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AIM: This exploratory pilot study developed and tested the validity of picture cards as a strategy to ascertain patients' desired participation in decision making. These were then used to ascertain characteristics of Hong Kong Chinese patients' decision-making preferences for surgery. VALIDATION OF TOOL: Two sets of analyses tested the validity of picture cards in an Australian and Hong Kong Chinese population. First, the ratings of the two groups of participants using the picture cards for three scenarios (severe, moderate and mild medical conditions) were correlated with mean ratings of three decision-making subscales of a self-report questionnaire for the three scenarios. Second, a 3 (Scenario) x 2 (Ethnic Group) mixed anova examined whether the picture cards are sensitive to differences relating to severity of medical conditions and ethnicity. SETTING AND PARTICIPANTS: A convenience sample of initially 35 Hong Kong and 24 Australian patients was used to validate the picture card tool. A convenience sample of a further 186 Hong Kong Chinese surgical inpatients used the tool. DESIGN: Participants selected the picture card that best represented their decision-making preference. MAIN VARIABLES: Demographic factors, prior knowledge, nature of surgery and preference for participation in decision making. RESULTS: Significant correlations were made between the questionnaire and the picture card tool. Using the tool, a significant difference was found between males' and females' decision-making preference, yet, no significant difference was found with respect to type or previous surgical operation.  相似文献   
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This study investigated the relationship in human placenta between polycyclic aromatic hydrocabon (PAH)-DNA adduct levels and two biomarkers of cytochrome P4501A1 (CYP1A1): gene induction evidenced by CYP1A1 mRNA, and a genetic polymorphism, the CYP1A1 MspI RFLP. CYP1A1 codes for an inducible enzyme system that catalyzes the bioactivation of PAHs. Prior research found a high correlation in human lung tissue between CYP1A1 activity and DNA damage from PAHs. The CYP1A1 Mspi RFLP has been linked in some studies to risk of lung cancer. The relationships in human placenta between DNA damage, CYP1A1 activity and genotype have not been well characterized and may be relevant to risks from transplacental PAH exposure. The study cohort consisted of 70 newborns from Krakow, Poland, a city with elevated air pollution, and 90 newborns from nearby Limanowa, an area with lower air pollution but greater indoor coal use. Contrary to results seen previously in lung tissue, CYP1A1 mRNA was not significantly correlated with PAH-DNA adduct levels in the placenta. Smoking (self-reported maternal and infant plasma cotinine) was significantly associated with CYP1A1 mRNA levels (P < 0.01), but not with PAH-DNA adduct levels. Placental PAH- DNA adduct levels were significantly higher in infants with the CYP1A1 MspI restriction site compared with infants without the restriction site (P < 0.01), implicating a genetic factor in inter-individual variation in DNA damage in human placenta. Further studies are needed to determine the relevance of this finding to risk of transplacental carcinogenesis.   相似文献   
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Several lines of evidence indicated that P cell-stimulating factor (PSF), a T lymphocyte-derived lymphokine known to stimulate the growth of hemopoietic stem and progenitor cells, also acted on macrophages. PSF was absorbed from medium that had been mixed for two hours at 0 degrees C with either resident or thioglycollate-elicited peritoneal cells, suggesting the presence of receptors for PSF on cells in the population. The addition of pure PSF to populations highly enriched in either resident or elicited adherent peritoneal macrophages resulted in stimulation of macrophages with morphological changes, including increases in size, spreading, vacuolation, and the number of cytoplasmic processes, together with stimulation of proliferation and the phagocytosis of opsonized yeast. PSF also stimulated the incorporation of [3H]thymidine by bone marrow-derived adherent macrophages. Addition of pure PSF to cultures that contained only a single macrophage resulted in enhanced survival and proliferation of these isolated cells, demonstrating that the effect of PSF on macrophages was direct. These results indicate that PSF can stimulate well-differentiated functional macrophages and raise the possibility that the effects of PSF on macrophages may play a regulatory role in immune responses.  相似文献   
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