细胞数及抑瘤率的影响。结果化胃舒颗粒能阻止S180 肿瘤生长, 小鼠肿瘤抑制率在30%以上; 化胃舒颗粒能明显延长H22 肿瘤小鼠的生存时间; 化胃舒颗粒能抑制由环磷酰胺( CTX) 引 起的S180 实体瘤小鼠血液中白细胞总数的减少,从而增强环磷酰胺( CTX) 的抑瘤作用。结论化胃舒颗粒对S180 肉瘤 和H22 肝癌荷瘤小鼠有明显的抗肿瘤作用,与环磷酰胺( CTX) 合用有显著的减毒增效作用。  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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