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61.
The use of multiple sites for the diagnosis of osteoporosis 总被引:1,自引:4,他引:1
J. A. Kanis O. Johnell A. Oden H. Johansson J. A. Eisman S. Fujiwara H. Kroger R. Honkanen L. J. Melton III T. O’Neill J. Reeve A. Silman A. Tenenhouse 《Osteoporosis international》2006,17(4):527-534
Introduction It has been suggested that bone mineral density (BMD) measurements should be made at multiple sites, and that the lowest T–score
should be taken for the purpose of diagnosing osteoporosis.
Purpose The aim of this study was to examine the use of BMD measurements at the femoral neck and lumbar spine alone and in combination
for fracture prediction.
Methods We studied 19,071 individuals (68% women) from six prospective population-based cohorts in whom BMD was measured at both sites
and fracture outcomes documented over 73,499 patient years. BMD values were converted to Z-scores, and the gradient of risk
for any osteoporotic fracture and for hip fracture was examined by using a Poisson model in each cohort and each gender separately.
Results of the different studies were merged using weighted β-coefficients.
Results The gradients of risk for osteoporotic fracture and for hip fracture were similar in men and women. In men and women combined,
the risk of any osteoporotic fracture increased by 1.51 [95% confidence interval (CI)=1.42–1.61] per standard deviation (SD)
decrease in femoral-neck BMD. For measurements made at the lumbar spine, the gradient of risk was 1.47 (95% CI=1.38–1.56).
Where the minimum of the two values was used, the gradient of risk was similar (1.55; 95% CI=1.45–1.64). Higher gradients
of risk were observed for hip fracture outcomes: with BMD at the femoral neck, the gradient of risk was 2.45 (95% CI=2.10–2.87),
with lumbar BMD was 1.57 (95% CI=1.36–1.82), and with the minimum value of either femoral neck and lumbar spine was 2.11 (95%
CI=1.81–2.45). Thus, selecting the lowest value for BMD at either the femoral neck or lumbar spine did not increase the predictive
ability of BMD tests. By contrast, the sensitivity increased so that more individuals were identified but at the expense of
specificity. Thus, the same effect could be achieved by using a less stringent T–score for the diagnosis of osteoporosis.
Conclusions Since taking the minimum value of the two measurements does not improve predictive ability, its clinical utility for the diagnosis
of osteoporosis is low. 相似文献
62.
Background: Spaced retrieval training has been used to teach individuals with dementia to use compensatory memory strategies. This training has been delivered over the telephone to some persons with dementia. Spaced retrieval applications for individuals with traumatic brain injury have not been reported to date.Aims: The purpose of this study was to investigate the efficacy of spaced retrieval for teaching individuals with traumatic brain injury strategies and facts via the telephone, with an emphasis on generalisation.Methods & Procedures: Seven participants with chronic everyday memory problems due to traumatic brain injury were trained to use memory aids for prospective and episodic memory tasks. Participants demonstrated borderline normal to mild global severity ratings. Functional memory problems were identified and external memory aids were provided if appropriate. Participants were trained using spaced retrieval via the telephone 30 minutes per day; each participant was trained on three memory goals. Participants and some caregivers reported strategy use and generalisation for most trained goals.Outcomes & Results: Results indicated that goal attainment and generalisation were achieved in an average of five 30-minute training sessions, resulting in 94.4% spaced-retrieval goal maintenance at 1 month. Strategy execution at 1 month was reported on 77.7% of goals trained.Conclusions: Spaced retrieval is a viable approach for training individuals with traumatic brain injury to use external memory aids and learn prospective memory tasks. Telephone intervention should be considered as an accessible service delivery alternative to promote generalisation with this population. 相似文献
63.
64.
Does Bone Density Predict Fractures Comparably in Men and Women? 总被引:2,自引:0,他引:2
65.
66.
GB Fogarty R Cassumbhoy JM Martin M Fay J Ainslie 《Journal of Medical Imaging and Radiation Oncology》2007,51(3):267-275
High‐risk skin cancer arising on the upper limb or trunk can cause axillary nodal metastases. Previous studies have shown that axillary radiotherapy improves regional control. There is little published work on technique. Technique standardization is important in quality assurance and comparison of results especially for trials. Our technique, planned with CT assistance, is presented. To assess efficacy, an audit of patients treated in our institution over a 15‐month period was conducted. Of 24 patients treated, 13 were treated with radical intent, 11 with this technique. With a follow up of over 2 years, the technique had more than a 90% (10/11) regional control in this radical group. Both of the radical patients who were not treated according to the technique had regional failure. One case of late toxicity was found, of asymptomatic lymphoedema in a radically treated patient. This technique for axillary radiotherapy for regional control of skin cancer is acceptable in terms of disease control and toxicity as validated by audit at 2 years. 相似文献
67.
68.
Gautam U Mehta Sharon B Shively Heng Duong Maxine GB Tran Travis J Moncrief Jonathan H Smith Jie Li Nancy A Edwards Russell R Lonser Zhengping Zhuang Marsha J Merrill Mark Raffeld Patrick H Maxwell Edward H Oldfield Alexander O Vortmeyer 《Neoplasia (New York, N.Y.)》2008,10(10):1146-1153
Inactivation of the von Hippel-Lindau (VHL) gene and activation of the hypoxia-inducible factor (HIF) in susceptible cells precedes formation of tumorlets and frank tumor in the epididymis of male VHL patients. We performed detailed histologic and molecular pathologic analysis of tumor-free epididymal tissues from VHL patients to obtain further insight into early epididymal tumorigenesis. Four epididymides from two VHL patients were serially sectioned to allow for three-dimensional visualization of morphologic changes. Areas of interest were genetically analyzed by tissue microdissection, immunohistochemistry for HIF and markers for mesonephric differentiation, and in situ hybridization for HIF downstream target vascular endothelial growth factor. Structural analysis of the epididymides revealed marked deviations from the regular anatomic structure resulting from impaired organogenesis. Selected efferent ductules were represented by disorganized mesonephric cells, and the maldeveloped mesonephric material was VHL-deficient by allelic deletion analysis. Furthermore, we observed maldeveloped mesonephric material near cystic structures, which were also VHL-deficient and were apparent derivatives of maldeveloped material. Finally, a subset of VHL-deficient cells was structurally integrated in regular efferent ductules; proliferation of intraductular VHL-deficient cells manifests itself as papillary growth into the ductular lumen. Furthermore, we clarify that that there is a pathogenetic continuum between microscopic tumorlets and formation of tumor. In multiple locations, three-dimensional reconstruction revealed papillary growth to extend deeply into ductular lumina, indicative of progression into early hamartoma-like neoplasia. We conclude epididymal tumorigenesis in VHL disease to occur in two distinct sequential steps: maldevelopment of VHL-deficient mesonephric cells, followed by neoplastic papillary proliferation. 相似文献
69.
The venous stasis syndrome after deep venous thrombosis or pulmonary embolism: a population-based study 总被引:7,自引:0,他引:7
Mohr DN Silverstein MD Heit JA Petterson TM O'Fallon WM Melton LJ 《Mayo Clinic proceedings. Mayo Clinic》2000,75(12):1249-1256
OBJECTIVES: To estimate the incidence and determine predictors of venous stasis syndrome and venous ulcers after deep venous thrombosis and pulmonary embolism. PATIENTS AND METHODS: This population-based retrospective cohort study reviewed medical records of 1527 patients with incident deep venous thrombosis or pulmonary embolism between 1966 and 1990. We recorded baseline characteristics, event type (deep venous thrombosis with or without pulmonary embolism or pulmonary embolism alone), leg side and site of deep venous thrombosis (proximal with or without distal deep venous thrombosis vs distal deep venous thrombosis alone), and venous stasis syndrome and venous ulcer. RESULTS: Two hundred forty-five patients developed venous stasis syndrome. One-year, 5-year, 10-year, and 20-year cumulative incidence rates were 7.3%, 14.3%, 19.7%, and 26.8%, respectively. By 20 years the cumulative incidence of venous ulcers was 3.7%. Patients with deep venous thrombosis with or without pulmonary embolism were 2.4-fold (95% confidence interval, 1.7-fold-3.2-fold) more likely to develop venous stasis syndrome than patients with pulmonary embolism and no diagnosed deep venous thrombosis. In patients aged 40 years or younger with proximal compared with distal-only deep venous thrombosis, venous stasis syndrome was 3.0-fold more likely (95% confidence interval, 1.6-fold-4.7-fold). In patients with unilateral leg deep venous thrombosis, venous stasis syndrome usually developed in the concordant leg (P < .001). There was a 30% (95% confidence interval, 2%-62%) increased risk for venous ulcer per decade of age at the incident venous thromboembolism. CONCLUSIONS: The cumulative incidence of venous stasis syndrome continues to increase for 20 years after venous thromboembolism. Pulmonary embolism alone is less likely to cause venous stasis syndrome. 相似文献
70.
SK Bhattacharya MK Bhattacharya B Manna D Dutta A Deb P Dutta AG Goswami A Dutta S Sarkar A Mukhopadhaya T Krishnan TN Naik GB Nair 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(2):160-164
In a case-control study to understand the risk factors for development of life-threatening dehydration, a total of 379 children comprising 243 cases (moderate or severe dehydration) and 136 controls (non or mild dehydration) up to 2 years of age suffering from acute watery diarrhoea were studied. By univariate analysis, the presence of vibrios in stool, withdrawal of breast feeding during diarrhoea, not giving fluids, including oral rehydration solution (ORS), during diarrhoea, frequent purging (> 8/ day), vomiting (> 2/day) and undernutrition were identified as risk factors. However, by multivariate analysis after controlling for confounders, withdrawal of breast feeding during diarrhoea (odds ratio (OR) = 6.8, p < 0.00001) and not giving ORS during diarrhoea (OR = 2.1, p < 0.006) were identified as significant risk factors. The confounding variables which also contributed significantly to increasing the risk were age (≤ 12 months; OR = 2.7, p = 0.001), frequent purging (> 8/day; OR = 4.1, p < 0.00001), vomiting (> 2/day; OR = 2.4, p = 0.001) and severe undernutrition (%median <60 weight-for-age of Indian Academy of Paediatrics classification; OR = 3.1, p = 0.001). We feel that these findings will be useful for Global and National Diarrhoeal Diseases Control Programmes for formulating intervention strategies for preventing death due to diarrhoeal dehydration. 相似文献