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Glucagon-like polypeptide 1 (GLP-1) may be amajor enterogastrone, slowing gastric emptying whenreleased by intestinal nutrients. In six conscious dogs,we studied the effects of GLP-1, on antropyloric motility, gastric emptying, and transpyloricflow after instillation of 500 ml of saline into thestomach. The meal was given and recordings were started15 min after intravenous bolus and infusion of either saline or three different doses of GLP-1.Intravenous GLP-1 produced a dose-related retardation ofgastric emptying associated with a decrease in thenumber and volume of flow pulses in comparison tosaline. This change in transpyloric flow was associatedwith an inhibition of antropyloric pressure waves, astimulation of isolated pyloric pressure waves, and anincrease in basal pyloric tone induced by intravenous GLP-1 infusion. Our findings show that GLP-1has a potent dose-dependent inhibitory effect ontranspyloric flow and gastric emptying. This effect istemporally associated with inhibition of antralpumping and stimulation of pyloricbraking mechanisms.  相似文献   
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Coronary remodeling and plaque composition were compared between focal and diffuse coronary lesions. Negative remodeling and fibrous and calcified plaque compositions contribute to stenosis development in diffuse lesions more frequently than in focal lesions.  相似文献   
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Compared with men, women may have a worse prognosis after native coronary revascularization. However, the influence of gender on clinical outcomes after saphenous vein graft (SVG) stenting is unknown. The purpose of this study was to compare early and 1-year clinical outcomes between men and women after stent implantation in SVG. A total of 1,199 consecutive patients with 1,858 SVG lesions were studied. Procedural success, in-hospital events, and late clinical outcomes were compared between men (n = 951) and women (n = 248). Overall procedural success was similar between men and women (97% vs 96%, p = NS). However, in-hospital (3.2% vs 1.6%, p = 0.07) and 30-day cumulative (4.4% vs 1.9%, p = 0.02) mortality rates were higher in women than in men. In addition, women had a higher incidence of vascular complications (12% vs 7.3%, p = 0.006) and postprocedural acute renal failure (8.1% vs 4%, p = 0.02). At 1-year follow-up, mortality was 13% in women and 11% in men (p = NS) and target lesion revascularization was 18% versus 23%, respectively (p = NS). By multivariate regression analysis, independent correlates of in-hospital mortality were female gender (odds ratio [OR] 3.6, confidence interval [CI] 1.0 to 12.5, p = 0.05) and left ventricular ejection fraction (OR 0.9, CI 0.9 to 1.0, p = 0.01). Female gender was found to predict 30-day mortality (OR 2.5, CI 1.1 to 5.5, p = 0.02). The sole predictor of 1-year mortality was diabetes mellitus (OR 1.6, CI 1.1 to 2.3, p = 0.01). This study shows that women compared with men treated with stent implantation in SVG lesions have (1) a trend toward higher in-hospital mortality, (2) higher risk of 30-day mortality, (3) increased incidence of vascular complications and postprocedure acute renal failure, and (4) similar 1-year clinical outcome.  相似文献   
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We previously found that contrast-induced nephropathy (CIN) complicating percutaneous coronary intervention adversely affects patients with chronic kidney disease (CKD). Therefore, we further investigated whether the predictors and outcome of CIN after percutaneous coronary intervention differ among patients with versus without CKD. Among 7,230 consecutive patients, CIN (>or=25% or >or=0.5 mg/dl increase in preprocedure serum creatinine 48 hours after the procedure) developed in 381 of 1,980 patients (19.2%) with baseline CKD (estimated glomerular filtration rate [eGFR] <60 ml/min/1.73 m(2)) and in 688 of 5,250 patients (13.1%) without CKD. Decreased eGFRs, periprocedural hypotension, higher contrast media volumes, lower baseline hematocrit, diabetes, pulmonary edema at presentation, intra-aortic balloon pump use, and ejection fraction <40% were the most significant predictors of CIN in patients with CKD. Apart from intra-aortic balloon pump use, predictors of CIN in patients without CKD were the same as mentioned, plus older age and type of contrast media. Regardless of baseline renal function, CIN correlated with longer in-hospital stay and higher rates of in-hospital complications and 1-year mortality compared with patients without CIN. By multivariate analysis, CIN was 1 of the most powerful predictors of 1-year mortality in patients with preexisting CKD (odds ratio 2.37, 95% confidence interval 1.63 to 3.44) or preserved eGFR (odds ratio 1.78; 95% confidence interval 1.22 to 2.60). Thus, regardless of the presence of CKD, baseline characteristics and periprocedural hemodynamic parameters predict CIN, and this complication is associated with worse in-hospital and 1-year outcomes.  相似文献   
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BACKGROUND: Recurrent abdominal pain (RAP) affects many children, especially those affected by beta-thalassaemia major. The role of Helicobacter pylori is still unclear in children with RAP. OBJECTIVES: The aim of the present study was the comparison of beta-thalassaemia major patients and normal controls with RAP in H. pylori infection. The factors influencing H. pylori prevalence were also investigated. METHODS: A series of 50 beta-thalassaemia major cases (30 female, 20 male; aged 6-25 years) and 50 age-matched and sex-matched controls, both presenting with RAP, were recruited during a period of 18 months. The study participants were obtained through a multistage random sampling method among those that met Apley's criteria. All the patients and controls had undergone diagnostic oesophagogastroduodenoscopy with biopsy. H. pylori infection was confirmed by two histopathological examinations on an endoscopy sample and a rapid urease test. RESULTS: H. pylori infection in thalassaemic patients was more common than in controls [34/50 (68%) versus 30/50 (60%)], but this higher frequency was not statistically significant. A clear relationship was found between the prevalence of H. pylori and age, duration of transfusion/chelation programmes, pain duration and splenectomy. In contrast, H. pylori did not correlate with abdominal pain characteristics, blood group, serum ferritin level and pathology of the upper gastrointestinal tract. The most frequent endoscopy abnormality was gastritis (72%). Nausea and heartburn were the leading associated symptoms. CONCLUSION: The high prevalence of H. pylori infection suggests that H. pylori should be remembered as a probable cause of RAP in beta-thalassaemia major patients.  相似文献   
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