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101.
Radishes (Raphanus sativus L.) are members of the cruciferous vegetable family that contain many classes of biologically active phytochemicals. This study determined the phytochemical composition of the sprouts and mature taproots of 8 radish varieties. Radish sprouts contained significantly greater concentrations of glucosinolates (3.8-fold) and isothiocyanates (8.2-fold) than the mature radish taproot and also contained significantly greater concentrations of phenolics (on average 6.9-fold). The anthocyanin concentrations of the mature radish taproot were significantly greater than in the sprouts of red, pink, and purple varieties. The primary anthocyanidins present in the red and pink radish varieties were pelargonidin and delphinidin, while the primary anthocyanidin in the purple radish variety was cyanidin. Radish sprouts were between 9- and 59-fold more potent than the corresponding mature taproot at activating the antioxidant response element (ARE) in a stably transfected hepatoma cell line. The ARE activity of the radish sprouts and mature taproots was significantly correlated with the total isothiocyanate concentration of the radishes. Practical Application: Understanding the influence variety and developmental stage has on the biological activity of cruciferous vegetables provides important information for further studies examining the in vivo effects of radish treatment and foundation for providing recommendations to reduce the risk of chronic disease through dietary intervention.  相似文献   
102.
大青叶抗菌物质提取及抗菌效果研究   总被引:10,自引:3,他引:10  
赵良忠  王放银  段林东 《食品科学》2004,25(11):138-140
研究了用水浸提法抽提大青叶中抗菌物质的方法,并通过抑菌实验检验了对细菌和霉菌的抑菌能力。正交实验结果表明最佳抽提工艺为:料水比1:20,加热时间40min,回流温度100℃:滤纸片法抑菌实验发现:大青叶提抽浓缩液(浓缩比为5:1)对大肠杆菌及枯草杆菌的最低抑菌浓度为2.77%(ml,100ml)左右,青霉,黄曲霉为0.55%(ml/100ml)左右,金黄色葡萄球为0.055%(ml/100ml)左右。  相似文献   
103.
The solubility of TiO2 in tetragonal ZrO2 is 13.8±0.3 mol% ui 1300°C, 14.9±0.2 mol% at 1400°C, and 16.1±0.2 mol% at 1500°C. These solid solutions transform to metastable monoclinic solid solutions without compositional change on cooling to room temperature.  相似文献   
104.
A starch damage analytical method for use on wheat flours has been developed which is rapid, simple in operation, analytically precise, and is independent of any α-amylase present in flour, as when milled from rain damaged wheat. The new method is based on the use of an analytical grade fungal α-amylase enzyme, which is shown to be free of contaminating amyloglucosidases, and α-glucosidases which produce glucose rather than maltose. The level of analytical α-amylase per starch damage determination was obtained by reference to thin layer chromatography of the hydrolysates so as to obtain maltose as the principal reducing sugar. This ensured that adequate but not excess analytical α-amylase was present, as the undamaged starch granules are some what susceptible to α-amylase.  相似文献   
105.
运用模糊聚类分析方法整编翰林桥站流量资料初探   总被引:1,自引:0,他引:1  
主要对水文资料整编采用模糊聚类分析的方法进行尝试,利用计算机定线,使得水文资料整编全面计算机化作了初步的探索,取得一定的效果。  相似文献   
106.
Energy poverty in rural Bangladesh   总被引:2,自引:0,他引:2  
Energy poverty is a well-established concept among energy and development specialists. International development organizations frequently cite energy-poverty alleviation as a necessary condition to reduce income poverty. Several approaches used to measure energy poverty over the past 20 years have defined the energy poverty line as the minimum quantity of physical energy needed to perform such basic tasks as cooking and lighting. This paper uses a demand-based approach to define the energy poverty line as the threshold point at which energy consumption begins to rise with increases in household income. At or below this threshold point, households consume a bare minimum level of energy and should be considered energy poor. This approach was applied using cross-sectional data from a comprehensive 2004 household survey representative of rural Bangladesh. The findings suggest that some 58 percent of rural households in Bangladesh are energy poor, versus 45 percent that are income poor. The findings also suggest that policies to support rural electrification and greater use of improved biomass stoves might play a significant role in reducing energy poverty.  相似文献   
107.
A multivariate skimmilk extrusion process, designed to produce an acid coprecipitate was studied in terms of minimizing residual lactose, ash and fines. an experimental model system was utilized to simulate the extrusion process and evaluated using response surface methodology to assess the relationship between the responses (fines, residual lactose and minerals) and the process variables (concentration, pH, temperature, agitation, washing time and wash water ratio). Compromise optimum conditions were derived using the Generalized Distance Approach (GDA) and an Extended Response Surface Procedure (ERSP) which made use of the SAS RSREG procedure with and without constraints. the GDA procedure produced good results in terms of providing an optimum for a general acid casein process, while the ERSP allowed more extensive analysis of the data in terms of assessing specific processing conditions. Although more computing intensive, the ERSP conferred additional flexibility in determining optimal conditions for special situations such as extrusion processing. Both approaches are useful for process engineering, with the GDA being a more general tool while the ERSP is advantageous when the GDA procedure becomes limiting.  相似文献   
108.
CONTEXT: Many groups have developed guidelines to shorten hospital length of stay in pneumonia in order to decrease costs, but the length of time until a patient hospitalized with pneumonia becomes clinically stable has not been established. OBJECTIVE: To describe the time to resolution of abnormalities in vital signs, ability to eat, and mental status in patients with community-acquired pneumonia and assess clinical outcomes after achieving stability. DESIGN: Prospective, multicenter, observational cohort study. SETTING: Three university and 1 community teaching hospital in Boston, Mass, Pittsburgh, Pa, and Halifax, Nova Scotia. PATIENTS: Six hundred eighty-six adults hospitalized with community-acquired pneumonia. MAIN OUTCOME MEASURES: Time to resolution of vital signs, ability to eat, mental status, hospital length of stay, and admission to an intensive care, coronary care, or telemetry unit. RESULTS: The median time to stability was 2 days for heart rate (< or =100 beats/min) and systolic blood pressure (> or =90 mm Hg), and 3 days for respiratory rate (< or =24 breaths/min), oxygen saturation (> or =90%), and temperature (< or =37.2 degrees C [99 degrees F]). The median time to overall clinical stability was 3 days for the most lenient definition of stability and 7 days for the most conservative definition. Patients with more severe cases of pneumonia at presentation took longer to reach stability. Once stability was achieved, clinical deterioration requiring intensive care, coronary care, or telemetry monitoring occurred in 1% of cases or fewer. Between 65% to 86% of patients stayed in the hospital more than 1 day after reaching stability, and fewer than 29% to 46% were converted to oral antibiotics within 1 day of stability, depending on the definition of stability. CONCLUSIONS: Our estimates of time to stability in pneumonia and explicit criteria for defining stability can provide an evidence-based estimate of optimal length of stay, and outline a clinically sensible approach to improving the efficiency of inpatient management.  相似文献   
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