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1.
淋巴样前体细胞由CD4-CD8-双阴性细胞发育为CD4 CD8 双阳性细胞,经历阳性选择和阴性选择进一步分化发育为具有免疫功能的成熟T细胞,即CD4 Th和CD8 Tc。T细胞发育的这一过程需要准确的调控机制,Hedgehog,BMP和Wnt信号通路参与了T细胞发育过程的调控。Hedgehog信号和BMP信号抑制T细胞的增殖和分化,Wnt信号对T细胞的发育起正调控作用。  相似文献   

2.
为了证明Oct4和SCF/c-kit、IL-6/IL-6st信号传导途径为干细胞增殖分裂重要调控因子,与肿瘤细胞的无限增殖有关。本研究通过沉默Oct4基因的方法拟探讨肿瘤细胞中Oct4基因和SCF/c-kit、IL-6/IL-6st信号传导以及细胞凋亡之间的关系,用Oct4 miRNA质粒载体沉默人宫颈癌HeLa细胞中的Oct4基因,用RT-PCR及免疫荧光标记法检测沉默Oct4基因对人宫颈癌HeLa细胞SCF/c-kit、IL-6/IL-6st和Bcl-2/Bax基因表达的影响。研究结果表明:人宫颈癌HeLa细胞高表达Oct4、SCF、c-kit、IL-6st基因和细胞凋亡相关基因Bcl-2、Bax。沉默Oct4基因使人宫颈癌HeLa细胞Oct4、SCF、c-kit、IL-6st和Bcl-2、Bax基因表达明显受到抑制,并促进了细胞凋亡,但对IL-6基因表达影响不大。证实了肿瘤细胞的无限增殖和Oct4对SCF/c-kit、IL-6/IL-6st信号传导以及Bcl-2基因表达调控有关。而且,肿瘤细胞在Oct4调控下高表达IL-6st以增加对IL-6的敏感性,导致肿瘤细胞在高水平IL-6环境中进一步恶化。  相似文献   

3.
目的:研究IL-4mRNA和IL-4蛋白在哮喘大鼠CD34+细胞中的转录表达及孟鲁司特(montelukast,MK)对其表达的影响.方法:将SD大鼠随机分为3组:哮喘组、MK组和正常对照组.用卵白蛋白制备大鼠哮喘模型.应用双抗体夹心酶联免疫吸附试验测定血浆中IL一4和γ-干扰素(IFN-γ)浓度;用MinjMACS磁珠分选系统分离骨髓CD34+细胞;采用sYBR GREEN I荧光实时定量PcR法测定CD34+细胞中IL-4 mJRNA的相对表达量.采用免疫组化技术测定CD34+细胞中IL-4蛋白的表达量.结果:哮喘组骨髓CD34+细胞中IL-4mR NA和IL-4蛋白的表达量高于其它各组(P<0.01);哮喘组除了IFN-γ水平低外,IL-4浓度和嗜酸性粒细胞(Eos)绝对值都是三组中最高的(P<0.01);除哮喘组外,其余组的各项指标相近(P>0.05).IL-4 mRNA表达量与IL-4浓度、Eos绝对值呈正相关(P<0.01),与IFN-γ浓度呈负相关(P<0.01).结论:哮喘大鼠骨髓CD34+细胞中IL-4mRNA的表达增强;孟鲁司特可以下调IL-4mRNA的表达.可能成为其抑制哮喘气道炎症形成的重要机制之一.  相似文献   

4.
目的阐明半相合供者淋巴细胞输注(DLI)抗中、高危非霍奇金氏淋巴瘤(NHL)的机制。方法通过预实验确定输注最佳时间及最佳浓度,并检测此条件下加入去CD8^+T细胞和去CD4^+T细胞半相合DLs培养后细胞的凋亡率及培养液中白细胞介素-2(IL-2)的浓度。培果在最佳输注时间(培养后24小时)、最佳浓度(2.5×10^5/ml)下加入去CD8^+T细胞半相合DLs进行培养,淋巴瘤细胞凋亡率(17.6±2.5)%与对照组(4.6±1.2)%及加入去CD4^+T细胞半相合DLs(5.2±1.6)%相比较,有显著性差异,而且加入去CD4^+T细胞半相合DLs的培养液中IL-2浓度显著高于加入去CD4^+T细胞者和对照组。结论CD4^+T细胞在移植物抗淋巴瘤效应中可能起着比CD8^+T细胞更重要的作用,在临床使用中,选择性去除CD4^+T细胞,可减少或减轻移植物抗宿主病(CVHD),并且不影响移植物抗淋巴瘤效应。IL-2在半相合DIs发挥移植物抗淋巴瘤效应过程中可能起着重要的作用。  相似文献   

5.
应用免疫组织化学PAP法,对26例常见恶性肿瘤冰冻组织切片中肿瘤浸润淋巴细胞(TIL)进行了原位分析,以了解TIL的组成及分布等原位特征。结果显示:(1)TIL中主要为CD_3~ 细胞,其中CD_4~ 相似文献   

6.
目的:本研究探究获得性免疫缺陷综合征(AIDS)和人类免疫缺陷病毒(HIV)阳性个体患者外周血炎症因子和肠道菌群的变化,同时探讨了肠道菌群、外周血炎症因子和CD4~+T淋巴细胞之间的关系。创新点:首次探讨了AIDS和HIV阳性个体患者中肠道菌群、外周血炎症因子和CD4~+T淋巴细胞之间的关系。方法:从艾滋病组和对照组分别收集30份血液和粪便样本。使用酶联免疫吸附测定(ELISA)法测定肿瘤坏死因子(TNF-α)和白细胞介素-6(IL-6)的水平;用流式细胞仪测定CD4~+T淋巴细胞数目;采用实时定量聚合酶链式反应(q RT-PCR)法检测双歧杆菌、乳酸菌、大肠杆菌、粪肠球菌和屎肠球菌的m RNA水平;采用Spearman分析肠道菌群、炎症因子与CD4~+T淋巴细胞之间的相关性。结论:不但AIDS/HIV患者体内肠道菌群紊乱,而且肠道菌群数量与CD4~+T淋巴细胞数量以及TNF-α、IL-6水平存在相关性。  相似文献   

7.
重症肌无力是由乙酰胆碱受体抗体(AChRAb)引起的自身免疫性疾病。根据分泌细胞因子的不同,将辅助性T细胞分为Th1和Th2细胞两个亚类,Th1分泌IFN-γ,IL-2为主,参与细胞免疫;Th2分泌IL-4、IL-5、IL-6、IL-10等,参与体液免疫。研究表明细胞因子在重症肌无力发病机制中起重要作用。  相似文献   

8.
应用免疫组织化学PAP法及多种单克隆抗体,对12例常见消化系统恶性肿瘤进行了原位研究。结果显示:①TIL在肿瘤局部主要分布于癌间质区,而癌实质区仅有极少数TIL浸润;②TIL中的主导细胞为CD_3~ T细胞,且无论在实质区还是在间质区CD_4~ 细胞均少于CD_8~ ,癌间质区CD_4~ /CD_8~ 比值大于癌实质区;③无论在癌实质区还是在癌间质区,均有部分CD_(25)~ 或HLA-DR~ TIL存在,对于这些变化的内在机制文中也作了探讨。  相似文献   

9.
目的:探讨流式微球阵列术(Cytometric Bead Array,CBA)检测Th1/Th2细胞因子在V型狼疮性肾炎(LN)患者血清中的表达及意义。方法:用CBA法检测20例V型LN患者和20例正常人血清中Th1(TNFα、IFNγ)和Th2(IL-4和IL-5)类细胞因子表达情况。结果:V型LN组Th1类细胞因子TNFα和IFNγ表达均高于正常对照组,而正常对照组中IL-4和IL-5则高于狼疮肾患者,两组中IL-2表达无差异。结论:Th1和Th2类细胞因子平衡/紊乱在狼疮肾患者肾组织损害中可能起一定作用。CBA法检测Th1/Th2细胞因子是一种高效、简便和敏感度高的方法。  相似文献   

10.
目的探讨Rock抑制剂Fasudil对实验性自身免疫性脑脊髓炎(EAE)发病起始环节的外周免疫调节机制。方法将雌性C57BL/6小鼠分为CFA组、EAE组和Fasudil组。Fasudil组动物免疫后第7 d腹腔给予Fasudi(l50mg/kg.d),连续给药14 d。免疫后隔天观察各组小鼠临床评分和体质量变化。在免疫后28 d处死动物,取脊髓进行HE染色和髓鞘染色,制备脾脏单个核淋巴细胞(MNC),测定细胞增殖和细胞因子IL-4,IL-10,IL-1β,IFN-γ的含量,流式细胞术观察CD4,CD25调节性T细胞的比例,部分脾脏组织和MNC涂片行免疫组化荧光染色观察Rock的表达。结果Fasudil在EAE外周免疫组织和细胞通过下调Rock的表达,抑制Rock的激活,明显改善EAE的临床症状评分(P〈0.05);减轻EAE外周炎性细胞向中枢的浸润,缓解神经髓鞘的脱失;经Fasudil干预可以下调EAE外周特异性MOG35-55反应性T淋巴细胞增殖能力,下调炎性细胞因子IFN-γ和IL-1β水平,升高保护性细胞因子IL-10水平,促进CD4,CD25调节性T细胞比例增加。结论 Rho/Rock信号通路的激活在EAE的发病中起着重要作用,应用Rock抑制剂--Fasudil抑制EAE免疫病理过程中外周免疫细胞激活这一起始重要环节,减少炎性细胞的中枢浸润,缓解EAE的临床症状。  相似文献   

11.
《海外英语》2007,(5):44-45
It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,  相似文献   

12.
《海外英语》2007,(4):36
There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love.  相似文献   

13.
王菲 《华章》2007,(12):273-273
Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject.  相似文献   

14.
裴水妹 《华章》2007,(11):196
Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities.  相似文献   

15.
16.
1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec…  相似文献   

17.
Today, Sunday morning, I sit thinking and typing at my computer. My thoughts are in my homeland, India and my body is in China. The body is here and mind there for a good reason. Mr. Hu is president and I am resident and both are in each other's countries (what a difference the absence of one small letter makes!). Mr. Hu will return in a few days and I will stay on longer.  相似文献   

18.
STORIES     
正A One day a pig went to the stable(马棚)to see his good friend,an oldhorse,and was going to stay there forthenight.Night came and it was time forsleep.The pig went into the straw heap(稻草堆)and lay comfortably.A longtime passed,but the horse was stillstanding there and did not move.Thepig asked the horse why he did not go tosleep."Standing like this is the begin-ning ofsleeping,"answered the horse.  相似文献   

19.
正1.Any fool can count the seeds in an apple.Only God can count all the apples in one seed.2.Happy families are all alike;every unhappy family is unhappy in its own way.3.Memories are the key not to the past,but to the future.4.Sometimes in the dark you see what you want to see.5.There is a great difference between  相似文献   

20.
正Scope and Policy The Journal of Chongqing University-English Edition(JCQU-E)is a peerreviewed journal publishing research articles in multiple disciplines of science and technology,covering civil and environmental engineering,chemical engineering,biotechnology,mechanical and electrical engineering,computer and data processing,mining,metallurgy,materials science,and interdisciplines thereof.  相似文献   

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