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A prospective clinical study with a random allocation of 47 adolescent patients to three different functional appliance groups was established and compared with an untreated control group over a 9-month period. Treatment was undertaken with either a Bionator, Twin Block, or Bass appliance. Pre- and post-treatment cephalograms were used to quantify the skeletal and dentoalveolar changes produced by the appliances and compared with those observed in the control group as a result of growth. Both the Bionator and Twin Block appliances demonstrated a statistically significant increase in mandibular length (3.9 +/- 2.7 mm; 3.7 +/- 2.1 mm, respectively) compared with the control group (P < 0.05), with an anterior movement of pogonion and point B. Highly statistically significant increases (P < 0.01) were seen in lower face heights for all the appliance groups compared with the control group. The Twin Block group showed the least forward movement of point A due to a change in the inclination of the maxillary plane. The Bionator and Twin Block groups showed statistically significant reductions in the inclination of the upper incisors to the maxillary plane (P < 0.05). The Bass group showed minimal change in the inclination of the lower labial segment to the mandibular plane. The Bionator group demonstrated the greatest proclination of the lower labial segment (4.0 +/- 3.6 degrees). Clinically important changes were measured in all the appliance groups when compared with the control group. Differences were also identified between the functional appliance groups. The Twin Block appliance and, to a lesser extent, the Bionator appeared the most effective in producing sagittal and vertical changes. 相似文献
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Linoleate, linolenate, arachidonate, docosahexenoate and six other fatty acids were major components of 24 ester preparations fed as 5% of the diet for 60 days to groups of male white rats. The experiment was designed so as to provide that all major fatty acid components were independent of each other in the sense that the intake of each was poorly correlated with the intake of any of the others. Fatty acid compositions of liver lipids were determined and were related to the composition of the diet lipids. Linolenate and docosahexaenoate contents of diet and tissue revealed the same relationships reported previously from experiments in which individual pure acid esters were added to a fat-free diet. Linoleate, when fed in lipid mixtures, was more effective in raising the linoleate concentration in liver lipids than when fed alone, but this increase did not change the shape of the dose-response curve or the estimated nutritional requirement. Large amounts of fish oil in the diet tended to depress the arachidonate concentration in tissue lipids. 相似文献
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Cells of Streptococcus faecalis incorporate radioactive glycerol exclusively into the glycerol moieties of monoglucosyl diglyceride, diglucosyl diglyceride, phosphatidyl diglucosyl diglyceride, phosphatidylglycerol, diphosphatidylglycerol, phosphatidic acid, diglyceride, and a phospholipid tentatively identified as an amino acyl phosphatidylglycerol. Phosphatidylglycerol is one of the major radioactive lipids synthesized and contains an equal amount of radioactivity in each of its two glycerol moieties. 相似文献
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ML Marin FJ Veith J Cynamon RE Parsons RT Lyon WD Suggs CW Bakal S Waahl LA Sanchez JG Yuan T Ohki 《Canadian Metallurgical Quarterly》1996,7(5):651-656
PURPOSE: The occurrence of neointimal hyperplasia within a stent may result in restenosis with recurrent symptoms of end-organ ischemia. This study evaluated the potential of a nonporous covering of a stent to function as a barrier to the formation of intrastent neointimal hyperplasia. MATERIALS AND METHODS: Twelve endovascular stent grafts were used to treat 12 high-risk patients with limb-threatening ischemia secondary to long-segment iliac artery occlusion. A 6-mm, thin-walled polytetrafluoroethylene graft was inserted and anchored to the common iliac artery with use of Palmaz stents. Each stent was covered by graft material over one-half of its length. Control angiograms obtained immediately after graft insertion were compared with follow-up angiograms obtained between 4 and 6 months after the initial procedure. On each angiogram, the region of the stent was magnified by 20x to permit computerized luminal diameter measurements. RESULTS: The mean luminal diameter within the stent was significantly greater on the covered (7.7 mm +/- 0.33 standard deviation) compared with the uncovered (6.7 mm +/- 0.85 standard deviation) portions (P < .01). CONCLUSIONS: Partially covered stents are a unique model for assessing the effects of an extrinsic stent covering on arterial healing and myointimal hyperplasia. These data suggest that a relatively nonporous covering of polytetrafluoroethylene may inhibit stent-related restenosis in iliac arteries. 相似文献
70.
WF Gee HL Holtgrewe PC Albertsen MS Litwin MJ Manyak MP O'Leary MR Painter RT Blizzard RB Fenninger L Emmons 《Canadian Metallurgical Quarterly》1996,156(5):1778-1780
PURPOSE: Trends of urologist practice patterns in evaluating and treating impotence, incontinence and infertility in the United States were assessed. MATERIALS AND METHODS: In July 1995 the executive interviewing branch of the Gallup Organization selected randomly and interviewed by telephone 533 practicing urologists in the United States who had provided urological patient care for more than 20 hours per week, practiced in 1994 and completed a urological residency program. RESULTS: Treatment of male sexual dysfunction and female urinary incontinence comprises a significant portion of the professional activity of United States urologists. However, evaluation and management of male infertility occupy a small portion of the average urological work load. While more than half of United States urologist office clinical laboratories were inspected in 1994, only 2% failed evaluation due to major deficiencies. CONCLUSIONS: Male sexual dysfunction and female urinary incontinence are major areas of urological practice in the United States but male infertility is not. Few United States urologist clinical laboratories failed inspection because of major deficiencies. 相似文献