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Objectives:  The goal of this retrospective study was to examine factors differentiating persons with bipolar disorder who did or did not have comorbid lifetime substance use disorders (SUD) at an index assessment. We also explored the chronology of onset of mood and SUD.
Methods:  We studied 146 subjects with DSM-defined bipolar disorder. Subgroups with and without lifetime SUD were compared on demographic and clinical measures.
Results:  Substance abuse disorders in this bipolar sample were associated with male sex, impulsive-aggressive traits, comorbid conduct and Cluster B personality disorders, number of suicide attempts and earlier age at onset of a first mood episode. In a multivariable logistic regression analysis, male sex and aggression and possibly earlier age at mood disorder onset were associated with SUD. In those with or without SUD, the first mood episode tended to be depressive and to precede the onset of SUD.
Conclusions:  In persons with bipolar disorder, an earlier age of onset and aggressive traits appear to be factors associated with later development of comorbid SUD.  相似文献   
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OBJECTIVE: To investigate the cause of the transient weakness that occurs in recessive myotonia congenita (RMC) following sustained muscle contraction. METHODS: Nerve excitability studies were performed on a 35-year-old male with RMC due to a novel 696+1G>A CLCN1 mutation. The median nerve was stimulated at the wrist and compound muscle action potentials (CMAPs) were recorded from abductor pollicis brevis (APB). Stimulus-response behaviour using two stimulus durations, threshold electrotonus to 100-ms polarizing currents, a current threshold relationship and the recovery of excitability following supramaximal stimulation were recorded at rest. Excitability parameters were also recorded before and after maximal voluntary contraction (MVC) of APB against resistance for 60s. Results were compared to data obtained from 12 normal controls. RESULTS: Baseline axonal excitability parameters were all normal, indicating that axonal function was normal at the point of stimulation. Following one minute of MVC, excitability parameters demonstrated a significant increase in threshold when compared to controls (RMC 54.9%; controls 15.5+/-3.1%). In the RMC patient, this increase in threshold was associated with a 39% reduction in the amplitude of the maximal CMAP, which remained unaffected in controls. CONCLUSIONS: The reduction in maximal CMAP is likely to represent muscle activation failure due to depolarization block, with the increase in threshold possibly reflecting a compensatory attempt by motor axons to overcome prolonged contraction-induced changes in the muscle membrane. SIGNIFICANCE: The prolonged recovery of excitability following sustained muscle contraction is likely to be a contributing factor to symptoms of weakness and fatigue experienced by RMC patients.  相似文献   
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OBJECTIVE: This analysis examined whether patients with Alzheimer disease (AD) tolerate continuous positive airway pressure (CPAP). METHOD: Thirty patients with AD were randomized to CPAP or sham CPAP and completed sleep, depression, and quality-of-life questionnaires. Participants could choose to continue treatment after the trial. RESULTS: Patients wore CPAP for 4.8 hours per night. More depressive symptoms were associated with worse adherence (rS=-0.37; N=30, p<0.04). Patients who continued using CPAP had fewer depressive symptoms (t [19]=2.45, p=0.02) and better adherence (t [19]=2.32, p=0.03) during the trial. CONCLUSION: Patients with AD with obstructive sleep apnea can tolerate CPAP. Adherence and long-term use may be more difficult among those patients with more depressive symptoms.  相似文献   
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Background  

Resident-led morning report is an integral part of most residency programs and is ranked among the most valuable of educational experiences. The objectives of this study were to evaluate the effect of a resident-as-teacher educational intervention on the educational and teaching experience of morning report.  相似文献   
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