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41.
After an abrupt decrease in pacing cycle length (PCL), the ventricular effective refractory period (VERP) shortens. The pacing protocol needed to determine accurate and reproducible values for the VERP during this process is elaborate and time consuming. In this study, steady-state values of VERP at 800 and 350 msec PCL and dynamic values of VERP due to an abrupt change in PCL from 800 to 350 msec were determined. This was done for 11 different dogs to test the interindividual variation and repetitively in the same dog to test the intraindividual variation. The results for steady-state and dynamic values of the VERP show a wide range for both groups. This means that accurate prediction of steady-state and dynamic values of VERP based on previous measurements is not possible.  相似文献   
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STUDY OBJECTIVE: Compared with men, women presenting to the emergency department with acute asthma are more likely to be admitted and to have a longer hospital stay. This study compares peak expiratory flow rate (PEFR) with reported symptom severity between men and women with acute asthma. The null hypothesis was that men and women report similar severity symptoms for similar levels of airway obstruction. METHODS: This study combined data from 4 prospective cohort studies performed from 1996 to 1998 as part of the Multicenter Airway Research Collaboration. Using a standardized protocol, investigators at 64 EDs in 21 US states and 4 Canadian provinces provided 24-hour per day coverage for a median of 2 weeks. RESULTS: Of the 1,291 patients with moderate to severe exacerbations (initial percentage of predicted PEFR <80%), 62% were women. Women were more likely than men to report "severe" complaints in terms of symptom frequency, symptom intensity, and resulting activity limitations (all P <.05). Women with moderate exacerbations were especially likely to describe their exacerbation as causing "severe" activity limitations (sex-PEFR interaction, P =.05). CONCLUSION: Men are less likely than women to report severe asthma symptoms and activity limitations in the presence of airway obstruction. This finding supports use of objective measures of airway obstruction when managing patients with asthma so that those whose symptoms do not reflect the severity of their obstruction can be recognized and properly treated. It also reconfirms the need for increased research on differences between men and women in acute asthma.  相似文献   
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Congenital abnormalities of the coronary sinus (CS) are rare but can be responsible for unsuccessful implantation of a cardiac resynchronization therapy device. We report the case of an ectopic drainage of the CS in the left atrium. A left ventricular lead was implanted by the transseptal route. (PACE 2013; 36:e51–e52)  相似文献   
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A comparison was made to determine the ability of optimal sets of 2–6 unipolar leads and a normal Holter lead set to estimate ST potential distributions changes induced by balloon inflation during angioplasty. The performance of these lead nets was compared to measurements observed in recorded 32-lead body surface maps. Unipolar lead potentials were estimated using a linear, least mean squared error estimator of the total body surface map. The correlation between maximum ST potential change in the body surface map and that predicted by the unipolar lead sets ranged from 0.84–0.93. The correlation between maximum ST segment change measured from the body surface map and measured from the Holter leads was 0.29. Therefore, shifts in ST segment potentials can accurately be estimated from a small number of unipolar leads. In contrast, current bipolar ambulatory recording techniques may introduce significant bias to such estimates.  相似文献   
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The goal of this study was to evaluate the characteristics of primary alcoholics with alcoholic hallucinosis. Six hundred and forty-three primary alcoholic men were recruited from a 28-day Alcohol and Drug Treatment Program at the San Diego VA Medical Center. Subjects only experiencing perceptual abnormalities during alcohol withdrawal, drug-related hallucinosis, as well as those having abnormal sensations that did not meet criteria for hallucinations were excluded from the present study. The remaining 532 subjects were divided into Group 1 {n =48}, which consisted of subjects with a DSM-HIR and ICD-10 diagnosis of alcoholic hallucinosis, and Group 2 (n –484) which consisted of those without any history of hallucinations. A comparison of the two groups revealed that Group 1 men were younger at the onset of alcohol problems, consumed more alcohol per occasion, developed more alcohol-related life problems, and had higher rates of drug experimentation as well as more different types of drugs used. This study suggests that primary alcoholics who consume more drugs and/or alcohol might be at an increased risk for developing alcoholic hallucinosis.  相似文献   
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