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131.
K. Wakasa J. M. Widholm 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1987,74(1):49-54
Summary Cell lines resistant to tryptophan analogue 5-methyltryptophan (5MT) were selected in seed-derived calli of Oryza sativa L. var. Norin 8. Plants were regenerated (R1 from one selected callus line (MTR1). In three out of the six R1 plants, 5MT resistance was inherited in the R2 and R3 generations as a dominant nuclear mutation. Segregation ratios in the progeny of heterozygous plants were 11. Morphological and fertility variation seen in some of the R2 plants were not correlated with 5-methyltryptophan resistance. Resistance in the MTR1 callus was due to the accumulation of high levels of free tryptophan (87-fold) that was associated with an increase in free phenylalanine content (9-fold). The leaves of resistant plants also contained elevated levels of free tryptophan and phenylalanine.Abbreviations 2,4-D
2,4-dichlorophenoxyacetic acid
- MS
Murashige and Skoog (1962) basal medium
- 5MT
D,L-5-methyltryptophan
- phe
phenylalanine
- trp
tryptophan
- tyr
tyrosine 相似文献
132.
133.
Endothelial progenitor cells (EPCs) are a subset of the total mononuclear cell population (tMNCs) that possess an enhanced potential for differentiation within the endothelial‐cell lineage. Typically, EPCs are selected from tMNCs via the expression of both hematopoietic stem‐cell markers and endothelial‐cell markers, such as CD34, or by culturing tMNCs in media selective for endothelial cells. Both EPCs and tMNCs participate in vascular growth and regeneration, and their potential use for treatment of myocardial injury or disease has been evaluated in early‐phase clinical studies. Direct comparisons between EPCs and tMNCs are rare, but the available evidence appears to favor EPCs, particularly CD34+ cells, and the potency of EPCs may be increased as much as 30‐fold through genetic modification. However, these observations must be interpreted with caution because clinical investigations of EPC therapy are ongoing. We anticipate that with continued development, EPC therapy will become a safe and effective treatment option for patients with acute myocardial infarction or chronic ischemic disease. J. Cell. Physiol. 219: 235–242, 2009. © 2008 Wiley‐Liss, Inc. 相似文献
134.
Haruki Ochi 《Environmental Biology of Fishes》1986,17(2):117-423
Synopsis The reproductive behavior of damselfish,Chromis notata, was studied at Mukaishima Island, Seto Inland Sea of Japan. Spawning occur synchronously among the fish in the study area except during a part of the breeding season. Neither spawnings nor hatchings, however, coincide with any particular phase of the lunar or tidal cycle. The intervals between the spawning peaks vary considerably during the breeding season. These results support the hypothesis that synchrony of breeding is facilitated by social interactions among the fish of a local area. The male inter-spawning intervals, and even the intervals between last spawning and next nesting, are longer than the female inter-spawning intervals in the beginning of breeding season. This delay of male spawning is attributed to the long incubation period and may have an influence on the male reproductive success. 相似文献
135.
Haruki Yamada Toshiro Yadomae Toshio Miyazaki 《Biochimica et Biophysica Acta (BBA)/General Subjects》1974,362(1):167-174
The three intra- and extracellular polysaccharide fractions were isolated during the growth phase of Dictyostelium discoideum NC-4, and the change in content of component sugars of four fractions during the culture period was examined. Myxamoebae most extensively contain a polysaccharide fraction extracted with phenol-water (polysaccharide fraction I) in a quantity of about 15–23% per dry cell. After 15 h the uronic acid formed in the polysaccharide fraction I, and the cell, could be aggregated. The glucosamine content in the polysaccharide fraction I reached a maximum as the myxamoebae entered the exponential phase, and a large amount of galactose was produced as the cell entered the stationary phase. The phenol-water extract from the cells of the stationary phase was reacted with concanavalin-A. 相似文献
136.
Kiyoshi Asai Haruki Kato Shigeru Kimura Shigehiko Mukai Yutaka Kawahito Hajime Sano Motoharu Kondo Keiko Akaogi K. Hirose 《Cancer immunology, immunotherapy : CII》1996,42(5):275-279
We have elucidated the direct effects of PSK (a protein-bound polysaccharide) and OK-432 (a streptococcal preparation), both
immunomodulating drugs, on the gene expression for an inducible nitric oxide synthase and on the production of nitric oxide
(NO) in the RAW264.7 murine macrophage cell line. As determined by northern blot analysis, both immunomodulating drugs were
potent inducers of gene expression for inducible NO synthase when cells were costimulated with interferon-γ (IFNγ). Expression
of mRNA for the enzyme occurred in a dose-dependent manner after 3 h, when 10 – 50 μg/ml PSK or 0.001 – 1 KE/ml OK-432 was
used. Furthermore, NO was also produced in response to these drugs, as detected by the Griess reagent reaction. The enhancement
of NO synthesis was thought to be mediated, in part, through tumor necrosis factor α (TNFα) induction by these agents, since
a neutralizing antibody to TNFα significantly suppressed NO production in RAW264.7 cells stimulated with PSK or OK432 in combination
with IFNγ. We speculate that NO production may play a role in tumoricidal and microbicidal activities of PSK or OK-432 in
vivo.
Received: 9 August 1995 / Accepted: 1 April 1996 相似文献
137.
For production of active proteins using heterologous expression systems, refolding of proteins from inclusion bodies often creates a bottleneck due to its poor yield. In this study, we show that molecularly imprinted polymer (MIP) toward native lysozyme promotes the folding of chemically denatured lysozyme. The MIP, which was prepared with 1 M acrylamide, 1 M methacrylic acid, 1 M 2-(dimethylamino)ethyl methacrylate, and 5 mg/mL lysozyme, successfully promoted the refolding of lysozyme, whereas the non-imprinted polymer did not. The refolding yield of 90% was achieved when 15 mg of the MIP was added to 0.3 mg of the unfolded lysozyme. The parallel relationship between the refolding yield and the binding capacity of the MIP suggests that MIP promotes refolding through shifting the folding equilibrium toward the native form by binding the refolded protein. 相似文献
138.
Haruki Takahashi 《Mycoscience》2007,48(6):342-357
Eight new species of the genus Mycena (Agaricales) found on dead leaves or twigs in warm temperate lowland forests are described and illustrated from central Honshu,
Japan: (1) Mycena fonticola sp. nov. (section Fragilipedes); (2) Mycena intersecta sp. nov. (section Fragilipedes); (3) Mycena lanuginosa sp. nov. (section Fragilipedes); (4) Mycena mustea sp. nov. (section Fragilipedes); (5) Mycena multiplicata sp. nov. (section Mycena); (6) Mycena nidificata sp. nov. (section Hiemales); (7) Mycena fuscoaurantiaca sp. nov. (section Fragilipedes); and (8) Mycena clariviolacea sp. nov. (section Fragilipedes). 相似文献
139.
Haruki Takahashi 《Mycoscience》2007,48(2):90-99
Five new species of the Boletaceae (Agaricales) from Japan are described and illustrated: (1) Boletus bannaensis sp. nov. (section Luridi), forming a grayish-brown pileus and rufescent flesh, found in subtropical evergreen broad-leaved forests; (2) Leccinum rhodoporosum sp. nov., forming discolorous red pores, a whitish stipe covered overall with violet-brown to blackish-brown furfuraceous
scales and fusoid-cylindrical brown basidiospores, found in subtropical evergreen broad-leaved forests or warm-temperate Quercus-Pinus forests; (3) Pulveroboletus brunneoscabrosus sp. nov., forming a lemon-yellow pulverulent basidiomata covered overall with orange to brownish-orange appressed scales,
found in subtropical to warm temperate evergreen broad-leaved forests; (4) Rubinoboletus monstrosus sp. nov., forming a brownish-orange to yellowish-brown pileus and a very short, nonreticulate, hollow stipe, found in subtropical
evergreen broad-leaved forests; and (5) Tylopilus fuligineoviolaceus sp. nov., having a deep violet to blackish-brown pileus and brunnescent hymenophore, found in warm temperate Quercus-Castanopsis forests. 相似文献