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Macroamylasaemia was produced in vitro by incubation of hydroxyethylstarch with serum, and in vivo by intravenous infusion of hydroxyethylstarch. Gel filtration on Sephadex G-100 revealed distinct differences in molecular size distribution between such hydroxyethylstarch-induced macroamylase and the usual form of naturally occurring macroamylase which was observed in a few patients from our hospital. Further studies demonstrated that the gel filtration elution pattern of amylase activity in serum containing hydroxyethylstarch-induced macroamylase is significantly altered with time in vitro and in vivo, probably because of an enzymatic degradation of the hydroxyethylstarch components of the macromolecular complexes. In a healthy volunteer the serum amylase activity was elevated to a maximum of 797 u/l and the renal clearance rate of amylase was diminished to a minimum of 0.3 ml/min after infusion of 500 ml of a 6% solution of hydroxyethylstarch, as compared to 300 u/l, and 0.95 ml/min, respectively, during the pre-infusion period.  相似文献   
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We conducted an open observational study with blinded endpoint evaluation to validate the use of the Duke treadmill score in identifying patients likely to require coronary intervention. We studied 101 consecutive patients referred for coronary angiography from a cardiology clinic. All patients had a Bruce protocol exercise test. A 70% stenosis was regarded as significant. Patients were referred for percutaneous transluminal coronary angioplasty (PTCA) or coronary artery bypass grafting (CABG) surgery, if indicated. The Duke score was calculated as follows: exercise time (min) - (5 x ST segment deviation [mm]) - (4 x angina index [text]). Patients were classified into low, medium and high risk. The patients at high risk are more likely to have a significant stenosis (53/58 vs 30/43: p = 0.01 [OR 4.59 95% CI 1.34-16.6]) and require CABG or PTCA (47/58 vs 16/43: p < 0.001 [OR 7.21 95% CI 2.69-19.8]) than those at medium/low risk. Multiple logistic regression analysis, including ST segment depression, exercise time and symptoms shows that the score independently predicts a significant stenosis (p = 0.002) and the need for coronary intervention (p = 0.001). Introducing the score can help to identify those patients who need priority investigation.  相似文献   
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OBJECTIVE: To determine the effects of body temperature, ethanol use, electrolyte status, and acid-base status on the electrocardiograms (ECGs) of hypothermic patients. METHODS: Prospective, two-year, observational study of patients presenting to an urban ED with temperature < or =95 degrees F (< or =35 degrees C). All patients had at least one ECG obtained. Electrocardiograms were interpreted by a cardiologist blinded to the patient's temperature. J-point elevations known as Osborn waves were defined as present if they were at least 1 mm in height in two consecutive complexes. RESULTS: 100 ECGs were obtained in 43 patients. Presenting temperatures ranged between 74 degrees F and 95 degrees F (23.3 degrees C-35 degrees C). Initial rhythms included normal sinus (n = 34), atrial fibrillation (n = 8), and junctional (n = 1). Osborn waves were present in 37 of 43 initial ECGs. Of the six initial ECGs that did not have Osborn waves present, all were obtained in patients whose temperatures were > or =90 degrees F > or =32.2 degrees C). For the entire group, the Osborn wave was significantly larger as temperature decreased (p = 0.0001, r = -0.441). The correlation between temperature and size of the Osborn wave was strongest in six patients with four or more ECGs (range r = -0.644 to r = -0.956, p = 0.001). No correlation could be demonstrated between the height of the Osborn waves and the serum electrolytes, including sodium, chloride, potassium, bicarbonate, BUN, creatinine, glucose, anion gap, and blood ethanol levels. CONCLUSIONS: The presence and size of the Osborn waves in hypothermic patients appear to be a function of temperature. The magnitude of the Osborn waves is inversely correlated with the temperature.  相似文献   
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PURPOSE OF REVIEW: Interstitial lung disease frequently complicates the rheumatic diseases. The purpose of this review is to outline recent advances and current concepts regarding the management of these interstitial lung diseases. RECENT FINDINGS: Several histologic lesions cause interstitial lung disease in rheumatic diseases, including nonspecific interstitial pneumonia, usual interstitial pneumonia, organizing pneumonia, lymphocytic interstitial pneumonia, desquamative interstitial pneumonia, and acute interstitial pneumonia. Although the relative frequency of occurrence of these histopathologic lesions is not definitively established, it seems that nonspecific interstitial pneumonia accounts for a large proportion of rheumatic disease-associated interstitial lung diseases. Although usual interstitial pneumonia generally responds poorly to corticosteroid therapy, other forms of interstitial pneumonia are often steroid responsive and have a more favorable long-term prognosis. Pulmonary hypertension is increasingly recognized as a complication of these interstitial lung diseases. Treatment of pulmonary hypertension in these patients provides clinical benefit and may suppress pulmonary inflammation and fibrosis. Lung transplantation is a treatment option for selected patients with severe pulmonary involvement and limited life expectancy. SUMMARY: Interstitial lung disease is common in the rheumatic diseases, may be caused by a variety of lesions that respond differently to treatment, and may lead to the development of pulmonary hypertension. Whether the prognosis of interstitial lung disease associated with rheumatic disease is similar to that associated with the idiopathic interstitial pneumonias is not known. Treatment of these interstitial lung diseases should take into account the specific histologic lesion, the activity of the underlying rheumatic disease, and associated pulmonary hypertension, if present. The diagnosis of a rheumatic disease is no longer an absolute contraindication to lung transplantation.  相似文献   
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