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461.
Tension wood was induced inEucalyptus camaldulensis L. by fixing the stem at an angle. Proteins in the differentiating tissue of tension wood were compared to those of normal wood on sodium dodecyl sulfate polyacrylamide gel electrophoresis. An obvious difference was found in the salt-soluble fraction of 14 days after inclination. At least five bands (19,22,37,41, and 55kDa) were specific in the differentiating tissue of tension wood. These proteins were bound to the cell wall, plasma membrane, or both by their electric charge; they were undetectable until 14 days after inclination. Mature tension wood was observed in the tissue at 14 days. Thus, all differentiating tissue at 14 days was produced after inclination. On the other hand, the differentiating zone at 7 days contained the same tissue, as in tension wood estimated by the vessel number and diameter during the early phase; and the tissue was indistinguishable from normal wood during the late phase. The proteins found here were related to the phenomenon occurring in the late stage of xylem differentiation. 相似文献
462.
Hirofumi Hirai Takayuki Oniki Ryuichiro Kondo Kokki Sakai 《Journal of Wood Science》2000,46(2):164-166
Change in the oxidation state of manganese atoms in unbleached hardwood kraft pulp (UKP) during the biological bleaching of UKP withPhanerochaete sordida YK-624 was determined by the electron spin resonance (ESR) method. The spectrum of Mn(II), which reveals hyperfine splitting, was not observed in the ESR analysis of UKP, but the spectrum for manganese dioxide was observed. After fungal treatment of UKP withP. sordida YK-624, the spectrum of Mn(II) was detected. The reduction of manganese dioxide was triggered by the increase in NADPH-dependent ferrireductase activity. It is concluded that the manganese dioxide dominant in UKP was reduced byP. sordida YK-624 to Mn(II), which stimulates the production and function of manganese peroxidase. 相似文献
463.
Haruhiko Hino Takashi Kitagawa Takayuki Matsumoto Yoshinori Aoki Shingo Kimura 《Fisheries Oceanography》2019,28(4):359-371
Vertical movements related to the thermoregulation were investigated in 12 juvenile bigeye tuna (Thunnus obesus) in Japanese waters using archival tag data. Movements changed with time of day, season, and body size. During daytime, bigeye tuna descended to greater depths, presumably to feed in the deep scattering layer (DSL). Thereafter, they repeatedly ascended to shallower layers, suggesting attempts at behavioral thermoregulation, although the beginning of vertical thermoregulatory ascents might reflect a shift in DSL depth. By the end of such movement, the whole‐body heat‐transfer coefficient might decrease because, although the depth and ambient temperature of the upper layers did not change, the body temperature gradually decreased significantly just after ascent for thermoregulation. Seasonal patterns indicated that the vertical thermal structure of the ocean might influence this ascent behavior. For example, from January to May, bigeye tuna made fewer ascents to less shallow waters, suggesting that they respond to increasing depths of the mixed surface layer by reducing energy expenditure during vertical migration. In addition, as body size increased, fewer thermoregulatory ascents were required to maintain body temperature, and fish remained deeper for longer periods. Thus, vertical thermoregulatory movements might change with body size as bigeye tuna develop better endothermic and thermoregulatory abilities. We hypothesize that bigeye might also increase cold tolerance as they grow, possibly due to ontogenetic shifts in cardiac function. 相似文献
464.
Satoshi KAMOTO Masahiro SHINADA Daiki KATO Masaya TSUBOI Sho YOSHIMOTO Ryohei YOSHITAKE Shotaro ETO Namiko IKEDA Yosuke TAKAHASHI Yuko HASHIMOTO James CHAMBERS Kazuyuki UCHIDA Shinji YAMADA Mika K. KANEKO Ryohei NISHIMURA Yukinari KATO Takayuki NAKAGAWA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(11):1795
Podoplanin is expressed in various human tumors where it promotes tumor progression, epithelial-mesenchymal transition, and distant metastasis. Podoplanin is also expressed in cancer-associated fibroblasts and induces tumor malignancy. The objective of this study was to evaluate podoplanin expression in various types of feline tumor tissues. Immunohistochemical analysis revealed that podoplanin was expressed in cells of 13/15 (87%) squamous cell carcinomas and 5/19 (26%) fibrosarcomas. Moreover, cancer-associated fibroblasts expressed podoplanin in most tumor types, including 18/21 (86%) mammary adenocarcinoma tissues. Our findings demonstrate that various types of feline tumor tissues expressed podoplanin, indicating the importance of the comparative aspects of podoplanin expression, which may be used as a novel research model for podoplanin biology. 相似文献
465.
Interspecific hybrids of Alstroemeria ligtu L. hybrid (LH) (2n = 16) and A. pelegrina L. var. rosea (PR) (2n = 16) synthesized by cross-breeding, exhibited a low pollen fertility and failed to produce normal seeds by self-pollination. To produce amphidiploids of LH × PR the ovules of LH × PR were treated with 0.05% aqueous colchicine for 2, 4 or 8 days or the rhizomes of the mature LH × PR were treated with 0.5% aqueous colchicine for 1, 2, 4 or 7 days. A total of 6 mature plants were obtained from the ovules of LH × PR treated with colchicine. Among them 2 plants derived from the ovules treated with colchicine for 4 days were found to be amphidiploids (2n = 32). A total of 17 rhizomes treated with colchicine, sprouted. Among them, 1 and 3 plants developed from the rhizomes treated with colchicine, for 1 and 4 days, respectively, were fertile. The plants developed from seeds obtained by self-pollination were amphidiploids with a chromosome number of 2n = 32. Although each of the amphidiploids induced by colchicine and LH × PR exhibited the characteristics of the parents, the colchicine-induced amphidiploids showed larger flowers than LH × PR and grew more vigorously. Even though the amphidiploids failed to produce normal seeds by self-pollination, pollen fertility was relatively high and their progenies were produced from self-pollinated ovules by ovule culture. The amphidiploids were crossed with LH, PR, A. aurea Graham, A. paupercula Philippi and A. psittacina Lehm., resulting in the production of triploids with a chromosome number of 2n = 24. 相似文献
466.
Takayuki Kobayashi Toshiya Nagase Akinori Hino Toshio Takeuchi 《Fisheries Science》2008,74(3):649-656
ABSTRACT: A continuous culture of rotifer was conducted to investigate the effect of combination feeding of both a high density of Nannochloropsis oculata (N) and condensed freshwater Chlorella (FC) on the fatty acid composition of L-type rotifer Brachionus plicatilis in a continuous culture system. The algal feeding of the rotifers was carried out in three successive steps: N-feeding → N+FC-feeding → FC-feeding. The culture was conducted at 24°C and 25–27 psu in a 2000 mL bottle with 50% of water exchanged daily. The combination N+FC-feeding was effective in increasing rotifer density. The rotifers fed on N+FC (N+FC-R) had more non-polar lipids than polar ones, similar to those on N (N-R), opposite to the rotifers fed on FC (FC-R). N+FC-R contained higher levels of 16:2, 18:2n-6 (linoleic acid [LA]) and 20:2n-6, but lower levels of 18:1, 20:4n-6 (arachidonic acid), 20:5n-3 (eicosapentaenoic acid [EPA]) and 22:5n-3 (docosapentaenoic acid [DPA]) compared with N-R. Whereas N+FC-R contained higher levels of 16:1n-7, EPA and DPA, but lower levels of 16:2 and LA compared with FC-R. N+FC-R had more DPA in polar lipids than in non-polar ones. The Σn-6/Σn-3 ratio in N+FC-R was 0.9–1.0, significantly different from those in N-R (0.4) and FC-R (6.6–8.4). Therefore, it is inferred that the fatty acid profile of the N+FC-R cultured in a continuous culture system was affected by both N and FC. Also, the combination N+FC-feeding may be effective in manipulating the Σn-6/Σn-3 ratio in continuously cultured rotifers. 相似文献
467.
Yoshiki Kato Takayuki Takebe Shukei Masuma Takashi Kitagawa Shingo Kimura 《Fisheries Science》2008,74(1):48-53
ABSTRACT: Physical conditions such as oceanic turbulence related to food availability are considered to be important factors affecting fish larval survival. Rearing experiments were conducted to elucidate the effects of turbulence on the survival and feeding rates during the initial feeding period of Pacific bluefin tuna Thunnus orientalis . Six levels of turbulence intensity were provided by changing flow rates from pipes set on the bottom of rearing tanks. The result showed a dome-shaped relationship between turbulence level and survival rate, in which the feeding rate appeared higher at a logged turbulence energy dissipation rate of −6.32, and decreased at both higher and lower turbulence levels. Compared with the turbulence intensity in the ocean, the optimal turbulence level for Pacific bluefin tuna larvae corresponded to the turbulence caused by sea surface winds with speeds of 4–12.5 m/s. The estimated optimal turbulence intensity for Pacific bluefin tuna larvae is comparable to that for yellowfin tuna Thunnus albacares . 相似文献