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排序方式: 共有1338条查询结果,搜索用时 15 毫秒
1.
Reiko Yu-Ito Kazuko Ôba Ikuzo Uritani 《Bioscience, biotechnology, and biochemistry》2013,77(8):2087-2091
In addition to HMG-CoA reductase, another HMG-CoA utilizing enzyme is present in the Mt fraction of sweet potato root tissue and its activity interferes with the assay to HMG-CoA reductase activity. 相似文献
2.
Hidekatsu Yokoyama Shin-ichi Niwa Kenji Itoh Reiko Mazuka 《Biological cybernetics》1996,75(2):137-140
On the basis of a temporal model of animal behavior we conducted temporal analysis of eye movements in schizophrenic subjects
(n=10) and normal controls (n=10). We found a fractal property in schizophrenic subjects, the fixation time of eye movement during reading ambiguous and
difficult sentences showing a clear inverse power law distribution. An exponential distribution of a nonfractal nature was
found in normal controls.
Received: 21 July 1995/Accepted in revised form: 30 April 1996 相似文献
3.
This study examined the effects of nitrogen anaesthesia and cycloheximide injection on memory of the classically-conditioned fly, Phormia. 1 M NaCl solution was given to each fly as a conditioning stimulus and 0.5 M sucrose solution was the unconditioned stimulus that induced the proboscis extension response. The training period was as short as 2 min and testing was usually carried out 2 hr later. At varying times (0–60 min) between training and testing, flies were anaesthetized with nitrogen gas for 25 sec. When flies were anaesthetized immediately after training the effect of nitrogen gas was the greatest and few flies showed any conditioned response, but the sensitivity of memory to nitrogen gas declined as the interval between training and nitrogen treatment became longer, and such treatment had no effect on memory when the interval was longer than 30 min. The effect on memory of cycloheximide, an inhibitor of peptide bond synthesis, was also investigated. The injection of cycloheximide (0.37 μg) immediately after training diminished the memory, but when given 1 hr after training it had no effect on memory. These results show that the memory in Phormia has two phases, stable and an unstable phase, like long-term and short-term memory in vertebrates. 相似文献
4.
Mathew A. Maliakal Mepur H. Ravindranath Reiko F. Irie Donald L. Morton 《Glycoconjugate journal》1994,11(2):97-104
In the measurement of total lipid-bound sialic acids involving periodic acid oxidation, as in the periodate-resorcinol assay, the inner sialic acids of disialoglycolipids (such as GD3 and GD2) are not involved because their 2,8 ketosidic linkages are resistant to periodic acid oxidation, even after acid/enzyme hydrolysis or alkali pretreatment. However, the sialic acids from these glycolipids can be recovered completely after cleavage of 2,8 linkages byV. cholerae sialidase in the presence of cholic acid, sodium dodecyl sulphate and calcium. Interestingly, removal of calcium or detergent(s) or both significantly minimizes the sialidase action on the disialyl residues of these gangliosides. Therefore, we recommend sialidase (Vibrio cholerae) pretreatment of the glycolipids in the presence of cholic acid, SDS and Ca2+ for complete recovery of sialic acids from di- and polysialogangliosides and for accurate measurement of total lipid-bound sialic acids by periodate-resorcinol assay.Presented at the Second International Glycobiology Symposium which was held in San Francisco, CA, USA (14 February 1994). 相似文献
5.
The Expression of Two Splice Variants of Metabotropic Glutamate Receptor Subtype 5 in the Rat Brain and Neuronal Cells During Development 总被引:3,自引:0,他引:3
Reiko Minakami Ken-ichiro Iida Noriko Hirakawa Hiroyuki Sugiyama 《Journal of neurochemistry》1995,65(4):1536-1542
Abstract: We previously reported that a variant with extra amino acid residues exists in the metabotropic glutamate receptor subtype 5 (mGluR5). Either of the two isoforms, named mGluR5b and mGluR5a for the isoforms with and without the inserted sequence, respectively, generated Ca2+ -activated Cl− current when expressed in Xenopus oocytes. We herein report that these two isoforms are produced by the alternative splicing of the exon skipping type. When examined during the course of postnatal development, the major mGluR5 isotype mRNA was observed to switch from mGluR5a to mGluR5b in the rat hippocampus and the cerebral cortex. We also investigated two cell lines that could be differentiated into neuron-like cells in vitro. Whereas the mGluR5b mRNA was hardly detectable in either undifferentiated or differentiated NG108-15 cells, the relative amounts of the two variant mRNAs changed after the induction of differentiation in the P19 cells. An extracellular application of trans - d,l -1-amino-1,3-cyclopentanedicarboxylate on the neuron-like P19 cells induced intracellular Ca2+ mobilization, thus suggesting that the cells could express functional mGluR(s) coupled to phospholipase C and other components that could mediate the signal transduction pathway. This cell line may thus provide a model system for studying both mGluR5 expression and other mGluR-induced phenomena at the molecular level. 相似文献
6.
Yuichi Takeuchi Reiko Fukumoto Hirokazu Kasahara Takeshi Sakaki Mitsutoshi Kitao 《Plant cell reports》1995,14(9):566-570
Cotyledons excised from dark-grown seedlings of cucumber (Cucumis sativus L.) were cultured in vitro under UV radiation at different wavelengths, obtained by passage of light through cut-off filters with different transmittance properties. Growth and the synthesis of chlorophyll (Chl) in cotyledons were inhibited and malondialdehyde was accumulated upon irradiation at wavelengths below 320 nm. Exogenous application of scavengers of free radicals reversed the growth inhibition induced by UV-B. Measurement of the fluorescence of Chl a suggested that electron transfer in photosystems was affected by UV-B irradiation. On the basis of these results, the involvement is postulated of active species of oxygen in damages to thylakoid membranes and the growth inhibition that are induced by UV-B irradiation.Abbreviations Chl
chlorophyll
- Fm
maximal fluorescence (dark)
- Fm
maximal fluorescence (light)
- Fv
variable fluorescence (dark)
- Fv
variable fluorescence (light)
- MDA
malondialdehyde
- O2
Superoxide radical
- PS
photosystem
- qN
non-photochemical quenching of fluorescence
- qP
photochemical quenching of fluorescence
- UV-BBE
biologically effective UV-B radiation
- WL(T = 0.5)
wavelength at which 50% transmittance occurs 相似文献
7.
A new germacranolide isolated from M. sieboldii was shown to be 15-acetoxycostunolide by spectroscopic and chemical methods. 1H NMR spin decoupling and NOE experiments in the presence of a lanthanide shift reagent were used for structure elucidation. 相似文献
8.
Giuliano Armando E. Irie Reiko F. Morton Donald L. 《Cancer immunology, immunotherapy : CII》1981,10(4):243-249
Summary The oncofetal antigen-I (OFA-I) has been defined as an immunogenic antigen that is expressed on human cancer cells and is cross reactive with fetal brain tissue. Quantitative variations in the expression of OFA-I among different cultured melanoma cell lines were determined by absorption techniques based on functionally monospecific anti-OFA-I serum. Allo-antibodies were removed by absorption with lymphoblasts autologous to an OFA-I-positive target cell. Functional monospecificity toward OFA-I was confirmed by complete absorption with a specimen of fetal brain but not by liver from the same fetus.Of 14 melanoma cell lines tested, two did not express OFA-I, whereas 12 expressed the antigen to varying degrees. Five of the cell lines were highly antigenic, and serum absorbed with 5×105 of any of these cell lines could reduce the anti-OFA-I titer (1 : 96) at least four-fold. OFA-I was detected on biopsied melanomas autologous to the antigenic cultured cells. The ability to select highly antigenic cell lines could be useful in further attempts to characterize OFA-I and to monitor tumor immunity in vitro. Antigenic cell lines may improve the response of patients treated in trials of immunotherapy. 相似文献
9.
Toshihiko Ubuka Masahiro Kinuta Reiko Akagi Shozo Kiguchi Miyabi Azumi 《Analytical biochemistry》1982,126(2):273-277
A procedure for the simultaneous preparation of S-sulfo-l-cysteine and l-alanine 3-sulfinic acid is described. The method is based on the quantitative reaction between sulfite and S-(2-amino-2-carboxyethylsulfonyl)-l-cysteine. The yield was 95% for S-sulfo-l-cysteine and 91% for l-alanine 3-sulfinic acid. The reaction was also applied to the quantitative determination of sulfite in biological materials. In this procedure, sulfite reacts with S-(2-amino-2-carboxyethylsulfonyl)-l-cysteine. Separation of the reaction product, S-sulfo-l-cysteine, is done by ion-exchange fractionation, and it is determined with acid ninhydrin reagent 2 (M. K. Gaitonde, 1967, Biochem. J.104, 627–663). The recovery was 96.8 ± 0.3%. 相似文献
10.
Synthesis of two ω-aldehydoalkyl 1-thioglycosides of d-glucopyranose and of d-galactopyranose is described. 3-Oxopropyl and 2-oxoethyl 1-thioglycosides were prepared by treating a tetra-O-acetyl-1-thioaldose with either acrolein or 2-bromoacetaldehyde, followed by O-deacetylation under mild conditions. These ω-aldehydoalkyl 1-thioglycosides were successfully attached to bovine serum albumin (BSA) by reductive alkylation as described previously. With the 3-oxopropyl 1-thioglycosides, much higher levels of sugar attachment (e.g., ~80 mol of sugar per mol of BSA) were attained than hitherto possible with any sugar derivative tested. 相似文献