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排序方式: 共有1104条查询结果,搜索用时 31 毫秒
31.
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
32.
H Aizawa M Kamijo Y Ohba A Mori K Okuhara H Kawasaki H Murofushi K Suzuki H Yasuda 《Biochemical and biophysical research communications》1991,179(3):1620-1626
Microtubule-associated protein-4 (MAP-4), a major MAP in proliferating cells, consists of a microtubule-binding domain and a projection domain protruding from the microtubule wall. The former contains a Pro-rich region and an assembly-promoting (AP) sequence region which is common to the neuron-specific MAPs, MAP-2 and tau1. In this paper, we describe the phosphorylation of the Pro-rich region of MAP-4 and the suppression of its assembly-promoting activity by cdc2/H1 histone kinase. This inactivation of MAP-4 may cause disassembly of the interphase microtubular network at the end of the G2 phase of the cell cycle. 相似文献
33.
H Sotokawa T Shimizu H Furuya A J Sadeque M Hatano Y Ohba M Iwaizumi Y Fujii-Kuriyama 《Biochimica et biophysica acta》1990,1037(1):122-128
Low-temperature (6-40 K) electron spin resonance (ESR) spectra of cytochrome P-450d (P-450d) and its 17 mutants have been measured. The spectra of the wild-type and all mutant P-450ds showed signals at around g = 8, 3.7 and 1.7, while they didn't show any signal at around g = 2 up to 40 K. It was thus suggested that all of these P-450ds essentially take the ferric high-spin form. The g values of the proximal mutants were closer to those of the wild-type than those of the distal and aromatic mutants, suggesting that mutations at the distal and aromatic sites influence the electronic state of the heme more profoundly than those of the proximal site. The distal multiple mutants whose distal sequences are the same as those of the low-spin type P-450s such as rat P-450c, mouse P1-450 and P3-450 showed only high-spin ESR signals. Thus the spin state of P-450ds (the wild-type and all mutants) may not be solely due to specific characteristics of the distal site, but to the unique nature of the whole heme environment of P-450d. It is also suggested that the amino acids at the distal region of P-450d may be located close to the heme, so that the water molecule cannot bind to the heme, thus taking the high-spin state. Both the aromatic mutants showed rather large deviations of the g values from those of wild-type P-450d, suggesting that the aromatic region somehow interacts with the heme. 相似文献
34.
Michio Ohba Keiko Ono Keio Aizawa Setsuo Iwanami 《Journal of invertebrate pathology》1981,38(2):184-190
Bacteriological and serological characteristics of three Bacillus thuringiensis isolates obtained in Japan were investigated. They formed typical rhomboidal parasporal inclusions but flagellar (H) antigens of these isolates were different from those of the known 17 H serotypes of B. thuringiensis. The three isolates were divided into two new serotypes (serotypes 18 and 19). The serotype 18 isolate (3–71) produced thermostable exotoxin and the inclusions of this isolate were toxic to larvae of the silkworm, Bombyx mori, but nontoxic to larvae of the mosquito, Aedes aegypti. The other isolate (119-72) belonging to serotype 18 produced inclusions nontoxic to larvae of B. mori and A. aegypti and did not produce thermostable exotoxin. However, other bacteriological properties of the isolate 119-72 were similar to those of the isolate 3–71. The serotype 19 isolate (117-72) produced inclusions nontoxic to larvae of B. mori and A. aegypti and did not produce thermostable exotoxin. Acid production from saccharose and the production of brownish purple pigment were observed in the two serotype 18 isolates, while neither of them was observed in the serotype 19 isolate. In other 29 biochemical properties tested, there was no difference among the three isolates. Based on these characteristics, the following two subspecies names are proposed: Bacillus thuringiensis subsp. kumamotoensis (serotype 18) for the type strain 3–71 and Bacillus thuringiensis subsp. tochigiensis (serotype 19) for the type strain 117-72. 相似文献
35.
Hiroko Ohba Hiroshi Inano Bun-ichi Tamaoki 《Biochemical and biophysical research communications》1981,103(4):1273-1280
Cytochromes P-450 and 5 were observed in the microsomal fraction of interstitial tissue of rat testes. Microsomal cytochrome 5 was reduced by the NADH coupled with the activities of Δ5-3β-hydroxysteroid dehydrogenase with Δ5-Δ4 isomerase through conversion of pregnenolone to progesterone. Activities of NADPH-supported 17α-hydroxylase and C-17-C-20 lyase which converted progesterone to androstenedione were stimulated by either the presence of NADH or the oxidative reaction by the dehydrogenase upon Δ5-3β-hydroxysteroids. Androstenedione production enhanced by the reaction of the dehydrogenase was decreased by addition of the antibody against NADH-cytochrome 5 reductase which was purified from rat hepatic microsomes, suggesting the active participation of cytochrome 5 in the androgen synthesis. 相似文献
36.
The reactions of 2'-O- or 3'-O-tosylated adenosines with Grignard reagents resulted in the formation of various products, which were deoxy or branched-chain deoxy sugar nucleosides, 1',2'-unsaturated nucleosides, 3'-deoxy-2'-keto sugar nucleosides, and so on. The convenient method for the synthesis of the 3'-deoxy-2'-keto adenine nucleoside is described. 相似文献
37.
24S-hydroxycholesterol (HC) is most abundant oxysterols in the brain, passes through blood brain barrier, and is therefore regarded as an intermediary for brain cholesterol elimination. We reported that large-conductance Ca2+- and voltage-activated K+ (slo1 BK) channels are suppressed by this oxysterol, which is presumably intercalated into cell membrane to access the outer surface of the channel. Such an outer approach would make it difficult to interact with the inner, ion-conducting part of the channel. The present findings showed that 24R-HC, the racemic counterpart of 24S-HC, also suppressed slo1 BK channel but in a different voltage-dependent manner. There was a difference between the effects of the two enantiomers on activation kinetics but not on deactivation kinetics. It is suggested that the chirality contributes to the efficacy of channel blockers that act from outer lipophilic parts of channels, as with those which act on the inner, ion-permeable surface. 相似文献
38.
Etsuko Kawashima Yasuhiro Nakanishi Yusuke Terui Hideyuki Tomitori Keiko Kashiwagi Yusuke Ohba 《Nucleosides, nucleotides & nucleic acids》2013,32(4):196-205
Pyrrole polyamide-2′-deoxyguanosine 5′-phosphate hybrid (Hybrid 4) was synthesized and evaluated in terms of the inhibition of mouse mammary carcinoma FM3A cell growth. Hybrid 4 was found to exhibit dose-dependent inhibition of cell growth. 相似文献
39.
Hideaki Ohba 《Curtis's Botanical Magazine》2013,30(3):158-165
Pinus amamiana Koidz., an endangered pine from Yakushima and Tanegashima, is illustrated and described. Threats to its survival are discussed. 相似文献
40.
Masaaki Konishi Seigo Sugiyama Koichi Sugamura Toshimitsu Nozaki Keisuke Ohba Junichi Matsubara Kenji Sakamoto Yasuhiro Nagayoshi Hitoshi Sumida Eiichi Akiyama Yasushi Matsuzawa Kentaro Sakamaki Satoshi Morita Kazuo Kimura Satoshi Umemura Hisao Ogawa 《PloS one》2013,8(4)