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61.
Improvements in detection limits/sensitivity and lower sample consumption are potential benefits of reducing PCR reaction volumes used in forensic DNA typing of crime scene samples. This premise was studied first with experimental mixtures and a nine-loci megaplex, which demonstrated stochiometric amplification and accurate detection. Next, adjudicated casework samples were subjected to amplification under 15 different template DNA to PCR reaction volume ratios. Reduction of PCR reaction volume and DNA down to 10 microL and 0.500 ng, respectively, produced identical profiles with the same signal intensity and heterozygous allele peak height ratio (HR). Reduction to 5 microL and 0.063 ng yielded HR values that were slightly affected in one to three STR loci. PCR reaction volume reduction can enhance detection and sensitivity while reducing the consumption of irreplaceable crime scene samples.  相似文献   
62.
Two species of blow flies (Diptera: Calliphoridae) were reared on tissues from rabbits administered different dosages of morphine. These species, Protophormia terraenovae and Calliphora vicina are among the first wave of insects colonizing a dead body. Two series of 3 rabbits were given dosages of 10, 20, and 40 mg/h of morphine over a 3 h period via ear artery perfusion. A morphine blood level plateau was attained after 1 h of perfusion. Two other rabbits were used as controls. Samples of tissues collected from rabbits using a coelioscopic technique were determined to have morphine concentrations similar to those encountered in human overdoses and were correlated with dosages of morphine administered. All samples from control rabbits were negative for morphine. Larvae and puparia of both species were regularly collected from each rabbit for toxicological analysis. Concentrations of morphine in larvae reared on rabbit carcasses containing morphine were significantly lower than concentrations found in the tissues. There was a decrease in concentration in morphine observed in transition from feeding 3rd instar larva to puparium. A correlation between larval concentration and tissue concentration was found only in feeding 3rd instar larvae.  相似文献   
63.
Morphine was detected by immunohistochemistry on sections of third stage larvae of Calliphora vomitoria (Diptera, Calliphoridae) reared on minced beef meat previously treated with morphine hydrochloride. The detection was performed with an avidin-biotin-peroxidase-complex method. Positive specimens showed specific staining of the haemolymph and a more intense immunoreaction in an area located at the limit between exocuticle and endocuticle. These results constitute an evidence of morphine accumulation inside the cuticle of Diptera larvae during their development. During the pupariation, the larval cuticle is transformed into the sclerotized puparium. This study consequently points out the possibilities of analyzing empty pupariae when suitable tissues or living necrophagous insects are absent.  相似文献   
64.
Diabetes mellitus is a chronic metabolic illness responsible for a great number of deaths. In postmortem diagnosis, because of the difficulty involved in interpreting blood glucose levels and relatively nonspecific pathologic features, biochemical markers in vitreous humor are useful. The aim of this study was to compare the results obtained for the combined determination of lactate and glucose with fructosamine levels recorded in the vitreous humor of two diagnostic groups (one diabetic and the other nondiabetic). The authors intended to ascertain the capacity of different markers measured in vitreous humor to diagnose diabetes mellitus. Fifty-one cadavers (mean age, 58.7 years; standard deviation, 17.09) were studied. The mean postmortem interval was 16.4 hours (standard deviation, 9.05). Cases were assigned to two diagnostic groups according to whether they were previously diagnosed as either diabetic or nondiabetic. Statistically significant differences for glucose, fructosamine, and the sum values of glucose and lactate were found between the two diagnostic groups. The highest levels were obtained in the group of cases with a previous diagnosis of diabetes mellitus. After the comparison of receiver operating characteristic curves, the sum values of glucose and lactate in vitreous humor is a better predictor of antemortem diabetes mellitus than the fructosamine.  相似文献   
65.
1-Aryl-piperazine compounds are, depending on their substituents, selective for certain serotonin receptors and together with their easy availability and their so-called legal status, this group of psychoactive compounds are potential designer drugs-of-abuse. Internet in that respect is an important source of information and distribution facilities. Because this development may have consequences for the interpretation of future clinical and forensic toxicological case studies, some analytical aspects of 1-benzyl-piperazine (BZP), 1-[4-methoxyphenyl]-piperazine (pMeOPP) and 1-[3-trifluoromethylphenyl]-piperazine (TFMPP) were studied. BZP was not detected by the AxSYM FPIA technology designed to determine amphetamine-like compounds, but had showed some cross reactivity with EMIT d.a.u.. The cross reactivities at 300 and 12,000ng/ml (RS)-amphetamine equivalents were 0.4 and 1.3%, respectively. Although BZP was not identified directly by the REMEDi HS Drug Profiling System, it can be detected by this HPLC/UV scanning system. Using GC/NPD without derivatisation, BZP, pMeOPP and TFMPP can be analysed for and applying GC/MS without or with acetylation or trifluoroacetylation, these compounds can be identified unambiguously. The usefulness of GC/NPD and GC/MS in this respect was demonstrated by the quantitative and qualitative analysis of the content of a capsule with the synthetic stimulant A2, which proved to contain 86.4mg of BZP.  相似文献   
66.
Since the suicide—homicide of 53 members of the Order of the Solar Temple in 1994 and the gas attempt by Aum Shinrikyo in Tokyo's subway in 1995, a number of European states have decided to fight against sects. France and Belgium are in the forefront of this battle. Both countries have set up official observatories of sects and state agencies involving various ministries to combat them. Preventive policies targeting sects are being carried out. In Belgium, the Anthroposophic Society, a philosophical movement listed as 1 of 189 sects suspected of being dangerous, has sued one federal entity that printed unfounded accusations against their movement in a widely distributed brochure against sects. The same Anthoposophic Society has also petitioned the Court of Arbitration to have the law establishing an observatory of sects annuled. This report deals with both legal actions.  相似文献   
67.
Why do people vote? An experiment in rationality   总被引:1,自引:0,他引:1  
Blais  André  Young  Robert 《Public Choice》1999,99(1-2):39-55
The study presents the findings of an experiment conducted during the 1993 Canadian fedeal election campaign. Students in two universities were exposed to a ten-minute presentation about the rational model of voting and the ‘paradox’ that so many people vote when it is apparently irrational on a cost-benefit basis. Our data indicate that exposure to the presentation decreased turnout in the election by seven percentage points. This result contributes to the debate abut the effect of rational-choice models on real political behavior. More important, the experimental panel data permit the presentation's effect to be decomposed, and this helps explain why people do vote. In this study, turnout was reduced mainly because the presentation diminished the respondents' sense of duty, an effect that was indirect, because there was no reference in the presentation to such motives. Framing the voting act in rational-choice terms induced some students to reconsider whether they should feel obliged to vote.  相似文献   
68.
In order to establish an animal model for entomotoxicological studies, the kinetics of morphine elimination from blood after a single intravenous injection of morphine and the concentration of morphine in tissues following a continuous perfusion were studied. The aim of these experiments was to obtain controlled morphine tissue concentrations similar to those encountered in fatal human heroin overdoses. These tissues can be used as a food source for developing fly larvae in entomotoxicological studies. In the single injection experiment, seven rabbits were administered 1 or 2 mg/kg body weight of morphine chlorhydrate via the main ear artery. Blood samples of 200 microL were removed regularly via a catheter. Morphine concentration was determined using RIA techniques. Morphine was found to be first rapidly distributed and then slowly eliminated, following a two-exponential equation. Elimination of morphine from blood can be described as a two-compartment model. Constants of the equation were determined using the Kaleidagraph program. Using those constants, the main pharmacokinetics parameters were calculated. Results of these parameters showed the following: clearance from 13.3 to 16.2 L.h.1, half-life of the distribution phase from 0.6 to 0.9 min, and half-life of the elimination phase from 21 to 26 min. These results were used to calculate the rate of perfusion of morphine for rabbits to obtain desired, controlled, and constant concentrations of morphine in tissues. In the second experiment, three rabbits received a perfusion of morphine intravascularly at a rate of 2 mg/kg/h for a period of 3 h. These rabbits were sacrificed and analyses performed on several abdominal and thoracic organs. Results showed that the concentrations of morphine differed according to the organ analyzed, but were reproducible for organs between animals. These concentrations were similar to those normally encountered in cases of human death due to heroin overdoses.  相似文献   
69.
Abstract: This study examines the use of influence tactics by Human Resources managers with the members of the Quebec public-sector management team. The results indicate that they use a large number of influence tactics, that they use more frequently “soft” tactics than “hard” ones or “neither soft nor hard” ones, and they choose their tactics based on a cost-benefit analysis. Furthermore, the analyses reveal that respondents whose feelings of self-efficacy are high will not attempt to influence or use “soft” tactics any more frequently than respondents with low feelings of self-efficacy. Finally, the results indicate that our respondents exercise influence effectively.  相似文献   
70.
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