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11.
Summary The usefulness of LMS in postoperative immunochemotherapy of gastric cancer was investigated. In compliance with the protocol, MMC was given at a dose of 20 mg on the day of gastrectomy, and an additional 10 mg on the next day IV. The patients receiving 600 mg Tegafur daily were then divided into two groups according to whether LMS was also given or not. LMS was administered for 3 days before the operation in a daily dose of 150 mg and for 1 year or more after operation according to a schedule of 3 days' administration followed by an 11-day interval. The 2-year follow-up demonstrated that in stage III patients, the LMS (+) regimen was superior to the LMS (–) regimen, since the former prolonged the relapse-free interval significantly. The survival rate for stage III disease was also significantly higher in the LMS (+) than in the LMS (–) group. There was no significant difference in the incidence of subjective or objective side-effects between two groups. The incidence of agranulocytosis was comparable in the two groups.Gastrointestinal Cancer Research Group, Japan Levamisole Research AssociationChairmen of the Gastrointestinal Cancer Research Group, Japan LMS Research AssociationController of the Gastrointestinal Cancer Research Group, Japan LMS Research AssociationMembers of the Data Collection and Analysis SubcommitteeThis study was carried out by the Gastrointestinal Cancer Research Group, Japan LMS Research Association (directed by Prof. Kiyoshi Inokuchi, Dept. of Surgery, Kyushu University and Prof. Eiro Tsubura, Dept. of Internal Medicine, Tokushima University). The results were presented in part at the 19th General Meeting of the Japanese Society for Gastroenterological Surgery in February, 1982  相似文献   
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ECP31, an embryogenic-cell protein from carrot (Daucus carota L.), was purified by sequential column-chromatographic steps and digested by V8 protease on a nitrocellulose membrane. The resultant peptides were separated by reverse-phased column chromatography and sequenced. The sequences obtained were 70–80% homologous to those of a late-embryogenesis-abundant protein (D34) from cotton (Baker et al, 1988, Plant Mol. Biol. 11, 227–291). The level of ECP31 in somatic embryos of carrot was increased by treatment of the embryos with 3.7 · 10–6 M abscisic acid (ABA) for 48 h, and there was no change in this enhanced level for up to 192 h in the presence of ABA. No similar enhancing effect of ABA was observed on the level of ECP31 in embryogenic callus or segments of carrot hypocotyls. In an immunohistochemical analysis, ECP31 was found in epidermal tissue and in the vascular system of ABA-treated somatic embryos.Abbreviations ABA abscisic acid - 2,4-D 2,4-dichlorophenoxyacetic acid - LEA protein late-embryogenesis-abundant protein To whom correspondence should be addressedThis work was supported in part by a grant-in-aid for Special Research in Priority Areas (Project No. 02242102) from the Ministry of Education, Science and Culture, Japan, and by Special Coordination Funds of the Science and Technology Agency of the Japanese Government.  相似文献   
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Controlling the energetics and backbone order of semiconducting polymers is essential for the performance improvement of polymer‐based solar cells. The use of fluorine as the substituent for the backbone is known to effectively deepen the molecular orbital energy levels and coplanarize the backbone by noncovalent interactions with sulfur of the thiophene ring. In this work, novel semiconducting polymers are designed and synthesized based on difluoronaphthobisthiadiazole (FNTz) as a new family of naphthobisthiadiazole (NTz)–quaterthiophene copolymer systems, which are one of the highest performing polymers in solar cells. The effect of the fluorination position on the energetics and backbone order is systematically studied. It is found that the dependence of the solar cell fill factor on the active layer thickness is very sensitive to the fluorination position. It is thus further investigated and discussed how the structural features of the polymers influence the photovoltaic parameters as well as the diode characteristics and bimolecular recombination. Further, the polymer with fluorine on both the naphthobisthiadiazole and quaterthiophene moieties exhibits a quite high power conversion efficiency of 10.8% in solar cells in combination with a fullerene. It is believed that the results would offer new insights into the development of semiconducting polymers.  相似文献   
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Abstract

In this study, four major egg white proteins were purified by two step ion exchange chromatography followed by precipitation. Lysozyme and ovalbumin were separated with Q Sepharose Fast Flow anion exchange chromatography in the first step, resulting in two peaks of lysozyme and three peaks of ovalbumin with 87% and 70% purity by HPLC, respectively. Ovotransferrin was separated with CM-Toyopearl 650 M cation exchange chromatography in the second step, giving 80% purity. Ovomucoid was precipitated from the partial purified protein fraction from the first two steps, and concentrated in the final step to yield 90% purity. Protein recoveries were estimated to be 55, 21, 54, and 21% for lysozyme, ovotransferrin, ovalbumin, and ovomuciod, respectively. Lysozyme was identified from the purified peaks using zymogram refolding gel, whereas ovalbumin was identified by western blotting. Purified ovotransferrin and ovomucoid was identified by mass spectrometry. The results indicate that this purification process is adequate for preparation of lysozyme, ovalbumin, ovotransferrin, and ovomucoid, at least on a laboratory scale.  相似文献   
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External electron radiotherapy is performed using a cone or applicator to collimate the beam. However, because of a trade-off between collimation and scattering/bremsstrahlung X-ray production, applicators generate a small amount of secondary radiation (leakage). We investigate the peripheral dose outside the radiation field of a Varian-type applicator. The dose and fluence outside the radiation field were analyzed in a detailed Monte Carlo simulation. The differences between the calculation results and data measured in a water phantom in an ionization chamber were less than ±1% in regions more than 3 mm below the surface of the phantom and at the depth of dose maximum. The calculated fluence was analyzed inside and outside the radiation field on a plane just above the water phantom surface. Changing the electron energy affected the off-axis fluence distribution outside the radiation field; however, the size of the applicator had little effect on this distribution. For each energy, the distributions outside the radiation field were similar to the dose distribution at shallow depths in the water phantom. The effect of secondary electrons generation by photon transmission through the alloy making up the lowest scraper was largest in the region from the field edge to directly below the cutout and at higher beam energies. The results of the Monte Carlo simulation confirm that the peripheral dose outside the field is significantly affected by radiation scattered or transmitted from the applicator, and the effect increases with the electron energy.  相似文献   
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Abstract

Synthesis of the title oligonucleotide bearing a phosphate function at the 5′-terminus, i.e., pCpUpCpGpUpCpCpApCpCpA, by the use of the terminal cytidylic acid unit involving a novel protecting group of 2-[2-(monomethoxytrityloxy)ethylthio]ethyl group on its 5′-phosphoryl function in terms of a cellulose acetate polymer-support is described.  相似文献   
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Abstract

Synthesis of 5-carbon-substituted 1-β-d-ribofuranosylimidazole-4-carboxamides are described. Treatment of 5-iodo derivative 8 with methyl acrylate in the presence of palladium catalyst gave (E)-5-(2-carbomethoxyvinyl)-1-(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)imidazole-4-carboxamide (9), followed by appropriate manipulations to afford various 5-carbon-substituted imidazole derivatives 1–7. The antileukemic activities of these imidazole nucleosides are also described.

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