排序方式： 共有54条查询结果，搜索用时 15 毫秒
21.
22.
Wei W Kakizawa S Jung HY Suzuki S Tanaka M Nishigawa H Miyata S Oshima K Ugaki M Hibi T Namba S 《Phytopathology》2004,94(7):683-686
ABSTRACT Antisera raised against phloem-limited phytoplasmas generally react only with the phytoplasma strain used to produce the antigen. There is a need for an antiserum that reacts with a variety of phytoplasmas. Here, we show that an antiserum raised against the SecA membrane protein of onion yellows phytoplasma, which belongs to the aster yellows 16S-group, detected eight phytoplasma strains from four distinct 16S-groups (aster yellows, western X, rice yellow dwarf, and elm yellows). In immunoblots, approximately 96-kDa SecA protein was detected in plants infected with each of the eight phytoplasmas. Immunohistochemical staining of thin sections prepared from infected plants was localized in phloem tissues. This antiserum should be useful in the detection and histopathological analysis of a wide range of phytoplasmas. 相似文献
23.
Kirihata Y Kawarabayashi T Imanishi S Sugimoto M Kume S 《The Journal of reproduction and development》2008,54(1):35-41
In this study, we investigated the effects of administration of coumestrol during pregnancy on calcium (Ca) metabolism in post-delivery maternal and neonatal mice. From 6.5 to 16.5 days post coitus (dpc), pregnant females were administered daily doses of coumestrol (200 microg/kg body weight/day). One day after parturition, blood samples and the kidneys, liver, jejunum and duodenum were obtained from each of maternal mouse, and blood samples and the kidneys and liver were obtained from neonatal mice. Coumestrol did not have any significant effect on the Ca and inorganic phosphorus concentrations in the sera of the maternal and neonatal mice. No notable effects of coumestrol were observed in relation to Vitamin D receptor expression in the maternal and neonatal mice by immunohistochemical analysis. Coumestrol did not affect the Vitamin D receptor and epithelial calcium channel and 2 mRNA levels in any of the organs investigated. Enzyme histochemical analysis showed that coumestrol decreased intestinal alkaline phosphatase activity in the maternal jejunum and duodenum. In the duodenum, coumestrol decreased expression of intestinal alkaline phosphatase, c-fos and vascular endothelial growth factor at the mRNA level. However, we did not observe any significant effects of coumestrol on the expression of these genes. In conclusion, coumestrol decreased intestinal alkaline phosphatase activity in the small intestines of maternal mice at the level used in the present study, and the mechanisms underlying this effect are different for the jejunum and duodenum. 相似文献
24.
We investigated seasonal patterns of water relations in current-year leaves of three evergreen broad-leaved trees (Ilex pedunculosa Miq., Ligustrum japonicum Thunb., and Eurya japonica Thunb.) with delayed greening in a warm-temperate forest in Japan. We used the pressure-volume method to: (1) assess the extent to which seasonal variation in leaf water relations is attributable to leaf development processes in delayed greening leaves versus seasonal variation in environmental variables; and (2) investigate variation in leaf water relations during the transition from the sapling to the adult tree stage. Leaf mass per unit leaf area was generally lowest just after completion of leaf expansion in May (late spring), and increased gradually throughout the year. Osmotic potential at full turgor (Psi(o) (ft)) and leaf water potential at the turgor loss point (Psi(w) (tlp)) were highest in May, and lowest in midwinter in all species. In response to decreasing air temperature, Psi(o) (ft) dropped at the rate of 0.037 MPa degrees C(-1). Dry-mass-based water content of leaves and the symplastic water fraction of total leaf water content gradually decreased throughout the year in all species. These results indicate that reductions in the symplastic water fraction during leaf development contributed to the passive concentration of solutes in cells and the resulting drop in winter Psi(o) (ft). The ratio of solutes to water volume increased in winter in current-year leaves of L. japonicum and E. japonica, indicating that osmotic adjustment (active accumulation of solutes) also contributed to the drop in winter in Psi(o) (ft). Bulk modulus of elasticity in cell walls fluctuated seasonally, but no general trend was found across species. Over the growing season, Psi(o) (ft) and Psi(w) (tlp) were lower in adult trees than in saplings especially in the case of I. pedunculosa, suggesting that adult-tree leaves are more drought and cold tolerant than sapling leaves. The ontogenetic increase in the stress resistance of I. pedunculosa may be related to its characteristic life form because I. pedunculosa grows taller than the other species studied. 相似文献
25.
Katayama S Ishikawa S Fan MZ Mine Y 《Journal of agricultural and food chemistry》2007,55(8):2829-2835
Previously, we have found phosphopeptides (PPPs) from hen egg yolk phosvitin possess a potent antioxidative activity against oxidative stress in human intestinal epithelial cells, Caco-2. However, their biological activity at the cellular level has not yet fully understood. The objective of this study is to evaluate the regulation of glutathione (GSH) biosynthesis-associated and antioxidant enzymes against oxidative stress in Caco-2 cells using an in vitro model. Treatment of 1 mM H2O2-induced Caco-2 cells with PPPs increased cellular GSH levels, concomitant with a significant increase in gamma-glutamylcysteine synthetase (gamma-GCS) activity and the expression of gamma-GCS heavy subunit mRNA. Furthermore, intracellular glutathione reductase, glutathione S-transferase, and catalase activities were elevated by PPPs. In addition, PPPs with high content of phosphorus showed higher induction of these enzyme activities than PPPs without phosphorus. These data indicate that oligophosphopeptides from hen egg yolk phosvitin can up-regulate cellular GSH biosynthesis-associated enzymes activity and antioxidative activities, which play key roles against tissue oxidative stress in the human intestinal epithelial cells. 相似文献
26.
Md. Shah Alam Shin-Ichi Teshima Manabu Ishikawa Shunsuke Koshio 《Journal of the World Aquaculture Society》2000,31(4):618-626
Abstract.— Growth studies were conducted to determine the dietary methionine requirement of juvenile Japanese flounder Paralichthys olivaceus . A basal diet was formulated to contain 50% crude protein from casein and gelatin, as intact protein sources, supplemented with crystalline L-amino acids (CAA), to correspond to the amino acid pattern found in the whole body protein of the juvenile Japanese flounder, except methionine. Test diets contained six graded levels of L-methionine 0.53, 0.83, 1.13, 1.43, 1.73, and 2.03% of diet (dry matter basis) or 1.06, 1.66, 2.26, 2.86, 3.46 and 4.06% of protein. To prevent leaching losses of water-soluble amino acids, CAA were pre-coated with carboxymethylcellulose (CMC), and diets were further bound with both CMC and κ-carrageenan after addition of the pre-coated CAA. Weighing about 2.80 g, each triplicate group of the juvenile flounder were fed test diets twice a day (5% of body weight) for 40 d. Survival rate, specific growth rate, feed conversion efficiency and apparent protein retention were significantly ( P < 0.05) affected by dietary methionine concentrations. The optimum dietary level of methionine in the presence of 0.06% of dietary cystine for Japanese flounder juvenile was estimated by using break point analysis. The values determined based on weight gain and feed efficiency were 1.49% of diet (or 2.98% of protein) and 1.44% of diet (or 2.88% of protein), respectively. These requirement values are close to the methionine level of flounder whole body protein. 相似文献
27.
Toncaun Ren Shunsuke Koshio Shin-Ichi Teshima Manabu Ishikawa Md. Sham Alam Arthur Panganiban Jr. Yin Yin Moe Tomokazu Kojima Hiroyuki Tokumitsu 《Journal of the World Aquaculture Society》2005,36(4):437-443
A feeding experiment was conducted to determine the optimum dietary level of ascorbic acid (AsA) for Japanese eel juveniles using L-ascorbic acid Ca based on growth, AsA content in tissues, hematology, and bactericidal activity of serum with Escherichia coli . Test diets with six levels of AsA (3, 10, 27,126, 645, and 3,135-mg/kg diet) as Ca ascorbate were fed to juvenile Japanese eels (11.0 ± 0.2 g) once a day for 8 wk. High survival rates (> 80%) were observed among all dietary treatment groups. The specific growth rates of the fish fed diets containing 3 and 10-mg AsA/kg were significantly (P < 0.05) lower than those of other groups. Liver and brain AsA contents of the fish fed diets containing 3, 10, and 27-mg AsA/kg were significantly (P < 0.05) lower than those of the fish fed diets containing 645 and 3,135-mg AsA/kg. Hemoglobin content tended to be higher in the fish fed diets containing 645 and 3,135-mg AsA/kg than those of the fish fed other diets. Hematocrit value and total serum protein content of the fish fed diets containing 645 and 3135 mg AsA/kg were significantly (P < 0.05) higher than those of the other groups. The fish fed diets containing more than 27-mg AsAlkg showed a higher bactericidal activity of serum than the fish fed the diets containing 3-mg and 10-mg AsA/kg. The optimum dietary level of AsA for the Japanese eel juveniles growth was estimated to be more than 27-mg AsA/kg. Furthermore, the inclusion of 645-mg AsA/kg or more also increased the hematocrit, hemoglobin, total serum protein value, and liver and brain vitamin C concentrations. 相似文献
28.
Shin-Ichi Fujita Akira Takahashi Hiroshi Hayami Tatsuya Sakurai 《Water, air, and soil pollution》2001,130(1-4):415-420
Wet deposition monitoring was conducted at six rural stations in western Japan, during the period from 1987 through 1996. Long-term trends in the concentration of non-sea salt ions were analyzed on the basis of the data obtained. The monitoring results indicated that annual average concentrations of NO3 ? and NH4 + in precipitation significantly increased on the order of 45%, and that of nss-Ca2+ and nss-SO4 2?, concentrations did not change over the past 10 years. The ratio of NO3 ?/nss-SO4 2? in precipitation significantly increased, the ratio of NO3 ?/NH4 + showed no marked fluctuations, and the ratio of [nss-Ca2++NH4 +]/[nss-SO4 2?+NO3 ?] slightly increased during the period. These findings suggested that the wet deposition of NO3 ? and NH4 + in western Japan, particularly that in the winter season, was influenced by the long-range transport of nitrogen oxides and ammonia from the Asian continent. 相似文献
29.
Kang Gongunn Collett Jeffrey L. Shin Dae-Ywen Fujita Shin-Ichi Kim Hui-Kang 《Water, air, and soil pollution》2004,151(1-4):11-34
Precipitation samples were collected at two coastal sites on the Korean Peninsula, Kangwha on the western coast and Yangyang on the eastern coast, from September 1991 to February 1997. The samples were analyzed for concentrations of major ions, in addition to pH and electrical conductivity. The annual volume-weighted mean pH values were 4.89 and 5.05 at Kangwha and Yangyang, respectively. The pH was generally lower at Kangwha than that at Yangyang, especially during the winter, because of reduced neutralizing inputs and greater acid inputs in winter. Dominant ions were different with NH4 + and SO4 2- most important at Kangwha and Na+ and Cl- at Yangyang. Neglecting sea salt components, nss-SO4 2- and NO3 - were important anions and nss-Ca2+ and NH4 + were important cations at both sites. Concentrations of these ions were 1.2–1.6 times higher at Kangwha than at Yangyang. Annual mean concentrations of these ions varied little during the study, while larger seasonal variations were observed. Annual mean nss-SO4 2-/NO3 - ratios at Kangwha and Yangyang were 2.8 and 2.6. The 5 yr annual mean values of nss-SO4 2-/NO3 - showed no trend at Kangwha but a decreasing tendency at Yangyang. The decreasing trend is similar to the decreasing trend in emissions of SO2/NOx in South Korea. Regional differences in chemical composition between Kangwha and Yangyang appear to be associated with long-range transport of acidic gases and alkaline dust originated from other regions. 相似文献
30.
Kayano S Kikuzaki H Fukutsuka N Mitani T Nakatani N 《Journal of agricultural and food chemistry》2002,50(13):3708-3712
Ethanol extract of prune was separated into hexane-soluble and H(2)O-soluble fractions, and the H(2)O-soluble fraction was further separated into a methanol (MeOH) eluate and an H(2)O eluate by Diaion HP-20 column chromatography. The MeOH eluate exhibited the strongest antioxidant activity among the separated fractions evaluated by oxygen radical absorbance capacity (ORAC). Further purification of the MeOH eluate led to isolation of a novel compound, 4-amino-4-carboxychroman-2-one, together with four known compounds (p-coumaric acid, vanillic acid beta-glucoside, protocatechuic acid, and caffeic acid), structures of which were identified by NMR and MS analyses. The ORAC values of these isolated compounds showed 0.15-1.43 units (micromol of Trolox equiv)/micromol, and the new compound showed a remarkable synergistic effect on caffeoylquinic acid isomers. The antioxidant activity of the MeOH eluate was highly dependent on the major prune components, caffeoylquinic acid isomers, with a contribution from the new synergist. 相似文献