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451.
Normal and degenerative posterior spinal structures: MR imaging   总被引:3,自引:0,他引:3  
A retrospective study of the magnetic resonance (MR) images of the lumbar spines of 13 healthy subjects and 30 patients with degenerative changes was done. In the healthy subjects, the vertebral facets, thickness of the cartilage and ligamentum flavum, signal characteristics of the bone marrow, and size of the spinal canal were studied. In the patients with degenerative changes in one of these structures, MR images in the sagittal plane were useful in demonstrating hypertrophy of the ligamentum flavum or the vertebral facets, in grading the degree of foraminal stenosis, and in measuring the sagittal diameter of the spinal cord. MR images in the axial plane facilitated detailed analysis of the facet joint and more accurate measurements of the thickness of the ligamentum flavum and spinal canal diameter. MR images were compared with computed tomography scans in 12 patients.  相似文献   
452.
OBJECTIVE: To assess whether efforts to actively involve General Practitioners (GPs) in the postdischarge care of their paediatric asthma patients improved their satisfaction with communication with hospital staff. METHODOLOGY: Randomized controlled trial involving 60 patients admitted to the Royal Children's Hospital, Melbourne, with acute asthma and an identifiable GP. The GPs of the intervention patients were telephoned during the admission. Intervention patients and their GPs received printed information detailing the care the patient received in hospital and the recommended postdischarge care, as well as standardized educational booklets about asthma. Follow-up appointments were made for intervention patients to attend their GPs. RESULTS: The GPs of intervention patients were more satisfied when compared to the GPs receiving a standard level of communication (96.4% vs 48.3% of the intervention and control GPs, respectively, described the communication as good or extremely good, P = 0.0001). The intervention group GPs believed they were more involved after discharge (75.0% vs 44.8%, P = 0.005) and had greater understanding of their patient's hospitalisation (96.4% vs 62.1%, P = 0.005). These differences were noted despite there being no difference in the rate of follow-up attendance with GPs for intervention and control patients (85.7% vs 72.4%, P = 0.2). Qualitative data supported these findings with GPs expressing approval of the intervention used. CONCLUSION: Efforts to actively involve GPs in the postdischarge care of their paediatric patients with asthma resulted in a marked improvement in their satisfaction with the communication with medical staff at the Royal Children's Hospital, Melbourne. The study had insufficient power to demonstrate a difference in morbidity.  相似文献   
453.
Objective : To determine the type and outcome of early post-traumatic seizures in children and the factors associated with it.
Methodology : A prospective observational study on all consecutive children with head injuries at the General Hospital Kuala Lumpur between November 1993 and December 1994. The onset, type and frequency of seizures occurring within the first week of injury were documented. Using inpatients as a cohort, logistic regression analysis was used to determine clinical and radiological variables significantly associated with seizures. The outcome 6 months post-injury was assessed using the Glasgow Outcome Scale.
Results : Fifty-three of 966 children (5.5%) developed seizures within the first week of trauma. Seven (13.2%) occurred within 1 h of injury, 30 (56.6%) between 1 and 24 h and 16 (30.2%) after 24 h. Factors significantly associated with early post-traumatic seizures were female sex, age less than 2 years, loss of consciousness for more than 24 h and acute subdural haematoma ( P <0.01). Children with seizures had a poorer outcome (death or severe disability) man inpatients without seizures (21/53 vs 19/182, P <0.001). The outcome was worst in children with recurrent partial seizures, who had a longer injury-seizure interval and were more likely to have focal neurologic deficits compared to those with sporadic or generalized seizures.
Conclusions : Anticonvulsant prophylaxis to minimize the adverse effects of early seizures in head injury should be considered for young children (less than 2 years old) with subdural haematoma and a prolonged duration of coma. Prompt and effective control of recurrent seizures is recommended.  相似文献   
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The potential value of measurements of peripheral bone mass in rheumatoid arthritis (RA) as an assessment of long-term disease activity has recently received renewed attention. This study examines the effects of RA and corticosteroid therapy on newer methods of measuring peripheral bone mass, comparing the results with dual-energy X-ray absorptiometry (DXA) at axial sites. Peripheral quantitative computed tomography of the radius, ultrasound of the calcaneus, and DXA of the hip and spine were compared between 29 controls and 46 women with RA of whom 25 were receiving low-dose corticosteroid therapy. Bone mass was significantly reduced in the RA groups for: (i) radial trabecular (36.1%) and total (15.6%) measurement sites; (ii) calcaneal ultrasound attenuation (31.7%) and velocity (6.6%); and (iii) femoral neck (15.4%) bone mineral density. Lumbar spine and radial cortical measurements were not significantly affected. There were no significant differences between the RA groups. Disease activity and physical activity did appear to be responsible for much of the reduction in bone mass. These results demonstrate that RA is associated with significant bone loss at the hip, radius and calcaneus, but not at the lumbar spine. In this small study, low-dose corticosteroids had little additional deleterious effect.   相似文献   
457.
Objective: Insulin resistance (IR) and associated metabolic abnormalities are increasingly being reported in the adolescent population. Cut-off value of homeostasis model of assessment IR (HOMA-IR) as an indicator of metabolic syndrome (MS) in adolescents has not been established. This study aimed to investigate IR by HOMA-IR in urban Indian adolescents and to establish cut-off values of HOMA-IR for defining MS.Methods: A total of 691 apparently healthy adolescents (295 with normal body mass index (BMI), 205 overweight, and 199 obese) were included in this cross-sectional study. MS in adolescents was defined by International Diabetes Federation (IDF) and Adult Treatment Panel III (ATP III) criteria. IR was calculated using the HOMA model.Results: Mean height, waist circumference (WC), waist/hip ratio (WHR), waist/height ratio (WHtR), and blood pressure were significantly higher in boys as compared to girls. The HOMA-IR values increased progressively from normal weight to obese adolescents in both sexes. Mean HOMA-IR values increased progressively according to sexual maturity rating in both sexes. HOMA-IR value of 2.5 had a sensitivity of >70% and specificity of >60% for MS. This cut-off identified larger number of adolescents with MS in different BMI categories (19.7% in normal weight, 51.7% in overweight, and 77.0% in obese subjects) as compared to the use of IDF or ATP III criteria for diagnosing MS. Odds ratio for having IR (HOMA-IR of >2.5) was highest with WHtR (4.9, p <0.0001) and WC (4.8, p <0.0001), compared to WHR (3.3, p <0.0001).Conclusions: In Indian adolescents, HOMA-IR increased with sexual maturity and with progression from normal to obese. A HOMA-IR cut-off of 2.5 provided the maximum sensitivity and specificity in diagnosing MS in both genders as per ATP III and IDF criteria.Conflict of interest:None declared.  相似文献   
458.
Magnetic resonance (MR) images of 13 patients with Paget disease were reviewed, and findings were correlated with those from computed tomographic (CT) scans, radiographs, and, in two patients, surgical biopsy. MR imaging findings correlated with CT and radiographic findings of cortical thickening, increased size of bone, and coarse thickened trabeculae. Focal or diffuse decreased signal intensity, representing dense bone, was seen on images obtained with short and long repetition times (TRs) and echo times (TEs); high-signal foci, representing fat collections, were seen on short TR/TE images; and high-signal foci, representing fibrovascular marrow in active Paget disease, were seen on long TR/TE images. Complications of Paget disease-including basilar invagination, spinal stenosis, and sarcoma--were well identified on MR images. Although MR imaging is not generally used in diagnosis of Paget disease, the disease will be encountered more frequently as more MR imaging examinations are performed. An awareness of the range of findings in Paget disease is useful in evaluating MR images of the musculoskeletal and other systems.  相似文献   
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