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41.
All forms of baking and processing cause a loss of nutrients, including vitamin E, but little is known about these occurrences or if they could be avoided. The objective of this research was to study the incorporation of palm oil and the stability of vitamin E in palm oil during breadmaking. Wheat meal and rye breads were baked with and without the addition of 0, 2, 5, or 8% palm oil. The eight E group vitamers (tocopherols and tocotrienols) were extracted by using accelerated solvent extraction, freeze dried, and then analyzed with normal‐phase HPLC. Compared with the controls, the inclusion of palm oil was found to increase the quantity of all forms of vitamin E in the final baked products. It is concluded that palm oil is effective in increasing the vitamin E content of whole grain bread.  相似文献   
42.
43.
Cyclooxygenase (COX) inhibitors and the intestine   总被引:1,自引:0,他引:1  
Nonsteroidal anti-inflammatory drugs (NSAIDs) have long been used for the treatment of pain and inflammation because of their inhibitory effects on cyclooxygenase (COX). For almost as long as NSAIDs have been in use, multiple adverse effects have been noted. Assessment of many of these adverse effects have been complicated because of the discovery of multiple splice variants of the cox gene, and a greater array of COX inhibitors, especially the COX-2 selective inhibitors have become available. Some of these adverse effects cannot be readily explained by the effect of these drugs on COX. This has sparked a new field of investigation into the COX-independent effects of the COX inhibitors. The major noncyclooxygenase targets of the COX inhibitors of particular relevance to inflammation and the gastrointestinal tract are phosphatidylinositol 3'-kinase Akt signaling, uncoupling of oxidative phosphorylation, PPARgamma, nuclear factor KB, mitogen activated protein kinases, and heat shock proteins.  相似文献   
44.
The purpose of this study was to determine the efficacy and cost-effectiveness of tulathromycin (DRAX) versus tilmicosin (MIC) or oxytetracycline (TET) as a metaphylactic antimicrobial in feedlot calves. Calves that received DRAX had significantly (P<.05) lower initial undifferentiated fever (UF) treatment and relapse rates; lower overall chronicity, overall mortality, and cause-specific mortality rates; higher average daily gains; and improved quality grades. However, calves that received DRAX also had poorer (P<.05) yield grades compared with calves that received MIC or TET and worse feed conversion compared with calves that received MIC. Net advantages in the DRAX group were 3.79CanDollars/animal and 16.96CanDollars/animal compared with the MIC and TET groups, respectively. Based on these results, DRAX is a more efficacious and cost-effective metaphylactic antimicrobial than MIC or TET in feedlot calves at ultra-high risk of developing UF. In addition, this study presents a comparison between two methods ("deads out" and "deads in") of calculating feedlot performance variables.  相似文献   
45.
We investigated the interacting effects of inorganic nitrogen and the main inorganic phosphorus form in dairy manure (dicalcium phosphate, CaHPO4) on growth, nutrient uptake, and rhizosphere pH of young maize plants. In a pot experiment, three levels of CaHPO4 (0, 167, and 500 mg P pot?1) were combined with nitrogen (637 mg N pot?1) applied at five NH4‐N : NO3‐N ratios (0 : 100, 25 : 75, 50 : 50, 75 : 25, and 100 : 0) and a nitrification inhibitor in a concentrated layer of a typical acid sandy soil from Denmark. 15N‐labeled NH4‐N was applied to differentiate the role of nitrification and to partition nitrogen uptake derived from NH4‐N. Among treatments including nitrogen, shoot biomass, rooting and phosphorus uptake were significantly higher at the five‐leaf stage when CaHPO4 was applied with NH4‐N : NO3‐N ratios of 50 : 50 and 75 : 25. In these treatments, rhizosphere pH dropped significantly in direct proportion with NH4‐N uptake. The fertilizers in the concentrated layer had a root‐inhibiting effect in treatments without phosphorus supply and in treatments with pure NO3‐N or NH4‐N supply. Increased nitrogen uptake as NH4‐N instead of NO3‐N reduced rhizosphere pH and enhanced acquisition of applied CaHPO4 by young maize plants, which may have positive implications for the enhanced utilization of manure phosphorus.  相似文献   
46.
A single‐factor experiment was conducted to investigate the effects of dietary astaxanthin concentration on the skin colour of snapper. Snapper (mean weight=129 g) were held in white cages and fed one of seven dietary levels of unesterified astaxanthin (0, 13, 26, 39, 52, 65 or 78 mg astaxanthin kg?1) for 63 days. Treatments comprised four replicate cages, each containing five fish. The skin colour of all fish was quantified using the CIE L*, a*, b* colour scale after 21, 42 and 63 days. In addition, total carotenoid concentrations of the skin of two fish cage?1 were determined after 63 days. Supplementing diets with astaxanthin strongly affected redness (a*) and yellowness (b*) values of the skin at all sampling times. After 21 days, the a* values increased linearly as the dietary astaxanthin concentration was increased before a plateau was attained between 39 and 78 mg kg?1. The b* values similarly increased above basal levels in all astaxanthin diets. By 42 days, a* and b* values increased in magnitude while a plateau remained between 39 and 78 mg kg?1. After 63 days, there were no further increases in measured colour values, suggesting that maximum pigmentation was imparted in the skin of snapper fed diets >39 mg kg?1 after 42 days. Similarly, there were no differences in total carotenoid concentrations of the skin of snapper fed diets >39 mg kg?1 after 63 days. The plateaus that occurred in a* and b* values, while still increasing in magnitude between 21 and 42 days, indicate that the rate of astaxanthin deposition in snapper is limited and astaxanthin in diets containing >39 mg astaxanthin kg?1 is not efficiently utilized. Astaxanthin retention after 63 days was greatest from the 13 mg kg?1 diet; however, skin pigmentation was not adequate. An astaxanthin concentration of 39 mg kg?1 provided the second greatest retention in the skin while obtaining maximum pigmentation. To efficiently maximize skin pigmentation, snapper growers should commence feeding diets containing a minimum of 39 mg unesterified astaxanthin kg?1 at least 42 days before sale.  相似文献   
47.
利用ECMWF再分析数据验证PRECIS对中国区域气候的模拟能力   总被引:52,自引:8,他引:52  
本文利用1979~1983年的ECMWF再分析数据作为准观测侧边界条件驱动Hadley气候预测和研究中心的区域气候模式系统PRECIS,验证PRECIS对中国区域的气候模拟能力。选择典型的观测站点北京模拟的日最高,最低气温、太阳短波总辐射和月均降水量与观测结果进行直接比较,显示:PRECIS具有很强的模拟地面气候季节变化的能力。全国740个台站的观测与模拟值的统计分析表明:尽管模拟的最高,最低气温在0℃附近有一‘锯齿’状的偏差,PRECIS能够很好地模拟全国范围最高,最低气温的型态分布特征;从全国范围看,模拟的降水值偏高,但显示出很强的模拟极端降水事件的能力;模拟的地面太阳短波总辐射与全国122个台站的观测结果的比较显示:PRECIS模拟的辐射值偏高,全国范围内约高22%。因此,当应用PRECIS输出结果进行气候变化的影响评价时,需要对模式的输出结果进行订正。  相似文献   
48.
Plant Foods for Human Nutrition - Chickpea is one of the most consumed legumes worldwide. Among their benefits are the high protein concentration that reflects not only at the nutritional level but...  相似文献   
49.
Myrtle rust (caused by Austropuccinia psidii) affects more than 500 known host species in the Myrtaceae family. Three different modelling approaches (CLIMEX, MaxEnt and Multi-Model Framework) were used to project the habitat suitability for myrtle rust at both global and local scales. Current data on the global occurrence of myrtle rust were collected from online literature and expert solicitation. Long-term averages of climate data (1960–1990) were sourced from WorldClim and CliMond websites. Recent reports of myrtle rust in New Zealand were used for validation of model outputs but not in model training and testing. The model outputs were combined into a consensus model to identify localities projected to be suitable for myrtle rust according to two or three models (hotspots). In addition to the locations where the pathogen is currently present, all models successfully projected independent occurrence data in New Zealand suitable for establishment of the pathogen. Climate suitability for the pathogen was primarily related to temperature followed by rainfall in MaxEnt and the CLIMEX model. The results confirmed the optimum temperature range of this pathogen in the literature (15–25 °C). Additional analysis of the precipitation variables indicated that excessive rain (more than 2000 mm in warmest quarter of the year) combined with high temperatures (>30 °C) constrain pathogen establishment. The results of the current study can be useful for countries such as New Zealand, China, South Africa and Singapore where the pathogen has not fully spread or established.  相似文献   
50.
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