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排序方式: 共有2273条查询结果,搜索用时 15 毫秒
21.
Satoru Ohba Kiyoshi Kidouchi Toshiyuki Katoh 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1991,568(2)
A column-switching high-performance liquid chromatographic method, requiring no sample preparation apart from filtration, is described for quantification of urinary orotic acid, uracil and pseudouridine. The analyses were carried out using a reversed-phase octadecylsilane-bonded column for sample clean-up and a cation-exchange column for separation; 5–20 ]sml samples of urine were directly analysed, and more than 100 samples could be analysed consecutively. Each sample required only 30 min. Detection limits of these compounds were 5 pmol. Creatinine-related urinary uracil excretion was lowest in the newborn period (17.3 ± 14.4 μmol/g of creatinine). A patient with partial ornithine transcarbamylase deficiency and his mother usually excreted a high level of uracil during the period of normal orotic acid excretion and normal serum ammonia level. 相似文献
22.
2,2,2-trichloroethyl 3,6-di-O-benzyl-2-deoxy-2-phthalimido-β-d-glucopyranoside (9) was synthesized in 6 steps from the readily available 1,3,4,6-tetra-O-acetyl-2-deoxy-2-phthalimido-β-d-glucopyranose in 25% overall yield by employing the stannyl method for the regioselective activation of hydroxyl groups. Dibenzyl ether 9 was then glycosylated with appropriate glycosyl donors to afford lactosamine and chitobiose derivatives in good yield. 相似文献
23.
A lactosaminyl donor, 3,6-di-O-acetyl-2-deoxy-2-phthalimido-4-O-(2,3,4,6-tetra-O-acetyl-β-d-galactopyranosyl)-β-d- glucopyranosyl chloride, was synthesized in 10 steps, starting from 1,3,4,6-tetra-O-acetyl-2-deoxy-2-phthalimido-β-d-glucopyranose. Benzyl 3,6-di-O-benzyl-2-deoxy-2-phthalimido-β-d-glucopyranoside was prepared by regioselective benzylation at the primary hydroxyl group by the stannyl method, and was used as a key intermediate. 相似文献
24.
25.
Disappearance of Ca2+-induced phase separation in phosphatidylserine-phosphatidylcholine membranes has been studied under several conditions by monitoring electron spin resonance spectrum of spin-labeled phosphatidylcholine. The membranes were prepared in Millipore filters. Electron micrographs of the preparations showed formation of multilayered structures lined on the pore surface. The phase separation was disappeared when the membrane was soaked in non-buffered salt solution (100 ml KCl, pH 5.5). It was markedly contrasting that when the bathing salt solution was buffered no disappearance was observed. Disappearance of the phase separation was also observed when the Ca2+-treated membrane was transferred to acidic salt solutions () or to low ionic strength media () buffered at pH 5.5, and then to the buffered salt solution (100 mM KCl, pH 5.5). These are due to replacement of Ca2+ by proton, proton-induced separation, followed by disappearance of the phase separation inthe buffered salt solution. Biological significance of the competition between Ca2+ and proton for the phase separation or domain formation in the membranes was emphasized. 相似文献
26.
Summary A method has been established for the dual staining of complex carbohydrates in light microscopy. It is a combined concanavalin A-peroxidase-diaminobenzidine (Con A-PO-DAB)-alcian blue (AB) (pH 2.5) method, and with this method it is possible to color -D-glucosyl and -D-mannosyl residues and acidic groupings of complex carbohydrates in tissues brown and blue respectively. Histochemical experiments using histological sections with reactive complex carbohydrates and casein films containing carbohydrates of known chemical structure have substantiated the validity of the above significance of the dual staining. Thus, the present dual staining method is a reliable one and a new addition to a series of dual staining techniques hitherto employed in the light microscopic histochemistry of complex carbohydrates.This investigation was supported in part by a Grant-in-Aid from the Japanese Education Ministry (1975) 相似文献
27.
Keishi Abe Yoichi Otsuka Minoru Yasujima Satoru Ciba Masahide Seino Nobuo Irokawa Kaoru Yoshinaga Fumio Hirata Shiro Ohki Nobuhiko Nakazawa Toshio Hanyu 《Prostaglandins & other lipid mediators》1976,12(5):843-848
The excretion rates of main urinary metabolite of PG F2α were measured radioimmunologically in 4 healthy persons and in 13 essential hypertensives. The resting values were 9.3±0.73 in the former and 10.4±2.17 ng/min in the latter. There was no significant differences between them. The excretion of the metabolite decresed prominently after the administration of furosemide. The percent decrease was 57% in healthy persons and 70% in essential hypertension. The percent result supports that furosemide inhibit the catabolism of PG F2α. 相似文献
28.
Functional redundancy of multiple forest taxa along an elevational gradient: predicting the consequences of non‐random species loss 下载免费PDF全文
Akira S. Mori Takayuki Shiono Takashi F. Haraguchi Aino T. Ota Dai Koide Takayuki Ohgue Ryo Kitagawa Ryo Maeshiro Toe Toe Aung Taizo Nakamori Yusuke Hagiwara Shunsuke Matsuoka Anzu Ikeda Takuo Hishi Satoru Hobara Eri Mizumachi Andreas Frisch Göran Thor Saori Fujii Takashi Osono Lena Gustafsson 《Journal of Biogeography》2015,42(8):1383-1396
29.
Satoru Masuda Shigefumi Kuwahara Toshio Suguro Kenji Mori 《Bioscience, biotechnology, and biochemistry》2013,77(11):2515-2520
The (S)-enantiomer of the sex pheromone of the yellow scale (Aonidiella citrina), (S,E)-6-isopropyl-3,9-dimethyl-5,8-decadienyl acetate, was stereoselectively synthesized from (R)-(+)-citronellic acid. 相似文献
30.