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101.
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AP McCormack H Niki P Kiser AF Tencer BJ Sangeorzan 《Canadian Metallurgical Quarterly》1998,19(7):452-461
The effect of two different methods of reconstruction of flatfoot deformity and the role of the posterior tibial tendon on the contact characteristics of the hindfoot joints were quantified using pressure-sensitive film. Each of 10 cadaver feet was loaded quasi-statically by an axial compressive force to simulate varying loads. First, a specimen was tested intact, then it was tested after sectioning the spring ligament and loading the specimen cyclically to create one type of flatfoot deformity. It was then tested again after reconstructing the deformity. Reconstructions used were the Dillwyn-Evans procedure (bone graft in osteotomy of the calcaneus) or the calcaneocuboid distraction arthrodesis (CCDA). We found that surgically produced flatfoot deformity altered mainly the talonavicular joint, by decreasing its contact area. The Dillwyn-Evans method had less effect on the talonavicular joint (altering 2 of 6 measured parameters) than the CCDA (3 of 6) and more effect on the anteriomedial facet (altering 3 of 6 parameters) than the CCDA (1 of 6). The Dillwyn-Evans method had more effect on the posterior facet (altering 2 of 6 measured parameters) than the CCDA (1 of 6). Function of the posterior tibial tendon had no effect on contact characteristics of the hindfoot joints after either type of reconstruction. These findings are based on measurements using a quasi-statically-loaded foot model at three selected positions, and results may be different with dynamic loading. 相似文献
104.
DJ Bjorkman DL Carr-Locke DR Lichtenstein AP Ferrari A Slivka J Van Dam DC Brooks 《Canadian Metallurgical Quarterly》1995,90(12):2128-2133
OBJECTIVES: Bile leaks are a well documented complication of biliary surgery, occurring more frequently with laparoscopic procedures. Endoscopic therapy with a long biliary endoprosthesis traversing the site of the leak is effective. We have evaluated the hypothesis that equalizing biliary and duodenal pressures with a short transpapillary stent is an equally effective therapy for bile leaks. METHODS: Thirty one consecutive patients presenting over a 52-month period with postsurgical bile leaks were evaluated. Patients had been treated with long endoprostheses (stents or nasobiliary tubes), sphincterotomy, or short transpapillary stents. The success, complication rate, need for additional therapy, and hospitalization time of each therapeutic approach were determined. RESULTS: Endoscopic therapy was successful in all 25 patients in whom a bile leak could be documented. The clinical success, need for radiological drainage, length of hospitalization, and incidence of pancreatitis were similar for all methods of treatment. CONCLUSIONS: These results confirm that endoscopic therapy is highly successful in the treatment of postoperative bile leaks and suggest that the mechanism of healing is the equalization of bile duct and duodenal pressures, allowing flow of bile into the duodenum. The endoscopic placement of short transpapillary stents without sphincterotomy is a temporary, effective, and technically simple method of pressure equalization. This should be considered as the primary therapy for most postoperative bile leaks. 相似文献
105.
LM Benson 《Canadian Metallurgical Quarterly》1998,18(5):92-93
Thirty-eight patients diagnosed as having continuous schizophrenia progrediens, 35 patients with shift-like schizophrenia and six patients with hypertoxic (feverish) schizophrenia were studied. The examinees displayed a marked increase in the blood content of lipid peroxidation products, such as malonic dialdehyde and conjugated dienes, together with an enhancement of the degree of erytrocytolysis, which events are particularly noticeable in hypertoxic- and continuous schizophrenia. Blood catalase activity gets higher, that of superoxide dismutase is on the decrease, which facts suggest to us some faults in the system of antioxidant defence. 相似文献
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TJ Christmas AP Doherty GJ Rustin MJ Seckl ES Newlands 《Canadian Metallurgical Quarterly》1997,84(7):1022-1025
BACKGROUND: Primary retroperitoneal germ cell tumours usually present as a large abdominal mass in young men. The testes are normal on examination and ultrasonography but there are usually raised serum levels of human chorionic gonadotrophin and/or alpha-fetoprotein. METHODS: Fourteen men (median age 33 years) with primary retroperitoneal germ cell tumours were treated by chemotherapy followed by surgical resection of the primary tumour and metastases via a thoracoabdominal extraperitoneal approach. RESULTS: There was minimal morbidity. The survival rate was 13 of 14 and the disease-free survival rate was 11 of 14 after a median follow-up of 15 months. CONCLUSION: The thoracoabdominal extraperitoneal approach for the removal of retroperitoneal germ cell tumours and their metastases after chemotherapy improves tumour clearance, morbidity and recovery time compared with the transperitoneal anterior approach. 相似文献
108.
Three variants of narcosis were compared in order to choose the optimal anesthesia for traumatic surgery involving blood loss of 15, 15 to 30, and more than 30% of the due volume of circulating blood. Microcirculation of the eye conjunctiva, central hemodynamics, hemostasis system, and lipid peroxidation were studied. Calypsol-based non-inhalation multicomponent intravenous anesthesia including neuroleptanalgesia and seduxen was found to be the least toxic and indicated for patients subjected to traumatic surgery involving blood loss of more than 30%. 相似文献
109.
Macrophages are considered to be the mediators of resistance to extra-intestinal Salmonella infections. Nevertheless, the initial cellular response to Salmonella infections consists primarily of polymorphonuclear leukocytes (PMN). To determine whether PMN serve an important function for the infected host, we made mice neutropenic with the rat mAb to RB6-8C5 and infected them i.v. with approximately 10(3) Salmonella dublin or an isogenic derivative that lacks the virulence plasmid (LD842). We infected BALB/c mice, which have a point mutation in the macrophage-expressed gene Nramp1 that makes them susceptible to Salmonella, and BALB/c.D2 congenic mice, which have the wild-type Nramp1 gene that makes them resistant to Salmonella. Both mouse strains were resistant to LD842, and neutropenia made only the BALB/c strain susceptible to this infection. Neutropenic congenic mice, however, were susceptible only to wild-type S. dublin (plasmid+). These results show a complex interplay between plasmid-virulence genes in Salmonella, host macrophages, and PMN. Mice with normal macrophages need PMN to defend against nontyphoid Salmonella that carry a virulence plasmid but not against Salmonella without virulence plasmids. Mice with a mutant Nramp1 gene need PMN to defend against all Salmonella, even those that lack virulence plasmids. These results, plus the evidence that PMN kill Salmonella efficiently in vitro, suggest that Salmonella have adapted to grow inside macrophages where they are relatively sheltered from PMN. The adaptations that allow Salmonella to survive in macrophages do not protect them from PMN. 相似文献
110.
Research findings regarding general self-concept, academic self-concept, and self-awareness in students with learning disabilities have varied, and results are still inconclusive regarding the consistency between students' and teachers' judgments of academic performance. The current study focuses on students' and teachers perceptions of the students' strategy use and performance in nine different academic and organizational domains. Six hundred sixty-three students and their 57 teachers were involved in the study. Findings indicated that the students with learning disabilities considered themselves appropriately strategic and competent in the five domains of reading, writing, spelling, math, and organization. These students also rated their academic performance and organization as average to above-average in seven of nine domains, with the exception of checking and planning their work. Nevertheless, the self-ratings of the students with learning disabilities were still significantly lower than the self-ratings of average achievers in virtually all domains. The second major set of findings revealed a sharp discrepancy between the self-assessments of the students with learning disabilities and their teachers' judgments. Teachers rated the students with learning disabilities as weak in their strategy use and below-average in their performance in all nine academic and organizational domains. Finally, gender differences were not evident in eight of the nine domains. These results have added to the increasing body of literature indicating that students with learning disabilities frequently perceive themselves as capable and effective and often rate themselves as academically stronger than their teachers judge them to be. 相似文献