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51.
Successfully explaining and replicating the complexity and generality of human and animal learning will require the integration of a variety of learning mechanisms. Here, we introduce a computational model which integrates associative learning (AL) and reinforcement learning (RL). We contrast the integrated model with standalone AL and RL models in three simulation studies. First, a synthetic grid‐navigation task is employed to highlight performance advantages for the integrated model in an environment where the reward structure is both diverse and dynamic. The second and third simulations contrast the performances of the three models in behavioral experiments, demonstrating advantages for the integrated model in accounting for behavioral data.  相似文献   
52.
分子靶向药物的出现显示出肿瘤治疗传统模式的重要进展。与传统放疗、化疗相比,分子靶向治疗因其特异性高、不良反应轻微,在恶性肿瘤个体化治疗中扮演重要角色。十五年来,分子靶向药物的出现,给肿瘤的治疗模式带来重大改变,也给临床医生带来新的挑战。准确把握分子靶向药物应用时机,获得最大临床效果,已成为肿瘤治疗领域关注热点。本文就非小细胞肺癌、消化系统肿瘤、乳腺癌、肾癌治疗中分子靶向药物如何选择应用时机进行阐述。  相似文献   
53.
将中南大学湘雅医学院2010级临床医学五年制197名学生随机分成两组,在医学影像学见习教学过程中分别应用影像存储及传输系统(PACS)教学法(98人)及传统读片教学法(99人),学期结束时对两组学生考试成绩进行分析,并对PACS组学生进行问卷调查及结果分析.统计数据显示,PACS组学生读片测验及卷面考试中,病例分析题成绩显著高于传统读片组,问卷调查显示PACS组学生大多数认可该教学方法.因此,应用PACS教学有助于提高学生的临床分析能力及主动学习的能力,是学生欢迎的教学方式.但对医学影像学基本知识的传授,应用PACS法较传统读片法并无明显优势.  相似文献   
54.
目前肝衰竭发病率和病死率仍然较高,肝衰竭成为威胁患者生命的严重疾病。基于肝脏具有强大再生能力,人工肝支持系统作为一种“过渡”措施,为肝衰竭患者的肝功能恢复赢得时间。人工肝支持系统根据性质不同分为非生物型人工肝、生物型人工肝和混合型人工肝。目前非生物型人工肝已在肝病治疗领域被广泛应用,但生物型及混合型人工肝的临床应用还存在很多问题需要进一步研究和解决。因此本文对人工肝的作用、临床应用现状、存在问题及研究进展进行综述。  相似文献   
55.
It is still controversial to what extent neocortical consolidated memories are susceptible of change by processes of reconsolidation and transformation throughout experience, and whether the medial temporal lobes are necessary for this update of semantic consolidated memories, as they are for episodic remembering. We hypothesize that patients with amnestic mild cognitive impairment (aMCI) who have deficits in episodic memory may also have difficulties in updating information on added new features of objects. Sixteen participants with aMCI and 20 healthy control participants performed a semantic word-to-picture task, in which they were asked to identify as belonging to a given semantic category NEW objects, that have incorporated novel features, as well as OLD items, semantically and visually SIMILAR items and UNRELATED items. Patients with aMCI made a greater percentage of errors than healthy controls. Participants globally made greater percentages of errors in difficult types of items, namely NEW and SIMILAR, as compared to easier ones, OLD and UNRELATED. Importantly, an item by diagnostic group interaction effect was observed, and post hoc analysis showed that patients with aMCI made a higher percentage of errors than controls in NEW items only. In conclusion, patients with aMCI had a particular difficulty in identifying the NEW items of the word-to-picture task as compared to the control participants, supporting the concept of a flexible and dynamic conceptual knowledge system, involving the update of semantic memories and the integration of new attributes in a constant transformation process, which is impaired in these patients.  相似文献   
56.
区域卫生规划与卫生资源配置   总被引:2,自引:0,他引:2  
区域卫生规划与卫生资源配置的关系密不可分,同时也是解决医疗保健供需平衡的重大举措和主要手段。首先提出了区域卫生规划的现实意义和基本理论,并分析了建立区域卫生规划对解决以上问题怎样产生积极的影响。  相似文献   
57.
Small unmanned aerial systems (sUAS), or drones, have become increasingly utilized for a myriad of applications in the vicinity of roadways and can offer a low-cost alternative to many labor-intensive data collection techniques, including infrastructure inspection, roadway marking data collection, and more. To collect much of this data with a desired degree of accuracy, sUAS must be flown near moving vehicles, pedestrians, and/or bicyclists. However, sUAS, and their operators, have the potential to be a distraction to drivers. Through a full-immersion driver simulator study and post-experiment questionnaire, this study furthered the current state-of-the-literature and investigated the potential for sUAS to be flown in the vicinity of roadways in the future as well as potential safety implications of those circumstances. Specifically, driver performance due to drone height and the presence of drone operators was evaluated. The results of the driving simulation study revealed that participants were more visually distracted in situations where the operators and drone were both present compared to the drone only scenarios. Furthermore, in 11% of all analyzed situations, drivers were critically visually-distracted as shown by a continuous glance of two seconds or more at the drone or operators. The post-experiment questionnaire revealed that approximately 30% of participants had seen a drone in flight near a roadway prior to this study. Ultimately, this research provides recommendations to policymakers for creating regulations on the use of sUAS in the vicinity of roadways.  相似文献   
58.
Missionaries from Europe came to India starting in the 15th century to preach the gospel. Their mission works have both intended and unintended consequences that affect people even today. Missionaries brought modern education to India and gave Western education to Dalits, leading to the social uplifting of Dalits, who were denied education by the oppressive caste system. Some missionaries also spoke against the social evils during their time. On the other hand, some missionaries’ work at times highlighted the Brahmanic religion as a pan-India religion which placed popular religions in a disadvantaged position. Furthermore, their work also helped the British colonial government to maintain control and become powerful. The translation work of the missionaries and the educational institutions helped the colonial government to strengthen its control over the local population. This article discusses the mission work of Robert de Nobili, Bartholomew Ziegenbalg, and William Carey and evaluates their mission works from Dalit and decolonial perspectives.  相似文献   
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