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1.
Y Ishikawa K Kobayashi K Seki H Mizutani Y Kawasaki J Koike K Ijiri M Yamashita K Sugiura J Poynter T MacCallum G Anderson 《Biological Sciences in Space》1998,12(4):366-372
Several soluble components, peptidase and amino acids, and carbon isotopic ratio in the water retrieved from flight experiments of Autonomous Biological Systems (ABS) as well as ground control samples are analyzed to interpret the condition, dynamics, material balance of the ABS ecosystems. Organic carbons in flight samples were found to be more abundant compared with the control ones, which suggested the uniform ecosystems in low gravity might easily dissolve more soluble components. The Mir-1997 flight sample showed higher C/N ratio probably because of the dissolution of carbon-rich plant materials. 相似文献
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Circulating tumor cells (CTCs), shed from primary tumors and disseminated into peripheral blood, are playing a major role in metastasis. Even after isolation of CTCs from blood, the target cells are mixed with a population of other cell types. Here, we propose a new method for analyses of cell mixture at the single-cell level using a microfluidic device that contains arrayed electroactive microwells. Dielectrophoretic (DEP) force, induced by the electrodes patterned on the bottom surface of the microwells, allows efficient trapping and stable positioning of single cells for high-throughput biochemical analyses. We demonstrated that various on-chip analyses including immunostaining, viability/apoptosis assay and fluorescent in situ hybridization (FISH) at the single-cell level could be conducted just by applying specific reagents for each assay. Our simple method should greatly help discrimination and analysis of rare cancer cells among a population of blood cells. 相似文献
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Summary An activated carbon column was utilized for the synthesis of disaccharides by use of a reversed hydrolysis activity of an immobilized -galactosidase column in order to shift the equilibrium to the direction of condensation. The yields of lactulose and allo-lactulose from galactose and fructose, and N-acetyl lactosamine and N-acetyl allolactosamine from galactose and N-acetyl glucosamine, were 11.3% and 10.0%, respectively. 相似文献
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Abstract Biovar A strains of Fusobacterium necrophorum exhibited high hydrophobicity when examined by the method of Rosenberg et al. Biovar B strains showed a lower cell surface hydrophobicity than biovar A strains. Biovar B strains were divided into 2 groups according to their hydrophobic activity. The strains of biovar A and the first group of biovar B were increasingly removed from aqueous phase to octane phase by increasing the volume of octane, but the turbidity of the second group of biovar B was not significantly affected. The hydrophobicity of biovar A strains decreased on heating at 60 and 100°C for 30 min. 相似文献
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A killer strain was discovered in cellular slime molds. The wild isolate CK-8 of Polysphondylium pallidum kills all other strains in Polysphondylium and Dictyostelium, as far as could be determined, except strain CK-8 itself and its complementary mating type strain CK-9. Growth-phase cells of CK-8 excrete a killer factor which is sensitive to heat, above 60°C for 5 min, and trypsin. The apparent molecular mass of the factor was determined at 10 000–12 000.Abbreviations BSS
Bonner's salt solution
- CM
conditioned medium 相似文献
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Atsushi Uchida Takuya Fujimoto Youich Mizutani 《Cancer immunology, immunotherapy : CII》1990,31(1):60-64
Summary During interaction with autologous tumor cells large granular lymphocytes (LGL) of cancer patients released a soluble cytotoxic factor, termed LGL-derived cytotoxic factor, which mediated lysing of autologous fresh tumor cells. The cytotoxic factor was compared with purified human recombinant cytotoxic cytokines, including tumor necrosis factor (TNF), lymphotoxin (LT), interferon (IFN) , IFN, interleukin-1 (IL-1) and IL-2. The LGL cytotoxic factor exhibited cytotoxicity against autologous and allogeneic fresh human tumor cells in an 18-h51Cr-release assay, while these target cells were resistant to lysing by any of the recombinant cytokines. Mixtures of recombinant(r) TNF, rLT, rIFN, rIFN, rIL-1 and rIL-2 were still unable to produce cytotoxic effects on fresh human tumor cells. Treatment with monoclonal and polyclonal antibodies directed against rTNF, rLT, rIFN, rIFN, or rIL-1 did not inhibit the cytotoxic activity of LGL-derived cytotoxic factor against fresh human tumor cells. Even a mixture of all the antibodies was incapable of blocking the cytolytic activity of the factor to fresh human tumor cells. Furthermore, intact LGL-mediated lysing of autologous tumor cells was not inhibited by any of the antibodies. These results may indicate that a cytotoxic factor produced by LGL in response to autologous tumor cells mediates lysing of fresh human tumor cells independently of TNF, LT, IFN, IL-1 and IL-2. 相似文献
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Oka Kotaro; Ikeshima Hiroko; Ishikawa Hideo; Ohta Eiji; Sakata Makoto 《Plant & cell physiology》1988,29(5):771-775
We showed that the surface charge density of protoplasts canbe estimated by the 9-aminoacridine method. The estimated surfacecharge density of the protoplasts isolated from elongating regionsof Vigna mungo root was 39 ? 8 mC/m2. The negative surfacecharge density increased when protoplasts were treated withglutaraldehyde or when EDTA was added to the protoplast suspensionmedium. These results support the validity of our estimationof the surface charge density of protoplasts by the 9-aminoacridinemethod. The concentration of amino groups at the surface ofthe protoplasts was estimated to be 34 mC/m2. (Received June 19, 1987; Accepted April 11, 1988) 相似文献
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