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991.
C Schiller R Windhager EJ Fellinger M Salzer-Kuntschik A Kaider R Kotz 《Canadian Metallurgical Quarterly》1995,77(4):608-614
From 1986 to 1991 we fitted 20 children with endoprostheses after resection of malignant bone tumours of the leg; six have reached skeletal maturity and are the subject of this study. Reconstruction of defects in growing limbs in which the eventual shortening can be predicted requires the use of extendable prostheses. The mean age at operation was 11 years (9.2 to 13.7) and the average follow-up period was 6.3 years (4.3 to 7.6). The diagnosis was osteosarcoma in five patients and Ewing's sarcoma in one. All tumours were Enneking stage-IIB. When seen for follow-up all patients were free from disease. The extendable implants used included the Pafford-Lewis prosthesis and the Kotz Modular Femur Tibia Reconstruction system with a compatible, newly-designed growth module. Telescope-like elongation of the prostheses was performed by insertion of a screwdriver through a small skin incision. Active epiphyseal growth in the adjacent growth plate was preserved by using prosthetic stems with a smooth surface. The mean length gained was 13.15 cm (4.5 to 19.5) requiring 53 planned procedures. Seven revision operations were necessary for complications. Functional evaluation showed excellent and good results in all cases. Stress-shielding at the site of anchorage of the prosthesis was more pronounced than in adults. Implantation of extendable endoprostheses in children provides a reasonable alternative to rotationplasty, but limb salvage requires more operations. 相似文献
992.
K Bhol A Mohimen R Neumann J Yunis S Foster EJ Yunis AR Ahmed 《Canadian Metallurgical Quarterly》1996,15(5):521-532
Dupuytren's contracture (DC) is a disease of the palmar fascia resulting in thickening and contracture of fibrous bands on the palmar surface of the hands and fingers. For decades, a controversy has existed regarding whether acute traumatic injury or cumulative biomechanical work exposure can contribute to the development of this disorder. To address this controversy, this review considers the following questions: Is there evidence that DC is associated with 1) frequent or repetitive manual work; and 2) hand vibration? The published literature was searched for studies meeting the following criteria: 1) in English or having an English abstract; 2) controlled studies; 3) DC an identified health outcome studied; and 4) the study group exposed to repetitive or frequent manual work, vibration, or acute traumatic injury. Relevant non-English articles identified through English abstracts were translated. The validity of studies meeting the selection criteria was assessed using a series of questions adapted from those of Stock [1991: Am J Ind Med 19:87-107]. Studies that met a priori minimum levels of methodologic quality were taken into account to reach conclusions with respect to the above questions. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for each study. Ten studies met the initial selection criteria. Of these, four studies met the criteria for methodologic quality, one addressing the relationship between manual work and DC, and three studies of vibration and DC. No controlled studies of acute trauma and DC were identified. Bennett [1982: Br J Ind Med 39:98-100] found the prevalence of DC at a British PVC bagging and packing plant in which workers were exposed to repetitive manual work to be 5.5 times that at a local plant without packing, and twice the expected prevalence in a U.K. working population previously studied by Early [1962: J Bone Joint Surg 44B:602-613]. DC was observed more frequently among vibration white finger claimants than controls by Thomas and Clarke [1992: J Soc Occup Med 42:155-158] (OR, 2.1; 95% CI, 1.1-3-9), and more frequently among vibration-exposed workers than controls by Bovenzi et al. [1994: Occup Environ Med 51:603-611] (OR, 2.6 95% CI, 1.2-5.5). Cocco et al [1987: Med Lav 78:386-392] found that a history of vibration exposure occurred more frequently among cases of DC than among controls (OR, 2.3; 95% CI, 1.5-4.4). The latter two studies presented some evidence of a dose-response relationship. There is good support for an association between vibration exposure and DC. 相似文献
993.
Two patients suffering from pelveoperitonitis had ascites and elevated CA 12-5 serum level mimicking epithelial ovarian cancer. Both were treated successfully with antibiotics, after laparoscopic confirmation. 相似文献
994.
S Kapiotis G Sengoelge WR Sperr M Baghestanian P Quehenberger D Bevec SR Li EJ Menzel A Mühl D Zapolska I Virgolini P Valent W Speiser 《Canadian Metallurgical Quarterly》1996,58(23):2167-2181
Leukocyte adhesion and transmigration through the endothelial cell (EC) layer plays a crucial role in inflammation. IL-1 alpha and TNF alpha increase EC-adhesiveness for leukocytes by stimulating surface expression of ICAM-1 (intercellular adhesion molecule 1, CD54), VCAM-1 (vascular cell adhesion molecule 1, CD106) and E-selectin (CD62E). In this study, the effects of ibuprofen on IL-1 alpha and TNF alpha-induced expression of ICAM-1, VCAM-1 and E-selectin on cultured human umbilical vein EC (HUVEC) were analyzed. Exposure to IL-1 alpha or TNF alpha resulted in an increased expression of VCAM-1, ICAM-1, and E-selectin. Ibuprofen was identified as a potent inhibitor of IL-1 alpha and TNF alpha-induced surface expression of VCAM-1 and a less potent inhibitor of pyrogen-induced expression of ICAM-1, whereas no effect on E-selectin was found. The effects of ibuprofen on VCAM-1 expression were dose-dependent (IC50 [IL-1 alpha]: 0.5 mM; IC50 [TNF alpha]: 0.5 mM) and time-dependent with maximum responses observed after 18 h. Moreover, ibuprofen abrogated pyrogen-dependent adhesion of leukocytes to HUVEC. Ibuprofen also inhibited VCAM-1 mRNA expression in pyrogen activated EC. VCAM-1-downregulation on EC by ibuprofen may contribute to the anti-inflammatory actions of the drug. 相似文献
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999.
Louis J. Everett 《野外机器人技术杂志》1989,6(1):19-33
Single point sensors can measure the position of one point fixed to a manipulator's end effector. When single point sensors have been used for calibration, it has not been possible to calibrate the orientation of the tool. Furthermore, it can be difficult to calibrate the sensor system. Results in the literature seldom provide a complete kinematic calibration of the manipulator. Presented here is a technique that enables single point sensors to gather sufficient information to complete kinematic calibration. In addition, the method can reduce the burden of calibrating the sensor system. 相似文献
1000.
EJ Flannery 《Canadian Metallurgical Quarterly》1995,23(1):7-12; discussion 13-4