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1.
应用现代方法对川黄柏中化学成分及其体外抗肿瘤作用进行研究.从川黄柏中分离鉴定了7个已知化合物,分别为小檗碱(1)、巴马汀(2)、10,11-二甲氧基-13-甲基小檗碱(3)、丁香脂素O-β-D葡萄糖苷(4)、紫丁香酚苷(5)及常见的β-谷甾醇(6)和β-胡萝卜苷(7).以HepG2、MCF7、HT29和MKN28肿瘤细胞株为研究对象,采用MTT法研究了化合物的体外抗肿瘤活性.实验结果显示化合物1和3具有较强的抑制肿瘤细胞HepG2生长的作用,IC50值分别为0.15和0.19μM.表明川黄柏中得到的化合物对不同种肿瘤细胞具有细胞毒选择性,有一定的抗癌活性.  相似文献   

2.
以邻甲基苯腈和芳香醛为原料,在强碱催化下经一步反应直接得到11,12-二氢苯并菲啶类化合物,产物再跟3芳基-3-氯-2-氧丙酸乙酸甲酯反应得到二氢苯并菲啶骈咪唑环化合物,共合成了8个目标化合物,并研究了部分目标产物的抗肿瘤活性及与牛胸腺DNA的相互作用.活性研究结果表明:一些化合物对肝癌(HepG2)、鼻咽癌(CNE)、胃癌(7901)等癌细胞具有较好的体外生长抑制活性,与小牛胸腺DNA具有较强的相互作用.  相似文献   

3.
瑞香狼毒总木脂素的体外抗肿瘤活性   总被引:1,自引:0,他引:1  
研究了瑞香狼毒总木脂素的体外抗肿瘤作用.用MTT比色分析法、集落形成法对瑞香狼毒总木脂素的体外抗肿瘤活性进行研究,并与长春新碱的活性进行了比较.瑞香狼毒总木脂素成分对肿瘤细胞株SGC-7901,HEP-7402和HL-60的增殖及克隆形成具有较强的抑制作用,其体外抗肿瘤活性高于或接近于长春新碱,证明瑞香狼毒总木脂素成分具有较强的体外抗肿瘤作用.  相似文献   

4.
以广西主产中药广豆根的抗肿瘤活性成份苦参碱为天然活性配体,与Fe(Ⅱ)反应得到黄色的离子型苦参碱Fe(Ⅱ)化合物[H-Matrine][FeCl4],用X射线单晶衍射分析其晶体结构,并通过MTT法对苦参碱配体及其Fe(Ⅱ)化合物的体外抗肿瘤活性进行研究.体外抗肿瘤活性测试结果表明,相比于苦参碱配体,化合物对肾癌7860、肝癌BEL7404、结肠癌HCT116、结肠癌LOVO、鼻咽癌CNE1等肿瘤株的抑制活性明显增强,其中对肝癌细胞BEL7404和结肠癌细胞HCT116表现出较强的抑制活性.  相似文献   

5.
基于前期计算机辅助药物研究结果,结合Lipinski类药规则,保留了氟康唑的2,4-二氟苯基、叔醇羟基和一个三唑环,合成了8个C-3连接尿嘧啶侧链的氟康唑新衍生物,并测定了其体外抗真菌活性.新衍生物结构经1H NMR、MS确证,初步体外抗真菌活性试验表明,化合物3b对新生隐球菌表现出一定的抗真菌活性.  相似文献   

6.
合成了2-吡啶甲醛缩苯二胺双Schiff碱Cd(Ⅱ)配合物,通过元素分析和IR对其结构进行了表征.采用MTT法评价配合物体外抗肿瘤细胞增殖活性,通过光谱法和粘度测定法研究生理pH条件下,配合物与DNA的相互作用.结果表明,配合物对人白血病细胞(K-562)、人肝癌细胞(SMMC-7721)、人乳腺癌细胞(MCF-7)均有较强的体外抗肿瘤细胞增殖活性,配合物以部分插入方式与DNA结合.  相似文献   

7.
在研究帕唑帕尼构效关系的基础上,以3-甲基-6-硝基吲唑为原料,设计合成4个帕唑帕尼衍生物.化合物结构经过1H NMR、LC-MS及元素分析确证,并进行体外抗肿瘤细胞增殖活性研究.采用四氮唑盐(MTT)法测试了4个化合物对MGC803细胞增殖的抑制作用.结果表明,目标化合物对于MGC803细胞增殖均有一定的抑制作用.  相似文献   

8.
研究铂(II)与三种胺类配合物的合成、晶体结构和体外抗肿瘤活性,化合物1的X-射线单晶结构分析表明:这是一个很少见的具有四方锥几何构型的铂(II)配合物,顺式平面四方形配位的铂的轴向上有第5个配位原子。其抗肿瘤活性实验显示3个配合物对几种研究的癌细胞都有较强的抑制作用。  相似文献   

9.
基于纤细薯蓣皂苷母体结构,通过水解和酯化反应制备了11个纤细薯蓣皂苷衍生物,通过波谱学方法(NMR、MS)确证了其化学结构,其中化合物Ⅰ、Ⅱ、Ⅴ、Ⅵ、Ⅸ、Ⅺ均为新化合物.采用改良MTT法对衍生物进行了体外抗肿瘤活性试验,结果显示,纤细薯蓣皂苷衍生物对人慢性骨髓性白血病细胞K562、人肝癌细胞HepG-2均表现出一定的抗肿瘤活性,一些化合物表现出优于纤细薯蓣皂苷元的抗肿瘤活性,其中的化合物Ⅸ、Ⅺ表现出明显的抗肿瘤活性趋势,尤其化合物Ⅸ,对2种肿瘤细胞的IC50值分别为3.66 μg/mL和21.47 μg/mL;而且发现糖基部分糖的数量影响化合物抑制肿瘤细胞的活性.  相似文献   

10.
概述了近几年杂多化合物在药物化学上的应用研究新进展,对杂多化合物的结构与抗肿瘤、抗病毒活性的关系及抗肿瘤、抗病毒机理进行了评述.  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.
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   

13.
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   

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.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  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.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

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