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171.
172.
AP Mitterhofer M Antonelli I Genuini G Bertazzoni 《Canadian Metallurgical Quarterly》1998,17(2):213-215
Experimental and clinical studies have recently shown variable degrees of structural abnormalities in the transposed and chronically stimulated muscle graft after cardiomyoplasty procedure. The postoperative stimulation protocol of wrapped skeletal muscle has been claimed to be a major determinant of late structural derangement. Therefore, a modified stimulation protocol had been used after a cardiomyoplasty procedure in a 63-year-old patient. Improved postoperative hemodynamic data could be detected by pressure/volume analysis. After unexpected sudden death occurred at 15 months, autoptic examination showed preserved muscle structure, suggesting that a prudent stimulation protocol may maintain muscle viability and contribute to effective cardiac support. 相似文献
173.
174.
AP Lake 《Canadian Metallurgical Quarterly》1998,80(5):698-699
We report a case of a flexor sheath tenosynovitis caused by Mycobacterium marinum. 相似文献
175.
In the common carotid artery, reflections originating from the periphery and the flow divider may affect the shape of the flow velocity profile and, hence, near-wall shear rate (WSR) differently just before the bifurcation (location B) than 20 to 30 mm farther upstream (location A). Recent developments in ultrasound technology allow the assessment of WSR and intima-media thickness (IMT) at the same site in the carotid artery in vivo. We therefore determined WSR at locations A and B and investigated whether the differences between both sites, if any, were associated with different IMTs and different mechanical properties of the arterial wall. The effect of age on the possible differences was assessed as well. The study was performed on presumably healthy volunteers (n=53). In all individuals, IMT was larger at location B than at location A. The relative difference in IMT between both locations was not affected by age. No significant differences in diameter and distension were found between locations. Near peak systolic and near mean WSR at the posterior wall (PWSRp and MWSRp, respectively) were significantly lower at location B than at location A. The relative differences in PWSRp and MWSRp between both locations within subjects were independent of age. The velocity profiles were more blunted at location A than at location B. PWSRp and MWSRp significantly decreased and IMT significantly increased with age at both locations. IMT was negatively correlated with PWSRP and MWSRP at location B, but this correlation was not significant at location A. In summary, in the common carotid artery, the lower WSR near the bifurcation, as compared with 20 to 30 mm upstream, is associated with a larger IMT than at the more proximal site. The relative difference between both locations within subjects is independent of age. 相似文献
176.
ZI Kravchuk AA Chumanevich AP Vlasov SP Martsev 《Canadian Metallurgical Quarterly》1998,217(1-2):131-141
Injection of anti-AChR antibodies in passive transfer experimental autoimmune myasthenia gravis (EAMG) results in increased degradation of acetylcholine receptor (AChR) and increased synthesis of AChR alpha-subunit mRNA. Passive transfer of anti-Main Immunogenic Region (MIR) mAb 35 in aged rats does not induce clinical signs of disease nor AChR loss. The expression of the AChR subunit genes was analyzed in susceptible and resistant rats. In aged EAMG resistant rats, no increase in the amount of AChR alpha-subunit mRNA was measured. In vivo AChR degradation experiments did not show any increase in AChR degradation rates in aged resistant rats, in contrast to young susceptible rats. Taken together, these data demonstrate that resistance of the AChR protein to antibody-mediated degradation is the primary mechanism that accounts for the resistance to passive transfer EAMG in aged rats. 相似文献
177.
AP Mirra FA Justo JE Miziara CA Schneider N Trippe 《Canadian Metallurgical Quarterly》1995,41(4):277-283
OBJECTIVES: From 1947-1986 we reviewed a historical series of 1,900 cases of esophageal cancers registered at the A.C. Camargo Hospital, S?o Paulo, Brazil. Two hundred and thirty four cases were submitted to surgical resection. During these 4 decades the treatment philosophy of these tumors has changed. METHOD: Five different historical groups were identified and the results are presented. RESULTS: The first group (1947-60) consisted of 47 cases only submitted to surgical resection. The second group (1961-70) of 56 cases had pre and pos surgery radiotherapy in low doses and the reconstruction was made using subcutaneous colon. From 1971-75 the same approach was used except with high dose preoperative radiotherapy (31 cases). In the 4th group (1976-82) of 68 cases preoperative radiotherapy (high dose) and chemotherapy were used. In the last group (1983-86) composed of 32 cases the treatment was preoperative chemotherapy, surgical resection with gastric reconstruction followed with high doses radiotherapy in the surgical bed and chemotherapy. The only significant prognostic factors in the statistical analysis were tumor size and involvement peri-esophageal lymph nodes. CONCLUSION: A five year survival from 3.7% to 9.0% was obtained through the use of the fifth group treatment planning. 相似文献
178.
SJ Hedley DJ Gawkrodger AP Weetman R Morandini JM Boeynaems G Ghanem SM Neil 《Canadian Metallurgical Quarterly》1998,138(3):536-543
alpha-Melanocyte stimulating hormone (alpha-MSH) was found significantly to reduce tumour necrosis factor-alpha (TNF-alpha) stimulated upregulation of intercellular adhesion molecule-1 (ICAM-1) in normal adult cutaneous melanocytes. The maximum inhibitory response to alpha-MSH was obtained at around 10(-10) mol/L alpha-MSH when cells were coincubated with alpha-MSH and TNF-alpha for 24 h. alpha-MSH had little or no effect on basal ICAM-1 expression in melanocytes and the effects of alpha-MSH could be mimicked with 3-isobutyl-1-methylxanthine (IBMX). Preliminary data in three human melanoma cell lines also showed alpha-MSH and forskolin to be effective in significantly reducing TNF-alpha stimulated ICAM-1 expression over 24 h. The extent of the inhibition varied from cell line to cell line and was greatest in those cells with the highest number of alpha-MSH receptors. These data suggest that alpha-MSH has the ability to oppose the action of the pro-inflammatory cytokine TNF-alpha on melanocytes and melanoma cells. 相似文献
179.
AP Sandhu RP Symonds AG Robertson NS Reed SG McNee J Paul 《Canadian Metallurgical Quarterly》1998,40(3):575-581
BACKGROUND: The Quebec Neuroblastoma Screening (QNS) Project completed a 5-year program for measuring urinary vanillylmandelic acid (VMA)/homovanillic acid (HVA) levels at age 3 weeks and/or 6 months in 89% of 476,603 Quebec-born infants from 1989-1994; 45 screening positive preclinical cases (S-positive cases) and 20 congenital/neonatal (C/N) cases were identified. As of April 1997, an additional 59 cases in the same birth cohort were diagnosed clinically; these neuroblastomas developed after screening verified normal VMA/HVA levels (S-negative cases). METHODS: Pathology specimens from 45 of 59 S-negative cases were reviewed centrally and classified according to the Shimada system. Results were compared with clinical data and also with S-positive and C/N cases. RESULTS: Of 45 S-negative cases, 27 tumors had favorable histology (FH) and 18 had unfavorable histology (UH). Approximately 52% of FH tumors were diagnosed before age 1 year, whereas UH tumors were nearly exclusively (94%) diagnosed after age 1 year (P < 0.01). Approximately 89% of FH tumors were Stage I, II, or IV-S, whereas 72% UH tumors were Stage III or IV (P < 0.001). All children with FH tumors were alive at last follow-up (range of follow-up period: 9-79 months; median, 35 months), whereas 8 children with UH tumors died of disease even after limited follow-up (range of follow-up period: 0-60 months; median, 20 months). By contrast, S-positive and C/N cases were predominantly (97%) FH tumors, often (76%) Stage I, II, or IV-S, with excellent clinical outcome (survival rate of 98%). CONCLUSIONS: The majority of the UH neuroblastomas that developed in the birth cohort of the QNS Project were included in the group of S-negative cases and could not be detected by the screening at age 3 weeks and/or 6 months. 相似文献
180.
EA Zias C Mavroudis CL Backer LM Kohr NL Gotteiner AP Rocchini 《Canadian Metallurgical Quarterly》1998,66(5):1551-1559
BACKGROUND: Mitral valve remodeling techniques were applied to 26 infants and children (mean age, 6.0 years, range, 0.4 to 15.9 years) with various forms of congenital mitral valve disease over a 7-year period. Patients with atrioventricular canal, L-transposition and single ventricle were excluded. Intraoperative transesophageal echocardiography (TEE) was utilized to assess the repair and guide the need for immediate intervention. METHODS: Twenty-one patients had mitral regurgitation: 10 with cleft anterior mitral leaflet, 7 with annular dilatation, 1 with normal leaflets with an obstructing cord, 2 with prolapsed leaflets and elongated cords, and 1 with restricted leaflet motion, normal papillary muscles, and shortened cords. Of the 5 mitral stenosis patients, 3 had supravalvular mitral ring, 1 had midvalvular mitral ring, and 1 had a parachute valve. Three of the mitral stenosis patients had additional stenotic lesions. Concurrent repair of associated lesions was performed in 21 patients (78%). RESULTS: Operative mortality was 3.8% (n = 1). There were no late deaths. Immediate rerepair in 4 patients resulted in improved function. All mitral stenosis patients improved. A total of 20 mitral regurgitation patients (95%) improved; 1 required mitral valve replacement. Mean follow-up is 31 months (range, 2 to 81 months). All patients are in New York Heart Association functional class I or II. CONCLUSIONS: Mitral valve repair can be successfully performed in infants and children with excellent short- and midterm results. Assessment using transesophageal echocardiography can guide the necessity for immediate rerepair to achieve improved function. 相似文献