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1.
Kazuo Seta Mitsunori Washitake Toshio Anmo 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1980,181(3-4)
A 100-μl urine sample was chromatographed on a column packed with a strongly basic macroreticular anion-exchange resin (Diaion CDR-10, 5– μm diameter with a nominal 35% cross linkage). The elution was performed with a linear acetate gradient from 0 to 6.0 M at an average flow-rate of 0.72 ml/min and at an average pressure of 104 kg/cm2. The relative standard deviation of retention times and peak height was ± 4% or less. The properties of the macroreticular anion-exchange resin, the effect of the particle size, the pH of acetate buffers, and the effect of the flow-rate of the eluent on the separation were investigated. Thirty three components of urine were then resolved and named. 相似文献
2.
Formation of a Tree having a Low Lignin Content 总被引:2,自引:0,他引:2
Received 30 September 2001/ Accepted in revised form 26 October 2001 相似文献
3.
4.
5.
6.
Diabetic nephropathy (DN), a major cause of end-stage chronic renal failure, is histologically characterized by glomerulosclerosis. To investigate the molecular mechanisms of DN, it is important to establish a stable model of glomerulosclerosis in mice, because genomic manipulation techniques (such as gene destruction or transgene insertion) are well established in rodent species. In this study, we found that repeated administrations of streptozotocin led to early onset of glomerular sclerotic lesions in C57BL/6 mice, accompanied with renal dysfunction. During the natural course of DN, glomerular endothelial cells decreased at 10 weeks after the start of streptozotocin-injections, whereas myofibroblastic mesangial cells became evident. Our results provide an animal tool to elucidate the molecular mechanisms of DN, for example to investigate vascular pathology in diabetic glomerular diseases. 相似文献
7.
Measurement of Serine Acetyltransferase Activity in Crude Plant Extracts by a Coupled Assay System Using Cysteine Synthase 总被引:3,自引:0,他引:3
Nakamura Katsuhito; Hayama Atsushi; Masada Masahiro; Fukushima Kazuo; Tamura Goro 《Plant & cell physiology》1987,28(5):885-891
Serine acetyltransferase (SATase) (EC 2.3.1.30
[EC]
) catalyzes theformation of Oacetyl-L-serine (OAS) from L-serine in the presenceof acetyl-CoA. A novel assay method was developed for measuringthis enzyme activity in extracts from plant tissues. The assayconsists of a coupled system in which the OAS formed is convertedto cysteine by the addition of cysteine synthase (CSase) (EC4.2.99.8
[EC]
). Cysteine thus formed is determined colorimetricallyand serves as a measure for SATase activity. This method israpid, simple and sensitive, and can be readily adapted formeasurement of SATase activity in crude tissue extracts or homogenates. (Received January 14, 1987; Accepted April 27, 1987) 相似文献
8.
Modification in Cell Shape Unrelated to Cellulose Microfibril Orientation in Growing Thallus Cells of Chaetomorpha moniligera 总被引:1,自引:0,他引:1
Cellulose microfibril orientation patterns in thallus cellsof Chaetomorpha moniligera were studied, and the relationshipbetween the microfibril and the peripheral microtubule arrangementsduring cell-shape modification by colchicine was examined. Inthe cuttings from growing thalli, linearly arranged cylindricalcells developed into cask-shaped cells during 46 daysof culture at 27?C. In the cylindrical cells, microfibrils formingthe innermost portion of the wall were arranged alternatelyin longitudinal and transverse directions, but peripheral microtubuleswere always arranged only in a longitudinal direction. Thesefeatures were also noted in the cask-shaped cells. Colchicineat 103M and 3?103M accelerated both cell expansionand wall thickening with matrix deposition, but the directionsin which both microfibrils and microtubules were arranged werethe same as those of the cylindrical cells. These results indicatethat (1) the microfibril and microtubule arrangements of Chaetomorphaare not necessarily correlated, (2) changes in cell shape ofChaetomorpha are not necessarily accompanied by changes in thearrangement of cell-wall microfibrils, and (3) colchicine playsa role in the loosening and thickening of cell walls by enhancingmatrix deposition. (Received June 2, 1986; Accepted February 13, 1987) 相似文献
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10.
Tomomasa Watanabe Nobumoto Miyashita Kazuo Moriwaki Jo Hilgers 《Biochemical genetics》1987,25(3-4):239-251
Various patterns of mouse pancreatic proteinase activity bands were observed on agarose gel electrophoresis. Prt-1
a
and Prt-1
b
genes control the positive (PRT-1A) and negative (PRT-1B) expression of tryptic band V, respectively; Prt-2
a
and Prt-2
b
correspond to chymotryptic bands II (PRT-2A) and III (PRT-2B); Prt-3
a
and Prt-3
b
control the low (PRT-3A) and high (PRT-3B) tryptic activities of band IV; the Prt-1 and Prt-3 loci are closely linked on the same chromosome; Prt-6
a
and Prt-6
b
correspond to tryptic bands I (PRT-6A) and I (PRT-6B). Twenty-four laboratory strains from the United States showed the phenotype PRT-1A, PRT-3A, and PRT-2A. Of laboratory strains established in Europe, 6 showed PRT-1A, PRT-3A, and PRT-2A, and 10 had PRT-1B, PRT-3A, and PRT-2A bands. Most wild mice around the world and their descendants showed the phenotype PRT-1B, PRT-3B, and PRT-2A. Only the phenotype of M. m. brevirostris was PRT-1A, PRT-3A, and PRT-2A, which was the same as most laboratory inbred strains. PRT-2B was observed mainly in Japanese (M. m. molossinus) and Korean (M. m. yamashinai) wild mice. PRT-6B was detected only in Mus spicilegus and Mus caroli, but all other mice including wild populations and laboratory strains showed PRT-6A. New biochemical phenotypes such as PRT-2C and PRT-3C were also found in this study. 相似文献