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For traditionally underserved populations, the Web can potentially unlock resources that could fundamentally improve health and wellbeing. However, there are many barriers to using Web-based content. While physical access issues are well documented, there is little understanding of how nonmainstream populations use or will use the Web. Based on an ethnographic study of a group of low-literate adults, we have identified specific navigational and content issues that present barriers to this population. We discuss preliminary assumptions that can be used to inform the development of Web tools for this target audience, and directions for future applied research.  相似文献   
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BACKGROUND: There is irrefutable evidence of the association between lung cancer and smoking. The effects of public health campaigns to reduce population-smoking rates on the incidence and the histological distribution of lung cancer were examined. METHODS: The data held in the New South Wales Cancer Registry from 1972 to 2001 was accessed. RESULTS: The data revealed a decreasing incidence of lung cancer amongst males and a rate that continued to increase amongst females. Interestingly, there was also an effect on the histological distribution of lung cancers, with falling rates of small cell lung cancer and squamous cell cancer, both of which have a high association with smoking; and an increasing incidence of adenocarcinomas. CONCLUSIONS: These trends reveal patterns seen worldwide. The increasing proportion of adenocarcinomas in particular may be related to the changing composition of cigarettes and filters.  相似文献   
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BACKGROUND: Sublingual buprenorphine is used as a substitution drug in heroin addicts. Although buprenorphine inhibits mitochondrial function at high concentrations in experimental animals, these effects should not occur after therapeutic sublingual doses, which give very low plasma concentrations. CASE REPORTS: We report four cases of former heroin addicts infected with hepatitis C virus and placed on substitution therapy with buprenorphine. These patients exhibited a marked increase in serum alanine amino transferase (30-, 37-, 13- and 50-times the upper limit of normal, respectively) after injecting buprenorphine intravenously and three of them also became jaundiced. Interruption of buprenorphine injections was associated with prompt recovery, even though two of these patients continued buprenorphine by the sublingual route. A fifth patient carrying the hepatitis C and human immunodeficiency viruses, developed jaundice and asterixis with panlobular liver necrosis and microvesicular steatosis after using sublingual buprenorphine and small doses of paracetamol and aspirin. CONCLUSIONS: Although buprenorphine hepatitis is most uncommon even after intravenous misuse, addicts placed on buprenorphine substitution should be repeatedly warned not to use it intravenously. Higher drug concentrations could trigger hepatitis in a few intravenous users, possibly those whose mitochondrial function is already impaired by viral infections and other factors.  相似文献   
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The effect of taurocholate on transcytotic vesicular pathways labeled with horseradish peroxidase was assessed in isolated perfused rat liver preparations. Forty-five minutes after a horseradish peroxidase load in a recirculating system, continuous infusion of taurocholate but not taurodehydrocholate significantly increased horseradish peroxidase excretion in bile by 50% compared with controls. When horseradish peroxidase (25 mg) was pulse loaded for 1 minute in control perfusions, it appeared in bile in early (4-6 minutes) and late (20-25 minutes) peaks, the latter accounting for 90% of total horseradish peroxidase output. Taurocholate infusion significantly increased horseradish peroxidase output in both early and late peaks, whereas only a small increase in the early peak was observed with taurodehydrocholate. Colchicine pretreatment increased the early peak in bile but abolished the second peak. Electron micrographs from control livers revealed the accumulation of horseradish peroxidase-containing vesicles in pericanalicular regions at early (2 minutes) as well as late (18 minutes) periods. When a morphometric analysis of electron micrographs was performed from pericanalicular regions 2 minutes after a 1-minute pulse of horseradish peroxidase (500 mg), taurocholate but not taurodehydrocholate increased both the density and percent area of horseradish peroxidase-containing vesicles compared with controls. In contrast, colchicine pretreatment had no effect on the density of the early-appearing vesicles, although their individual sizes were reduced. Taurocholate but not taurodehydrocholate also increased the percent of tubular structures in the pericanalicular region. These findings indicate that taurocholate stimulates both early and late transcytotic vesicle pathways and therefore probably microtubule-independent vesicle pathway is present in hepatocytes that must be distinguished from paracellular routes.  相似文献   
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