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121.
Scirrhous gastric cancer is characteristic in that cancer cells proliferate and invade with prominent fibrosis. To search for the expression of specific carbohydrate chains in scirrhous gastric cancer, we have examined the glycosphingolipid composition of scirrhous cancer tissues (n=10) in comparison with that of non-scirrhous cancer tissues (n=10) by means of two-dimensional thin layer chromatography, followed by fast atom bombardment mass spectrometry of the individual glycolipids and immunostaining analysis. The major neutral glycosphingolipids from scirrhous gastric cancer tissues were identified as ceramide monohexoside, ceramide dihexoside, globotriaosyl ceramide (Gb3) and globoside (Gb4), while the major acidic glycosphingolipids were II3 Neu-Acα-LacCer, II3 NeuAcα2-LacCer and sulfatide. Relative concentrations of Gb3 and Gb4 in scirrhous gastric cancer tissues (Gb3+ Gb4=58%) were two times higher than those in non-scirrhous gastric cancer tissues (29%). Orthotopic fibroblasts cloned from scirrhous gastric cancer tissues showed similar high concentrations of Gb3 and Gb4 to scirrhous gastric cancer tissues. Furthermore, immunohistochemical study revealed that Gb3 and Gb4 were expressed intensely on the fibroblasts. On the other hand, analysis of glycosphingolipids in four scirrhous gastric cancer cell lines yielded the following results. i) The contents of Gb3 and Gb4 were low (6%), compared with orthotopic fibroblasts (62%). ii) Significant amounts of Lea (pentaglycosylceramide) and Leb (hexa- and heptaglycosylceramides), which could not be detected in scirrhous cancer tissues, were observed. The results show that the major neutral glycosphingolipids such as Gb3 and Gb4 of scirrhous gastric cancer tissues were derived from orthotopic fibroblasts and not from the cancer cells.  相似文献   
122.
A 72-year-old Japanese woman, suffering from squamous cell lung cancer with brain metastasis, underwent 2 courses of combination chemotherapy, consisting of cisplatin and vindesine. Although both the primary tumor and the brain metastasis regressed markedly, she developed left ocular pain with blurred vision. An abnormal mass was found in the left iris, and cytologic examination of the aqueous aspirate revealed a few malignant cells, which, when examined by electron microscopy, were considered to be derived from squamous cell carcinoma of the lung.  相似文献   
123.
The purpose of this study was to apply an electronic nose system for evaluation of unpleasant odor in tablets containing L-cysteine, an unpleasant odor drug, and demonstrate the odor masking ability of thin-layer sugarless coated tablets, which we have newly developed, by both electronic nose system and sensory evaluations. We demonstrated the qualitative evaluation of the unpleasant odor using air as a reference indicator and the quantitative evaluation of the unpleasant odor using the distances between air and samples in the electronic nose system evaluation. The electronic nose system evaluation was positively and well-correlated with the sensory evaluation by volunteers. We suggest that the electronic nose system evaluation is appropriate as an alternative or a support method for sensory evaluation by volunteers. As the results of both electronic nose system and sensory evaluations, we demonstrated that the thin-layer sugarless coated tablets have excellent masking ability of the unpleasant odor, equivalent to that of sugar-coated tablets due to the dense coating layers.  相似文献   
124.
It is still in doubt whether the standard-dose growth hormone (GH) used in Japan (0.5 IU/kg/week, 0.167 mg/kg/week) for growth hormone deficiency is effective for achieving significant adult height improvement in non-growth hormone deficient (non-GHD) short children. We compared the growth of GH-treated non-GHD short children with that of untreated short children to examine the effect of standard-dose GH treatment on non-GHD short children. GH treatment with recombinant human growth hormone (rhGH) was started before the age of 11 yr in 64 boys and 76 girls with non-GHD short stature registered at the Foundation for Growth Science who have now reached their adult height. In 119 untreated boys and 127 untreated girls whose height standard deviation score (SDS) was below –2 SD at the age of 6 yr, height growth was followed until 17 yr. Height SDS was significantly lower before GH treatment in the GH-treated group than at the age of 6 yr in the untreated group, in both sexes. Adult height and adult height SDS were significantly greater in the untreated group than in the GH-treated group, in both sexes, although the change in height SDS did not differ significantly. Height SDS was significantly lower before GH treatment in the GH-treated group than at the age of 6 yr in the untreated group, so 57 boys and 57 girls whose height SDS at the age of 6 yr in the untreated group closely matched the height SDS before GH treatment in the GH-treated group were chosen for comparison. Height SDS did not differ significantly between the GH-treated group before GH treatment and the untreated group at the age of 6 yr, nor were there differences between these subgroups in adult height, adult height SDS, or height SDS change, in either sex. The effect of GH treatment is reported to be dose-dependent and doses over 0.23 mg/kg/week are reported to be necessary to improve adult height in non-GHD short children. Currently, the GH dose is fixed at 0.175 mg/kg/week in Japan, and we expected to find, and indeed concluded, that ordinary GH treatment in Japanese, non-GHD short children does not improve adult height.  相似文献   
125.
Tamoxifen (TAM) is used as the standard endocrine therapy for breast cancer patients and as a chemopreventive agent for women at high risk for this disease. Unfortunately, treatment of TAM increases the incidence of endometrial cancer; this may be due to the genotoxic damage induced by TAM metabolites. Formation of TAM-DNA adducts in rat liver correlates with the development of hepatocarcinoma. TAM-DNA adducts are proposed to be formed through O-sulfonation and/or O-acetylation of alpha-hydroxylated TAM and its metabolites. However, the role of O-sulfonation and O-acetylation in the formation of TAM-DNA adducts has not been extensively investigated. Rat or human hydroxysteroid sulfotransferases (HST), acetyltransferases, and liver cytosol were incubated with calf thymus DNA, alpha-OHTAM, and either 3'-phosphoadenosine 5'-phosphosulfate (PAPS) or acetyl coenzyme A (acetyl-CoA) as a cofactor and analyzed for TAM-DNA adduct formation, using 32P postlableling/polyacrylamide gel electrophoresis analysis. TAM-DNA adduct was formed when PAPS, not acetyl-CoA, was used. No TAM-DNA adducts were produced using human N-acetyltransferase I and II. HST antibody inhibited approximately 90% of TAM-DNA adduct formation generated by the cytosol or HST, suggesting that HST is primarily involved in the formation of TAM-DNA adducts. The formation of TAM-DNA adducts with rat liver cytosol and HST was much higher than that of human liver cytosol and HST. Our results indicate that TAM-DNA adducts are formed via O-sulfonation, not O-acetylation, of alpha-hydroxylated TAM and its metabolites.  相似文献   
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129.
The thymidylate synthase (TS) inhibition rate was measured after tegafur (FT) administration (1.5 g/day, at least 10 days) in 7 sigmoid colon cancer patients. The TS inhibition rate decreased as the interval between the time of the last administration and the time of the tumor resection increased longer. This study provides basic data for considering methods of drug administration and assessment of modification, for example, by leucovorin. © 1993 Wiley-Liss, Inc.  相似文献   
130.
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