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1.
The present study investigated the effects of elevated carbon dioxide concentration ([CO2]) and air temperature on the germination of seed bulbils and the seedling vigour of two Chinese yam lines. Plants were grown under two [CO2] levels, ambient and elevated (ambient + 200 μmol mol?1), and two mean air temperature regimes, 22.2 °C (ambient + 1.4 °C) and 25.6 °C (ambient + 5.2 °C). Elevated [CO2] did not affect bulbil germination under both air temperature regimes. During the early growth stage, the dry weight (DW) of leaves, vines, shoots, roots, belowground parts (roots + tubers) and whole plants were higher under elevated [CO2] than ambient [CO2] for both lines under the low- and high-temperature regimes. The values of vigour indexes (index I = germination % × seedling length and index II = germination % × seedling DW) were also higher under elevated [CO2] than ambient [CO2] for both lines. These results indicated that Chinese yam seedlings respond positively to elevated [CO2] during the early growth stage. The above:belowground DW ratios were lower under elevated [CO2] than ambient [CO2] in seedlings with very small new tubers for both yam lines, indicating that elevated [CO2] strongly affected the root growth in the early growth stage. The DWs of post-treatment seed bulbils were higher in the elevated [CO2] under both air temperature regimes. The results showed that Chinese yam used a smaller amount of the reserves in seed bulbils under elevated [CO2] than under ambient [CO2].  相似文献   
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To clarify the pathogenicity of Japanese type 1 porcine reproductive and respiratory syndrome virus (PRRSV) isolate in experimentally infected pigs, we evaluated clinical signs and monitored viremia for 21 days post-inoculation (dpi). Lungs were mottled, tanned and reddish in appearance; had lesions predominantly in the cranial, middle and accessory lobes; and failed to collapse at 10 dpi. Although microscopic lesions of lungs were reproduced using the Japanese emerging type 1 PRRSV isolate under experimental conditions, no significant differences were noted between the challenge and control groups regarding mean rectal temperature and daily weight gain. These results provide useful insights into the limited pathogenicity of single infection with the Japanese type 1 PRRSV isolate in piglets, which differ from findings in reported field cases.  相似文献   
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OBJECTIVE: Little is known about the relationship of monetary diet costs to dietary intake and obesity, particularly in non-Western populations. This study examined monetary cost of dietary energy in relation to diet quality and body mass index (BMI) among young Japanese women. DESIGN: Dietary intake was assessed by a validated, self-administered, diet history questionnaire. Diet costs were estimated using retail food prices. Monetary cost of dietary energy (Japanese yen 1000 kcal-1) was then calculated. BMI was computed from self-reported body weight and height. SUBJECTS: A total of 3931 female Japanese dietetic students aged 18-20 years. RESULTS: Monetary cost of dietary energy was positively associated with intakes of fruits, vegetables, fish and shellfish, and pulses; however, higher monetary cost of dietary energy was also associated with higher consumption of fat and oil, meat and energy-containing beverages, and lower consumption of cereals (rice, bread and noodles) (all P for trend <0.01). At the nutrient level, monetary cost of dietary energy was positively associated with intakes of dietary fibre and key vitamins and minerals, but also associated positively with intakes of fat, saturated fatty acids, cholesterol and sodium, and negatively with carbohydrate intake (all P for trend <0.0001). After adjustment for possible confounders, monetary cost of dietary energy was quite weakly but significantly negatively associated with BMI (P for trend = 0.0197). CONCLUSIONS: Increasing monetary cost of dietary energy was associated with both favourable and unfavourable dietary intake patterns and a quite small decrease in BMI in young Japanese women.  相似文献   
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To utilize lupin seeds for food and pharmaceutical applications, lupin seeds were pretreated to remove oil using hexane or carbon dioxide. Two types of lupin protein isolate were prepared. Both types of protein isolate showed good foaming activity, comparable to egg white. Protein isolate extracted under acid conditions showed higher foaming activity than protein isolate extracted at neutral pH. The lipoxygenase activity was much reduced in both of the protein isolates. The protein isolate extracted at neutral pH showed a stronger angiotensin converting enzyme inhibition than the protein isolate extracted under acidic pH. In contrast, the protein isolate extracted under acid conditions had a greater sodium cholate binding capacity, comparable to that of cholestyramine. Lupin samples showed less DPPH radical scavenging activity than deoiled soybean. The deoiling method did not affect the functional properties, lipoxygenase activity, angiotensin converting enzyme inhibition, sodium cholate binding, and radical scavenging activity.  相似文献   
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Inhibitory effects of oolong tea polyphenols on pancreatic lipase in vitro   总被引:10,自引:0,他引:10  
Fifty-four polyphenols isolated from tea leaves were evaluated for their inhibitory activities against pancreatic lipase, the key enzyme of lipid absorption in the gut. (-)-Epigallocatechin 3-O-gallate (EGCG), which is one of major polyphenols in green tea, showed lipase inhibition with an IC50 of 0.349 microM. Moreover, flavan-3-ol digallate esters, such as (-)-epigallocatechin-3,5-digallate, showed higher activities of inhibition on lipase with an IC50 of 0.098 microM. On the other hand, nonesterified flavan-3-ols, such as (+)-catechin, (-)-epicatechin, (+)-gallocatechin, and (-)-epigallocatechin, showed zero and/or the lowest activities against pancreatic lipase (IC50 > 20 microM). These data suggested that the presence of galloyl moieties within the structure was required for enhancement of pancreatic lipase inhibition. It is well-known that flavan-3-ols are polymerized by polyphenol oxidase and/or heating in a manufacturing process of oolong tea. Oolonghomobisflavans A and B and oolongtheanin 3'-O-gallate, which are typical in oolong tea leaves, showed strong inhibitory activities with IC50 values of 0.048, 0.108, and 0.068 microM, respectively, even higher than that of EGCG. The oolong tea polymerized polyphenols (OTPP) were prepared for the assay from oolong tea extract, from which the preparation effectively subtracted the zero and/or less-active monomeric flavan-3-ols by preparative high-performance liquid chromatography. The weight-average molecular weight (Mw) and number-average molecular-weight (Mn) values of OTPP were 2017 and 903, respectively, by using gel permeation choromatography. OTPP showed a 5-fold stronger inhibition against pancreatic lipase (IC50 = 0.28 microg/mL) by comparison with that of the tannase-treated OTPP (IC50 = 1.38 microg/mL). These data suggested that the presence of galloyl moieties within their chemical structures and/or the polymerization of flavan-3-ols were required for enhancement of pancreatic lipase inhibition.  相似文献   
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Salivary secretory immunoglobulin A (sIgA) concentrations of prospective guide dogs for the blind were determined to clarify whether salivary sIgA is useful in evaluating the potential suitability of guide dogs for the blind. Saliva was collected from 73 prospective guide dogs in the kennel on day 1 (the day of separation from volunteer puppy-raisers), 2, 3, 7 and 14 during the estimation period (at about 1 year old). We selected particularly suitable dogs (superior dogs) and unsuitable dogs (inferior dogs) on the basis of the trainers' estimation. All dogs were divided into two groups, those were acceptable dogs would become the guide dogs and rejected dogs could not become guide dogs. The sIgA concentrations in superior dogs gradually increased from day 1 to 14 and those in inferior dogs remained at low levels. Moreover, the sIgA concentrations on day 14 in the acceptable dogs were significantly higher than those in rejected dogs. The cut-off point of sIgA concentrations on day 14 using an ROC curve was 90 EU/ml, and the specificity of the estimation at this point (70.4%) was higher than that of trainers' estimation (50%). Moreover, parallel testing using both trainers' estimation and sIgA estimation, showed that specificity was further improved (79.5%). The present study showed that sIgA concentration was extremely useful in estimating the adaptive ability for guide dogs for the blind.  相似文献   
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