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INTRODUCTION: Endothelin receptor antagonism has become an important component in the treatment of pulmonary arterial hypertension (PAH) associated with connective tissue disease (CTD). The purpose of this study was to analyse the safety and effectiveness of sitaxsentan, a selective antagonist of the ET(A) receptor, in a cohort of patients with PAH and CTD. Short-term clinical and haemodynamic effects and longer-term follow-up data are presented. METHODS: A post hoc subgroup analysis was performed on 42 patients who had PAH associated with CTD, out of a group of 178 patients enrolled in a 12-week, double-blind, randomised clinical trial of sitaxsentan versus placebo. Data from 33 patients assigned to sitaxsentan 100 mg or 300 mg daily were pooled and compared with nine placebo-treated patients. There were 41 patients entered into the blinded extension study, in which all patients received either 100 mg or 300 mg sitaxsentan once daily. RESULTS: Patients treated with sitaxsentan had a mean (SD) increase in 6 minute walk distance of 20 (5) m from baseline to week 12 (p = 0.037), whereas the placebo group had a decrease of 38 (84) m, resulting in a placebo-subtracted treatment effect of 58 m (p = 0.027). Parallel improvements in quality of life and haemodynamics were also observed. No patient discontinued their drug during the 12-week trial. In the blinded extension study (median treatment duration 26 weeks), more patients were in functional class I-II than in III-IV (p<0.001) at the end of the study compared with the start of active therapy. Elevation of hepatic transaminase levels occurred in two patients. CONCLUSIONS: Sitaxsentan appears to be efficacious in patients with PAH associated with CTD.  相似文献   
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A 77-year-old man had aorto-iliac bypass for an abdominal aortic aneurysm (AAA). This was complicated by occlusion that needed extension of the graft to the right femoral artery. He was unable to move his right leg with numbness after surgery. This was caused by extensive lumbosacral plexopathy on the right side. Lumbosacral plexopathy is uncommon because the plexus has a rich blood supply. The incidence of ischaemic lumbosacral plexopathy is higher with re-operative and emergency AAA reconstruction. This may predispose the lumbosacral plexus to ischaemic injury. Consideration should be given to maintaining retrograde perfusion of the internal iliac artery.  相似文献   
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Journal of Digital Imaging - Hair and ruler mark structures in dermoscopic images are an obstacle preventing accurate image segmentation and detection of critical network features. Recognition and...  相似文献   
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This work involves studying the effects of applying various designed hot-rolling strategies, using the uniaxial hot compression regimes of the Gleeble 3500 thermo-mechanical simulator on the microstructure, flow behavior, and productivity of Ti-6Al-4V alloy. These strategies were then practically implemented using a rolling mill to produce finished sheets with a thickness of 3 mm. The tensile properties of these finished Ti-6Al-4V sheets were examined, aiming at attaining the optimum rolling strategy conditions that result in upgrading the mechanical performance of the alloy. The undertaken hot-rolling strategies can be divided into two main groups; both comprise applying a total amount of deformation of 75% at a constant strain rate of 0.1 s−1. The first group, isothermal hot rolling regime (IR), includes three strategies and involves applying the total amount of deformation at constant temperatures, i.e., 900, 800, and 750 °C. The second group, non-isothermal hot rolling regime (NIR), includes three strategies and involves partitioning the total amount of deformation into multi-step deformation at variable temperatures in a range of 900–750 °C. The dynamic flow softening is dominant in all IR strategies after the flow stress attains the peak at a low strain value. Then, dynamic flow softening occurs due to the dynamic recrystallization and α phase spheroidization, while a combination of flow softening and hardening takes place on the different passes of the NIR strategies. The designed hot-rolling strategies result in finished sheets with a fine multimodal microstructure that fructifies different mechanical properties that can be employed for different industrial purposes.  相似文献   
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