https://www.selleckchem.com/screening-libraries.html 3%), five large duct iCCAs (17.2%), 10 Comb (16.4%) and 13 HCC (33.3%), respectively (P>0.05). Small duct iCCAs showed altered expression of ARID1A (46.4%), p53 (39.3%), PBRM1 (14.3%), IMP3 (85.7%) and EZH2 (82.1%), whereas these markers were negative in bile duct adenomas. Bile duct adenomas may be precursor lesions of small duct iCCAs. Alteration of ARID1A, p53 or PBRM1 may be involved in the carcinogenesis of small duct iCCAs. Bile duct adenomas may be precursor lesions of small duct iCCAs. Alteration of ARID1A, p53 or PBRM1 may be involved in the carcinogenesis of small duct iCCAs. There have been substantial recent changes in youth tobacco product use in the United States-including, notably, a rapid increase in use of e-cigarettes. It is not known whether, and if so how far, these changes are reflected in levels of nicotine dependence. This study used data from a large, nationally representative sample of US adolescents to (i) estimate the annual prevalence of nicotine dependence in relation to current use of tobacco products, (ii) describe trends in dependence over time and (iii) evaluate whether the increase in youth use of tobacco products has been paralleled by a similar increase in the population burden of nicotine dependence. Secondary analysis of National Youth Tobacco Surveys conducted annually, 2012-19. United States. A total of 86 902 high school students. Prevalence of (i) strong cravings to use tobacco in the past 30days and (ii) wanting to use nicotine products within 30minutes of waking, in relation to type of product used (cigarettes, other combustible tobacco,o have been accompanied by a similar increase in the population burden of nicotine dependence. This may be at least partly attributable to a shift in the most common product of choice from cigarettes (on which users are most dependent) to e-cigarettes (on which users are least dependent). Among US high school students, increases in the pr