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采用表面铺展,磷钨酸染色技术制备褐家鼠精母细胞的联会复合体。根据对10个精母细胞的测量结果,绘制了联会复合体组型图,与大鼠的染色体组型作比较。并应联会复合体上着丝粒的嗜银性问题进行了讨论。  相似文献   

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采用低渗、滴片和硝酸银染色技术,对棕色田鼠的联会复合体和减数分裂中期Ⅰ染色体轴的形成过程及其两者问的关系进行了分析研究。结果表明:联会复合体起始于偶线期,成熟于粗线期,于早双线期到中双线期解体;而中期Ⅰ染色体轴是在晚双线期才开始形成。二者之间存在一个无任何轴性结构的时期。联会复合体与中期Ⅰ染色体轴是减数分裂染色体中先后出现的两种不同的轴性结构。  相似文献   

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以表面铺展法制备棕色田鼠精母细胞联会复合体标本,经硝酸杂色作电镜观察,结果表明,在减数分裂前期IX和Y染色体的形态和行为同常染色体有明显差异;XY染色体的配对起始于早精线期,成熟于中一期,在晚粗线期先于常染色体解地;X染然水与对区自身折叠,形成发夹状结构。  相似文献   

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运用表面铺展硝酸银染色联会复合体的电镜技术,对中国人精母细胞中XY配对形态和行为进行电镜观察,根据XY配对复杂形态和行为变化将XY配对分为六个阶段,XY配对延迟至晚偶线期-早粗线期,在早粗线期阶段,配对长度占Y轴全长的30%-50%,到中粗线期配对区开始缩短,在晚粗线期-早双线期解联会,不配对片段常常撕裂成多股,在XY配对Ⅲ型精母细胞中,可见到X与Y长臂远端联合现象(称为次级联合),还对XY配对同源性问题作了进一步的讨论。  相似文献   

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棕色田鼠精母细胞中联会复合体的研究   总被引:1,自引:1,他引:0  
以表面铺展法制备棕色田鼠精母细胞联会复合体标本,经硝酸银染色作电镜观察.结果表明,在减数分裂前期 I X 和 Y 染色体的形态和行为同常染色体有明显差异; X Y 染色体的配对起始于早粗线期,成熟于中粗线期,在晚粗线期先于常染色体解联会; X 染色体未配对区域自身折叠,形成发夹状结构  相似文献   

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犏牛精母细胞联会复合体与雄性不育关系的研究   总被引:2,自引:0,他引:2  
采用界面铺展硝酸银染色技术,研究了公犏牛的精母细胞联合复合体(synaptonemalcomplex,SC),结果表明:(1)在减数分裂过程中仅有少数精母的常染色体能形成SC结构,X、Y染色体轴 围虽积聚有许多微小的深色颗粒状物质,但未见X、Y染色体的明显联会(2)在常染色体的联会中,有较多的三价体、插入环等联会异常现象;(3)常染色体SC相对长度与体细胞染色体的相对长度间有显著相关性(R=096  相似文献   

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以亚离子和He-Ne激光照射活体雄性小鼠睾丸,观察小鼠睾丸中精母细胞的联会复合体。发现小鼠精母细胞的联会复合体发生一定程度的畸变,说明激光辐射不仅可造成哺乳动物表面组织热损伤,还有可能诱发染色体变异,这对今后激光在遗传育种方面的进一步开发应用有重要意义。  相似文献   

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Oocytes collected from prepubertal gilt ovaries were matured in vitro (IVM), and fertilized in vitro (IVF) or electrically activated. Phosphorylation of mitogenactivated protein kinase (MAPK) was detected with SDS-PAGE and Western blotting, and translocation of ERK2 was observed with immunofluorescent cytochemistry. We found that the quantity of MAPK kept unchanged during oocyte maturation. There was no phosphorylated MAPK in porcine oocytes at the germinal vesicle (GV) stage; a little MAPK was phosphorylated at 20 h of IVM; a high level phosphorylation was detected at 30 h, while MAPK phosphorylation decreased at 36 h; and then MAPK phosphorylation increased again to the peak level from 40 to 60 h. ERK2 translocated from the peripheral cytoplasm to inner cytoplasm and nuclear area during oocyte maturation. There was nearly no phosphorylated MAPK at 18 and 20 h of electrically activated oocytes, but phosphorylation increased at 22 h. There was no phosphorylated MAPK at 12 h of IVF, while phosphorylation resumed at 16 h. These results suggest that MAPK may play an important regulatory role in MI-MII transition, pronucleus formation and the initiation of the first mitosis in pig eggs.  相似文献   

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文章就《说文段注》中"某行某废"所说的字词进行考察,借此分析汉字词的演变情况,得出汉字演变的一般规律;同时对段注中关于假借的观点进行探讨。  相似文献   

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中国三维水墨动画,作为中国原创动画片种——水墨动画的延续物,其发展空间巨大,但目前未得到足够关注.通过对中国三维水墨动画现状分析,找出其存在的局限性,并提出几点建设性思考,从而为发展独具中国民族特色的三维水墨动画,提供借鉴和参考,以期为当前中国动画产业的发展,探索出一条符合本国国情的动画之路.  相似文献   

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在整个基础教育阶段,语文课程常常是争议最大的;而在语文课程中,文学教育又是争议最大、受到社会各种因素影响最多的问题.焦点主要在下面几个问题:汉语言文学教育的中国文化思维特性;文学界与语文界的两条话语系统的时间差;文学理论对于文学教育的影响;语文课程中文学作品的选文问题;作为"例子"的文学教育与作为"精神"的文学教育.  相似文献   

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设计一对PCR引物,寡聚核苷酸序列的上游引物为5’-gCg,AAT,TCA,TCC,CAC,gTg,CCT,gC-3’,下游引物为5’-gAg,AAT,TCC,Tgg,ggA,ggg,ACC,TT-3’。经68℃退火及30轮循环的PCR程序后,分别克隆了来自我国甘肃、青海和云南地区牦牛β乳球蛋白基因的5’调控区1447bp的DNA片段。将该片段从琼脂糖凝胶中回收,克隆在pMD18-T Vector后进行序列测定。序列分析结果表明,甘肃牦牛与青海牦牛该序列的核苷酸同源性为98、13%,与云南牦牛该序列的核苷酸同源性为97.65%,青海牦牛与云南牦牛该基因片段的核苷酸序列同源性为99.45%。  相似文献   

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Metal_radical method is an effective approach to synthesizing magnetic molecular materials. With the development in decades, the study of nitroxide_metal complexes has made great progress in model, theoretical treatment and design of molecules. Several mechanisms of the metal_radical magnetic coupling are discussed. Molecular magnetic project of nitroxide_metal complexes has made fruitful achievements, but crystal magnetic project is difficult to be controlled, and it is a challenge to chemists. The studies on nitronyl nitroxide_metal complexes are summarized. At present, there are three major approaches to increasing the T c of the metal_radical compounds: (ⅰ) Searching for nitronyl nitroxide ligands that can yield 3_D ferro_ or ferrimagnetic structures; (ⅱ) decorating the structure of radicals with the aim to enhance the coordinate capability of radicals; (ⅲ) grafting polynitroxide radicals as a versatile bridge. The third approach, namely searching for polynitroxide ligand, will serve as a hopeful strategy for exploring higher T c radical molecule_based magnets.  相似文献   

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