| 1 | Speciation and fractionation of heavy metals in soil experimentally contaminated with Pb, Cd, Cu and Zn together and effects on soil negative surface charge显示文摘Speciation and fractionation of heavy metals in soil subsamples experimentally loaded with Pb, Cd, Cu and Zn in orthogonal design was investigated by sequential extraction, and operationally defined as water soluble and exchangeable(SE), weakly specific adsorbed(WSA), Fe and Mn oxides bound(OX) and organic bound(ORG). The results showed that fractions of heavy metals in the soil subsamples depended on their speciation. About 90% of Cd and 75% of Zn existed in soil subsamples in the SE fraction. Lead and Cu existed in soil subsamples as SE, WSA and OX fractions simultaneously, although SE was still the major fraction. Organic bound heavy metals were not clearly apparent in all the soil subsamples. The concentration of some heavy metal fractions in soil subsamples showed the good correlation with ionic impulsion of soil, especially for the SE fraction. Continuous saturation of soil subsamples with 0.20 mol/L NH 4Cl, which is the first step for determination of the negative surface charge of soil by the ion retention method, resulted in desorption of certain heavy metals from the soil. It was found that the percentage desorption of heavy metals from soil subsamples depended greatly on pH, the composition and original heavy metal content of the soil subsamples. However, most of the heavy metals in the soil subsamples were still be retained after multiple saturation. Compared with the parent soil, the negative surface charge of soil subsamples loaded with heavy metals did not show difference significantly from that of the parent one by statistical analysis. Heavy metals existed in the soil subsamples mainly as exchangeable and precipitated simultaneously. | ZHOU Dong mei, HAO Xiu zhen, TU Cong, CHEN Huai man, SI You bin (Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China. ) | 2002 | Journal of Environmental Sciences2002，14，4： | 10 |
| 2 | IFIT1 polymorphisms predict interferon-α treatment efficiency for hepatitis B virus infection显示文摘AIM To investigate the association between interferoninduced protein with tetratricopeptide repeats 1(IFIT1) polymorphisms and interferon-α(IFNα) treatment efficiency among Chinese hepatitis B virus(HBV) infection patients.METHODS Two hundred and twenty five newly diagnosed chronichepatitis B(CHB) patients were enrolled in the study. All of these patients received IFNα treatment for a course of 48 wk, and were followed up for 24 wk after the treatment was end. Clinical information about virological response, hepatitis B e antigen(HBe Ag) seroconversion rate and combined response at the end of the treatment, as well as the sustained response by the time of following up 24 wk after the treatment, was collected. Four tag-single nucleotide polymorphisms(SNPs) of IFIT1 were selected and assessed for their association with these clinical outcomes.RESULTS At the end of the treatment, HBe Ag seroconversion was observed in 27.1% patients. Thirty-six point nine percent patients achieved virological response, and 15.6% patients exhibited combined response. Sustained response was obtained in 26.2% patients. The main HBV genotype of the study was genotype B. Patients who infected with HBV genotype B or C showed better treatment efficiency, no matter which clinical outcome was considered. Among the four SNPs assessed, rs303218(A > G) was found to be significantly associated with the end point virological response when assuming additive model [OR = 0.64(95%CI: 0.42-0.96), P = 0.032]. Patients who carried rs303218 GG genotype had a rather higher rate of achieving virological response(response rate: 52%, OR = 0.40, 95%CI: 0.18-0.91; P = 0.028) when compared to those had AA genotype(response rate: 27%). The most significant interaction was observed in patients who had relative lower baseline aspartate transaminase. No association between SNPs and HBe Ag seroconversion, combined response or sustained response was observed.CONCLUSION IFIT1 involves in the regulation of IFNα treatment for CHB and its polymorphism rs303218 can predict the end point virological response. The finding requires further validation. | Dong-Ying Xie Shi-Ming Wang Jing-Min Yang Liang-Hui Wang Hong-Yan Chen Cong Huai Jia Shang Qing Mao Chun-Liang Lei Guang-Han Luo Ji Qian Da-Ru Lu | 2016 | World Journal of Gastroenterology2016，22，44： | 2 |
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