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81.
基于XML技术的电子病历管理平台研究与实现   总被引:3,自引:0,他引:3  
介绍电子病历的内涵与发展历程,阐述基于XML技术电子病历管理平台构建的意义、功能及实现方案,从基于XML的电子病历建模,支持HL7、DICOM和XML集成医疗网关,基于SOA、多标准兼容集成网关的系统架构几方面介绍平台的具体实现技术。  相似文献   
82.
This study provided an experimental evidence for the use of cyclen (1, 4, 7, 10‐tetraazacyclododecane)‐based polymer for gene delivery. The interesting interaction of the polymer with plasmid DNA was studied by using fluorescence titration, circular dichroism spectra, agarose gel electrophoresis and atomic force microscopy. It was found that polyplex was formed between the polycation and plasmid DNA. The results demonstrated that the cyclen‐based polymer could act as non‐viral gene vector with relatively low cytotoxicity.  相似文献   
83.
基于四阶累积量矩阵子空间分解的脑电逆问题算法   总被引:2,自引:1,他引:1  
根据头表观测电位反演脑电源的空间位置是脑电研究中的一个重要问题,基于四阶累积量矩阵的子空间分解,提出了一种新的脑电问题算法,与现有的基于二阶统计量矩阵的子空间分解算法相比,二阶方法存在对空间相关噪音敏感的问题,而阶方法可以抑制在时间方向上呈高斯分析,在空间方向相关的噪音,从而显示了四阶方法的较好性能。  相似文献   
84.
在脑电头皮电位的测量技术中,零参考点的选取一直是一个争论的焦点,研究人员都希望找到一个可行的通用参考零点,以方便研究成果间的比较和借鉴。针对脑电头皮电位质心的计算问题,用仿真和实际数据计算比较了平均参考、连接耳参考、头顶参考和新近出现的近似零参考技术(REST)方法的差异,结果表明,采用REST可使得电位质心的计算误差在多数情况下更小。说明在进行质心等与脑电波形相关的计算时,采用近似的REST可以获得更为真实的计算结果。  相似文献   
85.
医疗数据整合模式的研究   总被引:2,自引:0,他引:2  
HL7是涉及到许多不同领域的医疗数据交换标准。通过对该标准的分析,本研究从最底层的结构入手,提出一种进行HL7完整构造的通用方法,并通过软件算法完全实现了此方法。本方法将XML对象树与数据表结合;它不同于其它文献所提的只针对HL7某一特定点或层次的方法,它不仅包含HL7的横向全部消息也深入了HL7的纵向所有层次。另外在此基础上,还提出了一个包含HL7适配器和HL7网关的,适合于不同医疗系统的信息整合模型。  相似文献   
86.
To explore the clinical implication of activin receptor-like kinase 7 (ALK7) expression in breast cancer, we evaluated its protein level in six kinds of human breast tissue samples, including adjacent normal tissues, adenosis, breast fibroadenoma, ductal carcinoma in situ (DCIS), invasive ductal carcinoma (IDC), and lymph node metastases (LNM). Immunohistochemical analyses showed that ALK7 was more frequently and much more intensely expressed in adjacent normal tissues, adenosis, and fibroadenoma tissues than in malignant tissues (DCIS, IDC, and LNM). Furthermore, the ALK7 expression in primary tumors and the corresponding LNM was evaluated in parallel samples from 60 patients with IDC. Results showed that the ALK7 expression status in primary tumors and LNM was concordant in 53 patients (88%), suggesting that ALK7 expression was retained in LNM. Moreover, our results suggested that ALK7 expression inversely correlated with the tumor grade (P?=?0.009) and clinical stage (P?=?0.004) in IDC significantly. Finally, the effect of activin-ALK7 pathway on the breast cancer cell growth was elucidated, and results revealed that overexpression of ALK7 could restore the inhibitory effect of activin B on the growth of ALK7-negative breast cancer cell line, ZR-75-30. These findings provide the evidence that the reduction or lack of ALK7 expression may account for the loss of its ligand sensitivity of breast cancer cells, thereby leading to breast tumor progression.  相似文献   
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Plant and animal centromeres comprise megabases of highly repeated satellite sequences, yet centromere function can be specified epigenetically on single-copy DNA by the presence of nucleosomes containing a centromere-specific variant of histone H3 (cenH3). We determined the positions of cenH3 nucleosomes in rice (Oryza sativa), which has centromeres composed of both the 155-bp CentO satellite repeat and single-copy non-CentO sequences. We find that cenH3 nucleosomes protect 90–100 bp of DNA from micrococcal nuclease digestion, sufficient for only a single wrap of DNA around the cenH3 nucleosome core. cenH3 nucleosomes are translationally phased with 155-bp periodicity on CentO repeats, but not on non-CentO sequences. CentO repeats have an ∼10-bp periodicity in WW dinucleotides and in micrococcal nuclease cleavage, providing evidence for rotational phasing of cenH3 nucleosomes on CentO and suggesting that satellites evolve for translational and rotational stabilization of centromeric nucleosomes.Centromeres, the chromosomal domains that attach to spindle microtubules to segregate eukaryotic chromosomes in mitosis and meiosis, are DNA elements bound by special nucleosomes that contain a centromere-specific variant of histone H3 (cenH3). In most plants and animals, cenH3 nucleosomes are found on centromeric DNA that comprises megabases of tandemly repeated “satellite” sequences. Despite this apparent preference for repetitive DNA, a fully functional centromere, called a neocentromere, can occasionally form by assembling cenH3 nucleosomes on a single-copy DNA sequence that was not previously part of a centromere, indicating that centromere specification is epigenetic in plants and animals (for reviews, see refs. 14).The tandem arrays of highly repeated satellite sequences that compose most plant and animal centromeres can differ dramatically between closely related species (5), and even between different chromosomes (68), suggesting that satellite arrays undergo rapid evolution through expansions, contractions, gene conversions, and transpositions. Monomers of satellite repeats range in length from 5 bp in Drosophila to 1,419 bp in cattle although more than half of described monomers in 282 species have lengths between 100 and 200 bp, often regarded as approximately the length of nucleosomal DNA (6, 9). The cenH3 nucleosomes typically occupy only a portion of the satellite repeats, often in discontinuous blocks (7, 1012), and the same or similar repeats often underlie flanking pericentromeric heterochromatin composed of conventional nucleosomes. Some of these repeats, for example African green monkey α-satellite DNA, have long been known to position conventional nucleosomes, resulting in arrays of regularly spaced nucleosomes, said to be translationally phased (1315). Nucleosomes can occupy multiple alternative translational phases on the same satellite (16, 17). Translationally phased nucleosomal arrays have also been observed on satellites in cucumber and in several cereal species, where phasing varies among repeats and chromosomal regions (18, 19).Recently deep-sequencing technology has been applied to centromeres treated with micrococcal nuclease (MNase), which preferentially digests linker DNA between nucleosomes, to determine the positioning of cenH3 nucleosomes on satellite repeats. In human cultured cells, substantial translational phasing of CENP-A, the human cenH3, was reported on α-satellite (20). In maize, a similar approach mapped CENH3 (the name used for plant cenH3s) on the 156-bp maize centromeric satellite CentC and on two retrotransposon-derived centromeric sequences, CRM1 and CRM2 (21). Evidence for translational phasing of CENH3 on CentC and CRM1 was lacking, but 190-bp phasing was observed on CRM2. CentC was shown to have a strong periodicity of AA or TT dinucleotides about every 10 bp, which corresponds to one turn of the DNA double helix. This periodicity is thought to favor a particular orientation of the DNA toward the nucleosome core particle, based on DNA bendability, and is known as rotational phasing of nucleosomes (2224).Rice has centromeres characterized by the 155-bp satellite sequence CentO, which is related to maize CentC (25, 26). Although some rice centromeres have megabases of CentO satellites, other evolutionarily new centromeres have little CentO, so CENH3 nucleosomes are found on both CentO and non-CentO sequences (12). For example, Cen8 is comprised of mostly non-CentO sequences and has a CentO array (CentO_8) that is spanned by a sequenced BAC (27). Centromeres like Cen8 are thought to represent an intermediate stage in centromere evolution between rare neocentromeres that form on unique sequences and mature centromeres populated by megabase-sized arrays of satellites (7, 12). Cen8 therefore presents an opportunity to compare the organization of CENH3 nucleosomes on CentO and non-CentO sequences. To that end, we used an antibody to rice CENH3 (27) to perform chromatin immunoprecipitation (ChIP) of CENH3 nucleosomes digested with MNase and sequenced the bound DNA (ChIP-Seq) to determine the positions of CENH3 nucleosomes on rice centromeres. We analyzed the sizes and positions of CENH3 nucleosomal DNA fragments on both CentO and non-CentO sequences to address the role of satellites in organizing centromeric chromatin and analyzed the sequence features of these fragments to look for evidence of nucleosome positioning signals.  相似文献   
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