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981.
The steady-state pharmacokinetics of an ultralong sustained release formulation of theophylline (Unilong) twice daily (bid) in elderly hospitalized patients suffering from chronic obstructive pulmonary disease (COPD) have been studied in order to establish guidelines for monitoring. The study was carried out in 37 patients (33 men), aged 60-87 years. Samples were collected from 0 to 12 h after the morning dose on day 9 of treatment with 250 mg bid (n=25) or 375 mg bid (n=12). Considerable variability in apparent clearance (range 0.33-1.49 ml/min per kg of ideal body weight), Css(min)/D (range 0.28-1.86), Css(max)/D (range 0.65-2.33) and (Css(max)-Css(min))/Css(avg) (range 0.18-0.80) was observed. There was no significant correlation between the patient's age and apparent clearance within this elderly population. The concentration-to-dose ratio and the relationship between the steady-state plasma concentration at different times during the dosage interval and Css(avg) are described. It is concluded that the interpatient variability in peak-trough fluctuation of this formulation was higher than that described in healthy volunteers by other investigators, and that the apparent clearance did not decrease with age within this elderly population with COPD. The importance of theophylline monitoring is emphasized and rules to estimate Css(avg) and Css(5h) from Css(0h) when only a single sample obtained before the morning dose is available are given.  相似文献   
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983.
Interviews with senior managers and clinicians involved in the national booking programme and cancer care collaborative found that scepticism, particularly among doctors, was a barrier to implementing change. Regular feedback and clear evidence of change emerged as key factors in persuading sceptics of the benefits of different ways of working. Getting sceptics on board can be a long process and time spent talking to them is not wasted. Consultants' support is key for endorsing change.  相似文献   
984.
The American Society of Transplant Surgeons and the American Society of Transplantation jointly sponsored their third American Transplant Congress on May 30-June 4, 2003. The meeting, which took place in Washington, D.C., U.S.A., thoroughly reviewed the different immunosuppressive protocols for every kind of transplantation. Also presented were the immunological and nonimmunological factors influencing the success or failure of transplants from the point of view of genetics, the place of new investigative agents and the current status of various therapeutic protocols intended to induce tolerance or normal function of grafts in the absence of immunosuppressive treatment. Presentations on renal, liver, heart, lung, multivisceral and islet transplantation are covered in this report, as well as aspects of new immunosuppressive agents, genomics in transplantation and tolerance induction in allotransplantation.  相似文献   
985.
Surgical outcome in 85 patients with primary cardiac tumors   总被引:7,自引:0,他引:7  
BACKGROUND: We present a large, single institution experience with adult cardiac tumors and address factors affecting outcome. METHODS: A retrospective review was made of all patients who underwent surgery for primary cardiac tumors from April 1975 through August 2002. RESULTS: Eighty-five patients (33 male and 52 female) with a mean age of 54 years were identified with follow-up available for 80 (94%) patients. There were 68 (80%) benign tumors and 17 (20%) malignant tumors. Three tumors recurred and were resected giving a total of 88 surgeries. All benign tumors were grossly resected and the extent of resection for malignant disease ranged from 14 (78%) gross resections and 3 (17%) debulkings to 1 (5%) biopsy. There were 4 (5%) early hospital deaths. Median survival was 9.6 months and 322 months for patients with malignant and benign diseases, respectively. Significant predictors of long-term mortality were malignant disease (P <0.0001) and New York Heart Association class (P <0.03). CONCLUSIONS: Surgical resection provides excellent outcome in patients with benign cardiac tumors. Malignant tumors continue to pose a challenge with good local tumor control but limited survival owing to metastatic disease.  相似文献   
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990.
Cancer incidence among 10,211 airline pilots: a Nordic study   总被引:5,自引:0,他引:5  
BACKGROUND: Commercial airline pilots are exposed to cosmic radiation and other potentially carcinogenic elements during work and leisure activities. HYPOTHESIS: Work-related factors affect cancer pattern of the pilots. METHODS: A cohort of 10,051 male and 160 female airline pilots from Denmark, Finland, Iceland, Norway, and Sweden was followed for cancer incidence through the national cancer registries. There were 177,000 person-years at follow-up, 51,000 of them accumulated after 20 yr since the time of first employment. Standardized incidence ratios (SIRs) were defined as ratios of observed over expected numbers of cases based on national cancer incidence rates. Dose-response analyses were done with Poisson regression method. RESULTS: Among male pilots, there were 466 cases of cancer diagnosed vs. 456 expected. The only significantly increased SIRs concerned skin cancer: melanoma 2.3 (95% CI 1.7-3.0), squamous cell cancer 2.1 (1.7-2.8), and basal cell carcinoma 2.5 (1.9-3.2). The relative risk of skin cancers increased with the time since first employment, the number of flight hours, and the estimated radiation dose. There was an increase in the relative risk of prostate cancer with increasing number of flight hours in long-distance aircraft (p trend 0.01). No increased incidence was found for acute myeloid leukemia or brain cancer which were of interest a priori based on earlier studies. CONCLUSIONS: This large study, based on reliable cancer incidence data, showed an increased incidence of skin cancer. It did not indicate a marked increase in cancer risk attributable to cosmic radiation although some influence of cosmic radiation on skin cancer cannot be entirely excluded.  相似文献   
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