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81.
Simian virus 40 large tumor antigen-immortalized normal human liver epithelial cells express hepatocyte characteristics and metabolize chemical carcinogens. 总被引:9,自引:2,他引:9
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A M Pfeifer K E Cole D T Smoot A Weston J D Groopman P G Shields J M Vignaud M Juillerat M M Lipsky B F Trump et al. 《Proceedings of the National Academy of Sciences of the United States of America》1993,90(11):5123-5127
Normal human liver tissue and cultured human hepatocytes are valuable models to study xenobiotic metabolism and toxicity, but they only have a limited in vitro life-span and are not readily available. This report describes the establishment of replicative cultures of human adult liver epithelial cells in serum-free medium. The longevity of three of these cultures, derived from different donors, was extended by introduction of the simian virus 40 large T antigen gene. Two cell lines, THLE-2 and -3, established with a recombinant simian virus 40 large T antigen virus have undergone > 100 population doublings, are nontumorigenic when injected into athymic nude mice, have near-diploid karyotypes, and do not express alpha-fetoprotein. The cells express cytokeratin 18 and albumin in early passage, whereas higher-passage cells in logarithmic-phase growth also express cytokeratin 19. THLE-2 and -3 cells metabolize benzo[a]pyrene, N-nitrosodimethylamine, and aflatoxin B1 to their ultimate carcinogenic metabolites that adduct DNA, which indicates functional cytochrome P450 pathways. Other enzymes involved in metabolism of chemical carcinogens, such as epoxide hydrolase, NADPH cytochrome P450 reductase, superoxide dismutase, catalase, glutathione S-transferases, and glutathione peroxidase are also retained by THLE cells. Thus, these immortalized human liver cells constitute an in vitro model for pharmacotoxicological studies and for the investigation of etiology and pathogenesis of human hepatocellular carcinoma. 相似文献
82.
Repair of erosions in rheumatoid arthritis does occur. Results from 2 studies by the OMERACT Subcommittee on Healing of Erosions 总被引:4,自引:0,他引:4
Sharp JT Van Der Heijde D Boers M Boonen A Bruynesteyn K Emery P Genant HK Herborn G Jurik A Lassere M McQueen F Østergaard M Peterfy C Rau R Strand V Wassenberg S Weissman B;Subcommittee on Healing of Erosions of the OMERACT Imaging Committee 《The Journal of rheumatology》2003,30(5):1102-1107
The committee was charged with determining whether healing of erosions in rheumatoid arthritis (RA) occurs. Two exercises were performed: The first asked the committee members, as a panel of experts, to express agreement or disagreement with the presence of improvement and features of bone reaction to injury in images submitted by members as examples of healing. The second presented panel members with 28 pairs of serial images, 14 chosen to illustrate progression and 14 chosen to illustrate repair. Agreement was tested on 8 items: global judgment on which image in the pair was better, relative size of the erosion in the 2 images, judgment on which image was first, presence and extent of sclerosis, cortication, filling-in, remodeling, and reconstituting normal structure. Our results showed good agreement, among the 15 respondents, on global assessment of which image was better and which image showed the smaller erosion. Correct assignment of sequence was only slightly better than expected by chance (in 65% of the cases). Agreement was poor regarding the presence of morphologic features of bone repair. A majority of a panel of experts agreed on which 2nd images in a set of paired, serial images represented improvement and which showed progression based on global assessment of which was better and on size of erosion. Features of bone repair were not distinctive and did not enable the panel to deduce the correct sequence of the serial images. This study provides evidence that repair of bone damage in RA does occur, resulting in some degree of improvement, which was recognized by a majority of a panel of experts. 相似文献
83.
A female patient with a three year history of Crohn's disease of the colon developed myasthenia gravis. Despite diversion of the faecal stream by an ileostomy, and total colectomy, the patient had continuing problems with perineal and perianal abscesses and fistulas. Her myasthenia gravis became unresponsive to anti-cholinergics so a thymectomy was performed. The perineal and perianal disease improved subsequently. This case supports the theory that functional disturbances of the thymus may have a role in the pathogenesis of inflammatory bowel disease. 相似文献
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Aspects of control and substance use among middle‐aged and older adults with bipolar disorder
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Marissa N. Stalman BSN Sarah L. Canham PhD Atiya Mahmood PhD David King PhD Norm O'Rourke PhD RPsych 《International journal of mental health nursing》2018,27(2):833-840
High prevalence rates of alcohol and substance use disorders have been reported among persons with bipolar disorder (BD). In the present study, we explored the daily experiences of middle‐aged and older adults living with BD who reported regular substance use and the ways in which participants expressed ‘control’ in relation to their use of alcohol and other substances. Semistructured, in‐depth interviews were conducted with 12 participants (nine women and three men), aged 36–57 years of age (mean = 49 years). Thematic analyses identified emergent themes and patterns in participants’ life histories. The theme of ‘control’ emerged as central to participants’ reports, and was organized into four categories: (i) substance use to control BD symptoms; (ii) substance use provides a sense of being in control; (iii) methods of controlled substance use; and (iv) not having control: overreliance on substances. Implications of the present study include the need for nurses to openly discuss the use of alcohol and other drugs with persons with BD, provide health information and screening, and determine whether persons with BD feel they have control over their substance use. Several lines of research with persons who have BD and use substances are suggested. 相似文献
86.
Alison M. Darcy PhD Kathleen Kara Fitzpatrick PhD Stephanie M. Manasse BA Nandini Datta BS Megan Klabunde PhD Danielle Colborn PhD Vandana Aspen PhD Colleen Stiles‐Shields MA MS Zandre Labuschagne MA Daniel Le Grange PhD James Lock MD PhD 《The International journal of eating disorders》2015,48(5):487-493
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Bright I Nwaru Mome Mukherjee Ramyani P Gupta Angela Farr Martin Heaven Andrew Stoddart Amrita Bandyopadhyay Deborah Fitzsimmons Michael Shields Ceri Phillips George Chamberlain Colin Fischbacher Christopher Dibben Chantelle Aftab Colin R Simpson Ronan Lyons David Strachan Gwyneth A Davies Brian McKinstry Aziz Sheikh 《Journal of the Royal Society of Medicine》2015,108(11):433-439
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