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排序方式: 共有424条查询结果,搜索用时 15 毫秒
1.
Immunohistochemical localization of Na+-dependent glucose transporter in rat jejunum 总被引:2,自引:0,他引:2
Kuniaki Takata Toshiko Kasahara Michihiro Kasahara Osamu Ezaki Hiroshi Hirano 《Cell and tissue research》1992,267(1):3-9
Summary Glucose is actively absorbed via a Na+-dependent active glucose transporter (Na-GT) in the small intestine. We raised a polyclonal antibody against the peptide corresponding to amino acids 564–575 of rabbit intestinal Na-GT, and localized it immunohistochemically in the rat jejunum. By means of immunofluorescence staining, Na-GT was located at the brush border of the absorptive epithelial cells of the intestinal villi. Electron-microscopic examination showed that Na-GT was localized at the plasma membrane of the apical microvilli of these cells. Little Na-GT was found at the basolateral plasma membrane. Along the crypt-villus axis, all of the absorptive epithelial cells in the villus were positive for Na-GT. In addition to the brush border staining, the supranuclear positive staining, which was shown to be the Golgi apparatus by use of electron microscopy, was seen in cells located between the base to the middle of the villus. Cells in crypts exhibited little or no staining for Na-GT. Goblet cells scattered in the intestinal epithelium were negative for Na-GT staining. These observations show that Na-GT is specific to the apical plasma membrane of the absorptive epithelial cells, and that the onset of Na-GT synthesis may occur near the crypt-villus junction. 相似文献
2.
Summary From a detailed complementation analysis of the region II che mutants of Salmonella typhimurium, we have located five che genes, cheA, cheW, cheR, cheB, and cheY. We have shown that corrections are required in the previous assignment of the mutations in four strains: both SL2514 and SL2515 which have been reported to be cheY mutants are cheR mutants, SL2539 is not a cheA but a cheW mutant, and ST171 which has been reported to be a cheZ mutant is a double mutant with defects in both cheA and cheB. Since ST171 is the only cheZ mutant so far isolated, the idea that the cheZ gene might play an essential role in chemotaxis in S. typhimurium as in Escherichia coli has lost its experimental basis. Furthermore, a number of deletion mutants in region II resulting from the excision of Tn10 have been isolated and analysed. From these experiments, we propose that the gene order in region II is flaK-flaE-motA-motB-cheA-cheW-cheR-cheB-cheY-flaM-flaC, which is identical with that in E. coli. 相似文献
3.
Genetic analysis of three additional fla genes in Salmonella typhimurium 总被引:16,自引:0,他引:16
S Yamaguchi H Fujita T Taira K Kutsukake M Homma T Iino 《Journal of general microbiology》1984,130(12):3339-3342
In Salmonella typhimurium, 27 fla genes responsible for formation of flagella have been identified and assigned to three regions on the genetic map, termed fla regions I to III. By genetic analysis of 1984 non-flagellate mutants obtained from a phase-1 stable strain of S. typhimurium, SJW1103, three additional fla genes were identified; one, termed flaW, was assigned to fla region I and the other two, termed flaV and flaX, to fla region III. By intergeneric complementation tests, the flaW, flaV and flaX genes were shown to be functionally homologous with flaS, flbC and flaP of Escherichia coli, respectively. Electron microscopy showed that flaW and flaV mutants carried hook-basal body structures. 相似文献
4.
The distribution density of opioid receptors in the brain of El mice (seizure-susceptible strain) was examined to determine the relation between seizures and the opioid system. Saturation curves and Scatchard plots of [3H]2-d-alamine-5-d-leucine enkephalin binding revealed that the opioid delta receptor density in adult El mice during interictal periods was significantly increased in the cerebral cortex, hippocampus, and septal area. It was further shown that the concentration of such receptors in 25-day-old El mice that had no seizures was also significantly increased in the hippocampus and septal area, with no changes in apparent affinities, as compared with in the corresponding regions in ddY mice (seizure-nonsusceptible strain; the mother strain of El). Such up-regulation of opioid receptors in the El mouse brain could result from deficits in endogenous opioid peptides, which could be associated with the pathogenesis of seizure diathesis in the El mouse. 相似文献
5.
Furukawa Toshiko; Koga Jinichiro; Adachi Takashi; Kishi Kunihei; Syono Kunihiko 《Plant & cell physiology》1996,37(7):899-905
In a study of various phytopathogenic fungi, we found that fungithat belong to the genus Rhizoctonia produce IAA efficientlyfrom tryptophan. R. solani Kühn MAFF-305219, in particular,produced large amounts of tryptophol (Tol), which was assumedto be a specific by-product of the indole-3-pyruvate (IPy) pathway,in addition to IAA. Therefore, this fungus seemed suitable foranalysis of the function and the regulation of the biosynthesisof auxin by a fungal pathogen. Under normal aerobic conditions,the ratio of IAA to Tol synthesized by this strain was higherthan that under less aerobic conditions. In metabolic studieswith various indole derivatives, R. solani converted L-tryptophanand indole-3-acetaldehyde to IAA and Tol, but other indole derivativeswere scarcely metabolized. These results suggest that both IAAand Tol are synthesized from tryptophan through the IPy pathwayin Rhizoctonia. (Received May 27, 1996; Accepted July 8, 1996) 相似文献
6.
Expression of NADH-Dependent Glutamate Synthase in Response to the Supply of Nitrogen in Rice Cells in Suspension Culture 总被引:2,自引:0,他引:2
Watanabe Sachiko; Sakai Takahiro; Goto Satoshi; Yaginuma Toshiko; Hayakawa Toshihiko; Yamaya Tomoyuki 《Plant & cell physiology》1996,37(7):1034-1037
The effects of inorganic and organic nitrogen on the levelsof mRNA for NADH-dependent glutamate synthase (GOGAT) and theprotein were examined in rice cells in suspension culture. Asupply of NH+4, NO-3, glutamine, or asparagine induced the accumulationof the protein and mRNA, but levels of mRNA for ferredoxin-GOGATwere hardly affected.
1Present address: P.C. Center Wakuya-cho, Toda-gun, Miyagi,Japan. 相似文献
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9.
Toshiko Yamamoto Saburo Yamamoto Tetsuro Kataoka Tohru Tokunaga 《Microbiology and immunology》1994,38(10):831-836
A synthetic 22-mer oligodeoxyribonucleotide having an AACGTT palindrome, AAC-22, induced interferon (IFN) production and augmented the natural killer (NK) activity in murine splenocytes, whereas its analogue, ACC-22, having an ACCGGT palindrome, did not. The binding of AAC-22 to splenocytes was not different from that of ACC-22. Lipofection of AAC-22 to splenocytes remarkably enhanced IFN production and NK cell activity, whereas that of ACC-22 caused little enhancement. These results strongly suggest that the prerequisite for IFN production is not the binding of AAC-22 to the cell surface receptors, but its penetration into the spleen cells. 相似文献
10.
Masafumi Tomita Toshiko Okuyama Shoichi Sato Hideo Ishizu 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1993,621(2)
We applied micellar electrokinetic capillary chromatography to simultaneous separation and determination of nitrazepam and its major metabolites, 7-aminonitrazepam and 7-acetamidonitrazepam, in spiked urine. Prior to electrophoresis, the three compounds were successfully extracted from the spiked urine with commercial disposable solid-phase cartridges. The optimum running buffer for the separation was prepared by combining 85 parts of 60 mM sodium dodecyl sulphate—6 mM phosphate—borate, adjusted to pH 8.5, with 15 parts of methanol. The separation order, completed within 25 min, was 7-aminonitrazepam > 7-acetamidonitrazepam > nitrazepam, at an applied potential of 20 kV. We obtained reproducible electropherograms in successive repetitions, and few other peaks or interferences appeared in the electropherogram. The detection limits of the three compounds were 50–100 pg (0.1–0.2 μg/ml of analyte in spiked urine), and the recoveries were 78.9–100.8% for 1 μg/ml and 84.1–100.3% for 5 μg/ml. The application of this method to forensic or clinical samples is demonstrated. 相似文献