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91.
After crosses of multiple rape-radish chromosome additions with rape, nine different monosomic additions (2n = 4x = 38 + 1) of individual radish chromosomes, a–i, were isolated, having the genomic background of winter oil seed rape and radish cytoplasm. Extra chromosomes were identified with RAPD markers, specific for individual radish chromosomes. All radish-plasmic monosomic additions, except that of chromosome f, had low seed production due to pistilloid stamens. Rape cytoplasm was substituted by crossing the monosomic additions as pollinators to rape followed by reselection of the radish chromosome additions. The monosomic additions in rape cytoplasm showed normal male fertility. Average transmission rates of radish chromosomes via egg cells and pollen cells were 37% and 27%, respectively. Lowest male transmission was found for chromosomes e and f with 0.04 and 0.01. Monosomic additions were self-pollinated to produce disomic additions. Monosomic and disomic addition progenies were discriminated by a prescreening with quantitative double primer (dp) RAPDs and cytological confirmation of preselected candidates by FISH analysis using a Raphanus-specific probe. Usability of this complete set of nine disomic rape-radish additions (2n = 4x = 38 + 2) was discussed.  相似文献   
92.
构建染色体BAC文库对于简化拥有庞大基因组植物的测序、物理作图和基因克隆具有重要意义。分选染色体的鉴定是整个文库构建过程的关键环节之一。 本文在前人研究的基础上, 分别采用荧光原位杂交(FISH)、原位PCR(C-PRINS)和PCR方法, 对分选的6VS、3B和7BL染色体(臂)进行了鉴定。结果表明, 这3种方法都能对流式分选染色体进行有效鉴定, 其中PCR法速度最快、重复性好, 但结果不具可视性、也不能鉴定分选纯度; 而FISH法重复性好、结果具有可视性、能够鉴定分选纯度, 但操作程序复杂耗时, 受探针特异性的限制; C-PRINS法则综合了上述两种方法的优点, 是最具潜力的鉴定方法, 如果与液体原位杂交相结合, 有可能为解决染色体分选问题开辟新的途径, 但也存在重复性差、杂交信号不稳定的缺点。  相似文献   
93.
In this study, multicolor fluorescence in situ hybridization (FISH) analysis on metaphase chromosomes of spinach with biotin-labeled 25S rDNA, DIG-labeled telomere sequences and biotin-labeled and DIG-labeled 5S rDNA was performed. There were six 25S rDNA loci located on the satellites of the third, the fifth and the sixth chromosomes, and four 5S rDNA loci located on the long arms of the third and the fifth chromosomes. The telomere loci were located on the end of the sixth chromosome and also on both the end and centromeric regions of other chromosomes. This study is an important complement to both traditional karyotype analysis and FISH karyotype analysis in spinach. __________ Translated from Hereditas (Beijing), 2007, 29(11): 1405–1408 [译自: 遗传(北京)]  相似文献   
94.
Chromosomal karyotypes of Oreochromis mossambicus and O. urolepis hornorum and their hybrid were analysed by means of Cot‐1 DNA bandings through fluorescence in situ hybridization (FISH). To identify all chromosomes, Cot‐1 DNA – which contains highly and moderately repetitive DNA – was extracted from genomic DNA, labelled as a probe with Dig‐11‐dUTP, and in situ hybridized to spreads of mitotic chromosomes of the three samples. The hybridized signals were detected by means of Cy3‐conjugated antidigoxigenin. The FISH results indicated that the three samples had the same diploid number (2n=44) of chromosomes. Specific fluorescence signal bands were detected on all individual chromosome pairs. On the basis of Cot‐1 DNA FISH banding patterns and chromosome morphology, the karyotypes of the three samples have been constructed; no remarkable differences were detected between the karyotypes of these species using this method. These results – which are similar to those reported previously, with respect to chromosome number, morphology and Cot‐1 DNA FISH patterns – suggest chromosomal stasis during speciation and hybridization of tilapia (Oreochromis, Cichlidae). Such a molecular cytogenetic procedure, if used in conjunction with other genomic research methods, could facilitate the study of genomic structure and be adapted for chromosome studies of other animal species.  相似文献   
95.
为了给小麦育种提供新的种质资源,对4份圆锥小麦-乌拉尔图小麦双二倍体(AABBA^uA^u)的农艺性状、染色体组成及高分子量谷蛋白亚基组成进行了鉴定。农艺性状调查结果表明,4份双二倍体的株高介于108.45~129.43 cm,分蘖数介于7.3~17.5个,穗长介于10.23~12.17 cm,小穗数介于16.26~22.06,自交结实率介于37.77%~70.46%;4份双二倍体对目前的流行条锈菌混合生理小种(条中31、条中32、条中33、条中34和水源11-4)均表现为高抗。利用寡核苷酸序列探针Oligo-pSc119.2-1、Oligo-pTa535-1、Oligo-pTa71-2、pTa-713和简单重复序列探针(AAC)5进行FISH分析,可区分出圆锥小麦-乌拉尔图小麦双二倍体的42条染色体。花粉母细胞染色体配对观察表明,在这些双二倍体的减数分裂中期I,染色体大多配对成二价体,仅有少量的单价体、三价体和四价体。SDS-PAGE分析表明,来自于乌拉尔图小麦TA#831的1Ay亚基在双二倍体Syn-TAU-2中得到了表达,但其迁移率发生了变化;来自于PI428270和PI428274的1Ax和1Ay亚基分别在双二倍体Syn-TAU-3和Syn-TAU-4中得到了表达。这些双二倍体可作为新的资源材料用于普通小麦的遗传改良。  相似文献   
96.
采用变性梯度凝胶电泳(DGGE)和寡聚核苷酸探针-荧光原位杂交(FISH)方法研究了十溴联苯醚(BDE209)对土壤中微生物群落的影响作用。结果表明,1mg·kg^-1 BDE209对土壤中微生物群落多样性以及总细菌数有明显的促进作用,土壤中的氨氧化细菌以及亚硝酸氧化菌的数量有显著增长。BDE209浓度达到100mg·kg^-1时,土壤微生物的总数和群落多样性则显著降低,同时氨氧化细菌以及亚硝酸氧化菌的生长也受到明显的抑制。暗室培养45d内,BDE209虽未被降解,但高浓度的十溴联苯醚会对土壤中的微生物群落结构及土壤潜在的硝化作用产生较大影响。  相似文献   
97.
An 8-year-old male neutered Labrador Retriever was referred to the University of Wisconsin Veterinary Medical Teaching Hospital with a presumptive diagnosis of leukemia. Hematologic abnormalities included normal neutrophil count with a left shift, monocytosis, eosinophilia, thrombocytopenia, and circulating immature mononuclear cells. Bone marrow was effaced by immature hematopoietic cells of various morphologic appearances. In addition, large multinucleated cells were observed frequently. Flow cytometric analysis of nucleated cells in blood revealed 34% CD34(+) cells, consistent with acute leukemia. By immunocytochemical analysis of cells in blood and bone marrow, some mononuclear cells expressed CD18, myeloperoxidase, and CD11b, indicating myeloid origin; some, but not all, large multinucleated cells expressed CD117 and CD42b, the latter supporting megakaryocytic lineage. The diagnosis was acute myeloblastic leukemia without maturation (AML-M1). To identify genetic aberrations associated with this malignancy, cells from formalin-fixed paraffin-embedded bone marrow were analyzed cytogenetically by multicolor fluorescence in situ hybridization (FISH). Co-localization of bacterial artificial chromosome (BAC) containing BCR and ABL was evident in 32% of cells. This confirmed the presence of the canine BCR-ABL translocation or Raleigh chromosome. In people, the analogous translocation or Philadelphia chromosome is characteristic of chronic myelogenous leukemia (CML) and is rarely reported in AML. BCR-ABL translocation also has been identified in dogs with CML; however, to our knowledge this is the first report of AML with a BCR-ABL translocation in a domestic animal.  相似文献   
98.
胶乳转化酶(Invertase,Inv)是控制橡胶树胶乳蔗糖代谢和影响胶乳(橡胶)产量的关键酶。已有研究证实了胶乳转化酶属于中性/碱性转化酶。本研究以热研7-33-97(2n=36)为材料制备叶片细胞染色体标本,采用荧光原位杂交技术(fluorescence in situ hybridization,FISH)对胶乳转化酶基因HbNIN1、HbNIN2和HbNIN3进行了染色体物理定位的初步研究。结合核型分析,初步确定HbNIN1基因位于5号染色体的长臂上,其信号位点到着丝粒的百分距离为33.1;HbNIN2基因位于2号染色体的长臂上,其信号位点到着丝粒的百分距离为35.7;HbNIN3基因位于3号染色体的短臂上,其信号位点到着丝粒的百分距离为40.42。由此揭示了该基因家族在染色体上的位置和分布特点。  相似文献   
99.
Festulolium is a hybrid between Festuca and Lolium species that has valuable agronomic traits from both grass species. The purpose of our breeding program is to produce hexaploid festulolium that introduces tolerance to summer depression into Italian ryegrass (Lolium multiflorum) by crossing it with tall fescue (Festuca arundinacea). However, we found the DNA ploidy of hexaploids was not stable and was reduced in successive generations. We aimed to find out how to obtain stable high-ploidy festulolium. F1 hybrids of L. multiflorum and F. arundinacea were produced. The F3 generation was produced from putative hexaploid F2 individuals by open pollination. The F4 to F6 generations were obtained by polycrossing. The DNA ploidy levels of F2 to F6 individuals were estimated by flow cytometry. Cytological characteristics of the F5 and F6 individuals were investigated by FISH and GISH. The DNA ploidy level of hexaploid festulolium was reduced and stabilized at almost the same level as a tetraploid. Seed fertility was inversely correlated with an increase in ploidy level. GISH revealed no preferential Lolium transmission. FISH with a telomere probe revealed that counting the exact number of chromosomes in festulolium was difficult. DNA ploidy level was strongly correlated with the number of chromosomes.  相似文献   
100.
为探究反硝化除磷-诱导结晶磷回收工艺中缺氧池污泥释磷、吸磷以及微生物特征,利用荧光原位杂交(fluorescence in situ hybridization,FISH)技术、电子扫描显微镜(scanning electron microscope,SEM)观察了微生物的数量、分布和形态;通过批次试验考察了污泥在厌氧/好氧和厌氧/缺氧2种模式下的释磷和吸磷特征。结果表明:该双污泥系统缺氧池中聚磷菌占总细菌比例的69.7%,明显高于单污泥系统中富集的聚磷菌比例,污泥中的微生物多呈杆状;厌氧/好氧、厌氧/缺氧模式下单位污泥浓度(mixed liquor suspended solids,MLSS)总吸磷量(以PO43--P计)分别为22.84、18.60 mg/g,反硝化聚磷菌(denitrifying polyphosphate-accumulating organisms,DPAO)占聚磷菌(polyphosphate-accumulating organisms,PAO)的比例为81.44%,表明在长期的厌氧/缺氧运行条件下可以富集到以硝酸盐为电子受体的反硝化聚磷菌,同时还存在着仅以氧气为电子受体的聚磷菌;通过pH值和氧化还原电位(oxidation reduction potential,ORP)的实时监测可以快速地了解污水生物处理系统中各类反应的进程,对调控工艺参数有着重要的意义。综上所述,为保证污水生物处理工艺的正常稳定运行,将微生物分析与常规的化学参数分析结合起来考察将是未来发展的必然趋势。  相似文献   
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