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421.
Three hardwoods of varying vessel arrangement were treated with the ionic liquid, 1-ethyl-3-methylimidazolium chloride ([C2mim][Cl]), which can dissolve cellulose, to investigate its influence on wood tissue morphology. Characterization was carried out by light and scanning electron microscopy. The wood fibers of all species swelled significantly during [C2mim][Cl] treatment. The swelling behavior varied according to wood species and differed from other cell types such as ray parenchyma cells. Morphological changes of the pits also varied between wood species. Treatment with [C2mim][Cl] affects wood tissues differently depending on wood species and cell type. These differences are not due to the vessel arrangement and its presence, but possibly from the chemical component and the microfibril angle of various wood tissues.  相似文献   
422.
Efficiencies of SCAR, CAPS and PCR-RF-SSCP marker production were investigated using two combinations of breeding lines in Brassica oleracea. Published EST sequences of B. oleracea, Brassica rapa, Brassica napus, and Arabidopsis thaliana and newly determined nucleotide sequences of anther cDNA clones from B. oleracea were used for designing primer pairs to amplify genes. The percentage of primer pairs yielding DNA amplification of a single gene was higher in primer pairs of B. oleracea (91%) than those of B. rapa (56%) and A. thaliana (17%). Single DNA fragments amplified by 9% of the primer pairs showed polymorphism as SCAR markers between a broccoli line and a Chinese kale line by agarose-gel electrophoresis. CAPS analysis showed different band patterns in 32% of the same-sized DNA fragments, and PCR-RF-SSCP analysis revealed DNA polymorphism in 52% of those showing no DNA polymorphism by CAPS. In total, 71% of the single DNA fragments were converted to DNA markers. The frequency of DNA polymorphism between parental lines of a cabbage F1 hybrid was lower, 5% by SCAR and 12% by CAPS. However PCR-RF-SSCP analysis revealed DNA polymorphism in 21% of the DNA fragments showing no polymorphism by CAPS. These results suggest that PCR-RF-SSCP analysis enables highly efficient DNA marker production for mapping of genes in Brassica using progeny, even progeny of closely related parents. Analysis of selfed seeds of broccoli F1 cultivars using PCR-RF-SSCP markers indicated that PCR-RF-SSCP analysis is also applicable to seed purity tests.  相似文献   
423.
面粉颗粒度是影响小麦食品加工品质的重要性状。以2001-2002年度来自北部冬麦区、黄淮冬麦区、长江中下游冬麦区和西南冬麦区的256份小麦品种(系)为材料,用激光散射颗粒度分析仪和近红外透射光谱技术对面粉颗粒度进行了研究。结果表明,我国小麦面粉颗粒度分布特点为从北向南,硬质麦分布比例逐渐减少,软质麦分布比例逐  相似文献   
424.
The Wx-D1 protein (granule-bound starch synthase) of Kanto 107, Tanikei A6099 (low amylose line), and Tanikei A6599-4 (waxy line) has been analyzed by SDS-PAGE, peptide mapping and DNA sequencing. Kanto 107 and Tanikei A6099 have the same amino acid sequences in the mature protein, but amino acid substitution (alanine to threonine) occurs at position 258 in the mature protein in Tanikei A6599-4. A comparison of deduced amino acid sequences of the mature Wx-D1 protein in these lines indicates that point mutation in the Wx-D1 gene of Tanikei A6599-4 is responsible for its waxy character.This mutant waxy wheat does not show a reduction in amylose content identicalto other waxy wheats, which probably reduces activity of the GBSS I enzyme but does not to a complete loss of activity. We discuss the function of the mutant Wx-D1 protein in starch synthesis. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
425.
Sugars are not only important energy sources and structural components, but they also act as signaling molecules that are involved in specific signal sensing. Among all ketohexose analogs (d ‐fructose, d ‐psicose, d ‐tagatose, d ‐sorbose, l ‐fructose, l ‐psicose, l ‐tagatose and l ‐sorbose), only d ‐psicose inhibited the growth of Arabidopsis roots. Phosphorylation by fructokinase occurred in d ‐fructose and d ‐psicose. d ‐Psicose‐induced inhibition was relieved by adding d ‐fructose. Thus, the inhibition could not be attributed to the toxicity of phosphorylated d ‐psicose. The phosphorylation process requires ATP. After phosphorylation, d ‐fructose is metabolized in glycolysis and becomes energy sources and structural components, whereas d ‐psicose cannot contribute to the energy sources and structural components because it does not get metabolized further. However, d ‐psicose did not affect ATP level in the Arabidopsis roots, suggesting that the d ‐psicose‐induced growth inhibition may not be related to the starvation of ATP. The phosphorylation of ketohexoses by fructokinase is known to a trigger signal‐sensing resulting in growth inhibition. Therefore, d ‐psicose can be phosphorylated by fructokinase and this process may play a possible role in signal‐sensing. This is probably one of the useful model systems for the study of the hexokinase‐independent sugar‐sensing function and for developing new types of weed‐control agents.  相似文献   
426.
为了挖掘磷高效种质资源、培育磷高效小麦品种,利用盆栽方法,设两个磷处理,以磷高效小麦品种长武134和磷低效小麦品种中国春为对照,研究了47份人工合成六倍体小麦(AABBDD)苗期的磷效率、磷吸收效率、磷利用效率的差异及评价指标。结果表明,SPAD值和地上部磷浓度不能作为评价人工合成小麦磷效率的指标,而低磷条件下幼苗的地上部干物质积累量、磷吸收效率与磷效率呈显著正相关。根据磷效率和地上部干物质积累量筛选出3份磷高效的人工合成小麦(SW23、SW24、SW26)。由本研究结果可知,粗山羊草包含与磷高效有关的基因,其与硬粒小麦杂交人工合成的小麦可作为育种材料和普通小麦杂交,进而选育磷高效小麦品种。  相似文献   
427.
Electrochemical polymerization of two different kinds of thiophene monomers on an iodine-covered gold surface created highly assembled conjugated copolymers with different electronic structures. A scanning tunneling microscope revealed images of several linkage types: diblock, triblock, and multiblock. The single strand of conjugated copolymers exhibited an anomalous swinging motion on the surface. This technique presents the possibility of understanding the copolymerization process from the different monomers on the single-molecular scale and of building single-molecule superlattices on a surface through controlled electropolymerization.  相似文献   
428.
The 18S rRNA genes of Theileria species detected in sika deer, Cervus nippon centralis in Yamaguchi and Cervus nippon yesoensis in Hokkaido, were analyzed. The percent identities of the nucleotide sequences of Theileria from Cervus nippon centralis and Cervus nippon yesoensis were more than 99%. The percent identities of the Theileria sp. from sika deer and Theileria sergenti, Theileria buffeli and Theileria cervi were 97, 96 and 95%, respectively. Phylogenetic analysis of the gene sequences also revealed that Theileria sp. detected from sika deer comprise a clade that is clearly distinct from the clade comprised of Theileria from cattle.  相似文献   
429.
In October 2007, a 15-year-old Japanese Black cow on Ishigaki Island, Okinawa, Japan, was diagnosed with Anaplasma marginale infection based on clinical symptoms, blood examination, smear observation, 16S rRNA and groEL gene sequence analysis, and the result of a CF test. The cow was introduced into the farm from mainland Japan as a calf in 1993, one year before the eradication of Rhipicephalus (Boophilus) microplus, the main vector of A. marginale in Okinawa Prefecture. It is possible that the cow was first infected with A. marginale as a calf in Ishigaki Island and had been persistently infected since then. This is the first reported clinical case of A. marginale infection of cattle since the eradication of R. microplus in Okinawa Prefecture. Additional analysis of major surface protein 1α amino acid sequences revealed that the A. marginale Okinawa strain presented four new repeat forms which were not seen in other strains. This indicates that the Okinawa strain may be a unique geographical variant of A. marginale.  相似文献   
430.
To study the behavior of histamine-producing bacteria during the processing and storage of shimesaba, we inoculated histamine-producing bacteria into raw mackerel and then evaluated bacterial counts and histamine content at each shimesaba processing step. Six histamine-producing bacteria—Morganella morganii, Enterobacter aerogenes, Raoultella planticola, Photobacterium damselae (2 strains), and Photobacterium phosphoreum—were inoculated onto the surface of mackerel fillets at various cell densities (no inoculation, 104, and 10cfu ml?1). The fillets were then treated according to the common procedure used for processing shimesaba. The concentration of NaCl in brine during the salting procedure was 10 % (w/v), and the main ingredients of the marinade broth were 27 % vinegar, 3.8 % sucrose, 0.3 % sodium glutamate, and 0.1 % sodium succinate. The level of histamine-producing bacteria and of histamine did not increase during the salting and marinating procedures. However, during the storage tests, histamine content increased remarkably in the shimesaba products stored at 10 °C for 3 days, and organoleptical degradation was also observed. However, significant deterioration, based on bacterial count, histamine content, and organoleptic evaluation, was not observed in samples stored at 5 °C. These results indicate that the use of traditional marinade broth during the processing of shimesaba and storage below 5 °C are effective methods for preventing histamine accumulation.  相似文献   
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