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排序方式: 共有271条查询结果,搜索用时 213 毫秒
261.
Nakamura A Watanabe K Ojima T Ahn DH Saeki H 《Journal of agricultural and food chemistry》2005,53(19):7559-7564
Scallop tropomyosin (TM), the major allergen of shellfish, was prepared from adductor muscles and reacted with four reducing sugars to investigate the effect of the Maillard reaction on the allergenicity of TM. The IgE-binding ability of TM increased significantly with the progress of the reaction with glucose, ribose, and maltose, but not with maltotriose. The allergenicity was enhanced at the early stage of the Maillard reaction, and the trend of the effect depended on the type of reducing sugar used. 2,4,6-Trinitrobenzenesulfonic acid treatment of the lysine residues in TM showed that the protein surface charge resulting from the Maillard reaction had no effect on the enhancement of the allergenicity. Thus, the change in the allergenicity would be closely related to the structural change caused by the Maillard reaction. 相似文献
262.
Sheng-An Tang Qianxiang Zhou Wen-Zhi Guo Yuling Qiu Ran Wang Meihua Jin Wenjing Zhang Ke Li Takao Yamori Shingo Dan Dexin Kong 《Marine drugs》2014,12(7):4200-4213
Stellettin B was isolated from marine sponge Jaspis stellifera. In vitro antitumor activities were investigated on 39 human cancer cell lines. Stellettin B exhibited highly potent inhibition against the growth of a human glioblastoma cell line SF295, with a GI50 of 0.01 μM. In contrast, stellettin B showed very weak inhibitory activity on normal cell lines including HMEC, RPTEC, NHBE and PrEC, with GI50s higher than 10 μM, suggesting its relatively selective cytotoxicity against human cancer cells compared to normal human cell lines. We then focused on the antitumor activity of this compound on SF295 cells. Flow cytometric analysis indicated that stellettin B induced apoptosis in SF295 cells in a concentration-dependent manner. Further study indicated that stellettin B increased the production of ROS, the activity of caspase 3/7, as well as the cleavage of PARP, each of which is known to be involved in apoptosis. To investigate the molecular mechanism for cell proliferation inhibition and apoptosis induction, effect on the phosphorylation of several signal proteins of PI3K/Akt and RAS/MAPK pathways was examined. Stellettin B inhibited the phosphorylation of Akt potently, with no activity on p-ERK and p-p38, suggesting that inhibition of PI3K/Akt pathway might be involved in the antiproliferative and apoptosis-inducing effect. However, homogenous time-resolved fluorescence (HTRF) assay indicated that stellettin B did not inhibit PI3K activity, suggesting that the direct target might be signal protein upstream of Akt pathway other than PI3K. 相似文献
263.
Olov?Karlsson Tsutomu?Ikeda Takao?Kishimoto Kengo?Magara Yuji?Matsumoto Shuji?HosoyaEmail author 《Journal of Wood Science》2004,50(2):141-150
A novel method for analysis of benzylic ether type lignin–carbohydrate bonds has been developed by using model compounds. Four diastereomers of model compound 3-(4-hydroxy-3-methoxyphenyl)-2-(2-methoxyphenoxy)-3-(methyl -d-glucopyranoside-6-O-yl)-1-propanol (GGMGP), were ozonized in acetic acid/water/methanol 16:3:1 for 1h at 0°C. The product from ozonation of each diastereomer was saponified and the corresponding -etherified tetronic acid (TAMGP) was isolated using ion exchange chromatography. Minor amounts of methyl -d-glucopyranoside (MGP) and small amounts of a gluconic acid etherified with tetronic acid (TAGLCA), tetronic acid, gluconic acid, and glyceric acid were detected in the product mixture of ozonated benzylic ether type model compounds. The results suggest that a benzyl ether bond between lignin and carbohydrate is rather stable during the ozone treatment. Acid treatments with sulfuric acid or trifluoroacetic acid of the derived TAMGP led to cleavage of the glucosidic bond but only a small amount of products (tetronic acid and glucose) resulting from cleavage of the -ether bond were formed. The successful chemical treatments were used for studies of benzylic ether bonds in Japanese red pine. The results suggest the presence of benzylic ether bonds to polysaccharides in the wood.Part of this paper was presented at the 10th International Symposium of Wood and Pulping Chemistry (ISWPC), Yokohama, 1999; the 11th ISWPC, Nice, 2001; and as a rapid comunication in J Wood Sci (2000) 46:263–265 相似文献
264.
Cryopreservation is becoming a very important tool for the long-term storage of plant genetic resources and efficient cryopreservation protocols have been developed for a large number of plant species. Practical procedures, developed using in vitro tissue culture, can be a simple and reliable preservation option of potato genetic resources rather than maintaining by vegetative propagation in genebanks due their allogamous nature. Cryopreserved materials insure a long-term backup of field collections against loss of plant germplasm. Occurrence of genetic variation, in tissue culture cells during prolonged subcultures, can be avoided with suitable cryopreservation protocols that provide high regrowth, leading and facilitating a systematic and strategic cryo-banking of plant genetic resources. Cryopreservation protocols for potato reviewed here, can efficiently complement field and in vitro conservation, providing for preservation of genotypes difficult to preserve by other methods, wild types and other species decided as priority collections. 相似文献
265.
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267.
Nakagiri Takao Kato Hisaaki Maruyama Seiji Hashimoto Satoko Horino Haruhiko Sakurai Shinji 《Paddy and Water Environment》2019,17(3):463-473
Paddy and Water Environment - This study aims to investigate a possibility of quantitative assessment of the relationship between return flow from paddy fields and river regime by using hydrogen-... 相似文献
268.
Luis Galarza Yasunori Akagi Kazumi Takao Chang Sun Kim Nitaro Maekawa Akihiro Itai Esther Peralta Efrén Santos Motoichiro Kodama 《Journal of General Plant Pathology》2015,81(3):201-210
Native Trichoderma spp. were isolated from agricultural fields in several regions of Ecuador. These isolates were characterized via morphological observation as well as molecular phylogenetic analysis based on DNA sequences of the rDNA internal transcribed spacer region, elongation factor-1α gene and RNA polymerase subunit II gene. Fifteen native Trichoderma spp. were identified as T. harzianum, T. asperellum, T. virens and T. reesei. Some of these strains showed strong antagonistic activities against several important pathogens in Ecuador, such as Fusarium oxysporum f. sp. cubense (Panama disease) and Mycosphaerella fijiensis (black Sigatoka) on banana, as well as Moniliophthora roreri (frosty pod rot) and Moniliophthora perniciosa (witches’ broom disease) on cacao. The isolates also showed inhibitory effects on in vitro colony growth tests against Japanese isolates of Fusarium oxysporum f. sp. lycopersici, Alternaria alternata and Rosellinia necatrix. The native Trichoderma strains characterized here are potential biocontrol agents against important pathogens of banana and cacao in Ecuador. 相似文献
269.
Takao Masumoto Hitoshi Toritani Minoru Tada Akira Shimizu 《Paddy and Water Environment》2008,6(1):5-14
This special issue deals with water and food as it applies to water resources and rice production in the Mekong River Basin.
The range of papers reflects not only the broad interest but also the complexity of the topic. These reports are mainly based
on the research carried out by the project, “Assessment of the Impact of Global-Scale Change in Water Cycles on Food Production
and Alternative Policy Scenarios”. Hence the special issue gives a brief overview of the structure, goals, outcomes, and future
direction of the above project. What we do in this paper are: (1) giving an overview of the project’s structure and goals,
(2) stating the five common outcomes and several more specific results, and (3) looking forward to the future direction of
the project. The aim of our research is to draw up scenarios for optimum water-resource distribution and to develop social
guidelines, measures, and policies to help solving food and environmental problems by developing a world water–food model
that emphasizes rice production in Monsoon Asia. We have integrated all of the data gathered and the research results into
a food supply and demand model combined with a water-cycle analysis. We included operational factors, such as water-cycle
change, water demand, water supply, and water distribution in the model. Emphasis is placed on the use of efficient resource-management
technologies for proper use of water resources in agricultural and other sectors. The water–food model has been developed
as a tool for evaluating technical decisions derived under various policy scenarios. 相似文献
270.