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81.
Peanut allergy is a major cause of food‐induced severe anaphylactic reactions. To date, no medical care is available to prevent and treat peanut allergy and therefore hypoallergenic peanut varieties are of considerable health political and economic interest. Major allergens that induce IgE‐responses in peanut‐sensitive patients are Ara h 1, Ara h 2 and Ara h 3/4. In order to identify hypoallergenic peanuts, commercially locally available peanut varieties were screened for their allergen content. Ara h 1‐deficient peanuts from Southeast Asia were identified by SDS‐PAGE, immunoblotting, inhibition assays and ELISA. 2‐D PAGE analyses demonstrated the different compositions of the tested extracts and revealed a number of variations of the allergen patterns of peanuts from different varieties. Mediator release experiments of these peanut extracts demonstrated similar allergenicities as compared with standard peanut extract. These results indicate that the allergenicity of peanuts with reduced Ara h 1 content might be compensated by the other allergens, and thus do not necessarily cause a reduction of allergenicity.  相似文献   
82.
Combinatorial biosynthesis meets combinatorial pharmacology, cyanobacterial style : A new antimitotic natural product with features of both dolastatins 10 and 15 was isolated from the same Floridian Symploca sp. sample that produced the histone deacetylase inhibitor largazole. Both agents in combination are more effective in inhibiting cancer cell proliferation than either agent alone.

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83.
通过有限元模型升级,将有限元分析与现场测量相结合,其潜力毋庸置疑。然而,简单化的初始模型和缺少测量可能导致升级的模型参数隐藏了不准确的模型假设,而不是提高实际结构参数的评估。因此,所提出方法的目标主要是在采用非线性优化对参数进行评估之前,借助手工模型的精度消除不精确的模型简化。此外,引进多级响应目标函数,结合不同类型的测量获得参数评估的坚实基础。所提方法被用于世界上最大的Svinesund单孔桥,研究表明采用非线性模型可对模型参数进行精确评估。  相似文献   
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85.
We are aiming for a blue print for synthesizing (moderately complex) subcellular systems from molecular components and ultimately for constructing life. However, without comprehensive instructions and design principles, we rely on simple reaction routes to operate the essential functions of life. The first forms of synthetic life will not make every building block for polymers de novo according to complex pathways, rather they will be fed with amino acids, fatty acids and nucleotides. Controlled energy supply is crucial for any synthetic cell, no matter how complex. Herein, we describe the simplest pathways for the efficient generation of ATP and electrochemical ion gradients. We have estimated the demand for ATP by polymer synthesis and maintenance processes in small cell-like systems, and we describe circuits to control the need for ATP. We also present fluorescence-based sensors for pH, ionic strength, excluded volume, ATP/ADP, and viscosity, which allow the major physicochemical conditions inside cells to be monitored and tuned.  相似文献   
86.
Mushroom β-glucans are known for their activity as biological response modifiers and anticarcinogenic agents. β-1,3-1,6 Branched glucans with a triple helix tertiary structure are recognised as the most potent ones. In the present work, a colorimetric method for β-1,3-1,6-glucan quantification based on the dye Congo red is introduced. This method is specific for β-glucans with a triple helix. The β-1,3-1,6-glucan content of mycelia and fruiting bodies from various mushrooms was determined and compared with the total β-1,3-glucan content, measured by a fluorimetric method. The results show equal amounts of β-1,3-1,6- and total β-1,3-glucans in the analysed species but obvious differences between mycelia and fruiting bodies. On the average, 3% of mycelia and 8% of fruiting body dry mass consist of β-1,3-1,6-glucans. The average percentage of β-1,3-1,6-glucans in the total β-1,3-glucan content differs between mycelia (46%) and fruiting bodies (87%).  相似文献   
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88.
Food and nutrition security can be supported by an urban garden. The present study comprises a critical reflection on the difficulty of producing food in urban gardens in Brazil and shows the potential of food production and the obstacles to its expansion. In addition, issues related to the agroecological management of gardens are addressed and suggestions are made to improve the proposed public policies. Urban gardens are multifunctional and have social, economic and environmental impacts. They are strategically important for supporting low-income families and urban development. Through urban gardens, diverse foods and quality foods can be produced for self-consumption. This review highlights the importance of generating detailed information on urban gardens in Brazil to support policies aimed at this sector. Long-term and multidisciplinary studies are needed to evaluate the relationship between food production in urban gardens and household food and nutrition security. This approach revealed a lack of information on the amount of food produced by Brazilians in their gardens and consumed by the household. In addition, there is little information on the management of production. There is a gap relating to the impact of food produced in urban gardens and the prevalence of food and nutrition security. © 2019 Society of Chemical Industry  相似文献   
89.
Herein, nanocrystals of Er3+ and Er3+, Yb3+ co-doped NaYF4 upconversion (UC) phosphor were prepared via the reverse-microemulsion method. The impact of different concentrations of Er3+ ions on the UC emission intensity after 980?nm diode laser excitation is discussed. The structure, morphology and composition of the nanophosphors were confirmed by X-ray diffraction, transmission electron microscopy, scanning electron microscopy and the results showed the presence of NaYF4 nanocrystals with hexagonal phases of NaYF4. The UC spectra revealed two emission bands including a green and a red emission band and the CIE coordinate for the samples were estimated. The present research revealed that the reverse-microemulsion approach will be suitable for the synthesis of efficient upconversion nanophosphors.  相似文献   
90.
Magnetic Resonance Materials in Physics, Biology and Medicine - Innovative physiologic MRI development focuses on depiction of heterogenous vascular and metabolic features in glioblastoma. For this...  相似文献   
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