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411.
Thirteen essential oils were examined for their antioxidant activity using three different assay systems. Jasmine, parsley seed, rose, and ylang-ylang oils inhibited hexanal oxidation by over 95% after 40 days at a level of 500 microg/mL in the aldehyde/carboxylic acid assay. Scavenging abilities of the oils for the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical ranged from 39% for angelica seed oil to 90% for jasmine oil at a level of 200 microg/mL. The greatest inhibitory activity toward malonaldehyde (MA) formation from squalene upon UV-irradiation was obtained from parsley seed oil (inhibitory effect, 67%), followed by rose oil (46%), and celery seed oil (23%) at the level of 500 microg/mL. The main compounds of oils showing high antioxidant activity were limonene (composition, 74.6%) in celery seed, benzyl acetate (22.9%) in jasmine, alpha-pinene (33.7%) in juniper berry, myristicin (44%) in parsley seed, patchouli alcohol (28.8%) in patchouli, citronellol (34.2%) in rose, and germacrene (19.1%) in ylang-ylang.  相似文献   
412.
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   
413.
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   
414.
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   
415.
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   
416.
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   
417.
Adult red swamp crayfish ( Procambarus clarkii ) were held in fecal collection chambers and fed common feedstuffs isosubstituted in experimental diets. Apparent dry matter digestibility (ADMD) and apparent crude protein digestibility (ACPD) coefficients were determined by the total collection and indicator (chromic oxide) methods. Feedstuffs tested were menhaden fish meal, soybean meal, alpha-soy protein, casein, gelatin, wheat bran, rice bran, wheat gluten, shrimp meal, crab chitin, cellulose, squid meal, corn starch and diatomaceous sand. Rate of consumption of plant feedstuffs was generally higher than feedstuffs of animal origin. Consumption of fish meal and shrimp meal was low (0.59 and 0.44% body weightlday, respectively). Fecal chromium concentrations were lower than chromium concentrations of experimental diets and precluded calculation of realistic coefficients by the indicator method. Analysis of refused feed samples indicated that crayfish did not consume the indicator in the same proportion as the remainder of the diet; therefore, the total collection method was judged the better approach to determining digestion coefficients. ADMD and ACPD coefficients of plant feedstuffs were generally higher than coefficients determined for animal feedstuffs. ADMD coefficients indicated substantial carbohydrate digestion by crayfish.  相似文献   
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420.
The phylogenetic relationships among Erwinia amylovora biovar 4 (the pathogen of bacterial shoot blight of pear in Japan), other biovars of E. amylovora, and Erwinia pyrifoliae were investigated using the sequences of 16S rRNA, gyrB, and rpoD genes. The tested isolates formed two distinct monophyletic groups in the phylogenetic trees constructed based on the gyrB gene, rpoD gene, or a combination of the three genes: group 1 contained E. amylovora biovars 1, 2, and 3; group 2 contained E. amylovora bv. 4 and E. pyrifoliae. This phylogenetic analysis showed that E. amylovora bv. 4 was more closely related to E. pyrifoliae than to other biovars of E. amylovora. The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under the accession numbers AB242876 to AB242925.  相似文献   
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