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排序方式: 共有897条查询结果,搜索用时 15 毫秒
71.
Shinsuke Yamanaka Ikuo Nakamura Hirokazu Nakai Yo-Ichiro Sato 《Genetic Resources and Crop Evolution》2003,50(5):529-538
The direct ancestor of rice (Oryza sativa L.) is believed to be AA genome wild relatives of rice in Asia. However, the AA genome wild relatives involve both annual and perennial forms. The distribution of the retrotransposon p-SINE1-r2, a short interspersed nuclear element (SINE) at the waxy locus was analyzed in diverse accessions of the AA genome wild relatives of rice (O. rufipogon sensu lato). Most annual wild rice accessions had this retrotransposon, while most perennial types lacked this element, contradicting results to the previous studies. Results presented here suggest that O. sativa has dual origin that lead to indica-japonica differentiation. Results suggest the indica line of rice varieties evolved from the annual genepool of AA genome and the japonica varieties from the perennial genepool of AA genome wild rice. 相似文献
72.
Nakamura Y Suganuma E Matsuo T Okamoto S Sato K Ohtsuki K 《Journal of agricultural and food chemistry》1999,47(2):544-549
Fushimi sweet pepper, "Fushimi-togarashi", is one of the "Kyo-yasai", traditional vegetables, in Kyoto, Japan. The chloroform fraction of Fushimi sweet pepper showed bioantimutagenicity on UV induced mutation in Escherichia coli B/r WP2. The bioantimutagen was purified with silica gel chromatography and identified as 2, 4-nonadienal (ID(50) = 20 microg/plate) on the basis of GC retention time and EI-MS spectrum of authentic 2,4-nonadienal. The sweet pepper also contained a known bioantimutagen, benzaldehyde (ID(50) = 2 mg/plate). Additive bioantimutagenicity was also observed by 2, 4-nonadienal with benzaldehyde. 2,4-Nonadienal did not show bioantimutagenicity in an UV excision repair deficient strain, E. coli B/r WP2s uvrA(-)(). Furthermore no delay of the first cell division after UV irradiation was observed in E. coli B/r WP2. These results indicate that the bioantimutagenic activity of 2, 4-nonadienal on UV mutagenesis might depend on the excision repair system in E. coli B/r WP2. 相似文献
73.
Shoji T Mutsuga M Nakamura T Kanda T Akiyama H Goda Y 《Journal of agricultural and food chemistry》2003,51(13):3806-3813
Procyanidin fractions from apple were separated according to the degree of polymerization using normal phase chromatography. Evaluation of physiological functionalities of procyanidins requires individual structural determination. However, it is difficult to elucidate the structure of procyanidins, in particular those with (+)-epicatechin (1) or (-)-catechin (2) units, and determine whether the interflavanoid bonds are 4beta-->8 or 4beta-->6 without cleavage and acetylation. Structural determination used LC-MS and low-temperature NMR. Nine procyanidins were separated by preparative HPLC consisting of three well-known procyanidins [procyanidin B1 (3), procyanidin B2 (4), and procyanidin C1 (5)] and six new procyanidins [epicatechin-(4beta-->8)-epicatechin-(4beta-->8)-catechin (6); epicatechin-(4beta-->6)-epicatechin-(4beta-->8)-catechin (7); epicatechin-(4beta-->6)-epicatechin-(4beta-->8)-epicatechin (8); epicatechin-(4beta-->8)-epicatechin-(4beta-->6)-catechin (9); epicatechin-(4beta-->8)-epicatechin-(4beta-->6)-epicatechin (10); and epicatechin-(4beta-->8)-epicatechin-(4beta-->8)-epicatechin-(4beta-->8)-epicatechin (11)]. Compounds 6-11 were detected for the first time as apple constituents. 相似文献
74.
H Kikuchi A Nakamura K Tsuji 《Journal of the Association of Official Analytical Chemists》1988,71(5):1057-1062
A sensitive method is described to determine trace quantities of ethylene oxide (EO) in EO-sterilized intraocular lenses (IOLs). An IOL is dipped in ethanol containing 0.25 ppm propylene oxide (PO) in a 4 mL vial, 2 drops of freshly distilled hydrobromic acid is added through a septum, and the mixture is warmed at 50 degrees C for 24 h. It is then neutralized by vigorous shaking with sodium bicarbonate, dehydrated with anhydrous sodium sulfate, and filtered. The filtrate is injected into a gas chromatograph with electron-capture detection, and the peak height ratio of ethylene bromohydrin/propylene bromohydrin is measured. EO residue is calculated from the calibration curve obtained through a similar procedure with the standard EO/PO solutions. The limit of determination is 0.04 microgram/lens (ca 2.0 ppm). When EO residue levels were determined for IOLs sampled at 3 different aeration periods after sterilization, we found that 9 days of aeration was necessary to meet the U.S. Food and Drug Administration proposed limit for EO residue in IOLs. 相似文献
75.
R. Ishikawa S. Yamanaka Y. Fukuta S. Chitrakon C. Bounphanousay K. Kanyavong L.-H. Tang I. Nakamura T. Sato Y.-I. Sato 《Genetic Resources and Crop Evolution》2006,53(2):245-252
The purpose of this study was to assess the extent of genetic erosion of traditional upland germplasm in northern Thailand
as a result of gene-flow from distinct strains carrying different genotypes. Even modern variety specific markers have not
been developed, there is a comparative population in Laos. Thus, both populations were compared with various characters to
evaluate gene-flow from modern variety to landraces. Glutinous and glabrous strains are predominated in Laos. However, such
strains were drastically decreased in north–east Thailand. Gene diversity is higher in Thailand, compared to Laos at seven
isozyme loci. This was a result of the higher frequencies of Indica strains and heterozygotes in Thailand. Plastid type was
also determined by using an INDEL marker. Nearly half of Indica strains carried the Japonica plastid. Heterozygotes also tended
to carry Japonica cytoplasm. Such nuclear–cytoplasm substituted strains and heterozygotes were probably generated by natural
hybridization. Japonica strains tended to be a maternal donor rather than Indica ones. Or Indica strains would easily release
pollens, which grow outside of upland fields. 相似文献
76.
El-Abasy M Motobu M Na KJ Shimura K Nakamura K Koge K Onodera T Hirota Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(8):865-871
The effects of oral administration of sugar cane extracts (SCE) on Eimeria tenella oocysts infection in chickens were studied with 2 different experiments. In Experiment 1, 3-week-old inbred chickens (MHC; H.B15) were inoculated into the crop with SCE (500 mg/kg/day) for 1 day or 3 consecutive days, and then challenged with E. tenella sporulated oocysts (2 x 10(4) cells/chicken). In Experiment 2, 1-week-old chickens were orally administered SCE at the same dose for 3 consecutive days, and then initially infected with E. tenella sporulated oocysts (2 x 10(3) cells/chicken). At 2 and 3 weeks of age, these chickens were immunized intravenously with the mixed antigens of sheep red blood cells (SRBC) and Brucella abortus (BA). At 4 weeks of age, chickens were challenged with E. tenella sporulated oocysts (1 x 10(5)/chicken). Challenged chickens with E. tenella oocysts showed markedly decreased body weight gain/day, severe hemorrhage and great number of shedding oocysts in feces and high lesion scores. Oral administration of SCE and initial infection with oocysts (2 x 10 (3)/chicken) resulted in a remarkable improvement in body weight gain/day, hemorrhage, the number of shedding oocysts and lesion score, compare to other infected groups. In addition, SCE-inoculated chickens with the initial infection showed a significant increase in antibody responses against SRBC and BA and also improvement in decreased relative proportions of Bu-1a(+) and CD4( )cells in cecal tonsil lymphocytes of E. tenella-challenged chickens. Cecal tissues of chickens administered SCE and initially infected with E. tenella oocysts showed lower numbers of schizonts, gametocytes and oocysts than those of infected control chickens. These results suggest that SCE have immunostimulating and protective effects against E. tenella infection in chickens. 相似文献
77.
78.
H Isogai E Isogai H Okamoto H Shirakawa F Nakamura T Matsumoto T Watanabe H Miura Y Aoi W Kagota 《Nippon juigaku zasshi. The Japanese journal of veterinary science》1989,51(6):1151-1162
The prevalence of dental disorders in dogs was studied by applying index systems for human with some modifications. A total of 251 mongrel dogs including 143 stray dogs kept in the Animal Protection Offices in Tokyo and Hokkaido and 108 pet dogs visiting veterinary clinicians in Chiba Prefecture and Hokkaido were used. Periodontitis was prevalent among these dogs regardless of their sources and its incidence was increased with age. The lesion was more severe and more frequent in the premolar and molar regions than in the maxillary and mandibular incisor regions. Missing of teeth was observed at a high and increasing incidence with age. The tooth most commonly lost was the first premolar, followed by the other premolars and molars, where severe periodontitis was frequently found. Calculus was seen on many teeth, and aging agravated its prevalence and severity. Dental caries was observed in stray dogs, but neither to a serious degree nor at a significant level. These findings emphasize the necessity of dental hygiene, proper dental care and continuous periodical survey for dogs. 相似文献
79.
Yohei Nakamura Masahiro Horinouchi Mitsuhiko Sano Takuro Shibuno 《Fisheries Science》2009,75(6):1401-1408
Whilst the importance of seagrass beds as nurseries for coral reef fishes has been clearly recognized, the vast majority of
early studies on fish nursery habitats emphasized the close proximity of the latter to coral reefs. To determine the potential
nursery role of isolated seagrass beds, we investigated the degree to which juvenile emperor fishes (Lethrinidae) utilized
seagrass beds in the presence/absence of adjacent coral habitats at Ishigaki Island (southern Japan), such fishes being known
to use seagrass beds as nurseries. Seagrass beds in close proximity to coral habitats (distance between the two habitats of
50–200 m) had greater densities of lethrinid juveniles than those without adjacent coral habitats (2.5–4 km) for 3 different
sites investigated, although a significant difference was obtained only for 1 site. Juveniles of Lethrinus atkinsoni, L. obsoletus, L. harak, and L. nebulosus were observed in seagrass beds with and without adjacent coral habitats, whereas L. ornatus occurred only in the former. Overall, most lethrinid juveniles utilize seagrass beds irrespective of the presence of adjacent
adult coral habitat, suggesting that both types of seagrass beds would contribute to lethrinid adult populations. Therefore,
management efforts for lethrinid populations should be applied not only to contiguous coral-seagrass habitat systems but also
to isolated habitats. 相似文献
80.
The activities of the enzymes involved in the malate-aspartate shuttle were measured in peripheral leucocytes of dogs with type 1 diabetes mellitus. In the diabetic dogs, fasting plasma glucose concentrations were twofold greater than control levels despite insulin injections and the activities of malate dehydrogenase (MDH), which plays a crucial role in the malate-aspartate shuttle, were decreased remarkably. The cytosolic ratio of MDH/lactate dehydrogenase (LDH) activity (M/L ratio) in leucocytes of the diabetic dogs was significantly lower than that of normal control dogs. The decrease of the M/L ratio appeared to reflect depression of energy metabolism in leucocytes of the diabetic dogs. The M/L ratio may be a useful parameter to evaluate metabolic conditions in diabetic dogs. 相似文献