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931.
Reference material was synthesised for 21 substances that are frequently present as synthetic impurities, i.e. by-products, in illicitly produced amphetamine. Each of these substances is a typical by-product for at least one of the three approaches most often used to synthesise amphetamine, namely, the Leuckart, the reductive amination of benzyl methyl ketone, and the nitrostyrene routes. A large body of data on the substances was recorded, including the following: mass spectra, ultraviolet spectra, Fourier transform infrared spectra, infrared spectra in gas phase, and 1H NMR and 13C NMR spectra.  相似文献   
932.
The present study focused on the stability of 22 amphetamine impurities dissolved in six organic solvents: isooctane, toluene, ethanol, dichloromethane, ethyl acetate, and diethyl ether. The aim was to find the most inert, and thereby most suitable, solvent for amphetamine profiling. Mixtures of the impurities were prepared in the different solvents, and changes in the concentrations of the individual compounds over-time were monitored by gas chromatographic analysis after 0, 4, 12, 24, 48, and 96 h. Isooctane and toluene provided the most inert conditions, although, a few of the impurities were insufficiently stable in these two solvents. The present experiments were performed as a part of the development of a harmonized method for profiling of amphetamine. The results can be used to support the choice of organic solvents for sample preparation. They also provide information about the stability of the impurities that are found in profiles of illicit amphetamine. This is essential due to the fact, that unstable compounds can have a negative influence on the comparison of profiles.  相似文献   
933.
934.
A highly sensitive screening method based on high performance liquid chromatography atmospheric pressure ionization mass spectrometry (HPLC-API-MS) has been developed for the analysis of 21 nitroaromatic, nitramine and nitrate ester explosives, which include the explosives most commonly encountered in forensic science. Two atmospheric pressure ionization (API) methods, atmospheric pressure chemical ionization (APCI) and electrospray ionization (ESI), and various experimental conditions have been applied to allow for the detection of all 21 explosive compounds. The limit of detection (LOD) in the full-scan mode has been found to be 0.012-1.2 ng on column for the screening of most explosives investigated. For nitrobenzene, an LOD of 10 ng was found with the APCI method in the negative mode. Although the detection of nitrobenzene, 2-, 3-, and 4-nitrotoluene is hindered by the difficult ionization of these compounds, we have found that by forming an adduct with glycine, LOD values in the range of 3-16 ng on column can be achieved. Compared with previous screening methods with thermospray ionization, the API method has distinct advantages, including simplicity and stability of the method applied, an extended screening range and a low detection limit for the explosives studied.  相似文献   
935.
The FearID research project is aimed at the individualisation of earprints for the purpose of forensic research. The study presented here was carried out within the framework of this project. It intends to combine a review of what is known from literature on the classification and individualisation of earprints with results from a preliminary study of earprints. Possibilities for, and limitations to, the use of earprints in forensic investigation are addressed. Differences between eliminating a suspect, placing a suspect at a crime scene, and linking crimes by prints left at different scenes are considered.  相似文献   
936.
van Praag HM 《危机》2002,23(2):77-82
Over the past decades the rate of completed suicide has remained quite stable, whereas that of suicide attempts seems to have increased (to the extent it has been studied in defined regions). These are puzzling observations, since depression is the major suicide precursor and and since antidepressants have been increasingly used over the years in the treatment of depression. These observations have not attracted sufficient attention, possibly because they do not accord with consensus opinions about depression treatment in psychiatry today. This paper discusses a number of possible explanations that not only deserve, but are definitely in need of systematic investigation.  相似文献   
937.
The authors report on three cases of myiasis which rarely occurs in the civilized world. Poor social conditions, old age, alcoholism, diabetes and vascular occlusive disease were predisposing co-factors. All three victims showed large necrotizing skin ulcerations, but in no case a generalized infection had developed. Therefore the probable benefit from the maggot infestation concerning these ulcerating skin lesions is discussed. For centuries clinicians have observed that maggots provide debridement of necrotic wounds particularly in Military Medicine. With the advent of antibiotics their therapeutic use declined. Recently "biosurgery" (syn. maggot or larval therapy) again became a promising tool for therapy of infected, necrotizing skin-ulcerations. Besides wound debridement marked anti-microbial activity and secretion of proteolytic enzymes could be detected. Maggot debridement is an valuable and cost-effective treatment option for patients with nonhealing wounds.  相似文献   
938.
The use of a QIAamp DNA Stool Mini Kit (QIAGEN) for extracting human nuclear DNA from feces samples is reported. This method employs a stool lysis buffer and a unique matrix (InhibitEX tablet) to remove PCR inhibitory substances specific to feces samples. DNA extracted from various amounts of stool and from stool samples exposed to different environmental impacts was successfully amplified and typed using the Profiler Plus Amplification Kit and ABI PRISM 310 Genetic Analyser.  相似文献   
939.
940.
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