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21.
Summary Right and left ventricular (RV, LV) function were evaluated by quantitative bi-plane cineangiocardiography in 20 patients, aged 1 day to 6 years, who had primary myocardial disease presenting with heart failure. RV end-diastolic volume (RVEDV) was 157%±63% ( ±SD) of normal (P<.01), and RV ejection fraction (EF) was 0.39±0.16 (normal, 0.65±0.08) (P<.01). Left Ventricular end-diastolic volume (LVEDV) was 331%±172% of normal and LVEF 0.26±0.12 (normal, 0.68±0.05); both values were different from normal (P<.01) and also different from corresponding RV values (P<.01). RVEDV was larger than LVEDV in only four patients, these four patients being the youngest patients in the entire group, all 10 days of age or younger. A subgroup of 14 patients with subnormal RVEF (RVEF> –2 SDs of normal) were compared with six patients with normal RVEF. Patients with subnormal RVEF had larger left ventricles, lower LVEFs, and higher RV peak systolic pressure than those with normal RVEF (P<.05 for all three comparisons). A separate subgroup of ten patients who died was compared with a subgroup of eight surviving patients followed up for one to four years after diagnosis. Patients who died had lower values for LVEF and LV systolic output and higher values for LV end-diastolic pressure than did survivors. There were no significant differences between patients who died and survivors in any of the RV variables measured. RV functional abnormalities were generally present in both infants and children who had myocardial disease presenting with heart failure and may especially contribute to the symptoms in infants.Supported in part by grant HL 21985-01 from the National Heart, Lung, and Blood Institute  相似文献   
22.
Abstract

Issue: Although there is consensus on the importance of including ethics in the medical school curriculum, there is wide variation in how this topic is taught. Recent literature also questions the effectiveness of current ethical teaching methods in changing student attitudes and future behavior. Furthermore, from the student perspective, there is a marked disconnect between the stated importance of and lack of effort in ethics courses. Evidence: Applying a student perspective of the hidden curriculum, as well as reviewing and applying insight from the available literature, we advocate for alignment of instructional design, content, and assessments. This article provides specific recommendations to increase student engagement in ethics courses and concludes by discussing whether a lack of engagement is attributable to intrinsic qualities of medical students in addition to pedagogical technique and educational setting and culture. Implications: This article has practical suggestions for medical educators to improve their ethics courses, leading to more well-rounded and thoughtful physicians.  相似文献   
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24.
Sleep problems (long wake episodes, low sleep efficiency) were examined as moderators of the relation between children's intelligence and academic achievement. The sample was comprised of 280 children (55% boys; 63% European Americans, 37% African Americans; mean age = 10.40 years, SD = 0.65). Sleep was assessed during seven consecutive nights of actigraphy. Children's performance on standardized tests of intelligence (Brief Intellectual Ability index of the Woodcock–Johnson III) and academic achievement (Alabama Reading and Math Test) were obtained. Age, sex, ethnicity, income‐to‐needs ratio, single parent status, standardized body mass index, chronic illness and pubertal development were controlled in analyses. Higher intelligence was strongly associated with higher academic achievement across a wide range of sleep quality. However, the association between intelligence and academic achievement was slightly attenuated among children with more long wake episodes or lower sleep efficiency compared with children with higher‐quality sleep.  相似文献   
25.
The present study investigated whether salient preadolescent behaviors and experiences predicted parents’ and teachers’ underestimation of preadolescents’ shyness. Participants included a community sample of 129 fifth and sixth graders, along with one parent and teacher per preadolescent. Preadolescents, parents, and teachers provided reports about preadolescents’ shyness, and parents and teachers rated preadolescents’ prosocial and aggressive behaviors, peer victimization experiences, and academic performance. Results indicated that parent- and teacher-reported prosocial behavior, teacher-reported aggressive behavior, and parent-reported peer victimization were associated with lower parent and teacher reports of preadolescent shyness, relative to preadolescent reports, controlling for demographic variables and parent stress. Additionally, higher parent-reported academic performance was associated with lower teacher reports of preadolescent shyness, compared to preadolescent reports. These findings suggest that preadolescents with higher levels of relatively conspicuous behaviors and experiences feel more shyness than their parents and teachers report.  相似文献   
26.
Background:  Previous theory and research suggest links between substance use and externalizing behavior problems, but links between substance use and internalizing problems are less clear. The present study sought to understand concurrent links among diagnoses of substance use disorders, internalizing disorders, and behavior disorders at age 18 as well as developmental trajectories of illicit substance use prior to and after this point.
Methods:  Using data from 585 participants in the Child Development Project, this study examined comorbidity among substance use, behavior, and internalizing disorders at age 18 and trajectories of growth in illicit substance use from age 12 to age 22.
Results:  In this community sample, meeting diagnostic criteria for comorbid internalizing disorders, a behavioral disorder (conduct disorder or oppositional defiant disorder) alone, or both internalizing and behavioral disorders predicted higher concurrent substance use disorders (abuse, dependence, or withdrawal). Meeting diagnostic criteria for an anxiety disorder alone or depression alone did not predict higher concurrent substance use diagnoses. Over time, youths with behavioral disorders at age 18 showed a pattern of increasing substance use across early adolescence and higher levels of substance use than those with no diagnosis at age 18. Substance use declines from late adolescence to early adulthood were observed for all groups.
Conclusions:  Substance use disorders were more highly comorbid with behavior disorders than with internalizing disorders at age 18, and behavior disorder and comorbid behavior-internalizing disorders at age 18 were related to trajectories characterized by steep increases in illicit substance use during adolescence and high rates of illicit substance use over time.  相似文献   
27.
To study the temporal relationship of occlusion and reperfusion we examined 16 patients (14 m, 2f) with variant angina for the occurrence and time course of arrhythmias with episodes of ST-elevation (n = 82). The patients underwent frequency-modulated ambulatory ECG recording, episodes of ST elevation were defined, and the arrhythmias were counted before, during and after each episode. In 10 patients (group A) no or only infrequent extrasystoles occurred. Of the other 6 patients (group B), one had a-v block II degree, 5 had frequent (greater than 2/min) ventricular or supraventricular premature beats, 3 with couplets or runs of VPB. Patients of group A and B did not differ in age, severity of fixed coronary stenoses and ventricular ejection fraction. There was a tendency towards a greater incidence of higher ST-elevations (greater than 2 mm) in group B (4 of 6 patients versus 2 of 10 in group A, p = 0.09). The relationship of arrhythmias and ST changes showed different patterns: the maximum of arrhythmias occurred during the episode in 3 patients, during and after the episode in 2 patients and only after the episode in 1 patient. Potentially dangerous arrhythmias are frequent in patients with variant angina and persist beyond the ST segment changes in one half of the affected patients.  相似文献   
28.
The hospital mortality and major factors contributing to hospital morbidity and postoperative length of stay were examined in 597 consecutive patients 70 years of age and older who underwent isolated coronary artery bypass grafting (CABG) between January, 1978, and December, 1983. The mean age of the patients was 73 years, and 66% were men. Unstable angina was present in 59% of patients, left main coronary disease in 13%, and moderate or severe left ventricular dysfunction in 10%. The mean number of arteries grafted per patient was 3.4. The hospital mortality was 2.7% (16 patients) and was higher than the mortality among 4,125 patients less than 70 years of age (0.4% in 18 patients) operated on during the same interval (p less than 0.001). In multivariate regression analyses, age of 80 years or greater, evolving myocardial infarction, serious coexisting illness, major left ventricular dysfunction, emergent operation, and the development of major postoperative complications were significant (p less than 0.05) independent predictors of increased hospital mortality. Major complications occurred in 135 patients (23%). In multivariate analyses, the presence of vascular disease, serious concomitant illness, and the need for urgent or emergent operation were significant independent predictors of the development of major postoperative complications. The mean duration of postoperative hospital stay was 10.6 +/- 6 (standard deviation) days. In multivariate analyses, the development of major postoperative complications was the only variable independently predictive of prolonged hospital stay. With current techniques, CABG procedures can be safely performed in the elderly with mortality and morbidity rates only slightly higher than those in younger patients.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
29.
Restrictive cardiomyopathy in an infant with massive biatrial enlargement and normal ventricular size has been reported only once previously [3]. We now present a 13-month-old patient with severe and progressive congestive heart failure who demonstrated normal ventricular cavity size with biatrial enlargement. Ejection fraction and echocardiographic ventricular function studies were normal.  相似文献   
30.
Children's vagal tone and vagal suppression were examined as moderators of associations between children's sleep disruptions and adjustment problems. A relatively large sample (n = 167) of boys and girls who ranged in age between 8 and 9 years participated with their parents. Sleep was examined via actigraphy in the child's home for seven consecutive days. Children's vagal tone was examined during baseline conditions, and their vagal suppression was assessed in response to an inter-adult argument. In comparison with children exhibiting higher levels of vagal tone, those with lower vagal tone were at increased risk of externalizing problems, depression symptoms and higher body mass index associated with increased sleep disruptions (i.e. lower Sleep Efficiency, increased Wake Minutes and fewer Sleep Minutes). Thus, lower vagal tone functioned as a vulnerability factor for adjustment problems in the context of sleep problems. A higher level of vagal suppression to the inter-adult argument functioned as a protective factor against externalizing behaviors otherwise associated with increased Wake Minutes and reduced Sleep Efficiency. Findings demonstrating the moderating role of vagal functioning in the context of sleep disruptions are novel, and highlight the importance of individual differences in children's physiological regulation for sleep and adjustment.  相似文献   
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