Résumé
Objective To investigate the relationship of the intensity of Schistosoma japonicum infection with the variation in individual egg counts. Methods Stool specimens were collected from residents in a village in Jiangxi Province and examined with Kato-Katz thick smear method for seven consecutive days. Two smears were prepared and microscopically examined for each specimen. 570 individuals completed the investigation. Coefficient of variation (CV) was used to assess the intra-individual variation of the egg counts, in relation to the demographic characteristics including age,sex,occupation,and the intensity of infection. Results The proportion of individuals with at least one positive finding increased from 33.0% in a single measurement to 56.5% by seven measurements (P0.05). Conclusion The prevalence and intensity of S. japonicum infection by single Kato-Katz test was obviously lower than the real figures. The intensity of infection may be an essential factor that affects the intra-individual variation of egg counts.
Résumé
Objective To study the effect of di-n-butyl phthalate (DBP) on the development of Oregon K Drosophila melanogaster. Methods Drosophila melanogasters were divided randomly into four groups and were continuously fed with the medium containing 0, 0.2%, 0.6%, 1.8% DBP respectively during entire trial period. The growth and the development of filial generation drosophilas were observed. Results Compared with the control, the eclosion periods of filial generation drosophilas in DBP groups were significant longer(P