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排序方式: 共有491条查询结果,搜索用时 15 毫秒
61.
[目的]获得抗Cu2+的单克隆抗体。[方法]以异硫氰酸苄基乙二胺四乙酸(ITCBE)为双功能螯合剂,使Cu2+分别与载体蛋白牛血清白蛋白(BSA)、卵清蛋白(OVA)偶联,获得免疫原(Cu-ITCBE-BSA)和检测原(Cu-ITCBE-OVA)。用非变性聚丙烯凝胶电泳鉴定偶联结果。免疫Balb/C小鼠,通过细胞融合,获得能稳定分泌抗Cu2+的杂交瘤细胞株,并通过亲和层析法纯化腹水获得抗Cu2+的单克隆抗体。[结果]获得了1株能稳定分泌抗Cu2+的单克隆抗体的细胞株(4A6),所分泌的抗体亚类为IgG1,细胞培养上清效价可达1∶1.0×103,腹水效价可达1∶6.4×105。以该细胞株接种Balb/C小鼠腹腔,获得抗Cu2+的腹水型单抗;该腹水经过亲和层析法纯化后,纯度可达95%。[结论]获得了抗Cu2+的单克隆抗体,为环境水样中Cu2+的免疫学检测奠定基础。 相似文献
62.
63.
为了研究膨润土对铜污染土壤的修复机理,通过油菜盆栽试验研究了粘土矿物膨润土对铜污染土壤酶活性的影响。结果表明:随着铜污染程度的增加,土壤脲酶、碱性磷酸酶、过氧化氢酶、硝酸还原酶的活性都受到不同程度的抑制。膨润土的施加能显著提高铜污染的土壤酶活性,土壤脲酶、碱性磷酸酶、过氧化氢酶、硝酸还原酶的活性分别提高了6.4%~15.4%、4.0%~19.3%、1.26%~1.85%和4.6%~10.9%,且对4种酶活性的增加幅度为:碱性磷酸酶>脲酶>硝酸还原酶>过氧化氢酶,并表现出在高污染下对土壤脲酶和碱性磷酸酶的增幅大于低浓度污染,在低浓度污染下对土壤过氧化氢酶和硝酸还原酶的增幅大于高浓度铜污染。说明膨润土对铜污染的土壤有一定的修复能力。 相似文献
64.
[目的]研究pH、初始铜离子浓度和吸附时间对石英砂-腐殖酸-Cupriavidus gilardii CR3复合体吸附铜离子的影响。[方法]利用等温吸附模型和动力学模型拟合试验数据,通过测定复合体吸附铜离子前后的Zeta电位、扫描电子显微镜-能谱(SEM-EDS)和傅里叶红外光谱(FTIR),研究吸附剂对铜离子的吸附特性及机理。[结果]pH是影响吸附能力的主要因素,静电作用可使复合体表面负电荷增多,提高吸附量。在最适pH(5.0)下,复合体对铜离子的最大吸附量为13.08 mg/g。复合体对铜离子的吸附过程符合化学单分子吸附的Langmuir模型和二级动力学模型。[结论]该研究认为静电作用和单分子化学吸附是石英砂-腐殖酸-Cupriavidus gilardii CR3复合体吸附铜离子的主要机制。 相似文献
65.
V.A. Bampidis V. Christodoulou A. Chatzipanagiotou E. Sossidou A. Salangoudis 《Research in veterinary science》2010,88(3):456-457
This study aimed to evaluate effects of orally administered copper (Cu) to Chios sheep breed on serum levels of aspartate aminotransferase (AST), l-alanine aminotransferase (ALT), lactate deydrogenase (LDH) and alkaline phosphatase (ALP), in order to establish a practical and effective method in diagnosing the prehemolytic stage of chronic Cu poisoning. Eighteen ewes were allocated to three treatments of six ewes and fed a diet that contained 16.4 mg/day of Cu. Ewes in treatment Cu-0 received no additional Cu (control), while those in treatments Cu-60 and Cu-95 received 60 and 95 mg additional Cu/day, respectively, as an oral solution of copper sulfate. Therefore the ewes in treatment Cu-0, Cu-60 and Cu-95 consumed 16.4, 76.4 and 111.4 mg Cu/day, respectively. Serum enzyme levels were similar among treatments and all ewes remained clinically healthy until the end of the experiment. Results suggest that Chios ewes exhibit tolerance to Cu supplementation for up to 6 weeks. 相似文献
66.
《Communications in Soil Science and Plant Analysis》2012,43(14):1778-1790
Soil micronutrients were studied on loess soil with an 18-year long-term experiment. The results indicated that total soil iron and copper contents were similar under all treatments, but total soil manganese and zinc contents were significantly greater at the surface soil in the fertilized plots than in the controls, and total manganese contents were significantly greater in the whole soil profile under manure plus inorganic fertilizers than under controls. Generally, application of inorganic fertilizers had no effects on available soil micronutrient contents. The straw plus inorganic fertilizers significantly increased available manganese content at surface soil and available iron in subsurface soils. However, manure plus inorganic fertilizers significantly augmented soil-available iron contents throughout the profile, and raised available manganese, copper, and zinc contents, respectively, at surface soil relative to controls. The results suggest that long-term input of organic amendments alter the properties of soil and increase its plant-available micronutrient contents. 相似文献
67.
V. V. Agte M. K. Gokhale K. M. Paknikar S. A. Chiplonkar 《Plant foods for human nutrition (Dordrecht, Netherlands)》1995,48(2):149-158
Cereals including millets are consumed in India as a staple with wide variety of pulses and vegetables in varying proportions. Trace mineral contents of pearl millet are two to ten times higher than that of rice. Comparative performance of pearl millet based (PM) diets as against rice based (RB) diets in terms of trace mineral bioavailability was studied, based on the prevailing dietary patterns in India. In vitro percent dialysability of zinc, iron, copper and manganese under simulated gastrointestinal conditions was considered as indicator of metal bioavailability. Dialysable zinc and iron were estimated using 65 Zn and 59 Fe as tracers, while dialysable copper and manganese were measured by Atomic absorption spectrophotometer for 20 food items and 15 RB and 17 PM diets prepared from these items. Results indicated that percent dialysability of zinc and copper was higher for RB diets than PM diets, while that of iron and manganese were comparable. Total dialysable iron, copper and manganese in PM diet was 2 to 4 times higher than RB diet. 相似文献
68.
于2005年3~6月,以暴露方式,研究了铜(Cu2+)在河南华溪蟹(Sinopotamon honanense)肌肉和性腺中的积累与分布情况。4个Cu2+处理组浓度依次为5.12、16.18、51.13和161.56 mg/L。分别于处理后的24、721、20和168 h,取材、消化、测定Cu2+的含量。结果显示,铜在组织器官中的积累具有组织选择性。铜在肌肉中的积累趋势明显。同一时间,铜的积累随着浓度的升高而增加,具有明显的浓度-效应关系。同一浓度,铜的积累基本表现为随着时间的延长先升高后降低;铜在性腺中的积累趋势基本表现为随着暴露时间的延长呈现先升高后下降的趋势。 相似文献
69.
《Journal of plant nutrition》2013,36(12):2067-2083
Abstract Information is desired on plant species that have a great potential in phytoremediation of copper (Cu) contaminated soils. Two contrasting ecotypes of Elsholtzia argyi were comparatively studied using nutrient solution culture for their growth response and uptake, distribution, and translocation of Cu. The results show that the ecotype from an old mined area (Sanmen-ecotype) had greater tolerance to Cu than that from the nonmined area (Jiuxi-ecotype) based on dry matter yield at different Cu supply levels. Inhibited root and leaf growth was noted at the external Cu levels > 50 µmol L?1 for the Sanmen-ecotype, and at the Cu supply levels > 5 µmol L?1 for the Jiuxi-ecotype. Stem growth was most sensitive to Cu toxicity in E. argyi, and was inhibited at the Cu levels ≥ 2.5 µmol L?1 for Jiuxi-ecotype and ≥ 25 µmol L?1 for Sanmen-ecotype. Root Cu concentrations were higher in Sanmen-ecotype than in Jiuxi-ecotype, but leaf, especially stem Cu concentrations were much lower in the former than in the latter. Furthermore, Jiuxi-ecotype was much more efficient than Sanmen-ecotype in the translocation of Cu from root to the shoot, and it had higher ratios of stem/root and leaf/root Cu concentration. At the Cu supply levels higher than 10 µmol L?1, root concentrations of potassium (K), calcium (Ca), magnesium (Mg), manganese (Mn), and zinc (Zn) considerably decreased in Jiuxi-ecotype, but were not affected or even increased in Sanmen-ecotype. Zinc concentrations in the stems, particularly in the leaves of Sanmen-ecotype increased by 3 folds, but were hardly changed in Juixi-ecotype when grown at the Cu levels higher than 10 µmol L?1. These results indicate that the Sanmen-ecotype of E. argyi is a Cu-tolerant ecotype, and its tolerance to high Cu levels was mainly related to its extraordinary capability to restrict Cu uptake, especially Cu translocation from root to the shoot, probably by competitive uptake and translocation of Zn. 相似文献
70.