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991.
GSTM1与肺癌易感性的病例对照研究 总被引:3,自引:0,他引:3
[目的]研究广东人群谷胱甘肽-S-转移酶1(GSTM1)基因多态性和饮酒与肺癌易感性的关系.[方法]采用病例对照研究(病例组91例,对照组138例),调查研究对象的饮酒习惯,应用PCR技术检测GSTM1的基因型.[结果]对照组GSTM1基因频度与肺癌组之间差异无统计学意义,有饮酒习惯者发生肺癌的危险性升高(OR=3.33,P<0.01).有饮酒习惯及其GSTM1缺陷型的个体,与无饮酒习惯及其GSTM1正常个体相比,明显增加了患肺癌的易感性(OR=5.89,P<0.01).[结论]饮酒与肺癌有关系,GSTM1缺陷型的饮酒者肺癌危险性增加. 相似文献
992.
目的 研究血管内皮细胞在受60 Coγ射线照射后粘附分子CD5 4的表达与单核样细胞在血管内皮细胞上粘附变化的关系 ,观测抗氧化剂PDTC预处理对CD5 4表达及白细胞粘附的影响。方法 培养的ECV30 4细胞接受 16Gy60 Coγ放射线照射后不同时点 ,检测视黄酸诱导的单核样HL 6 0细胞在内皮细胞上的粘附数量 ,内皮细胞CD5 4mRNA及蛋白表达 ,核转录因子κBDNA结合活性以及抗氧化剂PDTC预处理对上述指标的影响。结果 照射后 8h ,HL 6 0细胞粘附数较对照显著上升 ,2 4h时较对照增加 77%。受照后 2h ,CD5 4mRNA水平较对照增加 36 % ,2 4h增加 182 %。照射后 4~ 32h ,CD5 4蛋白表达较对照增加 6 6 %~ 2 6 8%。NF κB DNA结合活性在照射后 2h达峰值 ,较对照增高 97%。PDTC预作用后 2h ,NF κB DNA结合活性较未处理组下降了 4 4 % ,作用后 4h ,CD5 4mRNA表达量下降 35 % ,同时HL 6 0细胞粘附数减少 2 6 %。结论 CD5 4表达上调是60 Coγ射线照射引起单核细胞在内皮细胞上... 相似文献
993.
Kathleen M Egan Qiuyin Cai Xiao-Ou Shu Fan Jin Tian-Li Zhu Qi Dai Yu-Tang Gao Wei Zheng 《Cancer epidemiology, biomarkers & prevention》2004,13(2):197-204
PURPOSE: We studied the relation of breast cancer to common deletion mutations in GSTM1 and GSTT1 and the functional Ile(105)Val polymorphism in GSTP1 in a large, population-based case-control study conducted in China and performed a meta-analysis to summarize the literature. EXPERIMENTAL DESIGN: In the case-control study, a total of 1144 breast cancer cases and 1221 community controls were genotyped for GSTM1, GSTP1, and GSTT1 using PCR-based methods. Associations of genotypes and breast cancer were evaluated in logistic regression models. Meta-analysis odds ratios (ORs) were estimated using a fixed effects model. RESULTS: In the case-control study, associations were null for GSTM1 [age-adjusted OR 0.97, 95% confidence interval (CI): 0.82-1.14] and GSTT1 (OR 0.97, 95% CI: 0.83-1.15). A significant increase in risk was observed among homozygotes for the variant Ile(105)Val polymorphism (OR 1.92, 95% CI: 1.21-3.04). No combined effects of GSTM1, GSTP1, and GSTT1 genotypes or interactions with potential effect modifiers were detected. All results were similar in pre- and postmenopausal women and for early versus advanced stage breast cancer. The meta-analysis, based predominantly on Caucasian women, supported null results for the homozygous deletion variant in GSTM1 (summary OR 1.05; combining 19 studies) and GSTT1 (summary OR 1.11; 15 studies). Meta-analysis results for the homozygous GSTP1 variant indicated no overall association (summary OR 1.04; 10 studies), although results varied significantly across studies (P = 0.009). CONCLUSIONS: This large case-control study provides strong support for earlier studies showing no overall association of the GSTM1 and GSTT1 deletion polymorphisms with breast cancer risk. The GSTP1 variant may be relevant to breast cancer risk in Asian populations. 相似文献
994.
卵巢癌高频转移细胞模型中nm23-H1基因表达的相关性研究 总被引:1,自引:0,他引:1
目的 筛选高频转移卵巢恶性肿瘤细胞,研究不同转移潜能的细胞和nm23的相关性。方法 通过反复动物接种和体外培养,观察动物肺转移状况,筛选高频转移细胞株,比较原发肿瘤和转移肿瘤的特征,并应用Northera-blot方法测定各类肿瘤细胞nm23 mRNA表达水平。结果 8株卵巢恶性肿瘤细胞中4株有较高转移潜能。多次培养接种可筛选出高频转移细胞亚群。测定各类细胞nm23 mRNA表达水平与肿瘤转移特性呈负相关。结论 由基因分子水平决定的肿瘤转移趋势在不同肿瘤种类及细胞亚群中有明显差异;卵巢癌中nm23 mRNA和蛋白的表达与其转移能力的降低有密切关系,可作为判定卵巢癌预后的敏感指标。 相似文献
995.
肾恶性横纹肌样瘤临床病理分析及超微结构观察 总被引:3,自引:0,他引:3
目的:探讨肾恶性横纹肌样瘤(MRTK)的临床病理表现及超微结构特点。方法:用光镜、免疫组化及电镜等方法观察其病理组织学特点、免疫组化表达及超微结构。结果:光镜的典型特点是肿瘤细胞弥漫性排列,呈圆形、椭圆形及不规则形,胞质丰富,嗜酸性,部分胞质内可见透明状小体,细胞核圆形或椭圆形,核膜厚,核仁清楚,有的细胞核呈空泡状。部分核偏向一侧似浆细胞样。细胞内外见红染的包涵体。免疫组化显示肿瘤可表达多种抗原。电镜观察特异性表现是胞质内见中间丝及圆形不规则形纤维状或轮状小体。结论:肿瘤细胞弥漫排列呈浆细胞样,免疫组化多方向表达,可向神经性、上皮性、肌性等方向分化。电镜下胞质内中间丝及纤维轮状小体是特异性诊断标志。 相似文献
996.
ChangmingGao TakezakiToshiro JianzhongWu JianhuoDing YantingLiu SupingLi PingSu XuHu TianliongXu HamajimaNobuyuki TajimaKazuo 《中国肿瘤临床(英文版)》2004,1(3):162-166
OBJECTIVE To study the relation among methylenetetrahydrofolate reductase (MTHFR) C677T genotypes, dietary habits and the risk of stomach cancer (SC).METHODS A case-control study was conducted with 107 cases of SC and 200 population-based controls in Chuzhou district, Huaian, Jiangsu province, China. The epidemiological data were collected, and DNA of peripheral blood leukocytes was obtained from all of the subjects..MTHFR genotypes were detected by PCR-RFLP. RESULTS (1) The prevalence of the MTHFR C/T or T/T genotypes was found to be significantly different between controls (68.5%) and SC cases (79.4%,P=0.0416), the increased risk had an adjusted OR of 1.79 (95?:1.01-3.19). (2) Among subjects who had a low intake of garlic or Chinese onion, MTHFR C/T or T/T genotypes significantly increased the risk of developing SC. Among non-tea drinkers or among subjects who had a frequent intakeof meat, the carriers of the MTHFR C/T or T/T genotypes had a higher risk of SC than individuals with the C/C type MTHFR. CONCLUSION The polymorphism of MTHFR C677T was associated with increased risk of developing SC, and that individuals with differing genotypes may have different susceptibilities to SC, based on their exposure level to environmental factors. 相似文献
997.
Population-based case-control study of CYP11A gene polymorphism and breast cancer risk. 总被引:9,自引:0,他引:9
Wei Zheng Yu-Tang Gao Xiao-Ou Shu Wanqing Wen Qiuyin Cai Qi Dai Jeffrey R Smith 《Cancer epidemiology, biomarkers & prevention》2004,13(5):709-714
The CYP11A gene encodes the cholesterol side-chain cleavage enzyme (P450scc) that catalyzes the first and rate-limiting step for the biosynthesis of sex hormones. A pentanucleotide repeat [(TAAAA)n] polymorphism in the 5' of the CYP11A gene has been reported to be related to the risk of polycystic ovary syndrome, an inherited endocrine disorder characterized by hyperandrogenemia. We investigated the association of this polymorphism with breast cancer risk in a population-based case-control study conducted among Chinese women in Shanghai. Genotype assays were completed for 1015 incident breast cancer cases and 1082 community controls. Three common alleles with 4, 6, or 8 TAAAA repeats were identified in the study population. The frequency of the 8 repeat allele was more common in cases (12.6%) than controls (8.5%) (odds ratio = 1.6, 95% confidence interval = 1.3-1.9; P < 0.0001). Compared to subjects who did not carry this allele, adjusted odds ratios were 1.5 (95% confidence interval = 1.2-1.9) and 2.9 (1.3-6.7) (P for trend, <0.001), respectively, for those who carried one and two copies of this allele. This positive association was observed in both pre- and postmenopausal women and all strata defined by major breast cancer risk factors, including years of menstruation, body mass index, and waist-to-hip ratio. The results from this study indicate that the TAAAA repeat polymorphism near the promoter region of the CYP11A gene may be an important susceptibility factor for breast cancer risk. 相似文献
998.
999.
1000.
目的 探讨 CC趋化因子受体 5 (CCR5 )是否介导食管上皮炎性病变与其癌变过程的关系。方法 用免疫组化检测 40例食管鳞状细胞癌 (SCC)、癌旁炎症、不典型增生组织及 10例正常食管黏膜的 CCR5表达情况。结果 食管 SCC的 CCR5表达阳性率高于正常黏膜、慢性炎症及不典型增生的表达率 (P<0 .0 5 )。在 CCR5表达阳性的食管 SCC中 ,癌间质的单核淋巴细胞 CCR5阳性表达率分别低于癌旁炎症的单核淋巴细胞 CCR5阳性表达率(P<0 .0 5 )。结论 CCR5在食管癌变进程中表达呈升高趋势 ,提示食管 SCC细胞可能通过表达 CCR5受体与间质浸润的单核细胞、淋巴细胞共同竞争趋化因子配体 ,从而实现了食管 SCC发生进程的免疫逃逸现象 相似文献