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1.
Yinlei
Wen Huaguang Zhang Hanguang Su He Ren 《Optimal control applications & methods.》2020,41(4):1233-1250
In this article, a model-free off-policy reinforcement learning algorithm is applied to address the optimal tracking problem based on multiplayer non-zero-sum games for discrete-time linear systems. In contrast to the traditional method and the policy iteration method for solving the optimal tracking problems, the proposed algorithm operates with the system data rather than the knowledge of the system dynamics. For performing the proposed algorithm, an auxiliary augmented system is constructed via assembling the original system and the reference trajectory while a discount factor is introduced into the performance indexes. It is analyzed that the solutions of the proposed algorithm converge to the Nash equilibrium and the result is not influenced by the probing noise. Two simulations are presented to verify the feasibility and effectiveness of the proposed algorithm. 相似文献
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Platelet function has been described by many laboratory assays, and PL-11 is a new point-of-care platelet function analyzer based on platelet count drop method, which counts platelet before and after the addition of agonists in the citrated whole blood samples. The present study sought to compare PL-11 with other three major more established assays, light transmission aggregometry (LTA), VerifyNow? aspirin system and thromboelastography (TEG), for monitoring the short-term aspirin responses in healthy individuals. Ten healthy young men took 100?mg/d aspirin for 3-day treatment. Platelet function was measured via PL-11, LTA, VerifyNow and TEG, respectively. The blood samples were collected at baseline, 2 hour, 1 day during the aspirin treatment and 1 day, 5?±?1 days, 8?±?1 days after the aspirin withdrawal. Moreover, 90 additional healthy subjects were recruited to establish a reference range for PL-11. Platelet function of healthy subjects decreased significantly 2 hours after 100?mg/d aspirin intake and began to recover during 4–6 days after the aspirin withdrawal. Correlations between methods were PL-11 vs. LTA (r?=?0.614, p?<?0.01); PL-11 vs. VerifyNow (r?=?0.829, p?<?0.01); PL-11 vs. TEG (r?=?0.697, p?<?0.001). There was no significant bias between PL-11 and LTA at baseline (bias?=?1.94%, p?=?0.804) using Bland-Altman analysis, while the data of PL-11 were significantly higher than LTA (bias?=?24.02%, p?<?0.001) during the aspirin therapy. The reference range for PL-11 in healthy young individuals was from 66.8 to 90.5% (95%CI). When aspirin low-responsiveness was defined as LTA?>?20%, the cut-off values for each method were, respectively: PL-11?>?50%, VerifyNow?>?533 ARU, TEG?>?60.2%. The results of different platelet function assays were uninterchangeable for monitoring aspirin response and correlations among them were also varied. Correlations among PL-11 and other three major assays suggested the ability of PL-11 to assess the treatment effects of aspirin. But a large cohort study is needed to confirm the cut-off value of aspirin response detected by PL-11. 相似文献
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Annals of Nuclear Medicine - Cardiac amyloidosis is a rare disease characterized by amyloid heart deposits and is usually a part of systemic amyloidosis, in relation to systemic light chain (AL)... 相似文献
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Wei Zhang Zheng Li Feng-Qing Xu Ya-Shuo Ren Shuang-Wang Xu Tong-Sheng Wang 《Journal of Asian natural products research》2019,21(5):426-434
Two new 11-methoxyl substituted triterpenoids, named as mimengosides J (1) and K (2), along with seven known compounds, were isolated from the fruits of Buddleja lindleyana. Their structures were elucidated on the basis of spectroscopic analysis. In addition, the new ones were evaluated for protective effects against damage of SH-SY5Y cells induced by 1-methyl-4-phenylpyridinium ion (MPP+) and the results indicated that those may be one of the candidate compositions of Buddleja lindleyana for the treatment of neurodegenerative disease.
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目的 探讨腰硬联合(CSEA)及患者自控镇痛(PCEA)对产程及分娩结局的影响。方法 随机选取2014年1~12月足月待产、无妊娠合并症和并发症初产妇996例,其中503例产妇于活跃期实施CSEA+PCEA镇痛(分娩镇痛组),493例未行分娩镇痛(对照组),分别记录并比较两组产妇各产程时间、子宫收缩、镇痛效果、运动神经阻滞程度、产程中缩宫素的使用率、产后出血率、羊水Ⅲ度污染率、新生儿Apgar评分、产钳助产和剖宫产率。结果 分娩镇痛组第一产程、第二产程较对照组有所延长,差异有统计学意义(P<0.05);第三产程无明显改变;子宫收缩力减弱;分娩镇痛组较对照组镇痛效果显著,差异有统计学意义(P<0.05);运动阻滞程度低;缩宫素使用率、产后出血率、羊水Ⅲ度污染率、及新生儿Apgar评分及产钳助产和剖宫产率两组比较,差异均无统计学意义(P>0.05)。结论 腰硬联合分娩镇痛可能会使第一产程、第二产程延长,对子宫收缩力有一定的影响,但并未增加缩宫素的使用率及产钳助产和剖宫产率,其镇痛效果显著,运动阻滞程度低,对分娩结局无不良影响。 相似文献
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This meta-analysis examined whether early decompressive craniectomy (DC) can improve control of intracranial pressure (ICP) and mortality in patients with traumatic brain injury (TBI).Medline, Cochrane, EMBASE, and Google Scholar databases were searched until May 14, 2015, using the following terms: traumatic brain injury, refractory intracranial hypertension, high intracranial pressure, craniectomy, standard care, and medical management. Randomized controlled trials in which patients with TBI received DC and non-DC medical treatments were included.Of the 84 articles identified, 8 studies were selected for review, with 3 randomized controlled trials s having a total of 256 patients (123 DCs, 133 non-DCs) included in the meta-analysis. Patients receiving DC had a significantly greater reduction of ICP and shorter hospital stay. They also seemed to have lower odds of death than patients receiving only medical management, but the P value did not reach significance (pooled odds ratio 0.531, 95% confidence interval 0.209–1.350, Z = 1.95, P = 0.183) with respect to the effect on overall mortality; a separate analysis of 3 retrospective studies yielded a similar result.Whereas DC might effectively reduce ICP and shorten hospital stay in patients with TBI, its effect in decreasing mortality has not reached statistical significance. 相似文献
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目的:解析加拿大Chochinov疾病终末期患者尊严模型在中华文化情境下的适用性,并基于此对模型进行调适。方法:采用内容分析法,按照选定分析范围、抽取样本、确定分析单位和分析框架、资料分析四步完成。首先检索中、英文数据库中以中华文化背景下临终尊严为主题的文献,然后以尊严模型为框架对文献内容进行编码、归纳和分析。结果:尊严模型包含的多数主题符合我国临终患者的认知,如身体功能、医疗不确定性、死亡焦虑、隐私界限、照护要旨、他人负担、后事担忧等。但也出现了矛盾的主题,如忍受痛苦、自主性等,以及新的主题,包括家庭支持、病耻感和财务担忧。结论:加拿大版疾病终末期患者尊严模型并不完全符合中国文化,调适后的尊严模型更具我国文化特色,但仍需实证研究对模型进行验证。 相似文献