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61.
采用荧光PCR法对199例晚期非小细胞肺癌(NSCLC )组织进行表皮生长因子受体(EGFR )基因突变检测,分析EGFR基因突变的分布特征及其与临床病理特征的相关性。结果显示56例(28.1%)存在EGFR基因突变,其中27例(13.6%)为外显子19突变,25例(12.6%)为外显子21突变,2例为外显子18突变,1例外显子20突变,1例外显子18和20的共突变。另外,除广东及安徽省铜陵市外,辽宁地区NSCLC患者EGFR基因突变率及主要突变类型与其他地区相符,常见于外显子19、21突变,其中腺癌、不吸烟患者突变率更高,更适宜EGFR-TKI靶向治疗。  相似文献   
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63.
选题是计算机化自适应测验(CAT)测试过程的关键环节,选题策略的目标是要达到较高的测量精度,同时也实现试题曝光率控制及其他测验目标的实现.本文根据选题策略的基本原理和衍生发展,将众多CAT选题策略分为五大选题策略系列:Fisher函数系列、K-LI函数系列、α分层系列、贝叶斯系列、b匹配系列;并根据测验目标(测验精度、试题曝光率控制、内容平衡、多条件约束)对这些选题策略进行了细分,并对CAT选题策略的选择思路进行归纳.  相似文献   
64.
Limited research has been conducted on dispositional mindfulness, posttraumatic stress disorder (PTSD) symptoms and academic burnout in Chinese adolescents following a tornado. The present study investigated the ways in which dispositional mindfulness is related to PTSD symptoms and academic burnout in Chinese adolescents following a tornado by considering the role of regulatory emotional self-efficacy. A total of 431 Chinese adolescents (mean age: 14.75 years) who had experienced a severe tornado 9 months prior to this study were recruited for this study. The results indicated that our model fit the data well [χ2/df = 2.774, CFI = 0.952, TLI = 0.934, RMSEA (90% CI) = 0.064 (0.051–0.077)], and revealed that regulatory emotional self-efficacy partially mediates the relationships between dispositional mindfulness and PTSD symptoms and academic burnout, respectively. The clinical implications and limitations of our research, and recommendations for future research, are discussed in this paper.  相似文献   
65.
过去的研究发现,在经历挫折后,相比于不听音乐,听积极音乐能提升人们的希望感。然而,研究者并不清楚积极音乐和消极音乐在提升希望感上是否存在差异,也不清楚这种差异是否由于两种音乐在诱发的积极情绪或消极情绪的差异造成的。文章通过三个实验来考察这些问题。实验一发现,在无挫折的情况下,积极音乐相比消极音乐诱发了更强的希望感。实验二发现,这种效应同样存在于人们回忆挫折之后,并且是积极情绪在其中起中介作用。实验三则通过设置控制组进一步发现,这种效应是由积极音乐对希望感的提升作用和消极音乐对希望感的降低作用共同引起的。文末讨论了该发现的意义。  相似文献   
66.
We discuss measuring and detecting influential observations and outliers in the context of exponential family random graph (ERG) models for social networks. We focus on the level of the nodes of the network and consider those nodes whose removal would result in changes to the model as extreme or “central” with respect to the structural features that “matter”. We construe removal in terms of two case-deletion strategies: the tie-variables of an actor are assumed to be unobserved, or the node is removed resulting in the induced subgraph. We define the difference in inferred model resulting from case deletion from the perspective of information theory and difference in estimates, in both the natural and mean-value parameterisation, representing varying degrees of approximation. We arrive at several measures of influence and propose the use of two that do not require refitting of the model and lend themselves to routine application in the ERGM fitting procedure. MCMC p values are obtained for testing how extreme each node is with respect to the network structure. The influence measures are applied to two well-known data sets to illustrate the information they provide. From a network perspective, the proposed statistics offer an indication of which actors are most distinctive in the network structure, in terms of not abiding by the structural norms present across other actors.  相似文献   
67.
This study investigated 5-year-old Mandarin-speaking children’s comprehension of wh-questions, universal statements and free choice inferences. Previous research has found that Mandarin-speaking children assign a universal interpretation to sentences with a wh-word (e.g., shei ‘who’) followed by the adverbial quantifier dou ‘all’ (Zhou in Appl Psycholinguist 36:411–435, 2013). Children also compute free choice inferences in sentences that contain a modal verb in addition to a wh-word and dou (Zhou, in: Nakayama, Su, Huang (eds.) Studies in Chinese and Japanese language acquisition: in honour of Stephen Crain. John Benjamins Publishing Company, Amsterdam, pp 223–235, 2017). The present study used a Question-Statement Task to assess children’s interpretation of sentences containing shei + dou, both with and without the modal verb beiyunxu ‘was allowed to’, as well as the contrast between sentences with shei + dou, which are statements for adults, versus ones with dou + shei, which are wh-questions for adults. The 5-year-old Mandarin-speaking child participants exhibited adult-like linguistic knowledge of the semantics and pragmatics of wh-words, the adverbial quantifier dou, and the deontic modal verb beiyunxu.  相似文献   
68.
The present study used a Truth Value Judgment Task to investigate whether changes in sentence structure lead to corresponding changes in the assignment of scope relations by Mandarin-speaking children and adults. In one condition, participants were presented with ordinary negative sentences containing disjunction; this condition was designed to verify the existing claim that disjunction is a positive polarity item for adult speakers of Mandarin, but not for child speakers. In a second condition, participants were presented with negative sentences where the disjunction phrase was preposed from object position; this condition was designed to examine the extent to which changes in sentence structure can result in changes in scope assignments to negated disjunctions. The results indicate that the preposed disjunction phrase undergoes reconstruction for children, whereas reconstruction is blocked for adults. This finding also suggests that Mandarin-speaking children and adults exhibit different scope preferences for negated disjunctions, regardless of where the disjunction phrase appears in the surface syntax.  相似文献   
69.
The present studies sought to investigate the mapping relations between language and cognition by focusing on how Mandarin-speaking children acquire the mapping between their conceptual knowledge of possession and their linguistic expressions of possession. Two experiments were conducted. Experiment 1 used a comprehension task to explore whether young children are able to map their knowledge of possessive constructions onto their interpretation of possessive relations. Experiment 2 employed a production task to examine whether they are able to map their knowledge of possessive relations onto their linguistic expressions of possession. The findings were that 4-year-olds exhibited correct comprehension and production of possessive DE constructions, indicating that by age 4, Mandarin-speaking children have already established the mapping between their conceptual knowledge of possession and their linguistic expressions of possession. By contrast, 3-year-olds exhibited response patterns that suggest a developmental stage where they use noun–noun compounds to represent possessive relations before they map possessive relations onto possessive constructions.  相似文献   
70.
马泽威  全鹏 《心理科学》2015,(2):379-382
考察抑郁在青少年核心自我评价与自杀意念间的中介作用。对502名高中生进行量表测评。通过偏差校正的Bootstrap法和有先验信息的MCMC法求出中介效应值的95%置信区间分别为[-.030,-.011]和[-.024,-.014],提示抑郁的中介效应显著。效应量k2、R2med分别为.124、.104,偏差校正的Bootstrap法抽样5000次后,构建的效应量的95%置信区间分别为[.070,.178]、[.063,.156],两种指标共同验证效应量为中等。研究结果说明抑郁在核心自我评价与自杀意念间起部分中介作用,效应量中等。  相似文献   
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