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1.
将小鼠的MT-I基因插入pSV2-dhfr质粒的EcoRI位点,构建了具有SV40和MT双启动子并正向插入MT-I基因的表达载体。用改良的磷酸钙/DNA沉淀法将表达载体导入CHO-dhfr-细胞内,用不含次黄嘌呤(H)和胸腺嘧啶(T) 的选择培养基筛选出稳定表达MT阳性克隆D-22,经检测106细胞的 MT 表达量约为1.8 μg,D-22细胞对Cd2+浓度抗性较之CHO-dhfr-细胞高14倍。为了研究金属硫蛋白对正常细胞所具有的保护作用,将不同浓度的顺铂分别处理无MT表达的CHO-dhfr-细胞和有MT表达的D-22细胞。实验发现顺铂对D-22细胞和CHO-dhfr-细胞 50%生长抑制浓度(IC50)分别是0.145μmol/L 和0.04μmol/L。上述研究表明MT对正常细胞有一定的保护作用,因而通过诱导正常细胞提高MT的表达量,同时使用MT阻断剂阻断肿瘤组织的MT合成,这样可能会为治疗某些顽固肿瘤开辟一条新途径。  相似文献   

2.
检测灯盏乙素对乳腺癌MDA-MB-231细胞中的长链非编码RNA(LncRNAs)的相对表达量的影响,进一步探索灯盏乙素对肿瘤的作用机制.采用实时荧光定量PCR的方法,检测对照组与不同剂量组的灯盏乙素处理后的乳腺肿瘤细胞中lncRNAs MALAT1、NEAT1和p53基因mRNA的相对表达量,并观察细胞存活率.结果发现,灯盏乙素在低剂量(1、10、25μmol/L)时促进细胞增殖,而在高剂量50μmol/L以上时抑制细胞增殖.灯盏乙素在低剂量时使得乳腺癌MDA-MB-231细胞中MALAT1,NEAT1和p53基因的表达水平下降,而在100μmol/L的高剂量时MALAT1,NEAT1和p53基因的表达水平上升.灯盏乙素影响乳腺癌MDA-MB-231细胞中LncRNAs MALAT1和NEAT1基因以及p53基因的表达,并且存在剂量反应关系,低剂量与高剂量呈现出相反的表达量变化.  相似文献   

3.
以不同浓度H_2O_2刺激PC3细胞24h,应用MTT法分析细胞活力变化,并采用蛋白印迹方法检测HSP60蛋白、Akt蛋白(总Akt蛋白)和磷酸化Akt蛋白的表达水平.结果表明,15.625μmol/L的H2O2可诱导PC3细胞内HSP60表达显著升高(p0.05),7.312μmol/L和15.625μmol/L的H_2O_2均会导致磷酸化Akt蛋白的量显著下降(p0.01),但该两种浓度的刺激对细胞内总Akt蛋白量并无显著影响(p0.05).  相似文献   

4.
金属硫蛋白对细胞的环境应激起到重要的调节作用,在重金属离子胁迫下上调表达。然而其具体的表达调节机制并不清楚。本研究从嗜热四膜虫克隆了锌指蛋白基因ZFP1(TTHERM-01002770),ZFP1基因无内含子,全长2 160bp,编码719aa。构建了ZFP1敲除载体pN-ZFP1,通过同源重组的方法敲除ZFP1基因获得ZFP1敲除的突变细胞。ΔZFP1对Cu2+和Cd2+的EC50值分别为53.0μmol/L和25.3μmol/L,低于野生型细胞83.1μmol/L和32.8μmol/L.Cu2+胁迫下,ΔZFP1突变细胞中MTT2、MTT3、MTT4和MTT5的转录水平降低,MTT1转录水平上调;Cd2+诱导下,MTT4转录水平降低,MTT1、MTT2、MTT3和MTT5的转录水平上调,敲除ZFP1基因影响了细胞对Cu2+和Cd2+的耐受性,ZFP1的缺失导致Cu2+和Cd2+诱导下金属硫蛋白基因转录水平变化。结果表明Zfp1参与了金属离子胁迫下嗜热四膜虫金属硫蛋白基因的表达水平。  相似文献   

5.
Wangzaozin A调节NADPH氧化酶源性活性氧诱导HL-60细胞分化   总被引:2,自引:0,他引:2  
利用台盼蓝排染法、吉姆萨染色及流式细胞术对对映-贝壳杉烷二萜wangzaozin A影响人早幼粒白血病细胞HL-60生长、细胞形态、NBT还原能力、细胞吞噬及细胞表面抗原CD11b表达进行了检测.结果显示,0.2~0.8μmol/L wangzaozin A抑制HL-60细胞生长,0.6和0.8μmol/L处理组细胞显示了明显的G1期周期阻滞.随着wangzaozin A浓度升高及处理时间延长,细胞核质比减小,肾形核、杆状核和分叶核细胞增多及胞质中颗粒状物质增加;同时,细胞NBT还原能力、吞噬能力及细胞表面抗原CD11b表达显著增强,表明wangzaozin A可诱导HL-60细胞向成熟粒细胞分化.进一步利用荧光探针DCF检测显示0.6和0.8μmol/L wangzaozin A处理细胞12h后细胞内ROS显著升高;抗氧化剂NAC及NADPH氧化酶抑制剂APO显著抑制wangzaozin A诱导HL-60细胞上调CD11b表达,表明wangzaozin A可通过上调NADPH氧化酶源性的活性氧浓度诱导HL-60细胞分化.  相似文献   

6.
为研究接骨草成分之一绿原酸(CGA)对成骨细胞MC3T3-E1活性的影响,采用MTT法检测11.02,22.05,44.09,88.19μmol/L CGA对成骨细胞增殖率,碱性磷酸酶(ALP)试剂盒检测成骨细胞ALP活性,实时定量PCR检测成骨细胞骨相关基因的表达.结果表明:11.02~88.19μmol/L CGA对成骨细胞增殖具有明显的促进作用.培养2d,44.09μmol/L CGA能促进ALP表达上调;22.05,44.09μmol/L CGA能促进ALP、Runx2、Osterix、c-jun和c-fos基因的表达;培养6 d,44.09μmol/L CGA能促进c-fos基因的表达;在整个培养过程中,I型胶原(Col-I)基因的表达具有浓度和时间依赖性.故CGA具有一定的成骨活性,是接骨草的成骨活性成分之一.  相似文献   

7.
采用体外培养人胚肺成纤维细胞(HFL-I)的方法,应用qPCR技术检测全反式维甲酸(ATRA)对转化生长因子-β1(TGF-β1)诱导人胚肺成纤维细胞中α-SMA基因表达的影响.实验分为正常对照组、5μg/L TGF-β1组、10μmol/L ATRA组、5μg/L TGF-β1+0.1μmol/L ATRA组、5μg/L TGF-β1+1μmol/L ATRA组和5μg/L TGF-β1+10μmol/L ATRA组(TGF-β1和ATRA同时加入).处理24h后检测结果显示:与对照组细胞相比,TGF-β1诱导HFL-I中α-SMA基因表达明显上调(6.36倍).不同浓度ATRA干预后均可以明显抑制TGF-β1诱导的HFL-I中α-SMA基因表达(分别为正常组的3.89、1.94和1.42倍).以上结果表明,ATRA可以明显抑制TGF-β1诱导的α-SMA基因表达.ATRA对HFL-I细胞增殖和TGF-β1诱导分化的抑制作用可能是通过下调α-SMA基因表达实现的.  相似文献   

8.
目的:通过建立体外肝细胞株LO-2脂肪变性模型,初步探究细胞珠蛋白对非酒精性脂肪肝中脂质沉积、炎性因子表达及NF-κB通路的影响及相关分子机制.方法:通过含有浓度200μmol/L油酸、100μmol/L棕榈酸的高脂培养基诱导人正常肝细胞株LO-2脂肪沉积,以LO-2-GFP-CYGB为实验组,LO-2-GFP为对照组探究CYGB对LO-2脂质沉积的影响,通过油红O染色检测脂质沉积情况,GPO-PAP法检测细胞内甘油三酯水平,COD-PAP法检测细胞内胆固醇水平,通过RT-qPCR检测脂质生成相关基因ACACA、ACACB、FASN、ACSS1、ACSS2、ACSS3的mRNA表达水平,蛋白质免疫印迹法检测细胞炎性因子IL-1β,IL-6,TNF-α的表达水平,以及核转录因子-κB(NF-κB p65),磷酸化P65(NF-κB PP65)表达水平,用含浓度60,90μmol/L NF-κB抑制剂PDTC与高脂成分的培养基处理LO-2细胞48 h后检测细胞内甘油三酯和胆固醇水平.结果:LO-2经过高脂处理48 h后,两组细胞甘油三酯及胆固醇水平均上升,而实验组低于对照组(P0.05),90μmol/L NF-κB抑制剂PDTC处理后,甘油三酯和总胆固醇水平与未加入PDTC相比表现下调(P0.05);炎症相关因子IL-1β,IL-6和TNF-α在实验组中表达均低于对照组(P0.05);与对照组相比,实验组经高脂处理24 h后NF-κB信号通路受到抑制(P0.05).结论:CYGB下调LO-2细胞甘油三酯和总胆固醇水平,抑制炎性因子表达,抑制NF-κB信号通路,缓解LO-2脂质沉积.  相似文献   

9.
胆管细胞癌是原发性肝癌的一种,是目前肝癌诊疗的最大难点。检测槲皮素(Quercetin)对抗肿瘤药物作用于人肝内胆管细胞癌细胞系HCCC-9810的影响,确定其在胆管癌细胞治疗中的潜在作用。使用系列浓度梯度的槲皮素作用于HCCC-9810细胞,使用MTT法计算抑制率,确定槲皮素作用于HCCC-9810细胞的量-效关系。检测系列浓度梯度的抗肿瘤药物索拉菲尼(Sorafenib)、奥沙利铂(Oxaliplatin)和多西他赛(Docetaxel)对HCCC-9810细胞的杀伤作用,确定抗肿瘤药物作用的量-效关系。选取适宜的作用浓度,利用MTT法检测槲皮素对上述抗肿瘤药物杀伤HCCC-9810细胞的影响。利用蛋白印迹实验,检测槲皮素对上皮细胞标识物E-Cadherin以及间质细胞标识物N-Cadherin、Vimentin表达的影响。结果是槲皮素、索拉菲尼、奥沙利铂和多西他赛等能够剂量依赖地抑制HCCC-9810细胞的存活;选取2μmol/L为后续实验中的槲皮素作用浓度,该浓度的槲皮素预处理HCCC-9810细胞能够显著上调其对抗肿瘤药物的敏感性。索拉菲尼、奥沙利铂和多西他赛作用于HCCC-9810细胞的半数作用浓度(IC_(50))依次从(2.75±0.22)μmol/L、(0.83±0.12)μmol/L和(0.05±0.01)μmol/L下调为(0.31±0.5)μmol/L、(0.15±0.02)μmol/L和(0.01±0.00)μmol/L。作用机制实验结果表明,槲皮素处理能够下调HCCC-9810细胞中的间质细胞标识物N-Cadherin和Vimentin的表达,上调上皮细胞标识物E-Cadherin的表达。槲皮素能够通过抑制胆管癌细胞系EMT上调抗肿瘤的效能,在肝脏胆管细胞癌诊疗中具有潜在应用价值。  相似文献   

10.
为了探讨淫羊藿甙对高浓度葡萄糖抑制MC3T3-E1细胞成骨分化是否具有保护左右,采用含10 mmol/Lβ-磷酸甘油、50 mg/L维生素C以及10~(-8)mol/L地塞米松的α-MEM培养基诱导MC3T3-E1细胞成骨分化。根据培养基葡糖糖含量不同分别设置对照组(5. 5 mol/L葡萄糖)、高糖组(22 mol/L葡萄糖)和药物干预组(22 mol/L葡萄糖)。药物干预组各组细胞换液时分别加入0. 1μmol/L、1. 0μmol/L和10μmol/L的淫羊藿甙。通过茜素红染色、钙含量检测方法检测诱导培养25 d后细胞外钙含量,使用Real time PCR检测诱导培养7 d后成骨标志分子表达,观察各组MC3T3-E1细胞的成骨分化情况。使用活性氧检测试剂盒检测诱导培养7 d后的各组MC3T3-E1细胞内自由氧(reactive oxygen species,ROS)生成水平。结果表明:22mmol/L葡萄糖组细胞钙含量最低,成骨标志分子ALP、Osteorix及Runx2表达降低,细胞内自由氧生成水平升高,MC3T3-E1细胞成骨分化受到抑制。使用不同浓度淫羊藿甙干预后,细胞钙含量升高,成骨标志分子ALP、Osteorix及Runx2表达升高,细胞内自由氧生成水平降低,MC3T3-E1细胞成骨分化抑制作用呈现浓度依赖性的减弱。可见淫羊藿甙能够通过降低细胞内自由氧水平,减弱高浓度葡萄糖对成骨细胞分化的抑制作用。  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.
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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