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941.
A case-control study of diet and the risk of ovarian cancer. 总被引:3,自引:0,他引:3
Sai Yi Pan Anne-Marie Ugnat Yang Mao Shi Wu Wen Kenneth C Johnson 《Cancer epidemiology, biomarkers & prevention》2004,13(9):1521-1527
Epidemiologic studies have suggested that some dietary factors may play a role in the etiology of ovarian cancer, but the findings have been inconsistent. We assessed the association of ovarian cancer with dietary factors in a population-based case-control study in Canada. Diet information was collected on 442 incident cases of ovarian cancer diagnosed in 1994 to 1997 and 2,135 population controls via a self-administered questionnaire. Compared with women in the lowest quartile of cholesterol intake, those in the second, third, and fourth quartiles had a multivariate adjusted odds ratio [OR; 95% confidence interval (95% CI)] of 1.12 (0.81-1.56), 1.20 (0.85-1.68), and 1.42 (1.03-1.97), respectively (P for trend = 0.031). Higher egg consumption was also associated with a nonsignificant increase in ovarian cancer risk. The ORs (95% CIs) for ovarian cancer were 0.77 (0.60-1.04) and 0.76 (0.56-0.99) among women in the highest quartile of total vegetable and cruciferous vegetable intake as compared with women in the lowest quartile. Women who took supplements of vitamin E, beta-carotene, and B-complex vitamins for > or =10 years had ORs (95% CIs) of 0.49 (0.30-0.81), 0.31 (0.11-0.91), and 0.61 (0.36-1.05), respectively. However, we did not observe an association of ovarian cancer risk with dietary fat intake, including saturated, monounsaturated, and polyunsaturated fatty acids, protein, carbohydrate, dietary fiber, fruit, dairy products, meat products, fish, chicken, grain products, nut products, baked desserts, margarine, butter, mayonnaise, and supplement of multiple vitamins, vitamin A, vitamin C, calcium, iron, zinc, and selenium. Our findings suggested that ovarian cancer risk was positively associated with higher consumption of dietary cholesterol and eggs and inversely associated with higher intake of total vegetables and cruciferous vegetables and supplementation of vitamin E, beta-carotene, and B-complex vitamins. 相似文献
942.
Haptoglobin-alpha subunit as potential serum biomarker in ovarian cancer: identification and characterization using proteomic profiling and mass spectrometry. 总被引:24,自引:0,他引:24
Bin Ye Daniel W Cramer Steven J Skates Steven P Gygi Vanessa Pratomo Lanfei Fu Nora K Horick Larry J Licklider John O Schorge Ross S Berkowitz Samuel C Mok 《Clinical cancer research》2003,9(8):2904-2911
PURPOSE: The objective of this study was to identify and characterize new serum biomarkers in ovarian cancer patients using mass spectrometric protein profiling and specific immunological assays. Experimental Design: Serum samples from 80 cancer patients and 91 healthy women were analyzed by surface enhanced laser desorption and ionization-mass spectrometry (MS) profiling. A candidate biomarker was purified by affinity chromatography, and its sequence was determined by liquid chromatography-tandem MS. An antibody was generated from the synthesized peptide for quantitative validation in the cases and controls. CA125 was determined and compared with the same set of specimens. RESULTS: Using surface enhanced laser desorption and ionization, we found a serum biomarker at approximately 11700 Da, which had peak intensity significantly higher in cases (1.366) compared with controls (0.208, P = 0.002), and subsequently identified this as the alpha chain of haptoglobin. ELISA indicated that Hp-alpha was =2-fold higher in cancer serum compared with normal, benign tumor, and other gynecological cancers (P < 0.05) and had 64% sensitivity at 90% specificity alone and 91% sensitivity and 95% specificity if combined with CA125. CONCLUSIONS: Haptoglobin-derived alpha subunit is a potential marker for ovarian cancer that is complementary to CA125. MS-based protein profiling is a valuable tool for screening protein markers and useful to detect post-translational modification of tumor-associated proteins or abnormal metabolic products. However, confirmation of protein identity with specific antibodies is crucial for clinical application and functional studies. 相似文献
943.
Bin Zhang Andrei Ougolkov Kaname Yamashita Yutaka Takahashi Masayoshi Mai Toshinari Minamoto 《Clinical cancer research》2003,9(8):3073-3079
PURPOSE AND STUDY DESIGN: Recent studies have shown that beta-catenin translocated into the cell nucleus functions like an oncogene. Accumulating evidence suggests that activation of the beta-catenin oncogenic signaling cascade along with its twin, the K-ras cascade, may exert syngeneic or synergistic effects on tumor development and progression. In the study reported here, we analyzed oncogenic beta-catenin activation on the basis of its nuclear accumulation (NA) and compared the results with those of mutational activation of K-ras in 74 patients with colorectal cancer to determine whether the two oncogene-mediated signaling cascades interact. RESULTS: We found two distinct patterns of beta-catenin activation, i.e., diffuse NA in 20 cases (27%) and selective NA at the tumor invasion front (NAinv) in 19 cases (26%). The presence of the NAinv pattern was significantly correlated with advanced Dukes' stage tumor (P = 0.0005) and the presence of distant metastases (P = 0.0064). K-ras proto-oncogene was mutated in the tumors of 31 cases (42%). Activated beta-catenin or K-ras was detected in most (78%) colorectal cancers analyzed, although a weak inverse correlation was found between the activities of the two oncogenes in the tumors. Importantly, most (7 of 8) patients with tumor showing both K-ras activation and the NAinv pattern of beta-catenin activation were in Dukes' stage C at surgery, and half of them developed distant metastases to the liver and lungs. CONCLUSION: The results suggest that although oncogenic activation of beta-catenin and K-ras is independent in the process of clinical cancer development, combined analysis of the two major oncogenes can detect most colorectal cancers and identify a subset of patients with poorer outcomes. Consequently, activation of either or both of these oncogenes may serve as a genetic marker for molecular diagnosis. 相似文献
944.
金斌 《现代中药研究与实践》2003,17(5):39-41
目的 制定桔梗冬花片质量控制方法。方法 采用薄层色谱法对处方中的桔梗、甘草进行定性鉴别 ;采用高效液相色谱法对处方中甘草中甘草酸进行含量测定。结果 甘草酸在 0 .186 6~ 1.6 794 μg呈良好的线性关系 ,r=0 .99997,平均回收率为 98.70 ,RSD=0 .77。结论 该方法准确可靠地进行定性、定量检测 ,能有效地控制制剂的质量。 相似文献
945.
目的 :了解PNS单体Rbl对豚鼠心脏乳头肌动作电位和收缩力的影响。方法 :运用带有动作电位和收缩力分析软件控制的细胞内微电极技术 ,研究了三七皂苷 (PNS)单体Rbl对豚鼠正常心脏乳头肌动作电位 (AP)各特征参数及收缩力 (FC)的影响。结果 :Rb1 1 0~ 30 μmol·L- 1 分别使APD 2 0 ,APD 90明显缩短 ,FC显著下降 (P<0 .0 1 ,n =5) ,并可降低高钾诱发的豚鼠乳头肌慢反应动作电位的动作电位幅值 (APA)及零相最大上升速率(Vmax) (P <0 .0 5 ,n =5)。但对静息电位 (RP) ,APA ,Vmax及AP的超射值 (OS)无明显影响 (P >0 .0 5 ,n =5)。另外 ,Rbl可浓度依赖性地抑制乳头肌收缩力 (FC) ,RP ,APA不随Rbl剂量增加而产生明显变化 ,呈典型的兴奋 收缩脱藕联。结论 :其效应可能通过阻滞钙通道而产生 相似文献
946.
本文介绍了根癌农杆菌T-DNA对云南红豆杉原生质体的转化,分析了转化系的紫杉醇合成能力。实验以生长20 d的云南红豆杉幼茎诱导的淡黄色愈伤组织为材料,经酶解可分离出大量有活力的原生质体。在由B5无机盐、KM有机成分、3.0 mg/L 2,4-D、0.1mg/L KT和0.45 mol/L果糖组成的培养基中培养1周后,原生质体再生细胞持续分裂形成细胞团。根癌农杆菌对原生质体的转化能力与原生质体生长状态及菌株相关。虽然刚分离的或已再生细胞壁的原生质体不能被根癌农杆菌转化,但由10个以上细胞组成的原生质体克隆和根癌农杆菌B6S3菌株共培养后可实现T-DNA转化,高压纸电泳检测转化系具有冠瘿碱的合成,转化率约为5%。HPLC证实转化系具有合成紫杉醇的能力,但不同转化系中紫杉醇含量变异很大,最高含量为0.076%,是对照愈伤组织的6倍,表明T-DNA的插入改变了培养细胞对紫杉醇的合成。获得的高产转化系细胞生长比对照低,但继代培养中其生长和紫杉醇积累基本保持稳定。尽管转化系合成紫杉醇能力远未达到商业化生产的要求,但研究通过T-DNA对原生质体的转化而实现插入诱变,可以为分离高产紫杉醇优良细胞系提供单细胞筛选系统。 相似文献
947.
中药复方化学与创新药物研究 总被引:2,自引:0,他引:2
中药复方化学与创新药物研究是中药现代化研究中的关键课题,本文简要回顾了中药复方化学研究的概况,论述了中药复方化学研究的思路和方法学,结合研究实践,阐明以中药复方化学研究所发掘出的中药复方有效部位(群)或有效成分(群)为基础,研制创新药物是实现中药现代化与国际化的有效途径。 相似文献
948.
大孔吸附树脂吸附分离技术在中药复方纯化分离中的应用 总被引:2,自引:0,他引:2
中药复方有效部位(群)或有效成分(群)的提取、分离与纯化,是实现中药现代化的关键技术之一。本文综述大孔吸附树脂吸附分离技术用于中药复方有效部位(群)或有效成分(群)纯化分离的优势及应用特点。 相似文献
949.
目的 :观察国产、进口乌拉地尔对全麻拔管期心血管反应的影响。方法 :60例无高血压病史的择期全麻手术病人随机分为 3组 ,分别为国产乌拉地尔组、进口乌拉地尔组和对照组。三组病人麻醉诱导均相同。术毕当病人符合拔管指征时 ,静注乌拉地尔 0 4mg/kg ,或等量生理盐水 (对照组 )。观察记录拔管前、拔管时、拔管后 1分钟、5分钟的SP、DP、HR ,并计算SP与HR的乘积RPP。结果 :对照组拔管后SP、DP、HR、RPP均较拔管前显著升高 (P <0 0 5 ) ,尤以拔管时至拔管后 1分钟为著 (P <0 0 1)。围拔管期两组乌拉地尔组的血流动力学变化非常相似 ,SP、DP较拔管前均无明显变化 ,而HR则均明显升高 (P <0 0 5 ) ,与对照组相比SP、DP和RPP的变化均明显降低(P <0 0 1)。结论 :国产乌拉地尔与进口制剂具有同等的降压效能 ,可削弱拔管期高血压反应 相似文献
950.
J-M Luo H Yoshida S Komura N Ohishi L Pan K Shigeno I Hanamura K Miura S Iida R Ueda T Naoe Y Akao R Ohno K Ohnishi 《Leukemia》2003,17(1):1-8
The SH2 domain-containing inositol 5'-phosphatase (SHIP) is crucial in hematopoietic development. To evaluate the possible tumor suppressor role of the SHIP gene in myeloid leukemogenesis, we examined primary leukemia cells from 30 acute myeloid leukemia (AML) patients, together with eight myeloid leukemia cell lines. A somatic mutation at codon 684, replacing Val with Glu, was detected in one patient, lying within the signature motif 2, which is the phosphatase active site. The results of an in vitro inositol 5'-phosphatase assay revealed that the mutation reduced catalytic activity of SHIP. Leukemia cells with the mutation showed enhanced Akt phosphorylation following IL-3 stimulation. K562 cells transfected with the mutated SHIP-V684E cDNA showed a growth advantage even at lower serum concentrations and resistance to apoptosis induced by serum deprivation and exposure to etoposide. These results suggest a possible role of the mutated SHIP gene in the development of acute leukemia and chemotherapy resistance through the deregulation of the phosphatidylinositol-3,4,5-triphosphate (PI(3,4,5)P3)/Akt signaling pathway. This is the first report of a mutation in the SHIP gene in any given human cancer, and indicates the need for more attention to be paid to this gene with respect to cancer pathogenesis. 相似文献