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931.
932.
933.
934.
935.
Demographic and trend analysis of 881 consecutive suicides in blacks and whites is presented. For the years 1975 through 1984, the suicide rate was 15.1/100 000 and did not significantly change. White males were overrepresented in all age groups, had an overall suicide rate of 34.9, and showed a small but statistically significant increase in rate which was not accounted for by any specific age group. White females, in general, were represented in proportion to their prevalence in the population, and those ages 20 to 24 demonstrated an increasing suicide rate which was small. Black males were at highest risk in their twenties, showed no significant trends, and were also represented near their prevalence in the population. Black females of all ages were underrepresented, and had low suicide rates which decreased with time. No significant rate changes were noted for teenagers or the elderly. Firearms was the method of choice in all groups, although methods varied with age, race, and sex, and male children preferred hanging. Small but significant increases were noted for the prevalence of nondrug methods in females and carbon monoxide deaths in white males. Similarities and differences to larger scale studies are discussed. Suicide may have characteristics unique to given geographical areas and pervasive to all areas. The authors advocate study and publication of local data to clarify further the nature of suicide.  相似文献   
936.
The effects of carbon monoxide and cyanide on the hepatic redox state and energy charge were investigated. Rats were used for the experiment under pentobarbital anesthesia. Immediately after laparotomy, a rat was placed in an animal chamber made of a transparent plastic box and exposed to a test gas for 3 min. Every test gas was produced in a gas chamber connected to the animal chamber with a flexible tube. HCN was produced from NaCN and H2SO4. In the CO inhalation experiment, various amounts of CO were introduced into the gas chamber. Immediately after an exposure, about 2 g liver was frozen in situ with a precooled clamp. Oozed blood from the wound surface was sampled. Concentrations of ATP, ADP, AMP, acetoacetate, and beta-hydroxybutyrate in hepatic mitochondria were determined, and the redox state and the energy charge were calculated. For cyanide as well as CO, significant negative correlations were found between the concentration in the blood and the redox state. The same held true for the energy charge. The redox state showed a slight increase at low concentrations of both gases; however, thereafter it began to decrease sharply with increases in concentrations. When concentrations of the toxicant in the blood reached certain levels, a kind of turning point, beyond which the redox state does not decrease any more, was observed. It was about 40% for HbCO and about 2.0 micrograms/ml for cyanide, and the points seemed to be related to the concentrations, beyond which cells are irreversibly damaged. On the other hand, the energy charge did not change at low concentrations. With an increase in toxicant concentrations, the energy charge decreased drastically. The rate of decrease in the energy charge became higher when blood concentrations exceeded certain levels. It was about 40% for HbCO and 2.0 micrograms/ml for cyanide. The presence of low levels of blood cyanide did not affect the relationship between the energy charge and the HbCO concentration.  相似文献   
937.
938.
In 53 cases of death - including 12 cases of sudden infant death syndrome (SIDS) - where blood samples could be taken within 18 h postmortem, the thyroxines T4, FT4, T3 and FT3 were determined (ELISA and RIA). These hormone values were compared with the corresponding histological thyroid findings in 43 cases (11 SIDS, 32 controls). Nearly identical T4 and FT4 mean values were found in both groups which were within the norms. In contrast to the average values of the control group, the T3 and FT3 concentrations of the SIDS group showed an increase of 3.7-fold and 1.9-fold. Accordingly, histological examination of the SIDS group showed highly activated and extensively released follicles whereas normal colloidal-containing follicle structures were observed in nearly all control cases. The present findings indicate that neither postmortem T4 T3 conversion nor intensified agonal hormone secretion is likely to be the only cause of the increasing T3 and FT3 values. In SIDS cases chronic or recurring chronic stress situations are supposed to be the cause for the hormonal and histological thyroid findings. Some differential diagnoses are discussed. Within 18 h after death, increased concentrations of T3 and FT3, together with simultaneous colloid release, represent a diagnosis of SIDS.  相似文献   
939.
940.
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   
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