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1.
To set up a method of amplification for the whole CagA gene of Helicobacter pylori and its fingerprinting by restriction fragment length polymorphism(RFLP),nested PCR was employed in combination with TD-PCR to amplify the gene and EcoRI and Hind Ⅲ were used to generate the RFLP fingerprinting.Target DNA fragments from 13 of 20 samples were successfully amplified and the relevant RFLP fingerprintings were obtained.It is concluded that the method can be used to amplify the whole CagA gene and CagA gene has apparent diversity of RFLP profile.  相似文献   
2.
肿瘤坏死因子-α(TNF-α)通过多种机制参与卵巢癌的生物学变化,TNF-α及其受体分泌量的变化可能与卵巢癌进展有关。近年来采用其治疗卵巢癌,主要集中在利用TNF-α与多种化疗药物产生协同的细胞毒作用以及促使内源性TNF-α的产生来杀伤癌细胞。TNF-α重组蛋白疗法、基因疗法和TNF-α单克隆抗体疗法为卵巢癌的治疗带来希望。  相似文献   
3.
目的了解IFN-α对HuH7细胞固有免疫分子APOBEC3G表达的影响及其机制。方法HuH7细胞给予不同浓度的IFN-α(0 U/ml、100U/ml、400U/ml、800U/ml and 1200U/ml)刺激,10h后提取细胞总RNA,RT-PCR和实时定量RT-PCR检测HuH7细胞内APOBEC3G的mRNA水平变化,Western blot分析APOBEC3G蛋白水平的表达;分别构建不同长度的含有IRF-E(IFN regulatory factor element)位点的APOBEC3G起始密码上游序列报告质粒、不含IRF-E和IRF-E位点突变的虫荧光素酶报告质粒,报告基因分析IFN-α刺激后APOBEC3G起始密码上游IPF-E位点对APOBEC3G表达的影响。结果IFN-α上调HuH7细胞APOBEC3G mRNA和蛋白水平的表达,并具有剂量依赖的效应。序列分析发现APOBEC3G起始密码上游的-298~-283和-57~-47位碱基分别存在IRF-E和ISRE(IFN stimulated re- sponse element)序列。报告基因分析结果显示,干扰素使含有IRF-E序列的APOBEC3G启动子报告质粒的虫荧光素酶的活性增加6~8倍,而不含IRF-E序列和IRF-E位点突变的报告质粒的虫荧光素酶活性在干扰素刺激后几乎没有变化。结论IFN-α可通过IRF-E位点上调APOBEC3G mRNA和蛋白水平的表达,从而发挥抗病毒效应。  相似文献   
4.
目的: 探讨八肽胆囊收缩素(CCK-8)对静息巨噬细胞B7.1和B7.2表达及其协同刺激功能的影响。方法:用CCK-8(10-12-10-6 mol/L)孵育小鼠腹腔巨噬细胞一定时间,采用流式细胞术分析细胞表面B7.1和B7.2含量的变化。用免疫磁珠从小鼠脾细胞分离CD4+T细胞,按4∶〖KG-*2〗1数量比与腹腔巨噬细胞(预先用CCK-8和/或抗B7.1抗体、抗B7.2抗体、CCK1R拮抗剂CR1409、CCK2R拮抗剂CR2945孵育24 h)共同体外培养,同时加入ConA 5 mg/L,采用[3H]掺入法测定CD4+T细胞增殖反映巨噬细胞的协同刺激活性。结果:CCK-8可上调静息巨噬细胞B7.1及B7.2的表达,并增强巨噬细胞的协同刺激活性。CCK-8的作用呈剂量依赖性,最大效应剂量是在10-9-10-7 mol/L之间。抗B7.2抗体可减轻CCK-8增强巨噬细胞协同刺激活性的作用,CR1409及CR2945均能逆转CCK-8的上述作用,且CR1409的作用较CR2945更明显。结论:CCK-8通过上调巨噬细胞B7.2表达而增强其协同刺激活性,该作用由CCK1R及CCK2R介导,其中CCK1R起主要介导作用。  相似文献   
5.
目的:探讨多种刺激剂对肿瘤引流淋巴结(TDLN)细胞分泌细胞因子的影响及其抗肿瘤效应和机制。方法:采用ELISA和Griess法测定不同刺激组(分别为IL2、IL2 自身肺癌细胞抗原、IL2 GMCSF IL4 自身肺癌细胞抗原和IL2 GMCSF IL4 LPS)刺激TDLN后第7、14、21天,分泌IL12p70、IFNγ、TNFα和NO的水平。结果:IL2 GMCSF IL4 自身肺癌细胞抗原和IL2 GMCSF IL4 LPS组刺激的TDLN细胞中,CD83 细胞的比率明显增多,分泌IL12p70、IFNγ及TNFα的水平也明显高于IL2和IL2 自身肺癌细胞抗原刺激组,IL2 GMCSF IL4 LPS组刺激的TDLN细胞分泌NO的水平明显高于其他3组。各种刺激剂刺激TDLN细胞后,分泌IL12p70、IFNγ和NO的水平在第14天时达到高峰。结论:不同刺激剂诱导TDLN细胞中的CD83 细胞数量不同,故具有不同的抗肿瘤活性。  相似文献   
6.
Objective To examine the in vivo anti-metastatic effect of enhanced expression of CD40L cDNA in murinc ovarian cancer OVUM cells (CD4OL-OVHM) injected into the spleen on liver metastasis in mice. Methods OVUM cells were inoculated into the spleen of 6 ~ 8 week-old female B6C3F1 (C57BL/6N × C3H/He) mice. The established liver metastasis was identified by histopathology (HE staining). OVUM cells, DNA-pMKITneo-OVHM cells or CD40L-OVHM cells were inoculated into the spleen of female B6C3F1 mice and the expressions of CD11c in splenic cells were detected by flow cytometry. The specific cytotoxicity of splenic cells was detected by MTT assay, and the serum cytokines of IFN-γ, TNF-α, IL-12, IL4 and IL-10 of the mice were measured by enzyme linked immunoabsorbent assay. The liver metastases and the survival time of the mice were also recorded. Results The mouse models with liver metastasis by injecting tumor cells into the spleen of mice were established. The expression of CD11c and the specific killing rote in CD40L-OVHM cells group was significantly higher than that in the OVHM cells group and DNA-pMKITneo-OVHM cells group. The expressions of IFN-γ, TNF-α and IL-12 in the CD40L-OVHM cells group were much more increased than OVHM cells group and DNA-pMKITneo-OVHM cells group, but the expressions of IL-4 and IL-10 in the CD40L-OVHM cells group were decreased significantly (P < 0.05). The average weights of livers and spleens of mice in CD40L-OVHM cells group were significantly lower than those of DNA-pMKITneo-OVHM cells group and OVHM cells group. The survival time of mice in CD40L-OVHM cells group was also significantly longer than that in the OVHM cells group and DNA-pMKITneo-OVHM cells group (P < 0.05). Conclusion The data directly demonstrate that the expression of CD40L in ovarian cancer cells (CD40L-OVHM) can enhance the proliferation and differentiation of dendritic cells in the spleen and induce specific cytotoxic effect of T cells in the spleen, and may regulate the immune function of peripheral blood cells and the immune balance between Thl cells and Th2 cells, which maybe the possible mechanism induced by CD40L in mice inhibiting the development of liver metastasis.  相似文献   
7.
The objective of this study was to characterize the genome structure of duck hepatitis B virus (DHBV) isolated from Hubei brown ducks. The natural carrier rate of DHBV in adult ducks from Hubei area was investigated and the DHBV DNA-positive serum screened out. The complete genome of a DHBV strain was amplified by polymerase chain reaction (PCR) and cloned into T vector and sequenced. The results showed that the carrier rate of DHBV in Hubei brown ducks was 10 %. This strain (GenBank accession number DQ276978) had a genome of 3024 nucleotides with three overlapping open reading frames encoding the surface, core and polymerase proteins respectively. Comparison of the strain with 17 DHBV strains registered in GenBank revealed a homology from 89.3 % to 93.5 % at the nucleotide level. The sequences of the structural and functional domains of these proteins were highly conserved. The strain was found to share more signature amino acids in the polymerase genes with the "Chinese" DHBV strains than those of the "Western" country strains. This finding was also corroborated by a phylogenetic tree analysis. Therefore, the DQ276978 might belong to a subtype of the Chinese DHBV strains.  相似文献   
8.
<正>2009年3月~2011年12月,我科应用MIPPO技术结合锁定加压钢板(LCP)治疗22例肱骨近端骨折患者,疗效满意,报道如下。1材料与方法1.1病例资料本组22例,男8例,女14例,年龄27~76岁。骨折按Neer分型:二部分8例,三部分11例,四部分3例。1.2手术方法臂丛麻醉或全身麻醉。患者半卧位,手臂自然下垂,C臂机前后  相似文献   
9.
目的 利用RNA干扰技术探讨人宫颈癌基因(HCCR)对肝癌细胞增殖、凋亡的影响及其可能的分子机制. 方法 构建表达HCCR小干扰RNA的真核表达质粒pRIV2-siHCCR,将其转染肝癌细胞株HepG2细胞,定量PCR、Westem blot检测HCCR及其相关基因的表达,四甲基偶氮唑盐法检测细胞增殖状态,流式细胞术观察细胞凋亡与细胞周期变化. 结果 成功构建真核表达质粒pRIV2-siHCCR,其表达的HCCR siRNA可有效抑制HepG2细胞内HCCR的表达,细胞增殖受到抑制,细胞凋亡增加.Western blot结果显示HCCR小干扰RNA作用HepG2细胞后,细胞内P53蛋白的表达降低,P15蛋白的表达明显升高,而PTEN、P16、P27蛋白水平没有明显改变. 结论 HepG2细胞中HCCR蛋白下调后,细胞增殖受到抑制,凋亡细胞增多,其作用机制可能与蛋白质P53、P15有关.  相似文献   
10.
Objective To examine the in vivo anti-metastatic effect of enhanced expression of CD40L cDNA in murinc ovarian cancer OVUM cells (CD4OL-OVHM) injected into the spleen on liver metastasis in mice. Methods OVUM cells were inoculated into the spleen of 6 ~ 8 week-old female B6C3F1 (C57BL/6N × C3H/He) mice. The established liver metastasis was identified by histopathology (HE staining). OVUM cells, DNA-pMKITneo-OVHM cells or CD40L-OVHM cells were inoculated into the spleen of female B6C3F1 mice and the expressions of CD11c in splenic cells were detected by flow cytometry. The specific cytotoxicity of splenic cells was detected by MTT assay, and the serum cytokines of IFN-γ, TNF-α, IL-12, IL4 and IL-10 of the mice were measured by enzyme linked immunoabsorbent assay. The liver metastases and the survival time of the mice were also recorded. Results The mouse models with liver metastasis by injecting tumor cells into the spleen of mice were established. The expression of CD11c and the specific killing rote in CD40L-OVHM cells group was significantly higher than that in the OVHM cells group and DNA-pMKITneo-OVHM cells group. The expressions of IFN-γ, TNF-α and IL-12 in the CD40L-OVHM cells group were much more increased than OVHM cells group and DNA-pMKITneo-OVHM cells group, but the expressions of IL-4 and IL-10 in the CD40L-OVHM cells group were decreased significantly (P < 0.05). The average weights of livers and spleens of mice in CD40L-OVHM cells group were significantly lower than those of DNA-pMKITneo-OVHM cells group and OVHM cells group. The survival time of mice in CD40L-OVHM cells group was also significantly longer than that in the OVHM cells group and DNA-pMKITneo-OVHM cells group (P < 0.05). Conclusion The data directly demonstrate that the expression of CD40L in ovarian cancer cells (CD40L-OVHM) can enhance the proliferation and differentiation of dendritic cells in the spleen and induce specific cytotoxic effect of T cells in the spleen, and may regulate the immune function of peripheral blood cells and the immune balance between Thl cells and Th2 cells, which maybe the possible mechanism induced by CD40L in mice inhibiting the development of liver metastasis.  相似文献   
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