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A simple technique is presented for the longitudinal sectioning of hair samples without the need for any embedding medium. The technique applies to single hair samples that are placed in a groove of a particular depth and can either be scraped or cut to the desired level. Planar sections are obtained that reveal the internal structure of the sample and are ideal for the application of surface analytical techniques for the study of internal transverse and longitudinal distributions of xenobiotics. 相似文献
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Trivedi R Chattopadhyay P Kashyap VK 《The American journal of forensic medicine and pathology》2002,23(2):191-196
A new method for better recovery of DNA suitable for amplification of hypervariable loci from fragments of teeth, consisting of two steps-scraping and aspiration, and extensive decalcification-is reported. Higher yields of high molecular weight DNA were obtained from the root, pulp, and crown of all kinds of 120 teeth, irrespective of gender, age, and source of teeth. HLA DQA1, 5 poly markers (LDLR, GYPA, HBGG, D7S8, and Gc), and other 12 short tandem repeat loci (HPRTB, F13B, LPL, D13S317, D7S820, D5S818, D21S11, D18S51, FGA, D8S1179, D3S1358, and vWA) could be successfully amplified and typed from recovered DNA. 相似文献
237.
The aim of the present investigation was to reconstruct the chronological age based on the dental developmental stages of third molars evaluated on orthopantomograms. A total of 1175 orthopantomograms were assembled from patients of Caucasian origin between 16 and 22 years of age. Each third molar present was scored by two observers according to a 10-stage developmental scale. The kappa statistics measured the intra- and inter-observer reliability. The general statistical analysis was based on multiple regression analysis in order to obtain multiple regression formulas for dental age estimation based on the number of third molars present on the evaluated orthopantomogram. No regression models were statistically significant when there was only one-third molar present because of the relatively small number of orthopantomograms that fitted this criterion. A strong agreement was found between the intra- and inter-observer measurements. The statistical analysis revealed both for males and females high Pearson correlation coefficients between contralateral third molars and smaller coefficients between antimeres. The obtained multiple regression formulas are only applicable in certain specified conditions, for instance when four third molars are present the following formulas should be used in a Caucasian male "age=10.2000+0.5122UL+0.5273LL" (developmental stage of upper and lower left third molars) or in case of a female "age=13.6206+0.1933UR+0.5080LR" (developmental stage of upper and lower right third molars). This investigation revealed that the chronological age of a Caucasian individual may be estimated based on regression formulas with a S.D. of 1.52 or 1.56 years for males and females, respectively, when all four third molars are present. 相似文献
238.
Polymorphism at 15 microsatellite loci was studied in four predominant, endogamous populations of Maharashtra state in India. The studied population included Marathas, Desasth Brahmins, Chitpavan Brahmins and Dhangars; all of whom belong to Marathi speaking linguistic group of India. The distribution of the allele pattern at 13 tetranucleotide repeat and two pentanucleotide repeat of Powerplex 16 System portrays that these markers are highly polymorphic and thus, informative in human identification and understanding diversity in the addressed populations. 相似文献
239.
Although microsatellite diversity in autosomal chromosomes has been extensively described for many of the Indian populations, there is still a lacuna left on information about the genetic diversity of tribal populations. This paper reports the genetic data on the three tribal populations belonging to the Austroloid ethnic group from Orissa (Juang, Paroja and Saora). The 15 STR (D3S1358, THO1, D21S11, D18S51, PentaE, D5S818, D13S317, D7S820, D16S539, CSF1PO, PentaD, vWA, D8S1179, TPOX, FGA) polymorphism would help to accentuate the STR database for better understanding of population genetics and forensic applications. The microsatellites included in the system are found to be highly polymorphic, with the combined power of exclusion being greater than 0.999, in all the three investigated populations. 相似文献
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The purpose of this research was to examine gender and body mass, as factors linked to perceived experiences within the peer appearance culture. The sample included 215 girls and 200 boys who were either in 7th grade or 10th grade. Students provided self-reports on experiences in three domains: appearance culture among friends (appearance conversations and diet/muscle talk), peer evaluations (peer appearance pressure, appearance teasing, and vicarious peer teasing), and peer acceptance concerns (appearance-based acceptance, peer appearance comparison). The results indicated that although girls reported more appearance conversations, boys perceived more appearance pressure and teasing. Boys also admitted that they talked with friends about muscle building at a rate greater than girls talked about dieting. BMI showed distinct gender patterns. BMI was a key attribute that unified the experiences within the appearance culture for overweight girls. Among the boys, BMI was associated with differentiated experiences for underweight and overweight participants.Associate Professor in Educational Psychology at the University of Washington. She is a developmental psychologist specializing in the contributions of peers to body image and social-emotional well-being during adolescence. Research interests include body image during adolescence and gender differences.Doctoral student at the University of Washington in Human Development and Cognition. Her research focuses on the social-emotional development of adolescents, academic and appearance social comparisons, and issues related to gender and science. Research interests include body image during adolescence, gender differences, social comparison, and academic competence. 相似文献