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911.
A 4-year-old child with chickenpox infection for 5 days prior to death complained of swelling and pain in his right leg that required medical assistance in the emergency department. Radiologic study was normal, and analgesic and bandage of the leg were prescribed. Some hours later, he presented cyanosis, dizziness, and vomiting and collapsed. A complete forensic autopsy was performed 12 hours after death. External examination of the body showed numerous crusty varicella skin lesions, especially over the trunk, and swelling and reddening of his right leg. The brain was swollen, with cerebellar herniation, and both adrenal glands were hemorrhagic.Microscopically, neutrophilic infiltration and muscle fiber necrosis were observed in soft tissues of his right leg, and fibrin microthrombus were numerous in capillaries of the plexus choroideus, larynx, lungs, and adrenals. Bacterial emboli were present in most of the tissues. Microbiologic cultures of blood and cerebrospinal fluid showed group A beta-hemolytic streptococcus (Streptococcus pyogenes). Death was attributed to fulminant streptococcal toxic shock syndrome, with necrotizing fasciitis as a complication of varicella.  相似文献   
912.
Nowadays, more and more paternity cases are carried out investigating only child and putative father, mostly for economical or private reasons. Usually, reliable results can be obtained and the putative father can be included or ruled out with a high certainty. Considerable problems might arise when a relative of the biological father is investigated as being the putative father. In this study, we investigated 164 persons from 27 families creating artificial deficiency cases using the AmpFlSTRIdentifiler kit, which amplifies 15 STRs simultaneously. We analyzed 93 child/biological father pairs and the corresponding uncles, respectively the brothers of the biological fathers. The average paternity probability for the biological father was 99.9699% (paternity index (PI): 3321.26); only in three cases the results were under 99.9%. In five out of 125 child/uncle pairs no STR mismatches were found and paternity probabilities between 99.9726% (PI 3652) and 99.9970% (PI 33,545) were calculated. The average number of excluding loci was 3.4, but in 31.2% of the cases only zero, one or two mismatches were found. When both putative fathers were genetically typed, the biological father usually had a statistically higher paternity probability. Nevertheless, the differences between probabilities for father and uncle were only small. These results show that a reliable investigation of deficiency cases (i.e. child and putative father) seems to be more difficult than generally assumed. Especially in cases with an unknown familiar background and/or when investigating foreigners for immigration purposes, the laboratory expert should include the mother, increase the number of investigated loci or include a second method such as RFLP-analysis, some serological systems or typing of X-chromosome specific STRs to further ascertain the results.  相似文献   
913.
Haplotype data were obtained from a sample of 777 unrelated male individuals from Antioquia Department (Colombia), for eight Y-chromosome STRs (DYS19, DYS385, DYS389 I, DYS389 II, DYS390, DYS391, DYS392 and DYS393). A total of 442 different haplotypes were identified of which 334 were represented only once in the database and the most frequent haplotype was found in 32 individuals. A high haplotype diversity was found (99.45%). Genetic distances were calculated using previously published haplotype data and the lowest values were found for the comparisons with samples of lberian origin.  相似文献   
914.
Automated comparison of firearm bullets   总被引:4,自引:0,他引:4  
Fired bullets bear striation marks that can be thought of as a "fingerprint" left by the firearm. This new comparison approach is based on an automated extraction of a "signature" encompassing the relevant marks from an image. To this end, multiple pictures of the bullet are recorded first by using different illumination patterns, and a high quality image is generated by means of fusion techniques. After a preprocessing, the image intensities are filtered along the striations direction, yielding a compact representation of the marks. A non-linear filter selects the striae of interest. The actual comparison takes place by cross-correlating the signatures obtained this way. Finally, an assessment strategy is proposed to objectively evaluate the performance of the system. As demonstrated with an image database of real bullets, the proposed approach outperforms a state-of-the-art commercial system.  相似文献   
915.
Nuclear and mitochondrial DNA quantification of various forensic materials   总被引:1,自引:0,他引:1  
Due to the different types and quality of forensic evidence materials, their DNA content can vary substantially, and particularly low quantities can impact the results in an identification analysis. In this study, the quantity of mitochondrial and nuclear DNA was determined in a variety of materials using a previously described real-time PCR method. DNA quantification in the roots and distal sections of plucked and shed head hairs revealed large variations in DNA content particularly between the root and the shaft of plucked hairs. Also large intra- and inter-individual variations were found among hairs. In addition, DNA content was estimated in samples collected from fingerprints and accessories. The quantification of DNA on various items also displayed large variations, with some materials containing large amounts of nuclear DNA while no detectable nuclear DNA and only limited amounts of mitochondrial DNA were seen in others. Using this sensitive real-time PCR quantification assay, a better understanding was obtained regarding DNA content and variation in commonly analysed forensic evidence materials and this may guide the forensic scientist as to the best molecular biology approach for analysing various forensic evidence materials.  相似文献   
916.
The forensic value of Y-STR markers in Guiné-Bissau was accessed by typing of 215 males. Allele and haplotype frequencies, determined for loci DYS19, DYS389-I, DYS389-II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438, DYS439 and the duplicated locus DYS385, are within the limits of variation found in other populations south of the Sahara. The level of discrimination achieved is Guineans is higher than for European or other African populations with comparable data. The haplotype diversity of 0.9995 is reduced to 0.9981 when the minimal haplotype is considered thus revealing the importance of increasing the number of typed loci.  相似文献   
917.
This article analyses the repercussions that the Preimplantational Genetic Diagnosis (PGD) has in the bioethical as well as legal fields in relation with the so-called "reproductive freedom" of the couple. Besides analysing the legal situation of this technique in Spain as well as other surrounding States, the article studies the problems associated with some scenarios of PGD, such as the use in the selection of sex, for therapeutic purposes for third parties, in relation with diseases of a possible late onset, multifactorial or of a variable phenotype expression and for the selection of embryos affected by a disease or disability. All are based on real clinical cases.  相似文献   
918.
The aim of this study was to examine the roles of sense of belonging and gender in the academic outcomes of urban, Latino adolescents. It was expected that sense of belonging would play a different role in males' and females' academic adjustment. Participants (N = 143) included mostly Mexican and Puerto Rican seniors from a large, urban high school. The academic outcomes assessed were grade point average, absenteeism, motivation, effort, and educational aspirations and expectations. As hypothesized, females consistently had more positive academic outcomes than males. Sense of school belonging significantly predicted academic outcomes, including academic motivation, effort, and absenteeism. Regression analyses did not show that gender explained differences in the relationship between sense of belonging and academic outcomes. Implications and future directions for research on urban Latino males and females are discussed.  相似文献   
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920.
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