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331.
Kazufumi OSAKO Akira YAMAGUCHI Takao KUROKAWA Koichi KUWAHARA Hiroaki SAITO Yukinori NOZAKI 《Fisheries Science》2002,68(3):587-594
ABSTRACT: The chemical components and body color of horse mackerel caught between July 1997 and May 2000 were studied. The fish were caught with small- to medium-sized purse seine offshore from Nagasaki and from Tsushima, and with bull trawl seine and medium- to large-sized purse seine in the East China Sea. The crude lipid content of the fish caught offshore from Tsushima was higher than that of the others, and there were no significant differences among the other catches. The extractive nitrogen content of the fish caught with bull trawl seine was somewhat lower than that of the others. The body colors of the fish differed from those suggested by their common names: Kuroaji (black) , Kiaji (yellow), and Shiroaji (white). The crude lipid content and body color indicated that there was no difference in quality among the catches, with the exception of the crude lipid content of the Tsushima catch. 相似文献
332.
Cryopreservation is becoming a very important tool for the long-term storage of plant genetic resources and efficient cryopreservation protocols have been developed for a large number of plant species. Practical procedures, developed using in vitro tissue culture, can be a simple and reliable preservation option of potato genetic resources rather than maintaining by vegetative propagation in genebanks due their allogamous nature. Cryopreserved materials insure a long-term backup of field collections against loss of plant germplasm. Occurrence of genetic variation, in tissue culture cells during prolonged subcultures, can be avoided with suitable cryopreservation protocols that provide high regrowth, leading and facilitating a systematic and strategic cryo-banking of plant genetic resources. Cryopreservation protocols for potato reviewed here, can efficiently complement field and in vitro conservation, providing for preservation of genotypes difficult to preserve by other methods, wild types and other species decided as priority collections. 相似文献
333.
K Mukai A Ouchi S Takahashi K Aizawa T Inakuma J Terao S Nagaoka 《Journal of agricultural and food chemistry》2012,60(32):7905-7916
Measurements of the singlet oxygen ((1)O(2)) quenching rates (k(Q) (S)) and the relative singlet oxygen absortpion capacity (SOAC) values were performed for 16 phenolic antioxidants (tocopherol derivatives, ubiquinol-10, caffeic acids, and catechins) and vitamin C in ethanol/chloroform/D(2)O (50:50:1, v/v/v) solution at 35 °C. It has been clarified that the SOAC method is useful to evaluate the (1)O(2)-quenching activity of lipophilic and hydrophilic antioxidants having 5 orders of magnitude different rate constants from 1.38 × 10(10) M(-1) s(-1) for lycopene to 2.71 × 10(5) for ferulic acid. The logarithms of the k(Q) (S) and the SOAC values for phenolic antioxidants were found to correlate well with their peak oxidation potentials (E(p)); the antioxidants that have smaller E(p) values show higher reactivities. In previous works, measurements of the k(Q) (S) values for many phenolic antioxidants were performed in ethanol. Consequently, measurements of the k(Q) (S) and relative SOAC values were performed for eight carotenoids in ethanol to investigate the effect of solvent on the (1)O(2)-quenching rate. The k(Q) (S) values for phenolic antioxidants and carotenoids in ethanol were found to correlate linearly with the k(Q) (S) values in ethanol/chloroform/D(2)O solution with a gradient of 1.79, except for two catechins. As the relative rate constants (k(Q)(AO) (S)/k(Q)(α-Toc) (S)) of antioxidants (AO) are equal to the relative SOAC values, the SOAC values do not depend on the kinds of solvent used, if α-tocopherol is used as a standard compound. In fact, the SOAC values obtained for carotenoids in mixed solvent agreed well with the corresponding ones in ethanol. 相似文献
334.
Sheng-An Tang Qianxiang Zhou Wen-Zhi Guo Yuling Qiu Ran Wang Meihua Jin Wenjing Zhang Ke Li Takao Yamori Shingo Dan Dexin Kong 《Marine drugs》2014,12(7):4200-4213
Stellettin B was isolated from marine sponge Jaspis stellifera. In vitro antitumor activities were investigated on 39 human cancer cell lines. Stellettin B exhibited highly potent inhibition against the growth of a human glioblastoma cell line SF295, with a GI50 of 0.01 μM. In contrast, stellettin B showed very weak inhibitory activity on normal cell lines including HMEC, RPTEC, NHBE and PrEC, with GI50s higher than 10 μM, suggesting its relatively selective cytotoxicity against human cancer cells compared to normal human cell lines. We then focused on the antitumor activity of this compound on SF295 cells. Flow cytometric analysis indicated that stellettin B induced apoptosis in SF295 cells in a concentration-dependent manner. Further study indicated that stellettin B increased the production of ROS, the activity of caspase 3/7, as well as the cleavage of PARP, each of which is known to be involved in apoptosis. To investigate the molecular mechanism for cell proliferation inhibition and apoptosis induction, effect on the phosphorylation of several signal proteins of PI3K/Akt and RAS/MAPK pathways was examined. Stellettin B inhibited the phosphorylation of Akt potently, with no activity on p-ERK and p-p38, suggesting that inhibition of PI3K/Akt pathway might be involved in the antiproliferative and apoptosis-inducing effect. However, homogenous time-resolved fluorescence (HTRF) assay indicated that stellettin B did not inhibit PI3K activity, suggesting that the direct target might be signal protein upstream of Akt pathway other than PI3K. 相似文献
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336.
Yoshio Awaya Nobuhiko Tanaka Kunihiro Tanaka Gen Takao Eiji Kodani Satoshi Tsuyuki 《Journal of Forest Research》2000,5(4):247-258
The relationship between the stand parameters (top layer height (H1) and volume/ha (Vha)) and digital number (DN) were evaluated
for evergreen conifer stands using three airborne images with 4-m spatial resolution, which were taken in June 1995, September
1993, and October 1994 using the Compact Airborne Spectrographic Imager (CASI). Estimation accuracy of the stand parameters,
their seasonal changes, and suitable wavelength were analyzed using correlation coefficients and a regression analysis. The
minimum DN of stands, which showed the darkness of a canopy shadow, had a higher correlation with H1 than the average and
maximum DN while the average DN had a higher correlation with Vha. The green channels gave the highest correlation coefficients
with H1 and Vha, which exceeded — 0.9 for the September and October images. However, the red channels had a consistently high
correlation with the stand parameters for the three images. The near infrared channels gave poor correlations with H1 and
Vha for the June image. Spectral variations among trees may affect the relationship between DN and the stand parameters in
the leaf maturation period in June. Consequently, the late growing season was better at giving consistent results for the
stand parameter studies. There was a linear relationship between the measured and the estimated stand parameters for the validation
plots especially for the H1 case of September with sufficient accuracy. Nadir viewing images, which had high spatial resolution
and a wide dynamic range such as the CASI images, were necessary to estimate the stand parameters accurately.
This study was also partly supported by the research project, ‘A Study of Accurate Biomass Estimation using Airborne Imagery,’
of the Science and Technology Agency of Japan. Comments from the editors helped improve the contents of the paper. 相似文献
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