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81.
Esam H. Alhamad Mohammed Al-Ghonaim Hussam F. Alfaleh Joseph P. Cal Nazmi Said 《Journal of thoracic disease》2014,6(6):606-616
Background
Information regarding lung function parameters and functional capacity in renal failure and post renal transplantation patients with pulmonary hypertension (PH) is limited. The purpose of this study was to examine the clinical characteristics of patients with PH who were receiving hemodialysis (HD) or peritoneal dialysis (PD) or who had undergone renal transplantation.Methods
A prospective study was performed on 116 patients (HD =55, PD =17, and post renal transplantation =44) who underwent Doppler echocardiography. PH was defined as systolic pulmonary artery pressure (SPAP) ≥40 mmHg. Demographic information, clinical characteristics, pulmonary function tests (PFTs) and the six-minute walk test (6MWT) were collected and compared between the patients with and without PH.Results
Twelve (21.8%) patients receiving HD, four (23.5%) patients receiving PD, and eight (18.2%) post renal transplantation patients had PH. In the HD group, the physiological indicators (including pulmonary function test parameters, the final Borg score, and walking distance during the 6MWT) were all significantly lower in the patients with PH compared with those without PH (all P<0.0001). However, in the PD and post renal transplantation groups, no significant differences were noted in the demographic characteristics or in the physiological parameters when the PH patients were compared with those without PH (all P>0.05).Conclusions
Among HD patients, marked aberrations in PFT results or walking distance may identify a subset of patients suffering from PH. 相似文献82.
83.
Anne‐Maree Kelly Oene Van Meer Gerben Keijzers Justina Motiejunaite Peter Jones Richard Body Simon Craig Mehmet Karamercan Sharon Klim Veli‐Pekka Harjola Franck Verschuren Anna Holdgate Michael Christ Adela Golea Colin A. Graham Jean Capsec Cinzia Barletta Luis Garcia‐Castrillo Win S. Kuan Said Laribi 《Internal medicine journal》2020,50(2):200-208
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N Al-Aidroos CP Said NB Turk-Browne 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(36):14675-14680
Top-down attention is an essential cognitive ability, allowing our finite brains to process complex natural environments by prioritizing information relevant to our goals. Previous evidence suggests that top-down attention operates by modulating stimulus-evoked neural activity within visual areas specialized for processing goal-relevant information. We show that top-down attention also has a separate influence on the background coupling between visual areas: adopting different attentional goals resulted in specific patterns of noise correlations in the visual system, whereby intrinsic activity in the same set of low-level areas was shared with only those high-level areas relevant to the current goal. These changes occurred independently of evoked activity, persisted without visual stimulation, and predicted behavioral success in deploying attention better than the modulation of evoked activity. This attentional switching of background connectivity suggests that attention may help synchronize different levels of the visual processing hierarchy, forming state-dependent functional pathways in human visual cortex to prioritize goal-relevant information. 相似文献
87.
Kaya MG Uyarel H Akpek M Kalay N Ergelen M Ayhan E Isik T Cicek G Elcik D Sahin O Cosgun SM Oguzhan A Eren M Gibson CM 《The American journal of cardiology》2012,109(4):486-491
Elevated uric acid (UA) levels have been associated with cardiovascular disease in epidemiologic studies. The relation between UA levels and long-term outcomes in patients with ST-segment elevation myocardial infarction who undergo primary percutaneous coronary intervention is not known. Data from 2,249 consecutive patients with ST-segment elevation myocardial infarction who underwent primary percutaneous coronary intervention were evaluated. Patients were divided into 2 groups with high or low UA using upper limits of normal of 6 mg/dl for women and 7 mg/dl for men. There were 1,643 patients in the low-UA group (mean age 55.9 ± 11.6 years, 85% men) and 606 patients in the high-UA group (mean age 60.5 ± 12.6 years, 76% men). Serum UA levels were 8.0 ± 1.5 mg/dl in the high-UA group and 5.2 ± 1.0 mg/dl in the low-UA group (p <0.001). The in-hospital mortality rate was significantly higher in patients with high UA levels (9% vs 2%, p <0.001), as was the rate of adverse outcomes in patients with high UA. The mean follow-up time was 24.3 months. Cardiovascular mortality, reinfarction, target vessel revascularization, heart failure, and major adverse cardiac events were all significantly higher in the high-UA group. In a multivariate analyses, high plasma UA levels were an independent predictor of major adverse cardiac events in the hospital (odds ratio 2.03, 95% confidence interval 1.25 to 3.75, p = 0.006) and during long-term follow-up (odds ratio 1.64, 95% confidence interval 1.05 to 2.56, p = 0.03). In conclusion, high UA levels on admission are independently associated with in-hospital and long-term adverse outcomes in patients with ST-segment elevation myocardial infarction who undergo primary percutaneous coronary intervention. 相似文献
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David P. Martin Amit Badhwar Devang V. Shah Said Rizk Stephen N. Eldridge Darcy H. Gagne Amit Ganatra Roger E. Darois Simon F. Williams Hsin-Chien Tai Jeffrey R. Scott 《The Journal of surgical research》2013
Background
Phasix mesh is a fully resorbable implant for soft tissue reconstruction made from knitted poly-4-hydroxybutyrate monofilament fibers. The objectives of this study were to characterize the in vitro and in vivo mechanical and resorption properties of Phasix mesh over time, and to assess the functional performance in a porcine model of abdominal hernia repair.Materials and methods
We evaluated accelerated in vitro degradation of Phasix mesh in 3 mol/L HCl through 120 h incubation. We also evaluated functional performance after repair of a surgically created abdominal hernia defect in a porcine model through 72 wk. Mechanical and molecular weight (MW) properties were fully characterized in both studies over time.Results
Phasix mesh demonstrated a significant reduction in mechanical strength and MW over 120 h in the accelerated degradation in vitro test. In vivo, the Phasix mesh repair demonstrated 80%, 65%, 58%, 37%, and 18% greater strength, compared with native abdominal wall at 8, 16, 32, and 48 wk post-implantation, respectively, and comparable repair strength at 72 wk post-implantation despite a significant reduction in mesh MW over time.Conclusions
Both in vitro and in vivo data suggest that Phasix mesh provides a durable scaffold for mechanical reinforcement of soft tissue. Furthermore, a Phasix mesh surgical defect repair in a large animal model demonstrated successful transfer of load bearing from the mesh to the repaired abdominal wall, thereby successfully returning the mechanical properties of repaired host tissue to its native state over an extended time period. 相似文献90.
S. Said Kökçam Şakir Tekin Adil Kartal Murat Ayaz Mustafa Şahin Fahreddin Acar Murat Çakir Yusuf Küçükbağriaçik 《The Journal of surgical research》2013