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树突状细胞负载肝癌抗原肽疫苗体外诱导特异性免疫学反应的研究 总被引:1,自引:1,他引:1
目的:研究树突状细胞(dendritic cell,DC)负载肝癌抗原肽EPVTKAEML体外诱导特异性CTL的能力及其抑癌效果。方法:用顺序特异引物聚合酶链反应技术(PCR—SSP)选择HLA—B7表型供者,从脾组织中分离、培养DC-EPVTKAEML特异性CTL。用^51Cr释放法检测CTL的杀伤活性,并用抗HLA-1分子单抗(mAb)进行杀伤抑制实验。结果:找到4例HLA-B7杂合子供者,用DC负载HLA-B7限制的抗原肽EPVTKAEML可诱导特异性CTL反应,对肝癌细胞HHCC有较强的杀伤作用。结论:DC负载抗原肽EPVTKAEML在体外可诱发较强的特异性免疫反应。 相似文献
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作者采用PharmaciaSephacrylS—300凝胶色谱柱,建立了IgG类McAb的一步法制各级纯化方法。该法是将McAb腹水直接上样,用pH7.410mmol/LPBS洗脱(流速0.5ml/min),即得到纯化的McAb。一次上样量40~50ml腹水,回收率为85%-90%.整个纯化周期4h。纯化的McAb经SDS—PAGE测定,纯度>90%,免疫组化ABC法测定活性为1:80000(7.8×10-11mol/L)。该法操作简单、快速,只要有一台核酸/蛋白检测仪,便可进行制备级水平的纯化。 相似文献
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目的:构建受AFP顺式作用元件调控的超抗原表达载体,将SEA(D227A)特异性的表达于AFP阳性肝癌细胞膜表面。方法:PCR扩增AFP基因启动子、增强子、linker—CD80tm和SEA(D227A)。将上述片断插入逆转录病毒载体pLXSN的多克隆位点,构建AFP基因顺式作用元件调控的肝癌特异性减毒超抗原表达载体(pLXSN SEA(D227A)—linker—CD80tm)。通过脂质体介导,以表达载体转染表达或不表达AFP的肿瘤细胞系,用RT—PCR和间接免疫荧光染色,检测SEA的表达。结果:成功地将AFP基因的启动子、增强子、linker—CD80tm和SEA(D227A)克隆到逆转录病毒载体pLXSN的多克隆位点,酶切鉴定和DNA序列分析无误,RT—PCR和间接免疫荧光法检测证实,SEA(D227A)能在AFP阳性的肝癌细胞膜特异性表达。结论:AFP顺式作用元件修饰的超抗原表达载体的构建,为下一步用其强化肝癌的免疫治疗奠定了基础。 相似文献
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原发性开角型青光眼与高血压的关系 总被引:4,自引:0,他引:4
目的 探讨原发性开角型青光眼与高血压病的关系.方法 随机选择确诊原发性开角型青光眼50例,高血压病50例,观察眼压、血压、视乳头C/D比,视野,归纳总结.结果 50例原发性开角型青光眼中,血压高者25例(50%).50例高血压病中,眼压高者38例(76%),视野损害40例(80%),光敏度下降35例(70%),中心暗点25例(50%),周边视野缩小17例(34%),生理盲点扩大17例(34%).结论 原发性开角型青光眼与高血压病有极大关联. 相似文献
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施万细胞对大鼠脊髓半横切后背核神经元存活及其表达NOS的影响 总被引:5,自引:2,他引:5
目的:探讨移植的施万细胞对大鼠脊髓半横切后背核神经元存活及其表达NOS的影响。方法:50只成年SD大鼠被分为实验组和对照组。在胸11脊髓段半横切后立即在损伤处移植入施万细胞。结果:脊髓半横切后,15d和25d对照组L1脊髓段损伤侧背核神经元的存活数均比未损伤侧的明显减少。存活的神经元胞体出现明显皱缩,有些神经元呈现NADPH-d阳性。15d和25d施万细胞组L1脊髓段损伤侧背核神经元的存活数则比同期对照组的明显增加,表达NOS的存活神经元数也随之增多。但存活的神经元胞体仍然是皱缩的。结论:移植的SCs可促进受损伤的背核神经元存活及其表达NOS,但不能阻止其胞体出现皱缩。 相似文献
28.
Carcinoma of the cervix is typically treated with a combination of intracavitary brachytherapy and external beam radiation. The external beam dose is delivered with whole pelvis fields followed by split fields that protect midline organs at risk (bladder and rectum) while treating the parametria. Three approaches have been developed to shield midline structures: a simple rectangular block, a block customized to a single brachytherapy isodose line, and a step wedge filter constructed to conform to multiple brachytherapy isodose lines. A customized step wedge filter has the potential to produce a more homogeneous dose distribution but has not achieved widespread use due to labor intensive construction. We have developed a simple, novel method to produce a custom midline step wedge using dynamic multileaf collimation (dMLC). A comparison of film measurements in a phantom with the dose calculated by a commercial treatment planning system demonstrated agreement within 3% or 3 mm. The technique requires delivery times comparable to conventional techniques. 相似文献
29.
Shen S Duan J Fiveash JB Brezovich IA Plant BA Spencer SA Popple RA Pareek PN Bonner JA 《Medical physics》2003,30(12):3196-3205
The capability of a commercial respiratory gating system based on video tracking of reflective markers to reduce motion-induced CT planning and treatment errors was evaluated. Spherical plastic shells (2.8-82 cm3), simulating the gross target volume (GTV), were placed in a water-filled body phantom that was moved sinusoidally along the longitudinal axis of the CT scanner and the accelerator for +/- 1 cm at 15-30 cycle/min. During gated CT imaging, the x-ray exposure was initiated by the gating system shortly before the end of expiration (so that the imaging time would be centered at the end of expiration); it was terminated by the scanner after completion of each slice. In nongated CT images, the target appeared distorted and often broken up. GTVs volume errors ranged 16%-110% in axial scans, and 7%-36% in spiral scans. In gated CT images, the spheres appeared 3 and 5 mm longer than their actual diameters (volume errors 2%-16%), at the respective respiration rates of 15 and 20 cycles/min. At 30 cycles/min the target appeared 1 cm longer, and volume error ranged 25%-53%. During treatment, gating kept the beam on for a duration equal to the CT acquisition time of 1 s/slice. The difference in positional errors between gated CT and portal films was 1 mm, regardless the size of residual motion errors. Because of the potential of suboptimal placement of the gating window between CT imaging and treatment, an extra 1.5-2.5 mm safety margin can be added regardless of the size of residual motion error. For respiratory rates > or = 30 cycles/min, the effectiveness of gating is limited by large residual motion in the 1 s CT acquisition time. 相似文献
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AIMS: It has been postulated that the recent world-wide increase in the incidence of non-Hodgkin's lymphoma (NHL) may have been caused by human infection with simian virus 40 (SV40) (a lymphotropic monkey virus that was introduced to man from contaminated poliovirus vaccines between 1955 and 1963); therefore, we set out to determine the incidence of SV40 DNA positivity in lymphoma samples from patients in Tasmania, Australia. METHODS: One hundred lymph node samples, 50 from patients with lymphomas and 50 from controls, were tested using PCR amplification of three SV40-specific primer pairs followed by dot-blot hybridisation. RESULTS: All of the samples tested contained amplifiable DNA, but none contained amplifiable SV40 sequences with any of the primer sets used. CONCLUSIONS: Our results demonstrate absence of SV40 in the lymphoid tissues of our study population in Tasmania, Australia. SV40 does not explain the increasing incidence of NHL in our population. 相似文献