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81.
82.
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
83.
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
84.
Y. K. Ng 《Social Choice and Welfare》1989,6(2):87-101
Individual preferences inconsistent with personal welfare caused neither by ignorance nor by a positive consideration for the welfare of others are defined as (welfare) irrational. Sources of irrationality (rigid adherence to moral principles, excessive fear of danger, excessive tempetation of pleasure, revenge, inertia, faulty telescopic faculty, the fallacy of diminishing marginal utility of utility, etc.) are discussed. An evolutionary explanation of irrationality is suggested and some implications for individual decision and social policy indicated.I am grateful to two anonymous referees for comments. 相似文献
85.
The expanding knowledge and skill bases within the interdisciplinary family therapy profession pose a significant challenge for evolving practitioners, at whatever stage along the professional development process they find themselves. This challenge raises a basic question regarding whether there are any constraining forces to the level of eclecticism in practice towards which one can aspire. This paper empirically explores the role played by the personality attributes of the family therapist in facilitating and/or inhibiting one's adherence to a variety of approaches to family practice. 相似文献
86.
Breunlin DC Schwartz RC Krause MS Kochalka J Puetz RA Dyke J 《Journal of marital and family therapy》1989,15(4):387-395
Research on family therapy training has produced very little data regarding the kinds of trainees that do best in family therapy training programs. This study attempts to provide some rough and preliminary data on that issue. One hundred and seventy trainees, drawn from seven different structural!strategic training experiences, were evaluated as to how much they learned by taking the Family Therapy Assessment Exercise pre- and posttraining. Their performance was correlated using a hierarchical regression analysis with a number of trainee variables such as amount of conjugal family experience, amount of experience doing family or individual therapy, or prior knowledge of family therapy. The results indicate that, as predicted, conjugal family experience was positively related, and prior knowledge was negatively related to performance. Prior experience doing individual therapy was also positively related to performance. 相似文献
87.
Roberts J Matthews WJ Bodin NA Cohen D Lewandowski L Novo J Pumilia J Willis C 《Journal of marital and family therapy》1989,15(4):397-410
Working with a treatment and observing team at the same time, behind the oneway mirror, offers a variety of ways to: (a) generate multiple realities; (b) work with two different models of family therapy simultaneously; and (c) provide feedback on the teams' own roles, rules and group process. The process that 6 trainees and two supervisors used with T and O teams to examine their own coevolution as a therapeutic system using the Milan model of family therapy and Ericksonian hypnotherapy is described. The article concludes with a discussion of the advantages and pitfalls of this type of dual supervision. 相似文献
88.
An estimated 200,000-500,000 men, women, and children work in prostitution in the Philippines in a variety of venues, including brothels, nightclubs, pubs, massage parlors, and other legitimate entertainment establishments. Few, however, are voluntary prostitutes. Many people who work as prostitutes have been recruited from the provinces, kept in conditions similar to slavery, and forced to earn money from prostitution to pay for their transportation, board, and lodging. Many prostitutes work in urban centers and tourist resorts in the countryside. During the 1970s, then President Ferdinand Marcos promoted tourism as a major industry, effectively marketing attractive Filipinas to tourists. Sex tourism has flourished in the country ever since. Thousands of prostitutes are also located in Olongapo and Angeles, 2 cities north of Manila, from where they serve the sexual desires of US military personnel. The presence of US military personnel in the Philippines has always been associated with prostitution. The country's social hygiene centers, prostitutes in Manila and Davao, and AIDS education are briefly discussed. 相似文献
89.
G C Polk 《Journal of psychosocial nursing and mental health services》1989,27(4):24-27
The internalization of clinical nursing research values, norms, and attitudes via orientation and research development, along with the introduction of research tools (artifacts), constitutes the birthing phase of the acculturation process. The development of unit and individual research agendas and the implementation of research rounds illustrates a "bonding phase," in that nurses are bonding or weaving research into the fabric of their clinical practice. The final phase, stabilization, occurs when clinical nursing research is core to clinical nursing practice as illustrated by rewards or sanctions via performance evaluations, and provisions for release time for research participation. 相似文献
90.
Oheneba-sakyi Y 《Sociological perspectives : SP : official publication of the Pacific Sociological Association》1989,32(4):485-500
A comparison of cohorts of ever-married Chanaian women suggests evidence of a fertility transition beginning among younger women and select subgroups. Ghana's crude birth rate declined from a high of 50/1000 population in 1970 to 38.8/1000 in 1985. To ascertain whether marital fertility is now being controlled through conscious attempts to lengthen birth intervals, World Fertility Survey data from 1979-80 on the timing of births among different birth cohorts were analyzed. It was hypothesized that, as a result of the influence of Western values that stress independence from parents and the introduction of compulsory education, cohorts of the mid-1950s and 1960s would be more likely to postpone childbearing, more active in the modern sector of the economy, and more accepting of modern contraceptive usage for birth spacing than women in the 1930-39, 1940-49, and 1950-59 cohorts. For the 1940-49 cohort, it took 10.8 months for 25% to have a birth following 1st marriage, 18.7 months for 50% to have a 1st birth, and 27.4 months for 75% to complete this step. By comparison, these figures for the 1955-64 birth cohort were 9.9, 16.7, and 20.5 months, respectively. The significantly shorter (p 0.01) interval between marriage and 1st birth found among younger women in part reflects rising age at marriage; mean age at 1st marriage was 17.9 years for the 1940 cohort and 21.6 years for the most recent cohort. After the birth of the 1st child, recent cohorts were more likely to wait longer for the 2nd birth. For women born in 1950-64, it took 21.8, 36.7, and 44.6 months for 25%, 50%, and 75%, respectively, to reach parity 2. This pattern of lengthened birth interval beyond the 1st birth was apparent at all parities in the youngest cohort and indicates increasing acceptance of contraception among those who have come of age during a period of rapid social change. 相似文献