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61.
Our procedure of real-zero conversion uses a spectrum-reversal technique to convert the information of a bandlimited signal to real zeros. We conducted a simple reconstruction experiment and showed that our proposed method is essentially equivalent to the conventional technique of sine-wave crossings 相似文献
62.
T Yoshida 《Canadian Metallurgical Quarterly》1997,69(15):3038-3043
A new method is established for separating peptides in normal phase liquid chromatography using TSK gel Amide-80, carbamoyl groups bonded to a silica gel matrix, and an acetonitrile-water solution containing 0.1% trifluoroacetic acid. Peptide retention time increased with acetonitrile concentration in the initial eluent. Hydrophilic peptides with no retention in a reversed phase column were retained and separated in the present method. Separation selectivities in the present and reversed phase methods differed significantly. Two-dimensional separation of protein digest using reversed and normal phases was conducted, taking advantage of the differences in selectivities. All peptides obtained from the digest could be separated completely. The present method is useful for separating peptide mixtures in conjunction with reversed phase liquid chromatography. Peptide recovery from the Amide-80 column exceeded 80%, as with the reversed phase column, and repeatability and reproducibility were satisfactory. 相似文献
63.
I Murohashi K Yoshida A Handa M Murayoshi S Yoshida I Jinnai M Bessho K Hirashima 《Canadian Metallurgical Quarterly》1997,25(10):1042-1050
We evaluated the effects of various hematopoietic growth factors (HGFs) on the prevention of apoptosis in blasts from 19 patients with acute myeloblastic leukemia (AML) by assessing DNA ladder formation. After incubation without HGF, apoptosis was noted in all but two patients. HGFs prevented, did not affect, or enhanced apoptosis in 39 (60%), 14 (22%), or 12 (18%) of 65 suspension cultures, respectively. HGFs that prevented apoptosis also stimulated and/or synergized blast colony formation in 35 of 39 corresponding methylcellulose cultures. HGFs that alone stimulated colony formation also prevented apoptosis in all but two of 28 corresponding suspension cultures. In contrast, HGFs that did not prevent apoptosis also failed to stimulate growth in 17 of 26 corresponding methylcellulose cultures. HGFs that enhanced apoptosis alone never stimulated colony formation. After incubation, we noted enhanced c-fos and cjun genes as well as induction of p21 protein. An appropriate dose of HGF elevated c-fos, reduced c-jun and p21, induced G1/S transition, and inhibited apoptosis. In two patients, apoptosis was not induced after incubation. Cells not treated with HGF expressed no c-fos, c-jun, or c-myc, and remained in G0/G1. Taken together, our results support the conclusion that not only c-fos, cjun, and c-myc, but also p53 and p21 are required for blast apoptosis. HGF differentially prevents apoptosis and induces mitosis, and both events seem to be integral to the self-renewal of AML clonogenic cells. 相似文献
64.
M Shimabukuro T Shinzato H Yoshida F Nagamine N Takasu K Koja 《Canadian Metallurgical Quarterly》1996,87(1):86-89
A full-length cDNA clone for a progesterone membrane binding protein from porcine vascular smooth muscle cells was isolated and the complete nucleotide sequence determined. The cDNA encodes a protein of 194 amino acids with a transmembrane segment. This protein is likely to represent the first steroid membrane receptor or a part of it for which sequence information is available. 相似文献
65.
Keratin expression in cultured malignant melanoma cells has been studied only rarely. Moreover, no studies have reported of universality of keratin expression in human malignant melanoma cells. In this study, therefore, we analyzed keratin expression in eight cell lines. Using a low-salt aqueous solution without high salt and Triton X-100, as a washing buffer for keratin extraction, followed by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and immunological analysis, we demonstrated keratin expression in all eight human malignant melanoma cell lines. The keratin polypeptide expressions common to all melanoma cells were K1, K5, K10 and K14. In addition, K8, K13, K17 and K18, respectively, were detected in individual cells. A measure of keratin expression universality in malignant melanoma cells may have implications regarding their invasive and metastatic behaviors, co-expressed with vimentin. 相似文献
66.
Using the photonic band gap in photonic crystals, the fundamental waveguide structures for the light wavelength range have been developed. Based on the fine structure of these many functional devices have been proposed by analytical or numerical simulation methods and the experiments of trial manufacture. In this paper, the treatment of chiral dielectric in the Condensed Node Spatial Network for the vector potential is explained, and we show the polarization plane rotation property in air‐hole and pillar type photonic crystal waveguide structures with the chiral medium substrate. Then, we show the fundamental advantage of the air‐hole type photonic crystal waveguide structure in application to a mode converter. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 152(1): 7–14, 2005; Published online in Wiley InterScience ( www.interscience. wiley.com ). DOI 10.1002/eej.20098 相似文献
67.
CT Migita KM Matera M Ikeda-Saito JS Olson H Fujii T Yoshimura H Zhou T Yoshida 《Canadian Metallurgical Quarterly》1998,273(2):945-949
The O2 and CO reactions with the heme, alpha-hydroxyheme, and verdoheme complexes of heme oxygenase have been studied. The heme complexes of heme oxygenase isoforms-1 and -2 have similar O2 and CO binding properties. The O2 affinities are very high, KO2 = 30-80 microM-1, which is 30-90-fold greater than those of mammalian myoglobins. The O2 association rate constants are similar to those for myoglobins (kO2' = 7-20 microM-1 s-1), whereas the O2 dissociation rates are remarkably slow (kO2 = 0.25 s-1), implying the presence of very favorable interactions between bound O2 and protein residues in the heme pocket. The CO affinities estimated for both isoforms are only 1-6-fold higher than the corresponding O2 affinities. Thus, heme oxygenase discriminates much more strongly against CO binding than either myoglobin or hemoglobin. The CO binding reactions with the ferrous alpha-hydroxyheme complex are similar to those of the protoheme complex, and hydroxylation at the alpha-meso position does not appear to affect the reactivity of the iron atom. In contrast, the CO affinities of the verdoheme complexes are >10,000 times weaker than those of the heme complexes because of a 100-fold slower association rate constant (kCO' approximately 0. 004 microM-1 s-1) and a 300-fold greater dissociation rate constant (kCO approximately 3 s-1) compared with the corresponding rate constants of the protoheme and alpha-hydroxyheme complexes. The positive charge on the verdoporphyrin ring causes a large decrease in reactivity of the iron. 相似文献
68.
T Matsuba M Yamada H Suzuki A Kanai O Isozaki T Yoshida T Tsushima K Yasukawa 《Canadian Metallurgical Quarterly》1995,118(2):265-270
Starting with a previously isolated cDNA for human thyrotropin receptor (TSHR), we established a transformed myeloma cell line, SP56, which expresses human TSHR on its cell surface. Binding analysis showed that SP56 bears 1.1 x 10(5) TSHR per cell with a Kd of 2.2 x 10(-10) M. Using the purified cellular membrane, we established a TSH binding inhibition immunoglobulin (TBII) assay for autoantibodies against TSHR. We compared it with the TBII assay utilizing porcine thyroid membranes expressing porcine TSHR, which has been widely used for TBII assay, by using 96 serum samples from patients with autoimmune thyroid disease and normal individuals. Our TBII assay was more sensitive than the one using porcine TSHR: of 38 sera of patients which were judged negative for autoantibodies to TSHR (TBII value below 10%) by the latter assay, 28 were positive (above 20%) in our assay. By using a perfusion culture system, we obtained as many as 3 x 10(10) SP56 cells, from which 3,450 mg protein of the membrane could be purified; this is sufficient for 15,000 assays. The results indicate that the membrane of the myeloma cell line SP56 is more suitable for use in the TBII assay than the porcine thyroid membrane, in terms of sensitivity to autoantibodies against TSHR in human sera. 相似文献
69.
70.
T Maruo S Yoshida T Samoto Y Tateiwa X Peng S Takeuchi S Motoyama 《Canadian Metallurgical Quarterly》1998,19(6):494-504
Expression of squamous cell carcinoma (SCC) antigen emerged concurrently with squamous formation of the uterine cervix and increased during the neoplastic transformation of the cervical squamous epithelium. SCC antigen expression differed considerably among the histomorphologic cell types of cervical carcinoma. Large cell nonkeratinizing carcinoma contained high levels of the antigen. In contrast, no appreciable expression of SCC antigen was observed in small cell nonkeratinizing carcinoma. The pattern of SCC antigen expression closely coincided with EGF receptor (EGF-R) expression in cervical squamous neoplasia. This suggests that the expression of SCC and EGF-R in cervical carcinoma is related to the differentiation or dedifferentiation processes of the tumor cells. SCC production by CaSki cervical epidermoid carcinoma cells was stimulated by EGF. It seems likely that an autocrine system, in which EGF serves as the signal, may exist in cervical squamous carcinoma. 17beta-estradiol and L-triiodothyronine were found to upregulate EGF-R expression, proliferative potential and SCC production in the CaSki cervical carcinoma cells. 相似文献