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Elevated serum uric acid (SUA) levels have been associated with several cardiovascular risk factors and the progression of coronary artery disease. In the setting of acute myocardial infarction, increasing evidence suggests that high SUA levels could be related to adverse outcomes. Interestingly elevated SUA levels have been linked to endothelial dysfunction, inflammation and oxidative stress. The aim of this review is to discuss the potential negative effects of SUA in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention, analyzing the possible underlying pathophysiological mechanisms.  相似文献   
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目的:探讨基于肿瘤浸润深度及大小的TTS评分系统对可切除胃癌患者预后判断的价值。方法:选择行根治性切除的234例胃癌患者为研究对象。根据肿瘤浸润深度(T分期)和肿瘤大小构建TTS评分系统,分为TTS 0级、1级、2级,代表肿瘤侵袭性逐渐升高。通过Cox多因素模型分析TTS评分系统作为预后判断工具的可行性。结果:T1-T4期患者肿瘤的平均大小分别为(3.3±2.7)cm、(4.1±3.1)cm、(6.6±3.1)cm、(9.4±4.9)cm。单因素分析显示,肿瘤浸润深度与肿瘤大小、淋巴结转移、TNM分期、淋巴浸润和血管浸润显著相关(P<0.01)。ROC曲线显示,45 mm为肿瘤大小的最佳界值,可有效区分患者是否存在淋巴结转移,曲线下面积(area under curve,AUC)为0.762。综合肿瘤大小的临界值和肿瘤浸润深度,构建TTS评分系统,TTS 0级、TTS 1级和TTS 2级的患者5年生存率分别为95.6%、83.3%和70.2%,两两比较后发现,不同TTS状态患者的生存率之间均存在显著差异(P<0.01)。Cox多因素分析发现,TTS评分是影响患者预后的独立性危险因素(P<0.05)。结论:本研究根据肿瘤浸润深度和大小构建了TTS评分系统,并证明了TTS评分与胃癌患者的预后密切相关。  相似文献   
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BackgroundHigh injury rates following anterior cruciate ligament reconstruction (ACLR) motivate the need to better understand lingering movement deficiencies following return to sport. Athletic competition involves various types of sensory, motor, and cognitive challenges; however, postural control deficiencies during this spectrum of conditions are not well understood following ACLR.Research questionTo what extent is postural control altered following ACLR in the presence of sensory, motor, and cognitive challenges, and does postural control correlate with patient-reported symptoms?MethodsFourteen individuals following ACLR (4 m/10 f, 21.2 ± 2.4 yr, 76.9 ± 19.1 kg, 1.70 ± 0.14 m) and fourteen matched healthy controls (4 m/10 f, 21.2 ± 1.4 yr, 75.4 ± 15.3 kg, 1.70 ± 0.15 m) participated in the study. Participants completed single-leg balance, ACLR limb or matched side for controls, under four conditions: 1) eyes open, 2) eyes closed, 3) visual-cognitive dual task (i.e., reverse digit span), and 4) motor dual task (i.e., catching a ball). Sample entropy (SEn) was calculated for each balance condition to characterize regularity of center of pressure control. Participants also completed patient-reported outcomes to characterize self-reported knee function, symptoms, and fear. A mixed effects model tested for differences in SEn between balance conditions, and Spearman correlations tested for relationships between SEn and patient-reported outcomes.ResultsA significant Group-by-Condition interaction was detected (P = 0.043). While the motor dual task and eyes closed balance conditions were associated with the lowest SEn for both groups, only the visual-cognitive dual task condition demonstrated a significant difference between groups, with the ACLR group having lower SEn [95% confidence interval for ΔSEn: (0.03, 0.35)]. Lower KOOS-Sport scores were associated with decreased SEn for the ACLR group (ρ = 0.81, P < 0.001).SignificanceThese findings are consistent with ACLR individuals using a less automatic approach to postural control compared to controls, particularly when presented with a visual-cognitive challenge. Altered neuromuscular control persists well after ACLR surgery and can be related to patient-reported outcomes.  相似文献   
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In some diseases, such as multiple sclerosis, lesion counts obtained from magnetic resonance imaging (MRI) are used as markers of disease progression. This leads to longitudinal, and typically overdispersed, count data outcomes in clinical trials. Models for such data invariably include a number of nuisance parameters, which can be difficult to specify at the planning stage, leading to considerable uncertainty in sample size specification. Consequently, blinded sample size re-estimation procedures are used, allowing for an adjustment of the sample size within an ongoing trial by estimating relevant nuisance parameters at an interim point, without compromising trial integrity. To date, the methods available for re-estimation have required an assumption that the mean count is time-constant within patients. We propose a new modeling approach that maintains the advantages of established procedures but allows for general underlying and treatment-specific time trends in the mean response. A simulation study is conducted to assess the effectiveness of blinded sample size re-estimation methods over fixed designs. Sample sizes attained through blinded sample size re-estimation procedures are shown to maintain the desired study power without inflating the Type I error rate and the procedure is demonstrated on MRI data from a recent study in multiple sclerosis.  相似文献   
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ObjectiveTo compare the baseline clinical characteristics between patients with ROS1-positive and ALK-positive advanced non-small cell lung cancer (NSCLC), and the correlations of these subtypes with the distribution of metastases.MethodsWe compared the clinical characteristics and imaging features of patients with ROS1-positive and ALK-positive NSCLC using statistical methods.ResultsData for 232 patients were analyzed. Compared with ALK-positive NSCLC, ROS1-positive NSCLC was more likely to occur in women (71% vs 53%), and primary lesions ≤3 cm were more common in patients with ROS1-positive compared with ALK-positive NSCLC (58% vs 37%). There was no significant difference in the distribution of metastases between the two groups. Subgroup analysis within the ROS1-positive group showed that, compared with primary lesions >3 cm, primary lesions ≤3 cm were more likely to present as peripheral tumors (72% vs 43%) and more likely to exhibit non-solid density (44% vs 4%).ConclusionsAlthough ROS1-positive and ALK-positive NSCLCs show similar clinical features, the differences may help clinicians to identify patients requiring further genotyping at initial diagnosis.  相似文献   
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The particle size distribution significantly affects the material properties of the additively manufactured parts. In this work, the influence of bimodal powder containing nano- and micro-scale particles on microstructure and materials properties is studied. Moreover, to study the effect of the protective atmosphere, the test samples were additively manufactured from 316L stainless steel powder in argon and nitrogen. The samples fabricated from the bimodal powder demonstrate a finer subgrain structure, regardless of protective atmospheres and an increase in the Vickers microhardness, which is in accordance with the Hall-Petch relation. The porosity analysis revealed the deterioration in the quality of as-built parts due to the poor powder flowability. The surface roughness of fabricated samples was the same regardless of the powder feedstock materials used and protective atmospheres. The results suggest that the improvement of mechanical properties is achieved by adding a nano-dispersed fraction, which dramatically increases the total surface area, thereby contributing to the nitrogen absorption by the material.  相似文献   
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