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Background  

Atrial fibrillation (AF) is the most common sustained dysrhythmia and appears to be an independent predictor of sudden cardiac death. The irregular ventricular rhythm contains both linear and non-linear patterns; however, it remains unclear whether vagally mediated effects are present within these patterns.  相似文献   
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Objectives/background: Pregnant women report disturbed sleep beginning in early pregnancy. Among nonpregnant populations, exercise has been associated with improved sleep; however, research in pregnant samples has been equivocal. We examined whether varying degrees of exercise were associated with better nocturnal sleep among pregnant women during early gestation. Participants: 172 pregnant women. Methods: Self-reported sleep and exercise and objective sleep were collected during early gestation: T1 (10–12 weeks), T2 (14–16 weeks), and T3 (18–20 weeks) from 172 pregnant women. Exercise was categorized into three time-varying groups: 0 metabolic equivalent minutes per week (MET-min/week), 1 to < 500 MET-min/week, or ≥ 500 MET-min/week. Linear mixed-effects models were employed to test hypotheses. Results: A significant main effect for Time (F[2,254] = 9.77, p < 0.0001) and Time*Exercise group interaction were observed for actigraphic sleep efficiency (aSE) (F[4,569] = 2.73, p = 0.0285). At T2, women who reported ≥ 500 MET-min/week had higher aSE than those who reported 0 MET-min/week. Significant main effects for Exercise Group and Time were observed for actigraphic wake after sleep onset (aWASO; F[2,694] = 3.04, p = 0.0483 and F[2,260] = 3.21, p = 0.0419). aWASO was lowest for those reporting 1 to < 500 MET-min/week (t[701] = 2.35, adjusted p = .0489) and aWASO decreased from T1 to T3 (t[258] = 2.53, adjusted p value = 0.036). Lastly, there was a main effect for Time for the PSQI (F[2,689] = 52.11, p < 0.0001), indicating that sleep quality improved over time. Conclusions: Some level of exercise among pregnant women appears to be more advantageous than no exercise at all. Moderate exercise, while still unclearly defined, may be a worthwhile adjunct treatment to combat sleep disturbances during pregnancy.  相似文献   
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High-dose intravenous gammaglobulin (IVIgG) was given to 12 children and adults with chronic idiopathic thrombocytopenic purpura (ITP) to avoid splenectomy or because they either failed to respond to or required maintenance with high doses of steroids and/or immunosuppressives. The average platelet count increase to initial therapy was 239,500/microliters (range 23,000-790,000). A concomitant IgG Fc receptor blockade, measured by IgG-sensitized 51Cr-labeled autologous erythrocytes, was seen in 11 of 11 patients tested, both splenectomized and not splenectomized, lasting 3-4 wk. Six or more months after treatment, 2 children are in remission, 2 children and 2 adults are stable requiring no therapy with platelet counts of approximately 50,000 and 30,000, respectively, 3 children require maintenance IVIgG therapy at 2-10-wk intervals, and 1 child and 2 adults have become refractory to further IVIgG. Splenectomy was not performed in 4 children. Two adults were able to discontinue daily prednisone. The 3 patients who became unresponsive to Swiss Red Cross gamma-globulin (IgSRK) therapy did so in conjunction with a markedly elevated platelet-associated IgG and IgM. Serum IgM increased an average of 103 mg/dl after the IVIgG infusions. No significant side effects were seen.  相似文献   
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