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The seasonal distribution of cryptosporidiosis in children in Aragón, a region in northeastern Spain, was determined. Over a period of six years (October 1988 to September 1994), 10,034 stool samples from 4,508 children with gastrointestinal symptoms were analyzed for this purpose. The age of the patients ranged from 1 month to 14 years. Cryptosporidium oocysts were identified in 87 (1.93%) patients. Prevalence was highest (6.20%) in children aged 1 to 3 years old. The prevalence was significantly higher in the autumn-winter period (October to March) than in the spring-summer period (April to September) in the whole population (2.41% vs. 1.35%, p = 0.010) and in the 1- to 3-year-old age group (8.44% vs. 3.20%, p = 0.002), but not in the other age groups. A possible relationship of this pattern to attendance at child care centres is suggested. 相似文献
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Spore cortex of conditional cortexless mutants of Bacillus sphaericus 9602 was not detectable by electron microscopy unless the medium was supplemented with meso-alpha,epsilon-diaminopimelic acid during sporulation. Other spore structures appeared normal. Spore shape was quite irregular in the absence of meso-alpha,epsilon-diaminopimelic acid. 相似文献
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