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181.
182.
Jonathan Liu John Decatur Gloria Proni Elise Champeil 《Forensic science international》2010,194(1-3):103-107
Identification of 3,4-methylenedioxy-N-methylamphetamine (MDMA, ecstasy) in five cases of intoxication using nuclear magnetic resonance (NMR) spectroscopy of human urine is reported. A new water suppression technique PURGE (Presaturation Utilizing Relaxation Gradients and Echoes) was used. A calibration curve was obtained using spiked samples. The method gave a linear response (correlation coefficient of 0.992) over the range 0.01–1 mg/mL. Subsequently, quantitation of the amount of MDMA present in the samples was performed. The benefit and reliability of NMR investigations of human urine for cases of intoxication with MDMA are discussed. 相似文献
183.
A gas chromatography–mass spectrometry (GC–MS) method was developed and validated for the simultaneous qualification and quantification of methamphetamine (MA), amphetamine (AP), 3,4-methylenedioxy-N-methylamphetamine (MDMA), 3,4-methylenedioxy-N-amphetamine (MDA), ketamine (KET) and norketamine (NKT) in fingernails. Fingernail samples (20 mg) were washed with distilled water and methanol, digested with 1.0 M sodium hydroxide at 95 °C for 30 min, and then extracted with ethyl acetate. Extract solutions were evaporated to dryness, derivatized using heptafluorobutyric anhydride (HFBA) at 60 °C for 30 min, and analyzed by GC–MS. The linear ranges were 0.1–20.0 ng/mg for AP, MDMA and NKT, 0.2–20.0 ng/mg for MA and MDA, and 0.4–20.0 ng/mg for KET, with the coefficients of determination (r2 ≥ 0.9989). The intra- and inter-day precisions were within 7.1% and 10.6%, respectively. The intra- and inter-day accuracies were ?10.9% to 0.8% and ?4.3% to 4.5%, respectively. The limits of detections (LODs) and the limits of quantifications (LOQs) for each analyte were lower than 0.094 ng/mg and 0.314 ng/mg, respectively. The recoveries were in the range of 72.3–94.9%. The average fingernail growth rates of two subjects for three years and six subjects for two months were 3.12 mm/month and 3.16 mm/month, respectively. The method proved to be suitable also for the simultaneous detection and quantification of MA, MDMA, KET and their metabolites in fingernails. 相似文献
184.
Hwan Young Lee Ph.D. Na Young Kim M.S. Myung Jin Park M.S. Jeong Eun Sim B.S. Woo Ick Yang Ph.D. Kyoung‐Jin Shin Ph.D. 《Journal of forensic sciences》2010,55(6):1422-1429
Abstract: The identification of missing casualties of the Korean War (1950–1953) has been performed using mitochondrial DNA (mtDNA) profiles, but recent advances in DNA extraction techniques and approaches using smaller amplicons have significantly increased the possibility of obtaining DNA profiles from highly degraded skeletal remains. Therefore, 21 skeletal remains of Korean War victims and 24 samples from biological relatives of the supposed victims were selected based on circumstantial evidence and/or mtDNA‐matching results and were analyzed to confirm the alleged relationship. Cumulative likelihood ratios were obtained from autosomal short tandem repeat, Y‐chromosomal STR, and mtDNA‐genotyping results, and mainly confirmed the alleged relationship with values over 105. The present analysis emphasizes the value of mini‐ and Y‐STR systems as well as an efficient DNA extraction method in DNA testing for the identification of old skeletal remains. 相似文献
185.
Hwan Young Lee Myung Jin Park Na Young Kim Jeong Eun Sim Woo Ick Yang Kyoung-Jin Shin 《Forensic Science International: Genetics Supplement Series》2010,4(5):275-280
The recovery of DNA data from old skeletal remains is often difficult due to degraded and very low yield of extracted DNA and the presence of PCR inhibitors. Herein, we compared several silica-based DNA extraction methods from artificially degraded DNA, DNA with PCR inhibitors and DNA from old skeletal remains using quantitative real-time PCR. We present a modified large-scale silica-based extraction combined with complete demineralization, that enables maximum DNA recovery and efficient elimination of PCR inhibitors. This is performed with high concentration of EDTA solution for demineralization of bone powder followed by QIAamp® spin columns and buffers from the QIAquick® PCR purification kit. We have successfully used this modified technique to perform STR analysis for 55-year-old skeletal remains. The results of this study will contribute to solve the forensic cases dealing with skeletal remains. 相似文献
186.
Comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (GC x GC-TOFMS) for drug screening and confirmation 总被引:1,自引:0,他引:1
Comprehensive two-dimensional gas chromatography (GC x GC) is applied to analysis of drug standard mixtures containing 78 drugs of interest in forensic samples. For this study, underivatised drugs were employed. While several of the drugs were not detected at the low concentrations employed in the samples, most could be satisfactorily assigned their first and second dimension retentions in the GC x GC retention plane. For this study, time-of-flight mass spectrometry (TOFMS) detection was used. The enhanced separation possible in GC x GC is demonstrated, and typical linearity and apparatus precision are shown for tramadol, diazepam, olanzapine and desipramine using selected qualifier ions. Mass spectral library search quality for the detection of drugs in a selection of authentic forensic cases, along with retention position in the 2D retention plane, is used to support positive identification of the presence of the drugs. The analysis of 'difficult' drugs paracetamol and phenytoin is shown to produce anomalous chromatographic peak shape in the 2D plane, whereas most drugs gave acceptable peak shapes. The GC x GC technique was applied to screening drugs in forensic samples, with either flame ionisation (FID) or TOFMS detection, and compared favourably with conventional single column GC-MS analysis when tested for diazepam in an authentic forensic study. 相似文献
187.
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189.
Adolescent nutritional and psychological patterns and risk for the development of an eating disorder
Gloria R. Leon Ph.D. Professor Director of Clinical Psychology Cheryl L. Perry Ph.D. Associate Professor Director of Community Health Education Carolyn Mangelsdorf M. A. Clinical psychology graduate student Grethe J. Tell D. Sc. M. Ph. Associate professor 《Journal of youth and adolescence》1988,18(3):273-282
A group of 256 female and 248 male adolescent students were assessed regarding nutritional practices and psychological attitudes associated with the development of eating disorders. While the majority showed adequate nutritional practices, there was a high prevalence of dieting and the consumption of low-calorie foods among the girls. For boys, there was no relationship between a strong desire for thinness and restriction of foods high in calories; boys tended to report that hunger and positive affective states were related to overeating. A risk factor conception of nutritional and psychological precursors to the later development of an eating disorder was discussed.This research was supported in part by a Biomedical Research Support Grant to Dr. Cheryl Perry. 相似文献
190.
The mandible is the largest and hardest facial bone and retains its shape better than other bones in the forensic and physical anthropologic field. The mandible can be used to distinguish among ethnic groups and between sexes. We examined the morphological characteristics of the mandibles of 102 Koreans of either sex. Of 13 nonmetric items of the mandible, the characteristic that best allowed the sexes to be distinguished was the contour of the lower border of the mandible: rocker-shaped mandibles predominated in males (68.1%), whereas most females (84.6%) exhibited a straight mandible. In addition, the mental region was shaped differently between the sexes: the shape of the chin in most males was generally bilobate or square (91.7%), whereas the chin in females was either square (45.5%) or pointed (54.5%). In this study, the positive predict values of male and female were 92.5% and 73.7%, respectively. Therefore, the nonmetric method used to analyze the mandible in this study can be used for sex discrimination. 相似文献