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251.
Zafar TA Weaver CM Jones K Moore DR Barnes S 《Journal of agricultural and food chemistry》2004,52(10):2827-2831
The effect of inulin on isoflavone absorption and the effect of isoflavones and synergy with inulin on calcium absorption in rats was investigated. Rats (n = 48) were divided into three groups and fed inulin (50 mg/g), isoflavone (8 mg/g) or inulin + isoflavone (50 mg/g + 8 mg/g) diets for 21 days. After a 2-h fast, rats were given (45)Ca orally or intraperitoneally, together with 25 mg of calcium as calcium acetate. Blood and femurs were collected 4 days later. Sera were analyzed for isoflavones using HPLC-MS, femurs for (45)Ca by beta-scintillation counting, and total femoral calcium by atomic absorption spectroscopy. Both groups fed isoflavones had similar and significantly higher weight-adjusted total femoral calcium content compared to the inulin-fed group (p < 0.0001). (45)Ca absorption was significantly higher (p < 0.01) when isoflavones were added to the diet, and serum equol was significantly lower (p < 0.01) when inulin was added to the diet containing isoflavones. We conclude that isoflavones enhance calcium absorption, without synergy from inulin, and that inulin decreases equol production. 相似文献
252.
A fully automated rain exclusion canopy system has been designed and constructed to study the impact of simulated acid rain on the growth and yield of agricultural crops. The system consists of three, mobile greenhouse shelters which exclude ambient rainfall and apply simulated acid rain (SAR) treatments to crops established in field plots. All aspects of the field system are controlled by a microcomputer and data acquisition system. In addition, elevated ambient levels of gaseous pollutants (e.g. O3, SO2, NOx) are reduced in field plots via an air exclusion system consisting of large blowers, potassium permanganate-treated alumina filters and perforated polyethylene tubes. Gaseous pollutants can be injected into the treatment plots via the blowers. 相似文献
253.
KENG‐HSIANG CHENG YU‐CHING CHIAO HSIN‐YU SHIH TAI‐YU LEE TA‐SHUN CHO 《Growth and change》2011,42(4):517-548
The purpose of this study was to investigate how Taiwanese high‐tech firms' foreign direct investment (FDI) leads to agglomeration and competition among cities in China. By using social network analysis to analyze 1,111 subsidiaries affiliated with 270 multinational corporations (MNCs) during the years between 1988 and 2006 in 30 major Chinese cities, this study finds that: 1) agglomeration in Chinese cities falls into three primary categories: the hub cluster, the communication‐extended cluster, and the computer‐extended cluster. Among the aforementioned clusters, the hub cluster is the most critical in terms of firm location, and therefore is often a high‐priority investment site for Taiwanese high‐tech firms. 2) Chinese cities fall into four primary groups, or “blocks”: the core block, the coast block, the inland block, and the periphery block; these groups were determined by applying a structural equivalence analysis of which members of each type are in competition with one another. By linking the findings of the urban network characteristics to Chinese regional economic policies, this study provides guidance to aid executives in determining the optimal location for future FDI. Implications and suggestions for host country governments in terms of firms' investment strategies are also discussed. 相似文献
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Laboratory-raised Northeirn blue jays (Cyanocitta cristata) have been observed tearing pieces from pages of newspaper and utilizing them as tools to rake in food pellets which were otherwise out of reach. The frequency of this behavior was dependenit upon the motivational state of the jay and the presence of food pellets. 相似文献
256.
Jones C 《Science (New York, N.Y.)》2007,318(5857):1715
257.
A bacterial streptomycin resistance gene (SPT) was engineered to make it possible to detect visually the transposition of the maize transposon Activator (Ac) in tobacco. In the presence of streptomycin, transgenic seedlings carrying the SPT gene appear green, whereas those carrying an SPT:: Ac construct display clones of green cells on a white background. Fully green seedlings arise in the progeny of SPT:: Ac transformants as a result of excision of Ac before fertilization. About half of these germinal revertants carry a transposed Ac element. Therefore, SPT:: Ac constitutes an efficient marker for selecting plants that have undergone transposition. In maize, there is a negative effect of increasing Ac dosage on the frequency and timing of Ac transposition. This negative effect is not observed in tobacco with the streptomycin variegation assay. 相似文献
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Paleomagnetic data and marine magnetic surveys suggest that the Bay of Biscay was created by rifting due to an anticlockwise rotation of the Iberian peninsula. The period during which movement occurred is not known precisely, but a rotation, amounting to 22 degrees, appears to have taken place in post-Eocene time. To provide independent evidence on the age of the rift, bottom samples from the Biscay abyssal plain have been related to the distribution of seismic reflectors within the sediments. The investigation shows that a large part of the Bay of Biscay was in existence in late Cretaceous times and that the data can be interpreted in terms of some early Tertiary rotation. However, the amount of possible Tertiary opening is appreciably less than the paleomagnetic results suggest. In view of the fact that reflectors of Middle-Upper Miocene age can be traced as undisturbed horizons across the bay, all tectonic movements must have ceased by the early Miocene. 相似文献