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271.
We reviewed all ketamine-positive deaths (87) examined at the New York City Office of Chief Medical Examiner over a two-year period (1997 to 1999). There were 15 non-hospital deaths with 12 due to acute multidrug intoxications, one due to sarcoidosis, and two due to physical injury (blunt and thermal). In no instance was a fatal intoxication caused exclusively by ketamine. Opiates (10/15), followed by amphetamines (7/15) and cocaine (6/15), were the most frequent co-intoxicants. Ethanol was found in only one death. The race of all decedents was white and the majority were men (11/15) between the ages of 18 and 30 years. The remaining 72 instances of positive ketamine findings were hospital deaths following surgical procedures or burns.  相似文献   
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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   
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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   
277.
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   
278.
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   
279.
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   
280.
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   
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