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201.
202.
In forensic evidence, gamma-hydroxybutyric acid (GHB) has frequently been encountered in one of its salt forms (gamma-hydroxybutyrate), but has also been encountered in its free acid form (GHB). Owing to the physical properties, encounters of the free acid have been largely restricted to forensic exhibits comprising aqueous solutions, such as acidic beverages that have been "spiked" or formulated with GHB salts or gamma-butyrolactone (GBL). The analysis of GHB free acid presents particular difficulties including the potential for altering the original proportions of GHB free acid, GHB carboxylate, and GBL in the course of analysis, and discrimination between GHB free acid and carboxylate forms. In this work, the formation of GHB free acid in aqueous solutions (water and/or D2O) was studied as a function of solution pH. Proton nuclear magnetic resonance (1HNMR) and Fourier-transform infrared spectrometry (FT-IR) measurements were obtained on freshly prepared mixtures of NaGHB and HCl stock solutions representing a series of points along the GHB titration curve. Both 1HNMR and FT-IR were shown to track the changing proportions of GHB free acid and carboxylate forms as a function of pH, while simultaneously monitoring for the formation of the lactone (GBL). The results were consistent with acid-base conversion behavior for a carboxylic acid. 1HNMR was shown to provide an ideal means for analysis of aqueous-based GHB/GBL forensic exhibits based on simple dilution of the neat liquid exhibit, without altering the original proportions of GHB free acid, carboxylate, and GBL in the samples. 相似文献
203.
Schmidt LA Wiley J Dohan D Zabkiewicz D Jacobs LM Henderson S Zivot M 《Journal of health politics, policy and law》2006,31(5):945-980
Sharp declines in welfare rolls since the passage of welfare reform legislation have led many to label it a social policy success. Using data from prereform and postreform samples of welfare applicants and recipients, as well as ethnographic data on welfare reform implementation, we examine three hypotheses based on concerns raised during the welfare reform debate about the possible effects of new policies on substance abusers and addicts: First, they would be "scared off," or discouraged from applying to aid by welfare's new requirements surrounding work and treatment. Second, they might be "weeded out," or face discrimination in the application process because of concerns about the difficulty of moving them successfully from welfare to work. Third, they might be "bumped down," or shifted to local aid programs rather than moving from welfare to self-sufficiency. Our empirical analysis finds no evidence of scaring off or weeding out, and some evidence of bumping down. Using ethnographic data, we offer some possible explanations for these findings by placing them in the context of policy change and implementation in the years following welfare reform. 相似文献
204.
Capelli C Arredi B Baldassari L Boschi I Brisighelli F Caglià A Dobosz M Scarnicci F Vetrugno G Pascali VL 《Forensic science international》2006,159(1):64-70
Three geographic areas of Italy have been sampled and genotyped for 9 Y chromosome STRs: DYS19, DYS385, DYS388, DYS389 I and II, DYS390, DYS391, DYS392, DYS393. Sampling was focused on residents of small areas, well distant from major urban centres. Only individuals whose grandfather would live in the same area were included. A total of 210 unrelated individuals were collected. Distribution of genetic variation across the three samples and comparison with previously published Italian database indicated that so far Y chromosome diversity has been only partially explored in the Italian Peninsula. 相似文献
205.
Bermejo AM López P Alvarez I Tabernero MJ Fernández P 《Forensic science international》2006,156(1):2-8
A method for the simultaneous determination of cocaine (COC) and cocaethylene (CE) in human hair was developed, using solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) as analytical technique to identify and quantify the drugs. Selected ion monitoring (SIM) mode was used to obtain higher sensitivity. The deuterated-labeled analogues were used as internal standards. The detector response was linear for the drugs studied over the range 0.4-15 ng/mg, with correlation coefficients higher than 0.995. The coefficients of variation oscillated between 0.65% and 14.18% and the accuracy was in the range from 0.73% to 11.20%. The limits of quantitation and detection were found to be acceptable. Finally, this method was applied to 15 hair samples from cocaine users, obtaining positive results in all cases. The mean concentrations were 5.39 ng/mg (range: 0.43-8.98 ng/mg) for cocaine and 1.11 ng/mg (range: 0.42-2.23 ng/mg) for cocaethylene. 相似文献
206.
Bernal LP Borjas L Zabala W Portillo MG Fernández E Delgado W Tovar F Lander N Chiurillo MA Ramírez JL García O 《Forensic science international》2006,161(1):60-63
Allele frequencies for 15 short tandem repeats (STRs) autosomal loci (D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S51, D5S818 and FGA, included in the AmpFLSTR Identifiler, Applied Biosystems) were studied in the city of Maracaibo, Venezuela and were compared with other published Latin-American populations for the same loci. Population and forensic parameters were estimated. 相似文献
207.
208.
The short-time autolysis of hearts was regarded as a model of ischaemic heart failure. Therefore, isolated rat hearts were subjected to 30--120 min autolysis in a Locke solution at 37 degrees C. Electron microscopic examinations and myofibrillar preparations were made from the autolysed heart ventricles. The myofibrillar proteins were resolved by SDS-polyacrylamide gel electrophoresis. After 30 min autolysis the amount of a protein of 192,000 daltons greatly increased. At the same time on the electron micrographs the focal destruction of filament destruction on the A filament area and the mitochondrial structure altered too. After 60 min autolysis another protein of 36,400 daltons appeared. On the electron micrographs the focal desintegration of Z membranes and the focal destruction of I filaments can be observed. After 120 min autolysis further proteolytic products could not be detected by gel electrophoresis but on the electron micrographs the destruction of Z membranes and I filaments became more pronounced. 相似文献
209.
E Somogyi I Balogh G Rubányi P Sótonyi L Szegedi 《The American journal of forensic medicine and pathology》1981,2(1):31-39
The pathomechanism of carbon monoxide (CO) poisoning was studied by means of cardiopathological and neuropathological investigations in experimental CO intoxication. It has been shown that besides CO-hemoglobin association, the binding of CO to cytochromes is a significant factor. The latter is thought to be responsible for the cytotoxic phenomena. Combined ultrastructural and cytochemical studies have enabled differentiation between toxic, hypoxic, and mixed alternations. 相似文献
210.