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Background. A persistent patent ductus arteriosus (PDA) may delay closure of a coexisting atrial septal defect (ASD) due to volume loading and enlargement of the left atrium. The purpose of this study was to investigate the natural history of ASD size in patients with a PDA following transcatheter PDA occlusion. Methods. All patients with an ASD and a PDA who underwent transcatheter PDA occlusion at Texas Children’s Hospital were identified. Patients with ASD diameter <3 mm, or additional cardiac defects were excluded. Eight patients (7 females) with small‐ to moderate‐sized ASDs and a PDA were identified. Patient demographics, echocardiographic data, and cardiac catheterization data were recorded. Data were analyzed by 1‐tailed t‐test. Results. Following PDA occlusion, ASD diameter decreased in 6 of 8 patients by a mean of 3.8 mm (±2.3 mm), including 2 that closed. The median duration of follow‐up was 689 days. One ASD remained unchanged and 1 increased in size. The mean maximum ASD diameter decreased from 6.4 mm (±2.2 mm) to 3.9 mm (±3.4 mm) (P = .03). Two patients underwent subsequent transcatheter ASD occlusion. Conclusion. Following transcatheter PDA occlusion, small‐ to moderate‐sized ASDs have significant probability to decrease in size, and possibly close. In infants and children, we recommend transcatheter PDA occlusion, and serial follow‐up of the size of the ASD. This will allow many small‐ to moderate‐sized ASDs to either close, or become smaller, obviating the need for future intervention.  相似文献   
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CONTEXT: Although the nonmedical use of stimulant drugs such as cocaine and methamphetamine is increasingly common in many rural areas of the United States, little is known about the health beliefs of people who use these drugs. PURPOSE: This research describes illicit stimulant drug users' views on health and health-related concepts that may affect their utilization of health care services. METHODS: A respondent-driven sampling plan was used to recruit 249 not-in-treatment, nonmedical stimulant drug users who were residing in 3 rural counties in west central Ohio. A structured questionnaire administered by trained interviewers was used to collect information on a range of topics, including current drug use, self-reported health status, perceived need for substance abuse treatment, and beliefs about health and health services. FINDINGS: Participants reported using a wide variety of drugs nonmedically, some by injection. Alcohol and marijuana were the most commonly used drugs in the 30 days prior to the interview. Powder cocaine was used by 72.3% of the sample, crack by 68.3%, and methamphetamine by 29.7%. Fair or poor health status was reported by 41.3% of the participants. Only 20.9% of the sample felt they needed drug abuse treatment. Less than one third of the sample reported that they would feel comfortable talking to a physician about their drug use, and 65.1% said they preferred taking care of their problems without getting professional help. CONCLUSIONS: Stimulant drug users in rural Ohio are involved with a range of substances and hold health beliefs that may impede health services utilization.  相似文献   
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We have previously reported the time trends, design and interventions in randomised controlled trials (RCTs) in cystic fibrosis (CF) from 1961 through 1997 [Cheng K, Smyth RL, Motley J, O'Hea U, Ashby D, Randomised controlled trials in cystic fibrosis (1966-1997) categorized by time, design, and intervention. Pediatr Pulmonol 2000, 29:1-7.]. We maintain an ongoing register of all RCTs and controlled clinical trials (CCTs) in CF and have noted that in the five years since 1997 there has been a 48% increase in published trials. We aimed to assess whether this increase has been associated with an improvement in design quality. All RCTs and CCTs from 1961-2002 were assessed. Two epochs were then compared, 1961-1997 and 1998-2002. For each trial we recorded the design, participant numbers and the intervention studied. 261 trials in 1998-2002 were compared with 544 trials in 1961-1997. Comparing the two epochs a similar proportion of trials were parallel, double-blind and placebo controlled; also the median number of participants was similar. In the later epoch 25% of trials were multicentre, compared with 11% previously. Whilst this recent increase in clinical trials in CF is welcome, this has not been associated with improvements in quality. The trend for an increasing proportion of trials to be multicentre is encouraging. There are however, still deficiencies in the design of clinical trials in CF.  相似文献   
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Surfactant     
Surfactant, a complex substance containing specific proteins and phospholipids, is essential for gas exchange in the lungs. Research shows that surfactant not only lowers surface tension, but also plays a role in host defense. Surfactant replacement therapy is a cornerstone in the treatment of respiratory distress syndrome in premature infants. New information on endogenous surfactant composition including surfactant apoproteins has led to advances in the surfactant replacement products currently available. Because of the success of surfactant deficiency treatment in neonates, surfactant replacement therapy has been studied in both the pediatric and adult population for the treatment of other respiratory disorders. This article describes the composition, metabolism, and function of endogenous surfactant and other uses of surfactant replacement therapies in neonates.  相似文献   
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