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排序方式: 共有610条查询结果,搜索用时 21 毫秒
601.
Flávio T. Rodrigues Gustavo B. Fanaro Renato C. Duarte Amanda C. Koike Anna Lucia C.H. Villavicencio 《Radiation Physics and Chemistry》2012,81(8):1157-1159
The growing consumer demand for food with sensory quality and nutritional has called for research to develop new products with consumer acceptance as cookies made from flaxseed meal, that can be inserted in diet of celiacs. Celiac disease characterized by an inappropriate immune response to dietary proteins found in wheat, rye and barley (gluten and gliadin). It can affect anyone at any age and is more common in women. The celiac disease does not have cure and the only scientifically proven treatment is a gluten free diet. Irradiation as a decontamination method used for a many variety of foodstuffs, being very feasible, useful method to increase the shelf life, effective and environmental friendly without any sensory properties significant change. Sensory analyses were used to assess gluten-free bakery foods subjected to ionizing radiation sensory attributes. 相似文献
602.
A photosensitizer [Ru(bpy)(3)](2+) catalyzes oxidative coupling reaction of enamines with silyl enol ethers under visible light irradiation by a Xe lamp or sunlight to produce γ-diketones. A 2e-oxidation process involved in this reaction is achieved by a combination of the photoexcited [Ru(bpy)(3)](2+) species and duroquinone, a 2e-acceptor. 相似文献
603.
A new quassinoid, ailantinol H, was isolated from the aerial parts of Ailanthus altissima. The structure was elucidated based on spectral evidence. 相似文献
604.
Taniguchi A Sohma Y Kimura M Okada T Ikeda K Hayashi Y Kimura T Hirota S Matsuzaki K Kiso Y 《Journal of the American Chemical Society》2006,128(3):696-697
A clear understanding of the dynamic events of amyloid beta peptide (Abeta) 1-42, such as the folding, self-assembly, and aggregation processes, would be of great significance in Alzheimer's disease (AD) research. However, elucidation of these Abeta1-42 dynamic events is a difficult issue due to uncontrolled polymerization, which also poses a significant obstacle for establishing an experimental system that clarifies the pathological function of Abeta1-42. On the basis of the O-acyl isopeptide method, we herein developed a novel photo-triggered "click peptide" of Abeta1-42, for example, 26-N-Nvoc-26-AIAbeta42, in which the photocleavable 6-nitroveratryloxycarbonyl (Nvoc) group was introduced at the alpha-amino group of Ser26 in 26-O-acyl isoAbeta1-42 (26-AIAbeta42). From the results, (1) the click peptide did not exhibit the self-assembling nature under physiological conditions due to one single modified ester; (2) photoirradiation of the click peptide and subsequent O-N intramolecular acyl migration afforded the intact Abeta1-42 with a quick and one-way conversion reaction (so-called "click"), while the click peptide was stable under nonphotolytic or storage conditions. In addition, it is advantageous that no additional fibril inhibitory auxiliaries were released during conversion to Abeta1-42. This method provides a novel system useful for investigating the dynamic biological functions of Abeta1-42 in AD by inducible activation of Abeta1-42 self-assembly. 相似文献
605.
Molecular mobility of interlocked structures exploiting new functions of advanced biomaterials 总被引:1,自引:0,他引:1
Cyclic compounds can rotate and/or slide along a polymeric chain in a polyrotaxane structure, and the mobility of the ligands linked by the cyclic compounds is closely related to enhancing the multivalent interaction with binding sites on the receptor proteins. This concept is being exploited in more practical applications in the biomedical and pharmaceutical fields, such as a non-viral gene carriers. 相似文献
606.
R. Kuroda M. Yasumoto N. Sei H. Toyokawa H. Ikeura-Sekiguchi H. Ogawa M. Koike K. Yamada 《Radiation Physics and Chemistry》2009,78(12):1102-1105
A high-power terahertz (THz) source for THz time-domain spectroscopy (THz-TDS) and THz imaging has been developed based on an S-band compact electron linac at the National Institute of Advanced Industrial Science and Technology (AIST). A THz pulse was generated as coherent synchrotron radiation (CSR) from an ultra-short electron bunch and expected to have peak power of kW-order with frequency range of 0.1–2 THz. The electro-optic (EO) sampling method with a ZnTe crystal for the THz pulse measurement has been prepared for THz-TDS system. The timing measurement between the THz pulse and a probe laser was carried out. A preliminary experiment of THz transmission imaging of an integrated circuit (IC) card has been successfully demonstrated using the THz CSR pulse and a W-band rf detector. The imaging result was experimentally compared with a result of X-ray imaging. It is confirmed that its intensity and stability are enough to perform for the THz applications. 相似文献
607.
Hiroaki Fujita Tooru Ooya Motoichi Kurisawa Hideharu Mori Minoru Terano Nobuhiko Yui 《Macromolecular rapid communications》1996,17(8):509-515
A polyrotaxane consisting of many β-cyclodextrins (β-CDs) and a triblock copolymer of poly(ethylene glycol) (PEG) and poly(propylene glycol) (PPG) capped with bulky end-groups was synthesized as a model of stimuli-responsive supramolecules for nanoscale devices. The polyrotaxane was reversibly soluble-insoluble in water in response to temperature. This was achieved through the assembled and dispersed states of β-CDs along the block copolymer. It is considered that intermolecular hydrogen bondings of β-CDs, as well as the PEG segment length of the copoloymer, are predominant factors for regulating such thermally switchable behavior of the polyrotaxane. 相似文献
608.
The supramolecular network formation through inclusion complexation between α‐cyclodextrin‐based molecular tube (MT) and poly(ethylene oxide) monocetylether‐graft‐dextran (5C16PEO‐g‐Dex40) was demonstrated. From isothermal titration calorimetric (ITC) measurement, it was confirmed that MT formed an inclusion complex with two C16PEO side chains in 5C16PEO‐g‐Dex40. From viscosity measurements, the specific viscosity of the solution containing MT and 5C16PEO‐g‐Dex40 was much larger than that containing 5C16PEO‐g‐Dex40. It is considered that MT participates in the supramolecular network formation of 5C16PEO‐g‐Dex40 through inclusion complexation with two C16PEOs grafted to independent Dex40s. 相似文献
609.
610.