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991.
AW Bradbury DJ Adam KR Makhdoomi WP Stuart JA Murie AM Jenkins CV Ruckley 《Canadian Metallurgical Quarterly》1998,85(5):645-647
BACKGROUND: This study reviews the results of infrarenal abdominal aortic aneurysm (AAA) surgery over 21 years (1 January 1976 to 31 December 1996). METHODS: A prospectively gathered database was analysed. RESULTS: Infrarenal AAA repair was performed in 1515 patients: 492 (32.5 per cent) had elective repair of an asymptomatic AAA; 194 (12.8 per cent) had elective repair of a symptomatic AAA; 156 (10.3 per cent) had emergency repair of a symptomatic non-ruptured AAA; and 673 (44.4 per cent) had surgery for a ruptured AAA. The 30-day and/or same admission mortality rates were 6.1, 5.8, 14.1 and 37 per cent respectively. Operative mortality increased in all four groups over the study interval, although this only attained statistical significance in patients having elective repair of a symptomatic, non-ruptured AAA. There was a significant increase in the age of patients undergoing elective repair of an asymptomatic AAA, but not in the other three groups. There was also a significant increase in the proportion of straight 'tube' grafts inserted in all four groups. CONCLUSIONS: It remains the minority of patients who have elective operation before the onset of symptoms and/or rupture. Despite anaesthetic and surgical specialization, the results of AAA repair have not improved over the past two decades. Operative mortality may be increasing, possibly because of the increasing age and associated comorbidity of the patients presenting to this unit. 相似文献
992.
KC Stange SJ Zyzanski TF Smith R Kelly DM Langa SA Flocke CR Jaén 《Canadian Metallurgical Quarterly》1998,36(6):851-867
OBJECTIVES: This study was designed to determine the optimal nonobservational method of measuring the delivery of outpatient medical services. METHODS: As part of a multimethod study of the content of primary care practice, research nurses directly observed consecutive patient visits to 138 practicing family physicians. Data on services delivered were collected using a direct observation checklist, medical record review, and patient exit questionnaires. For each medical service, the sensitivity, specificity, and Kappa statistic were calculated for medical record review and patient exit questionnaires compared with direct observation. Interrater reliability among eight research nurses was calculated using the Kappa statistic for a separate sample of videotaped visits and medical records. RESULTS: Visits by 4,454 patients were observed. Exit questionnaires were returned by 74% of patients. Research nurse interrater reliabilities were generally high. The specificity of both the medical record and the patient exit questionnaire was high for most services. The sensitivity of the medical record was low for measuring health habit counseling and moderate for physical examination, laboratory testing, and immunization. The patient exit questionnaire showed moderate to high sensitivity for health habit counseling and immunization and variable sensitivity for physical examination and laboratory services. CONCLUSIONS: The validity of the medical record and patient questionnaire for measuring delivery of different health services varied with the service. This report can be used to choose the optimal nonobservational method of measuring the delivery of specific ambulatory medical services for research and physician profiling and to interpret existing health services research studies using these common measures. 相似文献
993.
N Murugesan Z Gu PD Stein S Bisaha S Spergel R Girotra VG Lee J Lloyd RN Misra J Schmidt A Mathur L Stratton YF Kelly E Bird T Waldron EC Liu R Zhang H Lee R Serafino B Abboa-Offei P Mathers M Giancarli AA Seymour ML Webb JT Hunt 《Canadian Metallurgical Quarterly》1998,41(26):5198-5218
Substitution at the ortho position of N-(3,4-dimethyl-5-isoxazolyl) benzenesulfonamide led to the identification of the biphenylsulfonamides as a novel series of endothelin-A (ETA) selective antagonists. Appropriate substitutions on the pendant phenyl ring led to improved binding as well as functional activity. A hydrophobic group such as isobutyl or isopropoxyl was found to be optimal at the 4'-position. Introduction of an amino group at the 2'-position also led to improved analogues. Combination of the optimal 4'-isobutyl substituent with the 2'-amino function afforded an analogue (20, BMS-187308) with improved ETA binding affinity and functional activity. Compound 20 also has good oral activity in inhibiting the pressor effect caused by an ET-1 infusion in rats. Doses of 10 and 30 micromol/kg iv 20 attenuated the pressor responses due to the administration of exogenous ET-1 to conscious monkeys, indicating that the compound inhibits the in vivo activity of endothelin-1 in nonhuman primates. 相似文献
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AIMS OF THE STUDY: To determine the risk factors for local and distant failure in node-negative breast cancer treated with breast-conservative surgery and radiotherapy and to determine the relationship between these two events. MATERIAL AND METHODS: We retrospectively selected 908 patients who received conservative surgery and radiotherapy but no chemotherapy between 1980 and 1995, for a node-negative breast cancer. Patients were divided in two groups according to the status of the margins of resection. All pathology specimens were reviewed. RESULTS: In case of negative margins, the risk factors for local recurrences picked up by the Cox model were histologic multifocality (P = 0.0076), peritumoral vessel invasion (P = 0.021) and age < or = 40 years (P = 0.024), and in case of involved margins, negative oestrogen receptors (P = 0.0012), histologic multifocality (P = 0.0028), and absence of hormonal therapy (P = 0.017). The 10-year local recurrence rate was 18% in case of negative margins and 29% in case of involved margins, although in the latter case patients received high-dose adjuvant radiotherapy. Accordingly, the 10-year distant failure rates were 16% and 27%, respectively. Many arguments suggest that local and distant failures are closely related. CONCLUSION: Patients with histologic multifocality or positive margins are at high risk of local failure and then of distant failure, and require a more aggressive initial treatment. 相似文献
998.
JR Beach JH Dennis AJ Avery CL Bromly RJ Ward EH Walters SC Stenton DJ Hendrick 《Canadian Metallurgical Quarterly》1996,154(5):1394-1400
To clarify whether asthma may be caused by fume from welding mild steel and to evaluate the possible strength of such an effect, we quantified airway responsiveness among young shipyard workers with different levels of fume exposure. Clinical investigation comprised a cross-sectional survey of 19- to 27-yr-old workers who were completing 3 to 9 yr of employment in various trades, and a control group of 15- to 17-yr-old school leavers who were applying for apprenticeships within the same trades. Both groups were subdivided into negligible-, ambient-, or high-exposure subgroups according to expected levels of fume exposure. Actual exposures were assessed in a parallel environmental survey. Participants were investigated by questionnaire, skin prick tests, spirometry, and methacholine tests. Complete data sets were obtained from 1,024 of the 1,070 eligible subjects (96%). Among the workers but not the school leaver controls, there was an increasing prevalence of positive methacholine tests across the exposure subgroups-negligible 37%, ambient 44%, high 49% (p < 0.05). Regression analyses showed that in males after allowing for the effects of atopy, current smoking, and age, the estimated geometric mean level of airway responsiveness of regular welders was twice that of workers with negligible exposure after 5 yr of work. This implies that fume exposure may have been critical in causing asthma in about 1% of the welders. A lesser effect (though not significantly so) was noted among the workers with ambient exposure. 相似文献
999.
J Bj?rnsson RA McLeod KK Unni DM Ilstrup DJ Pritchard 《Canadian Metallurgical Quarterly》1998,83(10):2105-2119
BACKGROUND: Chondrosarcomas are common solid malignant tumors of bone, second in incidence only to osteosarcomas. The biologic evolution of chondrosarcomas is slow, requiring long follow-up intervals for meaningful survival analysis. METHODS: This study describes the clinicopathologic profiles of 344 patients, 194 male and 150 female (M:F, 1.3:1.0), with primary chondrosarcoma of long bones and limb girdles seen at 1 institution over a period of 80 years. RESULTS: The average age at presentation was 46 years (range, 5-82 years). The pelvis was the most common location (1.7% of all patients). Local pain was the most frequently reported initial symptom (81.4%). Survival analysis was limited to 233 patients whose primary treatment was given at the Mayo Clinic. All 233 patients had potential follow-up of at least 5 years. The overall 5-year survival rate was 77% (the expected rate was 96%). Local recurrence developed in 19.7% of patients and metastatic lesions in 13.7%. The recurrence rate was higher for tumors of the shoulder and pelvis than for tumors of long bones. Radiographically, chondrosarcomas had a characteristic appearance, including a combination of bone expansion and cortical thickening. Entering the tumor at surgery increased the risk of local recurrence. Histologic tumor grade was an important predictor of local recurrence and metastasis. CONCLUSIONS: With adequate initial surgical intervention, chondrosarcoma is primarily a local disease with a low metastatic rate. 相似文献
1000.
DJ Kwiatkowski DH Harpole J Godleski JE Herndon DB Shieh W Richards R Blanco HJ Xu GM Strauss DJ Sugarbaker 《Canadian Metallurgical Quarterly》1998,16(7):2468-2477
PURPOSE: To retrospectively construct a comprehensive multivariate model of cancer recurrence and to design a molecular pathologic substaging system in stage I non-small-cell lung cancer (NSCLC). METHODS: All patients with stage I NSCLC resected at Brigham and Women's Hospital (Boston, MA) between 1984 and 1992 with adequate clinical follow-up were studied. The importance of three demographic characteristics, surgical extent, 11 pathologic features, and seven molecular factors on cancer-free survival was examined. RESULTS: Two hundred forty-four patients were studied, with 25 noncancer deaths and 80 patients with recurrent disease. Significant univariate predictors (P < .05) of cancer recurrence were age older than 60 years, male sex, wedge resection, World Health Organization (WHO) adenocarcinoma subtype solid tumor with mucin, lymphatic invasion, and p53 expression. Multivariate analysis identified nine independent predictors of recurrence: solid tumor with mucin, a wedge resection, tumor diameter of 4 cm or greater, lymphatic invasion, age older than 60 years, male sex, p53 expression, K-ras codon 12 mutation, and absence of H-ras p21 expression. Multivariate cancer-free survival (CFS) analysis in the 180 patients who underwent lobectomy or pneumonectomy led to the elimination of sex and age, which left six independent factors. CONCLUSION: Lobectomy or pneumonectomy should be performed in stage I NSCLC. Using the six independent factors for recurrent disease, we propose a pathologic molecular substaging system. Patients with two factors or less are graded Ia, with a 5-year CFS rate of 87%; those with three factors are graded Ib, with a 5-year CFS rate of 58%; and those with four factors or more are graded Ic, with a 5-year CFS rate of 21%. 相似文献