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941.
Abstract: A 15‐year‐old male orally consumed an unknown but fatal amount of sustained release hydromorphone. He was naïve to opioid use. No other drugs or alcohol were involved. The cause of death was acute aspiration‐related bronchopneumonia, secondary to hydromorphone ingestion; the manner of death was accidental. Hydromorphone and hydromorphone‐3‐glucuronide were quantified in postmortem fluids by tandem liquid chromatography–mass spectrometry. The hydromorphone concentrations in the peripheral blood, urine, and vitreous humor were 57, 4460, and 31 ng/mL, respectively. The hydromorphone‐3‐glucuronide concentrations in the corresponding three fluids were 459, 36,400, and 40 ng/mL. Hydromorphone‐3‐glucuronide accumulation probably did not contribute significantly to the opiate toxicity. The proposed minimum lethal hydromorphone blood concentration in the nontolerant user is in the vicinity of 60 ng/mL. 相似文献
942.
A gas chromatography-negative ion chemical ionization tandem mass spectrometric (GC-NCI-MS/MS) method was developed and validated for the determination of 11-nor-Δ(9)-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) in human hair. After decontamination, hair samples were weighed (25mg), mechanically pulverized with a bead mill, and incubated in 0.7 mL of 1.0M sodium hydroxide at 95 °C for 30 min. Bead-assisted liquid-liquid extraction was performed with n-hexane:ethyl acetate (9:1, v/v), a method developed in our laboratory. The extract was evaporated to dryness, derivatized with pentafluoropropanol and pentafluoropropionic anhydride, and analyzed by GC-MS/MS in the negative ion chemical ionization mode using methane as the reagent gas. The linear ranges were 0.05-10.0 pg/mg for THC-COOH with the coefficient of determination (r(2) = 0.9976). The intra-day and inter-day precisions were within 1.7 and 13.8%, respectively. The intra-day and inter-day accuracies were -4.8 to 10.0% and -3.9 to 3.8%, respectively. The limit of detection and quantification were 0.015 and 0.05 pg/mg, respectively. The recoveries were in the range of 79.4-87.1%. The results indicate that the proposed method is simple, rapid, accurate, and precise for determination of THC-COOH in hair. The method identified THC-COOH in hair specimens from suspected marijuana abusers. 相似文献
943.
The study was carried out to investigate external contamination of hair by blood in heroin-related post-mortem cases. Solutions were prepared containing 0.05, 0.1, 0.2, 0.5 and 3.0μg/mL of 6-monoacetylmorphine (6-AM) only or morphine only in human blood. Samples of approximately 3.2g of drug-free hair were contaminated by soaking in the blood solutions for 5min. They were then removed and left at room temperature. Approximately 0.5g of hair was collected from each of the blood soaked hair samples at 6h, 1, 2, 4 and 7 days after contamination. As each hair sample was collected it was shampoo-washed to prevent further drug absorption. Hair samples were analysed in triplicate using a fully validated method described previously. 6-AM broke down to morphine in all samples. In hair contaminated with blood containing 0.05, 0.1 and 0.2μg/mL 6-AM or morphine drug was either not detected or was detected below the limit of quantitation (0.2ng/mg hair) at all contamination times. In hair contaminated with blood spiked with 0.5μg/mL morphine, the concentration in hair ranged from 0.54 to 0.91ng/mg and in hair contaminated with blood spiked with 3.0μg/mL, from 3.25 to 5.77ng/mg. The concentrations of 6-AM ranged from 0.65 to 1.11ng/mg and morphine from 0.34 to 0.80ng/mg in hair contaminated with 0.5μg/mL 6-AM in blood. 6-AM ranged from 2.12 to 3.67ng/mg and morphine from 0.84 to 2.05ng/mg in hair contaminated with 3μg/mL 6-AM in blood. For 6-AM and morphine ANOVA statistical evaluation showed no significant difference among the concentrations over time. 相似文献
944.
Han E Yang W Lee S Kim E In S Choi H Lee S Chung H Song JM 《Forensic science international》2011,206(1-3):e85-e92
The quantitative analysis of 11-nor-D(9)-tetrahydrocannabinol-9-carboxylic acid (THCCOOH) in hair requires a sensitive method to detect a low-pg level. Before applying the method to real hair samples, the method was validated; in this study, we examined the uncertainty obtained from around the cut-off level of THCCOOH in hair. We calculated the measurement uncertainty (MU) of THCCOOH in hair as follows: specification of the measurand, identification of parameters using "cause and effect" diagrams, quantification of the uncertainty contributions using three factors, the uncertainty of weighing the hair sample, the uncertainty from calibrators and the calibration curve, and the uncertainty of the method precision. Finally, we calculated the degrees of freedom and the expanded uncertainty (EU). The concentration of THCCOOH in the hair sample with its EU was (0.60 ± 0.1) × 10(-4)ng/mg. The relative uncertainty percent for the measurand 0.60 × 10(-4)ng was 9.13%. In this study, we also selected different concentrations of THCCOOH in real hair samples and then calculated the EU, the relative standard uncertainty (RSU) of the concentration of THCCOOH in the test sample [u(r)(c0)], the relative uncertainty percent, and the effective degree of freedom (v(eff)). When the concentrations of THCCOOH approached the cut-off level, u(r)(c0) and the relative uncertainty percent increased but absolute EU and v(eff) decreased. 相似文献
945.
In this study, we investigated the patterns of cannabis users (n=412) according to their sex, age, and the results of urinalysis and hair analysis, and classified the concentrations of THCCOOH in hair into three categories to examine the levels of cannabis use. We also compared the concentrations of THCCOOH in hair root, hair without the hair root and whole hair and examined the relationship among them according to the results of urinalysis. The hair samples were washed, digested with 1ml of 1M NaOH at 85°C for 30min and extracted with 2ml of n-hexane:ethyl acetate (9:1) two times after adding 1ml of 0.1N sodium acetate buffer (pH 4.5) and 200μl of acetic acid. The final mixture was derivatized with 50μl of PFPA and 25μl of PFPOH for 30min at 70°C. The solution was evaporated, and the residue was reconstituted in 40μl of ethyl acetate and transferred to an autosampler vial. One microlitre was injected into the GC/MS/MS-NCI system. The concentrations of THCCOOH ranged from 0.06 to 33.44pg/mg (mean 2.96; median 1.32) in hair from cannabis users who had positive urine results and ranged from 0.05 to 7.24pg/mg (mean 1.35; median 0.37) in hair from cannabis users who had negative urine results. The average concentration of THCCOOH in hair from cannabis users who had positive urine results was higher than that from cannabis users who had negative urine results. Male cannabis users in their forties were predominant. We classified the concentrations of THCCOOH in hair into three groups (low, medium and high), and could use the grouping of THCCOOH in hair as a guide for determining the level of use. The low, medium and high concentration ranges for THCCOOH in hair were 0.05-0.24, 0.25-2.60 and 2.63-33.44pg/mg, respectively. We also investigated 28 hair samples with the root. The highest concentrations of THCCOOH were seen in the hair root from 18 out of the 28 hair samples. The average concentrations of THCCOOH in hair root, hair without hair root and whole hair from cannabis users who had positive urine results were higher than those who had negative urine results. 相似文献
946.
Lee PR Estes CL 《The Annals of the American Academy of Political and Social Science》1983,(468):88-102
The making of health policy in the United States is a complex process that involves the private and public sectors, including multiple levels of government. Five characteristics of the policy process are identified, which establish the means by which policies are formulated and which affect the nature of the policies that emerge. These characteristics include (1) the relationship of the government to the private sector; (2) the distribution of authority and responsibility within a federal system of government; (3) the relationship between policy formation and implementation; (4) a pluralistic ideology as the basis of politics; and (5) incrementalism as the strategy for reform. The article focuses on the impact on health policy of the distribution of authority and responsibility within the federal system, particularly the impact of new federalism policies as they emerged during the past decade. The effects of dual federalism, cooperative federalism, creative federalism, and new federalism are examined in relation to health policies. The article concludes with an examination of the challenge to long-established values and health policies posed by new federalism. 相似文献
947.
The frequency distributions of eight STR loci were surveyed in 510 unrelated individuals from the Korean population 相似文献
948.
High resolution Y chromosome typing: 19 STRs amplified in three multiplex reactions 总被引:26,自引:0,他引:26
Bosch E Lee AC Calafell F Arroyo E Henneman P de Knijff P Jobling MA 《Forensic science international》2002,125(1):42-51
Nineteen Y-specific short tandem repeat (STR) loci have been amplified in 768 samples from the Iberian Peninsula in order to evaluate their usefulness in forensic casework. Two previously published multiplex reactions by Thomas et al. [Hum. Genet. 6 (1999) 577] (MS1, modified here: DYS19, DYS388, DYS390, DYS391, DYS392 and DYS393) and by Ayub et al. [Nucl. Acids Res. 28 (2000) e8] (CTS: DYS434, DYS435, DYS436, DYS437, DYS438 and DYS439) plus a novel one reported here (EBF: DYS385, DYS389, DYS460, DYS461, DYS462 and amelogenin) have been used. DYS385, DYS439 and DYS391 were the most informative loci with allele diversities of 0.7997, 0.6683 and 0.5940, respectively. A total of 635 different haplotypes were observed, of which 573 (90.24%) were found in single individuals. The overall haplotype diversity was 0.9988 and that obtained by each multiplex system was 0.9812 for EBF, 0.9292 for MS1 and 0.9089 for CTS. 相似文献
949.
Although numerous studies document the effect of political institutions on foreign direct investment (FDI), few works in the political economy literature have investigated the link between political institutions and the mode of entry chosen by investors, be it mergers and acquisitions, joint ventures, or greenfield investments. Using panel data for 111 developing countries covering 1980–2006, we find that countries with political institutions that uphold good governance tend to attract higher levels of mergers and acquisitions, as opposed to joint ventures and greenfield investments, because such institutions help to mitigate the special risks faced by merger and acquisition investors. Our findings provide a nuance for understanding the different effects of political institutions based on the particular mode of entry. 相似文献
950.
Frank Lee Cantrell Pharm.D. Patricia Ogera M.D. Phyllis Mallett B.S. Iain M. McIntyre Ph.D. 《Journal of forensic sciences》2014,59(3):847-849
Methylphenidate (MPD) is a widely prescribed stimulant used primarily for the treatment for attention‐deficit/hyperactivity disorder (ADHD). Suicide attempts involving MPD ingestion have been well described; however, deaths attributed solely to MPD ingestion have not been reported. A 62‐year‐old woman was found dead on her floor. The only discrepancy in among her medication quantities was that >three hundred 10 mg MPD tablets were missing. Analysis utilizing gas chromatography–mass spectrometry revealed elevated postmortem MPD peripheral and central blood, liver and vitreous humor concentrations. Considering both the central blood to peripheral blood ratio (0.89) and the liver to peripheral blood ratio (3.3), MPD does not appear subject to significant postmortem redistribution. With no other identifiable cause of death, we report what appears to be the first isolated MPD ingestion associated with a fatality. 相似文献