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OBJECTIVE: The aim of our study was to evaluate the diagnostic agreement between quantitative sonography of the calcaneus and dual X-ray absorptiometry (DXA) of the spine and femur for revealing osteoporosis. SUBJECTS AND METHODS: In 1252 patients (795 women, 54.9+/-15 years old; 457 men, 50.5+/-15 years old [mean+/-SD]), bone mineral density measurements of the lumbar spine (posteroanterior, L1-L4) and the proximal femur (neck, trochanter, intertrochanteric region, total proximal femur, and Ward's triangle) and quantitative sonographic measurements of the stiffness of the calcaneus were performed. The presence of osteoporosis is defined, according to the World Health Organization criteria, as a T-score lower than -2.5. The percentage of patients below the threshold (prevalence of osteoporosis) was calculated for each imaging technique. The diagnostic agreement in identifying individuals as osteoporotic was assessed using kappa scores. RESULTS: Forty-nine percent of the women and 42% of the men were classified as osteoporotic by quantitative sonography, 32% of women and 30% of men by DXA of the spine, and 23-54% of women and 16-54% of men by the different regions of interest revealed on femoral DXA. Kappa analysis showed the diagnostic agreement among these measures to be generally poor (kappa = .28-.41 [women] and .25-.45 [men]). CONCLUSION: The considerable diagnostic disagreement between quantitative sonography and DXA could cause confusion in the daily practice of radiology and make establishing the correct diagnosis a difficult task. The choice of imaging technique influences which patients are diagnosed as osteoporotic.  相似文献   
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A large variety of approaches are described for standard total hip arthroplasty. All of them are technically based on three different approaches: anterior, anterolateral, or posterior. In recent hip resurfacing, the posterior approach is common, due to large instruments used to ream the femur. Better exposure of the acetabulum is achieved by the posterior approach, but this technique puts the important extraosseous blood supply to the femoral head at risk. The anterior approach preserves blood supply and gives better options to treat the femoroacetabular impingement. If specific surgical modifications and instruments designed for minimally invasive surgery are used, hip resurfacing can be performed with an anterolateral technique. Excellent functional and clinical outcomes have been reported after all three approaches.  相似文献   
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AIMS: To assess and compare the reliability of dynamic MRI to quantify pelvic organ prolapse (POP) according to the International Continence Society (ICS) using two different reference lines, and to determine which line gives the best concordance with clinical examination. METHODS: Forty-seven patients with genital prolapse underwent physical examination and dynamic MRI. Five nulliparous, symptom-free female volunteers underwent dynamic MRI as control subjects. Two distinct observers performed the MRI measurements of POP according to the ICS using two distinct reference lines: the mid-pubic line and a new one, the perineal line that provides a better match with the hymen plane. Measurements were repeated twice according to each line. The intra-class coefficient was used to estimate intra-observer and inter-observer reliability; the Altman and Bland plot was used to assess the agreement between MRI and clinical measurements. RESULTS: The intra-observer and inter-observer reliability of MRI measurements were in general excellent. Intra-class coefficients were better for the mid-pubic line than the perineal line. Although the MRI measurements correlate significantly with the physical measurements, the Altman and Bland plot shows an unacceptable magnitude of discrepancy between clinical and MRI examinations. CONCLUSIONS: Although dynamic MRI shows excellent inter- and intra-observer reliability, its agreement with clinical examination is poor whatever the line used.  相似文献   
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Objective: To determine the frequency of dual infection of Tuberculosis and Human Immunodeficiency Virus (HIV) and document the sexual practices of infected patients. Design: Cross-sectional study. Place and Duration of Study: Medical Unit-IV of Civil Hospital, Karachi, Pakistan, in collaboration with Sindh AIDS Control Program at Services Hospital, Karachi, from January 2003 to December 2004. Patients and Methods: Patients were recruited in the study at both centers and tested for both HIV and TB if any one disease was identified. Diagnosis of TB was based on positive sputum AFB smear / caseous granulomatous lesion on histopathology. Diagnosis of HIV was based on positive anti-HIV serology by LISA technique. A questionnaire was also administered to all the study participants regarding demographics, sexual practices, blood transfusion and intravenous drug abuse. Results: A total of 196 patients of HIV and TB were screened for the presence of dual infection (TB/HIV). Dual infection was present in 38 (19.39%) of patients. Out of 126 patients of HIV, evidence of TB was detected in 38 (30.16%). During the same duration, 70 patients of tuberculosis were screened for HIV and none was tested positive for HIV. History of illicit sexual relationship was found in 121 (96.03%) patients and 5 of these were homosexuals. Conclusion: Dual infection was present in patients of HIV with TB but vice versa was not documented in this study.  相似文献   
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<正>The health effects of climatic changes constitute an important research area, yet few researchers have reported city-or region-specific projections of temperature-related deaths based on assumptions about mitigation and adaptation. Herein, we provide quantitative projections for the number of additional deaths expected in the future, owing to the cold and heat in the city of Nanjing, China, based on 31 global circulation models(GCMs), two representative  相似文献   
38.
Fifteen patients with solid and cystic occlusions of the cerebrospinal fluid (CSF) circulation pathways were examined with MRI using an ECG retrogated two-dimensional FISP sequence to determine whether there are certain defined pathological CSF flow patterns in these patients. All patients were clinically still compensated. The results of the measurements of CSF flow velocities at different locations in the CSF system were compared with the results from 8 healthy volunteers. In all patients with occlusive processes of the intraventricular CSF pathways (4 aqueduct stenoses, 1 membranous occlusion of the fourth ventricular outlets, 1 solid tumour at the foramen of Monro and 1 solid fourth ventricular tumour) we observed hyperdynamic CSF pulsation above the lesion. This was transmitted into the spinal canal. Close by a solid occlusion within the aqueduct the flow velocity curve over the RR cycle was typically shifted, resulting in a mirroring of the flow velocity curve compared with normals. In cystic lesions (n = 4) there was transmission of the pulsation wave through the lesion and therefore no mirroring of the flow velocity curve. This technique allows very good delineation of cystic structures in the peripineal region (n = 4), also due to the opposite direction of flow within the cyst compared with the surrounding CSF spaces, depending on the extent of communication. Correspondence to: U. Kunz  相似文献   
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In this report, we describe a case of a 43-year-old male who sustained a displaced mid chondral costal cartilage fracture along with multiple ipsilateral rib fractures following a jet ski collision. Costal cartilage fractures (CC) are commonly missed on imaging evaluation, and accordingly underreported in the literature. High-energy blunt chest trauma represents the most common mechanism for CC injuries. Computed Tomography (CT) is the modality of choice to diagnose CC fractures along with the associated cardiopulmonary and abdominal injuries in polytrauma patients. There is currently no consensus with respect to the management of CC fractures. Further research is required to explore the long-term impact of CC fractures on thoracic cage stability.  相似文献   
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