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31.
Nine hundred and seventy eight patients admitted with a first myocardial infarction or episode of unstable angina were studied to determine for how long after they gave up smoking did the risk in ex-smokers continue to resemble those of current smokers. Logistic regression was used to calculate a score, based on a combination of age, cholesterol, and hypertension, that separated current smokers from lifetime non-smokers. When this function was applied to ex-smokers, only those who had given up at least 15 years before the attack had a risk factor profile similar to that of non-smokers. Those who had given up less than five years before the ischaemic attack had a significantly higher level of other risk factors than current smokers; those who had stopped for between five and 15 years had levels similar to those of current smokers. Ex-smokers are at higher risk of acute coronary disease for at least 15 years after stopping, but some immediate reduction in risk is possible.  相似文献   
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A 35 year old woman with multiple pulmonary arterial stenoses and occlusions was admitted with increasingly severe breathlessness. Balloon angioplasty of a life threatening stenosis in a remaining pulmonary artery branch was attempted on two occasions but without success. When a self-expanding stainless steel stent was inserted at the site of stenosis after a further angioplasty acute localised pulmonary oedema developed as blood flow distal to the lesion increased considerably. This was followed by a slow and dramatic improvement in the patient's condition. She no longer required an urgent transplant and resumed an active life.  相似文献   
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Two clusters of Serratia marcescens in 14 adult cardiac surgical patients occurred over 10 months in an 876-bed teaching hospital. The 14 infections that were studied were as follows: one sternal and five leg incisions, five pneumonias, one bacteremia, one urinary tract infection, and one infected internal defibrillator site. The first cluster included four pneumonias, one urinary tract infection, and one bacteremia. Corrective actions were taken based on outbreak data through no source was identified. No further infections occurred during the following 2 months. The second cluster included one sternal and five leg incisions, an infected internal defibrillator incision site, and one pneumonia. Serratia marcescens was isolated from six electrocardiogram rubber welsh bulbs with sensitivities identical to patient isolates that indicated a common source outbreak in at least the second cluster of infections. Disposable electrocardiogram leads were introduced and the problem was resolved. We conclude that reusable electrocardiogram welsh bulbs are a vector for postoperative infections.  相似文献   
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OBJECTIVE--To assess the long-term (four to 10 years) prognostic significance of transient ST segment changes on ambulatory ST segment monitoring after coronary artery bypass grafting (CABG). PATIENTS AND METHODS--76 patients (67 men, nine women) underwent CABG between 1982 and 1984 (n = 31) and between 1987 and 1988 (n = 45) and at a mean age of 57. All underwent 48 hours of ambulatory ST segment monitoring at a mean of 19 weeks after surgery. The results were available for assessment. All general practitioners were contacted and patients' notes reviewed. Patients were contacted by telephone. Details were recorded of intervening events (acute myocardial infarction, unstable angina, need for further revascularisation, and deaths). Event free survival curves were produced for those with and without transient ST segment changes during routine postoperative ambulatory ST segment monitoring. RESULTS--During 3213 hours of monitoring after CABG, 21 (27.6%) of 76 patients had transient ST segment changes, of which 70% were silent. Over a mean 70 month follow up period, patients with such ischaemic changes were no more likely to have either an objective (myocardial infarction or cardiac death) or subjective (unstable angina or another revascularisation) event than those patients without ischaemic changes. This finding was the same in patients operated on between 1987 and 1988 and between 1982 and 1984. CONCLUSIONS--Although ambulatory ST segment monitoring is becoming increasingly popular in some countries as a routine investigation for ischaemia in various coronary subgroups, the findings of such an investigation, when performed after CABG, do not help to identify a subgroup more likely to have an adverse outcome during up to 10 years of follow up. There seems to be no reason to perform this investigation after surgery, and particularly to refer patients for reinvestigation because of the detection of predominantly silent ST segment changes of uncertain relevance.  相似文献   
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Although most cancers are considered predominantly systemic processes, this may not hold true for hepatocellular carcinoma (HCC). The literature regarding patterns of progression of HCC (local versus systemic) has been relatively sparse. Our objectives were to: (1) analyze patterns of progression in HCC patients presenting with intrahepatic disease from initial treatment until death, and (2) identify clinically relevant risk factors for the development of metastases. Over a 9-year period, 285 patients treated with transarterial locoregional therapies underwent scheduled imaging follow-up from treatment until death and were categorized by pattern of progression: (i) intrahepatic (increased tumor enhancement/size, development/progression of vascular invasion, new hepatic lesions) progression or (ii) extrahepatic (adrenal/bone/lung/lymph node) metastases. Uni/multivariate analyses assessing the risk factors for the development of metastases were performed. The median time from last scan to death was 2.4 months (interquartile range: 1.3-4.8 months). The time to development of metastases, vascular invasion, and/or new lesions was 13.8 months (confidence interval: 11.3-17.7 months). Of the 209 patients followed until death, only 50 developed extrahepatic metastases (24%). Multivariate analyses identified age <65 years (P = 0.038), alpha-fetoprotein >200 ng/mL (P = 0.04), and vascular invasion (P = 0.017) as significant predictors of metastases development. CONCLUSION: Knowledge of the risk factors associated with the development of metastases may help guide assessment of patient prognosis. Because 76% of patients presenting with local disease treated with locoregional therapies die without developing extrahepatic metastases, the notion of HCC as a systemic disease, as detected by imaging, may be reconsidered.  相似文献   
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