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751.
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Venlafaxine is a phenethylamine derivative widely prescribed for the treatment of depression which inhibits both serotonin and norepinephrine reuptake (SNRI). In treatment with antidepressants of patient with depression and other psychiatric disorders there is also increased risk of suicidal thought and behaviour. Several lethal intoxications involving venlafaxine usually among psychotic patients have been reported in the literature. Sample preparation is of the greatest significance for a successful toxicological analysis. The development of simple, effective and rapid extraction procedures of drugs from post-mortem biological samples is a challenge. Headspace-solid phase microextraction (HS-SPME) offers significant advantages such as simplicity, low cost, compatibility with analytical systems, automation and solvent-free extraction. The aim of our work was the optimization of a HS-SPME procedure for the determination of venlafaxine in post-mortem biological samples by gas chromatography (GC) with nitrogen-phosphorous detection (NPD). Venlafaxine was extracted on 100 μm Polydimethylsiloxone Coating-Red (PDMS) SPME fiber and determined by GC-NPD. Salt addition, extraction temperature, preheating and extraction time were optimized to enhance the recovery of the extraction from aqueous solution spiked with venlafaxine. Finally the developed procedure was applied to post-mortem biological samples of a fatally poisoned woman by venlafaxine. The drug was quantified in post-mortem blood gastric and oesophagus contents of the deceased woman. A simple and rapid procedure using HS-SPME was developed for sample preparation of venlafaxine in post-mortem biological samples prior to GC-NPD determination. Validation data was satisfactory, thus enabling application in the toxicological analysis of forensic samples.  相似文献   
754.
A preliminary initial enzyme-linked immunosorbent assay (LUCIO-Direct ELISA kit) and a preliminary DRI enzyme immunoassay were evaluated for drug detection in head hair with respect to lowered cutoff values recommended in Germany for the control of abstinence in cases of re-granting of drivers' licences. Following drug classes were included: cannabinoids, opiates, cocaine like substances, amphetamine, methamphetamine (and methylenedioxyamphetamines), methadone, and benzodiazepines. 759 analyses were performed using LUCIO-Direct ELISA kits and 936 analyses using DRI enzyme immunoassay tests. Sample size for each drug group and immunoassay test reached from 74 to 178. The LUCIO-Direct ELISA kit revealed a sensitivity of 91% for amphetamine up to 98% for methadone (methamphetamine 92%, cocaine 94%, opiates 94%, benzodiazepines 96%) and values of specificity of 72% for methadone up to 89% for amphetamine and benzodiazepines. The test was not useful for a preliminary screening for tetrahydrocannabinol (sensitivity of 65%) in consideration of a suggested cutoff of 0.02 ng/mg. The DRI enzyme immunoassay test was only useful for morphine and cocaine testing at low recommended new cutoff values (0.1 ng/mg) revealing sensitivities of 94% and 99%, respectively.  相似文献   
755.
The synthesis of the designer drug 4-methylthioamphetamine (4-MTA) has been carried out using the well-known Leuckart reaction in four versions. The treatment of 4-methylthiophenylacetone with formamide, mixture of formamide/formic acid, ammonium formate, and mixture of ammonium formate and formic acid followed by acid hydrolysis brought about the formation of 4-MTA contaminated with a number of impurities. The gas chromatography mass-spectrometry (GC-MS) analysis of the reaction mixtures allowed identification of the most prominent impurities, such as diasteromers of N,N-di-[β-(4-methylthiophenyl)isopropyl]amine, N,N-di-[β-(4-methylthiophenyl)isopropyl]methylamine, N,N-di-[β-(4-methylthiophenyl)isopropyl]formamide, the Schiff bases derived from 4-MTA and 4-methylbenzaldehyde (benzaldimine) and 4-methylthiophenylacetone (ketimine) as well as some heterocycles: 4-methyl-5-(4'-methylthiophenyl)pyrimidine, 4-(4'-methylthiobenzyl)pyrimidine, 2,6-dimethyl-3,5-di-(4'-methylthiophenyl)pyridine, 2,4-dimethyl-3,5-di-(4'-methylthiophenyl)pyridine. The correctness of identification was confirmed by independent synthesis of these compounds. Each synthesized reference compound was characterized by means of MS, (1)H and (13)C NMR, and IR methods. The stereochemistry of (RR/SS) diasteromer of N,N-di-[β-(4-methylthiophenyl)isopropyl]amine was confirmed by a crystallographic method.  相似文献   
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The TCU Short Forms contain a revised and expanded set of assessments for planning and managing addiction treatment services. They are formatted as brief (1-page) forms to measure client needs and functioning, including drug use severity and history (TCUDS II), criminal thinking and cognitive orientation (CTSForm), motivation and readiness for treatment (MOTForm), psychological functioning (PSYForm), social relations and functioning (SOCForm), and therapeutic participation and engagement (ENGForm). These instruments facilitate optically-scanned data entry, computerized scoring, and rapid graphical feedback for clinical decisions. The present study (based on 5,022 inmates from eight residential prison treatment programs) examines evidence on scale reliabilities and measurement structures of these tools. Results confirmed their integrity and usefulness as indicators of individual and group-level therapeutic dynamics.  相似文献   
758.
Finding brief effective treatments for criminal justice populations is a major public need. The CJ-DATS Targeted Intervention for Corrections (TIC), which consists of six brief interventions (Communication, Anger, Motivation, Criminal Thinking, Social Networks, and HIV/Sexual Health), were tested in separate federally-funded randomized control studies. In total, 1,573 criminal justice-involved individuals from 20 correction facilities participated (78% males; 54% white). Multi-level repeated measures analyses found significant gains in knowledge, attitudes, and psychosocial functioning (criteria basic to Knowledge, Attitude, and Practices (KAP) and TCU Treatment Process Models). While improvements were less consistent in criminal thinking, overall evidence supported efficacy for the TIC interventions.  相似文献   
759.
A number of pigmented fibre samples were examined with plane polarized light on their dichroic behaviour by optical light microscopy (OLM) and microspectrophotometry with plane polarized light (MSP-PPL). It was found that about half of the samples show a strong dichroic effect and another 20% have a weak dichroism. Both regular (80%) and inversed dichroic effects (20%) occur. The dichroic characteristics of pigmented fibres can be compared to these of sheet polarizers. It is suggested that the dichroic behaviour of pigmented fibres depends strongly on the crystal structure (shape of the pigment grains) and the draw ratio (orientation of the polymer chains).  相似文献   
760.
Footwear impression lifting and enhancement techniques may be affected by several variables introduced during the production of test footwear impressions, thus limiting the usefulness of enhancement technique comparisons and the results obtained. One such variable is the force applied when the impressed mark is being made. Producing consistent test impressions for research into footwear enhancement techniques would therefore be beneficial. This study was designed to control pressure in the production of test footwear impressions when mimicking a stamping action. Twenty-seven volunteers were asked to stamp on two different surfaces and the average stamping force was recorded. Information from the data obtained was used to design and build a mechanical device which could be calibrated to consistently deliver footwear impressions with the same force onto a receiving surface. Preliminary experiments using this device and different contaminants on the footwear sole have yielded consistent and repeatable impressions. Controlling the variable of pressure for the production of test impressions in this study demonstrated that the differences observed were visual (due to the amount of contaminant transferred and subsequent enhancement) and did not affect the replication of outer sole characteristics. This paper reports the development of the device and illustrates the quality of the impressions produced.  相似文献   
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