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181.
A simple procedure based on a common silica gel column chromatography for the isolation of Delta9-tetrahydrocannabinolic acid A (Delta9-THCA-A) from hemp in a multi-milligram scale is presented. Further, the decarboxylation reaction of Delta9-THCA-A to the toxicologically active Delta9-tetrahydrocannabinol (Delta9-THC) at different analytical and under-smoking conditions is investigated. Maximal conversion in an optimised analytical equipment yields about 70% Delta9-THC. In the simulation of the smoking process, only about 30 % of the spiked substance could be recovered as Delta9-THC.  相似文献   
182.
The rapid further development of computed tomography (CT) and magnetic resonance imaging (MRI) induced the idea to use these techniques for postmortem documentation of forensic findings. Until now, only a few institutes of forensic medicine have acquired experience in postmortem cross-sectional imaging. Protocols, image interpretation and visualization have to be adapted to the postmortem conditions. Especially, postmortem alterations, such as putrefaction and livores, different temperature of the corpse and the loss of the circulation are a challenge for the imaging process and interpretation. Advantages of postmortem imaging are the higher exposure and resolution available in CT when there is no concern for biologic effects of ionizing radiation, and the lack of cardiac motion artifacts during scanning. CT and MRI may become useful tools for postmortem documentation in forensic medicine. In Bern, 80 human corpses underwent postmortem imaging by CT and MRI prior to traditional autopsy until the month of August 2003. Here, we describe the imaging appearance of postmortem alterations--internal livores, putrefaction, postmortem clotting--and distinguish them from the forensic findings of the heart, such as calcification, endocarditis, myocardial infarction, myocardial scarring, injury and other morphological alterations.  相似文献   
183.
A new retrieval system for a 3D facial image database was designed and its reliability was experimentally examined. This system has two steps, firstly to automatically adjust the orientation of all 3D facial images in a database to that of the 2D facial image of a target person, and then to identify the facial image of the target person from the adjusted 3D facial images in the database using a graph-matching method. From the experimental study [M. Yoshino, K. Imaizumi, T. Tanijiri, J.G. Clement, Automatic adjustment of facial orientation in 3D face image database, Jpn. J. Sci. Tech. Iden. 8 (2003) 41-47], it is concluded that the software developed for the first step will be applicable to the automatic adjustment of facial orientation in the 3D facial image database. In 28 out of 110 sets (25.5%), the 3D image of the target person was chosen as the best match (from a database of 132 3D facial images) according to the similarity of the facial image characteristics based on the graph matching. The 3D facial image of the target person was ranked in the top of 10 of the database in 75 out of 110 sets (68.2%). These results suggest that this system is inadequate for the identification level, but may be feasible for screening method in a small database. It will be necessary to further pursue the possibility of realization of a facial image retrieval system for a large database such as suspects' facial images in future.  相似文献   
184.
Spontaneous pneumomediastinum commonly occurs in healthy young men or parturient women in whom an increased intra-alveolar pressure (Valsalva maneuver, asthma, cough, emesis) leads to the rupture of the marginal pulmonary alveoli. The air ascends along the bronchi to the mediastinum and the subcutaneous space of the neck, causing cervico-fascial subcutaneous emphysema in 70-90% of cases. Ninety-five forensic cases, including five cases of hanging, were examined using postmortem multi-slice computed tomography (MSCT) and magnetic resonance imaging (MRI) prior to autopsy until December 2003. This paper describes the findings of pneumomediastinum and cervical emphysema in three of five cases of hanging. The mechanism of its formation is discussed based on these results and a review of the literature. In conclusion, when putrefaction gas can be excluded the findings of pneumomediastinum and cervical soft tissue emphysema serve as evidence of vitality of a hanged person. Postmortem cross-sectional imaging is considered a useful visualization tool for emphysema, with a great potential for examination and documentation.  相似文献   
185.
Steamer accidents, through contact with the bucket wheel, are very seldom today. No publication of such a kind of fatal accident could be found in literature. We present the case of a fatal steamer accident, in which the findings of a blunt traumatization of a person by the ship was completely documented by post-mortem combined multi-slice computed tomography (MSCT) and magnetic resonance imaging (MRI) examinations. A rupture of the aorta was detected using both radiological methods without use of radiopaque material. Radiological examination revealed a comminuted fracture of the thorax vertebrae at the same level as the aortic rupture. Injuries of the soft tissues of the back, caused by the bucket wheel of the steamer, were also diagnosed. In addition to the signs of blunt force trauma the findings of drowning such as an over inflation of the lungs, fluid in the stomach and duodenum were revealed. Furthermore, algological analysis detected diatoms in the lung tissue and blood from the left heart. Therefore, the cause of death was considered being a combination of fatal hemorrhage, caused by the aortic rupture, and drowning. We conclude that virtual autopsy using combined post-mortem MSCT and MRI is a useful tool for documentation, visualisation and analysis of the findings of blunt force trauma and drowning with a large potential in forensic medicine.  相似文献   
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Women who seek medical care following sexual assault are usually evaluated and treated in an emergency department (ED). Therefore, EDs can be an important source of sexual assault surveillance data. The authors compared the incidence of sexual assault presenting for emergency care in a single county during July to November of 1974 and 1991. Participants included all female sexual assault victims aged 14 and older who presented for ED evaluation. Treating physicians prospectively collected data using standardized forms. The z statistic was used to compare sexual assault incidence. There was a 60% increase in the incidence of sexual assault victims presenting for emergency care in 1991 compared to 1974, primarily due to an increase in the incidence of women presenting to the ED after rapes by known assailants. In contrast, the annual incidence of reported stranger assaults was similar in the two study years.  相似文献   
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