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281.
282.

Introduction

In the years 1997–2007 in the Forensic Medicine Department, Silesian University of Medicine, Katowice a total of 785 blood samples collected from drivers being the perpetrators of road accidents was tested for the presence of psychoactive drugs.

Methods

The studies took advantage of FPIA (Abbott), ELISA (Neogen), LC–MS and GC FID.

Results

21% of tested samples were positive. In the blood of the driver cannabinoids, amphetamine and its derivatives were most frequently found. Moreover, individual opium alkaloids, their combinations with barbiturates, benzodiazepines or amphetamine, benzodiazepine derivatives (isolated cases), drugs of benzodiazepine group in combination with barbiturates, tramadol or tricyclic anti-depressants (isolated cases), carbamazepine, phenotiazine, cocaine, dibenzepine, benzene, toluene and acetone were determined.

Conclusion

The obtained results showed cannabinoids and amphetamine derivatives to be the most frequent whereas opium alkaloids, barbiturates and benzodiazepines rather rare psychoactive drugs found in the tested blood samples of the drivers involved in the road accidents. The authors suggest screening psychoactive drugs not only in drivers involved in road accidents but also those put through the routine road check procedures. While giving opinions on the influence of the above mentioned drugs on the psychophysical efficiency of road traffic users, drugs and compounds which are not subject to legal control but have an effect on the human psychomotor efficiency and thus, enhance the risk of the road accident should be also taken into account.  相似文献   
283.
To examine whether disproportionate minority contact (DMC) exists in the Netherlands, the representation of minority youth was determined for all stages of the juvenile justice system. Using native Dutch youth as a reference group, the odds ratios (OR) to be registered and arrested as suspect, for alternative punishment and for incarceration, were calculated for the minority youth. In all stages of the juvenile justice system, the ORs for minority youths were considerably higher, except for alternative punishment, having lower ORs. This indicates that DMC exists in the Netherlands. DMC should be politicized and programs should be developed to eliminate this inequality.  相似文献   
284.
The objective of this study was to compare urinary excretion patterns of two cannabinoid metabolites in subjects with a history of chronic marijuana use. The first metabolite analyzed was nor-9-carboxy-delta9-tetrahydrocannabinol (delta9-THC-COOH), the major urinary cannabinoid metabolite that is pharmacologically inactive. The second metabolite 11-OH-delta9-THC is an active cannabinoid metabolite and is not routinely measured. Urine specimens were collected from four subjects on 12-20 occasions > or = 96 h apart in an uncontrolled clinical setting. Creatinine was analyzed in each urine specimen by the colorimetric modified Jaffé reaction on a SYVA 30R biochemical analyzer. All urine specimens analyzed for 11-OH-delta9-THC had screened positive for cannabinoids with the EMIT II Plus cannabinoids assay (cut-off 50 ng/mL) on a SYVA 30R analyzer and submitted for delta9-THC-COOH confirmation by GC-MS (cut-off concentration 15 ng/mL). Eleven-OH-delta9-THC was measured by GC-MS with a cut-off concentration of 3 ng/mL. Both GC-MS methods for cannabinoid metabolites used deuterated internal standards for quantitative analysis. The mean (range) of urinary delta9-THC-COOH concentration was 1153 ng/mL (78.7-2634) with a cut-off of 15 ng/mL. The mean (range) of delta9-THC-COOH/creatinine ratios (ng/mL delta9-THC-COOH/mmol/L creatinine) was 84.1 (8.1-122.1). The mean (range) urinary of 11-OH-delta9-THC concentration was 387.6 ng/mL (11.9-783) with a cut-off of 3 ng/mL, and the mean (range) of 11-OH-delta9-THC/creatinine ratio (ng/mL 11-OH-delta9-THC/mmol/L creatinine) was 29.7 (1.2-40.7). Of the 63 urine specimens submitted for delta9-THC-COOH confirmation by GC-MS, 59/63 urine specimens (94%) were positive for delta9 -THC-COOH and 51/63 (81%) were positive for 11-OH-delta9-THC. Overall, the concentrations of 11-OH-delta9-THC in urine specimens collected > or = 96 h apart were lower than delta9-THC-COOH concentrations in 50/51 of the urine specimens in this population. Further urinary cannabinoid excretion studies are needed to assess whether 11-OH-delta9-THC analyses have a role when assessing previous marijuana or hashish use in chronic users whose urine specimens remain positive for delta9-THC-COOH for an extended period of time after last drug use.  相似文献   
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Subjects with a history of chronic marijuana use were screened for cannabinoids in urine specimens with the EMIT((R)) II Plus cannabinoids assay with a cut-off value of 50 ng/ml. All presumptively positive specimens were submitted for confirmatory analysis for the major urinary cannabinoid metabolite (Delta(9)-THC-COOH) by GC-MS with a cut-off value of 15 ng/ml. Creatinine was analyzed in each specimen as an index of dilution. Huestis and Cone [J. Anal. Toxicol. 22 (1998) 445] reported that serial monitoring of Delta(9)-THC-COOH to creatinine ratios in paired urine specimens collected at least 24h apart could differentiate new drug use from residual Delta(9)-THC-COOH excretion. The best accuracy (85.4%) for predicting new marijuana use was a Delta(9)-THC-COOH/creatinine ratio > or =0.5 (dividing the Delta(9)-THC-COOH to creatinine ratio of specimen 2 by the specimen 1 ratio). In a previous study in this laboratory [J. Anal. Toxicol. 23 (1999) 531], urine specimens were collected from chronic marijuana users at least 24h apart and dilute urine specimens (creatinine values <2.2 micromol/l) were excluded from the data analysis. The objective of the present study was to determine whether creatinine corrected urine specimens positive for cannabinoids could differentiate new marijuana use from the excretion of residual Delta(9)-THC-COOH in chronic users of marijuana based on the Huestis 0.5 ratio. Urine specimens (N=946) were collected from 37 individuals with at least 48h between collections. All urine specimens were included in the data review irrespective of creatinine concentration. The mean urinary Delta(9)-THC-COOH concentration was 302.4 ng/ml, mean Delta(9)-THC-COOH/creatinine ratio (ng/ml Delta(9)-THC-COOH/(mmol/l) creatinine) was 29.3 and the Huestis ratio calculation indicated new drug use in 83% of all sequentially paired urine specimens. The data were sub-divided into three groups (A-C) based on the mean Delta(9)-THC-COOH/creatinine values. Interindividual Delta(9)-THC-COOH/creatinine mean values ranged from 2.2 to 13.8 in group A (264 specimens, N=15 subjects) where 80.7% of paired specimens indicated new drug use. In group B, mean Delta(9)-THC-COOH/creatinine values ranged from 15.3 to 37.8 in 444 specimens (N=14 subjects) and 83.3% of paired specimens indicated new drug use. In group C, individual mean Delta(9)-THC-COOH/creatinine values were >40.1 (41.3-132.5) in 238 urine specimens (N=8 subjects) and 85.3% of paired urine specimens indicated new marijuana use. Correcting Delta(9)-THC-COOH excretion for urinary dilution and comparing Delta(9)-THC-COOH/creatinine concentration ratios of sequentially paired specimens (collected at least 48h apart) provided an objective indicator of new marijuana use in this population.  相似文献   
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Time-of-flight secondary ion mass spectrometry (TOF-SIMS) was utilized to obtain characteristic mass spectra from three different smokeless powders and six different black powder samples. In these mass spectra, peaks indicative of both the organic and inorganic additive constituents in the gunpowders were observed. TOF-SIMS was able to successfully differentiate between the different black and smokeless gunpowder samples analyzed with the aid of principal components analysis (PCA), a multivariate statistical analysis approach often used to reduce the dimensionality of complex data. TOF-SIMS was also used to obtain information about the spatial distribution of the various additives contained within the gunpowder samples. SIMS imaging demonstrated that that the samples could potentially be characterized by their 2-D structure, which varied from sample to sample. These results clearly demonstrate the feasibility of utilizing TOF-SIMS as a tool for the characterization and differentiation of gunpowder samples for general forensic applications.  相似文献   
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