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991.
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Sap water is distributed and utilized through xylem conduits, which are vascular networks of inert pipes important for plant survival. Interestingly, plants can actively regulate water transport using ion-mediated responses and adapt to environmental changes. However, ionic effects on active water transport in vascular plants remain unclear. In this report, the interactive ionic effects on sap transport were systematically investigated for the first time by visualizing the uptake process of ionic solutions of different ion compositions (K+/Ca2+) using synchrotron X-ray and neutron imaging techniques. Ionic solutions with lower K+/Ca2+ ratios induced an increased sap flow rate in stems of Olea europaea L. and Laurus nobilis L. The different ascent rates of ionic solutions depending on K+/Ca2+ ratios at a fixed total concentration increases our understanding of ion-responsiveness in plants from a physicochemical standpoint. Based on these results, effective structural changes in the pit membrane were observed using varying ionic ratios of K+/Ca2+. The formation of electrostatically induced hydrodynamic layers and the ion-responsiveness of hydrogel structures based on Hofmeister series increase our understanding of the mechanism of ion-mediated sap flow control in plants. 相似文献
993.
Solar Cells: p‐Type CuI Islands on TiO2 Electron Transport Layer for a Highly Efficient Planar‐Perovskite Solar Cell with Negligible Hysteresis (Adv. Energy Mater. 5/2018) 下载免费PDF全文
994.
Ryu Osaka Temma Ichizono Daisuke Kageyama Masashi Nomura Masayoshi Watada 《Symbiosis (Philadelphia, Pa.)》2013,60(2):73-78
A bacterium belonging to the genus Spiroplasma, an endosymbiont of the fly Drosophila hydei, is vertically transmitted through host egg cytoplasm. To infer vertical transmission rates of Spiroplasma in natural populations of D. hydei, the infection status of Spiroplasma was examined for offspring produced by Spiroplasma-positive females that were collected in two geographical populations. In both populations, nearly half of the broods consisted of only infected offspring. Infection frequencies of the rest of the broods ranged from 0.364 to 0.975. Quantitative PCR demonstrated that the Spiroplasma titers in the whole body of wild-caught females were highly variable (1.81?×?106–5.60?×?108 cells per insect). Contrary to our expectations, however, the Spiroplasma titers did not account for the variation in infection frequencies among offspring (i.e., vertical transmission rates). These results suggest that the spatial distribution of Spiroplasma, particularly in somatic tissues and germ tissues, is highly variable among host individuals, which may be caused by environmental stochasticity or some unknown effects. 相似文献
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C. Murakami N. Dohi M. Fukae T. Tanabe Y. Yamakoshi K. Wakida T. Satoda O. Takahashi M. Shimizu O. H. Ryu J. P. Simmer T. Uchida 《Histochemistry and cell biology》1997,107(6):485-494
Our previous report identified 27- and 29-kDa calcium-binding proteins in porcine immature dental enamel. In this study we
revealed that the N-terminal amino acid sequences of the two proteins were identical: LLANPXGXIPNLARGPAGRSRGPPG. The sequence
matches a portion of the amino acid sequence of the porcine sheath protein, sheathlin. Porcine tooth germs were investigated
immunochemically and immunohistochemically using specific antibodies raised against synthetic peptide that included residues
13–25 of this sequence. The affinity-purified antibodies reacted with several proteins extracted from newly formed immature
enamel in immunochemical analyses, especially protein bands migrating at 62, 35–45, 29, and 27 kDa in SDS-polyacrylamide gels.
The largest protein detected was a weak band near 70 kDa. In immunochemical analyses of proteins extracted from the inner
(old) immature enamel, the antibody reacted faintly with the 27- and 29-kDa proteins. In immunohistochemical preparations,
the Golgi apparatus and secretory granules of the secretory ameloblast, and the surface layer of immature enamel showed immunoreactivity.
The immunoreactivity of immature enamel just beneath the secretory face of the Tomes’ process was intense. No immunoreactivity
was found in the Golgi apparatus of the maturation ameloblast. These results suggest that the 70-kDa protein, whose degradation
might be very fast, is the parent protein of the 27- and 29-kDa proteins.
Accepted: 20 January 1997 相似文献
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Dayeong Jeong Chungmin Han Inhye Kang Hyun Taek Park Jiyoon Kim Hayoung Ryu Yong Song Gho Jaesung Park 《PloS one》2016,11(2)
The effects of concentrated fibroblast-conditioned media were tested to determine whether hepatocyte function can be maintained without direct contact between hepatocytes and fibroblasts. Primary rat hepatocytes cultured with a concentrated conditioned media of NIH-3T3 J2 cell line (final concentration of 55 mg/ml) showed significantly improved survival and functions (albumin and urea) compared to those of control groups. They also showed higher expression levels of mRNA, albumin and tyrosine aminotransferase compared to hepatocyte monoculture. The results suggest that culture with concentrated fibroblast-conditioned media could be an easy method for in vitro maintenance of primary hepatocytes. They also could be contribute to understand and analyze co-culture condition of hepatocyte with stroma cells. 相似文献