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排序方式: 共有867条查询结果,搜索用时 15 毫秒
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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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Increase of intracellular Ca2+ and relocation of E-cadherin during experimental decompaction of mouse embryos 下载免费PDF全文
Roxana Pey Clarisa Vial Gerald Schatten Mathias Hafner 《Proceedings of the National Academy of Sciences of the United States of America》1998,95(22):12977-12982
To determine the role of intracellular Ca2+ in compaction, the first morphogenetic event in embryogenesis, we analyzed preimplantation mouse embryos under several decompacting conditions, including depletion of extracellular Ca2+, blocking of Ca2+ channels, and inhibition of microfilaments, calmodulin, and intracellular Ca2+ release. Those treatments induced decompaction of mouse morulae and simultaneously induced changes in cytosolic free Ca2+ concentration and deregionalization of E-cadherin and fodrin. When morulae were allowed to recompact, the location of both proteins recovered. In contrast, actin did not change its cortical location with compaction nor with decompaction-recompaction. Calmodulin localized in areas opposite to cell–cell contacts in eight-cell stage embryos before and after compaction. Inhibition of calmodulin with trifluoperazine induced its delocalization while morulae decompacted. A nonspecific rise of intracellular free Ca2+ provoked by ionomycin did not affect the compacted shape. Moreover, the same decompacting treatments when applied to uncompacted embryos did not produce any change in intracellular Ca2+. Our results demonstrate that in preimplantation mouse embryos experimentally induced stage-specific changes of cell shape are accompanied by changes of intracellular free Ca2+ and redistribution of the cytoskeleton-related proteins E-cadherin, fodrin, and calmodulin. We conclude that intracellular Ca2+ specifically is involved in compaction and probably regulates the function and localization of cytoskeleton elements. 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
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Iman Amy Betawi Sinaria Kamil Abdel Jabbar Mohammad. A. AL Jabery Haidar Ibrahim Zaza Muhannad Al-Shboul 《Early child development and care》2014,184(12):1992-2003
This study examined fathers' perceptions regarding their home-based activities (HBA) and the influence of fathers' demographic characteristics on their perceptions and practices at home. A total of 396 fathers completed a survey questionnaire describing their demographic information, perceptions and their practices regarding their involvement in HBA. Results indicated that fathers have moderate level of practice concerning their HBA, yet they have low perception of their actual practice at HBA. In addition, there was a statistical significance in HBA due to fathers' age, educational level and specialisation which had an influence on their perceptions as well. Recommendations and implications of future research were discussed. 相似文献
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