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排序方式: 共有103条查询结果,搜索用时 31 毫秒
91.
It has been suggested that plasma membrane (PM) lipids play a major role in aluminum (Al) tolerance; however, no direct investigations have been carried out using PM lipids from root-tips. Here we report a new technique for PM isolation as an alternative to the laborious two-polymer phase partitioning method that is commonly applied, as follows: 1) separation of protoplasts from 1-cm root-tip portions by enzymatic digestion, 2) attachment of the purified protoplasts to glass plates coated with polylysine, 3) preparation of PM ghosts by successive burst of the attached protoplasts using three separate buffer solutions (25 mM PIPES, 5 mM EDTA, and 2 mM MgCl2, at pH 7.0) with slow stirring for 60 s. The PMs were confirmed to be devoid of organelle membranes by fluorescence microscopy, thin layer chromatography (TLC) and western blot analysis. The PM lipids obtained were found to be useful for studies on their differential permeability and lipid composition between lines of triticale or cultivars of maize under Al stress.  相似文献   
92.
Rime-ice and snow samples were collected at mountain sites in Kyushu, Japan during the winter of 1994, and both soluble and insoluble substances in the melted rime-ice were analyzed by ion chromatography, inductively coupled plasma-mass spectrometry (ICP/MS) and analytical electron microscopy, in order to find the evidences of long-range transport of air pollutants from the cities of the East Asian region. The relationships between Al, which is most often used as an index of soil components, and other elements were examined. The positive correlation was found between Al and three elements (Ti, Mn, Ba). Therefore, behaviors of these elements in rime-ice may be similar to that of soil particles. Furthermore, it was possible to classify the elements into three groups with the relation between a lead isotope ratio and concentration ratio of lead and zinc (Pb/Zn). In addition, numbers of particles were found in the rime-ice. The particles around 1 m in diameter were considered to be the combustion products of coal, whose Pb/Zn were similar to that of previous survey report in Korea. The existent forms of chemical species in rime-ice will become an important factor, when we consider the origin of air pollutants transported over long distances in the East Asian region.  相似文献   
93.
An adult male white eared-pheasant (Crossoptilon crossoptilon) at a Japanese zoo exhibited lethargy and emaciation. Microscopic examination of a blood smear revealed a haemosporidian parasitic infection. Based on the morphological characteristics and molecular analysis of the parasite, it was identified as Plasmodium (Bennettinia) juxtanucleare. This is the first report of P. juxtanucleare infection in bird species belonging to the genus Crossoptilon. Caution against avian malaria infection is required for the conservation of endangered bird species in zoos.  相似文献   
94.
95.
ABSTRACT

Reducing the arsenic (As) concentration in rice grains is of great interest from a human health perspective. Iron (Fe) materials immobilize As in soils, thereby effectively reducing the As concentration in rice grains. We investigated the effect of by-product Fe materials obtained from the casting industry on the As mobility in two soils (soil A and soil B) by a long-term (approximately 100 days) flooded soil incubation experiment. The examined Fe materials were spent steel shot (SSS), fine spent casting sand (SCS) containing steel shot, and two kinds of residual Fe materials (RIMs) from steel shot production. Commercial Fe materials used to immobilize As (zero-valent Fe and ferrihydrite) were tested for comparison. The dissolved As in soil solution of controls for soil A and soil B reached approximately 100 and 800 μg L?1, respectively. The effect on As immobilization of all the by-product Fe materials increased with time and was comparable to or greater than that of commercial ferrihydrite, except for SCS. The additions of SSS and RIMs decreased by more than 90% of the dissolved As in soil A and decreased by more than 50% in soil B after 100 days incubation. Overall, the effect of the by-product Fe materials on the solubility of silicon and phosphorus was much less than that of the commercial Fe materials. Considering the cost advantage over commercial Fe materials, the Fe materials obtained from the casting industry as by-products are promising amendments for the immobilization of As in paddy soils.  相似文献   
96.
The aim was to characterize the changes of plasma component concentrations after feeding in Japanese Black (B) and Japanese Shorthorn (S) cattle. Eight females, five B and three S, with a mean bodyweight (standard deviation) of 282.0 (20.3) kg were selected and supplied with only water for 28 h after feeding. Blood was taken from the jugular vein at 4‐h intervals for 32 h after feeding. Metabolite (cholesterol, CL; glucose, GLU; nonesterified fatty acid, NEFA; triacylglycerol, TG; total protein, TP) and insulin‐like growth factor‐1 (IGF‐1) concentrations in plasma were measured. In both breeds GLU tended to decrease linearly with a similar slope. Differences between the initial mean NEFA at 4 h after feeding (Start) and that at 24 h after the start (End) were significant in both breeds, but S increased significantly more than B at and after 8 h from the Start. The TG in S tended to change more than in B, and CL and IGF‐1 in both breeds changed continuously at similar levels. The TP in B tended to decrease more slowly and be lower than S. The change in NEFA, especially, suggests that nutritional status sensitively reflects genetic background.  相似文献   
97.
This study was conducted to evaluate immunological changes in peripheral blood leukocytes in pigs that were genetically selected for their improved resistance to mycoplasmal pneumonia of swine (MPS), using MPS vaccine as an antigen. Twelve castrated MPS‐selected Landrace pigs were compared with the same number of pigs from a nonselected line by using a time‐course analysis at the hematological level. After the second sensitization with MPS vaccine, the percentages of B cells, CD4+ T cells, and natural killer (NK) cells in total leukocytes were lower in the selected line than in the nonselected line, whereas the percentage of granulocytes in total leukocytes increased in the MPS‐selected line. We also assessed the proliferative ability of peripheral blood mononuclear cells (PBMCs) stimulated with Mycoplasma hyopneumoniae, lipopolysaccharide or concanavalin A, and found that although the proliferative ability of the PBMC was not different between the two lines at a steady state, the nonselected line showed a significantly higher proliferative ability after sensitization with MPS vaccine than the selected line regardless of antigens used. These results thus indicate that the selection of pigs on the basis of MPS resistance changes their immunophenotype, and would give us beneficial information for the prevention of MPS infection.  相似文献   
98.
利用ISSR分子标记进行不同来源大豆品种的分类   总被引:4,自引:0,他引:4  
谢甫绨 《大豆科学》2005,24(3):161-165
采用ISSR分子标记技术对不同来源大豆品种(系)进行了分类研究,对UBC ISSR801-850引物进行筛选,发现有11个引物没有产物,选出39个引物具有扩增产物,一般每个引物可以扩增出1-6条带,产物片段大小多在831-3530b之间.39个引物共扩增出121条带,其中多肽性带47条,占38.84%.每个引物平均可扩增出带数为3.1条;其中多肽性带数为1.21条.ISSR引物扩增的结果表明,ISSR分子标记技术能很好地用来区分不同来源的大豆品种(系).不同大豆品种(系)因其遗传背景不同,经ISSR引物扩增出来的谱带数也不一样,而且不同品种(系)还具有特异性的标记谱带.另外,对沈农系列大豆品种(系)的生产力与本试验采用的日本大豆品种的比较分析可以看出,沈农系列大豆品种(系)的生产力要高于日本大豆品种的生产力.  相似文献   
99.
不同基因型对白菜子叶培养不定芽再生的影响   总被引:7,自引:0,他引:7  
探讨了基因型对白菜子叶培养不定芽再生的影响。结果表明,不同基因型的不定芽再生率和平均每子叶生芽数差异极大,在被检索的123个大白菜和20个小白菜品种中,芽再生率为0-97.5%,平均每子味生芽数为1.0-10.7个。17个大白菜和5个小白菜品种的不定芽再生率在80%以上。芽再生率与品种起源地、结球类型及熟性无相关。  相似文献   
100.
Various types of malt quality profiles have been investigated to benefit the North American brewing industry. Herein, we report the development and brewing quality of the hulled, two-row malting barley (Hordeum vulgare L.) variety ‘CDC Goldstar’ lacking lipoxygenase-1 (LOX-1-less). This new variety offers a novel malt type for the improvement of beer flavor stability. The agronomic performance of ‘CDC Goldstar’ was tested in the Western Cooperative Two Row Barley Registration Trials during 2013–2014. In addition to high lodging tolerance, the new variety showed 6% higher yield than the current leading variety ‘CDC Copeland’. The malt quality of ‘CDC Goldstar’ showed higher diastatic power and lower wort β-glucan content than ‘CDC Copeland’ and controllable proteolytic modification (soluble nitrogen and Kolbach Index). Pilot- (100 L) and commercial-scale (5,000 L) brewing trials were conducted using ‘CDC PlatinumStar’, another LOX-1-less variety with a low enzymatic profile, as the control variety. Absence of the LOX-1 trait from ‘CDC Goldstar’ maintained trans-2-nonenal levels in aged beers as low as those in other LOX-1-less varieties without affecting major beer parameters, such as ester and aldehyde content or foam stability. The newly developed ‘CDC Goldstar’ malting barley provides added value for the beer industry and consumers.  相似文献   
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