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991.
An infusible emulsion of 10% eicosapentaenoic acid ethyl ester (EPA-EE, 99.2% pure) was prepared. Three ml of the emulsion was infused into tail veins of 20 Wistar rats weighing approx. 300 g. They were killed 1 h, 6 h, 24 h, 3 d and 7 d after the infusion, and fatty acid composition of various organs and plasma was analyzed along with that of control rats. There was no lipidosis in any organs of any rats. It was estimated that not less than 98% of infused EPA was cleared from plasma during the first hour after the infusion. EPA concentrations reached their peaks within 6 h after EPA infusion in plasma lipid fractions and in the phospholipid fraction of liver, heart, lung, kidney and spleen. The fatty acid composition of the phospholipid fraction of heart was very stable, and was not altered by EPA infusion except for a very slight increase in EPA at 1 h after the infusion (0.18% at 0 h to 0.56%). However, EPA concentrations increased markedly in the free fatty acid fraction of heart at 1 h after the infusion (0.15% at 0 h to 4.23%). Arachidonic acid concentrations decreased significantly within 24 h in the phospholipid fraction of organs except for heart. EPA emulsion might be useful for patients in whom a rapid increment in EPA in tissues is beneficial. 相似文献
992.
Keiko Mitsunaga-Nakatsubo Miyuki Kanda Ken Yamazaki Hiroto Kawashita Akiko Fujiwara Kazumi Yamada Koji Akasaka Hiraku Shimada Ikuo Yasumasu 《Development, growth & differentiation》1992,34(6):677-684
A marked increase in the Na+ , K+ -ATPase activity of sea urchin embryos occurred following an elevation of its mRNA level, revealed by Northern blotting analysis, in developmental period between the swimming blastula and the late gastrula stage. cDNA clone of Na+ , K+ -ATPase α-subunit, obtained from γgt10 cDNA library of sea urchin gastrulae, was digested with EcoRl ad Hindlll. The obtained 268 bp cDNA fragment, hybridized to a 4.6 Kb RNA, was used as probe for Northern blotting analysis. The level of Na+ , K+ -ATPase mRNA was higher in embryo-wall cell fraction isolated from late gastrulae (ectoderm cells) than the level in the bag fraction, containing mesenchyme cells (mesoderm cells) and archenteron (endoderm cells). The activity of Na+ , K+ -ATPase and the level of its mRNA were higher in animalized embryos obtained by pulse treatment with A23187 for 3 hr, starting at the 8–16 cell stage and were considerably lower in vegetalized embryos induced by 3 hr treatment with Li+ than that in normal embryos at the post gastrula corresponidng stage. Augmentation of Na+ , K+ -ATPase gene expression can be regarded as a marker for ectoderm cell differentiation at the post gastrula stage, which results from determination of cell fate in prehatching period. 相似文献
993.
Yusen Liu Satoru Ishii Masaya Tokai Hiroko Tsutsumi Osamu Ohki Rinji Akada Kazuma Tanaka Eiko Tsuchiya Sakuzo Fukui Tokichi Miyakawa 《Molecular & general genetics : MGG》1991,227(1):52-59
Summary
Saccharomyces cerevisiae genomic clones that encode calmodulin-binding proteins were isolated by screening a λgt11 expression library using125I-labeled calmodulin as probe. Among the cloned yeast genes, we found two closely related genes (CMP1 andCMP2) that encode proteins homologous to the catalytic subunit of phosphoprotein phosphatase. The presumed CMP1 protein (62999
Da) and CMP2 protein (68496 Da) contain a 23 amino acid sequence very similar to those identified as calmodulin-binding sites
in many calmodulin-regulated proteins. The yeast genes encode proteins especially homologous to the catalytic subunit of mammalian
phosphoprotein phosphatase type 213 (calcineurin). The products of theCMP1 andCMP2 genes were identified by immunoblot analysis of cell extracts as proteins of 62000 and 64000 Da, respectively. Gene disruption
experiments demonstrated that elimination of either or both of these genes had no effect on cell viability, indicating that
these genes are not essential for normal cell growth. 相似文献
994.
Summary We found a specific eye morphology designated as Square, which is induced when some Drosophila melanogaster strains harboring P elements are crossed with the 2–3 strain carrying a modified P element, P[ry
+, 2–3], which produces transposase in somatic tissue. This phenotype was dominant and also induced in the reciprocal crosses. Square was induced when the 2–3 strain was crossed with Q and M strains such as the snw (M) strain carrying three small P elements but not with P strains. Inheritance of Square was also tested and its phenotype was not transmitted to the next generation. These results suggest that Square is caused by the transposition of P elements in somatic cells. 相似文献
995.
996.
997.
Summary Hydrophobic cotton cloths were prepared by heating cotton flannel in a mixture of alcohols or phenols, epichlorohydrin and 4 M NaOH. These cloths adsorbed as much bovine serum albumin as did a commercial preparation of phenyl agarose. -Galactosidase and -glucosidase adsorbed on the cloths were about 50% as active as free enzymes. Glucoamylase immobilized on naphthyl cloth in a packed bed column efficiently hydrolyzed soluble starch to glucose. These inexpensive media would be useful for commercial-scale hydrophobic chromatography and enzyme immobilization. 相似文献
998.
H Suzuki T Naitoh S Kuniyoshi N Banba H Kuroda Y Suzuki M Hiraiwa N Yamazaki M Ishikawa Y Hashigami 《Endocrinologia japonica》1984,31(6):755-761
To investigate the relationship between serum levels of Coenzyme Q10 and cardiac performance in thyroid disorders, we studied the cardiac performance and assessed serum levels of thyroid hormones and Coenzyme Q10 in 20 patients with hyperthyroidism, 5 patients with hypothyroidism and 10 normal subjects. A significant inverse correlation between thyroid hormones and Coenzyme Q10 levels was found by performing partial correlation analysis. Because low serum levels of Coenzyme Q10 were found in thyrotoxic patients and congestive heart failure may occur as a result of severe hyperthyroidism, 120 mg of Coenzyme Q10 was administered daily for one week to 12 hyperthyroid patients and the change in cardiac performance was assessed. Further augmentation of cardiac performance was found in hyperthyroid hearts, which were already augmented, after the administration of Coenzyme Q10. It appears, therefore, that the Coenzyme Q10 dose actually has a therapeutic value for congestive heart failure induced by severe thyrotoxicosis. 相似文献
999.
To test the validity of previous results the inducibility of amylase as well as other biochemical parameters was measured using 45 homozygous strains of Drosophila melanogaster from Akayu, Japan. Only the inducibility (but not protein contents or specific activity of the enzyme) was highly correlated with productivity measured using a starch food regime (rp = 0.41, P < 0.005, rg = 0.73 ± 0.21). Inducibility was also negatively correlated with developmental time using starch food; namely, the one with high inducibility developed the fastest. Population cage experiments using 1600 genomes from the same natural population showed that the inducibility responded positively to natural selection (1.6-fold increase in inducibility in cages using starch food relative to those using normal food), but little frequency change of allozymes was observed. All of these results were consistent and indicated that polymorphisms of inducing factors or regulatory genes were major determinants of fitness differences in a particular environment and may be the genetic materials responsible for the adaptive evolution of organisms, at least in amylase loci. 相似文献
1000.
Measurement of Fitness and Its Components in Six Laboratory Strains of DROSOPHILA MELANOGASTER 总被引:2,自引:2,他引:0
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Yamazaki T 《Genetics》1984,108(1):201-211
Six laboratory strains of Drosophila melanogaster were used to measure "net fitness" and its components by interspecific competition with D. hydei using 100 experimental populations. The "total competitive ability," an estimate of net fitness measured in these competition experiments, was tightly correlated with another measure of net fitness, the population size, in single-species experiments (phenotypic correlation rp = 0.675 and genotypic correlation rg = 0.997). Other components of fitness were also measured simultaneously, and the correlation with the net fitness was calculated. The very high correlation between two measurements of net fitness and lower correlations between net fitness and components of fitness suggests that these net fitness measures are more reliable estimates of the "real net fitness" than the components of fitness. 相似文献