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21.
OBJECTIVE: To determine the location in soft tissues of the calcifications, similar to calcified carotid atheromas, that can be observed radiographically in the cervical region in panoramic radiographs. STUDY DESIGN: In each anatomic cadaver specimen preserved in formol, consisting of the head and neck, radiopaque spheres (made from gutta-percha) were positioned in anatomic structures of the cervical region that can be sites of calcification. For each anatomic structure marked in this way, panoramic radiography was performed, consisting of 17 radiographs. The images obtained were analyzed by 24 examiners who indicated which radiographs, in their opinion, presented the radiopaque reference projected in the region of bifurcation of the carotid artery. Analysis of 2 proportions from agreement and disagreement was used to determine radiopacities that could be confused in panoramic radiographs with calcified atheromas in the carotid artery. RESULTS: The results showed that 75% (18) of the examiners correctly indicated the reference in the bifurcation of the carotid artery and 79.2% (19) indicated a triticeous cartilage as calcified atheroma of the carotid artery. CONCLUSIONS: Calcified atheromas of the carotid artery are not the only features that can produce radiopaque images lateral to the panoramic radiograph; the presence of calcification in the triticeous cartilage also can induce an erroneous diagnosis of calcified carotid atheroma.  相似文献   
22.
A survey of 402 normal subjects (203 men, 199 women) was conducted to assist in distinguishing potential differences in norms of hand strength. Norm data had previously been collected from mixed occupational groups, but in the present study it was hypothesised that people involved in heavy manual work on a daily basis might possess greater hand strength than others. The volunteers were adults working in industry and agriculture; they were subdivided into occupational categories. Measurements of grip, key and palmar pinch using the Jamar dynamometer and B and L pinch gauge were collected, using the protocol described by Mathiowetz. Volunteers also rated their individual hand strength job requirements subjectively. Mean values were established with regard to age, sex, dominance, occupational group and subjective rating. Significant differences were found with regard to age and sex but not to dominance; there was no evidence of differences between occupational groups or between subjective rating and individual scoring, i.e. volunteers who perceived their job as requiring a high degree of strength did not achieve higher test measurements than others. A high interrater reliability was demonstrated when comparing these follow-up measurements with the original data. It was concluded that, for clinical and rehabilitative purposes, therapists can interpret assessment of outcome most accurately by comparing patients' results with the existing norm data.  相似文献   
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BACKGROUND: Color Doppler ultrasonography of intrarenal arterial resistance index (RI), performed early after kidney transplant, has proven to reliably predict short-term allograft function. The aim of this study was to assess whether it could also predict long-term renal function. METHODS: We retrospectively analysed 76 kidney transplant patients who underwent RI assessment within 1 month after the transplant, subdivided into two groups according to RI values, lower (group A) or higher (group B) than its median value (0.635). RESULTS: Compared with group A subjects, the patients of group B were older at the time of transplant (42 +/- 9 vs 35 +/- 8 years; P = 0.001), the donor age was also older (41 +/- 16 vs 33 +/- 13 years; P = 0.02) and had a slightly higher proteinuria (0.54 +/- 0.5 vs 0.32 +/- 0.2 g/24 h; P = 0.02). Serum creatinine, ciclosporin or tacrolimus trough level, arterial blood pressure, number of human leukocyte antigen (HLA) mismatches, anti-hypertensive medications and incidence of delayed graft function were not significantly different between the two groups. By univariate analysis, RI turned out to directly correlate with the recipient age, donor age and daily proteinuria (P = 0.007, P = 0.0007 and P = 0.02, respectively). Multivariate analysis showed that only donor and recipient age maintained their independent predictive value on RI. Kaplan-Meier analysis, considering a serum creatinine increase >50% as the endpoint of the study, showed a statistically significant different graft survival in the two groups (log-rank test = 5.489; P = 0.01). The univariate relative risk of deterioration of graft function among patients with higher RI was 3.77. Proteinuria and recipient age increased the risk as well. CONCLUSIONS: Our data seem to suggest that early determination of RI can help predict long-term graft function in kidney transplant recipients.  相似文献   
25.
Dual-energy X-ray absorptiometry (DXA) and quantitative ultrasound (QUS) are the accepted modalities for the evaluation of fracture risk in the clinical setting. However, neither method provides a direct measurement of bone mechanics. In this study, we investigated a prototype device, known as a mechanical response tissue analyzer (MRTA), which provides direct mechanical measurements of mechanical properties of bone. A total of 56 healthy volunteers (20 men and 36 women) between the ages of 18 and 83 were recruited. The MRTA was used to measure the cross-sectional bending stiffness (EI) of the ulna bone. Axial speed of sound (SOS) at the ulna bone was determined by QUS; bone mineral content (BMC) and bone mineral density (BMD) were determined by DXA. Correlations, regression analysis, and analyses of variance (ANOVAs) were used to compare the three modalities. These analyses revealed that although there are strong linear relationships among the data collected by the various technologies, the bone properties reflected by MRTA are not fully explained by DXA and QUS. We conclude that the total information conveyed by MRTA measurements is unique. Further research is needed to delineate the different qualities of bone strength that are captured by MRTA, but not by DXA or QUS.  相似文献   
26.
BACKGROUND: Delays in seeking treatment for signs and symptoms of acute myocardial infarction are longer for African Americans than for whites. OBJECTIVE: To determine factors associated with prolonged delay and the extent to which perceived racism influences prehospital delay in African Americans with acute myocardial infarction. METHODS: Sixty-one African Americans with acute myocardial infarction were interviewed within 1 month of hospital admission. Delay times were calculated on the basis of the interviews. Independent t tests and chi(2) tests were used to determine factors associated with prolonged delays. RESULTS: Median delay was 4.25 hours and did not differ significantly between women and men (4.42 vs 3.50 hours). Most patients (69%) experienced their initial signs and symptoms at home, often witnessed by family members or friends (70%). Delay was longer for insured patients than for uninsured patients (4.45 vs 0.50 hours). Single, widowed, or divorced patients had longer delay times than did married patients (5.33 vs 2.50 hours), and patients with diabetes delayed longer than did those without diabetes (7.29 vs 3.50 hours). Perceived racism did not differ significantly between patients who delayed seeking treatment and those who did not. CONCLUSIONS: Median delay times were substantially longer than the recommended time of less than 1 hour, reducing the benefit from reperfusion therapies. Education and counseling of patients and their families should be a major strategy in optimizing patients' outcomes and decreasing the time to definitive treatment.  相似文献   
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BACKGROUND: Psychological morbidity after an acute myocardial infarction (AMI) is known to be common, but can be addressed by appropriate rehabilitation. The area in which this research was conducted experiences high rates of deprivation and of coronary heart disease and limited access to hospital-based rehabilitation. Responding to concern about psychological needs of AMI patients, a self-help package was introduced and evaluated alongside standard hospital-based cardiac rehabilitation. AIMS: To evaluate the impact of a home-based self-help package (the Heart Manual), alongside existing cardiac rehabilitation provision, on psychological morbidity and health status after AMI. A secondary aim was to assess the suitability of the Heart Manual for older patients aged over 80 years. METHODS: A controlled observational study, comparing two cohorts of patients discharged from hospital after AMI. The intervention group was given the self-help package in addition to standard care. The control group received standard care alone. Outcome measures used were the Hospital Anxiety and Depression Scale and the EuroQol. RESULTS: The intervention group showed significant improvement in anxiety and depression scores after 3 months and nonsignificant improvement in general health status. Patients who attended hospital-based rehabilitation classes, and those aged over 80 years, also benefited from the intervention. CONCLUSION: A home-based self-help rehabilitation package is an effective tool alongside hospital-based rehabilitation classes and can be given to all age groups.  相似文献   
29.
Repeated measures designs are often used to evaluate the effectiveness of interventions. In these designs, the outcomes are measured on several occasions before and after implementation of the intervention. Two statistical methods, the repeated measures analysis of variance (RM-ANOVA) and hierarchical linear models (HLM), can be used to analyze the data. The authors provide an overview of the statistical models underlying RM-ANOVA and HLM and discuss the strengths and limitations of each. They propose that the 2 methods are complementary in determining the effectiveness of interventions.  相似文献   
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