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单搭接接头胶层间隙对强度和应力的影响 被引量:12
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作者 余海洲 游敏 +1 位作者 郑小玲 付建科 《机械强度》 EI CAS CSCD 北大核心 2006年第5期775-779,共5页
研究单搭接接头胶缝中预留间隙对接头拉剪强度和应力分布的影响。结果表明,随着间隙长度的增加,接头的承载能力趋于减小,但接头的实际剪切强度却持续上升;当间隙长度继续增加时,接头的实际强度趋于下降。研究中还发现间隙所处的位置对... 研究单搭接接头胶缝中预留间隙对接头拉剪强度和应力分布的影响。结果表明,随着间隙长度的增加,接头的承载能力趋于减小,但接头的实际剪切强度却持续上升;当间隙长度继续增加时,接头的实际强度趋于下降。研究中还发现间隙所处的位置对接头的抗剪强度有较大的影响,胶层端部预留间隙使接头的承载能力和实际强度均显著下降。有限元数值分析结果表明,间隙长度超过某特定值后胶层中的应力集中程度会急剧上升,间隙位于端部时胶层中的应力集中程度明显高于位于中部的场合。 展开更多
关键词 间隙 单搭接接头 实际强度 应力集中 有限元法
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间隙对单搭接胶接接头强度和应力的影响 被引量:4
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作者 余海洲 游敏 +1 位作者 曹平 杨春梅 《三峡大学学报(自然科学版)》 CAS 2004年第1期41-43,共3页
研究了搭接长度为12.5 mm的单搭接接头搭接区域预留间隙对搭接强度和应力的影响.结果表明,间隙的位置对搭接强度有较大的影响.与连续胶层相比,胶层中部一定宽度的间隙虽然使名义强度降低,但对于提高单搭接接头的实际强度有明显的作用,... 研究了搭接长度为12.5 mm的单搭接接头搭接区域预留间隙对搭接强度和应力的影响.结果表明,间隙的位置对搭接强度有较大的影响.与连续胶层相比,胶层中部一定宽度的间隙虽然使名义强度降低,但对于提高单搭接接头的实际强度有明显的作用,剪切强度最大值可比连续胶层接头增大约60%,而胶层端部预留间隙却使名义强度和实际强度均显著降低.对两种接头进行了有限元的数值分析,指出最大应力仍然处于胶瘤端部附近,间隙位置对应力的峰值有较大的影响. 展开更多
关键词 有间隙胶缝 单搭接接头 强度 应力 有限元法
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种分分解槽母液置换降固含退槽法的实践
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作者 吴振国 《大众科技》 2023年第6期48-51,共4页
文章介绍了种分分解槽计划性清理对氧化铝生产的重要性,系统分析了种分分解槽传统退槽方法的缺点和弊端,创新提出了种分分解槽母液置换降固含退槽法。种分分解槽母液置换降固含退槽法,通过降低分解料浆固含和粘度,能够克服有机物引起分... 文章介绍了种分分解槽计划性清理对氧化铝生产的重要性,系统分析了种分分解槽传统退槽方法的缺点和弊端,创新提出了种分分解槽母液置换降固含退槽法。种分分解槽母液置换降固含退槽法,通过降低分解料浆固含和粘度,能够克服有机物引起分解料浆物理性质恶化的问题,显著提高种分分解槽退槽效率、降低作业人员操作安全风险和设备事故风险,解决了传统退槽方法存在的弊端问题,在生产实践中取得良好经济效益和其他效果,对降低氧化铝生产成本具有重要作用。 展开更多
关键词 种分分解槽 退槽 固含 母液 搅拌 电耗
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胶层中间隙长度及位置对接头剪切强度的影响 被引量:2
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作者 余海洲 游敏 郑小玲 《粘接》 CAS 2004年第3期13-15,19,共4页
研究了在单搭接接头上、胶缝中预留的不同长度间隙对接头剪切强度和剪切应力分布的影响。结果表明 ,随着间隙长度的增加 ,接头的承载能力趋于减小 ,但接头的实际剪切强度却持续上升 ,当间隙长度再继续增加时 ,接头的实际强度趋于下降。... 研究了在单搭接接头上、胶缝中预留的不同长度间隙对接头剪切强度和剪切应力分布的影响。结果表明 ,随着间隙长度的增加 ,接头的承载能力趋于减小 ,但接头的实际剪切强度却持续上升 ,当间隙长度再继续增加时 ,接头的实际强度趋于下降。研究中还发现间隙所处的位置对接头的剪切强度有较大的影响 ,胶层端部预留间隙使接头的承载能力和实际强度均显著下降。有限元数值分析的结果表明 ,间隙长度超过某特定值后 ,胶层中的应力集中系数会急剧上升 ,间隙位于端部时胶层中的应力集中程度明显高于位于中部处。 展开更多
关键词 胶层 有限元分析 接头 剪切强度 胶瘤 承载能力
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有间隙胶接劈裂接头应力分布的数值模拟 被引量:1
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作者 游敏 严沾谋 +1 位作者 张明松 余海洲 《中国机械工程》 EI CAS CSCD 北大核心 2007年第1期101-104,共4页
建立了有间隙胶接劈裂接头的有限元模型,并运用弹塑性有限元法,研究了间隙位置和长度对劈裂接头胶层中部应力分布的影响。研究结果表明:合理的间隙不仅对劈裂接头的应力峰值和接头的承载能力无明显影响,而且有利于提高接头的胶接质量;... 建立了有间隙胶接劈裂接头的有限元模型,并运用弹塑性有限元法,研究了间隙位置和长度对劈裂接头胶层中部应力分布的影响。研究结果表明:合理的间隙不仅对劈裂接头的应力峰值和接头的承载能力无明显影响,而且有利于提高接头的胶接质量;间隙的中心位置对接头的应力峰值影响显著,而间隙长度对接头的应力峰值无明显影响;当接头末端无胶层时,因应力峰值显著增大,可能导致接头的名义强度降低。 展开更多
关键词 间隙 劈裂接头 有限元法 应力分布 名义强度
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间隙长度与间隙位置对单搭接接头强度的影响
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作者 严永林 余海洲 《粘接》 CAS 2006年第3期15-17,26,共4页
研究了间隙长度和间隙位置对不同单搭接接头强度的影响。结果表明,随着间隙长度的增加,接头的承载能力趋于下降,但在适当的条件下,间隙连接接头并没有大幅度地减小其强度。研究中发现间隙所处的位置对接头的拉剪强度有较大的影响,间隙... 研究了间隙长度和间隙位置对不同单搭接接头强度的影响。结果表明,随着间隙长度的增加,接头的承载能力趋于下降,但在适当的条件下,间隙连接接头并没有大幅度地减小其强度。研究中发现间隙所处的位置对接头的拉剪强度有较大的影响,间隙位置对接头实际剪切强度的影响大于间隙长度的影响。文中还论述了同一长度间隙位于不同位置时对强度的影响。 展开更多
关键词 间隙 单搭接接头 剪切强度
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单搭接接头断续胶层中应力分布的数值分析 被引量:8
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作者 孙德新 游敏 廖湘辉 《三峡大学学报(自然科学版)》 CAS 2003年第6期541-544,共4页
在分析现有的单搭接接头胶层中有集中间隙的有限元模型的基础上,提出了用平面应力随厚度变化的模型取代平面应变模型思路,对比了连续胶层与胶层中有3个断续间隙时搭接部位上剪切应力分布情况.结果表明:与连续胶层的单搭接接头相比,有3... 在分析现有的单搭接接头胶层中有集中间隙的有限元模型的基础上,提出了用平面应力随厚度变化的模型取代平面应变模型思路,对比了连续胶层与胶层中有3个断续间隙时搭接部位上剪切应力分布情况.结果表明:与连续胶层的单搭接接头相比,有3个断续间隙的接头剪切应力分布模型大致相同,应力的峰值增加约10%,断续胶层仍承受了部分工作载荷. 展开更多
关键词 单搭接接头 断续胶层 有限元 剪切应力 胶粘剂
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产品设计的符号隐喻修辞方法研究 被引量:32
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作者 宋文娟 杨永发 王坤茜 《包装工程》 CAS CSCD 北大核心 2015年第16期91-94,103,共5页
目的对产品设计的符号隐喻修辞方法进行解析。方法以设计符号学及语言学的相关理论为基础,对产品符号概述、产品符号化过程、产品符号隐喻修辞方法的分析与应用3个方面进行研究。结论通过对产品符号隐喻修辞的分类研究,归纳出产品设计... 目的对产品设计的符号隐喻修辞方法进行解析。方法以设计符号学及语言学的相关理论为基础,对产品符号概述、产品符号化过程、产品符号隐喻修辞方法的分析与应用3个方面进行研究。结论通过对产品符号隐喻修辞的分类研究,归纳出产品设计的符号显性隐喻分为显性表现自然物和显性表现人造物两种,符号隐性隐喻分为隐性揭示功能、隐性象征文化两种,用以指导若干产品设计实践。 展开更多
关键词 产品符号 隐喻修辞 显性 隐性 设计
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Intranasal endoscopic prelacrimal recess approach to maxillary sinus 被引量:27
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作者 ZHOU Bing HAN De-min CUI Shun-jiu HUANG Qian WANG Cheng-shuo 《Chinese Medical Journal》 SCIE CAS CSCD 2013年第7期1276-1280,共5页
Background The inferior turbinate (IT) and nasolacrimal duct (NLD) are often sacrificed while managing the diffuse lesion of maxillary sinus (MS). We report a new approach to MS without ablation of NLD and IT. M... Background The inferior turbinate (IT) and nasolacrimal duct (NLD) are often sacrificed while managing the diffuse lesion of maxillary sinus (MS). We report a new approach to MS without ablation of NLD and IT. Methods This retrospective study enrolled 19 hospitalized patients (aged from 42 to 68 years) who underwent endoscopic sinus surgery between 2003 and 2008. Twelve patients had inverted papilloma (IP), two had nasal polyps, two had Kubo's postoperative cyst of MS, one had recurrent bone cyst of maxilla, one had dentigerous cyst and one had bleeding of internal maxillary artery secondary to CaldwelI-Luc operation respectively. Two IP patients were excluded from this group since the follow-up time was less than 12 months. The NLD was dissected after removing the anterior bony portion of nasal lateral wall. The prelacrimal recess approach (PLRA) to MS was established when IT-NLD flap was raised medially. The flap was repositioned when MS lesion was removed. Results All the 17 patients had unilateral lesions. Ten MS IP patients were at the T3 Krouse stage. The follow-up ranged from 7 to 60 months. No recurrence was seen in 16 patients. Only one IP patient had a local recurrence in MS. All of them had no any complications. Conclusion The diffuse or severe diseases of MS may be the potential indications for PLRA. 展开更多
关键词 nasal endoscope maxillary sinus prelacrimal recess inferior turbinate nasolacrimal duct
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鼻内镜下泪前隐窝入路治疗上颌窦良性病变 被引量:24
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作者 刘澍 薛少飞 +3 位作者 赵玉琴 贾慧存 鲁宁 朱瑞琴 《中国耳鼻咽喉颅底外科杂志》 CAS 2012年第5期370-373,共4页
目的经鼻内镜下泪前隐窝入路治疗上颌窦良性病变,并探讨其适应证、并发症及手术方式。方法回顾性分析43例经鼻内镜下泪前隐窝入路治疗上颌窦良性病变的病例,其中术前及术后病理确诊的上颌窦内翻性乳头状瘤15例,窦内病变镜下检出菌丝或... 目的经鼻内镜下泪前隐窝入路治疗上颌窦良性病变,并探讨其适应证、并发症及手术方式。方法回顾性分析43例经鼻内镜下泪前隐窝入路治疗上颌窦良性病变的病例,其中术前及术后病理确诊的上颌窦内翻性乳头状瘤15例,窦内病变镜下检出菌丝或孢子的真菌性上颌窦炎8例,上颌窦囊肿12例,上颌窦后鼻孔息肉6例,上颌窦异物2例。所有病例手术前均行鼻窦冠状位或水平位CT扫描。患者在局麻下以下鼻甲前缘为中心切口,解剖内移鼻泪管-下鼻甲瓣经泪前隐窝进入上颌窦腔处理上颌窦内病变,复位鼻泪管-下鼻甲瓣,缝合手术切口并行下鼻道开窗。结果 43例患者术中均完全清除窦内病变,术后随访6~24个月,下鼻甲形态愈合良好,术腔上皮化,无溢泪、面部麻木等并发症。2例上颌窦内翻性乳头状瘤术后6个月局部复发,原手术入路切除,随访1 8个月无复发。3例术后鼻腔粘连,局部分离,随访12个月无复发。结论经鼻内镜下泪前隐窝入路进入上颌窦是一种微创、安全、有效的处理上颌窦良性病变的手术方式,可作为鼻内镜下经中鼻道行上颌窦自然口开窗无法彻底切除窦内病变组织的首选治疗方法。 展开更多
关键词 鼻内镜 泪前隐窝 上颌窦 良性病变
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约束与创造在建筑设计中的应用 被引量:16
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作者 张义忠 《河南大学学报(自然科学版)》 CAS 北大核心 2012年第4期428-431,共4页
建筑设计的过程是分析问题、解决问题的过程,涉及功能、形象、技术等各个方面,这些方面的设计均受到特定的自然环境和人文环境以及法律法规的约束.约束有的呈显性,便于把控,有的呈隐性,须深入思考才能把控.对约束的分析是创造的起点,创... 建筑设计的过程是分析问题、解决问题的过程,涉及功能、形象、技术等各个方面,这些方面的设计均受到特定的自然环境和人文环境以及法律法规的约束.约束有的呈显性,便于把控,有的呈隐性,须深入思考才能把控.对约束的分析是创造的起点,创造的结果又形成新的约束.约束与创造是对立统一的矛盾体,约束是创造的动机和前提,创造是约束的目标和归宿. 展开更多
关键词 建筑设计 约束 显性 隐性 创造
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Identification of the novel recessive gene pi55(t) conferring resistance to Magnaporthe oryzae 被引量:15
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作者 HE XiuYing LIU XinQiong +6 位作者 WANG Li WANGLing LIN Fei CHENG YongSheng CHEN ZhaoMing LIAO YaoPing PAN QingHua 《Science China(Life Sciences)》 SCIE CAS 2012年第2期141-149,共9页
The elite rice cultivar Yuejingsimiao 2 (YJ2) is characterized by a high level of grain quality and yield, and resistance against Magnaporthe oryzae. YJ2 showed 100% resistance to four fungal populations collected f... The elite rice cultivar Yuejingsimiao 2 (YJ2) is characterized by a high level of grain quality and yield, and resistance against Magnaporthe oryzae. YJ2 showed 100% resistance to four fungal populations collected from Guangdong, Sichuan, Liaoning, and Heilongjiang Provinces, which is a higher frequency than that shown by the well-known resistance (R) gene donor culti- vats such as Sanhuangzhan 2 and 28zhan. Segregation analysis for resistance with F2 and F4 populations indicated the re- sistance of YJ2 was controlled by multiple genes that are dominant or recessive. The putative R genes of YJ2 were roughly tagged by SSR markers, located on chromosomes 2, 6, 8, and 12, in a hulked-segregant analysis using genome-wide selected SSR markers with F4 lines that segregated into 3 resistant (R): 1 susceptible (S) or 1R:3S. The recessive R gene on chromosome 8 was further mapped to an interval ~1.9 cM/152 kb in length by linkage analysis with genomic position-ready markers in the mapping population derived from an F4 line that segregated into 1R:3S. Given that no major R gene was mapped to this inter- val, the novel R gene was designated as pi55(t). Out of 26 candidate genes predicted in the region based on the reference genomic sequence of the cultivar Nipponbare, two genes that encode a leucine-rich repeat-containing protein and heavy-metalassociated domain-containing protein, respectively, were suggested as the most likely candidates for pi55(t). 展开更多
关键词 rice blast recessive resistance gene pi55 resistance inheritance gene mapping
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试论体育显性课程与隐性课程的关系 被引量:10
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作者 杜国如 罗小平 《体育科研》 2002年第4期31-32,共2页
体育显性课程和隐性课程是现代体育课程理论研究的重要课题之一。通过文献研究和逻辑分析 ,探讨了体育显性课程和隐性课程的关系 ,两者在课程目标 ,教育内容 ,组织方法 ,教学过程以及课程评价等方面表现出辩证统一性。
关键词 体育 显性课程 隐性课程 课程目标 课程评价 课程改革
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腹针对得气的启示与思考 被引量:13
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作者 王永洲 《中国针灸》 CAS CSCD 北大核心 2011年第2期183-185,共3页
受腹针等针灸新技术临床实践的启发,通过对气至不同认知产生气至针下或气至病所的分析思考,重新解读"气至而有效",提出与一般针感相对应的隐性针感的概念,以临床有效性作为评价得气的标准,为针灸临床向无痛化的方向发展做一... 受腹针等针灸新技术临床实践的启发,通过对气至不同认知产生气至针下或气至病所的分析思考,重新解读"气至而有效",提出与一般针感相对应的隐性针感的概念,以临床有效性作为评价得气的标准,为针灸临床向无痛化的方向发展做一些理论上的探讨。 展开更多
关键词 腹针 得气 气至病所 循经感传 隐性 针感 隐性
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“显性”与“隐性”兼顾的田园综合体规划--以武汉都市田园综合体为例 被引量:14
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作者 张毅 王智勇 《规划师》 北大核心 2018年第8期24-28,共5页
在我国深入推进乡村振兴及美丽乡村建设的背景下,田园综合体规划建设成为促进乡村发展的重要举措。文章从田园综合体规划的"显性"与"隐性"维度出发,探讨了田园综合体产生的背景,从建设体制、空间管理、规范标准和... 在我国深入推进乡村振兴及美丽乡村建设的背景下,田园综合体规划建设成为促进乡村发展的重要举措。文章从田园综合体规划的"显性"与"隐性"维度出发,探讨了田园综合体产生的背景,从建设体制、空间管理、规范标准和乡村事权等方面揭示了田园综合体规划面临的问题,并以武汉都市田园综合体为例,从区域协同、产业发展、"多规合一"、生态保护、旅游策划、体系支撑、效益评估、社会治理和管理经营等角度提出了田园综合体规划的具体对策,明确了区域性、综合性和村民自治等"隐性"规划要素对田园综合体建设发展的重要作用,以期为尚处于实验试点阶段的田园综合体规划提供经验借鉴。 展开更多
关键词 都市田园综合体 显性 隐性 武汉
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Effects of exergaming on motor skill competence,perceived competence,and physical activity in preschool children 被引量:11
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作者 Zan Gao Nan Zeng +2 位作者 Zachary C.Pope Ru Wang Fang Yu 《Journal of Sport and Health Science》 SCIE 2019年第2期106-113,共8页
Background: Few school settings offer opportunities for preschool children to engage in structured physical activity, and only a few studies have been conducted examining exergaming's effectiveness on health outco... Background: Few school settings offer opportunities for preschool children to engage in structured physical activity, and only a few studies have been conducted examining exergaming's effectiveness on health outcomes in this age group. This study's purpose, therefore, was to examine a school-based exergaming intervention's effect on preschool children's perceived competence(PC), motor skill competence(MSC), and physical activity versus usual care(recess), as well as to examine gender differences for these outcomes.Methods: A total of 65 preschool children from 2 underserved urban schools were assigned to 1 of 2 conditions, with the school as the experimental unit:(1) usual care recess group(8 weeks of 100 min of recess/week(5 days £ 20 min)) and(2) exergaming intervention group(8 weeks of100 min of exergaming/week(5 days £ 20 min) at school). All children underwent identical assessments of PC, MSC, and moderate-to-vigorous physical activity(MVPA) at baseline and at the end of the 8 th week.Results: A significant Group £ Time effect was observed for MVPA, F(1, 52) = 4.37, p = 0.04, h2 p= 0.04, but not for PC, F(1, 52) = 0.83, p = 0.37,h2 p= 0.02, or MSC, F(1, 52) = 0.02, p = 0.88, h2 p= 0.00. Specifically, the intervention children displayed significantly greater increased MVPA after8 weeks than the comparison children. Additionally, there was a significant time effect for MSC, F(1, 52) = 15.61, p < 0.01, h2 p= 0.23, and gender effect for MVPA, F(1, 52) = 5.06, p = 0.02, h2 p= 0.09. Although all preschoolers' MSC improved across time, boys demonstrated greater MVPA than girls at both time points.Conclusion: Exergaming showed a positive effect in promoting preschool children's MVPA at school and has the potential to enhance PC and MSC. More research with larger sample sizes and longer study durations are warranted. 展开更多
关键词 Active video games CHILDHOOD OBESITY GENDER differences Moderate-to-vigorous physical activity recess
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Effect of cavity flow control on high-speed train pantograph and roof aerodynamic noise 被引量:12
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作者 Hogun Kim Zhiwei Hu David Thompson 《Railway Engineering Science》 2020年第1期54-74,共21页
The pantograph and its recess on the train roof are major aerodynamic noise sources on high-speed trains.Reducing this noise is particularly important because conventional noise barriers usually do not shield the pant... The pantograph and its recess on the train roof are major aerodynamic noise sources on high-speed trains.Reducing this noise is particularly important because conventional noise barriers usually do not shield the pantograph.However,less attention has been paid to the pantograph recess compared with the pantograph.In this paper,the flow features and noise contribution of two types of noise reduction treatments rounded and chamfered edges are studied for a simplified high-speed train pantograph recess,which is represented as a rectangular cavity and numerically investigated at 1/10 scale.Improved delayed detached-eddy simulations are performed for the near-field turbulent flow simulation,and the Ffowcs Williams and Hawkings aeroacoustic analogy is used for far-field noise prediction.The highly unsteady flow over the cavity is significantly reduced by the cavity edge modifications,and consequently,the noise radiated from the cavity is reduced.Furthermore,effects of the rounded cavity edges on the flow and noise of the pantographs(one raised and one folded)are investigated by comparing the flow features and noise contributions from the cases with and without rounding of the cavity edges.Different train running directions are also considered.Flow analysis shows that the highly unsteady flow within the cavity is reduced by rounding the cavity edges and a slightly lower flow speed occurs around the upper parts of the raised pantograph,whereas the flow velocity in the cavity is slightly increased by the rounding.Higher pressure fluctuations occur on the folded pantograph and the lower parts of the raised pantograph,whereas weaker fluctuations are found on the panhead of the raised pantograph.This study shows that by rounding the cavity edges,a reduction in radiated noise at the side and the top receiver positions can be achieved.Noise reductions in the other directions can also be found. 展开更多
关键词 High-speed TRAIN Aeroacoustics PANTOGRAPH PANTOGRAPH recess CAVITY flow Noise CONTROL
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Polycystic liver disease: Classification, diagnosis, treatment process, and clinical management 被引量:10
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作者 Ze-Yu Zhang Zhi-Ming Wang Yun Huang 《World Journal of Hepatology》 2020年第3期72-83,共12页
Polycystic liver disease(PLD)is a rare hereditary disease that independently exists in isolated PLD,or as an accompanying symptom of autosomal dominant polycystic kidney disease and autosomal recessive polycystic kidn... Polycystic liver disease(PLD)is a rare hereditary disease that independently exists in isolated PLD,or as an accompanying symptom of autosomal dominant polycystic kidney disease and autosomal recessive polycystic kidney disease with complicated mechanisms.PLD currently lacks a unified diagnostic standard.The diagnosis of PLD is usually made when the number of hepatic cysts is more than 20.Gigot classification and Schnelldorfer classification are now commonly used to define severity in PLD.Most PLD patients have no clinical symptoms,and minority with severe complications need treatments.Somatostatin analogues,mammalian target of rapamycin inhibitor,ursodeoxycholic acid and vasopressin-2 receptor antagonist are the potentially effective medical therapies,while cyst aspiration and sclerosis,transcatheter arterial embolization,fenestration,hepatic resection and liver transplantation are the options of invasion therapies.However,the effectiveness of these therapies except liver transplantation are still uncertain.Furthermore,there is no unified strategy to treat PLD between medical centers at present.In order to better understand recent study progresses on PLD for clinical practice and obtain potential directions for future researches,this review mainly focuses on the recent progress in PLD classification,clinical manifestation,diagnosis and treatment.For information,we also provided medical treatment processes of PLD in our medical center. 展开更多
关键词 POLYCYSTIC LIVER DISEASE Autosomal dominant POLYCYSTIC KIDNEY DISEASE Autosomal recessIVE POLYCYSTIC KIDNEY DISEASE Isolated POLYCYSTIC LIVER DISEASE DIAGNOSIS Treatment
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遗传学教学中在细胞与分子水平上理解等位基因的显性与隐性 被引量:11
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作者 邢万金 莫日根 《遗传》 CAS CSCD 北大核心 2015年第1期98-108,共11页
在孟德尔遗传学中显性与隐性描述一对等位基因在杂合体时的功能关系,把在表型上看出效果的等位基因称为显性等位基因,看不出效果的称为隐性等位基因,并由此提出分离定律和自由组合定律,开创了遗传学这一学科。这样的描述最初是逻辑推理... 在孟德尔遗传学中显性与隐性描述一对等位基因在杂合体时的功能关系,把在表型上看出效果的等位基因称为显性等位基因,看不出效果的称为隐性等位基因,并由此提出分离定律和自由组合定律,开创了遗传学这一学科。这样的描述最初是逻辑推理的需要,但对于研究生命结构与功能关系的实验性科学而言,必须在细胞与大分子实体上找到显性与隐性的生物学基础。在遗传学教学中,如何用现代分子遗传学知识诠释经典的显性和隐性概念是教师经常面临的释疑问题。笔者认为要理解等位基因显性和隐性的实质,必须了解等位基因的差异及其产物RNA或蛋白质在细胞中的具体作用。不同等位基因的蛋白质或者RNA产物在细胞内的不同时间、不同地点所起的作用不同,赋予了在细胞、组织或器官水平上能够区分观测到的表型差异,即显性或者隐性。文章根据基因结构的变异、基因调控的差异、基因产物的类型与作用等在细胞与分子水平上分别举例探讨了等位基因显性与隐性的分子实质及其变化,以期在遗传学教学过程中使学生对基因的变异和功能有更全面、更具体的理解。 展开更多
关键词 遗传学 教学 等位基因 显性 隐性
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Inheritance of Perpetual Blooming in Rosa chinensis ‘Old Blush' 被引量:9
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作者 LI Shubin ZHOU Ningning +9 位作者 ZHOU Qing YAN Huijun JIAN Hongying WANG Qigang CHEN Min QIU Xianqin ZHANG Hao WANG Shufang LI Shufa TANG Kaixue 《Horticultural Plant Journal》 SCIE 2015年第2期108-112,共5页
Perpetual blooming is one of the most important biological and economical traits in modern rose, while the genetic basis underlining the control of this trait is poorly investigated. With an aim in dissecting the gene... Perpetual blooming is one of the most important biological and economical traits in modern rose, while the genetic basis underlining the control of this trait is poorly investigated. With an aim in dissecting the genetic determinism of perpetual blooming, we developed six rose populations(OB, W, F1, F2, BC1 OB and BC1W) derived from a WOB population [interspecific diploid hybridization between Rosa chinensis ‘Old Blush'(OB) and R. wichuriana ‘Basye's Thornless'(W)]. Perpetual blooming is absent both in a F1 population with 296 individuals and a BC1 W population(W as the backcross parent) with 150 individuals. However, the perpetual blooming trait showed a typical 3︰1 segregation in a backcross population BC1 OB with OB as the backcross parent. In this population with 300 individuals, 83 plants had the perpetual blooming phenotype while the other 217 featured non-perpetual blooming, indicating that the perpetual blooming trait is very likely controlled by two recessive genes in R. chinensis(rpb1 and rpb2). These genetic data suggest that the inheritance of rose perpetual blooming may be controlled by a complex mechanism. 展开更多
关键词 rose Rosa chinensis perpetual blooming segregating population recessive loci
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