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991.
992.
目的 探讨单纯疱疹病毒胸苷激酶基因(HSV-TK)/丙氧鸟苷(GCV)自杀基因系统对放射治疗的增敏作用。方法 口腔鳞癌细胞(Tca8113细胞系)经HSV-TK/GCV系统治疗后给予放射治疗,采用LQ和单击多靶(SHMT)模型分析细胞存活曲线参数。结果 细胞存活曲线分析显示:单纯放射治疗组其α为0.1074,β为0.0158,D0为2.2576,Dq为3.5413;与单纯放射治疗组比较,HSV-TK/GCV治疗组α(0.2127)和α:β(9.496)值大,D0(1.4526)和Dq(2.2257)值小,其放射增敏率(SER)为1.55。结论 HSV-TK/GCV系统具有放射增敏作用,可提高放射治疗对口腔鳞癌的治疗疗效。 相似文献
993.
994.
目的 探讨各种肿瘤转移促进基因在不同恶性肿瘤组织中的表达规律。方法 采用流式细胞术对 117例恶性肿瘤患者肿瘤组织的CD4 4S、CD4 4V5、CD4 4V6、cerbB 2基因编码蛋白表达水平进行了检测。结果 恶性肿瘤患者瘤组织细胞的CD4 4V5 +、CD4 4V6 +和cerbB 2 +细胞表达率均显著高于正常对照 (P <0 .0 1或P <0 .0 5 )。在各种肿瘤之间 ,不同肿瘤转移促进基因编码蛋白的表达水平有显著区别 (P <0 .0 1或P <0 .0 5 )。结论 各种肿瘤转移促进基因编码蛋白在不同恶性肿瘤组织中的表达水平明显不同 ,这提示不同肿瘤的转移机制可能不同。 相似文献
995.
宫颈肿瘤大小在Ⅰb ~Ⅱ期宫颈癌中的临床意义 总被引:2,自引:0,他引:2
[目的]探讨宫颈肿瘤大小的临床意义。[方法]自1992年1月至1997年12月收治手术治疗的Ⅰb~Ⅱ期(FIGO分期)宫颈癌患者398例,将其中302例有完整资料的患者根据宫颈肿瘤的最大横径分为<4cm组和≥4cm两组,分析了两组患者的生理病理因素、失败模式及其预后,并采用COX模型进行多因素生存分析。[结果]与<4cm组比较,≥4cm组中分期较晚,淋巴结转移,高位淋巴结转移及宫颈深肌层浸润的比例更高。宫颈大肿瘤组(≥4cm组)的单纯盆腔复发率(22.0%)高于<4cm组(7.6%)。宫颈大肿瘤组(≥4cm组)的5年生存率(59.29%)明显低于<4cm组(82.15%,P<0.01)。多因素生存分析显示宫颈局部肿瘤大小,淋巴结转移,阴道残端,肌层浸润深度及组织学类型是影响预后最重要的因素(P<0.05)。[结论]宫颈肿瘤≥4cm的患者更易发生深肌层浸润和盆腔淋巴结转移,盆腔复发率高,预后差。 相似文献
996.
Masahito Katoh Rick Wilmotte Marie-Claude Belkouch Nicolas de Tribolet Gianpaolo Pizzolato Pierre-Yves Dietrich 《Journal of neuro-oncology》2003,64(1):71-76
Survivin, a member of the inhibitor of apoptosis proteins gene family, was recently shown to be expressed by tumors originating from different cell lineages. There are also cumulative evidences that spontaneous immune response against survivin derived epitopes may occur. Here, using RT-PCR, Western-blot analysis and immunohistochemistry, we show that survivin is widely expressed by gliomas, meningiomas and schwannomas, both in vitro and in vivo. These data indicate that survivin may serve as an attractive target for immunotherapies designed for brain tumors. 相似文献
997.
Robert M. Prins Martin R. Graf Randall E. Merchant Keith L. Black Christopher J. Wheeler 《Journal of neuro-oncology》2003,64(1):45-54
One of the hallmarks of patients with glioblastoma multiforme (GBM) is profound lymphopenia mostly confined to the T cell lineage. A deficiency in the production of naïve T cells from the thymus could contribute to the lymphopenia seen in GBM patients. In this study we asked whether thymic function and the production of recent thymic emigrant (RTE) T cells from the thymus was influenced by intracranial (i.c.) glioma progression. We found significant thymic involution in animals with progressive i.c. gliomas. Involuted thymi from animals with progressive i.c. T9.F gliomas showed dramatic losses of CD4+CD8+ (DP) thymocytes. Microscopic analysis complemented those findings by demonstrating a reversal of the typical cortico-medullary structure. Significant increases in apoptosis accompanied the rapid loss of viable thymocytes, which was prevented in part by adrenalectomy, suggesting a dominant role for endogenous glucocorticoids. This thymic involution was also associated with a significant decrease in peripheral RTE T cells, reflecting the diminished thymic function. Finally, we found that CD8+ RTE T cells were enriched in progressively growing T9 gliomas, which points to an immunological role for RTE's in anti-glioma immunity. Our findings may shed light on the significance of thymic function for anti-glioma immunity and the response to immunotherapeutic treatment paradigms. 相似文献
998.
P Muretto F Graziano M P Staccioli I Barbanti A Bartolucci G Paolini D Giordano E Testa A De Gaetano 《Annals of oncology》2003,14(1):105-109
BACKGROUND: In gastric juice, high levels of the carcinoembryonic antigen (CEA) and the carbohydrate antigen 19-9 (CA 19-9) have been found to correlate with precancerous lesions and gastric cancer. So far, sampling of gastric juice has required upper endoscopy. In place of this invasive procedure, we investigated a new tool for the quantitation of tumor markers in gastric juice. MATERIALS AND METHODS: The study population consisted of healthy controls and consecutive subjects with suspected gastric cancer or dyspepsia/epigastric distress. Patients were asked to swallow a small gelatine capsule (14 mm in length and 5 mm in diameter) containing a pierced plastic cover and surrounding a piece of absorbent paper. The capsule was left in the gastric cavity for 60 min to allow saturation of the absorbent paper with gastric juice. A 45-50 cm length of nylon thread connected to the inner capsule was used to remove the device from the gastric cavity. After processing the absorbent paper for radioimmunoassay, CEA and CA 19-9 levels were correlated to the findings of upper endoscopy and biopsies of gastric mucosa or suspected lesions. RESULTS: The endogastric capsule did not cause any side-effects and 62 participants were fully compliant to the procedure. Assessable gastric juice samples were taken from 23 patients with gastric cancer, 15 patients with intestinal metaplasia or dysplasia, 12 patients with gastritis and 12 controls without gastric diseases. In the 12 samples of gastric juice from control patients, mean values of CEA and CA 19-9 were 1.1 +/- 0.9 ng/ml and 16 +/- 7.5 ng/ml, respectively. The mean levels of both markers were found to increase according to the severity of gastric lesions and in patients with cancer, mean CEA and CA 19-9 levels were 513 +/- 627 ng/ml and 545 +/- 510 ng/ml, respectively. Patients with precancerous lesions and cancer showed higher levels of CEA and CA 19-9 than patients with normal findings or gastritis (P <0.001). CONCLUSIONS: The endogastric capsule is a simple, non-invasive tool for the measurement of CEA and CA 19-9 levels in gastric juice. These values may discriminate between normal or minor pathologic changes and precancerous lesions or carcinomas. Further investigations are warranted, since this may represent a new method for gastric cancer screening. 相似文献
1000.
目的 探讨99mTc 氮 二 (N 乙基 N 乙氧基二硫代氨基甲酸盐 ) [99mTcN (NOEt) 2 ]应用于肿瘤诊断的可能性并与99mTc 甲氧基异丁基异腈(99mTc MIBI)肿瘤模型显像进行比较。方法 制备99mTcN (NOEt) 2 ,用上行薄层色谱法测定放化纯。各取 4只移植性艾氏腹水癌小鼠分别尾静脉注射99mTc MIBI或99mTcN(NOEt) 2 ,30min、2h、4h后进行全身后位静态显像。利用感兴趣区技术 ,分别计算不同时相肿瘤与头部 (T/H)、胸部 (T/C)、及健侧肢体对称部位 (T/L)的放射性比值。 4h后处死99mTcN (NOEt) 2 显像组小鼠 4只 ,取血并剥离脏器组织及肿瘤组织 ,称重 ,测量放射性计数 ,计算肿瘤与各脏器放射性比值。结果 99mTcN (NOEt) 2 室温下 4h保持稳定。99mTcN (NOEt) 2 选择性地有效的聚集于肿瘤组织。除腹部外其它组织靶 /非靶比值较高 ,注射2h后T/L比值达最高 ,为 4.87。99mTcN (NOEt) 2 显像组与99mTc MIBI显像组比较T/L比值差异有显著性 (P <0 .0 1)。体外测量肿瘤与血、肌肉、肺等脏器的单位重量放射性比值较高 ,与肝、小肠等腹部脏器的单位重量放射性比值较低。结论 在移植性艾氏腹水癌小鼠模型中99mTcN (NOEt) 2 从血液中清除很快 ,肿瘤摄取率高 ,有一定的滞留量 ,靶与非靶比值高 ,图像质量明显优于99mTc MIBI肿瘤 相似文献