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排序方式: 共有160条查询结果,搜索用时 15 毫秒
1.
This study evaluated the genetic variation of 17 autosomal short tandem repeat (STR) loci included in the PowerPlex® 18D Kit. Samples of 562 unrelated healthy Lahu individuals living in Yunnan Province in southwestern China were investigated. The data were analyzed to provide information on allele frequencies and other statistical parameters relevant to the forensic population. Of the 17 loci, 16 reached the Hardy–Weinberg equilibrium after Bonferroni correction. A total of 176 alleles were identified in 17 STR loci, and allele frequencies ranged from 0.000 890 to 0.578 292. The combined discrimination power (CPD) and probability of excluding paternity (CPE) of the 17 STR loci were 0.999 999 999 999 999 999 489 and 0.999 998 301 753 122. The genetic relationships among 28 populations were also estimated.  相似文献   
2.
作者以体模实验为基础。测定了不同管电压拍摄胸片时的病人剂量,考察了提高管电压对胶片影像质量的影响,结果表明,使用高电压拍摄胸片比使用低电压有利于降低病人剂量,在增加影像信息量,提高肋骨阴影区和纵膈区灶检出率方面更有较大优越性,此外,使用高电压技术不家利于延长X射线管的使用寿命。  相似文献   
3.
对雄性Wisiaf大鼠腹腔1次注射碘-13l, 注入活度分别为0.59×104Bq,2.37×104Bq, 4.34×104Bq, 8.23×104Bq, 碘-125注入活度分别为3.7×104Bq, 7.4×104Bq, 14.8×104Bq, 22.2×104Bq.碘-131诱发肿痛实际注入活度在2.37×104Bq以下,碘-125的为7.4×104以下.诱发的肿瘤以甲状腺肿瘤为主,其次为垂体肿瘤.  相似文献   
4.
周围剂量当量仪研制是根据国际辐射单位和测量委员会(ICRU)39号报告推荐的周围剂量当量而设计的一种数字化智能型辐射防护仪。方法采用能量补偿对探测器进行能响校正。结果补偿结果使得探测器在47~230keV与ISO推荐的H*(10)/Ka值误差在5%以内。本文重点描述了周围剂量当量仪探测器部分的工艺结构和剂量学性能以及电子学测量部分的主要功能。结论通过实际应用我们初步获得的结论是由于该仪器可直接测量周围剂量当量,稳定性好且具有自动取平均值特点,它可做为实验室校准用测量仪器,又由于该仪器体积小,电池供电,读数面板又有背光功能,它也可以做为现场仪器用于辐射防护实践的现场测量  相似文献   
5.
目的 研究应用计算机数据库技术及先进统计分析方法,对阳江高本底地区10多万人20余年的健康随访研究资料和剂量学调查资料进行储存、管理和分析。方法 通过调研和比较分析,确定采用Foxbase系列数据库管理系统按专题建立数据库,借助于ID号实现记录连接;一般统计分析由SAS完成;交叉分组人年列表由Epicure中的Datab完成;癌症相对危险分析用AMFIT程序。结果 建立了40MB的各专题研究库,主要包括:10余万人的人口学数据库(1979~1995)、1.2万人的死因数据库(1979~1995)和526个村庄6783户、5273人的剂量数据库。提出了动态群组研究资料(1979~1986)与固定群组研究资料(1987~1995)的合并方法:首选方法是建立假想的基于记录连接的以1979年为起点的(固定)群组。另一方法是将不同阶段群组研究的人年表分层直接相加。计算了每个成员基于卧室内、起居室内、室外村平均剂量率与性别-年龄别居留因子的累积剂量。完成了以性别、atainedage、随访年代及剂量交叉分组的人年列表,对癌症死亡资料(1979~1990)进行了危险分析。结论 应用计算机数据库管理系统与统计分析技术使阳江高本底地区研  相似文献   
6.
本文报道了白云矿矿工肺内天然钍沉积量及其对健康影响的10年(1982年~1991年)研究的结果。结果。本研究采用改进了的高灵敏度负高压静电收集氧子体装置,对该矿588名接尘矿工985人次和124名非钍尘作业人员的呼出气中作氧活度的测定,前者肺内钍的平均值为0.85Bp(23.06pCi)后者肺内钍的平均值为0.15Bp(4.05pCi).接尘矿工被检者中44.4Bq(120pCi)者5人;最高的1人为5.56Bp(150pCi),经修正最高值应为11.11Bp(300pCi)。  相似文献   
7.
Objective: We investigated the application of 51 autosomal short tandem repeat (STR) loci with the identity by state (IBS) method and a discriminant function algorithm in full-sib identification. Methods: A total of 342 pairs of full sibs (FSs) and 3900 pairs of unrelated individuals (UIs) were genotyped for 51 STR loci. Groups were formed in accordance with discrimination power (DP) values and the number of loci, and IBS scores of FSs and UIs were analyzed and compared. The discriminant functions of FS-UI were determined by using the Fisher discriminant with SPSS software. Results: All IBS in FSs and UIs groups showed normal distributions and there were significant differences between FS-UI. Receiver operating characteristic curves revealed that the detection efficiency of full-sib identification was affected by both the locus polymorphism and the number of loci detected. Comparing the rate of false positive and false negative of discriminant function between groups, a higher average DP value and larger number of loci detected were associated with a lower rate of miscarriage of justice and were more helpful for full-sib identification. Conclusion: STRs with higher DP values should be selected when additional autosomal markers are required for FS identification. Discriminant analysis with the IBS method is highly applicable for the FS-UI test.  相似文献   
8.
A maternity testing case is reported, in which the child showed tri-allelic patterns in two short tandem repeat (STR) loci. The genotypes of Penta D of the mother and the child were 9,13 and 9,10,13, respectively. Those of D21S11 were 32.2,35 and 29,35, respectively, but intensity ratio of alleles 29 and 35 of the child was 1:2. These results suggested the copy number variations (CNVs) or trisomy of chromosome 21. By further examination using STR-based chromosome aneuploidy detection kit, three alleles were detected in D21S1411, LFG21 and Penta D, and 2 alleles with intensity ratio of 1:2 were observed in D21S2502, D21S1435, D21S11 and D21S1246. Karyotype and whole-genome SNP array analyses showed that the child had a free trisomy 21. In addition, partially homologous non-sister chromatid crossover occurred at the region 19181770-39499178 on the long arm of chromosome 21.  相似文献   
9.
10.
In this study, we examine the potential for using face imaging sensing technology in place of a human forensic practitioner to estimate the age of cadavers. We used the age estimation software FieldAnalyst for Signage Ver. 6.0 AW32. To validate the usefulness of its age estimation for living subjects, images of 28 subjects were taken at three angles (+30°, 0°, and −30°) with respect to the horizontal plane, with their eyes open and closed. The highest positive correlation between mean the estimated age and the actual age (y = 1.02x − 0.35, and Spearman’s rank correlation coefficient of 0.78, P < 0.001) was obtained when the subjects had their eyes closed and the image was captured at an angle of 0°. The ages of 93% of the subjects were estimated within ±10 years of their actual ages. We then applied this procedure to 61 cadavers with their eyes closed. Facial images were taken at an angle of 0° with respect to the horizontal plane and used to estimate the ages of the cadavers. Although a positive correlation between the actual and mean estimated ages was obtained (y = 1.28x + 0.43, Pearson’s correlation coefficient of 0.69, P < 0.001), the mean estimated ages of only 39.3% of the subjects were within ±10 years of their actual ages. It appears that this technology is not accurate enough to use to determine the age of a cadaver. Therefore, medical inspectors with adequate knowledge and experience are still required for postmortem examination.  相似文献   
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