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31.
甲状腺乳头状癌中砂粒体矿物学研究   总被引:5,自引:0,他引:5  
砂粒体矿化对诊断甲状腺乳头状癌具有高度的特异性,对其矿物成分及形成机理的分析有望对研究肿瘤的发生发展过程提供辅助信息.本文以甲状腺乳头状癌中的同心层状砂粒体矿化作为研究对象,采用偏光显微镜、环境扫描电镜及其能谱、傅立叶变换红外光谱、电子探针和高分辨透射电子显微镜,对原位和分离处理样品的表面形貌、结构和矿物成分进行了观察测试.研究结果表明,甲状腺乳头状癌中砂粒体是由纳米尺寸的粒状、短柱状碳羟磷灰石及一些无定形低Ca/P(原子分数,下同)的磷酸钙矿物混合组成,砂粒体的同心层状构造具有微胶粒成因的特征,是结构和成分不同的直接反映,砂粒体中Ca、P及 Ca/P的分布具有从外向内逐渐升高的趋势.  相似文献   
32.
Variation of the stable iodine supply was evaluated in the soils of around more than 700 settlements in the regions (oblasts) of Belarus and the Russian Federation contaminated after the Chernobyl accident. It involved the use of regional information on iodine content in different types of soil cover, biogeochemical criteria of iodine deficiency in food chains, and the available soil maps.  相似文献   
33.
目的:分析支气管动脉灌注化序栓塞及CT导引下注入无水乙醇超液化碘油双介入疗法治疗原发性肺癌的疗效。材料和方法:对20例原发肺癌均进行了支气管动脉灌注化疗,累计24次。其中9例在支气管动脉化疗同时进行了栓塞,共13次:单纯化疗11例,共10次。而后20例又分别进行了CT导引下注入无水乙醇的介入治疗,累计49次,其中11例为注入无水乙醇与超液化碘油混合剂,共33例。结果:支气管动脉化疗栓塞及单纯化疗的临床有效率分别为77.77%和45.45%:采用支气管动脉化疗栓塞及CT导引下注射无水乙醇的双介入疗法治疗有效率为88.88%。临床无明显不良反应及并发症。结论:双介入疗法较单独使用其中-种疗法治疗肺癌的临床有效率、生存率明显增高,有显著性差异(P<0.05)。  相似文献   
34.
本文利用岩石类型资料1092个数据,胃癌死亡调查资料10295例,研究了胃癌死亡率与人群生存区岩石类型(岩浆岩、变质岩、碳酸盐岩、碎屑岩、红色碎屑岩、第四系松散物)的相关性。在此基础上,综合评价了与胃癌有相关性的岩石类型,及其对胃癌产生和发展的影响。研究方法可供参考。  相似文献   
35.
Arsenic in drinking water has been shown to increase the risk of urothelial carcinoma and lung cancer. However, the lifetime risk of developing urothelial carcinoma and lung cancer caused by exposure to arsenic in drinking water has not been reported. This study aimed to assess the lifetime risk of urothelial carcinoma and lung cancer caused by arsenic exposure from drinking water and cigarette smoking habit for residents living in the arseniasis-endemic area in Northeastern Taiwan. We recruited 8086 residents in 1991–1994 and monitored them for their newly developed types of cancers, identified by computerized linkage with the national cancer registry profile. There were 37 newly diagnosed urothelial carcinoma cases and 223 new lung cancer cases during the follow-up period (until 2007). The lifetime (35–85 years old) cumulative risk of developing urothelial carcinoma from an arsenic concentration in the drinking water of <10, 10–99, and 100+ μg/L was 0.29%, 1.07% and 3.43%, respectively. The corresponding probabilities were 7.42%, 8.99% and 17.09% for the lifetime risk of developing lung cancer. Cigarette smoking was associated with an increased risk of urothelial carcinoma and lung cancer, showing the hazard ratio (95% confidence interval) of 2.48 (1.27–4.82) and 3.44 (2.00–5.90) after adjusting for the arsenic concentration in drinking water. After adjusting for cigarette smoking, the hazard ratio (95% confidence interval) of developing urothelial carcinoma caused by the arsenic concentration in drinking water of <10, 10–99 and 100+ μg/L was 1.0 (the reference group), 2.18 (0.59–8.01), and 8.71 (2.49–30.48), respectively. The corresponding figures were 1.0 (the reference group), 1.14 (0.80–1.61), 1.84 (1.28–2.65) for lung cancer. Synergistic effects on the development of urothelial carcinoma and lung cancer existed between the arsenic exposure level and cigarette smoking. It is suggested that people who have had a high exposure to arsenic in drinking water should stop smoking cigarettes to lower their lifetime risk of urothelial carcinoma and lung cancer.  相似文献   
36.
目的:分析囊性肾癌的CT表现,探讨多层螺旋CT的诊断价值。方法:回顾性分析11例囊性肾癌的临床表现、CT及病理资料。CT成像技术为采用64排螺旋CT平扫及三期增强扫描,并行冠状位、矢状位的多平面重建。结果:11例囊性肾癌均显示为囊性或囊实性肿块,规则或不规则,大小不一,均有囊壁增厚。其中壁结节占9例,瘤内分隔占4例,囊壁钙化占4例。囊壁及分隔厚薄不均,增强后可见囊壁、囊内分隔及壁结节的强化,主要呈"快进快出"的特征。多平面重建图像显示肿瘤细节及其与周围结构关系更加清晰。结论:囊性肾癌具有一些特征性的CT征象,多层螺旋CT多期增强扫描及多平面重建有助于明确诊断,但需与肾脏其他囊性病变相鉴别。  相似文献   
37.
本文报导了本院102例初诊鼻咽癌进行了CT检查,旨在研究放陪前鼻咽癌的CT表现及临床意义。结果发现,原发灶可发生在鼻咽后壁,侧壁及顶壁,以多个受侵为常见,半数以上闰例有咽旁间隙侵犯,41.8%的病例亦有颅底侵犯,提示NPC在确诊时约有半数并非早期,认为对有鼻咽腔症状者应及早进行鼻咽镜检查,可望提高NPC的早期确诊率。  相似文献   
38.
The Guangdong province of China contains the most clearly described high-incidence of hepatocellular carcinoma (HCC) and nasopharyngeal carcinoma (NPC) areas in the world. The geographical heterogeneity of cancer incidence in the region suggests that many carcinogenic risk factors might be present in the regional geochemical environment. This paper presents the concentrations of a wide range of known carcinogens in two high cancer incidence areas in Guangdong and compared them to a low cancer incidence area in the same province. N-Nitrosamines, NO3, NO2, and ammonium were detected in groundwater, surface water, and drinking-water. The concentrations of the 7 trace metal and metalloid elements As, Cd, Ni, Cu, Pb, Zn, and Hg were determined in surface soil samples and all water samples. The results show that, compared with the guidelines or limit values for drinking-water quality in the world, the high cancer incidence areas have hazardous high levels of N-nitrodimethlyamine (NDMA) in all kinds of water. Oppositely, the low cancer incidence area has a safe low level of NDMA in water bodies. The levels of NO3, NO2, and ammonium in water have the same character, although they have different expression between the two high-risk areas. The distribution of the 7 tested trace elements in surface soil has no significant correlation with cancer incidence. On the other hand, high concentrations of carcinogenic N-Nitrosamines in drinking-water and natural water bodies were identified for the first time in the high NPC and HCC incidence area.  相似文献   
39.
肺癌CT诊断与分析   总被引:1,自引:1,他引:0  
本文目的是探讨CT在肺癌诊断中的价值,所用的材料与方法是搜集赤峰市第六医院的肺癌病例46例,所有病例均手术病理,支气管镜检或细胞这检查证实,常规CT扫描后对选择病例在选择层面行HRCT扫描,结果得到了CT在肺癌诊断上,特别在肺癌分期上优于常规X线检查,此外,HRCT在显示细微病变或病变伪细微结构方面有重要价值,结论是CT不仅可用于肺癌诊断还可用于肺癌分期,因而更有益于临床医生制订治疗方案。  相似文献   
40.
目的是探讨乳化碘油增强CT对早期肝癌的诊断作用。方法采用乳化碘油:由碘化油、卵磷脂、甘油等经超声乳化而成:用二乙基亚硝胺诱导法建立大鼠肝癌模型(n=4):观察静脉注射乳化碘油(0.4ml/只)后,正常大鼠(n=4),及大鼠肝癌病灶的强化情况,并与病理学检查进行对照分析。结果得到:乳化碘油能引起肝脾组织特异性显著强化:透视电镜证实肝细胞参与碘油乳粒的摄取:选取的4只大鼠肝癌模型中,共有14个瘤结,大小4、5±3.4mm;乳化碘油增强CT检出率85.7%(12/14)的瘤结,明显高于平扫时,病灶显示率(14.3%)。结论为乳化碘油是一种潜在的肝脾特异性造影剂,对早期肝癌的检出具有重要价值。  相似文献   
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