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71.
Betty Vohr Lucille St Pierre Deborah Topol Julie Jodoin-Krauzyk Jessica Bloome Richard Tucker 《Early human development》2010,86(4):255-260
Objectives
To identify important maternal and child factors associated with development of vocabulary in a cohort of children with and without permanent hearing loss (HL).Methods
Children with HL and typical hearing were enrolled after the newborn hearing screen. Mother-child dyads were evaluated at 18-24 months of age. Mothers completed the MacArthur-Bates Communicative Development Inventory (MCDI). Maternal communicative effectiveness was scored using the Parent/Caregiver Involvement Scale (PCIS) from a 10 min play session. Correlations and regression models were run to identify the important predictors of number of child words produced.Results
Results from 40 children with typical hearing and 31 children with HL are reported. Words produced (134 ± 135 vs. 71 ± 112) and words produced percentile (33 ± 42 vs. 17 ± 23) scores on the MCDI were significantly higher for children with hearing compared to children with HL. Greater maternal stress was associated with decreased verbal involvement, positive regard, availability, and enjoyment. Regression analysis revealed HL, stay in a Neonatal Intensive Care Unit (NICU), and maternal stress were associated with fewer words produced whereas more optimal maternal atmosphere and quality of control and directiveness were associated with more words produced.Conclusions
Maternal communicative behaviors, maternal stress, child HL, and child stay in the NICU were all associated with number of words produced at 18-24 months. 相似文献72.
Time Course of Processes Underlying Picture and Word Evaluation: An Event-Related Potential Approach
Summary: A substantial body of research suggests that the cognitive mechanisms for picture and word processes are functionally and
anatomically distinct. In spite of significant advancements in the understanding of pictures and words, the electrophysiological
activities mediating these processes are not well known. To address this issue, we examined event-related brain potentials
(ERPs) to pictures and their printed names in a modified dual-target oddball task. ERPs were recorded while participants classified
schematic pictures and their corresponding names into target and nontarget categories. Results showed that pictures and words
were associated with electrophysiological responses that differed temporally and topographically. In comparison to words,
P300s to pictures were characterized by shorter latency and larger amplitude at parietal electrodes. In contrast, words produced
greater P200 amplitude at frontal areas. The results are consistent with the view that categorization of pictures is faster
than words. Findings are discussed in relation to stimulus evaluation and the time course for picture and word classification. 相似文献
73.
图像存档与传输系统(picture archiving and communication system,PAcs)为现代医学影像学提供了全新的数字化影像信息平台,同时也为实施医学影像实践性教学提供了先进的手段。基于PACS的早期临床实践,不仅丰富了医学生的医学影像学知识,还加深了医学生对相关临床知识的了解。通过学生亲身经历和早期临床实践,可激发医学生主动学习兴趣,培养医学生初步临床思维能力。基于PACS的早期临床实践教学模式,对提高医学生临床实践能力具有重要的教学和实用价值。 相似文献
74.
Emilia Horjales-Araujo Ditte Demontis Ellen Kielland Lund Lene Vase Nanna Brix Finnerup Anders D. Børglum Troels Staehelin Jensen Peter Svensson 《Pain》2013
The perception of pain is determined by a combination of genetic, neurobiological, cultural, and emotional factors. Recent studies have demonstrated an association between specific genotypes and pain perception. Particular focus has been given to the triallelic polymorphism in the promoter region of the serotonin transporter gene in relation to pain perception. The aim of this study was to investigate whether the modulatory effect of emotions mediated by visual stimuli on muscular pain perception is genotype dependent. A total of 150 healthy subjects were selected on the basis of their polymorphism in the serotonin transporter gene. First, visual conditioning was performed with positive, negative, and neutral pictures from the International Affective Picture System, and the unpleasantness/pleasantness of the pictures was rated. Second, visual conditioning stimuli were presented while experimental jaw muscle pain was evoked by injection of hypertonic saline into the masseter muscle, and participants continuously rated pain intensity on an electronic visual analogue scale. The pictures induced similar changes in emotions across the 3 genotype groups, and hypertonic saline evoked moderate pain levels in all participants. However, in participants with a high expression of the serotonin transporter protein, conditioning with negative pictures increased pain intensity and positive pictures decreased pain intensity when compared with neutral pictures. In contrast, there were no significant effects of the pictures on pain perception in participants with either intermediate or low expression of the protein. These results suggest that polymorphisms in the serotonin transporter gene play an important role in emotions modulation of muscle pain. 相似文献
75.
The design and development of a physician-oriented PACS for the enhancement of e-hospital facilities
Recent advancements in modern medical diagnoses have required a huge increase of the use of equipment such as CT and ultrasound machines. Correspondingly, the storage and dissemination of these medical images have become an important issue to medical professionals. Unfortunately, management of these images has traditionally been slow and cumbersome. With the prevalence of the personal computer, however, along with increased network bandwidth, it is now possible to handle this information electronically as well as wirelessly. The Picture Archiving and Communication System (PACS) is at the forefront of this revolution. Yet, commercially available PACS software is generally prohibitively expensive for hospitals with limited financial resources. A dilemma among many hospitals is deciding how to acquire and implement the proper PACS system without unduly affecting the budget. In this paper, a full function, efficient, and economical PACS system is presented as a viable, non-compromising option for many small and medium-sized hospitals. This system, designed and developed mainly by the physicians and technicians of Puli Christian Hospital (PCH), with the assistance from academia, allows for customization to fit the needs of individual hospitals. This system can be used as the foundation of a hospital's health information infrastructure and to enhance e-hospital service. 相似文献
76.
Recently studied ‹old’ stimuli lead to larger frontal and parietal ERP responses than ‹new’ stimuli. The present experiment
investigated the neuromagnetic correlates (MEG) of this ‹old-new’ effect and its modulation by emotional stimulus content.
Highly arousing pleasant, highly arousing unpleasant and un-arousing neutral photographs were presented to the participants
with the instruction to memorize them. They were later re-presented together with new photographs in an old-new decision task.
In line with previous ERP studies, a long-lasting old-new effect (350–700 ms) was found. Independently, an emotion effect
also occurred, as reflected in a, particularly left temporal, activity increase for emotional pictures between 450 and 580 ms.
Moreover, only for the pleasant pictures did the early part of the old-new effect, which is thought to reflect familiarity
based recognition processes, interact with picture content: The old-new effect for pleasant pictures in frontal regions was
larger than the one for neutral or unpleasant pictures between 350 and 450 ms. In parallel, subjects’ responses were accelerated
towards and biased in favour of classifying pleasant pictures as old. However, when false alarm rate was taken into account,
there was no significant effect of emotional content on recognition accuracy. In sum, this MEG study demonstrates an effect
of particularly pleasant emotional content on recognition memory which may be mediated by a familiarity based process. 相似文献
77.
Electrophysiological studies of human visual perception typically involve averaging across trials distributed over time during an experimental session. Using an oscillatory presentation, in which affective or neutral pictures were presented for 6 s, flickering on and off at a rate of 10 Hz, the present study examined single trials of steady-state visual evoked potentials. Moving window averaging and subsequent Fourier analysis at the stimulation frequency yielded spectral amplitude measures of electrocortical activity. Cronbach's alpha reached values >.79, across electrodes. Single-trial electrocortical activation was significantly related to the size of the skin conductance response recorded during affective picture viewing. These results suggest that individual trials of steady-state potentials may yield reliable indices of electrocortical activity in visual cortex and that amplitude modulation of these indices varies with emotional engagement. 相似文献
78.
目的开发一种基于PACS的独立的教学系统,便于不同层次学生方便地学习各系统疾病的诊断与鉴别诊断。方法使用放射科信息系统(RIS)服务器作为系统服务器,总体采用B/S架构,Microsoft SQL 2005作为数据库,以ASP.NET为基本开发技术。使用JavaScript+DOM(文档对象模型)实现客户端的人机对话。软件构建完毕后,根据不同学习对象输入教学大纲、知识点和鉴别诊断知识点,并将PACS中的教学病例与知识点相关联。结果系统成功建立,主要包括软件架构和教学内容两大部分。授权用户登录后可进入"学习应用"界面,包含"学习中心"和"在线测试"。学习中心包括:教学大纲、知识点(含临床、病理、流行病学、影像学等内容)、鉴别诊断要点、PACS中相关病例链接。在线测试则包含不同难度的题库,系统自动评判对错。管理员拥有"数据维护"和"系统管理"两大权限,可对教学相关的目录、大纲、教学资源、试题和试卷进行维护,也可管理用户身份和权限。结论成功地建立了一种基于PACS的独立教学系统,能满足不同层次学生的需求,有助于提高医学影像学教学水平。 相似文献
79.
Ganz JB Davis JL Lund EM Goodwyn FD Simpson RL 《Research in developmental disabilities》2012,33(2):406-418
The Picture Exchange Communication System (PECS) is a widely used picture/icon aided augmentative communication system designed for learners with autism and other developmental disorders. This meta-analysis analyzes the extant empirical literature for PECS relative to targeted (functional communication) and non-targeted concomitant outcomes (behavior, social skills, and speech) for learners with autism, learners with autism and intellectual disabilities and those with autism and multiple disabilities. Effect size analyses were done using the Improvement Rate Difference method, an advanced metric. Effect sizes were independently analyzed for targeted and non-targeted outcomes, student age, learner disability, and number of phases in the PECS protocol acquired by learners. Results supported the judgment that PECS is a promising intervention method. Analysis also revealed that functional communication outcomes associated with the PECS protocol were most impacted, that preschool children and those with autism generally showed the strongest training effects, and that in general students who advanced through the most PECS protocol phases had the best outcomes. 相似文献
80.
Coppens KM Tellings A van der Veld W Schreuder R Verhoeven L 《Research in developmental disabilities》2012,33(1):119-128
In the present study we examined the effect of hearing status on reading vocabulary development. More specifically, we examined the change of lexical competence in children with hearing loss over grade 4-7 and the predictors of this change. Therefore, we used a multi-factor longitudinal design with multiple outcomes, measuring the reading vocabulary knowledge in children with hearing loss from grades 4 and 5, and of children without hearing loss from grade 4, for 3 years with two word tasks: a lexical decision task and a use decision task. With these tasks we measured word form recognition and (in)correct usage recognition, respectively. A GLM repeated measures procedure indicated that scores and growth rates on the two tasks were affected by hearing status. Moreover, with structural equation modeling we observed that the development of lexical competence in children with hearing loss is stable over time, and a child's lexical competence can be explained best by his or her lexical competence assessed on a previous measurement occasion. If you look back, differences in lexical competence among children with hearing loss stay unfortunately the same. Educational placement, use of sign language at home, intelligence, use of hearing devices, and onset of deafness can account for the differences among children with hearing loss. 相似文献