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21.
Determination of trace selenium in human body by anodic stripping voltammetry at gold-disc electrode
Summary For determination of trace Se we used high-pressure wet digester to pretreat the specimens obtained from the human body. This
method is very effective in preventing loss of Se by volatilization which often occurs in the sample pretreatment. We studied
the method of using anodic stripping voltammetry at gold-disc electrode to measure the trace Se present in the human body
and found it to be the optimal procedure. The detection limitation was about 2x10−8 g/L, the recovery rate of Se about 96.6±6,7 %
, and the coefficient of variation CV = 7.0%. 相似文献
22.
Summary The level of selenium in blood serum was determined in 33 patients with breast cancer, 13 women with verified mastopathy, and 43 healthy subjects from the Zagreb area. In the second and third quartiles the values of selenium obtained from sick subjects (41–58µg/L) and healthy subjects (73–89µg/L) differed significantly (P < 0.001). In the group of subjects with mastopathy, serum selenium in the same way ranged from 67–76µg/L and did not differ significantly from the group of healthy women, but differed significantly from the patients with breast cancer (P < 0.001).Such a result leads to the conclusion that determination of selenium in the blood could be used as a non-invasive diagnostic parameter in clinical assessment of malignant breast disease. 相似文献
23.
应用单细胞凝胶电泳研究了一定剂量的亚硒酸钠对离体和在体大鼠肝细胞 DNA损伤的作用。结果表明 :在2 .185、 4.375、 8.75 0、 17.5 0 0、 35 .0 0 0 μmol/ L 的剂量条件下 ,除 2 .185 μmol/ L 的剂量外 ,其余剂量的亚硒酸钠均可引起离体大鼠肝细胞 DNA损伤。 5、 10、 2 0 μmol/ kg的亚硒酸钠也可引起在体大鼠肝细胞 DNA损伤。亚硒酸钠引起的离体和在体大鼠肝细胞 DNA损伤均存在明显的剂量 -反应关系。研究结果提示 ,一定剂量的亚硒酸钠能引起离体和在体大鼠肝细胞 DNA损伤 相似文献
24.
Z. Lajtman D. Nosso Z. Romic K. Trutin-Ostovic D. Krpan 《European archives of oto-rhino-laryngology》1994,251(3):170-172
Blood selenium concentrations in 43 patients with laryngeal cancer and 47 normal subjects were determined by atomic absorption spectrophotometry. No significant differences in selenium values were observed in sera from the cancer patients when compared with controls, but there were significant differences between patients with advanced (T4) supraglottic cancers and the normal controls. These results suggest that lower blood selenium levels in this latter group of laryngeal cancer patients may be a consequence of their disease rather than its cause. 相似文献
25.
氟硒联合作用对大鼠精子及睾丸形态学影响的研究 总被引:1,自引:0,他引:1
目的探讨氟硒及其联合作用对大鼠精子及睾丸形态学的影响。方法采用饮水加硒(3mg/L)和食物摄氟(50mg/kg)的方法。结果加氟可使大鼠精子总数减少、存活率降低及睾丸生精过程受到轻度抑制,曲细精管管径变小等病理形态学改变。当硒氟共同作用时,上述变化均有不同程度的减轻。结论此剂量条件下的硒可拮抗慢性氟中毒所引起的生殖系统的变化。 相似文献
26.
目的:为了解空勤与地勤人员的硒摄入,吸收和排泄量,以及硒代谢的差异,进一步做好空勤与地勤人员的营养保障,方法:用双盘法在3d自由进食条件下对36名空勤人员进行了硒代谢平衡的研究,并以36名地勤人员作为对照,结果:空勤组的硒摄入量(59.85μg.d^-1)尿硒排泄量(30.84μg.d^-1),表现吸收量(39.27μg.d^-1)和全血硒(98.91ng.ml^-1)均高于地勤组(45.96μg 相似文献
27.
Tissue potassium,selenium, and iron levels associated with gastric cancer progression 总被引:4,自引:0,他引:4
Chew-Wun Wu MD Yuan-Yaw Wei BS Chin-Wen Chi PhD Wing-Yiu Lui MD Fang-Ku P'eng MD Chien Chung PhD 《Digestive diseases and sciences》1996,41(1):119-125
The contents of 10 minor and trace elements in histologically confirmed gastric adenocarcinomas and their corresponding normal gastric mucosal tissues obtained from 39 patients at the time of gastric resection were simultaneously determined by instrumental neutron activation analysis. Specimens were irradiated by reactor neutrons and subsequently subject to direct analysis using a high-resolution HPGe -spectrometer. Univariate analysis revealed that gastric cancer tissues had significantly higher concentrations of Fe, K, Mg, Na, Rb, Se, and Zn than normal gastric mucosal tissues. However, multivariate analysis found that Fe, K, and Se were independent elements that associated with gastric cancer. Upon further evaluation of their clinical significance, we found a high tissue K level was related to lymphatic duct metastasis. High Se tissue levels were linked to intestinal type adenocarcinoma. A positive correlation was found between high Fe levels and vascular involvement. These findings suggest that Fe and K are associated with gastric cancer progression. Se is involved in carcinogenesis of stomach in high-risk areas. The mechanisms that underlie the corresponding pathohistological features deserve further study. 相似文献
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30.
采用中药加服微量元素Se治疗慢性肝炎85例,并与单用中药治疗40例作对照。结果:治疗组显效54例,有效25例,无效6例,总有效率为92.94%;对照组显效9例,有效26例,无效5例,总有效率为87.50%;观察组显效例数与对照组比较有显著意义(t=3.828,P<0.001)。 相似文献