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91.
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Rat pancreatic juice (RPJ) reduced the mean uptake of 57CoB12 bound to rat intrinsic factor (IF) by perfused rat intestinal segments from 30.1 +/- 2.4 (pg 57CoB12 per cm intestine +/- S.E.M.) to 26.7 +/- 2.4 (p less than 0.05). RPJ activated with enterokinase reduced the uptake from 22.8 +/- 2.8 to 16.1 +/- 1.9 (p less than 0.05). RPJ also reduced the uptake from 15.8 +/- 2.3 to 8.3 +/- 2.0 (p less than 0.01) in segments from partially pancreatectomized rats. Rat bile abolished the inhibitory effect of RPJ. The results indicate that in the absence of bile the exocrine pancreatic secretion is capable of inhibiting the intestinal uptake of vitamin B12. 相似文献
93.
Self—sensitized and Rose Bengal—sensitized photo—oxidation of 4, 4′-bisacetamidostilbene (BAAS) in solution gives p—acetamidobenzaldehyde and p—acetamidobenzoic acid via the reaction of singlet oxygen with the trans isomer (la). The rate of the photo—oxidation is retarded in the presence of effective singlet oxygen quenchers. On the other hand, cls—BAAS (lb) is more stable to visible light under the conditions of Rose Bengal—sensitized photo—oxidation than trans—stilbene. 相似文献
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Extraction of a plasma time-activity curve from dynamic brain PET images based on independent component analysis 总被引:1,自引:0,他引:1
Naganawa M Kimura Y Ishii K Oda K Ishiwata K Matani A 《IEEE transactions on bio-medical engineering》2005,52(2):201-210
A compartment model has been used for kinetic analysis of dynamic positron emission tomography (PET) data [e.g., 2-deoxy-2-18F-fluoro-D-glucose (FDG)]. The input function of the model [the plasma time-activity curve (pTAC)] was obtained by serial arterial blood sampling. It is of clinical interest to develop a method for PET studies that estimates the pTAC without needing serial arterial blood sampling. For this purpose, we propose a new method to extract the pTAC from the dynamic brain PET images using a modified independent component analysis [extraction of the pTAC using independent component analysis (EPICA). Source codes of EPICA are freely available at http://www5f.biglobe.ne.jp/?kimura/Software/top.html]. EPICA performs the appropriate preprocessing and independent component analysis (ICA) using an objective function that takes the various properties of the pTAC into account. After validation of EPICA by computer simulation, EPICA was applied to human brain FDG-PET studies. The results imply that the EPICA-estimated pTAC was similar to the actual measured pTAC, and that the estimated blood volume image was highly correlated with the blood volume image measured using 15O-CO inhalation. These results demonstrated that EPICA is useful for extracting the pTAC from dynamic PET images without the necessity of serial arterial blood sampling. 相似文献
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Kenji Ozeki Yoshihiro TakagiShinobu Oda Shinichi Ohashi 《Journal of Bioscience and Bioengineering》2010,109(3):224-226
Xylanase production by a XynF1 (33 kDa)-transformant of Aspergillus oryzae RIB40 was compared between submerged cultivation (SmC) and liquid-surface immobilization (LSI) systems. While the accumulation of xylanase in the SmC decreased by prolonged incubation, LSI system enabled the continuation of xylanase production to afford 4.5-fold xylanase production compared with the SmC system. 相似文献
100.
Zedong Jiang Takasi Okimura Takeshi Yokose Yasuhiro Yamasaki Kenichi Yamaguchi Tatsuya Oda 《Journal of Bioscience and Bioengineering》2010,110(1):113-117
The effects of fucose-containing sulfated polysaccharides, ascophyllan and fucoidan, isolated from the brown alga Ascophyllum nodosum, on the growth of various cell lines (MDCK, Vero, PtK1, CHO, HeLa, and XC) were investigated. In a colony formation assay, ascophyllan and fucoidan showed potent cytotoxic effects on Vero and XC cells, while other cell lines were relatively resistant to these polysaccharides. Almost no significant effects of these polysaccharides were observed in the cell lines tested using the Alamar blue cytotoxicity assay over 48 h with varying initial cell densities (2500–20,000 cells/well) in growth medium. Interestingly, a significant growth promoting effect of ascophyllan on MDCK cells was observed, whereas treatment with fucoidan showed growth suppressive effects on this cell line under the same experimental conditions. These results suggest that ascophyllan is distinguishable from fucoidan in terms of their bioactivities. This is the first report of the growth promoting effects of a sulfated fucan on a mammalian cell line under normal growth conditions. 相似文献