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排序方式: 共有3132条查询结果,搜索用时 19 毫秒
61.
Y Lee SA Lee JY Choi M Song H Sung S Joen SK Park KY Yoo DY Noh SH Ahn D Kang 《Nutrition journal》2012,11(1):59
ABSTRACT: BACKGROUND: The 5-year survival rate for breast cancer among Korean women has increased steadily; however, breast cancer remains the leading cause of cancer mortality among women. One-carbon metabolism, which requires an adequate supply of methyl group donors and B vitamins, may affect the prognosis of breast cancer. This aim of this study was to investigate the associations of dietary intake of vitamin B2, vitamin B6 and folate before diagnosis on the prognosis of breast cancer. METHODS: We assessed the dietary intake using a food frequency questionnaire with 980 women who were newly diagnosed and histopathologically confirmed to have primary breast cancer from hospitals in Korea, and 141 disease progression events occurred. Cox's proportional hazard regression models were used to estimate the hazard ratio (HR) and 95% confidence interval (95% CI) adjusting for age, education, recruitment sites, TNM stage, hormone status, nuclear grade and total calorie. RESULTS: There was no significant association between any one-carbon metabolism related nutrients (vitamin B2, B6 and folate) and the progression of breast cancer overall. However, one-carbon metabolism related nutrients were associated with disease progression in breast cancer patients stratified by subtypes. In ER + and/or PR + breast cancers, no association was observed; however, in ER--/PR-- breast cancers, a high intake of vitamin B2 and folate statistically elevated the HR of breast cancer progression (HR = 2.28; 95% CI, 1.20-4.35, HR = 1.84; 95% CI, 1.02-3.32, respectively) compared to a low intake. This positive association between the ER/PR status and progression of the disease was profound when the nutrient intakes were categorized in a combined score (Pinteraction = 0.018). In ER--/PR-- breast cancers, high combined scores were associated with a significantly poor DFS compared to those belonging to the low score group (HR = 3.84; 95% CI, 1.70-8.71). CONCLUSIONS: In conclusion, our results suggest that one-carbon related nutrients have a role in the prognosis of breast cancer depending on the ER/PR status. 相似文献
62.
Four % (wt/wt) aqueous solutions were prepared at corn starch:methylcellulose:whey protein isolate (CS:MC:WPI) ratios of 2:2:2, 1:2:3, 2:1:3, 2:2:0, 1:2:0 and 2:1:0. Glycerol (gly) was used as a plasticiser at CS–MC–WPI:gly ratios of 2:1, 2.5:1 and 3:1. CS–MC–WPI blend films were stronger than CS–WPI films and had lower oxygen permeability (OP) than MC–WPI films. The highest tensile strength (TS) of blend films was 8.01 ± 3.41 MPa, at CS:MC:WPI ratio of 2:2:0 and CS–MC–WPI:gly ratio of 3:1. Lowest OP value was 45.05 ± 7.24 cm3 μm m?2 per day kPa?1, at CS:MC:WPI ratio of 2:2:2 and CS–MC–WPI:gly ratio of 3:1. OP values were predictable based on relative amounts of components. However, TS and elastic modulus properties of the CS–MC–WPI blend films did not reflect the relative amounts of the components. All of CS–MC–WPI films were translucent indicating some degree of immiscibility among the CS, MC and WPI. These results indicate the influence of complex molecular interactions among the components. 相似文献
63.
Low molecular weight β-glucan stimulates doxorubicin-induced suppression of immune functions in mice
Nak-Yun Sung Eui-Baek Byun Du-Sup Song Young-Choon Yoo Jae-Kyung Kim Jong-Heum Park Beom-Seok Song Sang-Hyun Park Ju-Woon Lee Young-Beob Yu Jae-Hun Kim 《Food science and biotechnology》2012,21(3):645-651
The aim of this study was to evaluate the protective effect of low molecular weight β-glucan (LMG) against doxorubicin (DOX)-induced immune suppression of tumor-bearing mice. The tumor size and spleen cell functions such as spleen cell proliferation, cytokine production (interferon-γ and interleukin-2), and the population of CD4+ and CD8+ T cells were estimated. In the tumorbearing mice, the tumor size was significantly (p<0.05) decreased by DOX treatment. However, there was no significant difference between mice treated with high molecular weight β-glucan (HMG) and mice treated with LMG. Spleen cell proliferation and cytokine production were significantly (p<0.05) decreased in only DOX treated group, but increased in all β-glucan treated groups with DOX. Moreover, the populations of CD4+ and CD8+ T cells were also increased in the LMG-treated group. It appears that LMG effectively reduces the DOX-induced immune toxicity through activation of immune cells such as splenocytes. 相似文献
64.
Kil Sun Yoo Eun Jin Lee Daniel Leskovar Bhimanagouda S. Patil 《Journal of food science》2012,77(12):C1279-C1284
Abstract: We developed a system to run the Folin‐Ciocalteu (F‐C) total phenolic assay, in artichoke extract samples, which is fully automatic, consistent, and fast. The system uses 2 high performance liquid chromatography (HPLC) pumps, an autosampler, a column heater, a UV/Vis detector, and a data collection system. To test the system, a pump delivered 10‐fold diluted F‐C reagent solution at a rate of 0.7 mL/min, and 0.4 g/mL sodium carbonate at a rate of 2.1 mL/min. The autosampler injected 10 μL per 1.2 min, which was mixed with the F‐C reagent and heated to 65 °C while it passed through the column heater. The heated reactant was mixed with sodium carbonate and color intensity was measured by the detector at 600 nm. The data collection system recorded the color intensity, and peak area of each sample was calculated as the concentration of the total phenolic content, expressed in μg/mL as either chlorogenic acid or gallic acid. This new method had superb repeatability (0.7% CV) and a high correlation with both the manual method (r2= 0.93) and the HPLC method (r2= 0.78). Ascorbic acid and quercetin showed variable antioxidant activity, but sugars did not. This method can be efficiently applied to research that needs to test many numbers of antioxidant capacity samples with speed and accuracy. 相似文献
65.
基地位于山上,南面是道路交叉口,北面是松树林。从朝南的斜坡上可以看到远处绝佳的山景。向西穿过马路是教学楼,向北穿过松树林是宿舍楼和教学楼。这一施工地的最大挑战就是如何运用这里的斜坡使图书馆拥有一个宜人的环境条件。该项目给定的综合楼主要包括两个功能,一个是普通的图 相似文献
66.
The objectives of this study were twofold. The first was to investigate the compressive and flexural behaviors of small‐sized concrete specimens strengthened with sprayed fiber reinforced polymer (SFRP), considering various fiber lengths, fiber volumes, and concrete strengths. The second was to evaluate the strengthening effects of SFRP on the flexural behaviors of large‐sized reinforced concrete beams. U‐shaped strips and shear keys were applied to the test specimens to improve the interfacial bond resistance between the concrete surface and SFRP. POLYM. COMPOS., 36:722–730, 2015. © 2014 Society of Plastics Engineers 相似文献
67.
Sung-Wook Cho Jeong-Hyun YooHan-Kwon Chang Won-Baek KimDae-Sup Kil Jong-Gwan Ahn 《Journal of Alloys and Compounds》2011,509(18):5545-5550
Changes in the microstructure and hydrogen storage properties of Ti-Cr-V alloys were investigated after a combination of ball milling and heat treatment. Two different sets of balls and vials made of tungsten carbide (WC) and stainless steel (STS) were used for milling the samples. Ball milling using WC balls and vials induced WC contamination, and it caused compositional changes in the matrix during heat treatment. When STS balls and vials were used, meanwhile, no peak of the second phase caused by contamination was found in the X-ray diffraction (XRD) data. In the case of the sample that completed only the milling process, the crystallite size calculated from the XRD data, 20-30 nm, agreed well with the grain size obtained from transmission electron microscopy (TEM). On the other hand, for the sample that was heat treated after milling, the strain decreased from 0.74% to 0.18%, the crystallite size increased to 70-80 nm, and the grain size grew up to the level of hundreds of nanometers. The changes in microstructure induced by the ball milling and heat treatment influenced the hydrogen storage properties, such as plateau pressure, hysteresis, and phase transformation with hydrogen absorption. Thus, the relationship between the microstructure and hydrogen storage properties can be explained. 相似文献
68.
Nak‐Yun Sung Eui‐Baek Byun Sun‐Kyu Kwon Young‐Choon Yoo Pil‐Mun Jung Jae‐Hun Kim Jong‐Il Choi Mee‐Ree Kim Ju‐Woon Lee 《应用聚合物科学杂志》2011,120(4):2034-2040
We conducted this study to examine the changes in the molecular structure and physiological activities of silk sericin after γ irradiation. Sericin from Bombyx mori was extracted with an Na2CO3 solution. The molecular weight distribution of sericin increased in the gel permeation chromatography and sodium dodecyl sulfate/polyacrylamide gel electrophoresis results as the irradiation dose increased. Circular dichroism data also revealed that the α‐helix contents decreased with the irradiation dose. Ultraviolet absorption was shown a different pattern between the irradiated and unirradiated sericin. However, the Fourier transform infrared spectrum was not changed in all of the groups. Furthermore, the irradiated sericin was significantly increased in 2,2‐diphenyl‐1‐picryl‐hydrazil radical scavenging, and the tyrosinase inhibitory activities increased with irradiation dose. Therefore, γ irradiation was an effective method for producing high‐molecular‐weight sericin and for developing functional foods and cosmetics. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
69.
Poly(ε‐caprolactone)/clay nanocomposites were synthesized by in situ ring‐opening polymerization of ε‐caprolactone in the presence of montmorillonite modified by hydroxyl functionalized, quaternized polyhedral oligomeric silsesquioxane (POSS) surfactants. The octa(3‐chloropropyl) polyhedral oligomeric silsesquioxane was prepared by hydrolytic condensation of 3‐chloropropyltrimethoxysilane, which was subsequently quaternized with 2‐dimethylaminoethanol. Montmorillonite was modified with the quaternized surfactants by cation exchange reaction. Bulk polymerization of ε‐caprolactone was conducted at 110°C using stannous octoate as an initiator/catalyst. Nanocomposites were analyzed by X‐ray diffraction, transmission electron microscopy, thermo gravimetric analysis, and differential scanning calorimetry. Hydroxyl functionalized POSS was employed as a surface modifier for clay which gives stable clay separation for its 3‐D structure and also facilitates the miscibility of polymer with clay in the nanocomposites due to the star architecture. An improvement in the thermal stability of PCL was observed even at 1 wt % of clay loading. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
70.
Ni-YSZ cermet anode supports solid oxide fuel cells (SOFCs) were fabricated by high-frequency induction heated sintering (HFIHS) under 60 MPa pressure with powders synthesized by the glycine nitrate process (GNP) as well as mechanically mixed commercial powders. The HFIHS method created a uniformly porous microstructure without abnormal grain growth compared to the conventional sintering method. Samples sintered by HFIHS show higher strength and electrical conductivity than conventionally sintered samples, even though they have similar porosity. 相似文献