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Behçet’s disease is a rare disease characterised by recurrent oral ulcers, with systemic manifestations including genital ulcers, ocular disease, skin lesions, gastrointestinal disease, neurologic disease, vascular disease and arthritis. Most clinical manifestations of Behçet’s disease are believed to be due to vasculitis. The heterogeneous clinical spectrum is influenced by sex, ethnicity and country of residence. Vascular manifestation in the form of isolated large brachial artery aneurysm is rare in children. Treatment involves aneurysmorrhaphy to avoid rupture or ischaemic sequelae in addition to lifelong medical management to control vasculitis.  相似文献   
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Summary The use of three‐dimensional (3D) models of the dentition obtained from cone beam computed tomography (CBCT) is becoming increasingly more popular in dentistry. A recent trend is to replace the traditional dental casts with digital CBCT models for diagnosis, treatment planning and simulation. The accuracy of these models was previously assessed through comparing linear physical and radiographical measurements. However, this assessment technique is both observer and landmark dependent. The accuracy of 3D CBCT teeth reconstructions is yet to be reliably measured. To assess the accuracy of 3D CBCT reconstructions of the teeth using a semi‐automated and observer‐independent method and to assess the influence of field of view (FoV) selection on reconstruction accuracy. Fully dentate upper and lower dry human jaws, placed in a plastic box and immersed in water, were scanned using CBCT with small, medium and large FoV. The teeth were then scanned separately using MicroCT. Cone beam computed tomography and MicroCT 3D teeth models were compared, and mean surface difference was calculated per tooth for each FoV. Mean and (maximum) differences between MicroCT and CBCT were 120 ± 40 (max. 679) μm, 157 ± 39 (max. 824) μ and 207 ± 80 (max. 862) μm for the small, medium and large FoV, respectively. Cone beam computed tomography models were larger than MicroCT because of larger voxel size. Our results indicate that CBCT may provide accurate 3D reconstructions of the teeth that can be useful for some clinical applications.  相似文献   
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Recent studies show that vitamin A levels decrease during measles and that vitamin A therapy can improve measles outcome in children in the developing world. Vitamin A levels of children with measles have not been studied in developed countries. We therefore measured vitamin A levels in 89 children with measles younger than 2 years and in a reference group in New York City, NY. Vitamin A levels in children with measles ranged from 0.42 to 3.0 mumol/L; 20 (22%) were low. Children with low levels were more likely to have fever at a temperature of 40 degrees C or higher (68% vs 44%), to have fever for 7 days or more (54% vs 23%), and to be hospitalized (55% vs 30%). Children with low vitamin A levels had lower measles-specific antibody levels. No child in the reference group had a low vitamin A level. Our data show that many children younger than 2 years in New York City have low vitamin A levels when ill with measles, and that such children seem to have lower measles-specific antibody levels and increased morbidity. Clinicians may wish to consider vitamin A therapy for children younger than 2 years with severe measles. Additional studies of vitamin A in measles and other infectious diseases, and in vaccine efficacy trials, should be done.  相似文献   
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The extent of length polymorphisms of the heterochromatic and euchromatic segment of the human Y chromosome were investigated in 15 boys with acute leukemia and were compared with 15 normal controls. A greater value of the Yh/F index in relation to controls was established (P < 0.05). The length of the euchromatic segment was also shorter in the patients than the controls (P < 0.05).  相似文献   
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