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241.
242.
Direct evidence on the functions of root-cap mucilage during plant root growth in soil is limited mainly due to the lack of a method for in situ measurements. In this paper, we offer a method that facilitates the measurement of mucilage exudation when roots are growing in soil. We observed the mucilage exudation directly through a transparent panel located on the side of a root box in which plant roots were growing. We used a CCD camera attached to a microscope to observe and record mucilage exudation. Using image analysis, the activity of mucilage exudation was evaluated based on the area occupied by the mucilage on the root tip. The area of mucilage observed on the root tips after 1-h growth in soil corresponded with the weight of mucilage that was originally observed on the tips before they were transplanted. This relationship suggests that the observed area on root tip relates to total exudation. The area of mucilage exudation on the root tips was high (0.48 mm2) at night and low (0.35 mm2) at midday, suggesting that the activity of mucilage exudation follows diurnal changes. Furthermore, the mucilage exudation positively correlated with the root elongation rate, implying that fast-growing roots exude more mucilage. 相似文献
243.
Y Kitade T Makino R Nakanishi M Sako K Hirota Y Maki 《Nucleic acids symposium series》1991,(25):59-60
Oxidative cyclization of 2',3'-O-isopropylideneadenosines to the corresponding 5'-O,8-cyclo-2',3'-O-isopropylideneadenosines was achieved by using by lead tetraacetate, cupric chloride, and N-halogeno-succinimide as an oxidant, and by irradiation with a uv-visible light in the presence of pyrimido[5,4-g]pteridinetetrone 5-oxide. The reaction modes for the oxidative cyclization were investigated and discussed. In particular, N6-substituent effects on the oxidative cyclization provided a positive proof supporting the respective reaction mode. 相似文献
244.
Y Sako M Asada S Kubota C Sugimoto M Onuma 《International journal for parasitology》1999,29(4):593-599
The cDNA encoding a 23-kDa piroplasm membrane protein (p23) of Theileria sergenti Chitose (C)-type was isolated and its nucleotide sequence was determined. The gene encodes a polypeptide of 223 aa with a 28 residue N-terminal signal sequence and a hydrophobic, valine-rich, C-terminal transmembrane domain, as deduced from its nucleotide sequence. Southern blot hybridisation analysis proved that p23 gene was a single copy gene and had allelic forms of the gene in the parasite population. By PCR, the open reading frames of T. sergenti Ikeda (I)-type and Theileria buffeli (B)-type p23 were amplified from genomic DNA and their nucleotide sequences were also determined. Comparison of C-type sequence with that of I-type and B-type revealed 90.5% and 93.5% sequence similarity, respectively, at the aa level. These results suggest that a conserved molecule in these benign Theileria spp. could be a candidate antigen for the development of an anti-piroplasm vaccine. 相似文献
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A new double immunohistochemical technique for the simultaneous detection of B-cells and T-cells was investigated, using tissue preparations obtained from human axillary lymph nodes and rejected renal allografts. The specimens were immunostained first for the demonstration of B-cells, by the immunogold-silver staining (IGSS) method using Leu-12 monoclonal antibody, and then for T-cells by the avidin-biotin-peroxidase complex (ABC) method using Leu-1 monoclonal antibody. With the present methods, both B-cells and T-cells were clearly detected and distinctively identified without cross-linking of antibodies or double reaction of enzymes. 相似文献
248.
K Tanaka A Sugawara M Sakamoto T Inoue A Yawata O Koshimura Y Sako S Sasaki A Shimatsu H Nakamura 《Endocrinologia japonica》1992,39(6):533-538
A familial case of generalized resistance to thyroid hormone (GRTH) is described. A 17-year-old man (case 1), who had been treated with methimazole under the diagnosis of Graves' disease and his 11-year old sister (case 2) visited our clinic for the evaluation of their thyroid function. They lacked the signs and symptoms of thyrotoxicosis in spite of extremely high serum thyroid hormone levels. Their plasma TSH levels were not suppressed, but in fact markedly increased after TRH loading. Their peripheral indices of thyroid hormone were within normal limits and were not influenced by exogenous T3 administration. Even 150 micrograms T3 administration for 7 days did not fully suppress the TRH-stimulated TSH level in case 2. The two patients thus were diagnosed to have GRTH. Sera from their father and another sister showed identical abnormalities. 相似文献
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250.
Acidic glycosphingolipids including two sulfatides and five gangliosides were isolated from porcine plasma. They were characterized by NMR spectrometry as galactosylceramide-I3-sulfate and lactosylceramide-II3-sulfate, gangliosides GM3, GD3, GM1, GD1a and fucosyl GM1. 相似文献