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1.
A new snake-eel,Apterichtus keramanus, is described on the basis of a single 276-mm TL specimen trawled from the coast of Kerama Islands, Okinawa Prefecture, Japan. The species is unique in the genus in having the posterior nostril opening entirely inside the mouth and a dark band running from the anteroventral margin of the eye to the upper lip.  相似文献   
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A factor responsible for stimulating an increase in ornithine decarboxylase activity in the liver of mice was found in tumor cell-free ascites fluid of mice 3 days after inoculation of tumor cells. The factor was purified about 70-fold in 25% yield from tumor cell-free ascites fluid. As little as 1 μg of protein of purified fraction, injected intraperitoneally into normal mice, significantly increased the activity of ornithine decarboxylase in the liver. The most active preparation of the factor formed two major protein bands on analytical polyacrylamide gel electrophoresis and both these bands stained with periodic acid-Schiff's reagent. The factor was a heat-labile, alkaline-stable, acidic protein with a molecular weight of more than 300 000. It was inactivated by treatment with 10 mM dithiothreitol, 5M urea, pronase or mixed glycosidase, but was stable on treatment with DNAase, RNAase or neuraminidase.  相似文献   
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When neutrophils were stimulated by the chemotactic peptide, fMLP, a rapid, transient increase in the activity of diacylglycerol(DG) kinase in the membrane fraction was detected. DG kinase in cytosol, on the contrary, showed a transient decrease. The total activity in homogenates was not affected. Tetradecanoylphorbol acetate(TPA) and 1-oleoyl-2-acetylglycerol(OAG) also caused an increase in DG kinase activity in the membrane fraction. Km value of DG kinase in membranes was not changed by the treatment of fMLP or TPA, though Vmax was increased. Considering these results, DG kinase may translocate from cytosol to membranes on stimulation by fMLP, TPA or OAG in neutrophils. The translocation may play important roles in regulation of protein kinase C activity, since DG kinase competes with protein kinase C for DG, which is formed by receptor-activation.  相似文献   
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A Namalwa cell line, KJM-1, which was adapted to serum-free medium is thought to be a good host cell line for recombinant DNA technology. We previously reported the expression of human -interferon (-IFN) in Namalwa KJM-1 (Miyaji, 1989a). The utility of Namalwa KJM-1 for expression of foreign genes was further examined. As a target gene to be expressed, human lymphotoxin (hLT) cDNA was used. It was engineered for expression in Namalwa KJM-1 using a simian virus 40 (SV40)-based expression vector pAGE107 (Miyaji, 1989a). It contains all components necessary for the expression of cDNA in mammalian cells. The expression vector was introduced into Namalwa KJM-1 by electroporation. Among the transformants, clone 7 was further examined for the expression of hLT in serum-free medium. The production level of hLT was augmented with the increase of the cell density. Thus it was further indicated that Namalwa KJM-1 is useful for production of foreign gene products.Abbreviation HEPES 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid  相似文献   
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Soil specimens obtained from several areas of Japan, which are closely located to or facing the Continental land of China, were examined for the distribution of Clostridium botulinum, especially pertaining to types A and B. A total of 266 specimens of Japan, when cultured, showed no type A or B toxicity, although 30 (11.3%), 4 (1.5%), and 10 (3.8%) of the specimens showed C1, C2, and type E toxicities, respectively. On the contrary, types A and/or B toxicities were shown, by the same method, in 14 of 20 specimens of Shinkiang district, China. The highest number of C. botulinum cells found in one gram of soil specimen was 25 for type A and 10 for type B.  相似文献   
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An attempt was made to detect the fluorescent bodies (F-body), using Quinacrine mustard (Q-M) staining in the spermatozoa from eight mammalian species (human, bull, boar, dog, rabbit, rat, mouse, and mastomys) as well as in the cock (used as negative control). Sperm suspension, prepared after rinsing by repeated centrifugation with phosphate buffered saline (PBS), was either stained with Q-M for 24 h or treated with protease and then stained with Q-M for 60 min. The final concentration of Q-M in the mixed staining sperm suspension was 0.025 mg/ml. The examination using a reflecting fluorescent microscope revealed that the F-body found in human sperm was also present in the sperm of all the mammals but not in the cock after 24 h of staining. The enzyme-treated specimens showed higher incidences of F-bodies than specimens stained for 24 h without enzymatic digestion. These findings strongly suggest that the F-body is commonly present in the spermatozoa of many mammalian species.  相似文献   
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The polymorphic variation of liver GM1 (NeuGc) ganglioside was found in inbred strains of the mouse. The genetic analysis using C57BL/10 (GM1-negative) and SWR (GM1-positive) mice revealed that a single autosomal gene (Ggm-1) was involved in the expression of liver GM1(NeuGc) and that C57BL/10 mice lacking GM1(NeuGc) expression carried a defective gene on Ggm-1. Since our previous study on H-2 congenic mice indicated that Ggm-1 was linked to the H-2 complex, in this study we measured recombination frequencies among Ggm-1, Go-1 and H-2K in the backcross progeny between (C57BL/10 × SWR)F1 and C57BL/10. Ggm-1 was mapped 1 cM centromeric to H-2K on chromosome 17.Abbreviations used in this paper GM1(NeuGc) Gal1-3GalNAc1-4 (NeuGc2-3)Gal1-4Glc1-ceramide - GM2(NeuGc) Gal1-4(Neu Gc2-3)Gal1-4Glc1-ceramide - GM3(NeuGc) NeuGc2-3Gal1-4 Glc1-ceramide - GD1a(NeuGc) NeuGc2-3Gal1-3GalNAc1-4 (NeuGc2-3)Gal1-4Glc1-ceramide  相似文献   
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