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61.
The bioactive monacolin K found in red mold rice (RMR) is identical in structure to lovastatin, and has the effect of lowering the cholesterol level in human blood. Statins not only lower atherosclerosis caused by thrombus, but also reduce the death rate from coronary artery disease. This study was designed to evaluate the effects of Monascus purpureus NTU 803 fermented-RMR on blood coagulation and anticoagulation factors in hyperlipidemic rats. Rats were fed a high-lipid diet for 8 weeks to induce hyperlipidemia and fed various doses of RMR. The results showed that RMR prolonged the bleeding time of the rats, inhibited platelet coagulation, lowered the fibrinogen content in the blood, increased the antithrombin III and protein C content in the blood, and reduced lipid plaque in the aorta. RMR was effective for preventing the formation of thrombus and reducing the occurrence of atherosclerosis.  相似文献   
62.
To achieve competitiveness in the global textile and clothing (T&C) manufacturing sectors, strategic planning is required. New product development (NPD) in a revised and updated configuration of resources can have a profound leveraging effect on business competitiveness. The strategic determinants of NPD may lead to sources of competitive advantage for T&C firms. Against this background, this study constructs a research framework, in line with the resource-based view and transaction cost theory, to explore how the strategies regarding NPD can be conceived and deployed to achieve superior competitiveness. An in-depth case study of a representative Taiwanese T&C manufacturer has been employed and examined. The manufacturer has acquired resources, various (dynamic) capabilities and knowledge through its NPD process, resulting in core competences and sources for competitive advantages. The implementation of NPD has allowed the T&C manufacturer to provide an increasing variety of new products and to upgrade its services in order to serve a wider range of buyers, and as a result, continuously capturing business opportunities in today’s dynamic markets.  相似文献   
63.
Circular dichroism (CD) was used to investigate the conformations of arginine-rich histones, H3 (III or f3) and H4 (IV or f2a1), and DNA in the complexes prepared by four different methods: (A) NaCl gradient dialysis with urea; (B) NaCl gradient dialysis without urea; (C) direct mixing in 2.5 x 10(-4) M EDTA, pH 8.0; and (D) direct mixing in 0.01 M sodium phosphate, pH 7.0. Using the CD spectrum of native chromatin as a criterion to judge the closeness of a complex to its native state, it was observed that a complex made by direct mixing at low ionic strength (methods C and D) is better than the ones made by NaCl gradient dialysis with or without urea (methods A and B). It is explained as a result of lack of ordered secondary structures in histones due to the presence of urea in method A or due to nonspecific aggregation in NaCl without urea (method B). Compared with all the earlier reports in literature on the CD of histone-DNA complexes, the CD spectra of arginine-rich histone-DNA complexes prepared by methods C and D are closest to that of native chromatin both in shape and in amplitude. These results imply (a) that arginine-rich histones play an important role in maintaining the conformation of chromatin and (b) that the binding of these two histones to DNA prepared by methods C and D are close to that in native chromatin. Noticeable variation in conformation of free and bound histone and histone-bound DNA has also been observed in histone H3 with one or two cysteine residues, and in reduced or oxidized state even when the complexes were prepared and examined in the same condition. CD spectra of arginine-rich histones in 0.01 M phosphates, pH 7.0, indicate the presence of alpha-helix which could be responsible for a favorable binding of the less basic regions of these histones to DNA under this condition as demonstrated by thermal denaturation (Yu, S. .S, Li H. J., and Shih, T. Y. (1976), Bio-chemistry, the preceding paper in this issue). To preserve or generate alpha-helical structures in histones seems to be a critical step in reconstituting good histone-DNA complexes.  相似文献   
64.
Antioxidant activities of aqueous extracts of selected plants   总被引:1,自引:0,他引:1  
The antioxidant properties of 25 edible tropical plants, expressed as Trolox equivalent antioxidant capacity (TEAC), were studied using DPPH (1,1-diphenyl-2-picrylhydrazyl free radical) scavenging and reducing ferric ion antioxidant potential (FRAP) assays. Their cupric ion chelating activities (CCA) and total polyphenol contents (TPC) were also determined. A strong correlation between TEAC values obtained for the DPPH assay (TEACDPPH) and those for the FRAP assay (TEACFRAP) implied that compounds in the extracts were capable of scavenging the DPPH free radical and reducing ferric ions. A satisfactory correlation of TPC with TEACDPPH and TEACFRAP suggested that polyphenols in the extracts were partly responsible for the antioxidant activities while its correlation with CCA was poor, indicating that polyphenols might not be the main cupric ion chelators. Principal component analysis (PCA) indicated that TEACDPPH, TEACFRAP and TPC contributed to the total variation in the antioxidant activities of the plants.  相似文献   
65.
The contents of total phenolics, total anthocyanins, total proanthocyanidins and antioxidant activities were measured using 2,2-diphenyl-1-picrylhydrazyl radicals scavenging activity, ferric reducing antioxidant power, lipid peroxidation inhibition ability and ABTS radical-scavenging activity assays. These were compared in the seed coats of common bean (Phaseolus vulgaris L.) cultivar Hwachia and its eighteen NaN3-induced mutants. NaN3-induced mutants generally accumulated more total phenolics (19% more), total anthocyanins (65% more) and total proanthocyanidins (4% more) than Hwachia (containing 29.94 mg g−1 total phenolics, 0.31 mg g−1 total anthocyanins and 12.94 mg g−1 total proanthocyanidins, respectively). Anthocyanidins including delphinine, cyanidin and pelargonidin were detectable in seed coat, each with different levels depending on the tested accessions. Significant correlations (average of 0.847 across all comparisons, p < 0.01) were found between the tested antioxidant activities, total phenolics, total anthocyanins and total proanthocyanidins. Mutants SA-11-2, SA-13-2 and SA-34-2 that are enriched with antioxidants may be useful in food and other applications.  相似文献   
66.
Flavonoids contents, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activities and the ferric-reducing antioxidant power (FRAP) were compared in three black soybean varieties CRWD, Tainan 3 and Tainan 5. Varietal differences in antioxidant contents existed among the tested varieties. Variety CRWD accumulated more total phenolics (7.49 mg g−1) and isoflavones (1.77 mg g−1) than varieties Tainan 3 (7.05 mg g−1 total phenolics and 1.58 mg g−1 isoflavones) and Tainan 5 (4.38 mg g−1 total phenolics and 0.63 mg g−1 isoflavones). CRWD also accumulated more proanthocyanidins in seed coat than Tainan 3 and Tainan 5. CRWD also demonstrated greater DPPH and FRAP activities than the other two cultivars. Stepwise regressions indicated that both DPPH and FRAP activities were correlated well with the total contents of phenolics and flavonoids, with total phenolics being the most important anti-oxidative factor. The present results indicate that CRWD has greater anti-oxidative responses than Tainan 3 or Tainan 5, and is useful in functional food and other applications.  相似文献   
67.
There is a growing concern over the food safety issue related to increased incidence of cooking oil adulteration with recycled cooking oil (RCO). The objective of this study was to detect fresh palm olein (FPO) adulteration with RCO using fatty acid composition (FAC) and Fourier-transform infrared spectroscopy (FTIR) spectral analyses combined with chemometrics. RCO prepared in the laboratory was mixed with FPO in the proportion ranged from 1% to 50% (v/v) to obtain the adulterated oil samples (AO). FACs for FPO, RCO, and AO were determined using gas chromatography equipped with a flame ionization detector (GC-FID). The compositions of most fatty acids in RCO lied within the normal ranges of Codex standard, except for C8:0, C10:0, C11:0, C15:0, trans C18:1, and polyunsaturated fatty acids (PUFAs), C20:5. PUFAs showed a consistent decreasing trend with increasing magnitude of change with respect to increasing adulteration level and thus might be a good indicator for detecting FPO adulteration with RCO. The evaluation parameters (coefficient of determination, root mean standard error) of the FTIR-partial least square (PLS) model of palm oil adulteration with recycled oil are R2 = 0.995 and 3.25, respectively. For FTIR spectral analysis, the distinct variations in spectral regions and aberrations in characteristic bands between FPO and RCO were observed. The optimized PLS calibration model developed from normal spectral of the combined region at 3602–3398, 3016–2642, and 1845–650 cm?1 overpredict the adulteration level. On the other hand, the discriminant analysis classification model was able to classify the FPO and AO into two distinct groups. Improvement of the principles of combined techniques in authenticating AO from fresh oil is beneficial as a guideline to detect adulteration in cooking oil.  相似文献   
68.
改良型湿壁塔液膜传质特性与端末效应的研究   总被引:2,自引:0,他引:2       下载免费PDF全文
本文采用疋田晴夫等提出的改良型湿壁塔作为建立研究传质的基础实验装置.测定了液膜厚度沿壁的分布,实验结果表明膜厚的实验值与理论值吻合较好;又选用CO_2-H_2O系统对塔的液膜传质特性进行了研究,并提出了液膜传质系数的无因次准数关联式;实验结果与渗透理论计算值比较,获得了良好的一致性.研究还表明通过简单地操作控制即能消除由端末效应引起的偏差.因此改良型湿壁塔是进行气液传质研究的良好装置.  相似文献   
69.
运动饮料配方设计概论   总被引:7,自引:0,他引:7  
运动中,人体生理发生一系列的变化,包括水分损失、血糖/糖原消耗、电解质损失等,导致运动中/后的疲劳和运动能力下降。以运动中人体生理特点为基础,通过讨论运动前/中/后补充水、碳水化合物及电解质的问题,论证了运动饮料配方设计的原理依据。  相似文献   
70.
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