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991.
The armamentarium of the forensic thanatologist includes the examiner's subjective assessment of bodily changes together with comprehensive evaluation of environmental and associated factors to estimate the postmortem interval (PMI). Of the various objective means, postmortem accumulation of potassium in vitreous humor is a widely used gauge. In view of the considerable variability inherent in these techniques, an additional marker with greater accuracy would be a welcome supplement to these indices. We have developed a method of estimating PMI from the level of 3-methoxytyramine (3-MT) in the dorsal putamen of the brain. The supernatant of a sample of putamen, sonicated in 6 volumes (weight/volume) of 0.1 M perchloric acid and centrifuged at 51 000 times gravity for 10 min, was analyzed for 3-MT using high-pressure liquid chromatography with electrochemical detection. The change of 3-MT in the putamen is linearly related to the PMI (range: 5.5 to 60 h), irrespective of patient age (1 to 84 years). This observation is attributable to several factors, including high substrate (dopamine) concentration, preservation of catechol-O-methyl transferase activity, and an inactivation of monoamine oxidase activity, as a result of a decrease in tissue pO2.  相似文献   
992.
For the last several centuries, most jurisdictions using capital punishment have had formal or informal rules that prohibit the execution of the mentally ill. In this article, the procedures for such exclusions in Florida are examined. The article begins by attempting to answer the question of why legislators and judges, at least nominally, have prohibited the execution of the mentally ill. Next, Florida's criteria for defining and procedures for excluding mentally ill prisoners are examined and found to be vague. We then turn attention to the ethical problems created by the statute and its implementation that face the participating psychiatrists and the profession. These problems are compounded because the physician's findings are not acted upon by politically neutral authorities and the inmate has no opportunity to challenge the findings with his own panel of experts. Finally, since any exclusion of the mentally ill from execution is temporary and the patient will be executed if he recovers, the dilemmas facing the treatment staff if the death sentence is not commuted to life imprisonment before treatment are discussed.  相似文献   
993.
冯友兰是中国近现代史上著名的哲学家和哲学史家。他从中国文化和中国社会发展方向的前提出发,比较中西文化之间的差异,形成了关于文化问题和社会发展问题的一系列观点。他所提出的以“文化类型”说、“继往开来”说和“道统新续”说为内容的“文化三说”观,对于妥善处理中西文化冲突与融合过程中的时代性和民族性的关系,以及如何弘扬中国传统文化的精华与吸收外国文化的长处等问题,仍然具有积极的现实启迪意义。  相似文献   
994.
995.
In July 2005, the Little Rock, Arkansas, school district implemented a new policy to reorganize its management structure in order to create a more efficient bureaucracy. Using Richard Matland’s ambiguity‐conflict model of policy implementation, the authors examine the implementation of this school reorganization policy. Interviews and surveys were conducted with the superintendent and his executive assistants, school principals, teachers, and staff. In line with Matland’s model, the findings suggest that successful implementation is directly related to the policy characteristics of ambiguity and conflict. However, the authors point to the importance of recognizing particular characteristics for different groups of stakeholders within the policy implementation process. Discrepancies among groups of policy actors in the degree of policy ambiguity and policy conflict lead to strikingly different implementation strategies.  相似文献   
996.
Chloroquine concentrations in blood and tissues were examined in overdose and non-overdose cases to determine appropriate ranges for interpretation. Twenty-nine literature overdose cases and 8 non-overdose literature cases were compared with this laboratory's findings. The results indicate significant postmortem redistribution of chloroquine. Combining this laboratory's results and the literature results indicates that using a liver concentration of 150 mg/kg as a cutoff between overdose and non-overdose concentrations properly identified 30 of the 34 published cases containing liver chloroquine and 19 of the 20 presented cases.  相似文献   
997.
A simple and rapid method for the isolation of seven synthetic pyrethroid insecticides (methothrin, fenpropathrin, cyhalothrin, permethrin, cypermethrin, fenvalerate, deltamethrin) with a solid phase extraction (SPE), utilizing Sep-Pak C18 cartridges, from human urine and plasma is presented. The detection of the insecticides was performed using a wide bore capillary gas chromatograph (GC) with flame ionization detection (FID). The insecticide-containing samples mixed with 70% methanol were directly applied to the cartridges and eluted with 2 ml chloroform. The recoveries using the cartridges were between 90-102% for urine and 81-93% for plasma. Mixing samples with 70% methanol prior to extraction, seems very useful for the screening of synthetic pyrethroid insecticides.  相似文献   
998.
A technique is described for the typing of glyoxalase I (GLO I) and the subtyping of phosphoglucomutase-1 (PGM-1) from the root sheath cells of a single forcibly removed hair. This procedure does not require sample preparation and does not alter the morphological characteristics of the hair. The combined discrimination probability (DP) of the two markers taken together is 0.90 for whites and 0.89 for blacks. GLO I can be typed after four weeks, and PGM-1 can be typed after eight to fifteen weeks in hairs maintained at room temperature. Hairs mounted with Permount showed loss of enzyme activity and loss of band sharpness.  相似文献   
999.
Do we know the lethal dose of cocaine?   总被引:1,自引:0,他引:1  
  相似文献   
1000.
We examine the degree to which parties act as procedural coalitions in Congress by testing predictions from the party cartel theory (Cox and McCubbins 1993, 1994, 2002). We gain leverage on the question of party influence in Congress by focusing on three types of House members: reelection seekers, higher‐office seekers, and retiring members. We argue that retiring House members are no longer susceptible to party pressure, making them the perfect means (when compared to higher‐office seekers and reelection seekers) to determine the existence of party influence. Results from a pooled, cross‐sectional analysis of the 94th through 105th Congresses (1975–98) suggest that party influence is indeed present in Congress, especially where the party cartel theory predicts: on procedural, rather than final‐passage, votes. Moreover, we find that procedural party influence is almost exclusively the domain of the majority party. This latter finding is especially important because most prior studies have been limited to investigating interparty influence only.  相似文献   
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