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991.
Rabbit carcasses were used to compare rates of decomposition and associated assemblages of Diptera at four discernable habitat types in Kuwait; a country of a region with a paucity of such reference data. Carcasses in an urban habitat showed faster decomposition (as measured by percentage weight loss) than in agricultural, coastal or desert habitats, even with accumulated degree days (ADD) as the explanatory variable (t=2.73, df=34, p=0.010) to compensate for temperature differences. Taxa of Diptera at the four habitats became more similar as decomposition progressed, suggesting such differences between habitats were not marked. The occurrence of Chrysomyia megacephala and Lucilia sericata had not previously been recorded in Kuwait.  相似文献   
992.
Pearson correlation coefficients were applied for the objective comparison of 30 black gel pen inks analysed by laser desorption ionization mass spectrometry (LDI-MS). The mass spectra were obtained for ink lines directly on paper using positive and negative ion modes at several laser intensities. This methodology has the advantage of taking into account the reproducibility of the results as well as the variability between spectra of different pens. A differentiation threshold could thus be selected in order to avoid the risk of false differentiation. Combining results from positive and negative mode yielded a discriminating power up to 85%, which was better than the one obtained previously with other optical comparison methodologies. The technique also allowed discriminating between pens from the same brand.  相似文献   
993.
dl-3,4-methylenedioxymethamphetamine (MDMA) and methamphetamine are commonly used illicit drugs that are thought to impair driving ability. The Standardized Field Sobriety Tests (SFSTs) are utilized widely to detect impairment associated with drugs other than alcohol in drivers, although limited evidence concerning MDMA and methamphetamine consumption on SFST performance exists. The aim of this study was to evaluate whether the SFSTs were a sensitive measure for identifying the presence of the specific isomer d-methamphetamine and MDMA. In a double-blind, within-subject, counter-balanced and placebo-controlled study, 58 healthy and abstinent recreational drugs users were administered three treatments: 100mg of MDMA, 0.42 mg/kg d-methamphetamine, and placebo. For each condition the SFSTs were administered at 4 and 25 h post treatment. d-methamphetamine was not found to significantly impair SFST performance unlike MDMA, which significantly impaired SFST performance in comparison to placebo with 22% of the sample failing the test at the 4h testing time-point. No differences were observed at the 25 h testing time-point for any of the conditions. It was concluded that the SFSTs are not efficient in identifying the presence of low level d-methamphetamine, and are significantly better at detecting the presence of MDMA at the levels assessed.  相似文献   
994.
We report the case of a 27 year old man who was injured by a Taser gun device which penetrated the frontal part of the skull and damaged the underlying frontal lobe. Cerebral penetration was revealed by a brain CT scan. A neurosurgical procedure was required to remove the dart from the skull and brain and the evolution was successful allowing discharge of the patient one week later. There were no additional lesions, particularly electrifying lesion, as only one probe had penetrated the skull. We also observed the length of a Taser dart is sufficient to allow brain penetration. Fortunately, no infection or neurological complication occurred following brain injury. This case study underlines the potential risk induced by the use of Taser stun gun. Although generally regarded as a safe alternative, serious injuries have however been reported and questions regarding the safety of the device still remains unresolved.  相似文献   
995.
In developed countries, sudden infant death syndrome (SIDS) represents the most prevalent cause of death in children between 1 month and 1 year of age. SIDS is a diagnosis of exclusion, a negative autopsy which requires the absence of structural organ disease. Although investigators have confirmed that a significant percentage of SIDS cases are actually channelopathies, no data have been made available as to whether other sudden cardiac death-associated diseases, such as hypertrophic cardiomyopathy (HCM), could be responsible for some cases of SIDS. The presence of a genetic mutation in the sarcomeric protein usually affects the force of contraction of the myocyte, whose weakness is compensated with progressive hypertrophy and disarray. However, it is unclear whether in the most incipient forms, that is, first years of life, the lack of these phenotypes still confers a risk of arrhythmogenesis. The main goal of the present study is to wonder whether genetic defects in the sarcomeric proteins, previously associated with HCM, could be responsible for SIDS. We have analysed 286 SIDS cases for the most common genes implicated in HCM in adults. A total of 680 mutations localised in 16 genes were analysed by semi-automated matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDITOF-MS) using the Sequenom MassARRAY(?) System. Ten subjects with completely normal hearts showed mutated alleles at nine of the genetic variants analysed, and one additional novel mutation was detected by conventional sequencing. Therefore, a genetic mutation associated with HCM may cause sudden cardiac death in the absence of an identifiable phenotype.  相似文献   
996.
We evaluated the performance of Emit(?) II Plus 6-Acetylmorphine Assay for human urine screening on the Viva-E(?) analyzer. Precision was evaluated using the cutoff and ±25% controls. Recovery and linearity were studied by spiking 6-acetylmorphine (6-AM) into human urine pools. Accuracy was evaluated using urine specimens and the results were compared to those from GC/MS. Cross-reactivity with structurally related drugs was assessed at different cross-reactant concentrations. Interferences were assessed in the presence of 7.5 and 12.5 ng/mL of 6-AM. The qualitative repeatability coefficients of variation (CV's) ranged from 0.3% to 0.4% and the within-lab CV's ranged from 2.0% to 2.2%. In analyte units (ng/mL), the repeatability CV's ranged from 1.3% to 2.2% and the within-lab CV's ranged from 2.6% to 4.3%. The limit of detection of the assay was found to be 2.1 ng/mL. Recovery was within 15% of expected value. Linearity was 2.1-20 ng/mL. Method comparison showed 99% agreement with GC/MS. The assay had minimal cross-reactivity with morphine, morphine-3-glucuronide, morphine-6-glucuronide and other opioids. No interference was observed with endogenous interferences and structurally unrelated drugs. The assay correctly classified CAP survey samples. The Emit(?) II Plus 6-Acetylmorphine Assay will be a suitable screening method for urine specimens in both qualitative and semi-quantitative analyses.  相似文献   
997.
Atomoxetine (ATX) is a potent inhibitor of the noradrenaline reuptake transporter approved since 2002 for the treatment of attention-deficit/hyperactivity disorder (ADHD) in children, adolescents, and adults as alternative treatment to methylphenidate. A procedure based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) has been developed for the determination of ATX and its main metabolites (4-hydroxyatomoxetine - 4 hydroxyATX - and N-desmethylatomoxetine - des-methylATX) in hair of one treated child and five treated adolescents. Since hair samples can be easily collected without the need for specials skills and exposing a patient to discomfort, hair testing of ATX and eventually of its metabolites should be useful, especially in case of pediatric patients, to check compliance in a wider time-window. After addition of duloxetine as internal standard, hair samples were overnight digested with 2ml 1M NaOH at 45°C. Then, analytes were extracted from alkaline solution with two different 2ml aliquots of tert-butyl methyl ether. Chromatographic separation was achieved at ambient temperature using a reverse-phase column and a mobile phase of 40% of water-60% 5mM ammonium acetate, 50mM formic acid, 4mM trifluoroacetic acid in acetonitrile-water (85:15, v/v). The mass spectrometer was operated in positive ion mode using multiple reaction monitoring. The method was linear over the concentration range 0.2-50ng/mg hair for the all analytes under investigation, with an intra- and inter-assay imprecision and inaccuracy always less than 20% and an analytical recovery between 33.1% and 76.1%, depending on the considered analyte. Only ATX and 4-hydroxyATX were detected in hair samples with concentrations varying from 0.2 to 2.0ng/mg hair and from 0.3 to 1.0ng/mg, respectively. Notwithstanding the absence of any dose-hair concentration relationship, hair monitoring of ATX and concomitant medications commonly administrated in ADHD children and adolescents can be crucial in verifying long-term compliance to prescribed medication in individuals displaying a non negligible tendency to refuse drugs and to lie on the adherence to therapy as a specific symptom of the disease.  相似文献   
998.
Several studies have indicated that there are potential environmental sources of particles resembling inorganic primer found in gunshot residues (GSR); as a consequence examiners are reluctant to unambiguously assign the origin of inorganic particles. If organic gunshot residues (OGSR) were found in combination with inorganic particles, the possibility of environmental sources could be potentially eliminated, thereby significantly enhancing the strength of the evidence. Methods have been previously described whereby GSR specimens can be analysed for the presence of OGSR or inorganic GRS (IGSR). However, no methods have been reported that allow the analysis of both OGSR and IGSR on the same specimen. Described in this article is a direct method using desorption electrospray ionisation-mass spectrometry (DESI-MS) for the detection of methyl centralite (MC), ethyl centralite (EC) and diphenylamine (DPA) on adhesive tape GSR stubs typically used for scanning electron microscopy-energy-dispersive X-ray (SEM-EDX) analysis. The optimisation of numerous parameters was conducted using an experimental design. The results indicate that direct analysis of these organic components of GSR is possible although some limitations were also identified. This initial investigation has also indicated that subjecting stubs to DESI analysis does not interfere with subsequent SEM-EDX analysis of primer residues; therefore the technique described herein allows a comprehensive examination of GSR that would be highly probative in the event that both OGSR and IGSR are detected in the same specimen.  相似文献   
999.
1000.
LUCIO-Direct-enzyme linked immunosorbent assay (ELISA) tests were validated for the screening of drugs of abuse cannabis, opiates, amphetamines and cocaine in urine for the new German medical and psychological assessment (MPA) guidelines with subsequent gas chromatographic-mass spectrometric (GC-MS) confirmation. The screening cut-offs corresponding to 10 ng/mL 11-nor-delta-9-tetrahydrocannabinol-9-carboxylic acid (THC-COOH), 50 ng/mL amphetamine, 25 ng/mL morphine and codeine and 30 ng/mL benzoylecgonine were chosen at the point where the number of false negatives was lower than 1%. Due to their accuracy, ease of use and rapid analysis, these ELISA tests are very promising for cases where a large proportion of the tests are expected to be negative such as for abstinence monitoring as part of the driving licence re-granting process.  相似文献   
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