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71.
Yun-lei Cao Zhao-feng Zhang Jian Wang Mao-hua Miao Jian-hua Xu Yue-ping Shen Ai-min Chen Jing Du Wei Yuan 《Journal of Zhejiang University. Science. B》2016,17(3):218-224
Recurrent pregnancy loss (RPL) is a condition with complex etiologies, to which both genetic and environmental factors may contribute. During the last decade, studies indicated that the expression patterns of the prokineticin receptor (PKR1 and PKR2) are closely related to early pregnancy. However, there are few studies on the role of PKR1 and PKR2 in RPL. In this study, we purpose to investigate the association between polymorphisms of the prokineticin receptor (PKR1 rs4627609 and PKR2 rs6053283) and RPL on a group of 93 RPL cases and 169 healthy controls. Genotyping of the single nucleotide polymorphisms (SNPs) was performed using a Sequenom MassARRAY iPLEX system. The results revealed a significant association between PKR2 rs6053283 polymorphism and RPL (P=0.003), whereas no association was observed between PKR1 rs4627609 polymorphism and RPL (P=0.929) in the Chinese Han population. 相似文献
72.
本文较详细地研究了由几种微细粉配制而成的浆体的流变性能,同时通过加入不同减水剂,研究了减水剂对浆体流变性能的影响,实验表明,自流浇注料的基质——“粉体—水系统”基本上呈宾汉姆流型,而适量的减水剂的加入会明显影响它的流变性质,对于减水剂的作用机理及微细粉浆体的结构与其流变性质的关系,本文亦作了一定程度的探讨。 相似文献
73.
The Consistency and Concomitants of Inhibition: Some of the Children, All of the Time 总被引:6,自引:1,他引:6
Kenneth H. Rubin Paul D. Hastings Shannon L. Stewart Heather A. Henderson Xinyin Chen 《Child development》1997,68(3):467-483
Toddlers displaying extremely inhibited behavior may be at risk for becoming socially withdrawn. However, behavioral inhibition may be a multifaceted characteristic, and its concurrent relation to toddler wariness with peers has not been examined. In this study, 108 toddlers (54 females) and their mothers were observed in novel situations involving unfamiliar settings, adults, and peers. Vagal tone, temperament, separation-reunion behavior, and maternal oversolicitousness also were assessed. There was little consistency of inhibited behavior across the 3 situations. Consistently inhibited toddlers had fearful temperaments, showed distress following maternal separation, and had mothers who were warm and controlling but unresponsive to children's cues during interaction. Toddlers with highly fearful temperaments and highly oversolicitous mothers were the most inhibited across contexts. 相似文献
74.
The purpose of this study was to determine if there is a relationship between learner personality types and perceived satisfaction when using Web-based instruction for mandatory and self-regulated continuing professional development. Two hundred and four real estate practitioners who participated in a Web-based professional development course completed the Millon Index of Personality Styles (MIPS) instrument and a survey to compare personality type and satisfaction. No relationship was found between personality types and satisfaction when using Web-based instruction. The majority (97%) of participants were satisfied with the course regardless of their personality characteristics. 相似文献
75.
杜新立 《石家庄铁路职业技术学院学报》2006,5(Z1):10-13
介绍上海市磁悬浮轨道交通线工程磁悬浮轨道梁模板的制作与工艺控制方法,探讨高精度模板加工工艺控制. 相似文献
76.
杜爱明 《中国教育技术装备》2001,(2):6-9
美国教育传播与技术协会1994年推出的教育技术的新定义是:“教育技术学是关于学习过程和学习资源的设计、开发、利用、管理和评价的理论与实践。”教育技术充分运用了各种信息技术。随着科学技术的进步,应用于教育和教学过程的信息技术也在不断地发展,核心媒体经历了无线电技术一录像技术一计算机(网络)技术3个发展阶段。当前,正在经历从音像媒体向计算机(网络)为核心媒体的阶段发展,进 相似文献
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79.
ABSTRACT Cities in the United States and across the world have experienced gentrification at the same time as school choice policies have become more popular. This research examines the relationship between gentrification and charter schooling, seeking to understand how together they affect demographic composition of schools across Washington, DC. This study uses geographic information systems (GIS) mapping and statistical techniques to show that gentrified neighborhoods are more likely to have charter schools. Additionally, the demographic compositions of charter schools and traditional public schools differ depending on the gentrification classification of the census tract in which the schools are located. While a handful of diverse charter schools exist in gentrified neighborhoods and some diverse public schools exist in traditionally affluent neighborhoods, schools in Washington, DC remain racially and economically isolated overall. 相似文献
80.