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排序方式: 共有634条查询结果,搜索用时 15 毫秒
11.
Hisayuki Arakawa Yohei Ohi Akira Matsumoto Kenji Takio Takumi Kimoto Katsutoshi Kawabe 《Fisheries Science》2012,78(5):1083-1090
The populations of red alga Gelidium elegans along the coast of Miyakejima Island were severely damaged by a volcanic eruption in 2000. The effect of this volcanic eruption has been long lasting, and populations of this red alga still have not recovered. We investigated the effect of seabed sediment particles derived from volcanic ash on the substrate adhesion of G.?elegans spores. The analysis provides evidence that increasing amounts of sediment particles result in lower adhesion rates of G.?elegans spores, and that smaller sediment particles have a greater influence on adhesion. The amount of seabed sediment particles around Miyakejima Island was 9.3?C1815.4?mg/cm2. This amount has changed greatly from year to year. The adhesion rate of G.?elegans spores in water around Miyakejima Island was 0?% at all points in 2008 and 2010, but it was estimated as 6.3?C38.6?% in 2009. These results suggest that there is significant inhibition of algal spore adhesion by seabed sediment particles derived from volcanic ash around Miyakejima Island. 相似文献
12.
The critical Na levels in soil which restricted seed germination and growth of radish, and effect of the amending materials on reducing the salinity hazard were determined by performing petri dish and pot experiments. The plants were grown in amended salinized soil in a phytotron for 21 days. Excess accumulation of Na in cells suppressed seed germination and plant growth. The critical Na level in control soil which restricted germination and growth was 12.5mg Na/g soil. At the same salinity level, amending materials promoted seed germination and plant growth mainly by inhibiting the excess flow of Na into the cell through ion holding mechanism. Among the materials used, the commercial manure of 4 months old held greater amount of Na(3.7mg/g) and thus more efficiently reduced the ion damage. Plants grown under such treatment had the highest dry matter yield (28.Gmg/plant), water content was normal(84%), and the ratio for Na in root to Na in plant's shoot was 2.4. As for the case of plant grown in control soil the respective data were 8. 5mg, 54%, and 4.8. 相似文献
13.
Naoki Harada Shigeto Otsuka Masaya Nishiyama Satoshi Matsumoto 《Biology and Fertility of Soils》2005,41(1):46-51
A pot experiment was conducted to investigate the influences of indigenous phototrophs on methane (CH4) emissions from a paddy soil where rice straw was incorporated or was surface-applied. During the cultivation, half of the pots were covered with aluminum foil, except for the minimum space for rice plants, to prevent ambient light reaching the floodwater or the soil surface. Growth of oxygen-producing phototrophs was hardly observed in the unilluminated plots, whereas intensive growth of algae, duckweed and hydrophytes was found in the illuminated ones. Plant growth was not affected by the different treatments. Seasonal changes in CH4 emission determined by a closed chamber method indicated that illumination had no or only minor effects on CH4 emissions when rice straw was incorporated or was not applied, but significantly reduced CH4 emissions when rice straw was surface-applied. Methanogenesis occurring in the soil-floodwater interface was further investigated in two lab-scale model experiments measuring methanogenic activity. As a result, more activated methanogenesis was found in the surface-applied rice straw and the soil around the straw compared with the soil incubated without rice straw. The magnitude of the methanogenic activity in the rice straw incubated under illuminated conditions was significantly lower than that incubated in the dark. Consequently, this study demonstrates that methanogenesis in paddy soil occurs even in the soil-floodwater interface if plant residues like rice straw exist, and such methanogenesis is likely to be suppressed by growth of indigenous phototrophs under illumination. 相似文献
14.
Fatemeh Abbasi Mina Taghizadeh Babak ValizadehKaji 《International Journal of Fruit Science》2019,19(2):221-230
Prunus scoparia is a wild deciduous shrub, usually living on dry calcareous soils of the rocky mountains and has been used as a grafting rootstock for domesticated almonds to provide drought resistance. In the current study, micropropagation ability of P. scoparia was investigated using cytokinin and auxin. Uniform nodal shoot pieces (3–5 cm in length) of seedlings were used as explants. The explants were disinfected with 10% sodium hypochlorite solution. For adventitious shoot induction and proliferation, Murashige and Skoog (MS) media containing 7.00 g/l agar and 30.00 g/l sucrose containing five concentrations of benzyl adenine (BA) (0.00, 0.50, 1.00, 2.00, and 4.00 mg/1) and also containing six concentrations of Thidiazuron (TDZ) (0.00, 0.50, 1.00, 2.00, 5.00, and 7.00 mg/1) were compared. For rooting, in vitro shoots (2–3 cm) were transferred into ½ MS medium supplemented with 30 g/l sucrose, 7.50 g/l agar, and different concentrations of IBA (0.00, 0.25, 0.50, and 1.00 mg/l) and NAA (0.00, 0.25, 0.50, and 1.00 mg/l). Based on the results obtained for shoot proliferation, only 2.00 and 4.00 mg/l BA and 2.00 mg/l TDZ concentrations generated shoots, while other treatments did not show shoot proliferation. Among the three treatments that generated shoots, the best results for shoot number, leaf number, and leaf color quality were observed in media containing 2.00 mg/l TDZ. Based on the results obtained for rooting, the effect of IBA concentrations on the rooting percentage, root number, and root length was significant. Among IBA concentrations, only 0.50 mg/l IBA induced rooting, while there was no rooting in the media containing other IBA concentrations. None of the NAA concentrations showed rooting. In conclusion, MS culture medium supplemented with 2.00 mg/l TDZ and ½ MS culture medium supplemented with 0.50 mg/l IBA are suggested for in vitro shoot proliferation and rooting of P. scoparia, respectively. The results presented herein could be used for in vitro selection and micropropagation of P. scoparia. 相似文献
15.
In trace metal (TM)-contaminated agricultural soils, management of TM availability is important for safe crop production. In addition, maintenance or improvement of soil quality is vital for sustainable crop cultivation. Decreased TM phytoavailability and increased soil quality can be achieved by the application of various immobilizing agents to soil, which can supply both macronutrients and organic matter. This study investigated the long-term influences of four common immobilizing agents on so... 相似文献
16.
Yabuki A Maeda M Suzuki S Matsumoto M Kurohmaru M Hayashi Y Taniguchi K Nishinakagawa H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(4):461-465
Although mice kidney morphology shows various sexual dimorphisms, the effect of the estrous cycle has not previously been discussed. In this study, we investigated the effects of the estrous cycle on kidney morphology, including renin-positive areas, of female DBA/2 mice. No effects were confirmed in most of the histometrical parameters, however, the percentage of the renal corpuscles in which cuboidal epithelium covered under 50% of the parietal layer was significantly higher during estrus compared to that during anestrus. 相似文献
17.
Immunogenicity of a soluble antigen against Pasteurella haemolytica-associated pneumonia in calves 总被引:3,自引:0,他引:3
M Matsumoto J A Schmitz B Syuto B J Watrous D E Mattson 《Veterinary research communications》1984,8(2):117-130
Three experiments were performed to evaluate the immunogenic potency of a soluble fraction of Pasteurella haemolytica against pneumonic pasteurellosis in calves. A soluble antigen was extracted by a 2.5% saline solution from P. haemolytica. Weaned Holstein bull calves, seronegative for infectious bovine rhinotracheitis virus ( IBRV ) and the pasteurella antigen, were vaccinated either by repeated subcutaneous (SC) vaccination, or by exposure 3 times to the aerosol of P. haemolytica antigen. Challenge exposure to aerosol of P. haemolytica was preceded by infection with IBRV , or in experiments 2 and 3, the virus exposures were combined with a stress treatment. The lung lesions were examined at necropsy 3 to 8 days post infection. In the first experiment, all the vaccinated calves produced specific antibody response to the pasteurella antigen, and none of the calves including controls showed significant lesions in the lung. In the second experiment 2 aerogenically vaccinated calves had no lesions. One of the two SC-vaccinated calves had mild consolidated lesions. Two control calves, one of which died 3 days following the challenge, developed severe fibrinous pneumonia with consolidation of 50% or more of the lung surfaces. P. haemolytica was isolated only from the 2 control animals. In the third experiment, 2 of the 3 control calves developed moderate to severe consolidation, but P. haemolytica was isolated only from one of them. Two of the three aerosol-vaccinated calves also developed significant lesions and one of them yielded the bacteria from the lung. Three SC-vaccinated calves had slight lesions and the organism was not isolated from their lungs. The results did not consistently indicate an immunogenic potential of the soluble antigen against P. haemolytica-related pneumonia. The effect of stress on the pathogenesis of bovine viral pneumonia and correlation between pneumonic lesions and antibacterial resistance in situ are discussed. 相似文献
18.
Matsumoto K Inokuma H Okuda M Onishi T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(1):137-140
The effects of salivary gland extract (SGE) from R. sanguineus were examined on the production of IgG1 and IgG2 and the mRNA expression of IFN-gamma, IL-2, IL-4, IL-5 and IL-10 in the mononuclear cells from canine peripheral blood, treated with concanavalin A (ConA) in vitro. SGE suppressed the ConA-induced production of IgG2. It also inhibited the expression of IFN-gamma, IL-2 and IL-5 mRNA in a dose-dependent manner. No dose-dependent suppression was observed of IL-10 mRNA expression although a significant effect was observed at a SGE protein concentration of 25 microg/ml. SGE had no effect on the mRNA expression of IL-4. These results suggest that the suppression of IgG2 production by SGE from R. sanguineus was caused by the suppression of IFN-gamma production. 相似文献
19.
Kaneki K Kanouchi H Matsumoto M Kawasaki Y Akuzawa M Oka T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(7):781-785
Perchloric acid-soluble protein (PSP) is a members of a new hypothetical family (YER057c/YJGF family) of small proteins with presently unknown function. The high degree of evolutionary conservation of these proteins reflect an involvement in basic cellular regulation. The expression of PSP was examined in rat hepatoma cell dRLh 84-beared rats. The tumor weight increased to 4.24 g at 3 weeks after the transplantation of hepatoma cells and hepatoma which has less differentiated characteristics were observed in rat liver. The expression of PSP in rat hepatoma was down regulated as compared with intact tissue. Thus the expression of PSP seems to be associated with the differentiation process in these transformed cells. On the other hand, some positive cells against the PSP-antibody were observed in the central region of tumor tissue by immunohistochemistry. These cells were shown to be the lymphocytes and the macrophages. The involvement of PSP to cellular growth and differentiation is discussed. 相似文献
20.
Kawai S Matsumoto J Aikawa M Matsuda H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(5):629-631
In the present study, we investigated plasma levels of soluble intercellular adhesion molecule-1 (sICAM-1) and vascular cell adhesion molecule-1 (sVCAM-1) in seven Japanese macaques (Macaca fuscata) infected with Plasmodium coatneyi. Concentrations of sICAM-1 and sVCAM-1 were significantly elevated in the severe phase; the levels were maximally increased up to six times and three times those before infection, respectively. We subsequently examined kinetic profiles of sICAM-1 and sVCAM-1 concentration in plasma obtained from two infected monkeys. Both infected monkeys had markedly increased levels of these adhesion molecules when they exhibited severe clinical signs correlated with rapid increase in parasitemia. These results suggest that the elevation of levels of sICAM-1 and sVCAM-1 is a critical step in the pathogenesis of severe malaria in vivo. 相似文献