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Objectives. We studied the duration and prognostic significance of atrial arrhythmias in the denervated transplanted heart, specifically the occurrence of atrial fibrillation in the absence of vagal modulation.

Background. Substantial animal data indicate that vagally induced dispersion of atrial refractoriness plays a central role in the induction and maintenance of atrial fibrillation.

Methods. We studied the occurrence of atrial arrhythmias in the denervated hearts of 88 consecutive orthotopic transplantations in 85 patients by means of continuous telemetry and all available electrocardiographic tracings.

Results. Fifty percent of recipients (44 of 88) developed at least one atrial arrhythmia. Atrial fibrillation occurred 23 times (21 recipients), atrial flutter 39 times (26 recipients), ectopic atrial tachycardia 3 times (3 recipients) and supraventricular tachycardia 18 times (11 recipients). The number of atrial fibrillation and atrial flutter episodes did not differ (23 vs. 39, p = 0.072), but the fibrillation (37.0 ± 10 vs. 6.6 ± 3.6 h, p = 0.014). Atrial fibrillation was associated with an increased risk of subsequent death (10 of 21 recipients with vs. 15 of 67 without atrial fibrillation, risk ratio 3.15 ± 0.18, p = 0.005 by Cox proportional hazards model). All 5 recipients who developed “late” atrial fibrillation (>2 weeks after transplantation) died versus 5 of 16 who developed atrial fibrillation within the first 2 weeks (p = 0.007). Causes of death included rejection (three recipients), allograft failure (two recipients), infection (three recipients) and multiorgan failure (two recipients). Atrial fibrillation was not associated with age, gender, ischemic time, reason for transplantation, echocardiographic variables, invasive hemodynamic variables or biopsy grade. Mean time from atrial arrhythmia to echocardiography was 2.7 ± 3.3 days; that to biopsy was 4.8 ± 6.3 days. Atrial flutter was not associated with subsequent death. Only 7 (15.9%) of 44 recipients demonstrated moderate or severe allograft rejection at the time of the arrhythmia.

Conclusions. Atrial arrhythmias occur frequently in the denervated transplanted heart, often in the absence of significant rejection. Late atrial fibrillation may be associated with an increased all-cause mortality.  相似文献   

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In this study, the light-emission properties of carious and sound root surfaces were investigated under a wide range of excitation wavelengths. Human molar teeth with exposed root surfaces containing light- and dark-discolored root caries (n = 3 of each) were selected. Emission spectra were recorded from carious and corresponding sound root surface areas from each tooth by using a fluorescence spectrophotometer at excitation wavelengths from 360 nm up to 580 nm, in steps of 20 nm. The spectra were corrected for fluctuations in detector sensitivity and excitation light intensity, and normalized to peak intensity. Excitation spectra were recorded for selected emission wavelengths that showed maximum intensity. Light- and dark-discolored root surface caries showed distinct fluorescence emission bands between 600 and 700 nm that were not present in sound root surface areas. These bands were strongest for excitation wavelengths between 390 and 420 nm. The excitation spectra of root caries revealed maximum excitation at around 405 nm, which is equivalent to the Soret band of porphyrin compounds. The emission spectra of both types of root caries lesions were shifted towards longer wavelengths (red shift at half maximum) when compared to the spectra of corresponding sound root surfaces. The red shift for dark-discolored root caries was higher than for light-discolored lesions at all excitation wavelengths.  相似文献   
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AIM: To determine the frequency of use of dental anxiety assessment questionnaires and factors associated with their use in a group of UK dental practitioners. METHOD: A postal questionnaire to all 328 dentists whose names appear in the British Society for Behavioural Sciences in Dentistry Directory. Information collected for each practitioner included gender, year of qualification, type of practice in which anxious dental patients were treated, treatment used to manage anxious dental patients, type and frequency of use of dental anxiety assessment indices. RESULTS: Questionnaires were returned from 275 (84%) practitioners. 269 were analyzed. Only 54 practitioners (20%) used adult dental anxiety assessment questionnaires and only 46 (17%) used child dental anxiety assessment questionnaires. Male practitioners were more likely to report questionnaire use in comparison with females (P< 0.05), when treating dentally anxious adults (26% v 14%). In addition, practitioners providing intravenous sedation were more likely to use an adult dental anxiety questionnaire (P < 0.04) than those who did not use intravenous sedation (29% v 15%). The type of treatment provided had a significant association with the use of child dental anxiety. Those providing general anaesthesia (P = 0.03) and hypnosis (P = 0.01) for dentally anxious children were more inclined to use a questionnaire. CONCLUSION: The use of pre-treatment dental anxiety assessment questionnaires was low in this group of dentists. Male practitioners and those providing intravenous sedation, general anaesthesia or hypnosis seem more likely to use dental anxiety assessment questionnaires.  相似文献   
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This paper considers the impact of pubertal status and pubertal timing on disordered eating in Irish adolescents. 1190 boys and 1841 girls completed the Eating Attitudes Test‐26, the Eating Disorder Inventory‐III and self‐report measures of pubertal status and pubertal timing. Regarding pubertal status, greater maturity in girls was associated with increased overall eating concerns, higher drive for thinness and higher levels of body dissatisfaction. In boys, greater maturity was associated with lower drive for thinness and lower body dissatisfaction. Regarding pubertal timing, early‐maturing girls showed the most eating concerns, the highest drive for thinness, scored highest on bulimic symptoms and were the most dissatisfied with their bodies. In contrast, late‐maturing boys had more bulimic symptoms and more dissatisfaction with their bodies than on‐time peers. The findings suggest that puberty itself is a risk factor for disordered eating for girls rather than boys; however, pubertal timing is a risk factor for both. Copyright © 2012 John Wiley & Sons, Ltd and Eating Disorders Association.  相似文献   
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BACKGROUND: Low procedural complication rates, barriers to access, and patient preference have encouraged the development of percutaneous coronary intervention (PCI) programs at centers that are often closer to home but without on-site cardiac surgical capability. OBJECTIVES: We compared clinical and economic outcomes associated with performing low-risk elective PCI at a community hospital without on-site cardiac surgery with those obtained at a more remote tertiary care center with on-site cardiac surgery. DESIGN AND MEASURES: We matched 257 patients undergoing low-risk, elective PCI at a community hospital (Immanuel St. Joseph's Hospital [ISJ] between January 27, 2000, and July 31, 2002) to 514 PCI patients treated at a tertiary care hospital (Saint Marys Hospital [SMH] between January 27, 2000, and April 30, 2002) based on clinical and lesion criteria. Clinical outcomes (in-hospital procedural success and target vessel failure during long-term follow up) and economic outcomes (direct medical costs, billed charges, and hospital length of stay [LOS]) were compared between groups. The Mayo Clinic PCI Registry (containing clinical, angiographic, and follow-up data) and administrative data were used in matching and outcomes assessment. RESULTS: Procedural success was achieved more often among ISJ-treated patients (99% vs. 95%; P = 0.02); however, no difference in target vessel failure rates was observed during a median follow-up time of 3.1 years (estimated 1-year event rate: 15.2% vs. 14.8%; P = 0.46). ISJ-treated patients incurred, on average, $3024 more in estimated total costs ($13,771 vs. $10,746; P < 0.001) and $6084 more in billed charges (P < 0.001), but incurred similar LOS post procedure (1.53 days). CONCLUSIONS: Similar clinical outcomes were achieved at a community hospital without on-site cardiac surgery but at significantly increased direct medical cost. Patients, providers, hospitals, payers, and policymakers should consider whether the benefits associated with locally provided specialized cardiovascular services warrant this additional cost.  相似文献   
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