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Background: Barrett esophagus (BE) is a premalignant condition resulting from chronic acid gastroesophageal reflux and is associated with increased epithelial cell proliferation. Elimination of acid reflux might decrease cancer risk by affecting cell proliferation in BE. The effect of elimination of acid reflux on epithelial cell proliferation in BE was studied. Methods: Forty-five patients with long segment Barrett esophagus were treated in a randomized 2-year follow-up study with either omeprazole 40 mg b.i.d. (OME) or ranitidine 150 mg b.i.d. (RAN) and were compared for the effect on epithelial cell proliferation. Biopsies were taken 3 cm above the GE junction and just below the Z-line, at 0, 3, 9, and 24 months. Epithelial cell proliferation was determined by in vitro labeling with 5-bromo-2-deoxyuridine and immunohistochemistry. Labeling indices (LI) were established for luminal and crypt epithelium separately. Ambulatory 24-h esophageal pH-metry was performed at 0 and 3 months. Comparisons were made for the timeframes 0-3 months, 3-24 months, and 0-24 months. Results: OME reduced mean acid reflux to 0.1%/24 h, RAN to 9.4%. In the distal and the proximal biopsies, change in LI after 3 months was n.s. at either level for both treatments. In the distal biopsies (OME 22, RAN 23 patients) luminal LI increased significantly for RAN from 3 to 24 months (+ 12.64% month, mean area under the curve (AUC)), while that for OME remained stable, RAN versus OME P < 0.05. Crypt LI increased in both groups, only in RAN significantly so (+ 30.75% month), RAN versus OME n.s. In the proximal biopsies luminal LI at 24 months (OME 20, RAN 21 patients) had increased slightly but not significantly in RAN (+ 8.86% month), RAN versus OME n.s., whereas in the crypts LI in OME it had increased significantly (+ 28.80% month), OME versus RAN n.s. Conclusion: Elimination ofacid reflux resulted in a stabilization of luminal cell proliferative activity of Barrett epithelium in the distal esophagus, whereas this activity increased during continued acid reflux. Whether this finding has any implication for the cancer risk in Barrett esophagus remains to be seen.  相似文献   
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Corticosteroids are a mainstay of topical therapy for psoriasis. While efficacious and relatively safe when used carefully, the potential for side effects, notably skin atrophy and adrenal suppression, have been associated with excesses in potency, prolonged or widespread use. The International Psoriasis Council Working Group on Topical Therapy has reviewed the efficacy and safety of topical corticosteroids and recommends strategies for safe, long‐term use of these agents.  相似文献   
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Background  

Gastrojejunostomy (GJJ) and stent placement are the most commonly used palliative treatments for malignant gastric outlet obstruction (GOO). In a recent randomized trial, stent placement was preferred in patients with a relatively short survival and GJJ in patients with a longer survival. As health economic aspects have only been studied in general terms, we estimated the cost of GJJ and that of stent placement in such patients.  相似文献   
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Many chronic obstructive pulmonary disease (COPD) patients use their inhaler ineffectively and there is a trend towards increased inhaler resistance. We wanted to answer two questions: Is there a difference in preference and ease of use between Diskus (DK) and Handihaler (HH)? How acceptable are inhalation resistances? Sixty COPD patients, naive to DK and HH, but experienced in the use of other inhalers, had to read the instruction leaflet and demonstrate their inhalation technique. If errors were made, instruction was given and inhalation technique was checked again. Patients had to state a preference for DK or HH. Subsequently they inhaled through a range of resistances and scored the acceptability. There was no difference in the number of instructions needed for both inhalers. One third inhaled perfectly after reading the instruction leaflet, which increased to 85% after one instruction. More patients preferred the DK (43) than the HH (16). With decreasing resistance acceptability increases, but it reaches a plateau. Patients have a clear preference for the DK. There is no difference in the number of instructions needed to obtain a perfect inhalation technique, but for some patients one instruction is not enough. The trend to increase the resistance of inhalers has reached a critical point with regard to acceptability.  相似文献   
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The incidence of disturbed sleep is strongly increased in healthy and demented elderly. Age-related alterations in the circadian timing system appear to contribute strongly to these problems. With increasing age, a lack of input to the suprachiasmatic nucleus (SCN), the biological clock of the brain, may accelerate de-activation of neurons involved in the generation of 24-h rhythm or output of this rhythm. This process appears to be reversible, since supplementation of stimuli that impinge on the SCN can re-activate these neurons and ameliorate disturbances in the sleep–wake rhythm.  相似文献   
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This study comprised 103 preterm infants with a gestational age less than 33 weeks who were born in Tampere University Hospital and who were followed up to two years of age. Sixty-four perinatal variables were compared to ultrasound findings in the neonatal period and neurologic handicap at the age of two years. Duration of hypocarbia (PCO2 < or = 30 mmHg) during the first 72 h and hyperbilirubinemia (the mean level of serum total bilirubin) at three days of age were independently and significantly related to periventricular leukomalacia, but not directly to cerebral palsy. The only perinatal variables related independently and significantly to cerebral palsy at two years of age were periventricular leukomalacia and ventriculomegaly. According to these results, periventricular leukomalacia was the main predictor of cerebral palsy in preterm infants. In addition to hypocarbia, hyperbilirubinemia may also be involved in the pathogenesis of extensive (severe cystic) periventricular leukomalacia.  相似文献   
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