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71.
72.
Caiyun Hou Sen Qiao Yue Yang Jiti Zhou 《Frontiers of Environmental Science & Engineering》2019,13(6):92
73.
Zhang Jin Wang Kun Yi Qitao Pei Yu Hou Chuanying Yi Yujun 《Environmental science and pollution research international》2021,28(24):31151-31162
Environmental Science and Pollution Research - The estuarine delta of the Yellow River is a region of strong land-ocean-human interactions that undergoes a unique evolutionary process. The delta is... 相似文献
74.
Weixuan Zhao Liping Lian Xingpeng Jin Renxi Zhang Gang Luo Huiqi Hou Shanping Chen Ruina Zhang 《Frontiers of Environmental Science & Engineering》2020,14(2):20
75.
Linsheng Yang Peter J. Peterson W. Peter Williams Wuyi Wang Shaofan Hou Jian’an Tan 《Environmental geochemistry and health》2002,24(4):293-303
Associations between the concentration of arsenic naturally occurring in drinking water and the development of skin lesions in people have been documented for some years at various locations around the world. Data on the exposure-response relationship between concentrations of arsenic in drinking water and prevalence of skin lesions in farmers from five locations in Inner Mongolia, China have been collected from the original publications and re-analysed together as a meta-study. The calculated data show a positive linear exposure-response relationship without a threshold. The reasons for this linear correlation are discussed and compared with the data from Xinjiang, another arsenism area located in a different geographical area of China. Here a different relationship was recorded that involved a threshold concentration before skin lesions developed. The significance of these two different exposure-response scenarios is discussed. 相似文献
76.
Effects of Selenium Supplementation on Arsenism: An Intervention Trial in Inner Mongolia 总被引:1,自引:0,他引:1
Linsheng Yang Wuyi Wang Shaofan Hou Peter J. Peterson W. Peter Williams 《Environmental geochemistry and health》2002,24(4):359-374
This paper reports the effects of a placebo-controlled Se-enriched yeast supplementation trial, conducted for 14 months, on arsenism in adult farmers living in a rural community in Inner Mongolia, China. The farmers had been naturally exposed to elevated concentrations of As in drinking water from tube-wells since 1983 but changed to arsenic-free drinking water when the trial began in June 1996. Blood and hair Se and As concentrations were analysed pre-intervention and at the end of the 3rd, 9th and 14th month, while skin lesions were assessed pre-intervention, as well as at the end of the 14th month, using the Arsenism Clinical Criteria established by the Ministry of Health, China. As the trial was a voluntary one, a number of farmers did not routinely have their blood and hair samples taken for analysis. Consequently, the data have been analysed in two categories. Fifty-four farmers from the Se-group and 29 from the placebo-group who were sampled on each occasion were considered as one group, which has been compared with the second group comprising up to a total of 100 farmers in the Se-group and 86 in the placebo-group. Results calculated for those farmers who were sampled on each occasion, showed that at the end of the trial, blood and hair Se concentrations of the Se-group increased from 0.130 to 0.186 µg ml–1 and from 0.431 to 0.502 µg g–1, respectively, while those of the placebo-groups remained constant. Blood and hair As concentrations of the Se-group decreased from 0.051 to 0.015 µg ml–1 and from 2.57 to 0.680 µg g–1, respectively, a greater reduction than those in the placebo-group that went from 0.064 to 0.024 µg ml–1 and from 2.62 to 1.25 µg g–1, respectively. When the data from all patients were examined, the analytical trends were similar. An evaluation of skin lesions in the category who were sampled for hair and blood on each occasion showed that 41.2% of hyperkeratosis, 50.0% of depigmentation and 44.7% of pigmentation in the Se-group improved one or more degrees, while those in the placebo-group improved by only 7.1, 12.0 and 6.7%, respectively. A total of 61.1% of the adults in Se-group improved in one or more type of skin lesion, but only 17.2% improved in the placebo-group. Comparable results were obtained when all the data from both categories of farmers were examined. Results from the trial showed that Se supplementation was more effective for the improvement of adults who were affected by double or triple skin lesions. In the placebo-group, most of the severely affected adults improved in only one kind of skin lesion, but in the Se-group, more adults improved in two or three kinds of skin lesions. Although the trial was limited by its relatively small size, the results have provided some evidence of the usefulness of Se supplementation for people affected by arsenism. 相似文献
77.
Linsheng Yang Wuyi Wang Shaofan Hou W. Peter Williams Peter J. Peterson 《Environmental geochemistry and health》2002,24(4):337-348
The clinical skin lesions of arsenism in men and women in Bayinmaodao rural district in Inner Mongolia, Peoples Republic of China, have been examined by doctors, and their hair and drinking water samples analysed for arsenic by hydride generation and ICP-AES. Altogether 311 arsenism patients with a 15.53% prevalence rate for the district were recorded. The disease prevalence rate was positively related to population, age, and their exposure to elevated arsenic concentrations in the drinking water from 1983 when new wells were dug and drinking of surface water was abandoned. Hyperkeratosis was the most serious skin lesion with the highest occurrence rate, then depigmentation and pigmentation in decreasing order. With increasing severity of the disease, ranging from skin lesion with single hyperkeratosis 1° to hyperkeratosis 3° with depigmentation 3° and pigmentation 3°, the results showed that arsenic concentrations in head hair had increased. Arsenic concentrations in hair were positively correlated with the arsenic concentrations in drinking water obtained from local wells. 相似文献
78.
白菜叶绿体DNA快速提取及分析 总被引:1,自引:0,他引:1
采用SDS-蛋白酶法提取了白菜的叶绿体DNA.琼脂糖电泳及紫外分光光度分析表明,所提取的叶绿体DNA质量高,除cpDNA主环外,在胞质雄性不育新种质及原不育系中还存在约1375bp和831bp的两条质粒分子.用所提取的叶绿体DNA作为模板进行RAPD扩增,获得了清晰的扩增图谱.该方法与传统的提取方法相比省时、高效、无污染.图2表1参14 相似文献
79.
开发沸石矿用于农业的经济评价 总被引:2,自引:0,他引:2
我国沸石矿资源丰富。开发利用沸石矿于农业,可增产粮食400亿公斤,加上节约化肥和用作饲料添加剂等方面,年经济效益为496.25亿元。因此,开发利用沸石矿于农业具有重大的经济意义,从促进我国粮食生产上新台阶的角度考虑,则具有重大的战略意义。 相似文献
80.
氨氧化细菌(AOB)和氨氧化古菌(AOA)是驱动土壤氨氧化过程的"引擎".氨氧化过程在土壤氧化亚氮(N2O)和一氧化氮(NO)排放过程中扮演着重要角色.有机无机肥配施是实现化肥零增长和作物稳产增产的重要途径,但在有机无机肥配施下,菜地土壤AOB和AOA对氨氧化过程的相对贡献仍不清楚.本研究采用选择性抑制的方法(辛炔和乙炔)区分有机肥添加近3年后(2016年10月—2019年5月)AOB和AOA在氨氧化过程中对碱性菜地土壤N2O和NO产生的相对贡献.试验共设5种施肥处理:不施氮肥(CK)、单施尿素(N)、单施有机肥(M)、50%尿素+50%有机肥(M1N1)和80%尿素+20%有机肥(M1N4).结果表明,有机无机肥配施(M1N1和M1N4)可显著增加土壤电导率、有机碳和全氮含量.培养试验发现,与N处理相比,M和M1N1处理分别使N2O排放量增加100.7%和38.8%,NO排放量增加77.9%和42.8%,AOB基因丰度增加16.6%和10.2%,同时,AOB对N2O排放的相对贡献增加6.5%.相反,M1N4处理分别使N2O和NO排放量降低19.3%和4.8%,AOB基因丰度降低37.5%,同时,AOB对N2O及NO排放的相对贡献分别降低7.8%和7.4%.相关分析表明,土壤N2O和NO累积排放量与土壤AOB基因丰度呈显著正相关(p<0.05),与土壤AOA基因丰度无显著相关性.有机无机肥配施下AOB是氨氧化过程的主要驱动者,适当比例的有机无机肥配施(即M1N4)措施可在一定程度上减弱AOB对碱性菜地土壤N2O及NO排放的相对贡献. 相似文献