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991.
The endosteal hollow cylinder implant systems have been in clinical use for over 10 years. These systems incorporate advanced sophisticated biomaterials and bioengineering design concepts such as the titanium plasma spray (TPS) surface coating as well as the cylindric shape. This shape has now introduced the third dimension to dental implantology. In previous systems, such as the blade-vent, only height and width were present. Therefore, these previous systems could not be used as single-tooth replacements; also, they were not able to withstand lateral forces or torquing. In a series of cases reported from Switzerland, Sweden, Germany, and the United States, 580 hollow cylinder implants were placed for up to 10 years with an overall rate of success of 95.3 per cent.  相似文献   
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The late results--up to six years--after axillo-femoral bypass reconstruction are reported for 85 patients with leg ischaemia who were regarded as poor-risk patients for aortic bypass surgery, or who had aortic graft infection. Velour-Dacron grafts and expanded polytetrafluoroethylene (PTFE, Gore-Tex)--grafts have been used. The cumulative patency rate (life table) six years after graft implantation was 64% (PTFE-grafts) and 58% (Velour-Dacron grafts). The corresponding cumulative limb salvage rate six years after graft implantation was 88% when PTFE grafts were used and 77% when Velour-Dacron grafts were used. Our results demonstrate that axillo-femoral reconstruction is a useful procedure with a good patency rate 6 years after implantation. This procedure should be considered when dealing with poor risk patients with severe leg ischaemia.  相似文献   
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Simultaneous recording of the spirogram, pneumotachogram and transpulmonary pressure as well as total plethysmography were applied in 30 patients with bronchial asthma to study the respiratory ventilation and mechanism before and after single procedures of acupuncture. The bronchodilatory action of acupuncture has been proved, related, in particular, with a significant decrease of non-elastic resistance of the lungs. At the same time pronounced changes in the elastic resistance were noted. However, they appeared to be of different directions. The improvement of ventilatory function was determined not only by a decrease in the intrapulmonary resistance but also by shifts in respiratory regulation and in the activity of the respiratory musculature, confirmed by an analysis of the curves of the respiratory work obtained before and after acupuncture. The curative action of acupuncture in bronchial asthma cannot be adequately explained by the placebo effect.  相似文献   
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Spinal Ewing's sarcomas are rare and cause problems in differential diagnosis. The radiologic, nuclear medicine and CT findings in two children with histologically proven Ewing's sarcoma are presented and problems in differential diagnosis discussed. Biopsy should be done early.  相似文献   
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