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21.
In vitro measurements of os calces and trabecular bone samples have been carried out using broadband ultrasonic attenuation (BUA) and quantitative computed tomography (QCT). The correlation between the measurements was 0.92 and 0.86 for the heelbones and the trabecular samples respectively, and the QCT and BUA correlated equally well with the physical density of the samples, indicating that the new ultrasonic technique is potentially useful for the evaluation of trabecular bone for the diagnosis of osteoporosis.  相似文献   
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A 60-year-old man with a history of prostatic carcinoma presented with left lower extremity swelling. A massively distended urinary bladder produced a false-positive radionuclide venogram.  相似文献   
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Assessment of broadband ultrasound attenuation in the os calcis in vitro   总被引:1,自引:0,他引:1  
1. We have examined the relationship between the attenuation of broadband ultrasound in the os calcis in vitro and its bone mineral density measured by quantitative computed tomography and by physical density. 2. Broadband ultrasound attenuation was found to correlate closely with physical density (r = 0.85, P less than 0.0001), but the correlation was less than that observed between quantitative computed tomography and physical density (r = 0.92, P less than 0.0001). Measurements of broadband ultrasound attenuation and quantitative computed tomography were significantly correlated (r = 0.80, P less than 0.0001). 3. Partial correlation analysis showed a significant relationship between broadband ultrasound attenuation and bone density, but when the effect of physical density was taken into account no significant correlation was found between broadband ultrasound attenuation and quantitative computed tomography (r = 0.08, not significant). 4. Broadband ultrasound attenuation in three prospective amputees showed a high degree of concordance between measurements in vivo and in vitro, with no interference by surrounding soft tissues. 5. The correlation between physical density and broadband ultrasound attenuation was independent of quantitative computed tomography, suggesting that the technique measures aspects of density which differ from its mineral density. Broadband ultrasound attenuation holds promise as a reproducible, rapid, radiation-free assessment of skeletal status.  相似文献   
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OBJECTIVE: The objective of this original report is to describe the characteristic chest imaging findings in children with primary congenital pulmonary lymphangiectasia who survive infancy. CONCLUSION: In children with primary congenital pulmonary lymphangiectasia, increased interstitial markings decrease over time and increased hyperinflation is associated with persistent patchy areas of ground-glass opacity.  相似文献   
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BACKGROUND: Preimplantation genetic screening (PGS) is used to determine the chromosome status of human embryos from patients with advanced maternal age (AMA), recurrent miscarriage (RM) or repeated implantation failure (RIF). METHODS: Embryos from 47 such couples were investigated for chromosomes 13, 15, 16, 18, 21 and 22 using fluorescence in situ hybridization with two rounds of hybridization. The investigation included parental lymphocyte work-up, the screening of blastomeres on day 3 and full follow-up on day 5/6 of untransferred embryos. RESULTS: The outcome of 60 PGS cycles is described, in which 523 embryos were biopsied; 91% gave results, of which 18% were diploid for all the chromosomes tested and 82% were abnormal. The pregnancy rate per cycle that reached the biopsy stage was 27%, and 30% per embryo transfer. Satisfactory follow-up was obtained from 353 embryos; all those diagnosed as abnormal were confirmed as such, although two false-positives were detected in relation to specific chromosome abnormalities. Meiotic errors were identified in 16% of embryos. Between the RM, AMA and RIF groups, there was a significant difference in the distribution of embryos that were uniformly abnormal and of those with meiotic errors; with an almost 3-fold increase in meiotic errors in the first two groups compared with the RIF group. CONCLUSIONS: This complete investigation has identified significant differences between referral groups concerning the origin of aneuploidy in their embryos.  相似文献   
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