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1.
王荔娟 《闽西职业技术学院学报》2014,(4):113-116
测定了汀江某河段9个采样点表层沉积物重金属元素（As、Cr、Cd、Cu、Pb、Zn）的含量,并采用富集系数法、地累积指数法和潜在生态风险指数法对表层沉积物中重金属污染情况进行评价。研究结果表明,该河段表层沉积物受重金属污染已相当严重,其中以Cd污染最为严重,Cu、As次之,Cr、Pb、Zn污染较轻。总体上属于生态危害性很强的重污染水平。 相似文献
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Bo Sun Fen Zhang Guo-jun Zhou Guo-hai Chu Fang-fang Huang Qiao-mei Wang Li-feng Jin Fu-cheng Lin Jun Yang 《Journal of Zhejiang University. Science. B》2013,14(12):1100-1109
Alkaloids are plant secondary metabolites that are widely distributed in Nicotiana species and contribute greatly to the quality of tobacco leaves. Some alkaloids, such as nornicotine and myosmine, have adverse effects on human health. To reduce the content of harmful alkaloids in tobacco leaves through conventional breeding, a genetic study of the alkaloid variation among different genotypes is required. In this study, alkaloid profiles in leaves of five Nicotiana tabacum cultivars and Nicotiana tomentosiformis were investigated. Six alkaloids were identified from all six genotypes via gas chromatograph-mass spectrometry (GC-MS). Significant differences in alkaloid content were observed both among different leaf positions and among cultivars. The contents of nornicotine and myosmine were positively and significantly correlated (R 2=0.881), and were also separated from those of other alkaloids by clustering. Thus, the genotype plays a major role in alkaloid accumulation, indicating a high potential for manipulation of alkaloid content through traditional breeding. 相似文献
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以1年龄桐花树为材料,用完全营养液和不同浓度的煤矸石完全营养液浸出液进行栽培试验,对不同生长阶段的桐花树根形态指标及Cu、Zn、Mn含量进行测定和分析.结果表明:以5kg、10kg、20kg、30kg煤矸石粉分别加完全营养液配成30L培养液(分别标记为:A、B、C、D),其污染水平均超过国家I类水质的标准.其中Cu、Zn未超过II类水质标准,Mn超过II类水质标准.且煤矸石含量越高,污染也越严重.桐花树根部重金属含量的变化趋势是Mn含量较高,Zn含量次之,而Cu含量较低.且桐花树根部的Mn、Zn含量随着煤矸石浸出液浓度的增大而升高.桐花树根系在煤矸石浸出液中能够正常生长发育,表明其对煤矸石浸出液的耐性较强.试验表明桐花树对Mn、Zn是富集植物,可以考虑其作为净化污水的植物. 相似文献
4.
重金属铜锌对马尾松的外生菌根真菌的影响 总被引：2，自引：0，他引：2
刘晓蓉 《广东轻工职业技术学院学报》2003,2(1):10-13
选择马尾松的四种外生菌根真菌，分别用不同浓度的Cu^2＋和Zn^2＋处理，测定这四种菌的菌丝干重、培养9d后培养液中葡萄糖和氨氮的消耗量以及菌丝中Cu、Zn的含量，确定这四种菌对重金属的抵抗能力。结果表明：四种菌对重金属都有一定的抗性；低浓度的重金属不会抑制菌丝的生长，中等浓度对菌丝的生物量影响不明显，高浓度则明显地抑制菌丝的生长。 相似文献
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Wei-hong Sun Yong Wang Hua-gang He Xue Li Wan Song Bin Du Qing-wei Meng 《Journal of Zhejiang University. Science. B》2013,14(7):578-585
Ascorbate peroxidases are directly involved in reactive oxygen species (ROS) scavenging by reducing hydrogen peroxide to water. The tomato thylakoid-bound ascorbate peroxidase gene (StAPX) was introduced into tobacco. RNA gel blot analysis confirmed that StAPX in tomato leaves was induced by methylviologen-mediated oxidative stress. The sense transgenic seedlings exhibited higher tAPX activity than that of the wild type (WT) plants under oxidative stress conditions, while the antisense seedlings exhibited lower tAPX activity. Lower APX activities of antisense transgenic seedlings caused higher malondialdehyde contents and relative electrical conductivity. The sense transgenic seedlings with higher tAPX activity maintained higher chlorophyll content and showed the importance of tAPX in maintaining the optimal chloroplast development under methylviologen stress conditions, whereas the antisense lines maintained lower chlorophyll content than WT seedlings. Results indicated that the over-expression of StAPX enhanced tolerance to methylviologen-mediated oxidative stress in sense transgenic tobacco early seedlings, whereas the suppression of StAPX in antisense transgenic seedlings showed high sensitivity to oxidative stress. 相似文献
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Hai-qin Zhong Shun Zhang Hong Pan Ting Cai 《Journal of Zhejiang University. Science. B》2013,14(9):837-843
Objective
The efflux pump (EP) is one of the major mechanisms of antibiotic resistance in Klebsiella pneumoniae. However, there are few reports on the effect of the abuse of antibiotic use on the activity of EPs. To determine whether the use of low efficacy antibiotics has any effect on the activity of EPs and induces drug resistance in K. pneumoniae, we investigated the effect of ciprofloxacin on the activity of EPs in K. pneumoniae strains.Methods
Sixteen susceptible K. pneumoniae strains were isolated from patients and their minimum inhibitory concentrations (MICs) of ciprofloxacin were measured in the absence and presence of the pump inhibitor carbonyl cyanide m-chlorophenyl hydrazone (CCCP). The strains were then induced with a gradient of ciprofloxacin until the MICs of the strains showed no further increase, to obtain induced resistant strains. The EP activities of the strains before and after induction were compared using EP inhibition and ethidium bromide (EtBr) accumulation assays.Results
The MIC values of the strains were 16–256 times higher after induction than before induction. In the presence of CCCP, the MIC values of 50% of the induced strains were 2–4-fold lower than that in the absence of this inhibitor. The EtBr accumulation assay showed that the fluorescence of EtBr in the induced cells was lower than that in the cells before induction.Conclusions
EPs are widespread in susceptible and drug-resistant K. pneumoniae strains. Induction with ciprofloxacin may increase the activity of EPs in K. pneumoniae. The EtBr accumulation assay is more sensitive than the EP inhibition assay in evaluating the activity of EPs in K. pneumoniae. 相似文献10.
Ikram-ul- Haq Asif Ali Khan Iqrar Ahmad Khan Muhammad Abubakkar Azmat 《Journal of Zhejiang University. Science. B》2012,13(7):533-544
The okra germplasm was screened for salinity tolerance at the seedling stage and during plant ontogeny. Substantial variation existed in okra for salinity tolerance at the seedling stage. An 80 mmol/L NaCl concentration was suitable for discriminating tolerant and non-tolerant okra genotypes. The pooled ranking of the genotypes, based on individual rankings for each trait (root and shoot length, germination percentage, and relative Na+ and K+) in individual NaCl concentrations, was effective for selecting tolerant genotypes. Genotypes selected at the seedling stage maintained their tolerance to NaCl during plant ontogeny, suggesting that screening of the germplasm entries and advanced breeding materials for salt tolerance at the seedling stage is effective. Among 39 okra genotypes, five were identified as the most tolerant genotypes and showed potential for use in breeding programs that focus on the development of salt-tolerant, high-yield okra cultivars. 相似文献
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苏州河底泥重金属形态分析 总被引：2，自引：0，他引：2
Nine elements （As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn） in sediment samples at 7 sites （Site 1-7） from Suzhou Creek in Shanghai were analyzed with the Community Bareau of Reference （BCR） （sequential extraction （SE）） protocol and simultaneously extracted metals （SEM）/acid volatile sulfide （AVS） procedure to assess the metal bioavailability and toxicology in this area. The results showed that the BCR extraction can be utilized as an additional tool with the AVS method for assessing the potential bioavailability and toxicity of metals in sediments. Pollution from S5 （Site 5） was more severe than from other sites, especially Pb, Cu and Zn. Among all the sites, more than 80% of the total concentration of Fe existed in the residual fraction, As, Cr, Mn also dominated in the residual fraction （more than 50%）. While Cd, Ni and Zn （more than 35%） were mainly in the non-stable phase. Cu had a strong affinity with oxidizable phase and Pb varied from site to site. The SEM/AVS ratio was less than one in these sediments and results implied that the majority of Zn and Ni （〉 40%） were bound to AVS. In contrast, Pb, Cu and Cd were little bound to AVS due to their low ration of SEM-Pb, Cu, Cd to corresponding total concentration and relatively high Dorewater concentration. 相似文献
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Transgenic Brassica compestris L.spp.chinensis plants expressing a choline oxidase(codA) gene from Arthrobacter globiformis were obtained through Agrobacterium tumefaciens-mediated transformation.In the transgenic plants,codA gene expression and its product transportation to chloroplasts were detected by the enzyme-linked immunosorbent assay(ELISA) examination,immunogold localization,and 1 H-nuclear magnetic resonance( 1 H-NMR) . Stress tolerance was evaluated in the T3 plants under extreme temperature and salinity conditions.The plants of transgenic line 1(L1) showed significantly higher net photosynthetic rate(Pn) and Pn recovery rate under high(45°C,4 h) and low temperature(1°C,48 h) treatments,and higher photosynthetic rate under high salinity conditions(100,200,and 300 mmol/L NaCl,respectively) than the wild-type plants.The enhanced tolerance to high temperature and high salinity stresses in transgenic plants is associated with the accumulation of betaine,which is not found in the wild-type plants.Our results indicate that the introduction of codA gene from Arthrobacter globiformis into Brassica compestris L.spp.chinensis could be a potential strategy for improving the plant tolerance to multiple stresses. 相似文献
14.
Qi-chao ZHAO Ming-hong LIU Xian-wen ZHANG Chao-yang LIN Qing ZHANG Zhi-cheng SHEN 《Journal of Zhejiang University. Science. B》2015,16(10):824-831
Insect resistance and glyphosate tolerance have been two of the most important traits in the genetic improvement of various crops. In this study, two Bacillus thuringiensis (Bt) insecticidal genes, Cry1Ac and Cry1Ig, and a modified glyphosate-tolerant 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) gene (G10) were combined into a single transferred DNA (T-DNA) fragment and introduced into rice by Agrobacterium-mediated transformation. A transgenic line with single-copy T-DNA insertion named GAI-14 was found to be highly resistant to striped stem borer and rice leaf roller, and tolerant to glyphosate. Analysis of T-DNA border sequence suggested that the transgenes were inserted at the chromosome 3 and appeared to have not interrupted any known or putative genes. A field trial observed no significant difference in the basic agronomic traits between GAI-14 and the recipient rice. 相似文献
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对 ６５例糖尿病患者进行了血清中微量元素锌、铜、铁、铬、锰的含量测定,并与正常对照组进行了比较．结果表明,病例组的糖尿病患者血清锌、铁、铬、锰均低于对照组,其中锌、铬、锰水平与对照组比较差异显著（Ｐ＜０．０５）;血清铁虽低于对照组,但无统计学意义．血清钢水平则高于对照组,铜水平与对照组比较差异显著（Ｐ＜０．０５）． 相似文献
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通过湖南花垣和苏仙两矿区野外踏查,数据检测Pb、Zn、Cu、Cd在两矿区相应植物土壤及植物中的含量及相关分析。结果表明：两矿区均受到Pb、Zn、Cd的污染。Pb元素在苏仙矿区是重污染,Zn对花垣矿区为中度污染,Cd对两矿区污染均为重污染,综合污染指数表明两矿区均为重污染。通过富集系数、转移系数、滞留率分析,发现14种优势植物表现出不同的吸收和富集特征,其中箬竹(Indocalamus tessella?tus)、油茶(Camellia oleifera)为富集型植物,菖蒲(Acorus calamus)、灯心草(Juncus effusus)、节节草(Equisetum ramosissimum)、毛萼莓(Rubus chroosepalus)、茅草(Imperata cylindrica)为根部囤积型植物,飞龙掌血(Todda?lia asiatica)为规避型植物。 相似文献
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沱江内江段鲫鱼和鲤鱼体内重金属分布规律 总被引：1，自引：0，他引：1
摘要：从沱江内江市城区段中采集的鲫鱼、鲤鱼,测定其鳃、鳞、骨、卵巢、肾、鳔和肌肉等器官中的Cu,Zn,Pb和Cd的含量．结果表明：重金属Cu在鲫鱼体内的累积为卵巢〉骨〉鳃〉肾〉鳞〉鳔〉肌肉,在鲤鱼体内累积为卵巢〉骨〉鳞〉肾〉鳃〉鳔〉肌肉;重金属Zn在鲫鱼体内累积为鳃〉骨〉鳞〉卵巢〉鳔〉肾〉肌肉,在鲤鱼体内累积为鳃〉骨〉鳔〉卵巢〉鳞〉肾〉肌肉;Zn在鲫鱼和鲤鱼体内各组织和器官含量较多;Cu在骨中含量较高．Pb和Cd在鲫鱼和鲤鱼体内分布为骨〉鳞〉鳃〉肾〉肌肉〉鳔〉卵巢． 相似文献
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用原子吸收光谱法对银杏叶中十三种矿物元素进行了分析测定,结果显示,本方法精密度和回收率较好.在选定的实验条件下,银杏叶中各元素间相互不干扰,可在一份样品液中进行13种元素的分别测定;所测银杏叶中含有丰富的Ca、K、Mg、Fe、Mn、Zn以及Cu、Ni,有毒金属Pb、Cd被检出,加标回收率在86.03%-113.81%之间,RSD≤3.6(n=6). 相似文献
19.
Interaction of salinity and cadmium stresses on mineral nutrients,sodium, and cadmium accumulation in four barley genotypes 总被引：1，自引：0，他引：1
Interaction of salinity （NaCI） and cadmium （Cd） on growth, mineral nutrients, Na and Cd accumulation in four barley genotypes differing in salt tolerance was studied in a hydroponic experiment. Cd, NaCI and their combined stresses reduced Ca and Mg concentrations in roots and shoots, K concentration in shoots, increased K and Cu concentrations in roots relative to control, but had non-significant effect on micronutrients Cu, Fe and Mn concentrations in shoot. The three stresses reduced accumulation of most tested nutrients in both roots and shoots, except NaCI and NaCl＋Cd stresses for root K and shoot Cu accumulation in salt tolerant genotypes. The salt tolerant genotypes did not have higher nutrient concentration and accumulation than the sensitive ones when exposed to Cd and NaCI stresses. In conclusion, the affecting mechanism of Cd stress on nutrients was to some extent different from salinity stress, and the NaCl＋Cd stress was not equal to additional Cd and NaCI stresses, probably due to the different valence and competitive site of Na^＋ and Cd^2＋. NaCI addition in the Cd-containing medium caused remarkable reductions in both Cd concentration and accumulation, with the extent of reduction being also dependent on genotypes. The salt-tolerant genotypes had lower Na concentration than sensitive ones. 相似文献
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Chun-lei Yang Le-luo Guan Jian-xin Liu Jia-kun Wang 《Journal of Zhejiang University. Science. B》2015,16(8):709-719
The presence of yeast cells could stimulate hydrogen utilization of acetogens and enhance acetogenesis. To understand the roles of acetogens in rumen fermentation, an in vitro rumen fermentation experiment was conducted with addition of acetogen strain (TWA4) and/or Saccharomyces cerevisiae fermentation product (XP). A 2×2 factorial design with two levels of TWA4 (0 or 2×107 cells/ml) and XP (0 or 2 g/L) was performed. Volatile fatty acids (VFAs) were increased (P<0.05) in XP and TWA4XP, while methane was increased only in TWA4XP (P<0.05). The increase rate of microorganisms with formyltetrahydrofolate synthetase, especially acetogens, was higher than that of methanogens under all treatments. Lachnospiraceae was predominant in all acetogen communities, but without close acetyl-CoA synthase (ACS) amino acid sequences from cultured isolates. Low-Acetitomaculum ruminis-like ACS was predominant in all acetogen communities, while four unique phylotypes in XP treatment were all amino acid identified low-Eubacterium limosum-like acetogens. It differs to XP treatment that more low-A. ruminis-like and less low-E. limosum-like sequences were identified in TWA4 and TWA4XP treatments. Enhancing acetogenesis by supplementation with an acetogen strain and/or yeast cells may be an approach to mitigate methane, by targeting proper acetogens such as uncultured low-E. limosum-like acetogens. 相似文献