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BACKGROUND: Gallstones and obesity have been suggested as risk factors for cancer of the biliary tract. Since both factors are related to diet, we studied the relationship between dietary intake and the cancer of interest in a population-based case-control study. METHODS: The study population comprised 111 patients and 480 controls. Food intake was assessed by means of a semiquantitative food frequency questionnaire. Estimates of the intake of foods and micronutrients were obtained from cases and controls themselves (direct respondents) or from relatives (indirect respondents). Participants were categorized into tertiles of intake. Risk ratios were estimated by logistic regression analysis. RESULTS: The major findings are a monotonic decrease in risk associated with the consumption of vegetables (ORs 1.0, 0.7, 0.4, P value trend < 0.01) and a monotonic increase in risk associated with sugar added to drinks and desserts (ORs 1.0, 1.3, 2.5; P value trend < 0.01). CONCLUSIONS: The finding on added sugar corresponds to our earlier report that the group monosaccharides and disaccharides is a potential risk factor for this cancer. Sugar may influence bile composition through lipoprotein metabolism. The protective effect of vegetables is in accordance with the reported inverse relationship between vegetables and many epithelial cancers of the alimentary tract.  相似文献   
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The rôle of saponins in the undesirable sensory properties of the dried pea P sativum is reported. The sensory properties of isolated soyasaponin I are defined and described as bitter, astringent and metallic. The distribution of saponin in various air-classified pea flour fractions shows that the protein-rich fraction may contain sufficient saponin to cause undesirable tastes.  相似文献   
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BACKGROUND: It has been suggested that excessive formation of nitric oxide (NO) is responsible for the hyperdynamic circulation observed in portal hypertension. Substance P is a neuropeptide partly cleared by the liver and causes vasodilatation through the activation of the endothelial NO pathway. However, there are no previously published data concerning the plasma level of substance P in cirrhotic rats and its relationship to NO. METHODS: Plasma concentrations of substance P and nitrate/nitrite (an index of NO production) were determined in control rats and cirrhotic rats with or without ascites using an enzyme-linked immununosorbent assay and a colorimetric assay, respectively. In addition, systemic and portal hemodynamics were evaluated by a thermodilution technique and catheterization. RESULTS: Cirrhotic rats with and without ascites had a lower systemic vascular resistance (2.6 +/- 0.2 and 3.9 +/- 0.4 mmHg ml(-1) x min x 100 g body weight, respectively) and higher portal pressure (14.6 +/- 0.6 and 11.3 +/- 1.8 mmHg) than control rats (6.5 +/- 0.3 mmHg x ml(-1) x min x 100 g BW and 6.8 +/- 0.2 mmHg, respectively, P < 0.05), and cirrhotic rats with ascites had the lowest systemic vascular resistance. Plasma levels of nitrate/nitrite progressively increased in relation to the severity of liver dysfunction (control rats, 2.7 +/- 0.5 nmol/ml; cirrhotic rats without ascites, 5.6 +/- 1.3 nmol/ml; cirrhotic rats with ascites, 8.3 +/- 2.2 nmol/ml; P < 0.05). Cirrhotic rats with ascites displayed higher plasma values of substance P (57.7 +/- 5.9 pg/ml) than cirrhotic rats without ascites (37.9 +/- 3.1 pg/ml, P < 0.05) and control rats (30.1 +/- 1.0 pg/ml, P < 0.05). There was no significant difference in plasma substance P values between control rats and cirrhotic rats without ascites (P > 0.05). No correlation was found between plasma levels of substance P and nitrate/nitrite (r = 0.318, P > 0.05). CONCLUSIONS: Excessive formation of NO may be responsible, at least partly, for the hemodynamic derangements in cirrhosis. Although substance P may not participate in the initiation of a hyperdynamic circulation in cirrhosis, it may contribute to the maintenance of the hyperdynamic circulation observed in cirrhotic rats with ascites.  相似文献   
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To determine level of alcohol use/misuse and to examine correlates of these behaviors, 1,314 fourth-grade students were surveyed. The questionnaire included 55 items concerning tolerance of deviance, deviant self-image, self-efficacy, susceptibility to peer pressure, personal and peer approval of alcohol use, peer adjustment, parent nurturance and monitoring, family adjustment, parental permissiveness, peer use of alcohol, and exposure to alcohol. The items were factor analyzed and indices constructed. The indices generally had acceptable alpha coefficients (alpha = .61-.91); two exceptions were peer adjustment (alpha = .51) and parental permissiveness (alpha = .42). Tolerance of deviance, deviant self-image, susceptibility to peer pressure, personal and peer approval, peer use and exposure by peers, and parental permissiveness were positively correlated with alcohol use/misuse. Self-efficacy, child-parent interactions, family adjustment, and peer adjustment were negatively correlated with alcohol use/misuse. Implications for the design of family-based alcohol use/misuse prevention programs are discussed.  相似文献   
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