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991.
Zhe Chen Jianting Cao Yang Cao Yue Zhang Fanji Gu Guoxian Zhu Zhen Hong Bin Wang Andrzej Cichocki 《Cognitive neurodynamics》2008,2(3):257-271
Electroencephalogram (EEG) is often used in the confirmatory test for brain death diagnosis in clinical practice. Because
EEG recording and monitoring is relatively safe for the patients in deep coma, it is believed to be valuable for either reducing
the risk of brain death diagnosis (while comparing other tests such as the apnea) or preventing mistaken diagnosis. The objective
of this paper is to study several statistical methods for quantitative EEG analysis in order to help bedside or ambulatory
monitoring or diagnosis. We apply signal processing and quantitative statistical analysis for the EEG recordings of 32 adult
patients. For EEG signal processing, independent component analysis (ICA) was applied to separate the independent source components,
followed by Fourier and time-frequency analysis. For quantitative EEG analysis, we apply several statistical complexity measures
to the EEG signals and evaluate the differences between two groups of patients: the subjects in deep coma, and the subjects
who were categorized as brain death. We report statistically significant differences of quantitative statistics with real-life
EEG recordings in such a clinical study, and we also present interpretation and discussions on the preliminary experimental
results.
相似文献
Zhe ChenEmail: |
992.
Ho PY Huang MZ Fwu VT Lin SC Hsiao KJ Su TS 《Biochemical and biophysical research communications》2008,373(4):515-520
To simultaneously assess the effects of exonic mutations on RNA splicing and protein functions, we report here an intron-inclusive cDNA (Intinc) expression system. As a test model, twenty-four mutations in exon 9 of the phenylalanine hydroxylase (PAH) gene were examined in an Intinc expression plasmid composed of the PAH cDNA with the exon 9 flanked by its authentic introns. When the PAH enzyme activities from the Intinc plasmid-transfected cells were compared to those of a standard cDNA expression system, five mutations resulted in significant relative differences in PAH activities attributed to altered exon 9-inclusive mRNA levels. Two of the mutations affected exon recognition probably through splice site modifications and the remaining three affected experimentally verified exon splicing enhancer (ESE) motifs. The Intinc expression system allows not only a better link between mutation genotype to disease phenotype but also contributes to further understanding of molecular mechanisms of deleterious effects of mutations. 相似文献
993.
过去十年,在禄丰古猿地点作了多次的发掘和筛洗,采集到包括食虫类,翼手类,啮齿类和兔形类在内的一千余件标本,使这一小哺乳动物的化石组合从1979年首次报道的6种增加到了38种,成为我国南方新第三纪中期最丰富而有代表性的小哺乳动物群。材料的初步鉴定表明:动物群中有代表我国首次发现的化石科和属;并有相当数量与华北、印巴次大陆和欧洲有密切亲缘关系的类型;其地质时代属最晚中新世保德期,相当于欧洲陆相哺乳动物分期的土洛里期(Turolian)。 相似文献
994.
995.
996.
担子菌多糖及羊脾RNA对肿瘤的抑制与有关组织中cAMP含量关系的探讨 总被引:1,自引:0,他引:1
本文讨论了对带瘤小鼠注射香菇多糖、松口蘑多糖和羊脾RNA后,活体内有关组织中cAMP含量与抑瘤率之间的关系。 结果表明,上述活性物质不仅增强了机体免疫活性,同时亦促使机体内脾、瘤等组织的cAMP增高,此种增高,与抑瘤率成正相关。 相似文献
997.
998.
Xinxin Wang Liang Wu Ping Zhou Shengfeng Zhu Wei An Yu Chen Lin Zhao 《World journal of microbiology & biotechnology》2013,29(11):2015-2024
The codon usage patterns of rhizobia have received increasing attention. However, little information is available regarding the conserved features of the codon usage patterns in a typical rhizobial genus. The codon usage patterns of six completely sequenced strains belonging to the genus Rhizobium were analysed as model rhizobia in the present study. The relative neutrality plot showed that selection pressure played a role in codon usage in the genus Rhizobium. Spearman’s rank correlation analysis combined with correspondence analysis (COA) showed that the codon adaptation index and the effective number of codons (ENC) had strong correlation with the first axis of the COA, which indicated the important role of gene expression level and the ENC in the codon usage patterns in this genus. The relative synonymous codon usage of Cys codons had the strongest correlation with the second axis of the COA. Accordingly, the usage of Cys codons was another important factor that shaped the codon usage patterns in Rhizobium genomes and was a conserved feature of the genus. Moreover, the comparison of codon usage between highly and lowly expressed genes showed that 20 unique preferred codons were shared among Rhizobium genomes, revealing another conserved feature of the genus. This is the first report of the codon usage patterns in the genus Rhizobium. 相似文献
999.
1000.
筛选鉴定一株产生抑菌活性物质的海洋放线菌 总被引:1,自引:0,他引:1
目的:分离筛选能够产生抑菌活性物质的海洋放线茵,并进行生理生化和16SrDNA鉴定。方法:用分离培养基培养海洋放线菌,并筛选出能够产生抑菌活性物质的菌株,对所筛选菌株的形态特征、生理生化特性进行鉴定分析;采用通用引物27F、1492R扩增该菌株的16SrDNA,对测序结果进行分析;采用Neighbor—Joining(N—J)法构建系统发育进化树。结果:筛选到一株对金黄色葡萄球菌、大肠杆菌、白色念珠菌具有较强抗性的海洋放线菌F1,该菌株好氧,中度嗜盐,在高氏I号培养基上呈白色绒粉状,16SrDNA序列比对表明该菌株与田无链霉菌(Streptomyces tanashiensis)NR043369的相似度为99%。结论:筛选到的菌株F1是一株海洋来源的放线菌,与田无链霉菌NR043369的同源性较高,可能属海洋链霉菌属,对金黄色葡萄球菌等病原菌具有较强的抑菌活性。 相似文献