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151.
T Momoi S Miyagawa-Tomita S Nakamura I Kimura M Momoi 《Biochemical and biophysical research communications》1992,187(1):245-253
The expression of MyoD1 in myogenic cells located in the muscle prospective region of the limb bud at stage 20-22 was highly sensitive to retinoic acid. Unlike RAR-beta, the expression of MyoD1 mRNA in the muscle precursor cells was significantly increased by retinoic acid at lower concentrations (0.1-10 nM), but inhibited by it at higher concentrations (0.1-1 microM). The ambivalent modulation of MyoD1 expression suggested that MyoD1 expression is regulated by not only the retinoic acid receptor and its response element, but also by other factors. Retinoic acid may be involved in the differentiation of the myogenic cells during early development. 相似文献
152.
Y Chatani A Itoh E Tanaka A Hattori T Nakamura M Kohno 《Biochemical and biophysical research communications》1992,185(3):860-866
We have examined the hepatocyte growth factor (HGF)-mediated changes in protein-tyrosine phosphorylation in mouse keratinocytes (PAM-212) and canine kidney epithelial cells (MDCK). In PAM-212 cells HGF and epidermal growth factor, both of which stimulated the DNA synthesis, rapidly induced the tyrosine phosphorylation of two 41-kDa and two 43-kDa proteins: increased tyrosine phosphorylation of those proteins has been commonly observed when quiescent fibroblasts are stimulated with a variety of mitogenic agents. In contrast, HGF did not stimulate the DNA synthesis but induced cell dissociation in MDCK cells; under this condition, increased tyrosine phosphorylation of the 41-kDa and 43-kDa protein was not observed. A possible role of the increased tyrosine phosphorylation of 41-kDa and 43-kDa protein in the signaling pathway of HGF is discussed. 相似文献
153.
K Ishibashi S Sasaki H Sakamoto Y Hoshino T Nakamura F Marumo 《Biochemical and biophysical research communications》1992,187(3):1454-1459
The renal expressions of the receptor gene (c-met) for hepatocyte growth factor (HGF) were examined in unilateral nephrectomy (UNX), renal ischemia or folic acid administration. The levels of c-met mRNA were increased rapidly in all rat models at 6h after the operations. On the other hand, the expression of c-met mRNA in a kidney cell line (MDCK cells) was down-regulated for 8 h after HGF addition, indicating that c-met mRNA induction in rat models may be independent of the stimulated production of HGF. The stimulated expression of c-met in these models suggest that HGF may play an important role in renal hypertrophy after UNX and regeneration after ischemic or nephrotoxic injury. 相似文献
154.
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157.
Kaoru Nakamura Takehiko Miyai Kiyoko Inoue Seiji Kawasaki Shinzaburo Oka Atsuyoshi Ohno 《Biocatalysis and Biotransformation》1990,3(1):17-24
Esters of 3-methyl-2-oxobutanoic acid are reduced with bakers' yeast by three methods: free bakers' yeast in water, immobilized bakers' yeast in water, and immobilized bakers' yeast in hexane. Although (R)-hydroxy esters are obtained in all cases, the enantiomeric excess varies from 3% (reduction of the methyl ester with free bakers' yeast in water) to 93% (reduction of the butyl ester with immobilized bakers' yeast in hexane) depending on the structure of substrate and on the reaction conditions. The mechanism of the present stereochemical control is discussed. 相似文献
158.
Takashi Kamaishi Tetsuo Hashimoto Yoshihiro Nakamura Fuminori Nakamura Shigenori Murata Norihiro Okada Ken-ichi Okamoto Makoto Shimizu Masami Hasegawa 《Journal of molecular evolution》1996,42(2):257-263
Partial regions of the mRNA encoding a major part of translation elongation factor 1 (EF-1) from a mitochondrion-lacking protozoan,Glugea plecoglossi, that belongs to microsporidians, were amplified by polymerase chain reaction (PCR) and their primary structures were analyzed. The deduced amino acid sequence was highly divergent from typical EF-1's of eukaryotes, although it clearly showed a eukaryotic feature when aligned with homologs of the three primary kingdoms. Maximum likelihood (ML) analyses on the basis of six different stochastic models of amino acid substitutions and a maximum parsimony (MP) analysis consistently suggest that among eukaryotic species being analyzed,G. plecoglossi is likely to represent the earliest offshoot of eukaryotes. Microsporidians might be the extremely ancient eukaryotes which have diverged before an occurrence of mitochondrial symbiosis.
Sequence availability: The nucleotide sequence data reported here appear in the GSDB, DDBJ, EMBL, and NCBI databases with the accession number D32139 相似文献
159.
柑桔果实中柠檬苦素类化合物的研究现状与展望 总被引:17,自引:0,他引:17
柠檬苦素类似物(limonoid)是三萜类的植物次生代谢产物,主要存在于芸香科和楝科植物中。柠檬苦素(limonin)及其类似物存在于柑桔属(Citrus)的多种植物中。至今已从柑桔属植物中分离出36种柠檬苦素类似物及17种柠檬苦素类似物配糖体。柑桔中苦味原因之一为柠檬苦素类似物。作为其代表具有强烈苦味的柠檬苦素和诺米林如果在柑桔果汁中含量超过6mg/L,那么这种柑桔用于饮食业已不适合[1]。近年来,笔者对柑桔果实中的柠檬苦素类似物的生理变化及生物合成作过系统研究[1~9],并提出将柠檬苦素类似… 相似文献
160.
T. Matsunaga H. Sudo H. Takemasa Y. Wachi N. Nakamura 《Applied microbiology and biotechnology》1996,45(1-2):24-27
The cyanobacterium, Aphanocapsa halo-phytia MN-11, was immobilized in calcium alginate gel and coated on light-diffusing optical fibers (LDOF) for sulfated extracellular
polysaccharide production. Results indicated that sulfated extracellular polysaccharide production depends on the number of
immobilized cells and the light intensity. In addition, the production rate reached 116.0 mg (mg dry cells)-1 day-1 when the cells that were immobilized on LDOF were incubated under a light intensity of 1380 cd sr m-2 at a cell concentration of 1.0×108 cells/cm3 gel. Cells immobilized on LDOF produced about ten times more sulfated extracellular polysaccharide than those immobilized
in calcium alginate beads only (11.7 mg(mg dry cells)-1 day-1).
Received: 31 March 1995/Revised last revision 12 June 1995/Accepted 26 July 1995 相似文献