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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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Studies have not previously considered postdisaster adjustment in the context of psychiatric disorders. After the Oklahoma City bombing, a volunteer sample of 181 firefighters who served as rescue and recovery workers was assessed with a structured diagnostic interview. The firefighters had relatively low rates of posttraumatic stress disorder (PTSD) and described little functional impairment, positive social adjustment, and high job satisfaction. PTSD was associated with reduced job satisfaction and functional impairment, providing diagnostic validity. Turning to social supports, seeking mental health treatment, and taking medication were not widely prevalent coping responses. Postdisaster alcohol use disorders and drinking to cope were significantly associated with indicators of poorer functioning. Surveillance for problem drinking after disaster exposure may identify useful directions for intervention.  相似文献   
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Treatment of mouse muscular dystrophy with the protease inhibitor pepstatin   总被引:3,自引:0,他引:3  
Dystrophic mice were treated for 5 weeks beginning at 3 weeks of age with 20 ugm per day of pepstatin, a potent inhibitor of cathepsin D. Mortality was less and weight gain greater in pepstatin treated mice than in controls. Muscle bulk was greater and hind lamb contractures were reduced in treated mice. Mean muscle fiber mass was significantly increased by pepstatin treatment. Inhibition of muscle protease may be the mechanism by which pepstatin slows the tempo of progression of mouse muscular dystrophy.  相似文献   
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Background

Tamoxifen, used as adjuvant therapy for carcinoma breast in postmenopausal women to prevent relapse has estrogenic effect on the endometrium.

Methods

104 patients on tamoxifen for more than six months were subjected to a clinical examination and transvaginal sonography. Patients with endometrial thickness > 8 mm were further evaluated by hysteroscopy and endometrial biopsy.

Results

35(34%) patients were symptomatic. The average endometrial thickness was 11.2 mm which correlated with duration of tamoxifen use. 27(48%) patients had abnormal hysteroscopic findings. 35 (63%) of endometrial biopsies revealed abnormal endometrium. One case of endometrial carcinoma was diagnosed. The results were statistically analysed. There is a significant association between symptomatic status and endometrial thickness and duration of tamoxifen use.

Conclusion

All patients on long term tamoxifen should be annually screened for endometrial pathology.Key Words: Tamoxifen, Endometrium, Transvaginal sonography  相似文献   
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