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211.
There is consistent evidence that impulsivity is linked to tobacco consumption and to symptomatology in schizophrenia. In the current study, we propose a new integrative model of the relationship between impulsivity, psychopathological symptoms, and tobacco status in patients with paranoid schizophrenia. We investigated 33 paranoid schizophrenia patients and 37 healthy controls using a battery of psychopathological scales included the Structured Clinical Interview for DSM-IV (SCID), the five-factor model of the Positive and Negative Symptom Scale (PANSS), the Barratt Impulsiveness Scale (BIS-10), and the UPPS Impulsive Behavior scale (UPPS). Step-wise regression analysis revealed that positive factor of the PANSS and tobacco status contributed positively and significantly to the explained variance of impulsivity. In addition, non-planning impulsivity and sensation-seeking emerged as significant predictors of tobacco status, while smoking predicted non-planning impulsivity and sensation-seeking. Our results suggest that the relationship between sensation-seeking and tobacco use is reciprocal and proposes a new integrative model of the relationship between impulsivity, positive symptoms and tobacco status in patients with paranoid schizophrenia. However, the exact mechanisms for these relationships deserve further investigation.  相似文献   
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Retained bullets and fragments following a civilian gunshot injury are quite frequent in practical neurosurgery. It is usually possible to extract the foreign body surgically, while rare cases are conservatively treated because of technical reasons. Conservative treatment may present complications, and a rare form of this presentation is migration of the bullet. A 20-year-old man presented with migrating bullet from a supratentorial to opposite infratentorial area. We consider that in the migrating bullet fragment cases, if there is no contraindication, the most reasonable treatment is its urgent surgical removal. This report reveals a supratentorial bullet migrating to the infratentorial contralateral area, and related literature considering the different mechanisms of migration is discussed.  相似文献   
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A new rapid and sensitive high-performance liquid chromatography (HPLC) method has been developed for the simultaneous identification and quantification in human plasma of the 13 most commonly prescribed beta-blockers and one active metabolite-atenolol, sotalol, diacetolol, carteolol, nadolol, pindolol, acebutolol, metoprolol, celiprolol, oxprenolol, labetalol, propranolol, tertatolol and betaxolol. It involves liquid-liquid extraction procedures followed by liquid chromatography coupled to photodiode-array UV detection with a fixed wavelength at 220 nm for quantification. Compounds were separated on a 5 microm Hypurity C(18) (ThermoHypersil) analytical column (250 mm x 4.6 mm, i.d.) using a gradient of acetonitrile-phosphate buffer pH 3.8 at a flow rate of 1.0 ml/min. The total analysis time was 26 min per sample. Extraction recoveries were between 74 and 113% for the polar compounds and between 20 and 56% for the most apolar compounds. Calibration lines were linear in the range from 25 to 1000 ng/ml for all compounds excepted carteolol and nadolol (50-1000 ng/ml), all of them with coefficients of determination (r2 values) >/=0.994. Limits of detection (LODs) ranged from 5 to 10 ng/ml. Intra-assay and inter-assay precision and accuracy were studied at two concentration levels (100 and 500 ng/ml). The intra-assay coefficients of variation (CVs) for all compounds were 相似文献   
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Fenarimol (Rubigan) is a pyrimidine ergosterol biosynthesis inhibitor used as a systemic fungicide. The authors present a fatal fenarimol intoxication case analysed in the Forensic Toxicology Service of the National Institute of Legal Medicine. The results were used to compare two different HPLC techniques, regarding selectivity and sensitivity: an HPLC system with a diode array detector (DAD) and an HPLC system with a DAD and a mass spectrometry detector (MSD) with an electrospray interface. All biological samples were submitted to a solid-phase extraction procedure. The detection and quantification limits of fenarimol, linearity, precision and accuracy were evaluated. The fenarimol concentration levels determined were of 89.0 mg/ml in gastric contents, 1.9 mg/g in liver and 0.4 mg/g in kidney. Blood was not available at autopsy. No published data related to fenarimol self-poisoning were found, so it was not possible to interpret the results obtained by comparison with toxic/lethal levels.  相似文献   
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We report the results of Spanish and Portuguese working group (GEP) of International Society of Forensic Genetics (ISFG) Collaborative Exercise 2001-2002 on mitochondrial DNA (mtDNA) analysis. 64 laboratories from Spain, Portugal and several Latin-American countries participated in this quality control exercise. Five samples were sent to the participating laboratories, four blood stains (M1-M4) and a sample (M5) consisting of two hair shaft fragments. M4 was non-human (Felis catus) in origin; therefore, the capacity of the labs to identify the biological source of this sample was an integral part of the exercise. Some labs detected the non-human origin of M4 by carrying out immuno-diffussion techniques using antihuman serum, whereas others identified the specific animal origin by testing the sample against a set of animal antibodies or by means of the analysis of mtDNA regions (Cyt-b, 12S, and 16S genes). The results of the other three human blood stains (M1-M3) improved in relation to the last Collaborative Exercises but those related to hairs yielded a low rate of success which clearly contrasts with previous results. As a consequence of this, some labs performed additional analysis showing that the origin of this low efficiency was not the presence of inhibitors, but the low quantity of DNA present in these specific hair samples and the degradation.As a general conclusion the results emphasize the need of external proficiency testing as part of the accreditation procedure for the labs performing mtDNA analysis in forensic casework.  相似文献   
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