期刊文献+
共找到16篇文章
< 1 >
每页显示 20 50 100
梨杂交后代童期和童程的研究 被引量:14
1
作者 崔艳波 张绍铃 +1 位作者 吴华清 沙守峰 《中国农学通报》 CSCD 北大核心 2011年第2期128-131,共4页
以2004年杂交的8个梨杂交组合后代492株实生树为试材,调查了其童程、始花节位数、节间长度和树干直径,探讨了童期和童程以及二者的关系,以期为杂交育种提供理论参考。结果表明:在调查的所有杂交组合中,到2010年为止有68.7%的杂种实生后... 以2004年杂交的8个梨杂交组合后代492株实生树为试材,调查了其童程、始花节位数、节间长度和树干直径,探讨了童期和童程以及二者的关系,以期为杂交育种提供理论参考。结果表明:在调查的所有杂交组合中,到2010年为止有68.7%的杂种实生后代结束童期,童期为3~5年,平均童程为214.26cm,2008年结束童期的平均童程为202.86cm,推断是结束童期的最小童程;节间长度与童程存在正相关性,相关系数为0.586,始花节位数和干径都与童程存在极显著的正相关性,相关系数分别为0.908**和0.886**;童期与童程存在极显著的正相关,在一定的范围内童程越低的实生树,童期越短,开花结果越早,而矮化的植株具有早结果的潜力。 展开更多
关键词 杂交后代 童期 童程
下载PDF
柑桔砧木实生苗的童期和童程研究 被引量:7
2
作者 张谷雄 陈建平 +1 位作者 邓光宙 王友存 《中国柑桔》 1990年第2期7-9,共3页
通过对15种柑桔砧木实生苗的童期和童程的调查研究和统计分析,认为童期的长短首先取决于遗传基础。童程与童期呈极显著正相关。节间短的实生苗童程也短,故节间长度可作为早实性早期选择的参数。童期越长的品种类型,结束童期的分枝级数越... 通过对15种柑桔砧木实生苗的童期和童程的调查研究和统计分析,认为童期的长短首先取决于遗传基础。童程与童期呈极显著正相关。节间短的实生苗童程也短,故节间长度可作为早实性早期选择的参数。童期越长的品种类型,结束童期的分枝级数越高,干周和冠径越大,树体也越高,首次始花点的分枝级数可作为实生苗结束童期的主要形态指标。高砧芽接实生苗可降低首次开花点分枝级数和缩短童程,从而缩短童期1.77~3.33年。 展开更多
关键词 柑桔 砧木 实生苗 童期 童程
下载PDF
主干环割对梨杂种后代童期、童程及相关指标的影响 被引量:7
3
作者 凌天亚 杨健 +5 位作者 王苏珂 王龙 薛华柏 马俊华 李疆 李秀根 《中国果树》 2015年第3期16-19 31,共5页
以2个3年生梨杂交组合玉露香×红酥脆和玉露香×满天红实生后代为试材,对其主干进行环割处理,研究环割对梨杂种后代叶片干物质积累、开花株率、单株成花数、童期和童程的影响。结果表明:环割能够增加叶片干物质含量,玉露香×... 以2个3年生梨杂交组合玉露香×红酥脆和玉露香×满天红实生后代为试材,对其主干进行环割处理,研究环割对梨杂种后代叶片干物质积累、开花株率、单株成花数、童期和童程的影响。结果表明:环割能够增加叶片干物质含量,玉露香×满天红实生后代环割处理6月19日和7月22日其叶片干物质含量显著高于对照,但玉露香×红酥脆实生后代环割处理叶片的干物质含量比与对照差异不显著;2个组合杂种后代环割后开花株率和成花总数、最多单株成花数均有显著提高,其童期缩短,但对童程的影响不显著。 展开更多
关键词 杂种后代 主干 环割 叶片干物质含量 开花株率 童程 童期
下载PDF
梨果实若干外观性状及童期的遗传学调查 被引量:2
4
作者 李先明 秦仲麒 +4 位作者 涂俊凡 杨夫臣 朱红艳 伍涛 邓海洲 《江西农业学报》 CAS 2016年第7期22-26,共5页
以梨16个组合的2086株杂种后代为试材,对各组合亲本及后代的果实果形指数、萼片的脱落与宿存、果皮色泽等外观性状及童期、童程进行了分析,研究其遗传倾向。结果表明:梨果实果形指数为由多基因控制的数量性状,表现为微效多基因的累加效... 以梨16个组合的2086株杂种后代为试材,对各组合亲本及后代的果实果形指数、萼片的脱落与宿存、果皮色泽等外观性状及童期、童程进行了分析,研究其遗传倾向。结果表明:梨果实果形指数为由多基因控制的数量性状,表现为微效多基因的累加效应,加性效应所占的比例较大,平均组合传递力为94.88%,平均变异系数为9.49%;果实萼片脱落以及果皮色泽在杂种后代分离广泛;杂种后代的童程平均为2.01 m,2011年各组合杂种后代的平均开花株率为5.34%,2012~2015年的分别为42.97%、60.40%、78.98%、84.42%。 展开更多
关键词 杂种 外观性状 童期 童程 遗传倾向
下载PDF
解放钟枇杷北引栽培试验初报
5
作者 郭春秋 邓学金 +2 位作者 彭友林 贵云 李运锋 《湖南农业科学》 1999年第2期32-33,共2页
通过对不同立地条件下解放钟枇杷的生长特性观察比较,提出了该品种从福建莆田引种至湖南常德栽培时育苗阶段必须注意的一些问题,并就已获得的原始数据进行分析,为枇杷北引栽培过程中缩短童期、提早结果提供了科学依据。
关键词 解放钟枇杷 驯化 引种 童程 枇杷
下载PDF
显象管中的残余气体
6
作者 吴冲若 诸玉华 陈章其 《电子器件》 CAS 1981年第3期49-70,共22页
近年来国内在显象管的材料和工艺上做了大量的工作,使国产显象管的质量普遍有所提高,但为了赶上和超过国外显象管生产的先进水平,有待于我们继续努力。当前,如何延长国产显象管的使用寿伞,仍然是一个重要的课题,影响显象管寿命的因素很... 近年来国内在显象管的材料和工艺上做了大量的工作,使国产显象管的质量普遍有所提高,但为了赶上和超过国外显象管生产的先进水平,有待于我们继续努力。当前,如何延长国产显象管的使用寿伞,仍然是一个重要的课题,影响显象管寿命的因素很多,由于显象管具有有效阴极面小,电压高等特点管内的残余气体是一个极为重要的因素,通过管内残余气体的研究,不但可以找出寿终的原因,探索延长寿命的途径,而且也为合理确定制管工艺,正确选用管内材料。提供了依据,可见分析显象管中的残余气体是一项十分重要,不容忽视的工作 本文主要介绍了研究显象管中残余气体的装置和方法,讨论了国产显象管的各个阶段中,管内残余气体的变化规律。 展开更多
关键词 残余气 童程 氨气 显象 离子 一匡 除气 氦气
下载PDF
广州市乡镇建材工业协会成立
7
作者 蔡禧 《广东建材》 1994年第4期23-23,共1页
广州市乡镇建材工业协会成立大会于1994年6月14日在广州市珠岛宾馆召开,省、市有关单位代表,会员单位代表约80余人出席了成立大会。 出席会议的会员单位代表听取了协会的筹备情况及协会章程(草案)的说明,审议通过了协会章程,经过民主协... 广州市乡镇建材工业协会成立大会于1994年6月14日在广州市珠岛宾馆召开,省、市有关单位代表,会员单位代表约80余人出席了成立大会。 出席会议的会员单位代表听取了协会的筹备情况及协会章程(草案)的说明,审议通过了协会章程,经过民主协商,充分酝酿,选举产生由34人组成的常务理事会,选举游汉铨同志为首届理事长,陈锦炎等9人为副理事长,周伟涛同志为秘书长,会议还聘请广州市石井水泥厂厂长李根同志为特别顾问。 展开更多
关键词 建材工业 广州市 乡镇 理事长 会员单位 常务理事会 章程 出席会议 政府工作职能 童程
下载PDF
Children's expectancy beliefs and subjective task values through two years of school-based program and associated links to physical education enjoyment and physical activity 被引量:2
8
作者 Arto Gr?stén 《Journal of Sport and Health Science》 SCIE 2016年第4期500-508,共9页
Purpose:The present study examined the patterns of children's expectancy beliefs and subjective task values through the Physical Activity as Civil Skill Program and associated links to physical education enjoyment a... Purpose:The present study examined the patterns of children's expectancy beliefs and subjective task values through the Physical Activity as Civil Skill Program and associated links to physical education enjoyment and total physical activity.Methods:The sample comprised 401 children aged 9–13 years from 3 small towns located in North-East Finland.All children received school-based activities across 2-year program from Grades 5 to 7.The present data were collected using questionnaires across 3 measurement phases during 2012–2014.Results:The levels of expectancy beliefs and subjective task values indicated to be relatively high and the development was stable through the program,especially in terms of expectancy beliefs,attainment value,and cost.In contrast,interest value and utility value decreased over the particular period of time.Boys believed they are physically more competent when compared to other students and valued physical education classes more important than girls.In addition,the higher the physical activity level the children reported,the higher the physical education enjoyment they perceived.Conclusion:The current program including actions to increase physical activity through manipulation of psychological and physical school environment modification indicated to be an effective strategy to prohibit declining levels of children's expectancy beliefs and task values. 展开更多
关键词 Exercise motivation Expectancy beliefs Expectancy-value theory Physical activity Physical education enjoyment Task values
下载PDF
Exercise and children's cognition:The role of exercise characteristics and a place for metacognition 被引量:12
9
作者 Phillip D.Tomporowski Bryan Mc Cullick +1 位作者 Daniel M.Pendleton Caterina Pesce 《Journal of Sport and Health Science》 SCIE 2015年第1期47-55,共9页
Definitive conclusions concerning the impact of exercise interventions on children's mental functioning are difficult to ascertain because of procedural differences among studies. A narrative review of studies was co... Definitive conclusions concerning the impact of exercise interventions on children's mental functioning are difficult to ascertain because of procedural differences among studies. A narrative review of studies was conducted to evaluate the role of two types of exercise interventions on children's cognition. Acute and chronic exercise interventions were classified as quantitative or qualitative on the basis of manipulations of task complexity and, by inference, mental engagement. Both types of interventions enhance aspects of children's cognition; however, their effects on metacognitive processes are unknown. The role of metacognitive processes and their regulation of children's behavior and academic performance are highlighted. 展开更多
关键词 Academic achievement Child development Executive function Intelligence Memory Mental engagement
下载PDF
Children witness a systematic research
10
作者 Li Yang 《International English Education Research》 2014年第6期13-15,共3页
in China, children witness has not been articled in three procedural laws, some scholar do not think that either children nor other person with no legal capacity should have witness qualification.in fact, although som... in China, children witness has not been articled in three procedural laws, some scholar do not think that either children nor other person with no legal capacity should have witness qualification.in fact, although some other countries do not admit the qualification of children witnesses under certain age,they do not take it as the factor to measure whether a witness has qualification or not.It is the judge who can decide whether a witness has qualification or not.Based on the these foreign counlries' s experience,we should not limit the qualification of children witnesses in the legislation. However, for the particularity of children's cognitive ability,we should embody this particularity when we judge children's testimony and protect children witnesses. 展开更多
关键词 Children witness witness qualification witness protection testimony scrutiny
下载PDF
The effects of a daily, 6-week exergaming curriculum on balance in fourth grade children 被引量:1
11
作者 Dwayne P.Sheehan Larry Katz 《Journal of Sport and Health Science》 SCIE 2013年第3期131-137,共7页
Balance is an essential component of movement and is critical in the ability to participate in physical activity. Developing an exergaming curriculum for schools has the potential to improve balance or postural stabil... Balance is an essential component of movement and is critical in the ability to participate in physical activity. Developing an exergaming curriculum for schools has the potential to improve balance or postural stability in children. In this study, a purposely-built exergaming center in an elementary school was used to test fourth grade students with a specially designed exergaming curriculum oriented toward improving postural stability. The program was implemented over a 6-week period, 34 min per day, 4-5 days per week. Two control groups were used: (1) a physical education (PE) class geared toward agility, balance, and coordination (ABC) improvement, and (2) a typical PE curriculum class. Exergaming students improved their postural stability significantly over a 6-week period compared to those in the typical PE class. Improvements in postural stability were also evident in the ABC class. Postural stability in the girls was better than the boys in all pre- and post-intervention tests. This study demonstrates that exergaming is a practical resource in the PE class to improve postural stability. 展开更多
关键词 Balance CHILDREN Elementary school Exergaming Fundamental movement skills
下载PDF
Children witness --a systematic research
12
作者 Li Yang 《International English Education Research》 2014年第7期40-42,共3页
In China, children witness has not been articled in three procedural laws, some scholar do not think that either children nor other person with no legal capacity should have witness qualification.In fact, although som... In China, children witness has not been articled in three procedural laws, some scholar do not think that either children nor other person with no legal capacity should have witness qualification.In fact, although some other countries do not admit the qualification of children witnesses under certain age, they do not take it as the factor to measure whether a witness has qualification or not. It is the judge who can decide whether a witness has qualification or not. Based on the these foreign countries's experience, we should not limit the qualification of children witnesses in the legislation. However, for the particularity of children's cognitive ability, we should embody this particularity when we judge children's testimony and protect children witnesses. 展开更多
关键词 Children witness witness qualification witness protection testimony scrutiny
下载PDF
The Positive Effects of Preschool Education in the Socialization and Learning of Children
13
作者 Valbona Keci 《Sociology Study》 2016年第2期140-145,共6页
The purpose of this study is to highlight the positive effects that the attendance of preschool education has on the soclanzauon and on the learning level of children. They are related with the kind of preschool educa... The purpose of this study is to highlight the positive effects that the attendance of preschool education has on the soclanzauon and on the learning level of children. They are related with the kind of preschool education that the child attends, with the area where the child lives, with the education level of the parents, with the way how the learning process is realized in the kindergarten. Five hundred (500) first graders of the city of Durres are chosen. Parents and teachers will be part of the study only after taking the consent from RIE (Regional Institute of Education). The completed surveys from the parents will create us an idea of the situation how they experience this and what their expectations regarding their children are. Surveillance will be another important method that will be used to give the conclusion of this study. Children will be watched during spontaneous and one-hour made situations. Statistical data from the two groups of children and parents tests will help us prove how visible the positive effects of attending the preschool education on the performance children show during first grade are. At the end of the study, it will be asked to prove that the attendance of preschool education in specialized institutions has positive effects on the development children show in the first grade in the two targets which we have chosen to study. 展开更多
关键词 Preschool education SOCIALIZATION LEARNING KINDERGARTEN GAME rural-urban
下载PDF
A Study of Application of Games in Children English Teaching Taking Children English Class in Education First Training School for Example
14
作者 REN Lu-lu 《Sino-US English Teaching》 2016年第9期704-709,共6页
As a teaching aid, games are vital to facilitate every part in learning process. They are easy to arouse learners' attention and are accessible to achieve teaching objectives compared with traditional teaching. The a... As a teaching aid, games are vital to facilitate every part in learning process. They are easy to arouse learners' attention and are accessible to achieve teaching objectives compared with traditional teaching. The author did two-month classroom observations in Education First Training School in Ningbo. This paper discusses and shares useful and effective games provided in English class. 展开更多
关键词 GAMES CHILDREN English teaching Education First Training School
下载PDF
The Problems and Countermeasures about Preschool Art Curriculum
15
作者 Li Yadong 《International Journal of Technology Management》 2015年第7期103-105,共3页
With the continuous reforms of education and development of kindergartens, preschool education is valued more, especially enhancing the standard of teachers' s artistic ability. Preschool education not only plays a c... With the continuous reforms of education and development of kindergartens, preschool education is valued more, especially enhancing the standard of teachers' s artistic ability. Preschool education not only plays a crucial role in the development of children' s mind and body, but can promote the development of children' s IQ and learning potential, cultivating children' s overall qualities comprehensively. 展开更多
关键词 Preschool Education Art Curriculum Problems COUNTERMEASURES
下载PDF
Association between SMN2 methylation and disease severity in Chinese children with spinal muscular atrophy 被引量:4
16
作者 Yan-yan CAO Yu-jin QU +5 位作者 Sheng-xi HE Yan LI Jin-li BAI Yu-wei JIN Hong WANG Fang SONG 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2016年第1期76-82,共7页
The homozygous loss of the survival motor neuron 1 (SMN1) gene is the primary cause of spinal muscular atrophy (SMA), a neuromuscular degenerative disease. A genetically similar gene, SMN2, which is not functional... The homozygous loss of the survival motor neuron 1 (SMN1) gene is the primary cause of spinal muscular atrophy (SMA), a neuromuscular degenerative disease. A genetically similar gene, SMN2, which is not functionally equivalent in all SMA patients, modifies the clinical SMA phenotypes. We analyzed the methylation levels of 4 CpG islands (CGIs) in SMN2 in 35 Chinese children with SMA by MassARRAY. We found that three CpG units located in CGI 1 (nucleotides (nt) -871, -735) and CGI 4 (nt +999) are significantly hypomethylated in SMA type III compared with type I or II children after receiving Bonferroni correction. In addition to the differentially methylated CpG unit of nt -871, the methylation level of the nt -290/-288/-285 unit was negatively correlated with the expression of SMN2 full-length transcripts (SMN2-fl). In addition, the methylation level at nt +938 was inversely proportional to the ratio of SMN2-fl and lacking exon 7 transcripts (SMN2-A7, fl/A7), and was not associated with the SMN2 transcript levels. Thus, we can conclude that SMN2 methylation may regulate the SMA disease phenotype by modulating its transcription. 展开更多
关键词 CpG island METHYLATION Survival motor neuron 2 (SMN2) Spinal muscular atrophy
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部