235 research outputs found

    X-Ray Study on Mg-Sm Alloy Produced by HPT

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    X-ray study on Mg-Sm alloy produced by HPT

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    金沢大学大学院自然科学研究科システム創成科学専攻The purpose of this study is to reveal the cause of hardening of magnesium base alloys by the high pressure torsion processing (HPT) using X-ray diffraction. HPT was applied to Mg base alloys of the Mg-Sm system (2.8-5.5 mass %Sm). HPT was performed under pressure 4GPa at 20°C and 200°C. HPT results in significant strengthening of the Mg-Sm alloys due to the formation of sub microcrystalline structure. The dynamic recrystallization was realized through the pole figure measurement and the photograph of X-ray back scattering. The Mg supersaturated solid solution decomposition during HPT was observed by the X-ray profile analysis and the calculation of lattice constants of the Mg phase

    A49T, V89L and TA repeat polymorphisms of steroid 5α-reductase type II and breast cancer risk in Japanese women

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    BACKGROUND: Breast cancer is hormone related, as are cancers of the endometrium, ovary, and prostate. Several studies have suggested that higher extracellular levels of androgens are associated with breast cancer risk, while biological evidence indicates that androgens are protective. The codon 49 alanine to threonine substitution (A49T), codon 89 valine to leucine substitution (V89L) and TA repeat polymorphisms of the steroid 5α-reductase type II (SRD5A2) gene are considered functional with respect to enzyme activity converting testosterone into dihydrotestosterone. To test the hypothesis that these three polymorphisms are associated with risk of breast cancer, a case–control study was conducted with patients of Aichi Cancer Center Hospital. METHODS: The cases were 237 patients histologically diagnosed with breast cancer, and the controls were 185 noncancer outpatients. DNA from peripheral blood was genotyped by PCR methods. RESULTS: The threonine allele of A49T was not found in our subjects. Compared with the V/V genotype of V89L, the L/L genotype was associated with a decreased risk (crude odds ratio [OR] = 0.61, 95% confidence interval [CI] = 0.36–1.05). This was also the case for the TA(9/9) genotype, with an OR of 0.58 (95% CI = 0.13–2.63) relative to TA(0/0). Among women with the TA(0/0) genotype, however, the OR for the L/L genotype was 0.46 (95% CI = 0.24–0.88) compared with the V/V genotype, and those with the V/V and TA(0/0) genotypes had the highest risk. The haplotype with the L and TA(9) repeat alleles was not found. CONCLUSION: This study is the first to our knowledge focusing on Japanese women, suggesting that SRD5A2 polymorphisms might have an association with breast cancer risk. Further large-sample studies will be required to confirm the association and to assess any interactions with environmental factors

    Influence of annealing on strength of ultrafine grained low carbon steels by ECAP

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    金沢大学大学院自然科学研究科In the present study, ultra fine-grained low carbon steel samples were processed by equal channel angular pressing (ECAP). Mechanical properties of the specimens annealed statically at several temperatures were evaluated by tensile and hardness test. In addition, grain sizes of the specimens were measured by SEM-electron back scattering pattern (SEM-EBSP) and X-ray diffraction analysis. Differential scanning calorimetry (DSC) measurement also evaluated thermal reactions in anneal process of the specimen. As a result, the grain size was changed at the temperature between 550°C and 600°C drastically and the tensile strength also became lower at the same temperature. The relation between yield stress and averaged grain diameter of specimens obeyed the Hall-Petch relation except the normalized specimen. Behavior of grain growth and recovery in structural observation by EBSP corresponded to reaction signal of the DSC curve. © (2010) Trans Tech Publications

    Effect of evodiamine on catecholamine secretion from bovine adrenal medulla

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    The effect of evodiamine on catecholamine secretion from bovine adrenal medulla was investigated. Evodiamine, a bioactive component isolated from dry unripened fruit of Evodia rutaecarpa Bentham, was found to stimulate the secretion of catecholamine from perfused bovine adrenal medulla at a concentration of 10 μM and its effect persisted for at least 30 min. This stimulatory effect of evodiamine was abolished by omission of Ca2+ from the perfusion fluid. Evodiamine (0.1-10 μM) markedly enhanced the secretion of catecholamine from the adrenal medulla induced by acetylcholine (100 μM) or high K+(56 mM). The secretion of catecholamine was promptly enhanced by acetylcholine or high K+, but returned to the control level on treatment for 20 min. However, when evodiamine was added to the perfusion fluid after acetylcholine or high K+ stimulation for 10 min, the secretion of catecholamine again increased greatly. These results indicate that evodiamine not only stimulated the secretion of catecholamine from bovine adrenal medulla but also reversed insensitivity of these cells to acetylcholine or high K+ stimulation

    Diagnosis of Gastric Cancer in Early Stage — The Clinical Ob­servation of Operated Cases

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    1. An attempt has been made to find the diagnostic criteria for early gastric cancer. It is most important to detect the evidences or suspected features of the malignant growth in incipient stage in order to attain the radical cure by surgical operation. 2. Twelve patients with early gastric cancer (groups A and B) were selected out of 476 patients who had undergone gastrectomy during the past three years in the Okayama Saiseikai General Hospital. The other 6 patients in the &#34;precancerous group&#34; (group C) were also studied, who had abnormal epithelial proliferation in the resected stomach membrane during the same period. 3. The processes of discovery of early cancer have been described. Fairly precise diagnosis can be made in the mucosal carcinoma, but it is not in the ulcer-carcinoma. It was generally difficult to estimate the degree of the malignancy and the extension of the growth preoperatively. 4. The details of the diagnostic aids are as follows. i. Negative occult blood of stool does not always mean the definite diagnostic aid. ii. The malignant gastric change may occur even in non-anacidity. Further investigations should be followed up on gastric ulcer patients if malignant alteration is under the consideration. iii. Minor roentgenological findings, such as the absence or irregularity of mucosal folds, rigid and/or overlapped contour, localized absence or decrease of the peristaltic waves and absence or bow-shaped deformity of the angulus, are of important significance. Such changes should be minutely sought for by X-ray film examination. iv. On gastroscopy and gastrocamera photography, such changes as erosion or irregular granular thickening of the membrane with abnormal reddening and edematous appearance, irregularity of ulcer edge, uneven swelling on ulcer margin with reddening and unsharpness of the edge of adherent coat on ulcer floor, must be noted in the early gastric cancer. v. It is not safe to leave a patient having stomach ulceration under a mere conservative management because it is often quite difficult to dissolve the question of malignancy of the lesion with all sorts of examinations. vi. So far as clinical examinations have indicated malignancy, histological examination must be carried out immediately at the time of operation, even when malignant lesion is absent in inspection and palpation on the exposure of the stomach. vii. On the gross observation of the resected stomach, a particular attention must be paid to erosion, depression or atrophy, irregular granular thickening and abnormal reddening on the restricted areas of the mucosal surface.</p
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