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A sample consisting of 1135 edentulous patients with clinically healthy denture bearing areas, was examined radiologically. It appears that the diagnostic yield is high whereas the expected radiation induced risk is low. Patients should therefore be examined radiologically prior to full denture construction.  相似文献   
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Women's time: a factor in the use of child survival technologies?   总被引:1,自引:0,他引:1  
Time allocation studies show that women in developing countriesface severe time constraints. However, such studies give a lessclear picture of the time women spend on health and child carein the home and utilization of health services because theseare primarily sporadic, not daily, activities. Reporting timespent by women on illness or health care utilization as a dailyaverage masks the true cost of periodically losing half of aday or more of work time. Almost no direct empirical data have been gathered on the timecosts to women of breastfeeding, immunizations, ORT, or growthmonitoring, nor on whether time costs are an important determinantof utilization of these technologies. Specific research designedaround the introduction of child survival projects, plus theinclusion of appropriate measures in the evaluations of ongoingprojects, could fill this gap. Even without further research,recognition of the time constraints faced by low-income mothersin conjunction with lessons learned from successful growth monitoringand immunization projects suggests that outreach efforts maybe an important key to increasing utilization of child survivaltechnologies.  相似文献   
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A randomized prospective study was undertaken to compare the electrical performances of three permanent, endocardial, tined pacing leads with different electrode designs--sintered platinum, vitreous carbon, and porous carbon. Ninety-nine patients received one of the leads (S80 31; 423S 32; S100 36). Acute R wave amplitude and ST elevation of the native endocardial electrogram, voltage threshold, impedance, and current flow at four pulse durations (0.25-1.0 msec) were measured. Voltage thresholds were measured noninvasively at each of four pulse durations at 2 days and 1, 3, and 6 months after implantation. No significant differences were found in sensing properties, or current flow at threshold at 0.5 msec pulse duration. The 423S lead had a significantly higher impedance at threshold and both a higher impedance and lower current flow at 5 V. No significant differences in threshold voltages were found between the three leads at any pulse duration, at any of the assessed times after implantation. Six-month thresholds for the S80, 423S, and S100 leads were 1.18 +/- 0.35, 1.17 +/- 0.29, and 1.06 +/- 0.38 V respectively at 0.5 msec pulse duration. Differences between 'high performance' pacing leads need to be of a greater order of magnitude before they can be exploited to give any real clinical advantage to patients.  相似文献   
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A 47-year-old man with persistent severe oropharyngeal ulceration developed a high-grade T-cell lymphoma soon after commencing treatment with cyclosporin A. Using Southern blotting to identify T-cell beta-chain gene rearrangements, evidence of clonal restriction was found both in blood and lymph node DNA samples. Two BamH1 rearranged bands were demonstrated in both samples. In the blood a 16 Kb band predominated, with a weaker 28 kb band. In the lymph node sample this pattern was reversed. The findings suggest that a bi-clonal population of T-lymphocytes or clonal evolution of an existing T-cell monoclone had developed, and that cyclosporin contributed to the emergence of a high-grade T-cell lymphoma.  相似文献   
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