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51.
Fujino K Yanase E Shinoda Y Nakatsuka S 《Bioscience, biotechnology, and biochemistry》2004,68(3):764-766
The reactivity of N-tosylindole (4) in the presence of aluminum chloride was studied, and two types of oligomerization of 4 were observed. One type was condensation between both pyrrole parts (dimers 5 and 6 and trimer 7) and the other was between a pyrrole part and a benzene part of each indole nucleus (dimers 8 and 9). 相似文献
52.
Biological characteristics of cultured cells derived from various types of human brain tumors 总被引:2,自引:0,他引:2
Ishiwata I Ishiwata C Iguchi M Soma M Sato Y Sonobe M Kiguchi K Tachibana T Ishikawa H 《Human cell》2004,17(3):117-124
We placed in culture brain tumors from 45 cases (7 cases of astrocytoma, 2 from oligodendrogliomas, 2 glioblastomas, 2 ependymomas, 13 meningiomas, 6 pituitary adenomas, 5 neurinomas, a malignant lymphoma, a choroid plexus papilloma, and 6 metastatic tumors) and succeeded in making a primary culture from 33, and maintained 17 in vitro over a considerable period of time (greater than three months). In the early period of the primary cultures, the astrocytoma cells had cytoplasmic processes which contacted each other, the oligodendroglioma cells were small and spindle-shaped, the glioblastoma cells were neoplastic with pleopmorphic features and possessed cytoplasmic processes, the ependymoma cells formed a rosette-like cell arrangement, the meningioma cells were spindle- or round-shaped cells and characterized as forming psammoma bodies, the pituitary adenoma cells were round- or oval-shaped cells and produced growth hormone (GH), adenocorticoid tropic hormone (ACTH), prolactin, or other hypophyseal hormones, the choroid plexus papilloma cells were round-or polygonal and showed a papillary cell arrangement, the neurinoma cells were spindle- or fibrous-shaped cells, and the malignant lymphoma cells were round and formed cell aggregates floating in the culture medium. 相似文献
53.
Yasuda S Wu PS Hattori E Tachibana H Yamada K 《Bioscience, biotechnology, and biochemistry》2004,68(1):51-58
A method for simultaneous detection and quantification is presented to determine the presence of isoflavones and bisphenol A in a biological sample. A coulometric array detector was used with reversed-phase high-performance liquid chromatography (HPLC). Daidzein (1), glycitein (2), genistein (3) and their glucoside conjugates, daidzin (4), glycitin (5) and genistin (6), were measured as phytochemicals. Also assayed here was equol (7), a metabolite from compound 1, and bisphenol A (8), an industrial chemical that acts as an endocrine disrupter. All chemicals were simultaneously detected by using a 600-mV single detection voltage with high efficacy. A mixture of 1, 3 and 8 was orally administered to rats, and the levels of these three chemicals in the serum were clearly increased after a 4 kU beta-glucuronidase treatment. The levels of compounds 1 and 3 in the serum were detected at 1665 and 2040 ng/ml, while 8 was at a low level of 417 ng/ml. Compound 7 in the serum was not detected until after enzymatic hydrolysis (72 ng/ml). These results suggest that this analytical method would be useful for metabolic and pharmacokinetic studies on isoflavones and bisphenol A. 相似文献
54.
Effects of soybean beta-conglycinin on hepatic lipid metabolism and fecal lipid excretion in normal adult rats 总被引:1,自引:0,他引:1
Fukui K Kojima M Tachibana N Kohno M Takamatsu K Hirotsuka M Kito M 《Bioscience, biotechnology, and biochemistry》2004,68(5):1153-1155
beta-Conglycinin decreased blood triacylglycerol (TAG) levels in male Wistar adult rats. Liver mitochondrial carnitine palmitoyltransferase activity in the beta-conglycinin-fed group significantly increased as against the casein-fed group. Hepatic fatty acid synthase activity in the beta-conglycinin group significantly decreased as against that of the casein-fed group. Fecal fatty acid excretion in the beta-conglycinin group was significantly higher than in the casein group. 相似文献
55.
Shibata N Suto K Ichimura E Yoshimura K Muneo K Tomigami S Morimoto Y Ogata M Yagi T Higuchi Y Yasuoka N 《Protein and peptide letters》2004,11(1):93-96
Hexadecaheme high molecular weight cytochrome c from a sulfate-reducing bacterium, Desulfovibrio vulgaris Miyazaki F has been successfully purified and crystallized. X-ray diffraction data have been collected by the multiple wavelength anomalous dispersion method. The crystal belongs to the space group P2(1)2(1)2(1) with unit-cell parameters a=60.42, b=84.29 and c=144.16 A and contains one molecule per asymmetric unit. 相似文献
56.
57.
Ide T Takahashi Y Kushiro M Tachibana M Matsushima Y 《The Journal of nutritional biochemistry》2004,15(3):169-178
N-3 fatty acids exert a potent serum lipid-lowering effect in rodents mainly by affecting hepatic fatty acid oxidation and synthesis. However, it has been observed that fish oil and docosahexaenoic acid ethyl ester do not lower serum lipid levels in apolipoprotein E (apoE)-knockout (Apoetm1Unc) mice generated by gene targeting. To test the hypothesis that apoE expression is required for n-3 fatty acid-dependent regulation of serum lipid levels and hepatic fatty acid metabolism, we examined the effect of fish oil and n-3 fatty acid ethyl esters on the activity and gene expression of hepatic enzymes involved in fatty acid oxidation and synthesis using an alternative apoE-deficient mouse model with the BALB/c genetic background (BALB/c.KOR-Apoeshl). ApoE-deficient mice were fed diets containing 9.4% palm oil, fish oil, or 5.4% palm oil and 1% EPA plus 3% DHA ethyl esters for 15 days. In contrast to the reported data on apoE-knockout mice, fish oil and n-3 fatty acid ethyl esters greatly decreased serum triacylglycerol, cholesterol, and phospholipid levels in the Apoeshl mice. The decreases were greater with fish oil than with ethyl esters. The alterations by dietary n-3 fatty acids of serum lipid levels were accompanied by parallel changes in the activity and mRNA levels of enzymes involved in hepatic fatty acid oxidation and synthesis. The reason for the discrepancy between the results of the current study and previous studies is unknown. However, our study at least indicates that a lack of apoE expression does not necessarily accompany deficits in the n-3 fatty acid-dependent regulation of serum lipid levels and hepatic fatty acid metabolism. 相似文献
58.
Multiple targeted gene replacements are often required for functional analyses of cyanobacterial genomes. For this purpose, we previously devised a simple genetic method, termed rps12-mediated gene replacement, in a cyanobacterium Synechococcus elongatus PCC 7942 for construction of mutants free from drug resistance markers. Here, we improved the method by employing a heterologous rps12 gene encoding a ribosomal protein S12 from Synechocystis sp. PCC 6803. Dominant streptomycin-sensitive phenotype of the Synechocystis rps12 gene was manifested only when it was expressed under the strong promoter of psbAI gene in S. elongatus PCC 7942 bearing a streptomycin-resistant rps12 allele. Transformation of the rps12 heteroallelic strains with non-replicating template plasmids permitted the selection of recombinants with gene replacement at frequencies up to 50% among streptomycin-resistant progeny. 相似文献
59.
Tachibana T Hirofuji K Matsumoto M Furuse M Hasegawa S Yoshizawa F Sugahara K 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2004,137(1):183-188
The present study was carried out to investigate whether the hypothalamus is involved in the anorexic effect of glucagon-like peptide-1 (GLP-1) in chicks. To examine this, Fos expression in the chick hypothalamus were immunohistochemically detected after intracerebroventricular (ICV) injection of 30-pmol GLP-1. ICV injection of GLP-1 stimulated the expression of Fos-like immunoreactive (FLI) cells in the ventromedial hypothalamic nucleus (VMN). When 15-pmol GLP-1 was directly injected into the chick VMN, the chick's food intake was significantly decreased compared with the control treatment. Microinjection of GLP-1 into the (LHA) also inhibited feeding in chicks, although ICV injection of GLP-1 did not stimulate FLI expression in the brain area. These results suggest that VMN and some brain regions are involved in the anorexic effect of GLP-1 in chicks. 相似文献
60.
Electromyographic analysis of walking in water in healthy humans 总被引:2,自引:0,他引:2
Masumoto K Takasugi S Hotta N Fujishima K Iwamoto Y 《Journal of PHYSIOLOGICAL ANTHROPOLOGY and Applied Human Science》2004,23(4):119-127
This study was designed to describe and clarify muscle activities which occur while walking in water. Surface electromyography (EMG) was used to evaluate muscle activities in six healthy subjects (mean age, 23.3 +/- 1.4 years) while they walked on a treadmill in water (with or without a water current) immersed to the level of the xiphoid process, and while they walked on a treadmill on dry land. The trials in water utilized the Flowmill which has a treadmill at the base of a water flume. Integrated EMG analysis was conducted for the quantification of muscle activities. In order to calculate the %MVC, the measurement of maximal voluntary contraction (MVC) of each muscle was made before the gait analysis, thus facilitating a comparison of muscle activities while walking in water with those on dry land. The %MVCs obtained from each of the tested muscles while walking in water, both with and without a water current, were all found to be lower than those obtained while walking on dry land at a level of heart rate response similar to that used when walking on dry land. Furthermore, the %MVCs while walking in water with a water current tended to be greater when compared to those while walking in water without a water current. In conclusion, the present study demonstrated that muscle activities while walking in water were significantly decreased when compared to muscle activities while walking on dry land, that muscle activities while walking in water tended to be greater with a water current than without, and that the magnitude of the muscle activity in water was relatively small in healthy humans. This information is important to design water-based exercise programs that can be safely applied for rehabilitative and recreational purposes. 相似文献