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71.
We provide an initial evaluation of the factor structure of the Impact of Event Scale-Revised (IES-R) when used with a volunteer firefighter and a similar community participant sample. A volunteer firefighter sample (n = 65) and a sample of similar community respondents (n = 103) completed a questionnaire study, including responses to the IES-R. The IES-R data from both groups were entered into a three-factor principal components analysis with direct oblimin rotation. We found further support for the validity of the IES-R when used with a community sample. However, our data suggested that when using the IES-R with a community sample, the choice between a two- and a three-factor model may depend on the composition of the participants. For volunteer firefighters, the factor-analytic structure of the IES-R appeared to be similar to that of the community sample, with more scatter in terms of item loadings. To our knowledge, there is no previous research considering the use of the IES-R with a strictly volunteer firefighter sample. In addition, despite adequate research on the factor-analytic structure of the original IES, little research has considered the factor-analytic structure of the more recent IES-R, even with community samples. 相似文献
72.
《International Journal of Clinical and Health Psychology》2014,14(2):154-160
Over the last few years, university policy in developed countries has placed too much emphasis on assessing publications on the basis of the impact factor. Any scientific material that has not been published in a journal indexed in the Journal Citation Reports is academically irrelevant. Hence, researchers strive hard to publish in such journals. Failure to achieve this means not having a successful career or receiving any academic recognition. A thorough analysis of the effects of this phenomenon on the researcher community leads to the conclusion that the overestimation of the impact factor is likely to cause disappointment among many researchers. Researchers only have two options: adopting a politically correct behavior, that is, following the “impact factor style of thinking”, or accepting the futility of their research regardless of its relevance. This is an example of the involvement of university policy habitus obsessed impact index. O policy impact index is accepted, or is doomed to academic ostracism, and exclusion from participation in all university policy. 相似文献
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长期以来,肿瘤学的几乎所有研究一直在关注肿瘤细胞本身,从哲学角度看这无疑是正确的。肿瘤细胞是肿瘤事件发生发展的内因。近年研究表明,肿瘤的外因,即肿瘤微环境中的非肿瘤细胞及其产物,对肿瘤的发生发展起着十分重要的作用。肿瘤微环境的外因,通过作用于内因选择了更具抵抗性的肿瘤细胞,促进了肿瘤的进展与转移。因此,重视肿瘤微环境的外因研究,对肿瘤治疗学将会开辟以外因为靶点干预的新思路。 相似文献
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Pseudo-guessing parameters are present in item response theory applications for many educational assessments. When sample size is not sufficiently large, the guessing parameters may be ignored from the analysis. This study examines the impact of ignoring pseudo-guessing parameters on measurement invariance analysis, specifically, on item difficulty, item discrimination, and mean and variance of ability distribution. Results show that when non-zero guessing parameters are ignored from the measurement invariance analysis, item discrimination estimates tend to decrease particularly for more difficult items, and item difficulty estimates decrease unless the items are highly discriminating and difficult. As the guessing parameter increases, the size of the decrease in item discrimination and difficulty tends to increase, and the estimated mean and variance of ability distribution tend to be inaccurate. When two groups have heterogeneous ability distributions, ignoring the guessing parameter affects the reference group and the focal group differently. Implications of result findings are discussed. 相似文献
78.
早期剥夺所致大鼠抑郁样行为与海马BDNF mRNA表达变化 总被引:1,自引:0,他引:1
为探讨早期剥夺对大鼠行为与海马脑源性神经营养因子(BDNF)mRNA表达的影响,将新生的SD大鼠随机分为正常对照组与早期剥夺组,早期剥夺组在出生后1~14d每天孤养4h。监测体重,在出生后36?64天进行液体消耗试验,每周一次。12w龄时,进行穿梭箱试验,酶联免疫法检测海马BDNF含量,原位杂交法观察海马BDNF mRNA的表达。早期剥夺组大鼠体重显著低于正常对照组(p0.01),糖水摄入量与糖水偏爱显著低于正常对照组(p0.05或p0.01)。穿梭箱试验中,早期剥夺组大鼠在训练时的穿梭反应次数显著少于正常对照组(p0.05),在测试时,两组大鼠的被动逃避行为、主动逃避行为与逃避错误次数无显著差异。早期剥夺组大鼠海马BDNF含量、CA1区和CA3区BDNF mRNA表达显著低于正常对照组(p=0.05或p0.05)。提示早期剥夺可导致大鼠生长减慢,表现出快感缺失的抑郁样行为,但未诱导成年大鼠表现出明显的习得性无助倾向,早期剥夺能下调成年大鼠海马BDNFmRNA的表达。 相似文献
79.
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
80.
Christof Schuster Dirk Lubbe 《The British journal of mathematical and statistical psychology》2020,73(1):164-169
Although a statistical model might fit well to a large proportion of the individuals of a random sample, some individuals might give ‘unusual’ responses that are not well explained by the hypothesized model. If individual responses are given as continuous response vectors, M-distances can be used to produce real valued indicators of how well an individual's response vector corresponds to a covariance structure implied by a psychometric model. In this note, we focus on the so-called one-factor model. Two M-distances, dsi and dri, which are sensitive to different aspects of the assumed factor model, have been proposed. While one of the M-distances, dri, has been derived based on Bartlett factor scores, in this note we show that the second M-distance, dsi, can be derived in an analogous fashion based on Thomson factor scores. 相似文献