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排序方式: 共有6821条查询结果,搜索用时 31 毫秒
141.
目的研究D2S1399和D5S2500基因座在中国华东地区汉族群体遗传多态性。方法应用PCR、聚丙烯酰胺垂直电泳及银染技术检测D2S1399和D5S2500基因座的遗传多态性。结果D2S1399和D5S2500基因座在中国华东汉族群体分别检出11个和9个等位基因,其观察杂合度(Ho)分别为0.745和0.807,多态信息含量(PIC)分别为0.850和0.750,个体识别能力(DP)分别为0.958和0.917,非父排除率(PE)分别为0.554和0.643。结论D2S1399和D5S2500两个基因座是高度多态性STR基因座,在法医学中有重要应用价值。 相似文献
142.
Richard?RogersEmail author Mandy?J.?Jordan Kimberly?S.?Harrison 《Law and human behavior》2004,28(6):707-718
The development of standardized assessments for competency-to-confess evaluations has remained largely neglected for the last several decades. Groundbreaking research was conducted on Miranda waivers during the late 1970s, but researchers have failed to sustain programmatic research. This critical review focuses on four published Miranda measures (Comprehension of Miranda Rights, Comprehension of Miranda Rights-Recognition, Comprehension of Miranda Vocabulary, and Function of Rights in Interrogation). When evaluated by contemporary standards, the validation of these measures is very limited. Major improvements are needed for interrater reliability, test–retest reliability, content validity, construct validity, and criterion-related validity. 相似文献
143.
骨骼种属鉴定的组织学研究 总被引:6,自引:1,他引:5
目的 探求骨骼残渣的种属鉴定的组织学方法。方法 对人体不同部位骨骼,及常见动物骨骼的 77张骨组织学切片,在光镜下进行了骨组织学形态学研究。结果 不同动物骨组织学的形态学特征存在明显差异,其主要差别有:内、外环骨板的形态和相对厚度;哈氏系统之间的骨板的形态和哈氏系统的大小;哈氏环层骨板的数量及骨陷窝的数量等。结论 骨组织学的特征,不仅可以区分人与动物骨骼的残渣,也可以对不同动物的骨骼残渣进行区分。 相似文献
144.
甲基苯丙胺稀土荧光试纸条的研制 总被引:1,自引:1,他引:0
目的建立一种检测尿液中甲基苯丙胺物质的高灵敏度检测方法。方法以稀土荧光纳米颗粒为标记物,采用反应杯+试纸条的反应模式,建立了免疫层析法,用于尿液中甲基苯丙胺的定性检测。结果用所制备的试纸条检测尿液中的甲基苯丙胺,肉眼和仪器判读的敏性均为100ppb,与吗啡、亚甲二氧基苯丙胺、氯胺酮、苯丙酮、可卡因等无交叉反应;将制备的反应杯和试纸条置于37℃7d,试纸条的性能没有明显降低。结论本研究建立的甲基苯丙胺免疫层析法用于定性检测尿液中的甲基苯丙胺,具有较高的灵敏性和较高的应用价值。 相似文献
145.
Shane Darke Ph.D. Johan Duflou M.Med.Path. F.R.C.P.A. Michelle Torok B.Soc.Sc. 《Journal of forensic sciences》2009,54(2):490-494
Abstract: To determine the prevalence and circumstances of psychoactive substances amongst nonoverdose completed suicide, 1436 consecutive cases autopsied at the NSW Department of Forensic Medicine over the period 1/1/1997–12/31/2006 were analyzed. Substances were detected in 67.2% of cases, and illicit drugs in 20.1%. Alcohol was present in 40.6% of cases. Males were more likely to be positive for alcohol, cannabis, and psychostimulants, and females for pharmaceuticals. Illicits were associated with younger age. Alcohol was most prominent amongst toxicity cases, as were opioids, psychostimulants amongst gunshot cases, and pharmaceuticals amongst drownings. Cases in which drug and alcohol histories were noted were more likely to have a substance detected. Alcohol was more common where a suicide note was left and where relationship problems were involved. Pharmaceuticals were more common where a previous attempt was noted. Licit and illicit substances are strongly associated with suicide, even when the method does not involve drug overdose. 相似文献
146.
目的建立高效液相色谱-质谱法测定人尿液中乙基葡萄糖醛酸苷。方法取空白人尿液加入EtG-D5内标工作液和冷甲醇(4℃),经涡旋、离心,取上清液于水浴氮气吹干,以沉淀杂质,采用Agilent Zorbax Bonus-RP色谱柱分离,以乙腈∶0.1%甲酸水溶液(5∶95)为流动相,采用负离子模式质谱检测,在选择离子监测模式下进行定性和定量测定。结果尿液中EtG在50~5 000ng/mL范围内线性关系良好,检出限为18ng/mL,方法回收率为90.2%~101.7%,相对标准偏差小于10%。结论所建方法简便,具有较高的回收率和精密度,适用于尿液中EtG的检测。 相似文献
147.
根据MongoDB文件型数据库的特点,提出了一种针对MongoDB文件型数据库的证据获取方法。在研究GridFS文件系统原理的基础上,详细阐述了MongoDB和GirdFS文件系统结构,对MongoDB存放数据的文件进行了分析,进而获取被删除的文件数据。实验结果表明该方法能有效地从MongoDB数据库中获取电子证据。 相似文献
148.
Abstract: A new screening method for detecting gamma-hydroxybutyric acid (GHB) in drink matrices, using the IonSense, Inc. (Saugus, MA) direct analysis in real time (DART) ion source coupled to a JEOL exact mass time-of-flight mass spectrometer (AccuTOF), was validated and compared with the current screening methodology. The DART ion source allows for analysis of samples under ambient conditions with little to no sample preparation. Fifty drink specimens were spiked at levels of 1, 2, 3, and 4 mg/mL GHB, and analyzed on the AccuTOF-DART. Positive detection of GHB occurred for each of the samples at each concentration level, giving 100% accuracy for the samples tested. Twenty-five of the 50 drink specimens were spiked at 1 mg/mL GHB and tested using a color test known as the GHB Color Test #3. Only two of these 25 specimens tested positive for the presence of GHB, giving only 8% accuracy. Implementation of this new methodology as a screening tool for GHB analysis will quickly eliminate negative specimens allowing the examiner to focus analysis time on those that screened positive. 相似文献
149.
目的建立以固相萃取-高效液相色谱(SPE-HPLC)分析大鼠血浆中灭多威的方法。方法以空白大鼠血浆添加灭多威标准品及内标物,以SPE法对样品进行前处理,采用HPLC进行分析,考察仪器测试条件、特异性、回收率、灵敏度、精密度、准确度、线性关系、稳定性,并对方法进行优化。结果采用本文方法测得灭多威在血浆中的线性范围0.1-20μg/mL(r=0.9993,P〈0.001),血浆中的检测限0.03μg/mL(S/N≥3),日内、日间精密度的CV值分别在8.33%与11.11%以内,日内、日间准确度值分别在90%与120%之间,回收率值在88%±4.4%以上。结论所建方法实用、便捷,可对血浆中的灭多威进行定性定量地快速测定。 相似文献
150.
Kris Mohandie Ph.D. J. Reid Meloy Ph.D. A.B.P.P. Peter I. Collins M.C.A. M.D. F.R.C.P. 《Journal of forensic sciences》2009,54(2):456-462
Abstract: The frequency and characteristics of suicide by cop cases (SBC) among a large (n = 707) nonrandom sample of North American officer-involved shootings (OIS) were investigated. “Suicide by cop” is when a subject engages in behavior which poses an apparent risk of serious injury or death, with the intent to precipitate the use of deadly force by law enforcement against the subject. Thirty-six percent of the OIS in this sample were found to be SBC with high interrater agreement (intraclass correlation coefficient = 0.93) for category classification. SBC cases were more likely to result in the death or injury of the subjects than regular OIS cases. Most SBC cases were spontaneous, but had clear verbal and behavioral indicators that occurred prior to, and during the event. Findings confirm the trend detected in earlier research that there was a growing incidence of SBC among OIS. SBC individuals had a high likelihood of possessing a weapon (80%), which was a firearm 60% of the time. Half of those with a firearm discharged it at the police during the encounter. Nineteen percent simulated weapon possession to accomplish their suicidal intent. Other findings highlight the histories and commonalities in this high risk group. 相似文献