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941.
Regular consumption of cannabis can easily be detected by examination of hair for tetrahydrocannabinol, cannabinol, and cannabidiol. Although several studies have demonstrated that after contamination with smoke or treatment with THC containing shampoos THC is not detectable, or only in small traces, the detection of 11-nor-9-carboxy-delta 9-tetrahydrocannabinol (THCCOOH) should be offered to prove the consumption and metabolisation of THC. Up to now this confirmation was only available using tandem MS techniques combined with negative chemical ionisation. A new method using a normal quadrupole GC/MS is described. The lack of expensive instruments has to be paid for by a costly and time consuming extraction and clean-up. After the sample has been digested by 2 M NaOH at 95 degrees C and the neutralised liquid has been extracted with a mixture of n-hexane and ethyl acetate the dried residue is reconstituted in acetonitrile-methanol-0.01 M sulfuric acid (49:21:30, v/v/v) and the cannabinoids separated by HPLC. Each fraction is collected over 1 min. Another extraction with n-hexane-ethyl acetate is followed by evaporation, derivatisation, and GC/MS determination. The calibration with THCCOOH spiked hair led to a LOD of 0.3 pg/mg and a LOQ of 1.1 pg/mg. 相似文献
942.
Computer-assisted facial image identification system using a 3-D physiognomic range finder 总被引:3,自引:0,他引:3
Yoshino M Matsuda H Kubota S Imaizumi K Miyasaka S 《Forensic science international》2000,109(3):225-237
This system consists of a 3-D physiognomic range finder and a computer-assisted facial image superimposition unit. The 3-D range finder is composed of a detector for measuring facial surface and its control computer. The detector has two sinusoidal grating projection devices and two CCD cameras. The computer-assisted facial image superimposition unit consists of a host computer including a proprietary software, a flat surface color display and a color image scanner for inputting 2-D facial images of a criminal. The 3-D facial shape and texture of a suspect is obtained by using the range finder. To make the comparison between the 3-D facial image and the 2-D facial image, the 3-D facial image is first reproduced on a display of the host computer from a MO disk and then the 2-D facial image is taken with the color image scanner and reproduced on the display. The 3-D facial image is exactly adjusted to match the orientation and size of the 2-D facial image under the fine framework mode, and then the fine framework mode of 3-D facial image is converted to the fine texture image. The shape and positional relationships of facial components between the 3-D and 2-D facial images are examined by the fade-out or wipe image mode. The distance between the selected two points and angle among the selected three points on the 3-D and 2-D facial images are automatically measured for the assessment of anthropometrical data between both images. For evaluating the fit between the anthropometrical points on the 3-D and 2-D facial images, the reciprocal point-to-point difference between both images is compared. 相似文献
943.
Mitchell E Krous HF Donald T Byard RW 《The American journal of forensic medicine and pathology》2000,21(4):395-400
Retrospective analysis of autopsy findings in 60 infants who had been found unexpectedly dead in their cribs or beds in South Australia from 1994 to 1998 was undertaken to determine the diagnostic usefulness of individual stages in the postmortem investigation. Positive findings occurred in 2 of 43 scene examinations (3%), 2 of 60 external examinations (3%), 2 of 11 radiologic examinations (18%), 8 of 60 internal examinations (13%), 7 of 60 histologic examinations (12%), and 3 of 58 microbiologic examinations (5%). No positive findings were detected on toxicologic screening. Not every case underwent each diagnostic step. This gave alternative diagnoses to sudden infant death syndrome (SIDS) in 15 cases (25%). This study demonstrates an increase in the percentage of cases of unexpected infant death due to causes other than SIDS; it also shows the diagnostic yield of individual stages in the postmortem evaluation of such cases. Negative findings were important in giving validity to the diagnosis in the 45 cases that were ultimately designated as SIDS. 相似文献
944.
945.
Niijima H Nagao M Nakajima M Takatori T Iwasa M Maeno Y Koyama H Isobe I 《Forensic science international》2000,112(2-3):171-178
One sarin-like and one soman-like organophosphorus agent [bis(isopropyl methyl)phosphonate, BIMP and bis(pinacolyl methyl)phosphonate, BPMP] were injected intravenously (iv) in rats. An increase in the tyrosine phosphorylation of several proteins in the cytosol fraction of the brain was observed. Activation of c-Jun N-terminal kinase (JNK) and slight activation of mitogen-activated protein kinase (MAPK) in the cytosol were also observed. The activation of these enzymes may be related to the high toxicity of these nerve agents. 相似文献
946.
Abdel-Rahman HA 《Forensic science international》2000,114(2):97-105
The increase in the use of photographs on individual identification credentials such as driving licences, credit cards, security passes and passports has led, for the purpose of criminal activities, to the falsification of genuine documents bearing photographs of the perpetrating criminal. These photographs may be used as valuable physical evidence when compared with known photographs of a suspect as they form somewhat of a signature of the suspect that is left behind on the evidence. The comparison of ID photographs requires the cooperation of two predominantly visual disciplines; forensic photography and morphological anatomy. This paper describes a photographic technique which allows accurate anatomical measurement and tracing of facial features, which allows direct physical comparison of ID document images. 相似文献
947.
A Portuguese Caucasian population of 146 unrelated individuals was studied. DNA samples were amplified by multiplex PCR for D3S1358, vWA, FGA, D8S1179, D21S11, D18S51, D5S818, D13S317 and D7S820 using the AmpFlSTR Profiler Plus PCR Amplification Kit (Perkin-Elmer). All loci met Hardy-Weinberg expectations. Forensic statistical parameters were according to those obtained by other authors. Statistical differences were observed concerning three loci when comparing the Portuguese Caucasian population and an Italian Caucasian population, although these differences mainly concern the less frequent alleles. Eighty-three paternity investigation cases were analysed. Exclusions in between three and nine loci were observed in all the 23 exclusion cases obtained. Most of the non-exclusion cases had probability of paternity > 99.9%. Two cases with an isolated genetic incompatibility between the alleged father and the child were detected, which may indicate probable mutation cases. These results demonstrate that the AmpFlSTR Profiler Plus is a suitable multiplex for paternity investigation in the Portuguese population. 相似文献
948.
To improve the possibilities to delimit the time of death after longer laytime it was examined if this is possible by immunohistochemical detection of thyroglobulin. The results show that in our examination material the colloid and the follicular cells of the thyroid glands of up to 5-day-old corpses produce a positive immunoreaction towards thyroglobulin in all cases whereas none of the corpses older than 13 days show such a reaction. This means that in case of a negative immunoreaction the time of death can be assumed to lie more than 6 days before the autopsy. The fact that a negative immunoreaction occurs consistently after 13 days leads to the conclusion that when thyroglobulin has been stained in a specimen, the death of the respective person must lie a maximum of 12 days earlier, whereby these time-limits may change in considerably different surrounding conditions. 相似文献
949.
To develop a method of detecting methadone in the human brain by immunohistochemistry, brain tissue of frontal cortex, cerebellum, hippocampus, basal ganglions and brain stem from victims of a lethal methadone overdose was examined. The staining was performed with a monoclonal anti-methadone antibody from the mouse, originally developed for immunochemichal purposes (ELISA). With the help of the DAKO((R)) Catalyzed Signal Amplification (CSA) System, a specific positive immunoreaction was obtained in the neurons of the frontal cortex and hippocampus, as compared with specimen from deaths without exposition to methadone. Thus, along with metamphetamine, phenobarbital, morphine and insulin, immunohistochemical detection is also possible for methadone and the intake of this medicament can now be proven morphologically. 相似文献
950.
By means of the new method of Streifenlichttopometrie (SLT) it is possible to record the complete body surface of casualties in a practically photorealistic fashion, i.e. three-dimensionally and in colour. In comparison with the classic method of Photogrammetry Streifenlichttopometrie (SLT) is remarkably faster (10,000 points/s instead of 1 point/s) and in addition the colour of every point measured upon the corpse's surface is instantly recorded. Taking into consideration the resolution required and the qualities of the camera system the body surface is recorded in 'patches', i.e., areas of a defined extension (in the present case 500 mmx500 mmx200 mm) which are marked with a body fixed reference frame to grant the exact matching of the data after the recording process. Length, perimeter, square and volume of the body segments and injuries can be determined. Furthermore the natural colour of the wounds can be used for an immediate classification according to the intensity of the impact forces. In addition the 3-D coordinates of the body surface including the wounds can be transferred into an animated computer simulation for the reconstruction of the traumatic events. 相似文献