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171.
Fumonisins as a possible contributory risk factor for primary liver cancer: A 3-year study of corn harvested in Haimen, China, by HPLC and ELISA 总被引:13,自引:0,他引:13
Y. Ueno K. Iijima S.-D. Wang Y. Sugiura M. Sekijima T. Tanaka C. Chen S.-Z. Yu 《Food and chemical toxicology》1997,35(12):1143-1150
Employing HPLC fluorometry, gas-liquid chromatography (GLC) and a novel enzymelinked immunosorbent assay (ELISA) based on a monoclonal antibody, 40 corn samples, each collected in 1993 from agricultural stocks for human consumption in Haimen (Jiangsu County) and Penlai (Shandong Province), high- and low-risk areas for primary liver cancer (PLC) in China, respectively, were analysed for fumonisins (FBs), aflatoxins (AFs) and trichothecenes. Levels and positive rates of FBs and deoxynivalenol (DON) were significantly higher in Haimen than in Penlai. ELISA of the 40 corn samples harvested in the two areas in 1994 revealed that FB contamination levels and rates in these areas were comparable to those observed in 1993 in Haimen. ELISA analysis of 1993 and 1994 products revealed a wide occurrence of AFB1 but the positive rates as well as levels were not significantly different between these areas. ELISA of the same sample number of corn harvested in 1995 revealed that FB contamination in Haimen was significantly higher than in Penlai. These 3-yearly surveys of corn samples (240 in total) demonstrated that corn harvested in Haimen was highly contaminated with FBs and that the contamination level, as well as positive rate in 1993 and 1995, were 10–50-fold higher than those in Penlai, suggesting FBs as a risk factor for promotion of PLC in endemic areas, along with the trichothecene DON. Co-contamination with AFs, potent hepatocarcinogens, was assumed to play an important role in the initiation of hepatocarcinogenesis. 相似文献
172.
本文对煤焦沥青诱发大鼠肺癌过程中的病理形态学所见作了报道。整个过程可以分为三个阶段:1.异物反应阶段;2.异常增生和鳞状化生阶段;3.癌肿发生发展阶段。文中对每一个阶段的病理组织学改变做了详细描述。煤焦沥青诱发的大鼠肺癌的特征如下:1.癌肿全都发生在肺的周边部位;2.绝大多数癌肿的组织类型都是高分化鳞状细胞癌;3.多发性,数个至数十个大小不等的肿块布满全肺;4.癌变各个不同阶段的改变可在同一肺脏中出现;5.转移癌较少见。 相似文献
173.
174.
Tomotaka Sobue Takaichiro Suzuki Tsuguo Naruke The Japanese Lung Cancer Screening Research Group 《Cancer science》1992,83(5):424-430
A case-control study to evaluate the efficacy of lung cancer screening conducted by us showed that lung cancer screening may reduce the mortality of the disease up to 28%. Assuming this efficacy is unbiased, and that the screening rate is 51.6%, which was observed in the control group in the above study, the number of lung cancer deaths prevented by screening in the study period was calculated to be 47 for males and females combined. In the same study population, screen-detected lung cancer patients (N = 207) in the same study period were followed and the 7-year survival rate (46.9%) was compared to the 5-year survival rate (11.3%) obtained by the Osaka Cancer Registry, in which screen-detected lung cancer patients were only 1.8%. The number of lung cancer deaths prevented by screening, estimated by the difference in the above two survival rates, was 74 (95% confidence interval; 55–93). The number of lung cancer deaths prevented by screening estimated from the case-control study was significantly lower than that estimated from the survival analysis. This indicates that the efficacy of lung cancer screening estimated by the case-control study was within the range that could be explained by the actual long-term survivors among the screen-detected patients in the study population. 相似文献
175.
Localized pleural plaques and lung cancer. 总被引:1,自引:0,他引:1
T Partanen M Nurminen A Zitting H Koskinen M Wiikeri K Ahlman 《American journal of industrial medicine》1992,22(2):185-192
In a mass chest radiography survey conducted in 1971 for 7,986 residents of three Finnish communities, 604 subjects (7.6%) with pleural plaques but not other asbestos-related radiographic signs were identified. The same number of referents, each individually matched to each plaque carrier on sex, birth year, and community, was selected from among persons in the same source population with no pleural plaques. The two groups were followed for investigation of incidence of lung cancer during 1972-1989. Twenty-eight of those with plaques and 25 referents contracted lung cancer (crude conditional RR = 1.1; CL95 = 0.7, 1.9). The application of the proportional hazards model, with adjustment for sex, age, and residence, resulted in a hazard ratio of 1.1 (CL = 0.6, 1.8). The risk ratio estimate may be biased; hence, the result is inconclusive in regard to the predictive assessment of lung cancer risk among carriers of pleural plaques. 相似文献
176.
因症就诊检出早期大肠癌的临床及病理学特征 总被引:1,自引:0,他引:1
目的探讨在就诊的肛肠病人中如何提高早期大肠癌的检出率。方法在11家医院推广对肛肠病人的四项检查程序——直肠指检,乙结镜检查,大便隐血试验,和X线气钡灌肠造影。结果在4821例有肛肠症状的病人中,检出大肠癌188例,检出率为3.9%,其中180例有术后病理诊断。47/180例(26.1%)属早期癌(DukesstageA)。41/47例由上述四项检查作出初步诊断。初发症状为:(1)便血(26例,持续15.2±9.4周后就诊,肿瘤平均直径2.58cm);(2)大便习惯改变(9例,33.4±19.7周,3.39cm);(3)腹痛腹块(10例,19.2±11.2周,5.0cm);(4)贫血(2例,17.2±9.9周,4.75cm)。8/12例的A0和A1期病例属便血组,并多位于直肠。41/47例以高、中分化腺癌为主,其中15例伴有腺瘤癌变。术前曾作活检的27例中,12例未检出癌变细胞。结论四项检查对检出早期大肠癌是有效的,便血是提示早期癌最有价值的症状,加强大肠癌防治宣教,采用瘤灶多点或全瘤活检技术,高度重视大肠腺瘤和不典型增生等癌前病变,将有助于提高早期大肠癌的检出率 相似文献
177.
178.
采用放射免疫方法测定了31例大肠癌、13例非肿瘤者血清标本和20例大肠癌组织、邻近肿瘤(〈3cm)及远离肿瘤(5cm)之结肠粘膜组织匀浆标本中的胃泌素浓度。发现:Dukes C.D期大肠癌病人血清胃泌素显著高于非肿瘤者(P〈0.05);血清胃泌素浓度与病程进展呈显著正相关(P〈0.05);直肠癌病人血清胃泌素显著高于非肿瘤(P〈0.05);血清胃泌素水平与肿瘤分化程度无关;肿瘤切除后血清胃泌素显著 相似文献
179.
Mary Steidl Matsui Isabella Illarda Nianci Wang Vincent A. DeLeo 《Experimental dermatology》1993,2(6):247-256
Abstract Several lines of evidence implicate protein kinase C (PKC) in the development of basal cell and squamous cell carcinomas, tumors which originate from epidermal keratinocytes. To examine PKC in a model relevant to human skin, we exposed normal human epidermal keratinocytes (NHEK) in serum-free media to a variety of PKC agonists and antagonists. NHEK PKC activity increased up to 10-fold within the 1st hour of exposure to tetradecanoyl phorbol acetate (TPA), and gradually returned to control values within 72 h. TPA-induced PKC activity was enhanced by pretreatment of cultures with protein and RNA synthesis inhibitors. TPA-induced growth arrest and differentiation was antagonized by staurosporine. Down-regulation by bryostatin pretreatment blocked TPA-stimulated differentiation. Our overall conclusion is that activation of PKC in cultured human keratinocytes is required for differentiation. These results are crucial to the analysis of compounds suspected of promoting or inhibiting epidermal tumors. 相似文献
180.
Streptococcus sanguis, usually considered a nonpathogen of the oral cavity, was isolated from blood cultures from a patient who was subsequently found to have a cecal adenocarcinoma. Further studies are needed to determine if Streptococcus sanguis infections have diagnostic implications similar to those of Streptococcus bovis. © 1995 Wiley-Liss, Inc. 相似文献