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51.
This study was designed to evaluate the effect of the oral administration of fruit extracts (lemon and Japanese apricot) combined with red-ginseng on the endurance and availability of metabolic substrates in ICR mice. Administration of the fruit extracts and red-ginseng (RG) (1:1) significantly increased swimming capacity, by 40%, with increased expenditures of non-esterified fatty acids and triglycerides in the plasma of the mice after 1 week of feeding. There was no significant increase in swimming capacity with the fruit extract alone. These results suggest that the fruit extract could synergistically elevate the effects of red-ginseng on swimming capacity in the mice by increasing fat utilization and reducing the consumption of stored glucose.  相似文献   
52.
The enzyme activities in different fractions of Dioscorea japonica Thunb. and 1,1-diphenyl-2-picryl hydrazyl radical scavenging activity in 15 natural plant pigments from black rice, purple sweet potato, yellow bitter melon, yellow paprika, red cabbage, yellow gardenia, blue gardenia, Chinese foxglove, mulberry leave, onion peel, grape peel, mulberry, red beet, gromwell, and cactus were determined. The antioxidant activity in the cosmetic composition of mulberry leaves, grape peel, mulberry, and red cabbage pigments was relatively high in comparison with all other studied plants. Enzyme activities in investigated plants were evaluated as superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX). The cosmetic composition of mulberry leaf pigment had the highest SOD enzyme activity of 67.1% while onion peel pigment showed the lowest SOD enzyme activity of 15.3%. The activity of CAT and APX from cosmetic composition of natural plant pigments has also been investigated. Both CAT and APX showed higher values in the cactus, mulberry, and red cabbage cosmetic compositions in comparison with other plant pigments. The cosmetic composition in EtOAc extract of D. japonica Thunb. had the highest SOD enzyme activity while the BuOH and EtOH extracts were comparatively low. CAT and APX activities showed significantly high values in EtOH and EtOAc extracts. The antioxidant enzyme activities of D. japonica Thunb. differ significantly in different plant pigments during their extraction. In conclusion, we showed that the plant pigments and D. japonica Thunb. had the potent biological activities. Therefore, these plant resources having anti-aging components could be good materials for development of source of natural cosmetics.  相似文献   
53.
Cyanidin, an anthocyanidin found in fruits and vegetables, has been reported to possess anti-cancer effects. However, there is no study on the chemopreventive effect of cyanidin against neoplastic cell transformation and its molecular mechanisms. In the present study, we compare the anti-carcinogenic effects of cyanidin and cyanidin-3-glucoside (C3G) and investigate their underlying mechanisms. The inhibitory effect of cyanidin on EGF-induced cell transformation was higher than those of C3G in JB6 P+ mouse epidermal (JB6 P+) cells. Both cyanidin and C3G showed dose-dependent radical scavenging activities. It is indicated that the divergent inhibitory effects of cyanidin and C3G are not due to their antioxidant activities. We found that cyanidin, but not C3G, inhibited the EGF-induced Akt/p70S6K phosphorylation. Moreover, cyanidin directly suppressed the activity of PI3K by binding to PI3K directly in an ATP-competitive manner, which indicates that PI3K is one of the molecular targets of cyanidin.  相似文献   
54.
55.
Mixed-effects linear regression models have become more widely used for analysis of repeatedly measured outcomes in clinical trials over the past decade. There are formulae and tables for estimating sample sizes required to detect the main effects of treatment and the treatment by time interactions for those models. A formula is proposed to estimate the sample size required to detect an interaction between two binary variables in a factorial design with repeated measures of a continuous outcome. The formula is based, in part, on the fact that the variance of an interaction is fourfold that of the main effect. A simulation study examines the statistical power associated with the resulting sample sizes in a mixed-effects linear regression model with a random intercept. The simulation varies the magnitude (Δ) of the standardized main effects and interactions, the intraclass correlation coefficient (ρ), and the number (k) of repeated measures within-subject. The results of the simulation study verify that the sample size required to detect a 2×2 interaction in a mixed-effects linear regression model is fourfold that to detect a main effect of the same magnitude.  相似文献   
56.
Titanium implants and BMP-7 in bone: an experimental model in the rabbit   总被引:2,自引:0,他引:2  
This study evaluates the effect of rhBMP-7/OP-1 on the osseointegration of commercially pure titanium implants in an experimental implant model in rabbits. Threaded titanium implants with two transverse parallel canals were inserted in the femur and tibia of rabbits. The canals were filled with, 10 g of BMP-7/collagen carrier, pure collagen carrier or were left empty as a control. The stiffness of the implant fixation was evaluated by Resonance Frequency Analysis (RFA) at baseline and four weeks postoperativly. Percentage of bone ingrowth in the canals was measured on microradiographs. Histomorphometry along the threaded part of the implants was performed on 15 m thin sections. The results from the RFA demonstrated a higher mean value for the BMP-7 treated implants in the tibia than the carrier treated implants but not compared to the control implants. The control implants in the tibia demonstrated more bone ingrowth in the upper canal than to the carrier or the BMP-7 treated implants. Apart from these differences there were no significant effects of BMP. In this study BMP-7 did not contribute to any substantially improved bone anchorage of titanium implants.  相似文献   
57.
Abstract

Pairs trading is an instance of statistical arbitrage that relies on heavy quantitative data analysis to profit by capitalising low-risk trading opportunities provided by anomalies of related assets. A key element in pairs trading is the rule by which open and close trading triggers are defined. This paper investigates the use of time series regression to define the rule which has previously been identified with fixed threshold-based approaches. Empirical results indicate that our approach may yield significantly increased excess returns compared to ones obtained by previous approaches on large capitalisation stocks in the Korean equities market.  相似文献   
58.
The characteristics and growth behaviors of alumina dielectric layer formed by anodic oxidation were investigated. The aluminum oxide layer anodized at 400 V was predominantly amorphous alumina, but at the applied potentials more than 500 V, amorphous and crystalline γ-alumina were existed in anodic oxide layer and the ratio of γ-alumina increased with the increasing applied potential. During the heat treatment at 600°C or higher temperature, amorphous alumina layer was transformed into the crystalline γ-alumina. The phase transition of anodic amorphous alumina into crystalline depends on anodic applied potentials and heat-treatment temperatures.  相似文献   
59.
Tumor-associated (TA) autoantibodies have been identified at the early tumor stage before developing clinical symptoms, which holds hope for early cancer diagnosis. We identified a TA autoantibody from HBx-transgenic (HBx-tg) hepatocellular carcinoma (HCC) model mouse, characterized its target antigen, and examined its relationship to human HCC. The mimotopes corresponding to the antigenic epitope of TA autoantibody were screened from a random cyclic peptide library and used for the detection of serum TA autoantibody. The target antigen of the TA autoantibody was identified as an oncogenic bi-functional purine biosynthesis protein, ATIC. It was upregulated in liver cancer tissues of HBx-tg mouse as well as human HCC tissues. Over-expressed ATIC was also secreted extracellularly via the cancer-derived exosomes, which might cause auto-immune responses. The cyclic peptide mimotope with a high affinity to anti-ATIC autoantibody, CLPSWFHRC, distinguishes between serum samples from HCC patients and healthy subjects with 70.83% sensitivity, 90.68% specificity (AUC = 0.87). However, the recombinant human ATIC protein showed a low affinity to anti-ATIC autoantibody, which may be incompatible as a capture antigen for serum TA autoantibody. This study indicates that anti-ATIC autoantibody can be a potential HCC-associated serum biomarker and suggests that autoantibody biomarker’s efficiency can be improved by using antigenic mimicry to native antigens present in vivo.  相似文献   
60.
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