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971.
Value of fetal autopsy after medical termination of pregnancy   总被引:2,自引:0,他引:2  
We carried out a retrospective study of 352 medical terminations of pregnancy (MTP) carried out in a large French administrative region over two consecutive years. We analysed the indications for MTP and then compared the prenatal ultrasound diagnosis with fetal autopsy findings in order to demonstrate the value of pathological examination of the fetus in prenatal diagnosis and genetic counselling as well as the need to check by autopsy the quality of ultrasound screening. Preliminary analysis of the indication for these MTP showed that in 69.9% ultrasound screening had been carried out, revealing mainly brain abnormalities (22.2%) and heart defects generally associated with chromosomal abnormalities (32.1%). Prenatal findings were in agreement with autopsy results, showing no false-positive prenatal diagnoses. However, in 7.9% of cases in which brain abnormalities were detected, confirmation was not possible at autopsy because of tissue autolysis, showing the need for optimal conditions of expulsion. In 35.8% of cases, confirmation of the diagnosis by autopsy was not useful for management but still added to medical knowledge and demonstrated to the mother the reality of the defects. In 50.9%, the autopsy findings were decisive for genetic counselling.  相似文献   
972.
973.
In this study, we analyzed allelic sequences of 10 novel Y-specific STR loci, DYS454, DYS510, DYS513, DYS520, DYS542, DYS544, DYS552, DYS561, DYS587 and DYS593, surveyed the distribution of haplotypes in a Chinese Han population. Extracted DNA was amplified with PCR, followed by a horizontal non-denaturing polyacrylamide gel electrophoresis with discontinuous buffer system. Purified alleles were sequenced on DNA sequencer (ABI Model 377) to verify the number of motif repeats. The number of alleles observed at each locus ranged from 3 to 8, yielding 102 haplotypes in 103 unrelated males samples. The allele diversity values for each locus ranged from 0.2099 (DYS544) to 0.7523 (DYS552). The haplotype diversity using all these loci was 0.9998. Our study revealed that they were valuable Y-specific markers for forensic applications.  相似文献   
974.
In the Oslo and Copenhagen areas, 77 instances of blunt force homicides were committed from 1985-1994, accounting for 18% of all homicides in that 10-year period. Fifty-four (70%) of the victims were male, often killed by an acquaintance during a fight. Almost 70% of the female victims were killed in their own home, whereas that was the case for only 30% of the male victims. The majority of the victims (of both sexes) had been hit in more than 1 region of the body. A female offender was encountered in 4 instances; none of their victims were children. Of the 3 children in the blunt force victim group, 2 were battered children. Many of the victims with a blood alcohol level of 0 turned out to have lived for some time after the injury.  相似文献   
975.
Some previous research indicates that confidence affects the accuracy of probabilistic clinical ratings of risk for violence among civil psychiatric inpatients. The current study investigated the impact of confidence on actuarial and structured professional risk assessments, in a forensic psychiatric population, using community violence as the outcome criteria. Raters completed the HCR-20 violence risk assessment scheme for a sample of 100 forensic psychiatric patients. Results showed that accuracy of both actuarial judgments (HCR-20 total scores) and structured professional judgments (of low, moderate, and high risk) were substantially more accurate when raters were more confident about their judgments. Findings suggest that confidence of ratings should be studied as a potentially important mediator of structured professional and actuarial risk judgments.  相似文献   
976.
STR genotyping and mtDNA sequencing of latent fingerprint on paper   总被引:1,自引:0,他引:1  
A systematic study was conducted to investigate whether DNA can be successfully extracted from latent fingerprints deposited on ordinary paper and analysed using short tandem repeat profiling and mitochondrial DNA sequencing. In order to evaluate the performance of latent fingerprint analysis in a criminal case, experiments with varying conditions were carried out to improve our understanding of low copy number (LCN) DNA typing. After optimising the extraction methods to achieve increased sensitivity, the examination of touched paper can routinely yield the STR profile of the individual who has touched it. A fingerprint can therefore be considered as a potential source of DNA for genetic identification. Nevertheless, the findings of our "after enhancement experiment" (using chemically or physically pre-treated fingerprints), and our "mixture experiment" (using fingerprints from three to four people on the same sheet of paper) help to define the limitations of the low copy number PCR technique in forensic casework.  相似文献   
977.
Sexual differences in the human skeleton have been well studied in many populations. Odontometric analysis of the human sexual variation has been less investigated and mostly derived from the dentition of extinct populations. Turkey is situated in a unique location where populations from different regions mixed with each other and created a rich gene pool. One might anticipate that modern Turkish population is composed of genes from the Balkans, Caucasus, Middle East, Iran and further as well as from ancient Romans, Byzantines, Arabs and Asiatic Turks. It is clear that contemporary Turks are a mixture of these extant and extinct people and ideal to consider it a representative study population. The purpose of this study is to analyze dental dimensions and sexual variation in living Turks and develop forensic techniques to identify human remains from the teeth when any other technique is not available or not reliable. The study is composed of Ankara University dental students (50 male and 50 female casts, average age of 21 years). Bucco-lingual breadths from 14 teeth (I1 through M2 of the maxilla and mandible) are taken from the left side and analyzed using the discriminant function statistics. An intraobserver error test did not indicate any statistically significant difference between any two measurements. Results of the study revealed that males exceeded females significantly (P<0.001) in dimensions. Coefficient of variation was most obvious in I1s and I2s of both jaws in both sexes. Stepwise discriminant function statistics suggested that upper C, and lower C and M2 are the most contributory teeth to the function. Additional formulae were calculated for situation in which only one or a fragmented jaw is available for identification. Overall accuracy of sex diagnosis ranged from 73 to 77%. In conclusion this research supports earlier studies that sexual dimorphism is population specific. While dental difference between the sexes in several human populations has been found highly dimorphic, it was not found so in Turks and accuracy of classification remained low at about 77%. The difficulty or the lack of dimorphism comes from male subjects.  相似文献   
978.
The recreational use of amphetamine derivatives has become increasingly popular in our country in past recent years. Their use is especially common among young people participating in dance parties known as "raves." As a direct consequence of their increased use, the number of fatal cases in which these compounds have been involved have increased dramatically since the second half of the last decade. In our laboratory, we have registered 25 cases related to amphetamine derivatives use since 1996. Three of them were deeply studied and the results obtained are presented in this paper. This information may be useful for the interpretation of the results obtained in toxicological analysis in the cases in which death may be attributed to MDMA use.  相似文献   
979.
Bite mark identification is based on the individuality of a dentition, which is used to match a bite mark to a suspected perpetrator. This matching is based on a tooth-by-tooth and arch-to-arch comparison utilising parameters of size, shape and alignment. The most common method used to analyse bite mark are carried out in 2D space. That means that the 3D information is preserved only two dimensionally with distortions. This paper presents a new 3D documentation, analysis and visualisation approach based on forensic 3D/CAD supported photogrammetry (FPHG) and the use of a 3D surface scanner. Our photogrammetric approach and the used visualisation method is, to the best to our knowledge, the first 3D approach for bite mark analysis in an actual case. The documentation has no distortion artifacts as can be found with standard photography. All the data are documented with a metric 3D measurement, orientation and subsequent analysis in 3D space. Beside the metrical analysis between bite mark and cast, it is possible using our method to utilise the topographical 3D feature of each individual tooth. This means that the 3D features of the biting surfaces and edges of each teeth are respected which is--as shown in our case--very important especially in the front teeth which have the first contact to the skin. Based upon the 3D detailed representation of the cast with the 3D topographic characteristics of the teeth, the interaction with the 3D documented skin can be visualised and analysed on the computer screen.  相似文献   
980.
A criminal case was directed to a multidisciplinary forensic team for identification, concerning a victim whose head, having two gunshot wounds, had been separated by a sharp instrument and was recovered 6 months later. The purpose of this research was to determine the sex and age of the victim for human identification. Primarily, macroscopic examination of the skull, tooth, and DNA analysis was conducted for sex determination. A rough assessment of age was made from the skull based on anthropological findings, however a more definitive result of age estimation was determined utilizing dental morphology. The dental data showed an age range of 32-37 from the mineral examination and the formulation of microscopic measurements. The results obtained from the skull and dental analysis matched with the physical characteristics of the victim's body, the known personal data of this person, and with the superposition of the photos gathered by a formal request. Besides, the result of DNA profiling of the victim showed male gender and direct relationship with the victim's presumed wife and daughter. Generally, research on human identification consists of sex and age determination. The sex characteristics can be precisely proved from DNA tests. However, age can be estimated by skeletal, and dental analysis. In this case the performed sex and age analysis lead the research to the selective matching of the missing person's identity.  相似文献   
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