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121.
122.
A simple and rapid method for direct simultaneous determination of amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA), 3,4-methylenedioxy-N-ethylamphetamine (MDEA) and N-methyl-1-(3,4-methylenedioxyphenyl)-2-butanamine (MBDB) in seized tablets was developed using gas chromatography with flame ionization detection. Separation of all six underivatized amphetamines, including diphenylamine as internal standard, was performed in about 6 min, using SPB-50 capillary column. Amphetamine and methamphetamine eluted with negligible tailing while the other amphetamines had highly symmetrical peaks. Sensitivity per component on-column was in the nanogram range, and reproducibility from 2.6 to 6.6% at low concentration (2.4 microg/mL) and from 1.2 to 2.6% at high (70 microg/mL) concentration. The method has a wide linear range, from Limit of detection (LOD) to almost 200 microg/mL, thus allowing analysis of different samples across a wide range of possible concentrations of amphetamines. This simple, fast and precise method using gas chromatography--flame ionization detector (GC--FID), in conjunction with other methods (TLC, IR, HPLC), can be used for identification of amphetamines and direct determination in seized tablets, especially in laboratories with heavy workload.  相似文献   
123.
Allele frequencies for the fifteen short tandem repeats (STR) loci D3S1358, vWA, FGA, D8S1179, D21S11, D18S51, D5S818, D13S317, D7S820, D19S433, THO1, D16S539, CSF1PO, TPOX, D2S1338 (AmpFl STR Identifiler PCR Amplification Kit, Applied Biosystems) were determined in a population sample of unrelated China Han in Jilin Province, China. Statistical analyses were performed using Powerstats version 1.2 and GEP-ISFGWG. The results showed that all the loci met Hardy-Weinberg expectation.  相似文献   
124.
A total of 201 males from Somalia were typed for the Y-chromosome STRs DYS19, DYS385a/b, DYS389-I, DYS389-II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438 and DYS439 with the PowerPlex Y kit (Promega). A total of 96 different haplotypes were observed and the haplotype diversity was 0.9715. The number of unique haplotypes was 71 while the most common haplotype was observed 24 times.  相似文献   
125.
The medicolegal and subsequent criminologic interpretation of forensic and pathological findings in cases of homicide makes up an important tool of case profiling. In a retrospective study of 26 cases of "multiple homicides" involving 31 perpetrators (30 males, 1 female, mean age 33.5 years) and 73 victims (33 males, 40 females, mean age 36 years, 68 fatalities, 5 survivors), autopsy reports and prosecution authorities' files were investigated with regard to individual characteristics of victims and offenders, circumstances as well as mode of commitment. The major aim of this study was to comprehensively elucidate and characterise relevant forensic and criminologic features, which may gain importance for forensic case profiling. Forty-six victims were found in the close social environment of the perpetrator and 45 homicides were committed either in the victim's, the perpetrator's or the shared domicile. The main motives included concealment of a crime (n=13), personal conflicts/domestic arguments (n=7) and greed (n=12). The relevant injuries with regard to the cause of death were attributable to sharp force (n=13), blunt force (n=7), gunshot wounds (n=24), ligature strangulation (n=3), smothering (n=5), fire/carbon monoxide (n=4) and combined impacts (n=11). In 15 cases, so called defence injuries were found. In 5 victims a post-mortem blood alcohol concentration >1.5 g/l was determined. In six perpetrators, a severe psychiatric impairment of juridical responsibility was ascertained (Section 20 German criminal code, n=2, psychosis; Section 21 German criminal code, n=4, acute alcohol intoxication). As far as conviction data were available, 27 crimes were juridically assessed as murder, 12 as manslaughter and one as bodily harm with fatal consequences.  相似文献   
126.
Dog DNA-profiling is becoming an important supplementary technology for the investigation of accident and crime, as dogs are intensely integrated in human social life. We investigated 15 highly polymorphic canine STR markers and two sex-related markers of 131 randomly selected dogs from the area around Innsbruck, Tyrol, Austria, which were co-amplified in three PCR multiplex reactions (ZUBECA6, FH2132, FH2087Ua, ZUBECA4, WILMSTF, PEZ15, PEZ6, FH2611, FH2087Ub, FH2054, PEZ12, PEZ2, FH2010, FH2079 and VWF.X). Linkage testing for our set of marker suggested no evidence for linkage between the loci. Heterozygosity (HET), polymorphism information content (PIC) and the probability of identity (P((ID)theoretical), P((ID)unbiased), P((ID)sib)) were calculated for each marker. The HET((exp))-values of the 15 markers lie between 0.6 (VWF.X) and 0.9 (ZUBECA6), P((ID)sib)-values were found to range between 0.49 (VWF.X) and 0.28 (ZUBECA6). Moreover, the P((ID)sib) was computed for sets of loci by sequentially adding single loci to estimate the information content and the usefulness of the selected marker sets for the identification of dogs. The estimated P((ID)sib) value of all 15 markers amounted to 8.5 x 10(-8). The presented estimations turned out to be a helpful approach for a reasonable choice of markers for the individualisation of dogs.  相似文献   
127.
A total of 185 unrelated Danish males were typed for the Y-chromosome STRs DYS19, DYS385a/b, DYS389-I, DYS389-II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438 and DYS439 using the kits PowerPlex Y (Promega), ReliaGene Y-Plex 6 and ReliaGene Y-Plex 5 (Reliagene Technologies). A total of 163 different haplotypes were observed and among these, 144 haplotypes were unique. The gene diversity was 0.9985. In DYS392, a variant allele migrating as a 10.2 allele was observed. Sequencing of the allele showed a deletion upstream the repeated area.  相似文献   
128.
129.
Gimbel B 《Newsweek》2004,143(18):62-63
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130.
Degradation of human DNA extracted from forensic stains is, in most cases, the result of a natural process due to the exposure of the stain samples to the environment. Experiences with degraded DNA from casework samples show that every sample may exhibit different properties in this respect, and that it is difficult to systematically assess the performance of routinely used typing systems for the analysis of degraded DNA samples. Using a batch of artificially degraded DNA with an average fragment size of approx. 200 bp a collaborative exercise was carried out among 38 forensic laboratories from 17 European countries. The results were assessed according to correct allele detection, peak height and balance as well as the occurrence of artefacts. A number of common problems were identified based on these results such as strong peak imbalance in heterozygous genotypes for the larger short tandem repeat (STR) fragments after increased PCR cycle numbers, artefact signals and allelic drop-out. Based on the observations, strategies are discussed to overcome these problems. The strategies include careful balancing of the amount of template DNA and the PCR cycle numbers, the reaction volume and the amount of Taq polymerase. Furthermore, a careful evaluation of the results of the fragment analysis and of automated allele calling is necessary to identify the correct alleles and avoid artefacts.  相似文献   
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