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11.
Objective To construct a eukaryotic expression system with pcDNA3-PfCSP/Hela for the Circ umsporozoite protein (CSP) gene of Plasmodium falciparum (P.falciparum), t o observe the immune responses in BALB/c mice induced by the expressed proteins .Methods The recombinant plasmid pcDNA3-PfCSP was transformed into the Hela cell line. The expressed protein was isolated and analyzed by using SDS-PAGE and used for immunization of BALB/c mice by subcutaneous, intravenous, and intraperitone al adminstration.Enzyme-linked immunosorbent assay(ELISA), Dot-ELISA, Wester n blot, T lymphocyte proliferation test, natural killer cell(NKC) activity assay , and CD4(+) and CD8(+) T cell detection were used for observation of humoral an d cellular immune responses.Results Immune sera strongly reacted with the expressed protein, antibody titer was up to 1∶6400 as detected by ELISA.Western blot analysis revealed a specific b and at 38.3 Kda.When the spleen cells of normal and immunized BALB/c mice we re specifically stimulated with expressed protein, the optical densities were 0 .12±0.03 and 0.34±0.04, respectively.The latter were significantly highe r than the former (P<0.01).We used the MTT colorimetric assay to measure NKC activity of mice spleen.The results showed that the NKC activity of immuni zed BALB/c mice was remarkably higher than that of the controls (P<0.05). CD4(+) and CD8(+) T cells were detected by using monoclonal antibody immunofluor escence methods.The results showed that the percentage of CD4(+) and CD8(+) T cells of immunized group were significantly higher than that of control group ( P<0.05).Conclusions The humoral and cell-mediated immune responses and elevated NKC activity to pr oducts made with a eukaryotic expression system could be specifically detected i n BALB/c mice.These findings indicate that the expressed protein could enhance the immune function in mice. 相似文献
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0 引言 我科 1996 / 1998分别应用消痔灵与强的松龙混合液、消痔灵液、强的松龙液行鼻息肉内 ,鼻息肉蒂部注射治疗鼻息肉各 5 0例 ,并设对照组为鼻腔滴入及口服类固醇激素 5 0例 ,合计 2 0 0例 ,观察并对比其疗效 .1 对象和方法1.1 对象 男 12 8例 ,女 72例 ,年龄 8~ 78(平均 38)岁 ,病程 32 a~ 45 (平均 4.5 ) a.其中在本次治疗前做过一次鼻息肉摘除术后复发的 2 7例 ,做过 2次或 2次以上手术的 12例 .主要症状为鼻塞、流脓涕、头痛及嗅觉减退 .全部病例治疗前均行鼻窦 X线拍片 ,其中上颌窦炎 12 5例、筛窦炎 5 8例、蝶窦炎 2例、… 相似文献
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阿克拉霉素A聚氰基丙烯酸异丁酯毫微粒冻干针剂体内外抗肝癌活性 总被引:6,自引:0,他引:6
阿克拉霉素A聚氰基丙烯酸异丁酯毫微粒的冻干针剂,能明显抑制体外培养人肝癌细胞株7703的生长,IC50为0.28μg·ml-1。在0.8μg·ml-1浓度时,克隆形成抑制率为90%,抑制作用有明显剂量依赖关系而未见明显时间依赖关系。静脉给药后,对常位移植人肝癌模型裸小鼠的抑瘤率为86.84%,肿瘤细胞增殖活性阳性率为20.83%。体内外均显示明显的抗肝癌活性,且体内抗肝癌活性比阿克拉霉素A冻干针剂强。 相似文献
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Aim: Findings of hypoxia prior to death and involvement of a dysregulation of the serotonergic network in sudden infant death syndrome (SIDS) may indicate that brain‐derived neutrophic factor (BDNF) also is of importance with regard to sudden unexpected infant death. Based on this, the purpose of this study was to investigate the BDNF val66met polymorphism in SIDS cases, cases of infectious death and controls. Methods: The polymorphism was investigated in 163 SIDS cases, 34 cases of infectious death and 121 controls, using real‐time PCR and fluorescence melting curve analysis. Results: There were no differences in val66met genotype distribution between neither the SIDS cases nor the cases of infectious death and controls (p = 0.95 and p = 0.52, respectively). Conclusion: The study indicates that the val66met polymorphism is not important for sudden unexpected infant death. However, several other SNPs in the BDNF gene, as well as in other genes involved in this pathway, including G‐protein, have to be investigated to fully exclude any involvement of BDNF in SIDS. 相似文献
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Terminal differentiation surface antigens of myelomonocytic cells are expressed in human promyelocytic leukemia cells (HL60) treated with chemical inducers 总被引:12,自引:0,他引:12
The expression of two surface antigens present on the cell membrane of both human granulocytes and monocytes was studied during the process of myelomonocytic differentiation using two monoclonal antibodies (B9.8.1 and B13.4.1). These surface antigens are not present on immature myeloid cells nor on nonmyeloid hematopoietic cells, but can be detected when the cells are terminally differentiated. Among the bone marrow cells, B13.4.1 binds to metamyelocytes and B9.8.1 to metamyelocytes and a fraction (30%) of myelocytes. HL60 human promyelocytic leukemia cells did not react with such monoclonal antibodies. However, when such cells were induced to differentiate in vitro into mature myeloid elements by treatment with retinoic acid or dimethyl sulfoxide, 70%--90% of the differentiated cells expressed both surface antigens. Cell sorting studies on these treated HL60 cells indicated that myelocytes and metamyelocytes were the most immature cells expressing such markers. Expression of the two surface antigens was also observed when HL60 cells were induced to differentiate into monocyte/macrophage cells by treatment with the tumor promoter 12-O- tetradecanoyl-phorbol-13-acetate. Thus, human promyelocytic leukemia cells induced to differentiate in vitro by treatment with specific chemical agents express membrane antigens in the same pattern as normal bone marrow myeloid cells at the corresponding stage of differentiation. 相似文献