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881.
882.
Benzo[f]ninhydrin was compared to ninhydrin for fingerprint development on paper. Overall, the performance of ninhydrin on exhibits was slightly better than that of benzo[f]ninhydrin. The significant advantages of the benzo[f]ninhydrin over ninhydrin were the much stronger fluorescence it gave after treatment with zinc salts and a slightly quicker reaction under ambient conditions. This fluorescence is, however, similar to that obtained with other reagents, such as DFO or ninhydrin analogs. These advantages apparently are not sufficient to justify regular usage of benzo[f]ninhydrin, especially when one considers its low solubility and high cost.  相似文献   
883.
In the years from 1982 to 1995, 20,504 autopsy cases were examined at the Departments of Forensic Medicine in Hamburg and Greifswald. In 103 cases death was caused by kicking. In the Greifswald area, the occurrence of kicking as the cause of death could be demonstrated in 68 cases (30% of all homicides), which is in contrast to the observations in Hamburg, were kicking amounted to only 2.5% of the homicides. Most of the victims (average age 44 years) were under the influence of alcohol (mean blood alcohol concentration 1.75/1000), and most were on social support. The victims often showed other signs of blunt trauma such as blows with the fist and strangulation. In a few cases, cutting and stabbing wounds were also found. In the majority of cases death was due to severe haemorrhages and aspiration of blood in addition to the direct effects of the head injuries. The crimes were committed by one person in 46 cases, two in 20 and three in 4 cases. The perpetrators (average age 27.6 years) were always younger than the victims. Case reports show that fatal kicking was mostly triggered by relatively trivial arguments. None of the incidents were preplanned by the perpetrators. In contrast to an expected higher incidence of kicking deaths in the urban area of Hamburg, these crimes occurred ten times more frequently in the rural area of Greifswald.  相似文献   
884.
Hair analysis by immunological methods from the beginning to 2000   总被引:2,自引:0,他引:2  
Immunoassays for hair testing must satisfy three requirements: (1) They must have cross-reactivity with parent drug and lipophilic metabolites actually found in hair (2) they must not experience interference from the dissolved hair matrix and (3) they must be titered for cutoffs appropriate to the drug concentrations found in hair. Because the analytes found in hair after drug use are generally the parent drug or its lipophilic metabolites, immunoassays developed and intended for urine testing are not suitable for hair. Immunoassays whose antibodies are bound to a solid support, such as coated-tube radioimmunoassay or coated-plate ELISA tests, experience less matrix interference than those which use other means of separation of bound and free fractions. Homogenous assays are not suitable for hair testing because the hair matrix frequently interferes in the detection of the signal. Historically radioimmunoassays for drugs of abuse were first used for detecting drugs in hair. Currently ELISAs and coated-plate 96 well microplate EIAs are employed for screening hair digests or extracts for drugs. The optimum cutoffs for immunoassays for drugs in hair should be chosen based on the analyte concentration which produces the fewest false positive or false negative results when applied to tests of hair from known users and non-users of drugs. A hair immunoassay test at these cutoffs should have a sensitivity and specificity of better than 90%. The predictive value of the test will depend on the prevalence of drug use in the tested population. Cutoffs or decision thresholds for immunoassays used for screening for drugs should not be at the limit of detection of the assay because that produces a very large incidence of false positives. Because immunoassays are ligand-binding assays, they have a short range of linearity with low precision at both ends of the range. In the future, immunoassays will continue to be used for screening hair and other matrices for drugs of abuse because they provide rapid, inexpensive automated procedures for separating negative specimens from those which are suspected of containing drugs. For forensic purposes, all positive results must be confirmed by an independent analysis using a procedure based on a different property of the analyte. An immunoassay test should not be confirmed by a second immunoassay test but by a chromatographic test performed on a different dissolved or extracted aliquot of the original specimen.  相似文献   
885.
The aim of the present study was to establish an analytical method for the determination of clozapine in sweat and to determine whether the clozapine level in hair and sweat were correlated to the daily dose of clozapine delivered to patients. Twenty-six subjects treated with clozapine at 200-700 mg/day for refractory psychosis were included in the study. Clozapine was determined in plasma by liquid chromatography coupled to a diode array detection system, after extraction with an organic solvent at pH 9.5. Clozapine was extracted from hair and sweat patches specimens by incubation in methanol overnight at 40 degrees C. The residues were analyzed by gas chromatography coupled to mass spectrometry in the electronic impact mode of detection. It was possible to determine clozapine in concentrations ranging from 30 to 1016 ng/ml in plasma (n = 22), from 0.17 to 34.24 ng/mg in hair (n = 23) and from 49 to 5609 ng/patch in sweat (n = 20). Preliminary results suggest a lack of correlation between daily regimen of clozapine and plasma levels of the drug. Therefore, a better dose-concentration relationship was observed in our study between daily dose and hair concentration (r = 0.542, P < 7%) or between daily dose and sweat concentration (r = 0.589, P < 6%), but with wide variations for patients at the same posology. However, the idea of using quantitative drug measurements in hair or sweat to ascertain whether a patient has taken his treatment exactly as prescribed will remain inapplicable.  相似文献   
886.
Homicides due to asphyxia are relatively uncommon. To better understand the presentation of such cases, the files of the Bexar County Medical Examiner's Office were reviewed from January 1, 1985, through December 31, 1998, for all such homicides. A total of 133 cases were found. The largest category was ligature strangulation with 48 deaths (21 male, 27 female). Petechiae were present in the conjunctivae and/or sclerae in 86% of the cases; fractures of the hyoid and/or thyroid cartilage were present in 12.5%. There were a total of 41 deaths from manual strangulation (27 female, 14 male). Petechiae were present in 89% of the cases. In cases of manual strangulation, fractures of the hyoid, thyroid, or cricoid cartilage were found in all the male victims and slightly more than one half of the female victims. Twenty-six cases of suffocation were found; 20 of the victims were < or =2 years of age. Only 1 of these children had petechiae and/or scleral hemorrhage. Five deaths were due to choking. Three of the deaths involved adults who were gagged; 2 deaths involved infants with foreign material pushed into the mouth. Other categories of asphyxia were as follows: 9 deaths due to more than one form of asphyxia; 1 death due to hanging, and 3 deaths due to drowning. Rape was the motive in 66% of the female victims of ligature strangulation and 52% of those due to manual strangulation.  相似文献   
887.
888.
889.
The ongoing contact of adolescents with high school staff may provide an opportunity for the early identification and effective management of suicidal behavior. In this study, the knowledge, attitude, and experience of 80 high school professionals regarding adolescent suicide were assessed through semistructured personal interviews. Respondents identified more than 30 signs of potential vulnerability — manifestations of depression, verbal and written cues, isolation, and self-destructive behaviors. Among predisposing factors, those related to alienation within the family were most prominent. Other important risk factors were low self-esteem, difficulty in peer relationships, and economic or ethnic differences from other students. When suicidal behaviors occurred, respondents saw students and staff as attempting to be helpful; families were more often viewed as defensive.  相似文献   
890.
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