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101.
Yamaguchi H Zhu J Yu T Sasaki K Umetsu H Kidachi Y Ryoyama K 《Cell biology international》2007,31(6):638-644
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Al-Mamun M Yamaki K Masumizu T Nakai Y Saito K Sano H Tamura Y 《International journal of biological sciences》2007,3(6):349-355
Free radicals are not only destructive to the living cells but also reduce the quality of animal products through oxidation. As a result the superoxide anion radical (O2-), one of the most destructive reactive oxygen species, is a matter of concern for the animal scientists as well as feed manufacturers to ensure the quality of product to reach consumers demand. The superoxide anion radical scavenging activities (SOSA) of water and MeOH extracts of 2 herbs and 9 pasture samples collected from lowland and highland swards were determined against a 5,5-dimethyl-1-pyroline-N-oxide-O2-spin adduct based on a hypoxanthine-xanthine oxidase reaction using electron spin resonance spectrometry. Both the water and MeOH extracted SOSA differed among the herbs and pastures. Species and altitudinal variations were observed between extraction methods. The herbs were higher in both water and MeOH extracted SOSA than the pastures except for water extracts of one pasture, white clover (Trifolium repens L.). Among the pastures, quackgrass (Agrophyron repens L.) showed higher SOSA in both the MeOH and water extracts, and timothy (Phleum pretense L.) showed higher MeOH extracted SOSA. It is apparent that the kind and amount of antioxidants differ among herbs and pastures. Animal health and quality of animal products could be improved by adequate selection and combining of herbs and pastures having higher SOSA. 相似文献
104.
We have developed a procedure to process echosounding data to map the distribution of submerged aquatic macrophytes in the
southern basin of Lake Biwa, a water body that has a surface area of 52 km2 and a mean depth of 4 m. Echosounding observations were made along 27 transect lines spaced at 500-m intervals on August
4 and September 2 and 30, 2003. Quantitative vegetation data including percent coverage, mean vegetation height, and percent
vegetation infestation were directly determined using image data from the echosounder recorded digitally on videotape. Based
on the image data from an echosounder, a regression model was developed for estimating biomass of submerged macrophytes. The
regression model using the total echo strength as the explanatory variable could reliably estimate macrophyte biomass up to
300 g m−2. Distribution maps of macrophyte height and biomass suggest that the recent summer decline of submerged macrophytes started
earlier in shallow areas (<3 m of depth) than deep areas (>4 m) in the southern basin of Lake Biwa. 相似文献
105.
Moriyama A Kii I Sunabori T Kurihara S Takayama I Shimazaki M Tanabe H Oginuma M Fukayama M Matsuzaki Y Saga Y Kudo A 《Genesis (New York, N.Y. : 2000)》2007,45(2):90-100
In the past decades, the function of the Wnt canonical pathway during embryogenesis has been intensively investigated; however, little survey of neonatal and adult tissues has been made, and the role of this pathway remains largely unknown. To investigate its role in mature tissues, we generated two new reporter transgenic mouse lines, ins-TOPEGFP and ins-TOPGAL, that drive EGFP and beta-galactosidase expression under TCF/beta-catenin, respectively. To obtain the accurate expression pattern, we flanked these transgenes with the HS4 insulator to reduce chromosomal positional effects. Analysis of embryos showed that the reporter genes were activated in regions where canonical Wnt activity has been implicated. Furthermore, their expression patterns were consistent in both lines, indicating the accuracy of the reporter signal. In the neonatal brain, the reporter signal was detected in the mesencephalon and hippocampus. In the adult mice, the reporter signal was found in the mature pericenteral hepatocytes in the normal liver. Furthermore, during inflammation the number of T cells expressing the reporter gene increased in the adult spleen. Thus, in this research, we identified two organs, i.e., the liver and spleen, as novel organs in which the Wnt canonical signal is in motion in the adult. These transgenic lines will provide us broader opportunities to investigate the function of the Wnt canonical pathway in vivo. 相似文献
106.
Hydrobiologia - During larval development of the intertidal barnacle Fistulobalanus albicostatus, larvae in the naupliar stages I and II (NI&II) possess a single naupliar eye, and later... 相似文献
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Yumi Ueki Michael A Hadders Melanie B Weisser Isha Nasa Paula SoteloParrilla Lauren E Cressey Tanmay Gupta Emil P T Hertz Thomas Kruse Guillermo Montoya A Arockia Jeyaprakash Arminja Kettenbach Susanne M A Lens Jakob Nilsson 《EMBO reports》2021,22(7)
The shugoshin proteins are universal protectors of centromeric cohesin during mitosis and meiosis. The binding of human hSgo1 to the PP2A‐B56 phosphatase through a coiled‐coil (CC) region mediates cohesion protection during mitosis. Here we undertook a structure function analysis of the PP2A‐B56‐hSgo1 complex, revealing unanticipated aspects of complex formation and function. We establish that a highly conserved pocket on the B56 regulatory subunit is required for hSgo1 binding and cohesion protection during mitosis in human somatic cells. Consistent with this, we show that hSgo1 blocks the binding of PP2A‐B56 substrates containing a canonical B56 binding motif. We find that PP2A‐B56 bound to hSgo1 dephosphorylates Cdk1 sites on hSgo1 itself to modulate cohesin interactions. Collectively our work provides important insight into cohesion protection during mitosis. 相似文献
110.
Suzuki N Shiota T Watanabe F Haga N Murashi T Ohara T Matsuo K Oomori N Yari H Dohi K Inoue M Iguchi M Sentou J Wada T 《Bioorganic & medicinal chemistry letters》2011,21(6):1601-1606
A structure-activity relationship study of 4-anilinopyrimidines for dual EGFR/Her-2 inhibitor has resulted in the identification of 4-anilino-5-alkenyl or 5-alkynyl-6-methylpyrimidine derivatives that have exhibited effective inhibitory activity against both enzymes. The presence of 5-alkenyl or 5-alkynyl moiety bearing terminal hydrophilic group played important role for inhibition of these enzymes. Selected compounds in the series demonstrated some activity against Her-2 dependent cell line (BT474). 相似文献