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61.
利用Lowell Beineke和Richard Ringeisen给出的边共色数的界,研究得到了Sm∨Pn和Sm∨Cn的边共色数. 相似文献
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Nathalie Rademacher Romain Pariaut Julie Pate Carley Saelinger Michael T. Kearney Lorrie Gaschen 《Veterinary radiology & ultrasound》2014,55(4):447-452
Pulmonary edema is the most common complication of left‐sided heart failure in dogs and early detection is important for effective clinical management. In people, pulmonary edema is commonly diagnosed based on transthoracic ultrasonography and detection of B line artifacts (vertical, narrow‐based, well‐defined hyperechoic rays arising from the pleural surface). The purpose of this study was to determine whether B line artifacts could also be useful diagnostic predictors for cardiogenic pulmonary edema in dogs. Thirty‐one normal dogs and nine dogs with cardiogenic pulmonary edema were prospectively recruited. For each dog, presence or absence of cardiogenic pulmonary edema was based on physical examination, heartworm testing, thoracic radiographs, and echocardiography. A single observer performed transthoracic ultrasonography in all dogs and recorded video clips and still images for each of four quadrants in each hemithorax. Distribution, sonographic characteristics, and number of B lines per thoracic quadrant were determined and compared between groups. B lines were detected in 31% of normal dogs (mean 0.9 ± 0.3 SD per dog) and 100% of dogs with cardiogenic pulmonary edema (mean 6.2 ± 3.8 SD per dog). Artifacts were more numerous and widely distributed in dogs with congestive heart failure (P < 0.0001). In severe cases, B lines increased in number and became confluent. The locations of B line artifacts appeared consistent with locations of edema on radiographs. Findings from the current study supported the use of thoracic ultrasonography and detection of B lines as techniques for diagnosing cardiogenic pulmonary edema in dogs. 相似文献
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CHEN Tao ZHANG Ya-dong ZHU Zhen ZHAO Ling ZHAO Qing-yong ZHOU Li-hui YAO Shu YU Xin WANG Cai-lin 《水稻科学》2014,21(1):13-19
Restorer line breeding is an important approach to enhance the heterosis and improve the yields of japonica hybrid rice. To improve the selection efficiency of restorer lines for BT-type cytoplasmic male sterility (CMS) in japonica rice, a functional marker InDel-Rf-1a based on the difference of nucleotide sequence in Rf-1a locus between BT-type CMS lines and restorer lines was developed to detect the genotypes of different rice materials. Conventional indica rice varieties, restorer and maintainer lines without 574 bp deletion could restore the fertility for BT-type CMS in japonica rice. By contrast, most conventional japonica rice varieties except Aichi 106 and Yijing 12, with genotype of rf-1arf-1a showed the 574 bp deletion maintained sterility for BT-type CMS lines. To further verify the effect of genotyping detection in Rf-1a locus, this marker was also used to amplify the genomic DNA in different japonica rice restorer lines, CMS lines, hybrids and F2 segregation population, and three genotypes in Rf-1a locus could be distinguished distinctly. Therefore, the marker InDel-Rf-1a could be widely used for genetic identification and marker-assisted selection (MAS) in breeding japonica restorer lines. 相似文献
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GUO Si-bin WEI Yu LI Xiao-qiong LIU Kai-qiang HUANG Feng-kuan CHEN Cai-hong GAO Guo-qing 《水稻科学》2013,20(2):95-102
Introgression line population is effectively used in mapping quantitative trait loci(QTLs),identifying favorable genes,discovering hidden genetic variation,evaluating the action or interaction of QTLs in multiple conditions and providing the favorable experimental materials for plant breeding and genetic research.In this study,an advanced backcross and consecutive selfing strategy was used to develop introgression lines(ILs),which derived from an accession of Oryza minuta(accession No.101133) with BBCC genome,as the donor,and an elite indica cultivar IR24(O.sativa),as the recipient.Introgression segments from O.minuta were screened using 164 polymorphic simple sequence repeat(SSR) markers in the genome of each IL.Introgressed segments carried by 131 ILs covered the whole O.sativa genome.The average number of homozygous O.minuta segments per introgression line was about 9.99.The average length of introgressed segments was approximate 14.78 cM,and about 79.64% of these segments had sizes less than 20 cM.In the genome of each introgression line,the O.minuta chromosomal segments harbored chromosomal fragments of O.sativa ranging from 1.15% to 27.6%,with an overall average of 8.57%.At each locus,the ratio of substitution of O.minuta alleles had a range of 1.5% 25.2%,with an average of 8.3%.Based on the evaluation of the phenotype of these ILs,a wide range of alterations in morphological and yield-related traits were found.After inoculation,ILs 41,11 and 7 showed high resistance to bacterial blight,brown planthopper and whitebacked planthopper,respectively.These O.minuta-O.sativa ILs will serve as genetic materials for identifying and using favorable genes from O.minuta. 相似文献
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[目的]研究自选的7个辣椒自交系数量性状的配合力分析。[方法]以7个自选辣椒自交系为亲本,按照不完全双列杂交(4×3)配成12个组合,对各组合的5个性状进行了方差分析,在此基础上进行了配合力分析。[结果]T-1、04-39一般配合力较高,组合0702是一个强优势组合。[结论]该研究可为进一步培育辣椒新品种提供参考依据。 相似文献
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以温敏型核雄性不育系番茄T4及对照First为试材,通过调查花粉发芽率、自交结实率、果实种子数以及采用Tricine-SDS-PAGE电泳方法分析叶片及花药蛋白质的变化,研究T4的育性转化,并分析其在可育和不育条件下花粉发芽率、自交结实率、果实种子数、叶片及花药蛋白质的差异。结果表明:28 ℃/18 ℃(昼/夜)处理的T4花粉发芽率、自交结实率最高,果实种子数最多,与对照First差异不显著,表明此时T4恢复部分育性|28 ℃/24 ℃和28 ℃/12 ℃处理的T4花粉发芽率、自交结实率和果实种子数与对照差异均达到极显著水平,表现为不育。不同温度处理的T4花药蛋白质与叶片蛋白质差异均达到显著水平|28 ℃/24 ℃和28 ℃/12 ℃处理的T4叶片蛋白质与对照差异显著,但28 ℃/18 ℃处理的差异不明显。 相似文献