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101.
Given that reading, spelling and arithmetic skills are acquired through childhood, their development may be compromised following a childhood traumatic brain injury (TBI). The present study examined educational skills (reading accuracy, spelling and arithmetic) at a mean follow-up interval of 6.8 years post-injury in children who had sustained a mild, moderate, or severe TBI at two ages: ‘Young’ (age at injury: 3–7 years, n = 48) and ‘Old’: (age at injury: 8–12 years, n = 36). Comparisons between the young and old TBI groups resulted in inconsistent findings. While a dose-response relationship for severity was evident for the young group, this was not always the case for the old group. Significant predictors of outcome included both severity and acute intellectual function.  相似文献   
102.
PurposeThe purpose of this study was to simulate treatment planning source positioning errors in transrectal ultrasound–based real-time high-dose-rate prostate brachytherapy treatments and determine appropriate in vivo source tracking error thresholds.Methods and MaterialsTreatment planning source positioning errors were simulated for 20 patient plans in the brachytherapy treatment planning system by manually adjusting the dwell position coordinates within selected catheters without plan reoptimization. The change in dose-volume histogram (DVH) indices was calculated as a function of the source positioning error. The magnitude of the change in the DVH indices was then used to derive appropriate in vivo source tracking error thresholds.ResultsSource positioning error thresholds to prevent potentially significant changes in prostate (target) DVH metrics ranged from 2 to 5 mm, dependent on the direction of the source positioning error, as well as the relative weight of the dwell position within the plan, and its position relative to the patient anatomy. Source positioning error thresholds to prevent potentially clinically significant changes in organ at risk DVH metrics were found to be complex and patient-dependent.ConclusionsIn vivo source tracking error thresholds for transrectal ultrasound–based real-time high-dose-rate prostate brachytherapy were investigated via the simulation of treatment planning source positioning errors. These error thresholds were found to be dependent not only on the direction of the error, but also on the endpoint. There is still the potential for larger changes in DVH indices to occur for catheter shifts smaller than the proposed threshold levels in this study.  相似文献   
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OBJECTIVE: While a small number of research papers have reported findings on attentional deficits following pediatric traumatic brain injury (TBI), no study to date has reported findings in this area at 5 years post-TBI in very young children. This study examined attentional skills in a group of children who had sustained a mild, moderate, or severe TBI between the ages of 2 and 7 years. METHODS: The sample comprised 70 children, 54 of these had sustained a TBI and 16 the non-injured control group. Children were assessed 5 years post-TBI, with focus on tests of attentional ability. RESULTS: Attentional and processing speed (PS) deficits do occur and persist up to 5 years post-TBI, particularly following severe TBI in early childhood. Predictors of attentional outcomes varied depending on the component of attention investigated. CONCLUSIONS: Those skills developing or emerging at time of injury (e.g., sustained attention, shifting attention, divided attention, PS) are more compromised and may not develop at a normal rate of post-injury.  相似文献   
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Summary Oral glucose, i.v. tolbutamide and i.v. arginine tolerance tests were performed in 11 patients with myotonic dystrophy and 9 of their clinically unaffected relatives. Five of the myotonic patients had glucose intolerance; 7 had exaggerated immunoreactive insulin (IRI) response to glucose. One of the 9 relatives demonstrated glucose intolerance and none had exaggerated insulin response to glucose. Three relatives, all obese, hyperresponded to arginine and one of them also responded excessively to tolbutamide. The results indicate that an exaggerated IRI response to glucose is common in myotonic dystrophy. Enhanced responses to other stimuli are less frequent. Although glucose intolerance occurred in half of the patients, the fact that the highest IRI levels were seen in non-diabetic patients suggests that this excessive response may protect against glucose intolerance. Our studies in relatives do not support the potential usefulness of testing for hyperinsulinemia in the early detection of myotonic dystrophy. Presented at the 9th International Diabetes Federation Congress in New Delhi, India, November 2, 1976.  相似文献   
108.
We have introduced the rat growth hormone gene into mouse fibroblasts via a retroviral DNA vector. The ability of the viral DNA to induce foci in the recipient cells was used as a dominant selection marker. Several copies of rat growth hormone DNA were integrated in the mouse cells. The transformed mouse cells expressed rat growth hormone-specific mRNA and secreted mature rat growth hormone. In rat cells, the expression of this gene is regulated by glucocorticoids. We demonstrate that hormone-dependent regulation transfers with the clone and thus appears to be an intrinsic property of the gene or its RNA products.  相似文献   
109.
OBJECTIVE: To assess the usefulness of magnetic-resonance imaging (MRI) for monitoring acute changes after angioplasty of preexisting lesions in rabbits with basal lesions similar to those observed in humans. METHODS: A combination of Fogarty balloon injury (1 week after initiation of diet) and a mildly hypercholesterolemic diet (0.2% cholesterol and 5% peanut oil) was used to promote the rapid formation of atherosclerotic lesions in 16 New Zealand white rabbits. After 5 months of the diet, angioplasty was performed on these lesions with a Grüntzig catheter in both iliac arteries and the abdominal aorta. MRI was used to monitor the initial formation of lesions after 3 and 5 months of the diet, and 2 days, 2 weeks, and 1 and 2 months after angioplasty. RESULTS: The combination of early Fogarty injury and mildly hypercholesterolemic diet induced fibroproliferative lesions similar to type Vb atherosclerotic lesions seen in humans. Angioplasty induced deep dissections at the shoulders of lesions in the majority of animals. These dissections often extended into the media. The cellular, proliferative response after angioplasty was localized and limited to sites of dissection. A significant increase in area of arterial wall was observed after angioplasty at sites of dissection without any loss of lumen. In contrast, proximal and distal to the sites of injury, there was no change in wall area but a transient reduction in lumen area. CONCLUSIONS: Comparison of MRI results with histology confirmed that changes in the wall and lumen, including small linear dissections in the lesions and arterial remodeling, are detectable by MRI.  相似文献   
110.
A thorough understanding of the early natural history of cystic fibrosis (CF) lung disease is critical for the development of effective interventions in the youngest patients. We assessed the evolution of pulmonary infection, inflammation, and clinical course among 40 infants over a 2-year period through annual bronchoalveolar lavage (BAL) for culture and measurements of pro- and anti-inflammatory cytokines, semiannual infant pulmonary function testing, and quarterly clinical evaluations. Both the prevalence of CF pathogens and their density in BAL fluid increased with age. Infants had neutrophilic lower airway inflammation and elevated IL-8 concentrations independent of whether CF pathogens were recovered. Total leukocyte and neutrophil densities and IL-8 concentrations increased with density of CF pathogens in BAL fluid, whether the isolated organism was P. aeruginosa or another pathogen. IL-10 concentrations were similar in CF subjects and non-CF historical controls. Infants generally had suboptimal growth (low weight and height percentiles) and obstructive lung disease (decreased expiratory flows and air trapping). Subjects from whom CF pathogens were isolated at > 10(5) cfu/mL had the worst air trapping and lowest Brasfield chest X-ray scores. Our findings provide a foundation for future studies of early intervention in CF lung disease, including antimicrobial and anti-inflammatory therapy.  相似文献   
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