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1.
Summary Mitochondrial DNA (mtDNA) diversity has been determined in apple landraces and cultivars, based upon restriction fragment length polymorphisms (RFLPs) for several mitochondrial genes. Our analysis includes three cultivars, Golden Delicious, McIntosh and Delicious, which represent the various patterns of mtDNA polymorphisms previously described (Ishikawa et al., 1992). A total of five RFLPs were detected, allowing classification of the apple genotypes into four cytoplasmic groups: GroupI, Golden Delicious-type; GroupII, McIntosh-type; GroupIII, Delicious-type; and Group IV, Dolgo Crab-type. European landraces and cultivars were assigned to Groups I, II, and III, while chinese crab apples were placed in either Group III or IV. 相似文献
2.
3.
Three apple (Malus×domestica) cultivars and 11 Malus accessions have been investigated by the probe hybridization method on their mitochondrial DNA (mtDNA). The gene probes used were: coxI, coxII, atpA, atp6, and atp9. Our results revealed enough variation to characterize ten mtDNA haplotypes among the Malus genotypes examined. The taxonomic and phylogenetic implications of mtDNA polymorphism are also discussed. 相似文献
4.
Yoshiya Shimamoto Hirofumi Fukushi Jun Abe Akira Kanazawa Junyi Gai Zhong Gao Donghe Xu 《Genetic Resources and Crop Evolution》1998,45(5):433-439
RFLPs of chloroplast (cp) and mitochondrial (mt) DNA have been used to characterize the cytoplasmic genome of wild soybean, Glycine soja, growing in China. We have found from the RFLPs of that the cytoplasmic genomes of most Chinese wild soybeans have a combination of cpIII with mt-a or a combination of cpII with mt-b accompanied by mtIV or mtV according to our classification. CpII was not observed in combination with mt-a and cpIII was not observed in combination with mt-b. The regional distribution of these two types showed clines with opposite directions. The Yangtze River Valley had the greatest diversity in each of cp and two mt profiles detected in this study and the cytoplasmic genome combining these three profiles showed the highest degree of polymorphism in this region. The Yangtze River Valley may be a center of cytoplasmic diversity of wild soybean and may contain various genetic resources of soybean. 相似文献
5.
A large numbers of samples of wild soybean accessions and cultivated soybean landraces from various areas in China were analyzed by isozyrme, cytoplasmic DNA RFLP and nuclear DNA RAPD markers in order to reveal their genetic diversity. Greater comprehensive genetic diversity was detected in wild soybean than in cultivated soybean. The genetic plentifulness and the genetic dispersion of wild soybean were 180 (95. 2%) and 0. 2891 while those of cultivated soybean were 154(81.5%) and 0. 2091,respectively. On the most loci, especially on isozyme loci Idh1, Aph, Idh2,and Dia, cytoplasmic DNA RFLP loci cp Ⅰ , cp Ⅲ, mt Ⅳ a and mt Ⅳ b, and nuclear RAPD loci OPAP4-8, OPAP5-1, OPAP9-8 and OPAP20-8, the wild soybeans djffered remarkably from the cultivated ones in allele frequency. These markers could be used in further study on the evolution and origin of the cultivated soybean. 相似文献
6.
To characterize the mechanism of the reaction of lignin with aqueous acetic acid (AW) containing a small amount of H2SO4, guaiacylglycerol--guaiacyl ether (GOG), and guaiacylglycerol--syringol ether (GOS) were refluxed in 90% AW with 0.28% H2SO4 for 0–120 min. Reaction products and their silylated derivatives were characterized by analytical methods such as gas chromatography-mass spectrometry and nuclear magnetic resonance. When the model compounds were allowed to react at boiling temperature for 0 min (heat-up time 30 min), most of their primary alcohol groups and some of their secondary alcohol groups were acetylated, but their phenolic groups were not. About 90% of GOG was degraded, polymerized, or both during boiling for at least 15 min, yielding guaiacol and isocoumaran compounds (GOG-e and GOG-f) in addition to homovanillin (II) as guaiacylvinyl alcohol (I) and other minor products. GOS yielded syringol, homovanillin (II), and a novel compound (V) together with unknown products but not the corresponding isocoumaran compounds. 相似文献
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8.
Maiko Sato Ashraf M Ahmed Ayako Noda Hitoshi Watanabe Yukio Fukumoto Tadashi Shimamoto 《Acta veterinaria Scandinavica》2009,51(1):46
Imported animals, especially those from developing countries, may constitute a potential hazard to native animals and to public health. In this study, a new flock of lesser flamingos imported from Tanzania to Hiroshima Zoological Park were screened for multidrug-resistant Gram-negative bacteria, integrons and antimicrobial resistance genes. Thirty-seven Gram-negative bacterial isolates were obtained from the flamingos. Seven isolates (18.9%) showed multidrug resistance phenotypes, the most common being against: ampicillin, streptomycin, tetracycline, trimethoprim/sulfamethoxazole and nalidixic acid. Molecular analyses identified class 1 and class 2 integrons, β-lactamase-encoding genes, blaTEM-1 and blaCTX-M-2 and the plasmid-mediated quinolone resistance genes, qnrS and qnrB. This study highlights the role of animal importation in the dissemination of multidrug-resistant bacteria, integrons and antimicrobial resistance genes from one country to another. 相似文献
9.
Saishu YOSHIDA Masashi HIGUCHI Hiroki UEHARU Naoto NISHIMURA Mitsuyoshi TSUDA Hideji YAKO Mo CHEN Hideo MITSUISHI Yoshiya SANO Takako KATO Yukio KATO 《The Journal of reproduction and development》2014,60(4):295-303
The pituitary is an important endocrine tissue of the vertebrate that produces and secretes many hormones. Accumulating data
suggest that several types of cells compose the pituitary, and there is growing interest in elucidating the origin of these cell
types and their roles in pituitary organogenesis. Therein, the histogenous cell line is an extremely valuable experimental tool
for investigating the function of derived tissue. In this study, we compared gene expression profiles by microarray analysis and
real-time PCR for murine pituitary tumor-derived non-hormone-producing cell lines TtT/GF, Tpit/F1 and Tpit/E. Several genes are
characteristically expressed in each cell line: Abcg2, Nestin, Prrx1,
Prrx2, CD34, Eng, Cspg4 (Ng2),
S100β and nNos in TtT/GF; Cxcl12, Raldh1,
Msx1 and Twist1 in Tpit/F1; and Cxadr, Sox9,
Cdh1, EpCAM and Krt8 in Tpit/E. Ultimately, we came to the following conclusions: TtT/GF cells
show the most differentiated state, and may have some properties of the pituitary vascular endothelial cell and/or pericyte.
Tpit/F1 cells show the epithelial and mesenchymal phenotypes with stemness still in a transiting state. Tpit/E cells have a
phenotype of epithelial cells and are the most immature cells in the progression of differentiation or in the initial
endothelial-mesenchymal transition (EMT). Thus, these three cell lines must be useful model cell lines for investigating pituitary
stem/progenitor cells as well as organogenesis. 相似文献
10.
Transition between frictional slip and ductile flow for halite shear zones at room temperature 总被引:1,自引:0,他引:1
Shimamoto T 《Science (New York, N.Y.)》1986,231(4739):711-714
A complete transition from frictional slip to ductile shearing flow upon decreasing velocity (or slip rate) or increasing confining pressure is documented for a thin layer of halite undergoing large shearing deformation. The results indicate that the logarithmic law for steady-state friction with a negative velocity dependence breaks down when friction becomes nearly equal to the shear resistance required for ductile flow and that the law changes into a flow law in shear upon further decrease in velocity. The frictionvelocity relation is crucial in stability analyses of fault motion, and the results are important for earthquake and state-of-stress problems, especially in the application of laboratory data to the slow average motion of natural faults and to the behavior of deep faults along which ductile deformation becomes increasingly predominant. 相似文献