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121.
The sarcophagus containing the remains of Federico II, located in the Cathedral of Palermo (Sicily, Italy), was opened on 1998 to perform a multidisciplinary survey [1]. Next to the remains of Federico II and in close contact with them were laying two other skeletons belonging, according to historical records, to Pietro II di Aragona and to an anonymous person (“The Third Individual”), probably a woman. The bones appeared severely deteriorated. Chemical analysis performed on bone samples excluded that the bodies underwent some kind of embalming process. The analysis of mtDNA from bone samples taken from the three skeletons was successful in only one of the two labs involved. The HVR1-mtDNA sequence (region: from nt 16,035 to nt 16,395), obtained from the bone samples of Federico II and “The Third Individual” appear identical but bear double peaks at the same nucleotide positions, suggesting mixing (i.e. contamination) of different mtDNA types. The HVR1 sequence obtained from the bone sample of Pietro II di Aragona does not present double peaks and differ from the Cambridge Reference Sequence (CRS) at six nucleotide positions. Cloning experiment of the Federico II amplicon demonstrated that the mixed mtDNA types are only two: one identical to CRS, the other identical to the sequence of Pietro II di Aragona. A reconstruction of these data are proposed in the Discussion. Due to the problematic context in which this study was carried out (mixed and deteriorated biological material, failure to replicate results in two different labs), our results and reconstruction can only be offered on a tentative basis. It is hoped that the data presented in this study will reveal useful, for future comparison, if further molecular genetics research will be carried out on the royal dynasties that ruled Sicily in the early centuries of the past millennium.  相似文献   
122.
研究目的:二氧化钛(TiO2)纳米颗粒已经广泛应用于化妆品、防晒霜、涂料和牙膏等。这些纳米颗粒性质非常稳定,能在废水和生物固体中转移和分散。现有研究表明,TiO2纳米颗粒对动物正常生理活动具有毒性等负面作用。但是,它们对植物是否具有毒性特别是是否会产生植物基因毒性至今尚不清楚。因此,本文使用随机扩增多态性DNA技术研究TiO2纳米颗粒是否对西葫芦具有基因毒性,为TiO2纳米颗粒排放进入环境后的潜在植物毒性风险评价提供依据。 创新要点:首次发现了TiO2纳米颗粒对西葫芦具有基因毒性。 重要结论:采用随机扩增多态性DNA技术,发现TiO2纳米颗粒污染处理的西葫芦样品与未处理样品的基因组DNA图谱相比,不仅在谱带强度有明显差异,而且存在谱带消失和新谱带产生现象,表明TiO2纳米颗粒对西葫芦具有基因毒性。  相似文献   
123.
用紫外光谱法和黏度法研究2-羟甲基苯并咪唑与DNA的相互作用,考察离子强度对两者相互作用的影响。结果表明:在pH=7.40的Tris-HCl缓冲溶液中,DNA使2-羟甲基苯并咪唑的紫外吸收光谱减色且红移,测得2-羟甲基苯并咪唑与DNA的结合常数为5.2×107 L?mol-1。随2-羟甲基苯并咪唑浓度增大,DNA黏度增大,NaCl浓度增加,DNA-2-羟甲基苯并咪唑体系吸光度无明显变化,2-羟甲基苯并咪唑以嵌插作用方式与DNA结合。  相似文献   
124.
INTRODUCTION Genetic diversity is a major issue of conserva-tion biology recognized by the IUCN (Frankham etal., 2002). Within a population it reflects the evolu-tionary potential to adapt to novel environmentalchanges. Therefore, during the past few years, thegenetic diversity of many threatened mammals, birds,fish, insects and plants have been investigated(Frankham et al., 2002). As a direct and indirectconsequence of human actions, more and more spe-cies or populations are faci…  相似文献   
125.
对与PCR实验紧密相关的计算机软件——引物设计软件、凝胶图像处理软件、数据分析软件和文献查找软件的应用进行了概述。  相似文献   
126.
线粒体DNA具有突变速度快、重组率低、严格母系遗传、拷贝数多等特点,近年来成为分子考古研究中的一个热点。为了研究古墓群中的血亲关系,可以从古墓葬遗留骨骸、牙齿中提取和扩增mtDNA片断进行分析。通过设计2对部分重叠的引物,扩增线粒体16055-16218区域目标片段,进行反相高效液相色谱分析,确认四个样品对应片断在反相柱上的保留时间上存在差异,以此推断扩增片段在序列上可能存在差异。为利用mtDNA分析人类母系血缘关系奠定了基础。  相似文献   
127.
导出了普适性的DNA介导的限制性发光猝灭方程:I0/I=a/[1+exp(b-KLQQ)].提出了表观猝灭常数KLQ,最大猝灭量a和半猝灭量Q1/2等概念.将高度智能化的演化计算技术引入了配合物与DNA作用的研究中,并用LQ方程对5个发光猝灭体系进行了演化优化.计算结果十分理想  相似文献   
128.
DNA分类方法的探讨   总被引:3,自引:0,他引:3  
DNA序列分类的方法有很多种.本文给出了两种模型都是在图象的基础上,利用图象的直观、易于分析等优点,找到各种碱基不同的特征,得出一个比较合理的方法. 在建立模型时,先计算出给定的前20种DNA序列中各碱基A,G、C、T的含量 (将一串长序列简化成了四个百分含量数值,大大简化了序列),并以此含量为数据作出直角坐标系下的二维曲线.根据曲线的特征,得出了两个算法,一个是以其中的一个DNA序列中碱基的含量大于其它三种含量为特征分出类别,对21至40种序列的分类正确率达到 80%,对于题中所给的 182种序列分类正确率为 42%;另一个是通过转化曲线为直线的方法找出符合分类特征的区间,根据是否在此区间内而分出类别,对21至40种序列的分类正确率达到100%,对于题中所给的182种序列分类正确率为85%. 最后,通过对比两种模型的结果,判断出两种模型的优劣,并分析了其中的原因.  相似文献   
129.
Objective: To investigate molecular alterations associating with prostate carcinoma progression and potentially provide information toward more accurate prognosis/diagnosis. Methods: A set of laser captured microdissected (LCM) specimens from 300 prostate cancer (PCa) patients undergoing radical prostatectomy (RP) were defined. Ten patients representing "aggressive" PCa, and 10 representing "non-aggressive" PCa were selected based on prostate-specific antigen (PSA) recurrence,Gleason score, pathological stage and tumor cell differentiation, with matched patient age and race between the two groups.Normal and neoplastic prostate epithelial cells were collected with LCM from frozen tissue slides obtained from the RP specimens.The expressions of a panel of genes, including NPY, PTEN, AR,AMACR, DD3, and GSTP1, were measured by quantitative real-time RT-PCR (TaqMan), and correlation was analyzed with clinicopathological features. Results: The expressions of AMACR and DD3 were consistently up-regulated in cancer cells compared to benign prostate epithelial cells in all PCa patients, whereas GSTP1 expression was down regulated in each patient. NPY, PTEN and AR exhibited a striking difference in their expression patterns between aggressive and non-aggressive PCas (P=0.0203, 0.0284, and 0.0378, respectively, Wilcoxon rank sum test). The lower expression of NPY showed association with "aggressive" PCas based on a larger PCa patient cohort analysis (P=0.0037,univariate generalized linear model (GLM) analysis). Conclusion: Despite widely noted heterogeneous nature of PCa, gene expression alterations of AMACR, DD3, and GSTP1 in LCM-derived PCa epithelial cells suggest for common underlying mechanisms in the initiation of PCa. Lower NPY expression level is significantly associated with more aggressive clinical behavior of PCa; PTEN and AR may have potential in defining PCa with aggressive clinical behavior. Studies along these lines have potential to define PCa-associated gene expression alterations and likely co-regulation of genes/pathways critical in the biology of PCa onset/progression.  相似文献   
130.
The primary theme of this paper is the normative case against ownership of one's genetic information along with the source of that information (usually human tissues samples). The argument presented here against such "upstream" property rights is based primarily on utilitarian grounds. This issue has new salience thanks to the Human Genome Project and "bio-prospecting" initiatives based on the aggregation of genetic information, such as the one being managed by deCODE Genetics in Iceland. The rationale for ownership is twofold: ownership will protect the basic human rights of privacy and autonomy and it will enable the data subjects to share in the tangible benefits of the genetic research. Proponents of this viewpoint often cite the principle of genetic exceptionalism, which asserts that genetic information needs a higher level of protection than other kinds of personal information such as financial data. We argue, however, that the recognition of such ownership rights would lead to inefficiency along with the disutility of genetic discoveries. Biomedical research will be hampered if property rights in genes and genetic material are too extensive. We contend that other mechanisms such as informed consent and strict confidentiality rules can accomplish the same result as a property right without the liabilities of an exclusive entitlement.  相似文献   
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