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113.
This paper discusses the organization of the first international proficiency test (PT) programme on ketamine (K) and norketamine (NK) in hair samples. The primary objective of the programme was to evaluate the analytical capability of participating laboratories on hair analysis for K and NK via comparison of results. Authentic samples, instead of spiked samples were used in the programme to mimic the analysis of incorporated illicit drugs in real-life situations. Eight of the ten participating medical or forensic laboratories from Australia, France, Hong Kong, Italy, Singapore and the USA returned results to the organizer. Quantification methods from these laboratories were confined to GC-MS and LC-MS/MS. Performance assessment based on z-score indicated that only three laboratories achieved satisfactory results for both the analysis of K and NK. It was concluded that the overall performance of the participating laboratories was fair and there is still room for further improvement. Additional similarly designed PT programmes are recommended to be organized in order to encourage reliable measurements of illicit drugs in hair samples. Taking into account the substantial effect on the consensus values within limited number of data points, a recommendation on the provision of reference values assigned by accurate methods will be of benefit to small size PT programmes in the forensic field. 相似文献
114.
Umbilical cord blood is a source of haematopoietic progenitor cells, which are used to treat a range of malignant, genetic, metabolic and immune disorders. Until recently, cord blood was either collected through donations to publicly funded cord blood banks for use in allogeneic transplantation, or stored in commercial cord blood banks for use in autologous transplantation. The line between public and private cord blood banking is being blurred by the emergence of "hybrid" models that combine aspects of both the public and private systems. The authors describe these hybrid models and argue that their emergence is explained by both market forces and public sector policy They propose that the future of the sector will depend heavily on several key developments that will differentially affect public, private and hybrid banking models. 相似文献
115.
Komesaroff PA Kerridge IH Stewart C Samuel G Lipworth W Jordens CF 《Journal of law and medicine》2012,19(3):517-524
While direction of donated tissue to family members has long been accepted, direction to members of specific racial groups has been opposed, on the basis that it is discriminatory and contrary to the ethos the institution of organ donation seeks to promote. It has, however, recently been proposed that racially conditional donation may provide a useful--and ethically acceptable--way to address the social inequalities and injustices experienced by certain cultural groups. This article examines the ethical, legal and cultural arguments for and against racially conditional donation, concluding that the practice is more likely to undermine the values of equity and justice than to promote them and that it may also lead to other unfavourable personal and social outcomes. 相似文献
116.
While Western observers typically attribute the population's nationalist anti-Americanism largely to government propaganda or manipulation, they misunderstand the roots of anti-American behavior in China. As depicted by Peter Hay Gries in China's New Nationalism and by Michael H. Hunt in The Genesis of China's Foreign Policy, a more nuanced portrayal is in order. While the two books utilize distinct socialpsychological and historical perspectives, an integrative reading of the two suggests that popular expression is in fact largely responsible for China's anti-Americanism. At first this conclusion in favor of popular expression may seem at odds with Hunt's state-centered analysis of the roots of foreign policy. Nevertheless, after a brief summary of each book and a comparative application to the issue of anti-Americanism, the authors demonstrate that applying a comparative historical reappraisal to Hunt's study suggests that both scholarly works support the predominant role of popular expression on contemporary China's nationalist anti- Americanism. 相似文献
117.
Samuel Stoljar 《The Journal of legal history》2013,34(2):250-269
118.
This study examines the longitudinal effects of childhood community contexts on young adult outcomes. The study uses a sample
of 14,000 adolescents (52% female) derived from the 1990 US Census and the National Longitudinal Study of Adolescent Health
(Addhealth). The study examines whether community and family environments exert separate and/or joint long-term influences
on young adult achievement and depression. We found both direct and indirect long-term influences of childhood community adversity
on young adult educational attainment. The indirect influences of childhood community adversity operated through family and
individual-level factors. The long-term influence of childhood community adversity on young adult depression was only indirect.
Overall, community influences on young adult achievement outcomes were mediated by family context and by the adolescents’
adjustments and transitions, including adolescent depression, school adjustment, and disruptive transitional events. The moderating
effect of childhood community adversity suggests that the protective effects of family resources on young adult outcomes dissipate
significantly in extremely adverse neighborhoods. The findings demonstrate the importance of integrating multiple theoretical
perspectives for longitudinal research to capture pathways of community influence on adolescent developmental and young adulthood
outcomes. 相似文献
119.
Samuel Nunn 《Journal of policy analysis and management》1994,13(3):539-559
Mobile digital terminals (MDTs) are two-way computers, installed inside police vehicles, that provide officers with remote data base prospecting capabilities. Proponents argue that MDTs help officers recover stolen property. Several Texas police departments implemented MDT systems in the 1980s. This article assesses how MDTs in Dallas and Fort Worth affected vehicle theft recoveries, in comparison to a city with no MDTs, Austin. Five hypotheses are evaluated in a multiple interrupted time series design using ANOVA, response surface analysis, and pooled time series regression. The analysis of recoveries before and after intervention in two MDT cities and one non-MDT control city suggests that the technology is linked with increases in vehicle theft recoveries. The magnitude of improvement in recoveries associated with MDTs is more significant at lower levels of vehicle thefts. Austin showed some improvement in recovery rates without using MDTs, so other factors besides the technology are likely to be important. 相似文献
120.
Simultaneous separation of different types of amphetamine and piperazine designer drugs by capillary electrophoresis with a chiral selector 总被引:1,自引:0,他引:1
Bishop SC McCord BR Gratz SR Loeliger JR Witkowski MR 《Journal of forensic sciences》2005,50(2):326-335
The recent emergence of a new class of piperazine-type compounds has brought about the need for laboratory screening methods for both seized drugs and toxicological samples. These piperazine compounds, which include 1-benzylpiperazine (BZP) and 1-(3-trifluoromethylphenyl)piperazine (TFMPP), exhibit comparable physiological effects and can be substituted for the classic amphetamine-type drugs. We have optimized a chiral capillary electrophoresis (CE) separation that detects a set of 6 piperazine and 4 chiral amphetamine compounds in under 23 min using a 200 mM phosphate buffer at a pH = 2.8 with 20 mM hydroxypropyl- beta-cyclodextrin (HPbeta3CD). In addition to the above compounds, a series of "clandestine" BZP diHCl samples were also analyzed using this method to assess the ruggedness of the procedure. The novel CE separation was tailored to simultaneously detect these piperzine compounds in addition to amphetamine-type drugs. Distinct migration time and UV-spectral data were obtained for all compounds of interest. 相似文献