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11.
目的:建立电感耦合等离子体质谱法测定酒石酸长春瑞滨中有害元素及催化剂银残留的方法。方法:用微波消解处理样品,电感耦合等离子体质谱内标法测定银、钒、铬、钴、镍、铜、砷、钼、镉、锡、锑、钡、铅、汞的含量。结果:上述14种元素的方法检出限分别为0.003、0.020、0.141、0.069、0.077、0.362、0.031、0.057、0.022、0.078、0.017、0.724、0.095、0.005 ng·mL-1,线性关系良好(r≥0.9988),回收率为86%~110%,RSD小于15%;同时,给出了此方法各元素的不确定度评定程序。结论:本方法采用在线加内标,可有效校正仪器漂移,抑制基体干扰,提高准确率,多元素测定便捷、准确、灵敏、可靠,可用于酒石酸长春瑞滨中有害元素及催化剂银残留的测定。  相似文献   
12.
Cadmium (Cd) is one of the environmental risk factors for bone loss. The present study included 40 sewage workers occupationally exposed to Cd. Forty nonexposed men were included as a control group. Current smokers represented 65% and 47.5% of the exposed and control groups, respectively.

The study aimed to investigate the hazard of occupational Cd exposure on bone health. This was achieved through measuring serum and urinary Cd, and calcium (Ca), in addition to serum osteoprotegerin (OPG) and estrogen receptor-α gene. Results showed significant elevation in serum Cd, OPG, and urinary Ca levels in the exposed compared to the controls. Bony aches and joint pain were more prevalent among the exposed workers. Serum and urinary Cd increased in exposed smokers relative to control smokers. Also, serum OPG levels showed significant rise among exposed smoker and nonsmoker compared to control smoker and nonsmoker groups. Serum Cd level increased significantly in PP and pp genotypes in exposed workers compared to controls, while elevated levels of serum OPG was observed in PP and Pp genotypes in exposed workers relative to controls.

Urinary Cd exhibited significant rise in both PP and pp genotypes in exposed workers, while Ca excretion was elevated in pp genotype only. The study reflected an association of genetic predisposition and Cd exposure in progression of osteoporosis. Further research is needed to explain the mechanisms of Cd impact on bone. The role of smoking is important and hence smoking cessation programs are essential for sewage workers.  相似文献   

13.
The joint toxicity of chemicals mixture in the aquatic environment was still not well clear. To clarify the joint toxicity of the mixtures of metals and organic pollutants, as well as the influence of dissolved organic matter (DOM) in field water-body on their toxic effects, we conducted the toxicity tests with cadmium (Cd) and sodium dodecyl benzene sulfonate (SDBS) on Scenedesmus obliquus (S. obliquus) with or without the presence of fulvic acid (FA), a typical of DOM. Our results showed Cd was more toxic to S. obliquus than SDBS, and the effects of fulvic acid on SDBS were greater than Cd. The joint toxicity of Cd and SDBS expressed a synergistic effect on S. obliquus, which was observed to be increased with the presence of FA. Our results gave an example for the joint toxicity investigations of organics and metals, aiding to understanding the toxicity of pollutant mixtures in field water bodies containing DOM.  相似文献   
14.
石墨炉原子吸收法测定粟米草中铅和镉含量的研究   总被引:1,自引:0,他引:1  
目的 运用石墨炉原子吸收光谱法测定粟米草中Pb、Cd微量元素的含量.方法 通过对样品消解方法及仪器参数进行优化,建立了粟米草中Pb、Cd的石墨炉原子吸收光谱测定方法.结果 重金属元素Pb、Cd的含量,分别为3.027,1.021 μg·kg~(-1);加标回收率分别为97.25% 和100.03%.结论 实验建立的石墨炉原子吸收光谱条件用于测定粟米草中微量元素简单、快速、灵敏、准确,可为其他中药的Pb、Cd的测定提供参考.  相似文献   
15.
目的:采用电感耦合等离子体质谱(ICP-MS)法测定香芍软胶囊(XSSC)囊心物中砷、汞、铅、镉、铜的含量。方法:样品经微波消解,以Re为内标,以茶叶、圆白菜标准物质为质控,采用ICP-MS测定上述5种元素。结果:对于所测5种元素,标准曲线的相关系数r(0.9996,回收率为95.8~101.6%,RSD(5.8%。结论:本测定方法快捷、准确、灵敏度高,适用于XSSC囊心物中上述5种元素的同时测定。  相似文献   
16.
碰撞池ICP-MS技术在血中铅、砷、镉快速测定中的应用   总被引:1,自引:0,他引:1  
目的建立八极杆碰撞池电感耦合等离子体质谱(ORS-ICP-MS)快速测定血中铅、砷、镉的测定方法。方法血样经HNO,聚四氟乙烯压力罐消解体系消解后,用八级杆碰撞池电感耦合等离子体发射质谱法同时测定血样中铅、砷、镉含量。结果灵敏度高,各元素检出限在0.13-0.52μg/L之间;线性良好,线性相关系数均≥0.999;重现性好,变异系统RSD〈5%;准确度高,与标准检验方法原子吸收光谱法比对结果相对偏差〈10%,用美国威斯康星州立卫生实验室PT(Proficiency testing progam)项目组提供的标准牛血样品(编号:02Pb38)作为标样质控,分析结果与标准值合。结论本方法快速灵敏,精密度及准确度均符合要求,结果令人满意。  相似文献   
17.
The association between total cadmium (Cd) intake and abnormal urinary findings was investigated in the Cd-polluted Jinzu River basin. In 1967 and 1968 the most systematic and large-scale health examinations were conducted among the entire population aged over 30 years of this region. We performed this study by targeting the subjects participating in the 1967 health survey conducted mainly in the heavily polluted area. From subjects who had eaten household rice of known Cd concentration, 1,075 inhabitants who had either resided in their current household since birth or who had moved there from a non-polluted area (group A), and 780 inhabitants who had resided in the current household since birth (group B), were selected as the target population. The total Cd intake for each person was calculated from the Cd dose ingested from rice and other foods. Logistic regression analysis was performed using the prevalence of abnormal urinary findings (proteinuria, glucosuria and proteinuria with glucosuria) as the criterion variable and the total Cd intake and age as explanatory variables. In subjects of groups A and B the odds ratios became higher as the dose of total Cd intake increased. Odds ratios in subjects of group A were statistically significant except for glucosuria of men and proteinuria of women. In subjects of group B the odds ratios were also significant for proteinuria + glucosuria of men and glucosuria of women. It was demonstrated that the greater the increase in total Cd intake, the greater the increase in abnormal urinary findings in the Jinzu River basin, and the association of the two factors was very close.  相似文献   
18.
铅、汞、镉污染对动物健康的危害   总被引:3,自引:0,他引:3  
本文综述了铅、汞、镉污染对动物健康的危害,包括铅、汞、镉污染的来源,动物铅、汞、镉中毒的表现、监测,动物性食品中铅、汞、镉容许量以及防治措施。  相似文献   
19.
The surface expression of CD117 antigen (c-kit) on plasma cells from 158 multiple myeloma (MM), 12 plasma cell leukemia (PCL), 7 MGUS, 7 IgM lymphoplasmacytic lymphoma patients and 10 healthy subjects has been analyzed by flow cytometry using triple staining with the monoclonal antibodies CD138, CD117 and CD38. The antigen expression intensity was calculated as relative fluorescence intensity (RFI) and for direct quantitative analysis the QuantiBRITE test (Becton Dickinson) was applied. Antibody bounding capacity (ABC) was calculated using QuantiCALC software. CD117 antigen was present in 49/158 MM, 5/12 PCL and 5/7 MGUS patients. The RFI values ranged from 0.2 to 20.2 in particular MM patients (mean: 11.0 ± 5.3; median 11.5) while the number of CD117 binding sites (ABC) on MM plasma cells ranged from 637 to 6217 (mean: 3029 ± 1568; median 2946) (r = 0.8328). In responsive to chemotherapy c-kit positive MM patients the percentage of CD117 +  plasma cells in the bone marrow decreased significantly while in c-kit negative MM patients the percentage of CD117 +  cells in bone marrow did not change and remained in the normal limits. When comparing the clinical and biological disease characteristics (monoclonal protein isotype, albumin, β2-microglobulin, lactate dehydrogenase, stage of disease, response to chemotherapy, survival time) of c-kit positive and c-kit negative cases, no significant differences were found. In CD117 positive PCL cases expression of CD117 was detected in bone marrow plasma cells as well as in peripheral blood plasma cells. Normal plasma cells and those in IgM lymphoplasmacytic lymphoma did not show reactivity for the CD117 antigen. We conclude that it may be rationale to consider usefulness of therapy with tyrosine kinase inhibitors in the management of c-kit positive plasma cell proliferations. In one third of MM and PCL patients c-kit antigen could be considered as a "tumor associated marker" and together with CD38 and CD138 it may be of value for the identification of the malignant clone in minimal residual disease as it was first suggested by Spanish authors.  相似文献   
20.
CD4+CD56+ neoplasia is a rare malignancy of unclarified origin. So far only 57 cases have been reported. We characterized in detail a case of CD4+ CD56+ malignancy with special emphasis on apoptosis induced by cytotoxic drugs and expression of sialyl Lewis X (CD15s). The disease was diagnosed in a 73-year-old female presenting with skin involvement, generalized lymphadenopathy and bone marrow infiltration. Treatment with cladribine/mitoxantrone induced a short-lasting partial response and the patient died 6 months after diagnosis. The neoplastic cells expressed CD4, CD56, HLA-DR, and CD15s. PCR for the T-cell receptor γchain revealed a polyclonal amplification product. In situ hybridization for Epstein-Barr Virus (EBV) was negative. Cytotoxic granule-associated proteins were not detected, consistent with the observation that the cells did not mediate cytotoxic activity against several target cells. Apoptosis of the tumor cells was inducible by anthracyclines and cladribine but not with gemcitabine. Combinations of cladribine or gemcitabine with anthracyclines however, resulted in synergistic effects on apoptosis. Expression of CD15s on the CD56+ cells was three times higher than on CD56+ cells from healthy controls. The results demonstrate that the features of the present case is in accordance with the diagnosis of CD4+ CD56+ malignancy. This is the first report demonstrating increased CD15s expression on a CD4+ CD56+ neoplasia, possibly explaining the frequent occurrence of the disease in the skin.  相似文献   
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