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1.
Summary The quantity of protein and carbohydrate comprising the matrix of calcium oxalate monohydrate (COM) renal stones was found to decrease with distance from the surface of the stone. The average organic concentration of stones 3 to 30 mm in diameter ranged from 5.7% at the surface to 2.7% at the core. This concentration gradient suggests matrix involvement in a “growth front” on stone surfaces with migration of organic material from the “older” interior. The matrix distribution was not readily correlated with density variations or with the presence of hydroxyapatite or calcium oxalate dihydrate. Surface matrix concentrations were greater than amounts predicted by physical adsorption. Electron microscopy confirmed the presence of the organic-rich surface layer and also suggested that increase in stone size occurs predominantly by crystal growth with microcrystal aggregates as growth centers.  相似文献   
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Coronary artery bypass grafts: visualization with MR imaging   总被引:1,自引:0,他引:1  
Gomes  AS; Lois  JF; Drinkwater  DC  Jr; Corday  SR 《Radiology》1987,162(1):175
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Multiple sclerosis (MS) is a chronic, progressive neurological disease that causes demyelination of the central nervous system. Typically diagnosed in adulthood, it does not significantly reduce life expectancy. The goal of this exploratory study was to describe the health-related concerns and service needs of 27 older adults with MS, ages 55 to 81 years. Through in-depth interviews using a phenomenological approach, fear of the future was found to be a predominant concern among the participants. Within this fear, participants expressed particular concerns about experiencing further losses of mobility and independence, becoming a burden on caregivers, and having to move to a nursing home. The findings raise three major challenges for occupational therapists that include: (1) developing or modifying interventions that can enable older adults with MS to gain a sense of control over their future, (2) working with families affected by MS together with other disciplines such as psychology and social work, and (3) advocating for more and better community support options for persons with MS.  相似文献   
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The ureteral access set was used 43 times during an 18-month period between 1984 and 1985. Stones lodged throughout the ureter and in the renal pelvis were extracted with a success rate of 51 per cent. Of the upper tract strictures 92 per cent were dilated successfully. Filling defects were diagnosed in 88 per cent of the cases. Foreign bodies were retrieved, Double-J stents were placed and biopsies were successful in each case. Ureteral perforation in 28 per cent of the cases was caused by the dilator in 8 of 12 (19 per cent over-all). The technique and short-term results are discussed. Long-term followup data are not yet available.  相似文献   
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