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71.
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   
72.
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   
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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   
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Diabetic polyneuropathy (DPN) can be classified based on fiber diameter into three subtypes: small fiber neuropathy (SFN), large fiber neuropathy (LFN), and mixed fiber neuropathy (MFN). We examined the effect of different diagnostic models on the frequency of polyneuropathy subtypes in type 2 diabetes patients with DPN. This study was based on patients from the Danish Center for Strategic Research in Type 2 Diabetes cohort. We defined DPN as probable or definite DPN according to the Toronto Consensus Criteria. DPN was then subtyped according to four distinct diagnostic models. A total of 277 diabetes patients (214 with DPN and 63 with no DPN) were included in the study. We found a considerable variation in polyneuropathy subtypes by applying different diagnostic models independent of the degree of certainty of DPN diagnosis. For probable and definite DPN, the frequency of subtypes across diagnostic models varied from: 1.4% to 13.1% for SFN, 9.3% to 21.5% for LFN, 51.4% to 83.2% for MFN, and 0.5% to 14.5% for non‐classifiable neuropathy (NCN). For the definite DPN group, the frequency of subtypes varied from: 1.6% to 13.5% for SFN, 5.6% to 20.6% for LFN, 61.9% to 89.7% for MFN, and 0.0% to 6.3% for NCN. The frequency of polyneuropathy subtypes depends on the type and number of criteria applied in a diagnostic model. Future consensus criteria should clearly define sensory functions to be tested, methods of testing, and how findings should be interpreted for both clinical practice and research purpose.  相似文献   
79.
Clinical Oral Investigations - This study evaluated the reproducibility of electronic color determination system evaluations of the marginal gingiva, which could be important for adhesive cervical...  相似文献   
80.
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a hereditary cardiac condition associated with ventricular arrhythmias, heart failure, and sudden death. The most frequent ARVC genes encode desmosomal proteins of which mutations in desmoglein‐2 (DSG2), account for 10%–20% of cases. This study aimed to investigate how DSG2 mutations contribute to the pathogenesis of ARVC. Initial mutation analysis of DSG2 in 71 probands identified the first family reported with recessively inherited ARVC due to a missense mutation. In addition, three recognized DSG2 mutations were identified in 12 families. These results and further mutation analyses of four additional desmosomal genes indicated that ARVC caused by DSG2 mutations is often transmitted by recessive or digenic inheritance. Because desmosomal proteins are also expressed in skin tissue, keratinocytes served as a cell model to investigate DSG2 protein expression by Western blotting, 2D‐PAGE, and liquid chromatography–mass spectrometry. The results showed that heterozygous mutation carriers expressed both mutated and wild‐type DSG2 proteins. These findings were consistent with the results obtained by immunohistochemistry of endomyocardial biopsies and epidermal tissue of mutation carriers, which indicated a normal cellular distribution of DSG2. The results suggested a dominant‐negative effect of the mutated DSG2 proteins because they were incorporated into the desmosomes.  相似文献   
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