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101.
BackgroundAn increase in the pulmonary capillary wedge pressure (PAWP) has been shown to impact on the inherent relationship between the pulmonary arterial compliance (PAC) and pulmonary vascular resistance (PVR), thus augmenting the pulsatile relative to the resistive load of the right ventricle. However, the PAWP comprises the integration of both the steady and the pulsatile pressure components. We sought to address the differential impact of the these distinct PAWP components on the PAC–PVR relationship in a cohort of patients with heart failure. Methods and ResultsThe study population consisted of 192 patients with hemodynamic findings diagnostic for heart failure. Off-line analysis was performed using the MATLAB software. The steady and pulsatile PAWP components were calculated as mid-A pressure and mean pressure during the V-wave oscillation, respectively. The PAC and PVR were hyperbolically and inversely associated and the subgroup of patients with PAWP above the median (>18 mm Hg) displayed a significant left and downward shift of the curve fit (P < .001). The shift in the PAC–PVR fit between patients with higher versus low steady PAWP was not significant (P = .43). In contrast, there was a significant downward and leftward shift of the PVR–PAC curve fit for the subgroup with a higher pulsatile PAWP (P < .001). Furthermore, only the pulsatile PAWP was significantly associated with the time-constant of the pulmonary circulation, assessed as the PAC × PVR product (P < .001).ConclusionsIn patients with heart failure, the pulsatile rather than the steady PAWP component stands for the previously documented shift of the PAC–PVR relationship occurring at an elevated PAWP.  相似文献   
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ObjectivesThe relation between aetiology and structural changes of the pancreas in patients with chronic pancreatitis (CP) is not fully understood. Earlier studies are limited by focusing on selected factors in studies of limited sample size. We aimed to use a large dataset to explore associations between aetiology and pancreatic morphology in CP.MethodsSubjects with definite or probable CP according to the M-ANNHEIM diagnostic criteria were included in this multicentre cross-sectional observational study and assessed using a standardized and validated CP imaging system. We performed multivariate logistic regression to analyse if aetiological factors adjusted for covariates were independently associated with morphological pancreatic features.ResultsWe included 959 patients (66% males). Mean (SD) age was 55 (14) years. Pancreatic structural changes were found in 94% of the subjects: 67% had calcifications, 59% main pancreatic duct dilatation, 33% pseudo-cysts and 22% pancreatic atrophy. Alcohol abuse was independently associated with pancreatic calcifications (odds ratio (OR, [95% CI]); 1.61, [1.09, 2.37]) and focal acute pancreatitis (OR; 2.13, [1.27, 3.56]), whereas smoking was independently associated with more severe calcifications (OR; 2.09, [1.34, 3.27]) and involvement of the whole gland (OR; 2.29, [1.61, 3.28]). Disease duration was positively associated with calcifications (OR; (per year) 1.05 [1.02, 1.08]) and pancreatic atrophy (OR; 1.05 [1.02, 1.08]) and negatively associated with focal acute pancreatitis (OR 0.91, [0.87, 0.95] and pseudo cysts (OR; 0.96, [0.93, 0.98]).ConclusionIn this large-scale study, etiological risk factors and disease duration in CP were independently associated with specific structural pancreatic imaging changes.  相似文献   
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Background: Cryoablation of accessory pathways (APs) is effective and very safe in children, as previously reported by our group. The aim of this retrospective study was to evaluate the current efficacy of 3D non-fluoroscopic cryoablation of right sided APs in children, comparing results obtained with the Ensite VelocityTM and the more recent Ensite PrecisionTM 3D mapping systems. Methods and Results: From January 2016 to December 2019, 102 pediatric patients [mean age 12.5 ± 2.8, 62 males (61% of total cohort)] with right APs underwent 3D non-fluoroscopic transcatheter cryoablation at our Institution. Fifteen (14.7%) patients had previously undergone catheter ablation. Acute procedural success rate was 95.1% (n = 97). No significant differences were detected in acute success rates achieved with Ensite VelocityTM or Ensite PrecisionTM systems nor between manifest (94%) and concealed APs (100%). No permanent complications occurred. During follow-up (428 ± 286 days, median 396 days [interquartile range 179-713]), 19 patients (19.6%) had recurrences. Recurrences were more frequent for parahissian/anterior APs compared to midseptal/posterior and lateral APs (p = 0.043). Recurrences were not related to the Ensite system used. A redo ablation procedure was attempted in 13 cases, 11 cryoablation and 2 radiofrequency ablations: the former was successful in 10 cases out of 11 (90.9%). Conclusion: 3D cryoablation of right-sided APs is associated with a very high acute success rate with limited use of fluoroscopy, resulting in great benefit to the children. Recurrence rates are not high and patients can be retreated with cryo-energy with higher success rates.  相似文献   
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BACKGROUND: Different theories have been presented to explain how atrophic gastritis may lead to gastric cancer development. One contributing factor could be impaired function of the gastric mucosal barrier. The aim of this study was to investigate if there are changes in gastric mucosal permeability to sucrose in atrophic gastritis. METHODS: The study comprised 22 patients with atrophic gastritis and 21 normal controls. Gastritis was classified according to the Sydney system from endoscopic biopsies of the gastric corpus and antrum. All subjects were exposed to oral sucrose load (100 g), and the fraction of sucrose excreted in urine was measured by gas chromatography-mass spectrometry. RESULTS: The fraction of sucrose excreted in urine after oral load was significantly increased in atrophic gastritis compared with controls (median 0.08 vs. 0.04%; p = 0.003). Sucrose excretion was positively related to the degree of chronic inflammation (median fraction excreted: mild inflammation 0.06%, moderate inflammation 0.08%, severe inflammation 0.18%; p = 0.04) rather than to the degree of atrophy in the gastric mucosa. Occurrence of intestinal metaplasia was also associated with significantly higher sucrose excretion. However, in multivariate analysis, including intestinal metaplasia, only the degree of inflammation was positively related to sucrose excretion. CONCLUSION: Atrophic gastritis is associated with increased sucrose permeability, suggesting paracellular leakage of the gastric mucosa. This leakage seems to be related to the degree of inflammation rather than the degree of atrophy. The findings may have implications for the diseases and complications associated with atrophic gastritis.  相似文献   
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Objective : This pilot study aimed to determine the feasibility of a novel, low‐cost program to get remote schools started in gardening and nutrition activities, for a lower cost than existing models, and without on‐the‐ground horticultural support. Methods : A multi‐site, mixed methods case study was undertaken, in which four remote schools were shipped gardening materials and a nutrition and cooking resource, and provided with horticultural support by phone and email. A support register and teacher surveys were used for four months of evaluation. Results : The study demonstrated that the program is feasible, and may be associated with an increase from baseline in student's time spent cooking, gardening and on related classroom activities. Conclusions : The program was delivered economically without the need for on‐the‐ground staff, in a manner that was acceptable to teachers. Implications : This model may have application in remote schools throughout Australia, where there is a need to alter health impacting behaviours in high‐risk populations. Lengthier program evaluation times and further resource development may be worth investigating in the future.  相似文献   
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