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991.
992.
Electrospray ionization (ESI) and matrix-assisted laser desorption/ionization (MALDI) mass spectrometry have been used to examine evidence in a sexual assault investigation. Because condoms are being used increasingly by sexual assailants and some condom brands include the spermicide nonoxynol-9 (nonylphenoxy polyethoxyethanol) in the lubricant formulation, the recovery, and identification of nonoxynol-9 from evidence items may assist in proving corpus delicti. A method was developed for the recovery of nonoxynol-9 from internal vaginal swabs and for its identification by reverse phase liquid chromatography/electrospray ionization mass spectrometry (LC ESI-MS), nanoelectrospray ionization (nanoESI) mass spectrometry, and high resolution MALDI Fourier transform mass spectrometry (MALDI-FTMS). The method was tested on extracts from precoitus, immediate postcoitus, and four-hours postcoitus vaginal swabs provided by a volunteer whose partner does not normally use condoms, but for this trial used a condom having a water-soluble gel-type lubricant that includes 5% nonoxynol-9 in its formulation. Subsequently, LC ESI-MS was used to identify traces of nonoxynol-9 from the internal vaginal swab of a victim of a sexual assault.  相似文献   
993.
In order to use genetic loci in forensic identity testing, some population data are needed. This paper presents a report of allele frequency data for the loci HUMTH01, HUMTPOX and HUMVWA in a population sample from Northern Spain. No deviation from the Hardy-Weinberg equilibrium was detected in any of the three markers investigated and there was no evidence of association between the alleles of these loci. Statistical analysis was also carried out to obtain some parameters of medicolegal interest and comparative studies were carried out with other populations studied to date for these five loci. The Asturian sample does not differ substantially from other Caucasian and Spanish populations.  相似文献   
994.
Deaths attributed to ingestion of Nicotiana glauca are extremely rare. We report here a case where a 43-year-old man was found dead after apparently drinking a water extract of Nicotiana glauca. The primary alkaloid in the plant is anabasine. Toxicological analysis by capillary gas chromatography showed the deceased had a blood anabasine concentration of 2.2 mg/L. Clinically, the features of poisoning are nicotine-like and if death occurs it results from respiratory paralysis. The case further supports the view that, in the human, anabasine is considerably more toxic than nicotine.  相似文献   
995.
No reliable data are available on cases of lethal child abuse (by active force) in the area of Federal Republic of Germany prior to reunification (the former West Germany). In a multicenter study we therefore examined the police and court records for such cases occurring in the period 1 January 1985 to 2 October 1990 in nearly the entire area of Federal Republic of Germany. RESULTS: The study center received information on 58 cases of lethal child abuse. Extrapolated to all institutes of legal medicine, this corresponds to 62 cases in all of West Germany in the period studied. An approximately equal number of unreported cases should be added to this figure. Including unreported cases, at least 20 cases of lethal child abuse occurred per year; thus only one in every two cases ever came to light. Almost two thirds of the victims were younger than one year old. At autopsy 59% exhibited signs of repeated abuse at autopsy. By far the most common cause of death was direct impact from a blunt object, usually to the head. Mostly, the male person to whom the victim relates most closely (father, stepfather, partner of the mother) has killed the child. Twenty-one of the 74 persons charged saw the charges against them dropped or were acquitted due to lack of evidence; 51 received sentences ranging from one year probation to life. In the remaining two cases the outcome of the trial was unknown. Signs of abuse were readily apparent at autopsy in almost all cases. The high number of unreported cases underscores the need to educate medical students and practicing physicians to be on the look-out for signs of abuse and argues for an increase in the rate of autopsy.  相似文献   
996.
Taphonomy of marine environments has been studied mostly from individual cases. The formation of adipocere, or "grave-wax," is an important indicator of the postmortem interval. In the present paper, the conditions and the timing of adipoceric formation are observed in a series of 15 cadavers recovered at different times, over a period of 433 days, from the same contained environment. Initial foci of adipocere on the subcutaneous tissue of the cadavers were detected as early as 38 days from the time of immersion in cold (10-12 degrees C) sea water. The discrepancies between our findings and previous reports on the correlation between time since death and decomposition stages in marine environments are discussed.  相似文献   
997.
This article describes the application of solid-phase microextraction (SPME) to the recovery of manufacturing by-products and impurities from an illicit drug seizure. The preparation chosen for examination using this technique contained 4-methoxyamphetamine, an hallucinogenic amphetamine that has been encountered frequently in South Australia. Compounds found in the PMA preparation included 4-methoxyphenol, 4-methoxybenzaldehyde, 4-methoxyphenyl-2-propanone, 4-methoxyphenyl-2-propanol, 4-methoxyphenyl-propene, and (tentatively) 4-methyl-5-(4'-methoxyphenyl) pyrimidine. The presence of these compounds suggests that the active drug was prepared from 4-methoxybenzaldehyde via 4-methoxyphenyl-2-propanone using a Leuckardt reductive amination. In this instance, SPME was found to be a simple, rapid, and non-destructive recovery technique that gave results complementary to those provided by conventional liquid-liquid extraction. There is an indication that SPME might find application in profiling of illicit drugs.  相似文献   
998.
Allele distributions for 13 tetrameric short tandem repeat (STR) loci, CSF1PO, FGA, TH01, TPOX, VWA, D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51, and D21S11, were determined in African American, United States Caucasian, Hispanic, Bahamian, Jamaican, and Trinidadian sample populations. There was little evidence for departures from Hardy-Weinberg expectations (HWE) in any of the populations. Based on the exact test, the loci that departed significantly from HWE are: D21S11 (p = 0.010, Bahamians); CSF1PO (p = 0.014, Trinidadians); TPOX (p = 0.011, Jamaicans and p = 0.035, U.S. Caucasians); and D16S539 (p = 0.043, Bahamians). After employing the Bonferroni correction for the number of loci analyzed (i.e., 13 loci per database), these observations are not likely to be significant. There is little evidence for association of alleles between the loci in these databases. The allelic frequency data are similar to other comparable data within the same major population group.  相似文献   
999.
A validation study was conducted to demonstrate that deoxyribonucleic acid (DNA) could be successfully extracted from human nail material and analyzed using short tandem repeat (STR) profiling and/or mitochondrial DNA (mtDNA) sequencing. This study involved the development of a DNA extraction protocol that includes a cleaning procedure designed to remove external contaminants (e.g., biological, chemical). This protocol was used to test human nail material that had been soaked in whole blood from a second donor and coated with gold-palladium to simulate scanning electron microscopic analysis. The results showed no indication of a mixture and were consistent with that of the nail donor. Fresh human nail material usually yielded both STR profiles and mtDNA sequence information; however, aged human nail material (approximately eight years old) yielded only mtDNA sequence information. Upon completion of the validation study, the extraction protocol was used for the analysis of a torn fingernail fragment recovered from the scene of a violent homicide in 1983. A partial STR profile and mtDNA sequence information indicated that the fingernail fragment was excluded as originating from the suspect and was, in fact, consistent with originating from one of the victims.  相似文献   
1000.
Chorionic villus sampling (CVS), prior to pregnancy termination (pre-termination CVS), is suggested as a tool for forensic paternity testing. Unlike the abortion material, which consists of ruptured tissues of fetal and maternal origin, extra-embryonic membranes obtained through CVS can provide an uncontaminated source of fetal tissue for genotyping. We discuss the possibility of confined placental mosaicism (CPM) and its implications on the polymerase chain reaction (PCR) based analyses of short tandem repeats (STRs) and the D1S80 loci.  相似文献   
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