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851.
852.
GHB can be produced either as a pre- or postmortem artifact. The authors describe two cases in which GHB was detected and discuss the problem of determining the role of GHB in each case. In both cases, NaF-preserved blood and urine were analyzed using gas chromatography. The first decedent, a known methamphetamine abuser, had GHB concentrations similar to those observed with subanesthetic doses (femoral blood, 159 microg/ml; urine, 1100 microg/ml). Myocardial fibrosis, in the pattern associated with stimulant abuse, was also evident. The second decedent had a normal heart but higher concentrations of GHB (femoral blood, 1.4 mg/ml; right heart, 1.1 mg/ml; urine, 6.0 mg/ml). Blood cocaine and MDMA levels were 420 and 730 ng/ml, respectively. Both decedents had been drinking and were in a postabsorptive state, with blood to vitreous ratios of less than 0.90. If NaF is not used as a preservative, GHB is produced as an artifact. Therefore, the mere demonstration of GHB does not prove causality or even necessarily that GHB was ingested. Blood and urine GHB concentrations in case 1 can be produced by a therapeutic dose of 100 mg, and myocardial fibrosis may have had more to do with the cause of death than GHB. The history in case 2 is consistent with the substantial GHB ingestion, but other drugs, including ethanol, were also detected. Ethanol interferes with GHB metabolism, preventing GHB breakdown, raising blood concentrations, and making respiratory arrest more likely. Combined investigational, autopsy, and toxicology data suggest that GHB was the cause of death in case 2 but not case 1. Given the recent discovery that postmortem GHB production occurs even in stored antemortem blood samples (provided they were preserved with citrate) and the earlier observations that de novo GHB production in urine does not occur, it is unwise to draw any inferences about causality unless (1) blood and urine are both analyzed and found to be elevated; (2) blood is collected in NaF-containing tubes; and (3) a detailed case history is obtained.  相似文献   
853.
854.
In hanging and ligature strangulation, the noose mostly causes a mark or groove which is formed partly by compression of the skin and partly by abrasion with loss of the upper epidermal layers. The horny scales abraded from the neck may be transferred to the strangulation device or to the interposed textiles where they are sometimes visible at stereomicroscopic examination or even to the naked eye as silver-grey particles. The morphologic features of the epidermal transfer due to hanging and ligature strangulation is demonstrated by 14 case examples. The biological traces may be sufficient for comparative DNA typing by means of PCR-based methods. In 9 out of the 14 cases, genomic DNA typing was successful. Analysis of mtDNA succeeded in another two cases, although genomic DNA could not be detected. Beside the accumulation of solid epidermic particles the paper describes deposition of serous and fatty tissue fluid at the ligature (mainly adjacent to skin ridges).  相似文献   
855.
856.
The 4-methylaminorex (4-MAX) is an amphetamine-related psychostimulant drug that has appeared on the clandestine market with a street name of "U4Euh". This compound exists as four stereoisomers, trans-4R,5R, trans-4S,5S, cis-4R,5S and cis-4S,5R, of which the cis forms have been classified as Schedule I substances in the US. The increasing variety of designer drugs has highlighted the importance of detection, identification, and quantitative measurement of these drugs, including 4-MAX, in biological samples. In the present study, the isomers of 4-MAX were detected in urine of rats treated with the drugs by some but not all of the on-site immunoassays tested, mainly as amphetamine or methamphetamine. To facilitate identification of 4-MAX by laboratories specialized in drug analysis, the electron-ionization mass spectrum and TLC data for underivatized 4-MAX using a routine laboratory drug-screening procedure is provided. In addition, a GC/MS method is described for the quantitative determination of cis- and trans-4-MAX as tert-butyldimethylsilyl-derivatives in plasma, urine and tissue.  相似文献   
857.
This paper addresses research in the life sciences, responsible for significant national expenditures for scientific investigations funded by both the federal government and industry. Our investigation examines faculty members' involvement with industry in entrepreneurial ways that is, involved in translating their research into potentially marketable knowledge or products. First, this study examines whether there are differences in entrepreneurial behaviour between clinical and non-clinical faculty in the life sciences with industry relationships, and, second, to discover any linkage between entrepreneurship and secrecy or productivity in different ways for clinical and non-clinical faculty. The study is based on survey responses of a national sample of 4,000 clinical and non-clinical life sciences faculty in 49 U.S. research universities. The results show non-clinical faculty as more involved at the back end. The more entrepreneurial end of commercialization while clinical faculty are involved at the back end. The more entrepreneurial faculty (non-clinical) are more likely to be secretive about their research. Clinical faculty are less likely to have been denied access to research results or products. Entrepreneurial faculty are not less productive in their faculty roles. This investigation is preliminary in that it addresses one large area of academic research but excludes fields with longer historical relationships with industry.  相似文献   
858.
859.
挤压综合征大鼠血清酶浓度变化的初步研究   总被引:1,自引:1,他引:0  
Liu SP  Chen YC  Guo W  Cheng JD 《法医学杂志》2001,17(4):205-206
目的观察挤压伤大鼠血清肌酸激酶(CK)、肌酸激酶心肌同功酶(CK-MB)浓度的变化,阐明肢体挤压伤大鼠早期是否存在心脏损伤。方法复制挤压伤大鼠动物模型,全自动生化分析仪检测血清CK、CK-MB浓度的变化。结果挤压伤后12h,血清CK、CK-MB浓度显著升高,并持续48h以上。结论肢体挤压伤早期可能有心脏损伤的存在。  相似文献   
860.
Less than half of all children who receive Supplemental Security Income (SSI) benefits and live in a single-parent home receive child support services. Although filing for child support is a condition of eligibility for income assistance programs such as Temporary Assistance for Needy Families (TANF), it is not a condition of eligibility for SSI benefits. Requiring single custodial parents applying for SSI on behalf of their children to pursue child support payments might result in more children on SSI receiving child support, and since the Social Security Administration (SSA) excludes one-third of child support when determining benefit amounts, increased receipt of child support would enhance the financial well-being of SSI children. Improving access to data on child support would enhance the integrity of the SSI program by reducing overpayments to children receiving child support. This article looks at the child support provisions in SSI and other means-tested programs and discusses policy options for improving receipt of child support and access to related data. Requiring cooperation with child support enforcement agencies would be consistent with the philosophy that the SSI program should serve as a program of last resort. Whenever possible, both parents should take primary responsibility for their children. While such a requirement has the potential to improve the financial status of children receiving SSI, factors such as their low-income status and their involvement with the TANF program raise questions about how much those children will actually benefit from such a requirement. Even if many additional children do not receive child support, the requirement demonstrates SSA's dedication to the stewardship of the SSI program. However, if custodial parents fail to comply with the requirement, children may be worse off as a result of the requirement. SSA should carefully pursue a requirement to induce cooperation while protecting children to the greatest extent possible. Improving access to child support data would enhance the integrity of the SSI program by reducing overpayments to children receiving child support. Given the reality of limited administrative resources as well as the apparent difficulties of gaining access to the needed child support data, SSA must decide which data matches to pursue and which requirements enhance the program enough to justify the additional resources. Although the options discussed in this article may be chosen independently, there are important interactions to consider. For example, although a requirement to pursue support might result in more children receiving child support, SSA would still rely on parents to report that income unless it was able to gain better access to child support data. Implementing the option to require cooperation with child support enforcement (CSE) agencies could improve verification of income from child support if field offices developed better communication with local CSE offices. However, by itself, it would not have as great an effect on overpayments as would having direct access to child support data. In a 1999 report, the General Accounting Office acknowledged that the potential benefit reductions would be offset by the cost for SSA to administer a child support cooperation requirement and by the costs to the CSE programs to provide services. The report suggested that the goals of promoting parental responsibility and increasing the income of children receiving SSI should be pursued despite the costs. Requiring cooperation may increase administrative costs by $6 million over 5 years and may result in program savings. Gaining access to data may be more expensive and may not prevent overpayments to the same extent as other data-matching workloads on which SSA has placed a priority. SSA should continue to work with federal child support enforcement and with individual states to develop a cost-effective way to identify child support income.  相似文献   
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