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Background : A patient with a solitary pulmonary metastasis who had breast cancer in the past may benefit from pulmonary resection. Methods : Between 1984 and 1996, 17 patients underwent metastatectomy for metastatic breast cancer. There were 15 females and two males whose average age was 59 (range: 40–74 years). The median tumour-free interval after the primary breast-cancer operation was 5.1 years (range: 8 months-18.2 years). Sixteen patients had complete resections, which included six lobectomies and 10 lesser resections. Results : The postoperative mortality was nil and the morbidity rate was 6%. Follow-up was complete in all patients. Recurrent disease developed in four patients and two patients died of their disease. The 5-year survival was 62%. Conclusion : An aggressive surgical approach is warranted in patients with isolated resectable pulmonary metastases from breast cancer.  相似文献   
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The presence of depression was evaluated in a cross-section of 50 outpatients with dementia using the self-rated Geriatric Depression Scale and the clinician-rated Cornell Depression Scale. Impaired insight, as manifested by unawareness of dementia, correlated with dementia severity and discriminated a group of patients in whom the self-rated scale failed to show evidence of depression. Discrepancy between the two types of scales occurred among mildly as well as moderately demented patients when insight was impaired. Recognition of this discrepancy suggests that reliance on self-ratings may underestimate the presence and degree of depression among patients with dementia.  相似文献   
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Analysis of in vivo short TE 1H spectra is complicated by broad baseline signal contributions and resonance line-shape distortions. Although the assumptions of ideal metabolite resonance line-shapes and slowly varying baseline signals can be used to separate these signals, the presence of broad or asymmetric line-shapes can invalidate this model. More complex line-shape models are computationally expensive or difficult to constrain, particularly for the low signal-to-noise commonly found for in vivo MR spectroscopic imaging applications. In this study, two time-domain models for fitting variable spectral line-shapes are examined, one using B-splines and another using summed sinusoids. The methods were verified using both phantom and human data, and Monte Carlo simulations were used to evaluate variations in calculated metabolite amplitudes due to interactions between the baseline and line-shape estimations. Additional studies investigated the use of prior line-shape information, obtained from either a water MRSI measurement or calculations from B(0) maps, to determine parameter starting values or optimization constraints. Both line-shape models showed the ability to fit the variety of line-shapes present in both the phantom and human MRSI data, with similar or improved accuracy over a Gaussian line-shape model; however, this improvement resulted in only minor improvement for the high-SNR phantom data and moderate improvements in regions with asymmetry for the fitted in vivo metabolite images. The use of prior line-shape information was of most benefit when applied toward setting optimization constraints but was of limited benefit when used to define initial starting values.  相似文献   
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The most common types of barrier membranes used for bone or tissue regeneration are made of expanded-polytetrafluoroethylene (e-PTFE) or resorbable materials, such as collagen. Both the e-PTFE and resorbable membranes require primary soft tissue coverage. This article explores the use of a dense-polytetrafluoroethylene (d-PTFE) membrane, which does not require primary soft tissue coverage. The advantages of d-PTFE in contrast to the other more commonly used types of barrier membranes and the clinical significance of these advantages for implant surgical and restorative treatment are discussed.  相似文献   
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