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161.
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The degradation and excretion of 2-14C-uric acid were examined in three adult woolly monkeys (Lagothrix lagothrichia) to determine the basis for the relatively high serum and urinary uric acid concentrations previously reported in this species. Like man and the great apes which lack uricase, but in distinction to most other mammals, these animals converted very little urate to allantoin. Uric acid turnover, as has been reported for other New World monkeys, was several times that of normal man. Renal urate excretion as well as disposition by extrarenal mechanisms may protect Lagothrix vrom hyperuricemia. The capacity to convert urate to allantoin appears to have been lost late in the evolution of New World monkeys. The woolly monkey deserves further study as a primate model for investigations of enzyme replacement strategies. 相似文献
163.
The outdating of units of blood can be reduced by decreasing the amount of time they spend in an assigned or crossmatched status. This reduction can be achieved in a hospital by establishing a maximum surgical blood order schedule (MSBOS) which reduces the excessive number of units of blood crossmatched preoperatively for patients undergoing elective surgery. The various steps which occurred in the development of a MSBOS in a large general hospital are detailed and the projected reduction in the number of crossmatched units which can be achieved with the MSBOS is illustrated. illustrated. The projected number of units of blood transfused to patients during their hospitalization for 50 common primary surgical procedures in the United States during 1974 is presented as a basis for defining maximum blood orders for each procedure. 相似文献
164.
We have modified a snare technique originally described for transcolonoscopic removal of colonic polyps for the retrieval of intravascular foreign bodies. The key difference from other snare techniques is the employment of a wire snare with a crimp in its midportion that enables the formation of a loop in a plane perpendicular to the axial direction of the guiding catheter. With this technique we have quickly removed a variety of objects from the right heart and pulmonary arteries in four patients. 相似文献
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CA Engh JP Hooten KF Zettl-Schaffer M Ghaffarpour TF McGovern GE Macalino BA Zicat 《Canadian Metallurgical Quarterly》1994,(298):89-96
Fifteen years of clinical experience with porous-coated prostheses demonstrated the durability of this type of fixation. This experience was documented by clinical follow-up study of the 393 cases treated by the senior author before 1985. Only six of these femoral components have been revised: three for loosening, two for stem breakage, and one for infection. Thus, the revision rate for the porous-coated stems was 1.5%. Porous-coated acetabular components were used in 227 of the arthroplasties. Five of these porous-coated cups have been revised: four for malposition leading to dislocation and one for late loosening secondary to osteolysis. Thus, the revision rate for these porous-coated acetabular components was 2.2%. Twenty bipolar and 146 cemented acetabular components were used in the remaining 166 cases treated before 1985. Eleven (7.5%) of the cemented acetabular components were revised. Revisions of the porous-coated components were rare in the first ten postoperative years. The clinical data were supplemented with analysis of postmortem specimens from 15 patients. Mechanical testing of the femoral specimens showed the relative micromotion at the porous surface to be exceptionally small (less than 40 microns). Seven of these postmortem retrievals involved cases with unilateral arthroplasties. In these cases, the contralateral normal femur also was removed, and a prosthesis identical to that in the in vivo implanted side was inserted to simulate the immediate postoperative condition. Dual-energy X-ray absorptiometry (DEXA) of the seven paired femora demonstrated that bone remodeling can be expected to produce a 5%-52% loss of periprosthetic bone mineral content, with the greatest loss occurring in the more osteoporotic patients.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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壳聚糖、竹粉和PVC等按一定比例混合,用挤出成型法制备了竹粉/PVC复合材料。考察了壳聚糖添加量对复合材料物理力学性能、热稳定性、防水性能和防腐性能的影响。结果表明,适量壳聚糖的添加,可以改善复合材料的综合性能。且当壳聚糖含量为3wt%时复合材料的性能最佳,与未添加壳聚糖的复合材料相比,其拉伸强度、冲击强度和弯曲强度分别提高了44.7%、58.2%和79.6%,腐蚀前8天的吸水率从2.2%降低为1.6%,被白腐菌和褐腐菌腐蚀后材料的质量损失率分别降低了94.1%和75.0%。 相似文献
170.
为了满足在区域尺度上大气气溶胶垂直分布的探测需求,在中国科学院重大科技基础设施项目“航空遥感系统”的资助下,研制了机载双波长偏振激光雷达。本文介绍了该机载激光雷达的主要功能和性能参数,以及在华北地区开展的飞行观测实验,取得的结果表明,该机载激光雷达性能稳定,其探测精度达到设计要求,可以为污染源的识别和传输路径的探测提供高时空分辨率的数据,为认知大气气溶胶的微物理特性和分类提供了重要的机载遥感平台。 相似文献