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901.
Over the past decade, the proliferation of election surveys has worked to undergird the electoral system in Mexico and to make electoral fraud more difficult. In the presidential elections of 1994, significant controversies arose as to survey methodologies, but by the congressional elections of 1997 the fierce debates over methodologies had subsided. Substantively, the surveys confirm the accuracy of the vote count in 1998, allow profiles of voters to be constructed for the three most important parties and mark declines in the support of the once dominant Partido Revolucionario Institucional.  相似文献   
902.
The number of deaths as a consequence of orphenadine poisoning seems to increase, mostly among severely psychotic males. The lethal dose corresponds to the weekly average dose used in the treatment of neuroleptic extrapyramidal side effects. Based on the literature, the serious, rapidly incipient, cardiac, and neurologic symptoms of poisoning are emphasized. The handing out of orphenadine to suicidal persons must be restricted, and even small overdoses (1-2 g) ought to result in the immediate initiation of observation at an intensive care unit.  相似文献   
903.
904.
When infants die suddenly of acute dehydration, clinical signs and autopsy findings may be equivocal or absent, and microbiologic cultures often are not helpful. Vitreous humor electrolyte and urea nitrogen concentrations were measured in 53 infants dying of gastrointestinal infections, sudden infant death syndrome (SIDS), other infectious diseases, and miscellaneous causes to determine whether these parameters would assist in the recognition and confirmation of deaths resulting from dehydration. Significant differences were found when comparing the mean sodium and urea nitrogen levels of infants dying of gastrointestinal infections with those succumbing to SIDS or other causes. We recommend that these determinations be routinely performed whenever the gross autopsy findings are insufficient to explain the death.  相似文献   
905.
906.
External beam proton-induced X-ray emission (PIXE) analysis has been used to verify the presence of lead in the finger bone of a murder victim. The deceased, who had been buried several years, was known to have suffered a bullet wound to his right hand several years before death. X-ray radiographs of the right second proximal phalanx revealed the possible presence of metal fragments below the surface of the bone. To verify the presence of lead in a nondestructive manner, the bone was scanned with a 1.5-MeV proton beam. PIXE analysis showed that lead was present only in the vicinity of the fragments previously detected in the radiographs. A study of gunshot residue in bone shows that the distribution of lead around the bullet hole is independent of the firing distance for distances greater than 0.6 m.  相似文献   
907.
This study examined the effects of anonymity on jurors' verdicts and on jurors' feelings of accountability for their jury's verdicts. Twenty four-person anonymous juries and 20 four-person nonanonymous juries rendered individual and group verdicts for three student defendants charged with selling drugs on a school campus. When unanimous guilty verdicts were reached, juries imposed one of five punishments. Finally, jurors completed postdeliberation opinion and accountability questionnaires. As predicted, anonymous juries showed a higher rate of conviction (70%) than did nonanonymous juries (40%) when the evidence against the defendant was strong, supporting the hypothesis that anonymity would have a greater effect for situations in which there was relatively strong evidence of the defendant's guilt. Anonymous juries imposed the harshest punishment (expulsion) significantly more often than did nonanonymous juries. Contrary to predictions from differential self-awareness theory, anonymous juries did not report feeling less accountable than did nonanonymous juries. However, anonymous juries did see the process as significantly more fair than did identifiable juries.  相似文献   
908.
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   
909.
910.
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