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991.
992.
Capillary electrophoresis, the modern approach to instrumental electrophoresis, is probably the most rapidly expanding analytical technique that has appeared in recent years. In the hands of forensic toxicologists, capillary electrophoresis (CE) represents a powerful new analytical tool, which has proved suitable for the investigation of illicit drugs in seized preparations and also in complex biological matrices, among which is hair. CE can be applied according to different separation mechanisms, and among those that are toxicologically relevant are capillary zone electrophoresis and micellar electrokinetic capillary chromatography, which display different selectivities. For the investigation of hair for drugs of abuse, capillary electrophoresis proved effective, providing simultaneous determinations of different drugs without derivatization, with acceptable sensitivity (typically better than 1 ng of drug per mg of hair). The possibility of carrying out determinations of the same analytes, based on different separation mechanisms (capillary zone electrophoresis and micellar electrokinetic chromatography) with the same instrumentation, simply changing the buffer composition, provides an interesting possibility of ‘internal’ confirmation of the results.  相似文献   
993.
This paper argues that the central concepts of justice theory (e.g., inputs and outcomes) have not been well defined and that this lack of precision in definition has led to subsequent ostensible inconsistencies in empirical findings. We offer definitions of both inputs and outcomes in a manner that facilitates more formal theoretical formulations and specifies a functional relationship between the two. In addition, the concept of relevance is discussed. This discussion highlights the difference in determinations of what is relevant to an outcome and the moral desirability of the distribution rule producing those outcomes. We suggest that the perception of what is relevant to the production of an outcome and how much it should be weighted is a source of potential conflict and/or disagreement between groups who are allocators or recipients of resource distributions. The potential disjuncture between what is considered relevant and what is considered moral in terms of allocation decisions is a potential source of dissatisfaction and feelings of injustice across groups. The discussion also suggests that it is not simply a difference in rule preference across groups that may lead to negative feelings regarding allocations but even when groups agree on the rule they may not agree on either the factors to be included in the assessment of relevance or on the morality of the distribution resulting from such assessments. Finally we introduce the concept of exchange domain as a mechanism for facilitating theoretical development.  相似文献   
994.
995.
In a further study of the addiction-crime relationship, 214 narcotic addicts were classified according to their criminal involvement during a 2-year preaddiction period. The sample was divided into two groups—those who reported involvement in any of 20 categories of criminal activity (N = 108) and those who reported no such activity (N = 106). The criminal behavior and drug-use patterns of the two groups were then compared during subsequent addiction and nonaddiction periods. As expected, the impact of addiction was much more prominent in the low-crime group. The implications of results for rehabilitation strategies are discussed.  相似文献   
996.
Postmortem stability of DNA   总被引:11,自引:0,他引:11  
High-molecular-weight DNA was recovered postmortem in sufficient quantities from various human organ tissues as well as from blood, although not all organs were equally well suitable. Good DNA stability was found in brain cortex, lymph nodes and psoas muscle over a period of three weeks postmortem. Spleen and kidney showed good DNA stability up to five days postmortem but after longer periods, rapid degradation was observed. Yields of DNA from blood were not consistent because of the non homogeneity of samples. Blood clots were rich with DNA. Generally, the amount of degraded DNA correlated directly with the duration of the postmortem period. However in some cases, DNA degradation was already prominent after a short period. However in some cases, DNA degradation was already prominent after a short period. Case histories showed that high environmental temperature at the site of death and/or infectious diseases prior to death were the main factors for rapid autolysis. Gradual disappearance to complete loss of the long fragments (15-23 kb) was observed in DNA fingerprinting using the minisatellite probe 33.15. No extra-bands were noted, thus excluding erroneous conclusions. However, evidentiary value of older samples was lower.  相似文献   
997.
998.
Empirical evidence is collected and discussed regarding the influence of public bureaucrats on government sector outcome in their capacity as consumer-voters. It is necessary to isolate the specific effect of working in the public sector (compared to other occupations) on voting participation and on the probability to support an increase in the public budget. For a balanced evaluation of public bureaucrats' power, other forms of their influencing the government sector outcome need to be taken into account.  相似文献   
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