DNA content of the cell nucleus in the macroalga <Emphasis Type="Italic">Porphyra yezoensis</Emphasis> (Rhodophyta)     

Kazuyo Matsuyama-Serisawa  Maki Yamamoto  Mariko Fujishita  Hirotoshi Endo  Yukihiko Serisawa  Satoshi Tabata  Shigeyuki Kawano  Naotsune Saga 《Fisheries Science》2007,73(3):738-740

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Reproductive biology of the cardinalfish Apogon lineatus in Tokyo Bay, Japan     

Gen Kume  Atsuko Yamaguchi  Ichiro Aoki and  Toru Taniuchi 《Fisheries Science》2000,66(5):947-954

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Interpopulation comparison of size and age at smolting of white-spotted charr, Salvelinus leucomaenis     

S. Yamamoto  K. Morita 《Ecology of Freshwater Fish》2002,11(4):281-284

Abstract – The relationships between size and age at smolting and juvenile growth rates were examined for 13 populations of white-spotted charr ( Salvelinus leucomaenis ). Mean smolt length (ranging 142–210 mm in fork length) and smolt age (2.4–3.7 years) varied significantly among populations and there was a significant negative relationship between smolt length and age. Mean smolt length was positively correlated with mean specific growth rate from age 0 to 1 year, whereas mean smolt age was negatively correlated with specific growth rate. The present study shows that the freshwater environment conditions operating on juvenile growth are important for moulding the phenotypic characteristics of size and age at smolting.  相似文献   

Dengue hemorrhagic fever with special emphasis on immunopathogenesis   总被引：3，自引：0，他引：3  

Kurane I 《Comparative immunology, microbiology and infectious diseases》2007,30(5-6):329-340

Dengue virus infections are a serious cause of morbidity and mortality in most tropical and subtropical areas of the world; Southeast and South Asia, Central and South America, and the Caribbean. Dengue virus infection can be asymptomatic or causes two forms of illness, dengue fever (DF) and dengue hemorrhagic fever (DHF), which is the severe form of dengue illness and often fatal. Pathogenesis of DHF has been analyzed, and two mechanisms are considered to be responsible. These include dengue serotype cross-reactive immune responses and virulence of the virus. The immunopathological mechanisms include a complex series of immune responses. Rapid increase in the levels of cytokines, especially TNF-, and chemical mediators play a key role in inducing unique clinical manifestations of DHF such as plasma leakage, shock, and hemorrhagic manifestations. It is understood that the process is initiated by infection with a virulent dengue virus, often in the presence of antibodies that enhance dengue virus infection in secondary infection, and then triggered by rapidly elevated cytokines and chemical mediators that were produced by intense immune activation. However, complete understanding of the entire pathological mechanism is far from complete, and further studies are still needed.  相似文献   

Two male sterility-inducing cytoplasms of beet (Beta vulgaris) are genetically distinct but have closely related mitochondrial genomes: implication of a substoichiometric mitochondrial DNA molecule in their evolution     

Yasuyuki Onodera  Takumi Arakawa  Rika Yui-Kurino  Masayuki P. Yamamoto  Kazuyoshi Kitazaki  Shigehiko Ebe  Muneyuki Matsunaga  Kazunori Taguchi  Yosuke Kuroda  Shiko Yamashita  Tomoyuki Sakai  Toshiro Kinoshita  Tetsuo Mikami  Tomohiko Kubo 《Euphytica》2015,206(2):365-379

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Very low vitamin C activity of orally administered L-dehydroascorbic acid.     

Yukako Ogiri  Fang Sun  Shoko Hayami  Aki Fujimura  Kinue Yamamoto  Maki Yaita  Shosuke Kojo 《Journal of agricultural and food chemistry》2002,50(1):227-229

The biological activity of L-dehydroascorbic acid (DHA), which is easily formed from L-ascorbic acid (ASC) during storage and cooking processes, has been considered to be equivalent to that of ASC on the basis of studies made several decades ago, when a specific method to determine ASC was not available. The nutritional activity of orally ingested DHA has now been evaluated by comparing ASC concentrations in 12 tissues of rats administered four different doses of ASC. Determinations were made by using the specific and sensitive method, which had been developed by us. Here it is shown that the efficiency of DHA was almost 10% of that of ASC on a molar basis, based on animal experiments using the inherently scorbutic ODS rat, which is a convenient human model animal to investigate the metabolism of vitamin C. On the basis of these findings, it is proposed that it is necessary to reevaluate the nutritional requirement of vitamin C based on both ASC and DHA contents of foods.  相似文献   

Validation of a food-frequency questionnaire for cohort studies in rural Japan     

Ogawa K  Tsubono Y  Nishino Y  Watanabe Y  Ohkubo T  Watanabe T  Nakatsuka H  Takahashi N  Kawamura M  Tsuji I  Hisamichi S 《Public health nutrition》2003,6(2):147-157

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Evaluation of biological activities of extracts from the fruiting body of <Emphasis Type="Italic">Pleurotus citrinopileatus</Emphasis> for skin cosmetics     

Tian-Xiao Meng  Shoko Furuta  Sayaka Fukamizu  Ryoko Yamamoto  Hiroya Ishikawa  Enos Tangke Arung  Kuniyoshi Shimizu  Shoji Ohga  Ryuichiro Kondo 《Journal of Wood Science》2011,57(5):452-458

Pleurotus citrinopileatus Singer has recently become a popular delicacy in East Asian countries. We prepared a methanol extract, soluble fractions from the methanol extract, and a hot water extract of the fruiting bodies of P. citrinopileatus. The biological activities such as melanin biosynthesis inhibition, tyrosinase inhibition, antioxidant activities [1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, oxygen radical absorbance capacity (ORAC), and superoxide dismutase (SOD)-like activity], antibacterial activities, and antihyaluronidase activities of these extracts were evaluated. We found that the n-hexanesoluble, diethyl ether-soluble, and ethyl acetate-soluble fractions exhibited melanin biosynthesis inhibition in B16 melanoma cells, as well as antioxidant (ORAC) and antibacterial activities. However, the n-butanol-soluble and water-soluble fractions and the methanol and hot water extracts exhibited antioxidant (DPPH radical scavenging, SOD-like activity) and antihyaluronidase activities. These results indicate that the fruiting bodies of P. citrinopileatus have the potential to be used as an ingredient in skin cosmetics.  相似文献   

Rapid, Micro-Methods to Estimate Plant Silicon Content by Dilute Hydrofluoric Acid Extraction and Spectrometric Molybdenum Method     

Kimio Saito  Akiko Yamamoto  Tongmin Sa  Masahiko Saigusa 《Soil Science and Plant Nutrition》2005,51(1):29-36

By treating 0.5 g DW of a plant sample directly with 10 ml of a dilute hydrofluoric acid solution (HF solution, 1.5 M HF—0.6 M HCl), all the silica in plant (as much as 150 mg SiO₂) was dissolved within 1 h. After dilution of the extract with 40 mL of distilled water, the silica in the extract was measured by the spectrometric molybdenum yellow method. The molybdenum yellow method, in which silica in 0.1 mL of the diluted extract can be determined in 8 min, is well suited to rapid, micro-estimations of the silica content in plants. In the micro-modification, the size of the plant sample was reduced to 100 mg DW. The analytical procedure was simple, and the analytical time was less than 2 h. The method can save much labor and time, compared with the gravimetric analysis. The dissolution with HF solution and the molybdenum yellow method were also applied to the measurement of the content of silica separated by acid digestion of rice plants. Excellent agreement in the silica measurement of rice plants was confirmed among the direct extraction method, the gravimetric method and the digestion-separation-dissolution method. In the molybdenum yellow method, the addition of boric acid enabled to mask the interference of hydrofluoric acid, and the least amount of citric acid required for the elimination of phosphorus interference was proposed. In conclusion in this report, recommended methods for the rapid estimation of the silica content in rice plants were presented.  相似文献   

暴雨径流期间前次洪水对悬移质传输影响的研究     

OkazawaHiromu  NagasawaTetuaki 《中国水土保持》2002,(7):17-17

对日本北海道西南部的两个不同土地利用方式流域的几场降雨中的悬移质输沙量进行了观测。一个流域完全被森林所覆盖 ,另一个流域农业用地占 35%。这个地区主要种植日耕型的高原作物 ,该作物系喂养菜牛的饲料。从 1 997年 5月到 1 998年 1 0月 (不包括 1 997年 1 1月至1 998年 4  相似文献