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971.
A new method for diatom detection is described. It includes an ultrasonic irradiation procedure with the use of a tissue solubilizer. The method is easy to carry out and is less time-consuming than previous techniques. 相似文献
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979.
Hair analysis for fenfluramine and norfenfluramine as biomarkers for N-nitrosofenfluramine ingestion
In this paper, a high performance liquid chromatographic method with fluorescence detection (HPLC-FL) for the determination of fenfluramine (Fen) and norfenfluramine (Norf) in human hair as biomarker metabolites of N-nitrosofenfluramine (N-Fen) is described. Washed and cut hair segments were extracted by ultrasonication for 1h at room temperature in methanol. The extract was evaporated and applied for derivatization with the fluorescent reagent 4-(4,5-diphenyl-1H-imidazol-2-yl)benzoyl chloride (DIB-Cl). An HPLC-FL analysis was performed using an ODS column with mobile phase composition of acetonitrile and water (65:35, v/v) and monitored at 430 nm (excitation 325 nm). The method was sensitive with detection limits of 36 and 16 pg/mg hair for Fen and Norf, respectively. The linearity was assessed in the range 0.036-144 ng/mg for Fen and 0.016-127 ng/mg for Norf with correlation coefficients larger than 0.999. The method was successfully used for the segmental determination of Fen and Norf in hair samples obtained from hospitalized patients diagnosed with hepatotoxicity and suspected to ingest N-Fen. Both Fen and Norf could be detected in these patients' hair samples in the ranges 43-1389 pg/mg for Fen and 18-680 pg/mg for Norf and the results showed that the patients might ingest N-Fen for a period of not less than 5 months. As well, the method was applied for the determination of Fen and Norf in rats that possess pigmented and non-pigmented hair after an intraperitoneal administration of Fen. Both compounds were determined in black as well as in white hair. 相似文献
980.
Clinical forensic medicine and its main fields of activity from the foundation of the German Society of Legal Medicine until today 总被引:2,自引:0,他引:2
Pollak S 《Forensic science international》2004,144(2-3):269-283
The fields mainly covered by clinical forensic medicine are subject to time-related changes which are described on the basis of the German literature of the 20th century. Some fields of forensic sexual medicine (diagnosis of virginity, proof of criminal abortion, potentia coeundi, potentia generandi, potentia concipiendi) have become less important in the daily work of medicolegal institutes, whereas victims of rape and sexual abuse continue to form a major part of the forensic examination material in the German-speaking countries. The evaluation of suspected physical child abuse has grown in importance since the 60s, and it is essentially the merit of Elisabeth Trube-Becker that this problem is now dealt with also in scientific medicine. More recently, medicolegal experts are increasingly confronted with further groups of persons: victims of domestic violence, abused/neglected seniors, refugees from countries where torture is used. A new special field, which established itself only in the 90s, is the estimation of age with regard to the criminal responsibility of suspects who have no identity papers or pretend to have none. A phenomenon frequently observed in the last two decades is the non-accidental self-infliction of injuries. Whereas in the first half of the 20th century the motive for self-mutilation was typically to evade military service, this category of injury was later mainly seen in the context of insurance fraud; more recently most forensically relevant self-inflicted injuries refer to simulated offenses (fictitious sexual offenses and robbery, attacks allegedly having a political background). One of the traditional fields of clinical forensic medicine continues to be the evaluation of victims and suspects following bodily harm and attempted homicides. In the field of civil law medicolegal experts are particularly often concerned with controversial consequences of traffic accidents (e.g. alleged whiplash injuries after rear-end collisions at low velocities). 相似文献