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The mRNA expression of GPRC5B, an orphan G protein-coupled receptor, is induced by retinoic acid (RA). Because RA plays critical roles in embryonic development, reproductive functions, metabolism and homeostasis, GPRC5B is also considered crucial in these physiological events. We investigated the changes in expression of GPRC5B and RA receptor (RAR) alpha mRNAs and immunohistochemical localization of their proteins in the murine placenta and yolk sac at 13.5, 15.5 and 17.5 days post coitus. Stable levels of GPRC5B and RARalpha mRNAs were detected in the placenta and yolk sac. In the placenta, GPRC5B was present in maternal and fetal vascular endothelial cells, stromal cells, fibroblast-like cells and glycogen cells. A strong reaction to RARalpha was detected in maternal and fetal vascular endothelial cells and stromal cells. The levels of GPRC5B and RARalpha proteins in maternal and fetal vascular endothelial cells decreased with gestation. In the yolk sac, GPRC5B and RARalpha proteins were detected in vascular endothelial cells, but their levels did not change during the gestation period. These findings indicate that GPRC5B is involved in RA-dependent morphogenesis/angiogenesis and regulation of extracellular matrix synthesis in the murine placenta and yolk sac.  相似文献   
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H. M. Kamal    T. Takashina    H. Egashira    H. Satoh  S. Imanishi 《Plant Breeding》2001,120(2):179-181
This study was performed to introduce the distinct aromatic fragrance of Lycopersicon peruvianum LA 1554 into the cultivated tomato, Lycopersicon esculentum. The strong breeding barriers existing between these two distantly related species were circumvented by the ovule selection and culture method. A large BC1F1 population was developed and among 127 plants, 36 were self‐compatible and yielded fruits. Fruits of some of these selected plants were found to be enriched with a sweet aromatic flavour. Sensory evaluation of the fruit aroma of these selected plants was performed by a panel of 12 members against one of the best consumer‐rated Japanese commercial tomato cultivars, ‘Momotaro’. Although extensive variation was observed in fruit‐aroma in the BC1F1 population, panel opinion on ‘flavour‐desirability’ significantly favoured the BC1F1 fruits of some selected plants over the cv. ‘Momotaro’. Therefore, it can be concluded that the aromatic fragrance of a ‘L. peruvianum’ accession has successfully been introduced into the cultivated tomato gene pool.  相似文献   
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H. Egashira    R. Ogawa    H. Kanno    T. Tanisaka  S. Imanishi 《Plant Breeding》1999,118(3):253-258
To overcome the cross-breeding barriers between the cultivated tomato Lycopersicon esculentum and the ‘peruvianum-complex’, hybrid production ability (HPA) and pistillate-parental differences were investigated. As a criterion of HPA, the number of germinated ovules per fruit (GPF) was used. GPF was expressed as GPF = OPF × GPO, where OPF is the number of ovules per fruit, and GPO is the proportion of germinated ovules to total ovules obtained. The interspecific crossing between nine varieties and three ‘peruvianum-complex’ accessions revealed that the cultivars ‘Sekaiichi’,‘Ponde Rooza’ and ‘Early Pink’ showed quite high and stable GPF over the years, but the cv.‘Best of All’ produced no hybrids. Variance analysis for GPF, OPF and GPO, and their correlation with seven sexual organ morphological traits and three fruit morphological traits were performed. These results indicated that choosing both the pistillate parents with wider reproductive organs for high OPF and appropriate environmental conditions for high GPO might be significant for enhancing GPF in interspecific crossing.  相似文献   
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With high-resolution continuous gravity recordings from a regional network of superconducting gravimeters, we have detected permanent changes in gravity acceleration associated with a recent large earthquake. Detected changes in gravity acceleration are smaller than 10(-8) meters seconds(-2) (1 micro-Galileo, about 10(-9) times the surface gravity acceleration) and agree with theoretical values calculated from a dislocation model. Superconducting gravimetry can contribute to the studies of secular gravity changes associated with tectonic processes.  相似文献   
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The methanol extract from Uncaria sinensis showed a suppressive effect on umu gene expression of the SOS response in Salmonella typhimurium TA1535/pSK1002 against the mutagen 3-amino-1,4-dimethyl-5H-pyrido[4,3b]indole (Trp-P-1), which requires liver metabolizing enzymes. The methanol extract from U. sinensis was re-extracted with hexane, CH2Cl2, BuOH, and water, respectively. CH2Cl2 extract showed a suppressive effect. A suppressive compound 1 in CH2Cl2 extract was isolated by SiO2 column chromatography. Compound 1 was identified as ursolic acid by IR, electron ionization EI-MS, and NMR spectroscopy. Suppressive effects of ursolic acid (1) and its derivatives, methyl ursolate (1M), acetylursolic acid (1A), and methyl acetylursolate (1MA), were determined in the umu test. These compounds suppressed 61.3, 37.7, 71.5, and 37.8% of the Trp-P-1-induced SOS response at a concentration of 0.4 micromol/mL, respectively. The ID50 values of compounds 1 and 1A were 0.17 and 0.20 micromol/mL. In addition, these compounds were assayed with the activated Trp-P-1. Suppressive effects on activated Trp-P-1 were decreased as compared with those of Trp-P-1.  相似文献   
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In Salmonidae, subordinate males are exposed to higher risks of sperm competition than dominant males and thus are expected to improve the sperm characteristics (sperm concentrations, sperm velocity and sperm longevity). In this study, we investigated the relationships between body size and secondary sexual characters (breeding colour, hump height and snout length), and sperm characteristics of one‐year‐old (newly matured) Dolly Varden char. Small males displayed higher sperm concentrations than large males. Moreover, males with dull breeding colours, but not with lesser snout length and hump height, displayed an increased sperm velocity compared to males with bright colours, suggesting a trade‐off between sperm quantity and the investment in breeding colour. In addition, sperm longevity decreased as sperm swimming velocity increased. These findings indicate that small males with dull breeding colours improve the quantity and quality of their sperm to a great extent to enhance their chances of reproductive success.  相似文献   
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