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Dietary antioxidants may attenuate oxidative damage from strenuous exercise in various tissues. Beneficial effects of the antioxidant astaxanthin have been demonstrated in vitro, but not yet in vivo. We investigated the effect of dietary supplementation with astaxanthin on oxidative damage induced by strenuous exercise in mouse gastrocnemius and heart. C57BL/6 mice (7 weeks old) were divided into groups: rested control, intense exercise, and exercise with astaxanthin supplementation. After 3 weeks of exercise acclimation, both exercise groups ran on a treadmill at 28 m/min until exhaustion. Exercise-increased 4-hydroxy-2-nonenal-modified protein and 8-hydroxy-2'-deoxyguanosine in gastrocnemius and heart were blunted in the astaxanthin group. Increases in plasma creatine kinase activity, and in myeloperoxidase activity in gastrocnemius and heart, also were lessened by astaxanthin. Astaxanthin showed accumulation in gastrocnemius and heart from the 3 week supplementation. Astaxanthin can attenuate exercise-induced damage in mouse skeletal muscle and heart, including an associated neutrophil infiltration that induces further damage.  相似文献   
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A rare case of the simultaneous development of medullary and follicular carcinoma of the thyroid gland in a 51-year-old Japanese woman is examined. A preoperative diagnosis was made by needle aspiration cytology. Neoplastic cells of the medullary carcinoma were positive for calcitonin and carcinoembryonic antigen, whereas the tumor cells of the follicular carcinoma were negative for these substances. This case presents evidence that, in rare cases, two malignant epithelial neoplasms of different origins can occur in the same lobe of the thyroid.  相似文献   
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We evaluated the immunological potential of adenoidal lymphocytes from children with recurrent otitis media. Interleukin-4 release and CD69 expression were lower in adenoidal lymphocytes than in peripheral blood lymphocytes (PBL). Our results suggest that there may be a difference between the immunological potential of adenoidal lymphocytes and that of PBL in children with otitis.  相似文献   
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Several reports have suggested that the prevalence of asthma in adults is currently increasing. However, recent prevalence of asthma has not reported in Japan, especially in rural-mountain areas. To investigate the prevalence of asthma in adults in Japan, we conducted clinical epidemiological research on 5066 inhabitants of Menda town, in a rural-mountain area of Japan. The study population comprised 98.7% of adults in the town, including senior high school students whose age were more than 15 years old. The prevalence of asthma among adults was 3.6%. The ratio of prevalence in males to prevalence in females was 1.44. Peaks prevalences were observed in the age ranges of 15-19 and > 70 years old in males, and 15-19, 40-49 and > 70 years old in females.  相似文献   
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Unfractionated spleen cells taken from tumor-bearing mice 2weeks after tumor implantation contained tumor-primed T cellswhich produced cytokines including IL-2 and IFN- when culturedin vitro. With progressive tumor growth this initial lymphokine-producingcapacity decreased. Here, we investigated the ability of IL-12to (I) restore suppressed IFN- production, (II) cause tumorregression and (II) induce anti-tumor protective immunity. Additionof rIL-12 to spleen cell cultures from 4- to 10-week-old tumor-bearingmice resulted in a striking enhancement in the production ofIFN- compared with cultures of these cells in the absence ofrIL-12 or of normal spleen cells in the presence of rIL-12.Five I.p. injections of rIL-12 into mice bearing s.c. tumorsinduced complete tumor regression. This was found when rIL-12was given at early (1–2 weeks), intermediate (4–5weeks) or even late (7 weeks) stages of tumor growth. Furthermore,IL-12-treated mice which rejected the primary tumor exhibitedcomplete resistance to a rechallenge with the same tumor butdid not reject a second syngenetic tumor. Immunohistochemicalanalyses following IL-12 treatment revealed that CD4+ and CD8+T cells infiltrate the tumor. More importantly, IFN- mRNA expressionwas observed in fresh tumor masses from tumor-bearing mice receivingIL-12 treatment The importance of IFN- was further demonstratedby the observation that the systemic administration of anti-IFN-mAb prior to IL-12 treatment completely abrogated the anti-tumoreffect of IL-12. Thus, these results indicate that administrationof modest levels of rIL-12 to tumor-bearing mice results intumor regression through mechanisms involving reversal of suppressedIFN- production by anti-tumor T cells and the establishmentof a tumor-specific protective immune response.  相似文献   
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