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81.

Introduction  

Tissue Doppler imaging (TDI) plays an important role in assessing diastolic function using echocardiography. However, two different methods [pulsed wave (PW-TDI) and color-coded (CC-TDI)] are currently used. We aimed to compare both measurements.  相似文献   
82.
This study aimed to evaluate a laser fluorescence device (the DIAGNOdent) and a visual classification system (ICDAS-II) for occlusal caries diagnosis. It also aimed to determine whether fluorescence measurements taken at the tooth surface correlate with the fluorescence measurements taken within the body of the lesion. The occlusal surfaces of 100 extracted permanent teeth were examined using ICDAS-II and DIAGNOdent (LF-tooth). Serial sections were made and lesion depth was assessed histologically. DIAGNOdent readings were also taken from the sections (LF-section). There were significant positive strong correlations between ICDAS-II and histology (rS = 0.71) and LF-section and histology (rS = 0.70), and only moderate correlations between LF-tooth and histology (rS = 0.51) and LF-tooth and LF-section (rS = 0.60). Diagnostic accuracy for ICDAS-II was generally better than for LF-tooth. While the DIAGNOdent device provides an objective reading for detection and monitoring of carious lesions, using the cut-off ranges previously suggested leads to inferior performance.  相似文献   
83.
Dietary intake during diarrhea in children less than three years of age was estimated from information recorded on illustrated dietary forms used by children's caretakers during the first week of illness in a prospective community-based study of diarrheal diseases in Lima, Peru. The frequency of consumption and the amount consumed of food groups and selected commonly consumed foods were analyzed by the final duration of the diarrheal episode. Cereals were less frequently consumed during the acute phase of diarrheal episodes that ultimately became persistent (>14 days'duration), apparently shortening the duration of the episode by one day (median duration of four days in children not consuming vs three days in children consuming cereals during diarrhea, p <0.02 Kaplan-Meier logrank test). Only roots and tubers (mainly potatoes) were consumed in greater quantity during episodes that became persistent. There was no evidence that consumption of breast milk or non-maternal milk was associated with an alteration in diarrheal duration. This study provides further evidence of the beneficial effects of continuing feeding during diarrhea using foods available at the home level, especially cereals, which are commonly used in the diet of young children.  相似文献   
84.
To study the possible influence of sleeping position on arterial oxygen saturation, measured by pulse oximetry (Sp62), 7–h overnight recordings of breathing movements and ECG were performed in 43 infants (median age 2.4 months, range 0.2–11 months) at increased risk of sudden infant death syndrome (SIDS). Infants were randomly allocated to start sleeping either in their usual sleeping position or in the opposite position. After 3.5 h, all infants were gently turned over. Thus, each infant served as their own control. Recordings were analysed for sleep time, baseline Sp02 (only during regular breathing), and the number and duration of desaturations (a decrease in Sp02 to ≤80%). In the prone position, a significantly higher proportion of time was spent asleep (median 79% versus 70%; p < 0.05). Median baseline Sp02 was 98.8% (91.7–100%) in the prone and 99.0% (92.0–100%) in the supine position (ns). A total of 191 desaturations were found in 29 recordings; 96 in the prone and 95 in the supine position (ns). One infant subsequently died of SIDS while sleeping in the prone position. He had a relatively high number of desaturations (n = 12) which all occurred in the prone position. These results confirm earlier studies which could not find a significant influence of sleeping position on baseline oxygenation. The occurrence of desaturations in the prone position only in the infant who subsequently died requires further investigation.  相似文献   
85.
86.
OBJECTIVES: The purpose of this study was to evaluate predictors of change in household size and institutionalization in late life. METHODS: The Duke Established Populations for Epidemiologic Studies of the Elderly cohort (n = 3730) was assessed annually (1986-1996). Independent variables included home ownership, income, cognitive and functional ability, chronic illness, mood, household size, social support, and stressful life events. Competing risk of household expansion or institutionalization was modeled using (a) hazard of either event and (b) odds of household expansion or institutionalization among elders who experienced an event. RESULTS: Hazard of either event was associated with younger age, Black race, lower income, cognitive problems and stability, functional abilities and deterioration, low chronic illness burden, being unmarried, having more living children, and recent life events. Among those who reported either event, odds of institutionalization (vs. household expansion) were associated with older age, White race, cognitive and functional problems, high chronic illness burden, being married, having fewer living children, smaller household size, social isolation, and exits of nonspouse coresidents. DISCUSSION: Modeling separate effects of whether there was a household expansion or institutionalization, and if so, which type of event occurred, and taking into account acute and evolving states, enabled more precise understanding of the complex mechanisms involved in determining continued community residence or institutionalization.  相似文献   
87.
Pediatric trauma performance improvement programs may share some of the criteria tracked by their counterparts in the adult trauma world. However, some of the criteria must be specific to the unique diagnostic and therapeutic needs of children. Nine criteria are defined in terms of the critical issues, what information is required to evaluate the appropriateness of the care provided in regards to those issues, and acceptable thresholds for review. In addition, practical aspects of multi-disciplinary peer review in the performance improvement process is presented.  相似文献   
88.
The Internet (electronic mail and the World Wide Web) may provide new opportunities for communication that can help older adults avoid social isolation. This randomized controlled trial assessed the psychosocial impact of providing Internet access to older adults over a five-month period. One hundred volunteers from four congregate housing sites and two nursing facilities were randomly assigned to receive Internet training or to a wait list control group. The pre & post measures included the UCLA Loneliness scale, modified CES Depression scale, a measure of locus of control, computer attitudes, number of confidants, and overall quality of life. Participants received nine hours of small group training in six sessions over two weeks. Computers were available for continued use over five months and the trainer was available two hours/week for questions. At the end of the trial, 60% of the intervention group continued to use the Internet on a weekly basis. Although there was a trend toward decreased loneliness and depression in intervention subjects compared to controls, there were no statistically significant changes from baseline to the end of trial between groups. Among Internet users (n = 29) in the intervention group there were trends toward less loneliness, less depression, more positive attitudes toward computers, and more confidants than among intervention recipients who were not regular users (n = 19) of this technology. Most elderly participants in this trial learned to use the Internet and the majority continued to use it on a weekly basis. The psychosocial impact of Internet use in this sample suggested trends in a positive direction. Further research is needed to determine more precisely, which older adults, residing in which environmental contexts are more likely than others to benefit from this rapidly expanding information and communication link.  相似文献   
89.
The purpose of this study was to assess the effect of epilepsy surgery on seizure outcome in children and adolescents under 18 years with intractable epilepsy due to focal cortical dysplasia. We analysed clinical data, such as age at seizure onset, epilepsy course, localisation of focus from presurgical evaluation, MRI, tissue pathology and seizure outcome in 68 patients 6 months to 9 years after epilepsy surgery. Seizure outcome was classified according to the Engel classification. Mean age at seizure onset was 7 months, ranging from the first days of life to 7 years. All patients had medically intractable epilepsy. Localisation of the lesion was predominantly extratemporal: posterior (uni- or multilobar) 43 %, frontal without central region 26 %, multilobar involving central area 19 % and temporal in 12 %. MRI signs typically seen in cortical dysplasia (FCD) such as localised blurring of gray-white matter junction was found in 68 %, dysgyria in 62 %, thickening of the cortical ribbon in 46 % and T2 signal elongation of the subcortical white matter in 40 % of the patients' MRI. Age at surgery ranged from 5 months to 16 years; 14 patients were under 2 years when operated on. In 34 patients (6 patients under 3 years) subdural grid electrode evaluation was performed prior to surgery. Pathology revealed focal cortical dysplasia without balloon cells (type I) in 60 %, FCD of the balloon cell subtype (type II) in 40 % of the specimens. Postoperative complications were subdural hygroma in 5 and an increased motor deficit in 2 patients. Up to two years after epilepsy surgery 50 % of the children were seizure free (Engel class I), 10 % Engel class II, 33 % Engel class III and 7 % unchanged (Engel class IV). Long-term seizure outcome (> 3 years post surgery) in 32 patients showed similar results (class I 50 %, class II 19 %, class III 28 %, class IV 3 %). Complete resection of the dysplastic lesion was significantly correlated with favorable seizure outcome, whereas seizure outcome was not significantly different in patients with mild (type I) or balloon cell (type II) FCD. Children operated after 6 years of age had no better outcome than children operated in infancy or at preschool age. Epilepsy surgery resulted in good (class I and II) seizure control in 60 % of children with intractable epilepsy due to focal cortical dysplasia.  相似文献   
90.
BACKGROUND: Ventricular septal defect (VSD) complicating acute myocardial infarction has been studied primarily in small, prethrombolytic-era trials. Our goal was to determine clinical predictors and angiographic and clinical outcomes of this complication in the thrombolytic era. METHODS AND RESULTS: We compared enrollment characteristics, angiographic patterns, and outcomes (30-day and 1-year mortality) of patients enrolled in the Global Utilization of Streptokinase and TPA for Occluded Coronary Arteries (GUSTO-I) trial with and without a confirmed diagnosis of VSD. Univariable and multivariable analyses were used to assess relations between enrollment factors and the development of VSD. In all, 84 of the 41 021 patients (0.2%) developed VSD, a smaller percentage than reported in the prethrombolytic era. The median time from symptom onset to VSD diagnosis was 1 day. Enrollment factors most associated with this complication were advanced age, anterior infarction, female sex, and no previous smoking. The infarct artery was more often the left anterior descending and more likely to be totally occluded in patients who developed VSD. Mortality at 30 days was higher in patients with VSDs than in those without this complication (73.8% versus 6.8%, P<0.001). Patients with VSDs selected for surgical repair (n=34) had better outcomes than patients treated medically (n=35; 30-day mortality, 47% versus 94%). CONCLUSIONS: Compared with historical control subjects, patients who undergo thrombolysis within 6 hours of infarction onset may have a reduced risk of later VSD. If patients develop this mechanical complication, however, it typically occurs sooner than described in the prethrombolytic era. Despite improvements in medical therapy and percutaneous and surgical techniques, mortality with this complication remains extremely high.  相似文献   
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