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111.
Objectives Hereditary medullary thyroid carcinoma (MTC) is caused by germ‐line mutations in the RET proto‐oncogene. Our study addresses the difference in development of MTC between rare mutations in RET codons 790, 791 and 804. Design We evaluated tumour stage, calcitonin levels, biochemical cure rates and associated endocrinopathies in 153 German/Austrian patients with RET 790 (n = 47), 791 (n = 56) and 804 mutations (n = 50), divided into index‐ and screening groups. Results Age at diagnosis in index‐patients did not differ significantly among the three codon groups (medians of 57, 61 and 53 years). Tumour stage at diagnosis was significantly less advanced with codon 791 (n = 22) than 790 (n = 16) and 804 (n = 16) mutations (P = 0·001). In screening patients, age at diagnosis did not differ significantly among the three groups (medians 19, 24 and 32 years). Tumour stage at diagnosis was also significantly less advanced with codon 791 (n = 34) than 790 (n = 31) and 804 (n = 34) (P = 0·032). Preoperative basal calcitonin levels were significantly lower in codon 791 carriers compared to codon 790 carriers, and cure rates were significantly higher in both index (75%vs. 31%; P = 0·03) and screening patients (100%vs. 75%; P = 0·015). Additional endocrinopathies were observed only with codon 791 carriers (four pheochromocytomas and two hyperparathyroidism). Conclusion There is a significant difference in MTC development with less extensive C‐cell disease, higher cure rate and more frequent additional endocrinopathies in carriers of RET codon 791 mutations compared with carriers of codons 790 and 804 mutations. This information should be considered when age of prophylactic thyroidectomy is discussed.  相似文献   
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OBJECTIVE: Our objective was to compare four management strategies for heartburn: therapy with an H2-receptor antagonist (ranitidine), therapy with a proton pump inhibitor (lansoprazole), crossover from ranitidine to lansoprazole ("step-up" therapy), and crossover from lansoprazole to ranitidine ("step-down" therapy). METHODS: This was a controlled, double-blind, multicenter trial comprising 593 adults with heartburn, randomized to one of four groups for 20 wk. Subjects received either ranitidine 150 mg b.i.d. for 20 wk, or lansoprazole 30 mg once daily for 20 wk, or ranitidine 150 mg b.i.d. for 8 wk [corrected] followed by lansoprazole 30 mg once daily for 12 wk ("step-up"), or lansoprazole 30 mg once daily for 8 wk followed by ranitidine 150 mg b.i.d. for 12 wk ("step-down"). Outcome measures were based on self-reports in daily diaries of 24-h heartburn severity, measured by maximum daytime and nighttime severity, and percentage of 24-h heartburn-free days measured by absence of both daytime and nighttime heartburn. RESULTS: Median heartburn severity was significantly lower (p < 0.05) for lansoprazole (0.25) than the other groups (0.46 ranitidine, 0.44 "step-up," 0.35 "step-down"). The lansoprazole group had a significantly higher percentage of 24-h heartburn-free days (median 81.4%, p < 0.01) than other groups (66.6, 66.9, and 73.6%, respectively). In the "step-up" and "step-down" groups, heartburn was less severe, and percentages of 24-h heartburn-free days were higher during lansoprazole treatment regardless of treatment sequence. CONCLUSION: Proton pump inhibitor treatment provides more consistent heartburn relief than an H2-receptor antagonist, or "step-up" or "step-down" therapy.  相似文献   
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The mortality rate after acute myocardial infarction (AMI) has generally been modeled by a single exponential function. The present study was undertaken to determine, in 3 different populations, whether or not periods exist during the first year after AMI which have mortality distributions that differ from this pattern. The 3 patient populations included San Diego (346 patients, 71 deaths), Vancouver (704 patients, 146 deaths), and Copenhagen (1,140 patients, 262 deaths). Hospital admission was within 24 hours of the onset of symptoms, and patients dying within the first 24 hours after hospital admission or of noncardiac or unknown causes were not analyzed. The mortality between 2 and 21 days in the combined data base was 11.4% (range 10.9 to 11.7) and from 3 weeks to 1 year 10.5% (range 9.0 to 11.3). A high degree of similarity was noted among the shapes of the 3 survival curves. The hypothesis of an exponential mortality rate during the entire first year was rejected. Using a special statistic, changepoints at days 17,23, and 24 in the 3 populations (21 days for the combined data base) were identified and used thereafter to divide the year into 2 separate periods of mortality within which exponentiality for the mortality rate was not rejected. The point by which exactly 50% of deaths had occurred was day 19, with 75% of deaths occurring by day 100. These data further define the natural history after AMI and indicate optimal follow-up periods for short- and longer-term management strategies based on risk assessment or trials of risk reduction after AMI.  相似文献   
116.
Abstract. Comlekqi A, Biberoglu S, Kozan 0, Bahqeci 0, Ergene 0, Nazli C, Kinay 0, Guner G (Dokuz Eylul University, Medical School, Inciralti, Izmir, Turkey). Correlation between serum lipoprotein(a) and angio-graphic coronary artery disease in non-insulin-dependent diabetes mellitus. J Intern Med 1997; 242:449-54.
Objectives: To examine the impact of diabetic state on the concentrations of lipoprotein(a) [Lp(a)] in patients with non-insulin-dependent diabetes mellitus (NIDDM) and the correlation between angiographic coronary artery disease (CAD) and serum Lp(a) concentrations in NIDDM.
Design: In this cross-sectional study of 26 patients with NIDDM and 19 nondiabetic sex- and agematched patients who underwent coronary angiography, CAD was assessed visually using coronary artery score (CAS), and plasma Lp(a) was measured by an enzyme-linked immunosorbent assay.
Setting: The study was performed in an internal medicine clinic at a university hospital.
Subjects: Twenty-six age- and sex-matched patients with NIDDM and 19 control patients without diabetes.
Results: There was no significant difference between the Lp(a) concentrations of patientswith NIDDM and nondiabetic subjects (P > 0.05). When patients with NIDDM were stratified by absence or presence of CAD, patients with CAD had higher levels of Lp(a) (P < 0.05). However, there was no significant correlation between the concentrations of Lp(a) and CAS (P > 0.05).
Conclusions: Diabetic state does not have any impact on Lp(a) concentrations. Lp(a) excess seems to be atherogenic in patients with NIDDM as shown in nondiabetic patients in previous studies. Although diabetic patients with CAD have higher Lp(a) concentrations than the diabetic patients without CAD, Lp(a) levels were not correlated with CAS.  相似文献   
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BACKGROUND: Recent studies show that erythropoietin (EPO) plays a protective role in brain ischemia. In this condition, administration of EPO protects neurons from ischemic damage. Recently, it has been shown that in patients with chronic heart failure (CHF), EPO treatment improved cardiac function. In the present study we assessed the role of EPO and EPO-receptor (EPO-R) in the heart. METHODS AND RESULTS: We studied the presence and functionality of the EPO-R in isolated rat hearts in the Langendorff set-up. Hearts were perfused for 20 min with 10 U/ml EPO or vehicle. Immunohistochemistry revealed the presence of the EPO-R on endothelial cells, fibroblasts and to a lesser extent cardiomyocytes. Furthermore, perfusion with EPO resulted in a 50% increase in the phosphorylated MAP kinases p42/p44. To evaluate the protective role of EPO in cardiac ischemia, we performed low-flow (0.6 ml/min) ischemia/reperfusion experiments in isolated rat hearts. Administration of EPO (10 U/ml) reduced the cellular damage by 56% (P<0.05) during reperfusion, diminished apoptosis by 15% (P<0.05) and resulted in a significantly improved recovery of left ventricular pressure (P=0.02) and coronary flow (P=0.01). CONCLUSION: The present data suggest that a functional EPO-R is present in rat adult cardiac tissue and that exogenous EPO administration improves cardiac function after ischemia/reperfusion injury.  相似文献   
119.
The cure rate of acute uncomplicated urinary tract infection in general practice using 3 different treatment regimens, was studied in a randomized, multicenter trial. Patients were assigned to receive either cefadroxil 1 g once daily for 3 or 7 days or amoxycillin 375 mg t.i.d. for 7 days. 310 patients entered the study, of whom 230 could be evaluated according to the protocol. Two thirds of the cases were due to infections with Escherichia coli and about one fourth to Staphylococcus saprophyticus. No statistically significant differences in cure rates between the 3 regimens could be demonstrated neither at 1 week nor at 5 weeks of follow-up. The frequency of adverse reactions was low and similar in each treatment group.  相似文献   
120.
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