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141.
142.
Sasanuma T Chabane K Endo TR Valkoun J 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2004,108(4):612-618
Intra- and inter-specific genetic variation was investigated in seven diploid Aegilops species using the amplified fragment length polymorphism (AFLP) technique. Of the seven species, the cross-pollinating Aegilops speltoides and Aegilops mutica showed high levels of intraspecific variation whereas the remaining five self-pollinating species showed low levels. Aegilops bicornis, Aegilops searsii and Ae. speltoides formed one cluster in the dendrograms, while Aegilops caudata and Aegilops umbellulata formed another. Relationships among the species inferred were more consistent with the relationships inferred from studies of chromosome pairing in interspecific hybrids, and previous molecular phylogenetic reconstructions based on nuclear DNA, than they were with those based on molecular plasmon analysis, suggesting that the nuclear genome has evolved differently from the cytoplasmic genome in the genus Aegilops.Communicated by J. Dvorak 相似文献
143.
Okina M Yoshida K Kuroda K Wanibuchi H Fukushima S Endo G 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2004,799(2):209-215
A method for the determination of trivalent arsenicals in urine was examined. Trivalent arsenicals, extracted as complexes with diethylammonium diethyldithiocarbamate (DDDC) into carbon tetrachloride, were determined by liquid chromatography-inductively coupled plasma mass spectrometry (LC-ICP-MS). The trivalent methylated arsenicals monomethylarsonous acid (MMA(III)), dimethylarsinous acid (DMA(III)), and trimethylarsine (TMA) were detected in urine of rats that had received dimethylarsinic acid (DMA(V)) or monomethylarsonic acid (MMA(V)) at concentration of 200 microg ml(-1) in drinking water for 24 weeks. This method is the first to permit quantification of trivalent methylated arsenicals in urine without significant changes in concentration during storage or pretreatment. 相似文献
144.
145.
A member of Forkhead transcription factor FKHRL1 is a downstream effector of STI571-induced cell cycle arrest in BCR-ABL-expressing cells 总被引:6,自引:0,他引:6
Komatsu N Watanabe T Uchida M Mori M Kirito K Kikuchi S Liu Q Tauchi T Miyazawa K Endo H Nagai T Ozawa K 《The Journal of biological chemistry》2003,278(8):6411-6419
146.
147.
The complete primary structure of MSP-1, a major water-soluble glycoprotein in the foliated calcite shell layer of the scallop
Patinopecten yessoensis, is reported. The full-length complementary DNA for MSP-1 isolated by polymerase chain reaction contained a sequence for a
signal peptide of 20 amino acids followed by a polypeptide of 820 amino acids with calculated molecular mass of 74.5 kDa.
The deduced amino acid sequence of MSP-1 includes a high proportion of Ser (32%), Gly (25%), and Asp (20%), and the predicted
isoelectric point is 3.2; in these respects, MSP-1 is a typical acidic glycoprotein of mineralized tissues. A repeated modular
structure characterizes MSP-1, with a sequence unit between 158 and 177 amino acids in length being repeated 4 times in tandem
in the middle part of the protein. The repeated unit comprises 3 modules (SG, D, and K domains), each having a distinct amino
acid composition and sequence. The SG domain is almost exclusively composed of Ser and Gly residues. The D domain is rich
in Asp residues, potential N-glycosylation and phosphorylation sites. The K domain is rich in Gly residues and has a core of basic residues. The Asp residues
are arranged more or less regularly in the D domains, exhibiting some repeated motifs such as Asp-Gly-Ser-Asp and Asp-Ser-Asp.
Further, the 4 D domains indicate remarkable overall sequence similarities to each other. These observations suggest that
the regular arrangements of COO− groups in the D domain side chains may be important for specific control of crystal growth.
Received September 19, 2000; accepted February 9, 2001 相似文献
148.
Kitamoto D Yanagishita H Endo A Nakaiwa M Nakane T Akiya T 《Biotechnology progress》2001,17(2):362-365
Antiagglomeration effects of different surfactants on ice slurry formation were examined to improve the efficiency of an ice-water slurry system to be used for cold thermal storage. Among the chemical surfactants tested, a nonionic surfactant, poly(oxyethylene) sorbitan dioleate, was found to show a greater antiagglomeration effect on the slurry than anionic, cationic, or amphoteric surfactants. More interestingly, diacylmannosylerythritol, a glycolipid biosurfactant produced by a yeast strain of Candida antarctica, exhibited a remarkable effect on the slurry, attaining a high ice packing factor (35%) for 8 h at a biosurfactant concentration of 10 mg/L. These nonionic glycolipid surfactants are likely to effectively adsorb on the ice surface in a highly regulated manner to suppress the agglomeration or growth of the ice particles. This is the first report on the utilization of biosurfactant for thermal energy storage, which may significantly expand the commercial applications of the highly environmentally friendly slurry system. 相似文献
149.
150.
An anhydrous polymorphic form of trehalose 总被引:1,自引:0,他引:1
An anhydrous polymorphic form of alpha,alpha-trehalose was prepared from trehalose dihydrate by two different drying methods: (1) heating under vacuum; and (2) heating in hot air. Preparation of this anhydrous form by vacuum heating showed good reproducibility. This form was characterized by X-ray powder diffraction analysis and differential scanning calorimetry. This anhydrous form was converted to an amorphous phase at 127 degrees C and was found to be hygroscopic. At 43% relative humidity at 25 degrees C, this form rapidly reverted to dihydrate, while the amorphous phase remained unchanged. When an amorphous phase coexisted with this form, the rate of water adsorption to the amorphous phase was slower than that to the amorphous phase alone. These properties of this anhydrous form of alpha,alpha-trehalose may explain the effects of trehalose in dehydration tolerance of plants and insects in the desert. 相似文献