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In recent years in Atlanta, homicide has been the most common cause of death in males 20–40 years of age. To study homicide trends in this city we analyzed data for 591 resident victims of criminal homicide in two time perid. 1961–1962 and 1971–1972. Large increases occurred in the homicide rates for both black and white residents. In both races, these rate increases could be accounted for almost entirely by homicides involving firearms Homicide rates for black and whites in 1971–1972 were highest in census tracts with low indices of socioeconomic status; this association was found only for homicides in which the victim and assailant were relatives or acquaintances. There was little geographic overlap between areas with high rates of homicide in the home and high numbers of homicides in public. Using population-based rates facilitates comparisons of homicide occurrence between time periods and/or places.  相似文献   
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Of the fifty-seven cases of cot death studied two-thirds were younger than 3 months, which is also the peak age of infantile hypoglycaemia. Findings from routine necropsy and histology were scarce; in eleven cases they could be regarded as potentially fatal. About half of the infants had had a mild virus-type infection approximately one week before death. Special attention was paid to endocrine pancreas. Insulitis or lymphocytes in the septa were discovered in twelve cases. Hyperplasia of the islets of Langerhans was a common observation; the hyperplasia being either nesidioblastosis-like with clusters of islets around ducti, or diffuse. The average proportion of islet tissue in the whole pancreas parenchyma was around 5% in infants aged 1–6 months, the percentage being significantly greater than in age-matched controls (4.3%). The pancreatic insulin content was also higher in the cot death cases. Serum insulin values were low (mean 4.8 ± 1.2 μU/ml) in cot deaths; in the controls they were twice as high (mean 11.6 ± 1.6 μU/ml) (p < 0.005). The cause of death in this group of cot deaths could thus be (congenital?) hyperplasia of the islets, possibly combined with a lesion in the B-cells caused by a virus. The mechanism of death would be hypoglycaemia.  相似文献   
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