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101.
S W Werns M J Shea A Vaporciyan S Phan G D Abrams A J Buda B Pitt B R Lucchesi 《Journal of the American College of Cardiology》1987,9(4):898-902
Previous studies demonstrated that treatment with superoxide dismutase, a scavenger of superoxide anions, limits the extent of myocardial injury in a canine preparation of regional myocardial ischemia and reperfusion. Little is known, however, about the effects of superoxide dismutase on the healing of a myocardial infarct. Therefore, this study was performed to determine whether treatment with superoxide dismutase during myocardial ischemia impairs formation of scar tissue after infarction. Dogs received 2 hour infusions of superoxide dismutase or albumin (controls) by way of the left atrium beginning 15 minutes before and ending 15 minutes after a 90 minute occlusion of the left circumflex coronary artery. Six weeks later the animals were killed. Two-dimensional echocardiography was performed before surgery and before induced death. Wall thickening in the central ischemic zone was decreased at 6 weeks compared with baseline studies (p less than 0.05), but the decrease was similar for both groups. The hydroxyproline concentrations (microgram/mg dry weight) of the scar tissue in the superoxide dismutase and control groups, respectively, were 35.3 +/- 3.8 and 28.7 +/- 5.0 (p less than 0.05). The ratios of the scar thickness to normal wall thickness were superoxide dismutase 0.91 +/- 0.03 and control 0.89 +/- 0.03 (p greater than 0.05). Thus, superoxide dismutase had no adverse effect on wall thickening or scar formation assessed 6 weeks after myocardial infarction, and may be useful to limit oxygen radical-mediated damage during reperfusion of the ischemic myocardium. 相似文献
102.
The regulation of erythropoiesis is primarily controlled by erythropoietin (Ep). Recently, however, other factors that both stimulate and inhibit erythropoiesis have been reported. Using an in vitro liquid culture of bone marrow cells, a factor in normal mouse serum was demonstrated that markedly stimulated heme synthesis by marrow erythroid cells. In this study, the role of this heme synthesis stimulating factor (HSF) and Ep in the erythropoietic suppression caused by endotoxin administration to mice was examined. Although HSF levels did not alter appreciably after endotoxin injection, marrow erythroid cells from these animals became unresponsive to the factor. This could be reversed if Ep was added to the culture in vitro or if the hormone was injected into the mice 18 hr prior to harvesting the marrow. This marrow erythroid cell response is identical to that seen in animals in whom Ep levels are markedly reduced, such as that found in exhypoxic polycythemia, and suggest a decrease in the hormone following endotoxin administration. Additional studies demonstrated that when Ep was injected into mice 6 hr after endotoxin administration, an increase in femoral erythroid colony-forming units (CFU-E), proerythroblast number, and 59 Fe incorporation into femoral marrow cells could be demonstrated. These findings, together with the marrow erythroid cell response to the hormone, suggest that the mechanism for suppression of erythropoiesis after endotoxin injection is a reduction in the level of circulating Ep. 相似文献
103.
Hardcastle Cheshire Hausman Hanna K. Kraft Jessica N. Albizu Alejandro O’Shea Andrew Boutzoukas Emanuel M. Evangelista Nicole D. Langer Kailey Van Etten Emily J. Bharadwaj Pradyumna K. Song Hyun Smith Samantha G. Porges Eric DeKosky Steven T. Hishaw Georg A. Wu Samuel S. Marsiske Michael Cohen Ronald Alexander Gene E. Woods Adam J. 《Age (Dordrecht, Netherlands)》2022,44(2):1011-1027
GeroScience - Prior randomized control trials have shown that cognitive training interventions resulted in improved proximal task performance, improved functioning of activities of daily living,... 相似文献
104.
Julio Fernandez‐Mendoza Sarah Shea Alexandros N. Vgontzas Susan L. Calhoun Duanping Liao Edward O. Bixler 《Journal of sleep research》2015,24(4):390-398
Longitudinal studies that have examined the association of insomnia with incident depression using objective sleep measures are very limited. The aim of this study was to examine the predictive role of the severity of insomnia for incident depression in a general population sample using psychometric and polysomnographic data. From a random, general population sample of 1741 individuals of the Penn State Adult Cohort, 1137 adults without depression were followed up with a structured telephone interview after 7.5 years. All subjects completed a full medical evaluation, 1‐night polysomnogram and Multiphasic Minnesota Personality Inventory at baseline. The incidence of depression was 15%. Poor sleep (odds ratio = 1.5, P = 0.001) and insomnia (odds ratio = 1.9, P = 0.031) were significantly associated with incident depression. The odds of incident depression were highest (odds ratio = 2.2, P = 0.019) in insomnia with objective short sleep duration and independent of Multiphasic Minnesota Personality Inventory Ego Strength scores, an index of poor coping resources. The persistence of insomnia and worsening of poor sleep into insomnia significantly increased the odds of incident depression (odds ratios ranged from 1.8 to 6.3), whereas their full remission did not (odds ratio ranged from 1.2 to 1.8). Insomnia with short sleep duration is associated with incident depression independent of poor coping resources, whereas the association of insomnia with normal sleep duration with incident depression was mediated by poor coping resources. Persistence and worsening of poor sleep or insomnia, but not their full remission, are significant predictors of incident depression. These data suggest that there is a significant relationship between the severity of insomnia and incident depression. 相似文献
105.
Impact of an Evidence-Based Medicine Curriculum on Resident Use of Electronic Resources: A Randomized Controlled Study
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Kim S Willett LR Murphy DJ O'Rourke K Sharma R Shea JA 《Journal of general internal medicine》2008,23(11):1804-1808
Background Evidence-based medicine (EBM) is widely taught in residency, but evidence for effectiveness of EBM teaching on changing residents’
behavior is limited.
Objective To investigate the impact of an EBM curriculum on residents’ use of evidence-based resources in a simulated clinical experience.
Design/Participants Fifty medicine residents randomized to an EBM teaching or control group.
Measurements A validated test of EBM knowledge (Fresno test) was administered before and after intervention. Post intervention, residents
twice completed a Web-based, multiple-choice instrument (15 items) comprised of clinical vignettes, first without then with
access to electronic resources. Use of electronic resources was tracked using ProxyPlus software. Within group pre–post differences
and between group post-test differences were examined.
Results There was more improvement in EBM knowledge (100-point scale) for the intervention group compared to the control group (mean
score increase 22 vs. 12, p = 0.012). In the simulated clinical experience, the most commonly accessed resources were Ovid (71% of residents accessed)
and InfoPOEMs (62%) for the EBM group and UptoDate (67%) and MDConsult (58%) for the control group. Residents in the EBM group
were more likely to use evidence-based resources than the control group. Performance on clinical vignettes was similar between
the groups both at baseline (p = 0.19) and with access to information resources (p = 0.89).
Conclusions EBM teaching improved EBM knowledge and increased use of evidence-based resources by residents, but did not improve performance
on Web-based clinical vignettes. Future studies will need to examine impact of EBM teaching on clinical outcomes. 相似文献
106.
ProMACE/CytaBOM方案治疗难治性或复发性非霍奇金淋巴瘤的疗效观察 总被引:5,自引:0,他引:5
目的:探讨ProMACE/CytaBOM方案治疗难治性和(或)复发性非霍奇金淋巴瘤(NHL)的疗效。方法:采用ProMACE/CytaBOM方案治疗18例难治性和(或)复发性NHL患者,其中难治性NHL患者8例,复发性NHL患者10例。结果:5例难治性和(或)复发性NHL患者达到完全缓解(CR率为27.8%),4例达部分缓解(PR率为22.2%),总有效率为50.0%;目前12例仍生存,其中生存最长者26个月(2例),仍处于CR期。毒副作用主要为消化道症状、轻度肝功能异常以及骨髓抑制。结论:ProMACE/CytaBOM方案对部分难治性和(或)复发性NHL患者仍有效,毒副作用较轻,可用于治疗对其他化疗方案无效的难治性和(或)复发性NHL。 相似文献
107.
108.
Jacques DA Ndawinz Xavier Anglaret Eric Delaporte Sinata Koulla-Shiro Delphine Gabillard Albert Minga Dominique Costagliola Virginie Supervie 《Bulletin of the World Health Organization》2015,93(8):521-528
Objective
To propose two new indicators for monitoring access to antiretroviral treatment (ART) for human immunodeficiency virus (HIV); (i) the time from HIV seroconversion to ART initiation, and (ii) the time from ART eligibility to initiation, referred to as delay in ART initiation. To estimate values of these indicators in Cameroon.Methods
We used linear regression to model the natural decline in CD4+ T-lymphocyte (CD4+ cell) numbers in HIV-infected individuals over time. The model was fitted using data from a cohort of 351 people in Côte d’Ivoire. We used the model to estimate the time from seroconversion to ART initiation and the delay in ART initiation in a representative sample of 4154 HIV-infected people who started ART in Cameroon between 2007 and 2010.Findings
In Cameroon, the median CD4+ cell counts at ART initiation increased from 140 cells/μl (interquartile range, IQR: 66 to 210) in 2007–2009 to 163 cells/μl (IQR: 73 to 260) in 2010. The estimated average time from seroconversion to ART initiation decreased from 10.4 years (95% confidence interval, CI: 10.3 to 10.5) to 9.8 years (95% CI: 9.6 to 10.0). Delay in ART initiation increased from 3.4 years (95% CI: 3.1 to 3.7) to 5.8 years (95% CI: 5.6 to 6.2).Conclusion
The estimated time to initiate ART and the delay in ART initiation indicate that progress in Cameroon is insufficient. These indicators should help monitor whether public health interventions to accelerate ART initiation are successful. 相似文献109.
Charles?E.?BaschEmail author Patricia?Zybert Randi?L.?Wolf Corey?H.?Basch Ralph?Ullman Celia?Shmukler Fionnuala?King Alfred?I.?Neugut Steven?Shea 《Journal of community health》2015,40(5):975-983
This randomized controlled trial assessed different educational approaches for increasing colorectal cancer screening uptake in a sample of primarily non-US born urban minority individuals, over aged 50, with health insurance, and out of compliance with screening guidelines. In one group, participants were mailed printed educational material (n = 180); in a second, participants’ primary care physicians received academic detailing to improve screening referral and follow-up practices (n = 185); in a third, physicians received academic detailing and participants received tailored telephone education (n = 199). Overall, 21.5 % of participants (n = 121) received appropriate screening within one year of randomization. There were no statistically significant pairwise differences between groups in screening rate. Among those 60 years of age or older, however, the detailing plus telephone education group had a higher screening rate than the print group (27.3 vs. 7.7 %, p = .02). Different kinds of interventions will be required to increase colorectal cancer screening among the increasingly small population segment that remains unscreened. ClinicalTrials.gov Identifier: NCT02392143. 相似文献
110.
Effectiveness of immunoglobulin prophylaxis in reducing clinical complications of hematopoietic stem cell transplantation: a systematic review and meta‐analysis
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