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1.
目的:建立电感耦合等离子体原子发射光谱法(ICP-AES)测定太子参及其种植土壤中16种元素含量的方法.方法:采用微波消解处理样品,并考察了不同元素间相互干扰,采用ICP-AES同时测定16种元素.结果:对所测定元素的相时标准偏差(RSD)均小于4%,回收率在95%~104%之间,结果可信度高.结论:本研究所建立的方法具有简便、快速、准确、灵敏度高的优点.  相似文献   

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建立了电感耦合等离子体质谱法(ICP-MS)测定茵栀黄注射液中Pb、As、Cd、Hg、Cu 5种元素的方法。样品经微波消解后,直接用ICP-MS同时测定上述5种元素,结果5种元素的检出限分别在5~1250 ng/L之间;线性良好,线性相关系数均为r≥0.999;精密度RSD3.5%;回收率在95.7%~107.5%之间。方法操作简便、分析速度快、灵敏度高,各项分析性能指标均达到要求,适用于茵栀黄注射液中有害元素的测定。  相似文献   

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目的:采用微波消解—电感耦合等离子质谱法(ICP-MS)分别对液体水基、固体颗粒基、固体片剂和软胶囊4种不同基质的保健品中的钾、钙、钠、镁、铁、锰、铜、锌、铅、砷进行同时分析测定。方法:样品经过微波消解后,使用电感耦合等离子质谱仪分别对4种基质的10种元素进行同时测定。结果:经测定,该方法的线性范围宽,线性良好,线性相关系数均在0.999以上;灵敏度高,各元素的检出限在0.008~3.9mg/kg之间;10种元素的回收率在85.0%~109%之间,精密度在1.2%~9.7%之间。结论:本方法能方便、准确、灵敏的对液体水基、固体颗粒基、固体片剂和软胶囊4种不同基质的保健品种10种元素进行同时测定。  相似文献   

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目的:建立海南产冰糖草中重金属元素含量测定方法,测定其重金属元素含量。方法:采用氢化物原子荧光法建立冰糖草中重金属砷、汞、铅、镉元素的分析检测方法。结果:4种重金属元素的线性相关系数为0.9991-0.9999,精密度小于2.74%,加标回收率为95%~102.3%,RSD≤3.36%。冰糖草中重金属元素含量均符合绿色中药标准。结论:该方法简便、准确、稳定,可用于冰糖草的质量控制。  相似文献   

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二道坊河沉积物中重金属等元素富集特征的研究   总被引:5,自引:1,他引:4  
以二道坊河沉积物为研究对象 ,采用相关与回归分析综合地研究了 1 4种元素在沉积物中的富集特征 .结果表明 :地球化学性质相近的元素 ,它们在沉积物中的相关系数大多达到了显著或极显著的水平 ;通过因子分析 ,求出了 4个主因子 ,它们代表沉积物中1 4种元素测定信息的 85% ,以第一、二主因子对应的特征向量为X、Y轴将 1 4个元素分成了 3类 ;建立了大部分元素与沉积物性质之间的多元回归方程 .  相似文献   

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福建省耕地土壤重金属含量和可浸提性研究   总被引:11,自引:3,他引:8  
测定了福建省6市、县耕地土壤中的Cu、Zn、Cd、Ni、Pb、Hg、As等7种重金属元素的全量和可浸提态含量,并对测定结果进行了数理统计。结果表明,福建省耕地土壤存在着不同程度的重金属污染,但依元素不同而不同,重金属可浸提态含量占全量的10.0?52.2 Cu、Zn、Cd、Pb、Ni的可浸提态含量与全量之间的相关达极显著水平,Zn、Cd、Pb、As等4元素含量之间存在着显著正相关,而Ni则只与Zn元素有极显著正相关,Cu和Hg与其它重金属元素的相关则均不显著。  相似文献   

7.
采用微波消解,建立了电感耦合等离子体质谱法(ICP-MS)同时测定干紫菜中28种元素的检测方法。结果显示:在0.05~100.0μg/L浓度范围内,28种元素标准曲线线性关系良好,相关系数(r2)≥0.9998;检出限在0.05~0.50μg/L之间,加标回收率在92.8%~102.6%之间,相对标准偏差(RSD)在0.8%~2.7%之间;根据干紫菜中元素含量测定结果,干紫菜富含对人体有益的I、K、Na、P、Ca、Mg、Fe元素,尤其是I含量高达18 695mg/kg,而对人体危害有害的重金属元素As、Ag、Cd、Hg、Pb含量较低。通过对干紫菜中元素含量测定,可为干紫菜质量检测、质量评价及其产业可持续发展提供科学依据。  相似文献   

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本文采用ICP-OES法,测定分析了长梗喉毛花和镰萼喉毛花中的21种矿质元素。所采用方法线性关系良好,r≥0.9990,各元素的检出限均低于0.0036 mg/L,建立了测定喉毛花中多种矿质元素含量的分析方法。结果表明,两种喉毛花中Ca、Mg、Fe三种元素的含量均较高。在检出的人体所需常量和微量元素中,除Se元素外,其他常量、微量元素在长梗喉毛花中含量均高于在镰萼喉毛花中的含量。Pb、As两种重金属元素在镰萼喉毛花中的均含量高于在长梗喉毛花中的含量,Cu则反之。  相似文献   

9.
ICP-OES法测定两种喉毛花植物中21种矿质元素   总被引:1,自引:0,他引:1  
本文采用ICP-OES法,测定分析了长梗喉毛花和镰萼喉毛花中的21种矿质元素。所采用方法线性关系良好,r≥0.9990,各元素的检出限均低于0.0036 mg/L,建立了测定喉毛花中多种矿质元素含量的分析方法。结果表明,两种喉毛花中Ca、Mg、Fe三种元素的含量均较高。在检出的人体所需常量和微量元素中,除Se元素外,其他常量、微量元素在长梗喉毛花中含量均高于在镰萼喉毛花中的含量。Pb、As两种重金属元素在镰萼喉毛花中的均含量高于在长梗喉毛花中的含量,Cu则反之。  相似文献   

10.
目的:建立锁阳中19种无机元素含量的近红外光谱(NIR)快速测定模型,筛选适宜采用NIR技术进行测定的元素。方法:采集5个省(区)的82批锁阳样品,采用积分球漫反射方式采集样品的NIR原始光谱,采用电感耦合等离子体-质谱(ICP-MS)法测定Na、K、Ca、Mg、Fe、Zn、Mn、Co、Sr、Ni、Ag、Ba、Ti、Pb、Cr、Cd、As、Hg、Cu等19种无机元素含量的化学参考值,筛选预处理原始光谱的化学计量学方法,筛选最佳波段及因子数,以偏最小二乘法(PLS)建立NIR定量分析模型。结果:K、Ca、Mg、Mn、Co、Sr、Ti、Cr元素的决定系数R2及交叉验证R2均大于0.9,校正均方差(RMSEC)、预测均方差(RMSEP)及留一法交叉验证均方差(RMSECV)在0.52~2.20之间,模型预测值与真实值之间具有较好的相关性,预测性能较好;Ni、Zn元素的决定系数R2及交叉验证R2在0.8~0.9之间,RMSEC、RMSEP及RMSECV在0.49~1.41之间,预测值与真实值之间的相关性一般;Cu元素的决定系数R2及交叉验证R2在0.7~0.8之间,Na、Fe、Ag、Ba、Pb...  相似文献   

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It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.  相似文献   

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Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.  相似文献   

18.
Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.  相似文献   

19.
肝癌中HBV和HCV基因和抗原的分布及意义   总被引:1,自引:0,他引:1  
采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细  相似文献   

20.
For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.  相似文献   

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