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31.
BACKGROUND: The association of alcohol and fibre intake with breast cancer may be mediated by circulating sex hormone levels, which are predictors of breast cancer risk. OBJECTIVE: To evaluate the relationship of alcohol and dietary fibre intake with circulating sex hormone levels among premenopausal women. METHODS: A total of 205 premenopausal women completed a validated food-frequency questionnaire at baseline and after 2 years; blood samples taken at the same time were analysed for circulating sex hormone concentrations, including oestrone (E1), oestradiol (E2), free E2, progesterone, androstenedione and sex hormone-binding globulin, by radioimmunoassay. We used mixed models to estimate least-square means of sex hormone concentrations for alcohol intake categories and quartiles of dietary intake. RESULTS: After adjustment for covariates, alcohol consumption was moderately associated with higher circulating oestrogen levels; those who consumed more than one drink per day had 20% higher E2 (Ptrend=0.07) levels than non-drinkers. In contrast, higher dietary fibre intake was associated with lower serum levels of androstenedione (-8% between the lowest and highest quartiles of intake, Ptrend=0.06), but not oestrogens. Similarly, consumption of fruits (-12%, Ptrend=0.03), vegetables (-9%, Ptrend=0.15) and whole grains (-7%, Ptrend=0.07) showed inverse associations with androstenedione levels. CONCLUSIONS: The consistency of the observed differences in sex hormone levels associated with alcohol and fibre-rich foods indicates that these nutritional factors may affect sex hormone concentrations and play a role in breast cancer aetiology and prevention.  相似文献   
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33.
Nitrogenous Fertilizer

The production of nitrogenous fertilizer in 1953 Fertilizer Year (August 1953–July 1954) showed an increase of 293.000 metric tons or 11.4% over the preceding year through furtherance of rationalization of the industry as well as better conditions of electricity. This increase was attributable to that of ammonia form fertilizer, which was 331,000 tons over preceding year, while calcium cyanamide showed a slight decrease as per Table 1.  相似文献   
34.
Following the accident at the Tokyo Electric Power Company, Fukushima Daiichi Nuclear Power Plant (FDNPP), radiocesium (134Cs + 137Cs) concentrations in deciduous mature fruits were determined in orchards in the northern area of Fukushima Prefecture. At the time of the nuclear accident, most deciduous fruit trees were in the dormant stage prior to bud burst. To evaluate the relationship between radiocesium deposition in the soil and fruit contamination, radiocesium concentrations were measured from the 5-cm topsoil and from six fruit species across 17 orchards in 2011. The vertical distribution of radiocesium in the topsoil (0–30 cm in depth) and its spatial distribution in the 5-cm topsoil underlying the tree canopy of a peach, Prunus persica (L.) Batsh, orchard (“Akatsuki” cultivar) were also investigated. Significant correlations between the radiocesium concentration in the mature fruit and that in the 5-cm topsoil layer were observed for the 17 orchards as well as for the trees of the peach orchard. However, 93% of the 137Cs found in the 30-cm soil core was retained within the top 3 cm of the soil in the peach orchard. Considering the profile of the root of this deciduous fruit tree, we assumed a negligible level of radiocesium uptake via the roots. However, the possibility of inward migration via the bark was undeniable, because some radiocesium adhered to the tree canopy before bud burst while depositing on the soil surface. Additionally, transfer factors for peach and grape, hybrid of Vitis labrusca L. and Vitis vinifera L., from young, uncontaminated trees cultivated with contaminated soil were lower than those previously reported.  相似文献   
35.
Rational molecular design and processing, enabling large-area molecular ordering, are important for creating high-performance organic materials and devices. We show that, upon one-step hot-pressing with uniaxially stretched Teflon sheets, a polymer brush carrying azobenzene-containing mesogenic side chains self-assembles into a freestanding film, where the polymer backbone aligns homeotropically to the film plane and the side chains align horizontally. Such an ordered structure forms through translation of a one-dimensional molecular order of the Teflon sheet and propagates from the interface macroscopically on both sides of the film. The resultant wide-area bimorph configuration allows the polymer film to bend rapidly and reversibly when the azobenzene units are photoisomerized. The combination of polymer brushes with hot-pressing and Teflon sheets provides many possibilities in designing functional soft materials.  相似文献   
36.
本文论述了计算机在林业中的应用方法、范围和前景。着重介绍了计算机在林业信息分析处理上的作用、信息自动收集及计算机自动控制,以及目前发展中的3个主要方面:森林资源信息管理系统;森林经营决策系统及林业专家系统。  相似文献   
37.
Stable carbon (δ13C) and nitrogen (δ15N) isotope ratios were measured to investigate the migration of John’s snapper Lutjanus johnii and its dependence on the food resources provided within the large Matang Mangrove Forest Reserve (40,151 ha), Malaysia. John’s snapper, and its main prey food such as penaeids, Acetes shrimps and mysids, showed generally depleted δ13C values in the inner mangrove area but more enriched values in the river mouth and coastal area. Some juveniles migrated into the inner mangrove areas, although they were also distributed near the river mouth areas. Isotopic signatures of snapper fish and prey reveal the ontogenetic migration of the youngest juvenile fish (<5 cm in total length) from the coastal area into the mangrove area, shifting their dependence from the coastal food web to the inner mangrove food web with their growth. The study shows the importance of the complex interconnected mangrove waterways and associated prey animals present in the large mangrove system to juvenile John’s snapper.  相似文献   
38.
Domoic acid was found in bivalves belonging to the genus Spondylus collected randomly from the Philippines, Vietnam, Thailand and Ishigaki Island, Japan. This is the first report of domoic acid accumulating in bivalves from tropical waters. Large differences in domoic acid levels were observed among the Spondylus specimens collected from different areas. The Spondylus specimens from the Philippines and Vietnam showed higher levels of domoic acid whereas the level in Spondylus spp. from Thailand and Japan was low. The highest level of domoic acid—more than four times the safe consumption level of 20 μg/g whole tissue—was found in a specimen from the Philippines. On the other hand, bivalves other than Spondylus collected from the same area at the same time in the Philippines showed very low levels of domoic acid, showing that bivalves belonging to the genus Spondylus accumulate specifically high levels of domoic acid. These results suggest the wide distribution of causative phytoplankton in tropical waters.  相似文献   
39.
Tetrodotoxin (TTX) was detected by HPLC and LC-MS/MS in specimens of the horseshoe crab Carcinoscorpius rotundicauda collected from Tan Hai village, Vung Tau province, Vietnam, where cases of poisoning due to the consumption of horseshoe crab have frequently been reported. The soft tissue from 10 out of the 12 specimens analyzed showed considerable levels of TTX, making them unsafe for human consumption (81.2 ± 50.3 MU/g). Paralytic shellfish poisoning (PSP) toxins were also detected in all of the specimens, but the levels were low. These findings show that the frequency of occurrence of C. rotundicauda specimens with a high level of TTX is significantly high, and that the TTX is responsible for the food poisonings caused by the consumption of C. rotundicauda in this area.  相似文献   
40.
Pseudo-nitzschia multiseries loses most of its ability to produce domoic acid when it is cultured axenically. However, domoic acid production recovers when bacteria from the original culture are reintroduced to axenic cultures, indicating a bacterial association with domoic acid production in this species. In order to determine the role of bacteria in domoic acid production, an axenic strain prepared from a nonaxenic strain of P. multiseries was inoculated into media in cellophane tubes, which were then placed in a bottle containing the original nonaxenic culture. Both strains showed characteristic domoic acid production similar to that previously observed. Domoic acid level in the cells of the axenic strain in the tubes was much smaller than that of the cells outside the tubes. These results show that direct contact between living bacteria and P. multiseries is necessary for producing high levels of domoic acid in P. multiseries.  相似文献   
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