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Rashid Khan Ashwani K Singal Bhupinderjit S Anand 《World journal of gastroenterology : WJG》2014,20(34):11935-11938
Alcohol abuse and chronic hepatitis C virus(HCV)infection are two major causes of chronic liver disease in the United States.About 10%-15%of liver transplants performed in the United States are for patients with cirrhosis due to combined alcohol and HCV infection.Data on outcomes on graft and patient survival,HCV recurrence,and relapse of alcohol use comparing transplants in hepatitis C positive drinkers compared to alcohol abuse or hepatitis C alone are conflicting in the literature.Some studies report a slightly better overall outcome in patients who were transplanted for alcoholic cirrhosis vs those transplanted for HCV alone or for combined HCV and alcohol related cirrhosis.However,some other studies do not support these observations.However,most studies are limited to a retrospective design or small sample size.Larger prospective multicenter studies are needed to better define the outcomes in hepatitis C drinkers. 相似文献
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GEMMA PELARGONIO MARIA L. NARDUCCI ELEONORA RUSSO MICHELA CASELLA PASQUALE SANTANGELI ROBERT CANBY AMIN AL‐AHMAD LARRY D. PRICE LUIGI DI BIASE CANDICE J. KWARK MARK HARWOOD FRANCESCO PERNA GIANLUIGI BENCARDINO CAROLINA IERARDI ENRICO M. TRECARICHI ENRICA SANTELLI MARIO TUMBARELLO PRASANT MOHANTY SHANE BAILEY JOHN DAVID BURKHARDT FULVIO BELLOCCI ANDREA NATALE ANTONIO DELLO RUSSO 《Journal of cardiovascular electrophysiology》2012,23(10):1103-1108
Transvenous Lead Extraction . Introduction: As the population ages, the number of elderly patients with implantable cardiac devices referred for transvenous lead extraction will dramatically increase in Western countries. The safety and effectiveness of lead extraction in elderly patients has not been well evaluated. We report the safety and effectiveness of transvenous lead extraction in octogenarians. Methods and Results: From January 2005 to January 2011, we reviewed data from consecutive patients ≥ 80 years referred to our institutions for transvenous lead extraction because of cardiac device infection or lead malfunction. Clinical characteristics, procedural features, and periprocedural major and minor complications were compared between octogenarians and younger patients. Out of 849 patients undergoing lead extraction in the participating institutions during the study period, 150 (18%) patients were octogenarians (mean age 84 years; range 80–96; 64% males). A significantly higher percentage of octogenarians presented with chronic renal failure (55% vs 26%; P < 0.001), history of malignancy (22% vs 6%; P < 0.001), and chronic obstructive pulmonary disease (46% vs 19%; P < 0.001). Complete lead extraction rates were similar in the 2 age groups (97% in octogenarians vs 96% in patients <80 years; P = 0.39). Periprocedural death occurred in 2 (1.3%) patients ≥80 years and in 5 (0.72%) patients <80 years (P = 0.45 for comparison). No differences in terms of other periprocedural major and minor complications were found between the 2 age groups. Conclusion: Despite presenting with a significantly higher rate of comorbidities, transvenous lead extraction can be performed safely and successfully in octogenarians. (J Cardiovasc Electrophysiol, Vol. 23 pp. 1103‐1108, October 2012) 相似文献
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Percutaneous balloon aortic valvotomy was attempted in six consecutiveadolescents and young adults, (meanage 18 ± 5 years),with severe congenital aortic valvular stenosis. Peak systolicaortic valve gradient measurement and aortography was performedbefore and immediately after valvotomy, and a 16 monthsfollow-up. The single-balloon technique was used in two patientsand the double-balloon technique in four patients. After balloonvalvotomy the mean peak systolic aortic valve gradient (PSG)decreased from 122 ± 53 to 43 ± 20 mmHg (P >001). The haemodynamic improvement persisted at follow-up (PSG= 47 ±31 mmHg), except in one patient who had previouslyundergone aortic surgical valvotomy. One balloon valvotomy wasunsuccessful, presumably because of the selection of an inappropriatelysmall balloon. Two patients with critical aortic stenosis (PSG>165mmHg), who exhibited a thick aortic valve on echocardiographywith a relatively small aortic root and annulus, had a dramaticreduction in PSG. However, the degree of aortic regurgitationincreased significantly in both cases. The theoretical haemodynamicadvantage of the double versus the single balloon techniqueswas confirmed in one patient. We have demonstrated that percutaneousballoon aortic valvotomy using either the single- or double-balloontechnique is feasible in young adults with severe congenitalaortic stenosis. Further studies are required both to defineappropriate patients and the selection of balloon diameter andlength. 相似文献
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Translational regulation of the L11 ribosomal protein operon of Escherichia coli: analysis of the mRNA target site using oligonucleotide-directed mutagenesis. 总被引:8,自引:1,他引:8 下载免费PDF全文
G Baughman M Nomura 《Proceedings of the National Academy of Sciences of the United States of America》1984,81(17):5389-5393
The L11 ribosomal protein operon in Escherichia coli consists of the genes for proteins L11 and L1 and is feedback regulated by the translational repressor L1. The mRNA target site for this repression is located close to the translation initiation site of the first L11 cistron. Several mutant plasmid molecules carrying altered nucleotide sequences in the L1 target site were constructed by site-directed in vitro mutagenesis using synthetic oligodeoxyribonucleotides. Specifically, we examined the importance of a presumptive double-stranded stem structure that is common among L1 binding sites on rRNA from a variety of organisms and in L11 mRNA. Mutational alterations that disrupt the stem structure were found to abolish translational regulation as analyzed both in vitro and in vivo. Two of the mutations were combined so that the stem structure was restored but with a different primary nucleotide sequence. This double mutant was shown to restore the original phenotype, the ability to be translationally regulated by L1. These experiments show the importance of the stem structure, but not its primary sequence, for the interaction of L1 with the mRNA and support the concept that mRNA target sites share some structural features with the corresponding ribosomal protein binding sites of rRNA. 相似文献
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Yousra H. AL JAZAIRY Hassan Suliman HALAWANY Nawaf AL HUSSAINAN Nassr AL MAFLEHI Nimmi Biju ABRAHAM Vimal JACOB 《Industrial health》2014,52(4):324-333
A disparity exists in the educational qualifications of dental assistants working in
various public and private institutions in Riyadh, Saudi Arabia. The aim of this study was
to assess the influence of professional and personal characteristics on job satisfaction
among dental assistants. A cross-sectional survey was performed among dental assistants
using a 24-item self-administered questionnaire. Multinomial logistic regression was used
to assess the relationship between overall job satisfaction and other variables. The
overall response rate was 72.1%. Factor analysis suggested that five underlying factors
were related to job satisfaction. The mean score for overall job satisfaction was 3.86
(satisfied) out of 5. Among the work environment factors, the highest mean score, 4.26
(satisfied), was obtained for quality of service, and the lowest mean score, 2.78
(neutral), was obtained for the perception of income. The income and general prospects of
the profession was significantly associated with overall job satisfaction. This study
suggests that for dental assistants, professional and personal life, quality of service,
perception of income and prestige and self-respect are important factors for job
satisfaction. Despite differences in professional formation standards, in general, the
study participants were considerably satisfied with their jobs. 相似文献