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201.
Lesa L. Aylward Robert C. Brunet Thomas B. Starr Gaétan Carrier Elizabeth Delzell Hong Cheng Colleen Beall 《Risk analysis》2005,25(4):945-956
Recent studies demonstrating a concentration dependence of elimination of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) suggest that previous estimates of exposure for occupationally exposed cohorts may have underestimated actual exposure, resulting in a potential overestimate of the carcinogenic potency of TCDD in humans based on the mortality data for these cohorts. Using a database on U.S. chemical manufacturing workers potentially exposed to TCDD compiled by the National Institute for Occupational Safety and Health (NIOSH), we evaluated the impact of using a concentration- and age-dependent elimination model (CADM) (Aylward et al., 2005) on estimates of serum lipid area under the curve (AUC) for the NIOSH cohort. These data were used previously by Steenland et al. (2001) in combination with a first-order elimination model with an 8.7-year half-life to estimate cumulative serum lipid concentration (equivalent to AUC) for these workers for use in cancer dose-response assessment. Serum lipid TCDD measurements taken in 1988 for a subset of the cohort were combined with the NIOSH job exposure matrix and work histories to estimate dose rates per unit of exposure score. We evaluated the effect of choices in regression model (regression on untransformed vs. ln-transformed data and inclusion of a nonzero regression intercept) as well as the impact of choices of elimination models and parameters on estimated AUCs for the cohort. Central estimates for dose rate parameters derived from the serum-sampled subcohort were applied with the elimination models to time-specific exposure scores for the entire cohort to generate AUC estimates for all cohort members. Use of the CADM resulted in improved model fits to the serum sampling data compared to the first-order models. Dose rates varied by a factor of 50 among different combinations of elimination model, parameter sets, and regression models. Use of a CADM results in increases of up to five-fold in AUC estimates for the more highly exposed members of the cohort compared to estimates obtained using the first-order model with 8.7-year half-life. This degree of variation in the AUC estimates for this cohort would affect substantially the cancer potency estimates derived from the mortality data from this cohort. Such variability and uncertainty in the reconstructed serum lipid AUC estimates for this cohort, depending on elimination model, parameter set, and regression model, have not been described previously and are critical components in evaluating the dose-response data from the occupationally exposed populations. 相似文献
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Ohne Zusammenfassung 相似文献
205.
M. J. Stones Thomas Hadjistavropoulos Holly Tuuko Albert Kozma 《Social indicators research》1995,36(2):129-144
Veenhoven (1994) contrasted hypotheses of whether happiness is a trait or state, concluding that it is a state variable. This article critiques the conceptual foundation of Veenhoven's paper, and examines technical deficiencies in his review of evidence. Based on previous findings and new analyses, we conclude that happiness has both traitlike and statelike properties, but that individual differences in happiness endure despite its situational reactivity, and explain greater variance than situational effects. 相似文献
206.
Tattling on siblings was observed in 40 families with 2- and 4-year-old children. All but 5 children reported sibling misbehaviour to parents with younger siblings tattling largely to recruit parental help in resolving conflict issues, and older siblings tattling both in the context of conflict and merely to inform parents of their siblings' misbehaviour. Parents rarely reprimanded children for tattling, but either ignored it, or responded to information in tattlers' reports regardless of context or whether older or younger children tattled. Children did not tattle equally on all sibling transgressions, but emphasized physical aggression and property damage, issues that also elicited parental discipline. Tattling is discussed in relation to children's understanding of the dynamics and moral standards of family life. 相似文献
207.
Knodel J Wongsith M 《Asian and Pacific population forum / East-West Population Institute, East-West Center》1989,3(4):1-10, 25-35
"Using 1980 census and 1987 survey data on birth cohorts to examine recent primary and secondary school enrollment trends [in Thailand], this study reports that primary enrollment is nearly universal but secondary enrollment is much less prevalent. The study assesses several factors thought to influence enrollment and finds that urban residence, parents' completion of primary school, the mother's positive attitude toward education, and the family's being comfortable economically to be associated with children's enrollment in secondary school. It also indicates that, for moderately well-off families, proximity to schools has a major influence on secondary school attendance. For the wealthiest families, however, distance is not a hindrance to attendance, and for the poorest families, having a school nearby is not sufficient to ensure attendance." 相似文献
208.
Lemoine M 《International migration (Geneva, Switzerland)》1989,27(2):271-279
The recognition of the right to family reunification in 1976 brought far-reaching changes in the characteristics of the foreign population in France. Today, France's immigrant population has the following characteristics: 1) 42.6% are female, 2) 40% are under 25 years of age, and 3) foreigners are increasingly dispersed throughout France. Those with residents' cards may automatically obtain residents' cards for their spouses and children. France's reception policy calls for a social worker to visit a recently arrived family, to assess their need for and to promote social services. Problems of adaptation include 1) wives' social isolation and 2) changes in relations between father and children. The integration policy conducted by public authorities has 4 main aspects: 1) socio-educational activities, 2) cultural activities, 3) vocational training, and 4) activities connected with housing and lifestyle. In 1975, France began offering assisted return procedures to dismissed unskilled workers. In 1984, the authorities introduced public assistance in reintegration for workers under threat of dismissal or who had already been dismissed. The number of foreigners resident in France should remain stable over the next few years, making the integration of immigrant communities within French society a vital task. 相似文献
209.
Passaris C 《International migration (Geneva, Switzerland)》1989,27(4):525-542
This is a review of "the limited and scant contributions made to immigration theory in the context of the evolution of economic thought over a protracted historical time span." The economic theories considered include those of the mercantilists, Adam Smith, the classical economists, and J. M. Keynes. (SUMMARY IN FRE AND SPA) 相似文献
210.
Compliments are often viewed primarily as a linear event in which one person expresses approval or admiration of another. Far less attention has been given to the circular nature of compliments and the manner in which they enhance the positions of both the giver and the receiver of the compliment. Therapeutic compliments have proven to be highly effective means of motivating clients, while at the same time increasing therapeutic leverage. This article proposes that compliments should be purposefully given, and that the type of compliment should vary with the stage of therapy and the intended response of the client to the compliment. 相似文献