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The in vitro clonogenic assay has been used to assess the biological effects of estradiol-17 beta (E 2) and an antiestrogen, tamoxifen (TAM) on human breast cancer, and the results were compared with the estrogen receptor status (ER). The sera used were treated with dextran-coated charcoal to avoid the modification effects of the endogenous hormones. There was a significant difference between ER (+) and ER (-) breast cancers in the incidence of cases in which the plating efficiency of cancers increased more than 50% over those of untreated control by adding 10(-8) M of E 2 (40.2% vs. 21.3%). TAM, 10(-6) M revealed a less than 50% colony formation of the control in 30.5% of ER (+) cancers, whereas only 13.0% of ER (-) cancers showed a response to TAM. 相似文献
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Hisamatsu K Kusano KF Morita H Takenaka S Nagase S Nakamura K Emori T Matsubara H Ohe T 《Acta medica Okayama》2004,58(1):29-35
We attempted to determine the usefulness of body surface mapping (BSM) for differentiating patients with Brugada syndrome (BS) from patients with asymptomatic Brugada syndrome (ABS). Electrocardiograms (ECG) and BSM were recorded in 7 patients with BS and 35 patients with ABS. Following the administration of Ic antiarrhythmic drugs, BSM was recorded in 5 patients with BS and 16 patients with ABS. The maximum amplitudes at J0, J20, J40 and J60 were compared between the 2 groups, as were 3-dimensional maps. The maximum amplitudes at J0, J20 and J60 under control conditions were larger in patients with BS than in patients with ABS (P < 0.05). A three-dimensional map of the ST segments under control conditions in patients with BS showed a higher peak of ST elevation in the median precordium compared to that for patients with ABS. Increases in ST elevation at J20, J40 and J60 following drug administration were greater in patients with BS than in patients with ABS (P < 0.05). Evaluation of the change in amplitude of the ST segment at E5 caused by Ic drug administration was also useful for differentiating between the 2 groups. In conclusion, BSM was useful for differentiating patients with BS from those with ABS. 相似文献
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Hisako Tanaka Tadakazu Shimoda Ken Uchida Teruo Suzuki Eisei Ishikawa 《Pathology international》1986,36(10):1455-1468
Lymphocyte subsets in the tumor nests of breast carcinoma were immunohistochemically investigated and a quantitative analysis was added. The majority of cases showed predominance of T cell and suppressor T cell (T8). A decrease in number of lymphocyte subsets and the helper T (T4)/T8 ratio in the stroma of tumor nests correlated well with the progression of clinical stage and the presence of metastasis. This correlation could not be found in the peripheral region of the tumor nests. Macrophages and NK cells were infrequently observed only in the peripheral region of ductal carcinoma. T cell infiltration was prominent in medullary carcinoma with lymphocyte infiltration (MC), and macrophages, NK cells, and T zone histiocytes were frequently encountered. For the purpose of knowing the activity of T cells, IL-2 receptor (Tac) and transferrin receptor were examined irnmunohistochemically. The fact that a few activated T cells were found only in the peripheral region of tumor nest suggested the local immune response in ductal carcinoma not to be so active as to reject the tumor cells. Since numerous activated T cells were recognized in the tumor nests of MC, this type of breast carcinoma was thought to have a higher immune reactivity. There was little evidence indicating NK cells to play a role for natural cytotoxicity in breast carcinoma. ACTA PATHOL. JPN. 36 1455-1468, 1968 相似文献
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Shigeki Sekine Tadakazu Shimoda Satoshi Nimura Yukihiro Nakanishi Takayuki Akasu Hitoshi Katai Takuji Gotoda Tatsuhiro Shibata Michiie Sakamoto Setsuo Hirohashi 《Modern pathology》2004,17(11):1421-1426
We report a patient with familial adenomatous polyposis who developed high-grade dysplasia against a background of fundic gland polyposis. Two large high-grade dysplasia lesions were found in the gastric body, where numerous fundic gland polyps were present. In both lesions, the dysplastic epithelium covered non-neoplastic oxyntic glands that occasionally exhibit cystic changes. A genetic analysis for APC (adenomatous polyposis coli) revealed a somatic 50-bp deletion involving codons 1502-1517 and 2-bp deletion at codon 1465 in each lesion of high-grade dysplasia. In contrast, six of the 18 fundic gland polyps were found to harbor an identical mutation: 1-bp insertion at codon 1556. Both lesions of high-grade dysplasia and the fundic gland polyps were similarly located in the fundic gland area and were caused by the inactivation of APC; however, their mutation profiles of APC were different. These results imply that fundic gland polyps and high-grade dysplasia of the stomach have distinct preferences for APC genotypes in their development. 相似文献
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Tadakazu Shimoda Shokan Tanoue Masahiro Ikegami Yasuhiro Fujii Tetsuya Muroya Eisei Ishikawa 《Pathology international》1983,33(6):1259-1267
The present study includes a histopathological and immunohistochemical study of 4 cases of diffuse hyperplasia of gastric argyrophil cells. The mode of proliferation of these cells and the production of hormone by these cells have been documented. The distribution of microacinar nests composed of argyrophil cells was thought to be related to chronic gastritis in which there are atrophy of mucosa and intestinal metaplasia. In the case in which these nests were found only in the corpus ventriculi, there was intestinal metaplasia throughout the stomach. On the other hand, in the case in which these nests appeared only in the pyloric area, atrophy of the mucosa with mild intestinal metaplasia was observed only in the pyloric area. The microacinar nests composed of argyrophil cells were distributed in the deep mucosa at the basal portion of the glands in the area with intestinal metaplasia. Serial sections revealed a sprout composed of argyrophil cells budding from the gland with intestinal metaplastic changes. The sprout buds out from the growth zone of glands with Intestinal metaplasia and then becomes isolated and gives rise to reactive hyperplasia. The peptide hormone contained in these cells differs according to the mucosal environments. Cells containing gastrin were observed in the pyloric area, but not in the corpus ventriculi where there was marked intestinal metaplasia. The cells in this area were assumed to contain other hormones. 相似文献
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Mitsuru Itoh Toshiyuki Kitano Mitsumasa Watanabe Tadakazu Kondo Takeshi Yabu Yoshimitu Taguchi Kazuya Iwai Masaro Tashima Takashi Uchiyama Toshiro Okazaki 《Clinical cancer research》2003,9(1):415-423
We investigated the possibility of the proapoptotic lipid ceramide as an indicator of chemoresistance in leukemia. Doxorubicin (DOX) increased the ceramide level and apoptosis in drug-sensitive HL-60 cells but not in drug-resistant HL-60/ADR cells, under the condition that the uptake of DOX was not different between the two cell lines. In addition, exogenous N-acetylsphingosine (C2-ceramide) enhanced DOX-induced apoptosis in HL-60/ADR cells without affecting the expression of multidrug resistant-1 protein (MDR 1) and the uptake of DOX. A lower level of ceramide with higher activities of glucosylceramide synthase (GCS) and sphingomyelin synthase (SMS) was detected in HL-60/ADR cells than in HL-60 cells. In contrast, HL-60/GCS cells, overexpressing GCS, significantly inhibited DOX-induced ceramide increase and apoptosis. These observations suggest the involvement of ceramide regulation in drug resistance of leukemia cells. In vivo, the level of ceramide was lower in chemoresistant leukemia patients (6.4 +/- 1.8 pmol/nmol phosphate; n = 14) than in chemosensitive patients (9.5 +/- 2.7 pmol/nmol phosphate; n = 9), and the activities of GCS and SMS were more than 2-fold higher in chemoresistant leukemia cells than in chemosensitive cells. MDR-1 protein was faintly expressed in one of four chemoresistant patients, but Bcl-2 were clearly detected in four patients. Therefore, it is suggested that a decrease of the ceramide level via activation of GCS and SMS is associated with the chemoresistant condition in leukemia, probably in relation to Bcl-2 but not to MDR-1 expression. 相似文献
10.
Fallout 3H concentrations in diet samples collected from 1969 to 1988 in Akita Prefecture are reported. Since the data for samples from the 1960's and 1970's are important to understand the long-term movement of 3H in the environment, we searched for old diet samples. Recently, diet samples collected in Akita Prefecture during 1969-1982 were found and subjected to 3H analysis. The samples were originally gathered for nutrition survey programs and had been stored in a refrigerated warehouse at -20 degrees C until we located them. The free water 3H concentrations in the samples were measured and are reported here. The present results are combined with already published data; together they show 3H concentrations exponentially decrease from 1969 to 1988 with an apparent half time of 5.9 y. Levels of diet free water 3H concentrations are also similar to measured and estimated precipitation 3H concentrations in Akita City. 相似文献