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951.
952.
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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In general, individuals who first received social security retired-worker benefits in June 1980-May 1981 viewed themselves as being in good health. They reported this view in response to questions in the 1982 New Beneficiary Survey conducted by the Social Security Administration. Two-thirds of the respondents in the retired-worker sample reported having no health-related work limitations and no moderate or severe functional activity limitations. However, more than half of those who did report such limitations indicated that the limitations were severe enough to keep them from any work for pay. Beneficiaries whose first monthly benefits were claimed at age 62 were more likely to report themselves in poor health than those receiving a first benefit at age 63 or older, but even among the 62-year-olds, more than three-fifths reported no work-limiting conditions.  相似文献   
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