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排序方式: 共有1143条查询结果,搜索用时 789 毫秒
881.
Takeshi Kanaya Hisashi Kokubun Hitoshi Watanabe Goro Hashimoto Eduardo Marchesi Laura Bullrich Toshio Ando 《Scientia Horticulturae》2010
To evaluate and describe the current status of Calibrachoa cultivars as bedding plants, the seasonal flowering of 91 commercial cultivars were compared to those of natural species using principal components analysis. The predominant flowering of the cultivars, that is, floriferous in late spring to early summer with a tendency to reduce flower production toward winter, seems to have remained unchanged from that of natural species. However, properties desired in bedding plants, such as early flowering and continuous flowering under short-day and/or low temperature conditions, appear to have been improved in a considerable number of cultivars, although there is still room for improvement. Seasonal and total floral counts were higher in many cultivars compared to natural species. Several natural species were selected for their unique flowering ability and should be evaluated as gene resources for improving the flowering of Calibrachoa cultivars. 相似文献
882.
The decay risk of airborne wood-decay fungi was investigated by using an air sampler. Japanese cedar disks 7.8 cm in diameter
and about 3 mm in thickness with moisture content of about 100% were placed in a “BIOSAMP” air sampler and exposed to 1000
l air. Air sampling was carried out from June to September at the same sampling site in Tsukuba, Japan. The exposed disks
were then incubated for 16 weeks in a damp container kept at 26° ± 2°C. During the incubation period, wood mass loss ranged
from −15 to 807 mg with a mean mass loss of 244 mg. Factors affecting mass loss were explored. Wood moisture content and ratio
of heartwood area proved to be significant factors. In addition, six weather factors were found to influence mass loss. Disks
that were sampled on a cloudy day showed significantly higher mean mass loss compared to those sampled on a sunny day. Subculturing
of filamentous fungi from 16-week incubated disks suggested one-third of the isolated fungi produced ligninolytic enzymes. 相似文献
883.
Takeshi KAWAHARA 《Animal Science Journal》2010,81(6):714-721
This study investigated the in vitro effect of Lactobacillus strains, a major group of probiotic lactic acid bacteria, on immunoglobulin E (IgE)‐ and antigen‐induced mast cell degranulation and subsequent gene expression. Bone marrow‐derived mast cells (BMMCs) from DBA/2 mice were cultured with heat‐killed Lactobacillus strains for 24 h. Some strains significantly inhibited IgE‐ and antigen‐induced β‐hexosaminidase release from BMMCs. Furthermore, Lactobacillus reuteri NBRC 15892, which exhibited the strongest inhibitory activity, significantly reduced the elevated interleukin (IL)‐4, IL‐13, tumor necrosis factor‐α, and cyclooxygenase‐2 expression levels that was induced by 1–2 h of stimulation with IgE and antigens. The suppressive effect of NBRC 15892 strain on BMMC degranulation was significantly reduced in the presence of a toll‐like receptor (TLR)2‐neutralizing antibody. In addition, downregulation of cell surface FcεRIα expression was observed after 6 h of NBRC 15892 treatment. These results suggest that some Lactobacillus strains inhibited IgE‐mediated mast cell degranulation and subsequent late‐phase reactions involving mast cells via a TLR2‐dependent mechanism with FcεRIα downregulation. 相似文献
884.
Yamamoto T 《Marine drugs》2010,8(11):2781-2794
Sialyltransferases transfer N-acetylneuraminic acid (Neu5Ac) from the common donor substrate of these enzymes, cytidine 5'-monophospho-N-acetylneuraminic acid (CMP-Neu5Ac), to acceptor substrates. The enzymatic reaction products including sialyl-glycoproteins, sialyl-glycolipids and sialyl-oligosaccharides are important molecules in various biological and physiological processes, such as cell-cell recognition, cancer metastasis, and virus infection. Thus, sialyltransferases are thought to be important enzymes in the field of glycobiology. To date, many sialyltransferases and the genes encoding them have been obtained from various sources including mammalian, bacterial and viral sources. During the course of our research, we have detected over 20 bacteria that produce sialyltransferases. Many of the bacteria we isolated from marine environments are classified in the genus Photobacterium or the closely related genus Vibrio. The paper reviews the sialyltransferases obtained mainly from marine bacteria. 相似文献
885.
Julia Bailey-Serres Takeshi Fukao Pamela Ronald Abdelbagi Ismail Sigrid Heuer David Mackill 《Rice》2010,3(2-3):138-147
Rice landraces tolerant of up to 2 weeks of complete submergence were collected from farmers’ fields in the 1950s. Success in fine mapping of SUBMERGENCE 1 (SUB1), a robust quantitative trait locus from the submergence tolerant FR13A landrace, has enabled marker-assisted breeding of high-yielding rice capable of enduring transient complete submergence. At the molecular level, SUB1 is a variable polygenic locus encoding two or three ethylene responsive factor (ERF) DNA binding proteins. All Oryza sativa accessions encode SUB1B and SUB1C at this locus. An additional ERF, SUB1A, is present at SUB1 in FR13A and other tolerant accessions. The induction of SUB1A expression by ethylene during submergence disrupts the elongation escape strategy typical of lowland and deepwater rice, by limiting ethylene-induced gibberellic acid-promoted elongation. Microarray and metabolite studies confirm that SUB1A orchestrates its effects on metabolism and growth in a submergence-dependent manner. Due to the conditional activity of SUB1A, new “Sub1” mega-varieties effectively provide submergence tolerance without apparent ill effect on development, productivity, or grain quality. 相似文献
886.
Hiroyuki Matsunari Takeshi Yamamoto Shin-Kwon Kim Takanobu Goto Toshio Takeuchi 《Fisheries Science》2008,74(2):347-353
ABSTRACT: This study was conducted to investigate the effect of dietary taurine and cholyltaurine (C-tau) on growth and body composition of juvenile red sea bream Pagrus major . Semi-purified casein-based diets supplemented with 0 (control diet), 0.1, 0.3, 0.5 and 0.7% taurine and 0.5% C-tau were fed to red sea bream (average body weight 4.7 g) for 6 weeks at 20°C. The growth and feed efficiency were the lowest in fish fed the control diet. Taurine supplementation improved the growth and feed efficiency of fish dose-dependently, and the taurine requirement was estimated as 0.52% in terms of optimizing growth and 0.48% in terms of optimizing feed efficiency. Taurine content in the whole body and liver increased with the dietary taurine level. Supplemental C-tau at the 0.5% level had limited effects on the growth and no effect on body taurine, biliary bile salt and liver fat contents. From these results it can be inferred that the optimal dietary taurine requirement of juvenile red sea bream is 0.5% on a dry weight basis, and that the supplementation of taurine in the diet not only improves the growth but also increases hepatic lipid levels of red sea bream juveniles. 相似文献
887.
888.
889.
Pongsuwan W Bamba T Yonetani T Kobayashi A Fukusaki E 《Journal of agricultural and food chemistry》2008,56(3):744-750
A couple between pyrolyzer and gas chromatography/mass spectrometry (GC/MS) has allowed a fast, simple, and low-cost approach to evaluate a quality of Japanese green tea without any sample preparation or derivatization techniques. Using our method, errors from sample preparation could be avoided since raw samples were directly extracted through the extreme heat of the pyrolyzer. In addition, undesired reactions from expensive derivatizing agents, which are commonly needed to treat the samples before analyzing with GC/MS, could be omitted. In order to illustrate the efficiency of this technique, a set of green tea samples from the Tea contest in 2005 in the Kansai area were used. Projection to latent structure by means of partial least squares (PLS) along with orthogonal signal correction (OSC) was selected to explain the relation between green tea's metabolite profiling and its quality. The quality of the model was validated by testing and comparing the predictive ability to the respective model. 相似文献
890.
Effect of dietary omega 3 phosphatidylcholine on obesity-related disorders in obese Otsuka Long-Evans Tokushima fatty rats 总被引:1,自引:0,他引:1
Shirouchi B Nagao K Inoue N Ohkubo T Hibino H Yanagita T 《Journal of agricultural and food chemistry》2007,55(17):7170-7176
Recent reports have shown that dietary phosphatidylcholine (PC) has various beneficial biological effects. Omega 3 polyunsaturated fatty acids (omega3 PUFAs) have also been reported to have lipid-lowering effects in animal models and human studies. In the present study, we investigated the effect of omega3 PUFAs containing PC (omega3-PC) on obesity-related disorders in Otsuka Long-Evans Tokushima fatty (OLETF) rats. Rats were fed semisynthetic diets that contained either 5% corn oil and 2% egg-PC or 5% corn oil and 2% omega3-PC for 4 weeks. During this 4 week feeding of the omega3-PC, the OLEFT rats showed a decrease of omental white adipose tissue weight. In addition, the omega3-PC diet significantly decreased liver weight and hepatic lipid levels in OLETF rats. These changes were attributable to the significant suppression of fatty acid synthase activity and significant enhancement in the activities of carnitine palmitoyltransferase and peroxisomal beta-oxidation. Moreover, the omega3-PC diet reduced serum glucose levels concomitant with the increase of serum adiponectin levels. These results show that compared with egg-PC, omega3-PC can prevent or alleviate obesity-related disorders through the suppression of fatty acid synthesis, enhancement of fatty acid beta-oxidation, and increase of the serum adiponectin level in OLETF rats. 相似文献