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911.
PowerPlex^TM16体系OL等位基因序列分析及命名探讨   总被引:3,自引:0,他引:3  
Lu HL  Tai YC  Liu C  Li HY 《法医学杂志》2006,22(3):186-189
目的观察中国汉族人群PowerPlexTM16体系STR基因座分型标准物外等位基因(OL等位基因)的序列组成,探讨其类型及命名。方法应用PowerPlexTM16体系和ABI377或3100遗传分析仪,对10071名中国汉族无关个体的血样DNA进行15个STR基因座的分型,筛选出OL等位基因样本;对该样本进行单基因座扩增、聚丙稀酰胺凝胶电泳、银染显色,获取等位基因条带并再次扩增和测序。结果在11个基因座检见OL等位基因,共32个,频率0.05‰ ̄4.02‰,各基因座OL等位基因数目1 ̄9个不等。按其组成分为四类:(1)重复单位完整重复,但重复次数在ladder范围外;(2)不完整重复;(3)侧翼序列个别碱基的插入或缺失;(4)较大片断的缺失。结论OL等位基因类型不一,既有重复次数的变化,也有侧翼序列或核心序列的变化,现有命名原则尚不能反映其组成类型。  相似文献   
912.
913.
The 17 Y-chromosomal short tandem repeats (STRs) included in the AmpFLSTR Yfiler PCR Amplification Kit (AB Applied Biosystems) (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, DYS635 and GATA H4) were typed in two Berber communities, a small village (Takrouna) and a town (Sejenane), from North Tunisia. As expected, diversity was higher in the town, even when compared with a pool of three small Berber communities, probably due to the combination of different founder effects and genetic drifts operating in the small villages.  相似文献   
914.
915.
The analysis of genetic variation in the nucleotide sequences of mitochondrial DNA has been used as a tool in the study of history of different human populations, as Amerindians, Afro-descendents populations and furthermore admixed populations. In this study, the mitochondrial DNA was analyzed in 158 unrelated individuals in an admixed population of the Amazonian Region: Santarém-PA-Brazil. The polymorphisms were detected using both levels, analysis of restriction enzyme and direct sequencing. We observed a total of 49 different haplotypes were found determined by 46 variable nucleotides. The more frequent haplotypes (Hap03) was shared by five samples and 43 sequences were unique. The genetic diversity was estimated to 0.989+/-0.0067 and the probability of two random individuals showed identical mitochondrial DNA (mtDNA) haplotypes were 2.8%.  相似文献   
916.
The new method exploits the characteristic of staphylococcal protease V8, which specifically splits peptide bonds where l-glutamic or l-aspartic acid participate. Those peptide bonds where d-aspartic acid is present remain unsplit because of the stereospecifity of enzymes. In accordance with expectations, fewer peptide bonds are split by this protease at more advanced ages and larger peptide fragments are thus formed due to the higher content of d-amino acid residues in the proteins of older people. The samples of acid-extracted non-collagenous proteins from dentin were separated using high performance liquid chromatography after enzymatic hydrolysis. A peak with a retention time of 45.3 min was chosen and his enlarging area showed a linear correlation with increasing age. Although the linear correlation with age was proved, the scattering of values decreases the usefulness of the proposed method for age estimation.  相似文献   
917.
Infections are considered to be an important cause of unexpected death in children. It has also been assumed that respiratory viruses are involved in the genesis of sudden infant death syndrome (SIDS). The Spanish National Institute of Toxicology and Forensic Sciences act as the forensic reference centre for Spain. We analyse the experience of this centre in the virological study of 64 cases of sudden children death where viral serology, virological cultures, herpesviruses polymerase chain reaction (PCR) and electron microscopy were performed. According to pathological findings, death could only be attributed to an adenovirus infection in one amygdalitis with upper airways stenosis and asphyxia. Human herpes virus 6 (HHV-6) was detected by PCR in one case with pathological findings characteristic of SIDS. Recent infection by respiratory syncytial virus (RSV), Epstein-Barr virus (EBV) and cytomegalovirus (CMV) were also detected. Meanwhile, 85.9% of the cases yielded negative viral results. Twenty-eight infants were finally categorised as SIDS. Pathological findings of infection were detected in 12 patients despite the negativity of viral analyses. Although viral infection is an uncommon cause of sudden children death, a complete microbiological investigation will help to solve the puzzle of SIDS. Definitive guidelines for microbiological analyses need to be updated whilst new pathogens are discovered or new techniques are implemented in order to clarify unsolved cases.  相似文献   
918.
This study aimed to know the prevalence of sexual coercion toward women perpetrated by acquaintance Spanish college men, and some personal factors associated with the involvement in these behaviors to replicate the confluence model. An anonymous questionnaire was completed by 196 university students that included an adaptation of the Sexual Experiences Survey, and other scales to assess different attitudes, motives, and experiences associated with sexual aggression. About 15% of men admitted some involvement in sexual behaviors when the woman did not want it. The control and dominance needs, the personal disposition to impersonal sex, and empathy competency showed the strongest association with the involvement in coercive sexual behaviors. Empathy moderated the effects of control and domination needs and the impersonal sex in predicting sexual coercion. Overall, our data supports the confluence model.  相似文献   
919.
Preparation of degraded human DNA under controlled conditions   总被引:7,自引:0,他引:7  
DNA typing through analysis of short tandem repeats (STRs) and mitochondrial DNA (mtDNA) by means of the polymerase chain reaction (PCR) and sequencing are the common methods for the forensic identification of persons and reconstruction of kinship, especially when skeletal human remains have to be analyzed. Furthermore, samples typically found at crime scenes may be both quantitatively and qualitatively inadequate since they may contain very scarce and often degraded DNA due to exposure to heat, light, humidity, and microorganisms. In order to improve the performance of STR typing technology in those cases where DNA availability is limited, it would be desirable to have a source of degraded DNA with known properties. For this purpose, we have developed a method to prepare artificially degraded DNA under controlled conditions. By treatment of genomic DNA with sonication and DNAse I we have produced DNA fragments within a defined range of lengths. STR typing of this degraded DNA with a commercially available multiplex kit could only produce partial profiles as indicated by the absence of STR alleles with sizes >200 bp. This artificially degraded DNA can be used for the improvement and standardization of STR typing protocols when only highly degraded DNA is available for analysis.  相似文献   
920.
服刑能力影响因素研究   总被引:3,自引:1,他引:2  
Huang FY  Lu CR  Zhang QT  Cai W  Guan W  Wu J  Wang J 《法医学杂志》2004,20(4):218-220
目的探索精神病犯服刑能力的影响因素,为服刑能力量化评定奠定基础。方法以江苏省监狱管理局精神病院2003年11月1日~2003年12月31日期间住院及新入院病人为研究对象,采用RTHD和自编的服刑能力法律心理能力问卷和服刑相关情况调查表,从医学要件和法学要件两方面探索服刑能力影响因素。结果共纳入185例研究对象,分为有或无服刑能力两组,在一般状态、认知障碍、情感症状和行为异常等方面均存在显著差异,自知力对服刑能力具有显著影响,两组社会功能也存在显著差别;虽然研究对象入院时表现行为紊乱、言语紊乱、情绪低落甚至出现自杀、自伤、精神运动性迟滞,生活不能自理、易激惹、冲动伤人、劳动能力下降等明显异常,但对问卷的分析没有体现出这种异常。结论在精神症状的影响下,精神病犯表现出明显异常,辨认和控制能力明显受损,不能正常接受服刑改造。  相似文献   
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