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61.
A solution with different Cu supply levels was cultured to investigate gama-aminobutyric acid (GABA) accumulation in Elsholtzia splendens, a native Chinese Cu-tolerant and accumulating plant species. Increasing Cu from 0.25 to 500 μmol/L significantly enhanced levels of GABA and histidine (His), but  相似文献   
62.
本文重点介绍运用Socket端口扫描技术,判断端口是否打开;接着关联端口和进程名,找到打开端口的进程名,并依据木马的一些基本特征检测出系统中的木马。而系统中的端口数量巨大,为了提高扫描速度节约时间,采用VC^ 的多线程,把多线程和端口扫描融合在一起,进行多线程端口扫描。实验表明,本系统在扫描速度方面有较优。越的性能。  相似文献   
63.
A solution with different Cu supply levels was cultured to investigate gama-aminobutyric acid (GABA) accumulation in Elsholtzia splendens, a native Chinese Cu-tolerant and accumulating plant species. Increasing Cu from 0.25 to 500 μmol/L significantly enhanced levels of GABA and histidine (His), but considerably decreased levels of aspartate (Asp) and glutamate (Glu) in the leaves. The leaf Asp level negatively correlated with leaf Cu level, while leaf GABA level positively correlated with leaf Cu level. The leaf Glu level negatively correlated with leaf GABA level in Elsholtzia splendens. The depletion of leaf Glu may be related to the enhanced synthesis of leaf GABA under Cu stress.  相似文献   
64.
用HNO3溶解试样,在几个相同量的试液中,分别加入浓度依次递增的5 种元素的标准溶液,用空气-乙炔火焰原子吸收法连续测定Cu,Ca,Fe,Mn和Ni的含量,建立了优化的仪器测定条件,并对可能存在的元素进行了干扰实验,方法的回收率为98.4%-102.5%,相对标准偏差为1.9%-3.0%。  相似文献   
65.
Alzheimer’s disease is the most common form of dementia in the elderly and it’s prevalence is rapidly rising. Oxidative stress plays important role in the pathophysiology of Alzheimer’s disease. Metals like copper, iron derived through diet can act as pro-oxidant under oxidative stress. In the present study, serum copper levels were evaluated in 50 patients with Alzheimer’s disease, 24 patients with Vascular Dementia and 30 controls. All the groups were also investigated for serum ceruloplsmin levels. The mean copper levels in Alzheimer’s disease and Vascular Dementia were significantly raised compared to controls. An attempt has been made to study the relationship of serum copper with ceruloplasmin. Our study found weak correlation between copper and ceruloplasmin levels in Alzheimer’s disease and Vascular Dementia.  相似文献   
66.
用过渡金属铜为配位中心,以5-氨基-1,10-菲咯啉对羟基苯甲醛西佛碱铜配合物为配体,合成了一种新的、可作为核酸荧光探针的金属配合物,并对其与DNA的作用作了初步的研究。  相似文献   
67.
利用2-吡啶甲醛、N,N-二甲基乙二胺制备了一种新的席夫碱铜配合物,并通过X-射线单晶衍射、元素分析和ESI-MS对其结构进行分析.晶体结构分析表明,配合物呈现扭曲的四方锥构型.用紫外-可见吸收光谱、荧光光谱和圆二色光谱研究了配合物与小牛胸腺DNA(CT-DNA)和人血清白蛋白(HSA)的结合性质.结果表明:配合物以插入的方式与DNA相互作用,且配合物与HSA的相互作用为静态猝灭机制,分子间作用力为氢键和范德华力.  相似文献   
68.
本文以铁琴铜剑楼藏元刊本《资治通鉴》近10万字长跋为例,揭示明末清初苏州地区文、严两家以严虞悖为代表的士人之阅读轨迹、遗闻轶事,以裨知人论世之资,籍此进一步管窥清代藏书题跋蕴含的丰富文献、史料、文化价值。  相似文献   
69.
某铜镍矿对铜镍分离进行选矿试验研究,论证了铜镍混合精矿进行分离的可行性,以及铜镍分离产生铜、镍单一精矿后的新增效益要高于铜镍混合精矿的经济效益。  相似文献   
70.
The efficiency of chlorine and chloramines disinfection on biofilm development in a simulated drinking water distribution system was investigated by using heterotrophic bacterial spread plate technique. The experiments were carried out with four annular reactors (ARs) with stainless steel (SS) or copper (Cu) material slides. The results showed that there were fewer bacteria attached to Cu slides without a disinfectant compared with those attached to SS slides. When the water was disinfected with chloramines, the heterotrophic plate counts (HPCs) on the biofilm attached to the Cu slides were significantly lower (by 3.46 log CFU/cm^2) than those attached to the SS slides. Likewise, the biofilm HPC numbers on the Cu slides were slightly lower (by 1.19 log CFU/cm^2) than those on the SS slides disinfected with chlorine. In a quasi-steady state, the HPC levels on Cu slides can be reduced to 3.0 log CFU/cm^2 with chlorine and to about 0.9 log CFU/cm^2 with chloramines. The addition of chloramines resulted in a more efficient reduction of biofilm heterotrophic bacteria than did chlorine. We concluded that the chlorine and chloramines levels usually employed in water distribution system were not sufficient to prevent the growth and development of microbial biofilm. The combination of copper pipe slides and chloramines as the disinfectant was the most efficient combination to bring about diminished bacterial levels.  相似文献   
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