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11.
Kiyoshi Takamuku Tsuyoshi Akiyoshi Hideo Tsuji 《Cancer immunology, immunotherapy : CII》1987,25(2):137-140
Summary Antibody-dependent cell-mediated cytotoxicity (ADCC) mediated by a murine monoclonal antibody against human colerectal carcinoma, antibody 19–9, with human effector cells was tested in 33 patients with various carcinomas, 16 patients with benign lesions, and 13 normal controls, using a 12-h 51Cr release assay using human colorectal cancer cells as targets. Peripheral blood mononuclear cells (PBM) from these groups of patients and normal controls achieved moderate levels of target cell lysis in the presence of the monoclonal antibody at the high effector to target cell ratio of 200:1. The ADCC activity of PBM in cancer patients was significantly higher than that in either normal persons or patients with benign lesions. Since the ADCC was shown to be mainly mediated by adherent monocytes in the PBM, ADCC activity of monocytes from cancer patients was compared to those from control groups at an effector to target cell ratio of 30:1. The results also showed that the lytic capacity of monocytes was significantly higher in cancer patients than that in the control populations. 相似文献
12.
Hiroshi Iwasaki Toshikazu Shiba Atsuo Nakata Hideo Shinagawa 《Molecular & general genetics : MGG》1989,219(1-2):328-331
Summary The ruv operon of Escherichia coli consists of two genes, orfl1 and ruv, which encode 22 and 37 kilodalton proteins, respectively, and are regulated by the SOS system. Although the distal gene, ruv, is known to be involved in DNA repair, the function of orf1 has not been studied. To examine whether orf1 is also involved in DNA repair, we constructed a strain with a deletion of the entire ruv operon. The strain was sensitive to UV even after introduction of low copy number plasmids carrying either orf1 or ruv, but UV resistance was restored by introduction of a plasmid carrying both orfl and ruv. These results suggest that orf1 as well as ruv is involved in DNA repair. Therefore, orf1 and ruv should be renamed ruvA and ruvB, respectively. 相似文献
13.
Kazuyuki Tao Kozu Makino Shuji Yonei Atsuo Nakata Hideo Shinagawa 《Molecular & general genetics : MGG》1989,218(3):371-376
Summary Treatment of Escherichia coli and Salmonella typhimurium cells with a low dose of hydrogen peroxide induces expression of a large number of genes, and confers resistance to oxidative stresses. The oxyR gene encodes a positive regulatory protein for a subset of these genes involved in the defense against oxidative damage. We cloned a DNA fragment that contains the E. coli oxyR region on a plasmid vector, and analyzed the nucleotide sequence of the gene. The amino acid sequence of OxyR protein, deduced from the nucleotide sequence, shows a high degree of homology to the sequences of a number of bacterial activator proteins including LysR, cysB, IlvY, MetR and NodD. The product of the oxyR gene identified by the maxicell procedure was a 34 kDa protein, which agrees with the size predicted from the nucleotide sequence of the gene. 相似文献
14.
A few reports have suggested the possibility that feeding conditions might affect the sexual maturation of free-ranging Japanese
monkeys in provisionized troops. In the present study, the sexual maturation of male monkeys at Takasakiyama in 1984, nine
years after the start of restriction of artificial feeding, was examined externally and histologically and the results were
compared with data obtained in 1971, when artificial foods were abundantly given. Spermatogenesis was not observed in any
of the males under 4.5 years old in the present study, whereas it was noted in some premature 3.5-year-old males and in all
males over 4.5 years old in the 1971 study. The age of sexual maturation thus rose by one or more years over the 13-year period
from 1971 to 1984. The lag in sexual maturation of the males at Takasakiyama in 1984 could have been induced by the restriction
of artificial feeding. 相似文献
15.
Satoshi Mitsuda Shigeyasu Nabeshima Hideo Hirohara 《Applied microbiology and biotechnology》1989,31(4):334-337
Summary Characteristics of the enantioselective hydrolysis of the acetic ester of 4-hydroxy-3-methyl-2-(2-propynyl)-2-cyclopentenone (HMPC) by Arthrobacter lipase were investigated in a water/oil biphasic reaction mixture. Kinetic studies revealed that the strict enantioselectivity was entirely due to a difference in the catalytic constants for the enantiomeric substrates and that (S)-HMPC acetate acted as a competitive inhibitor. The comparison of enantioselectivity for the acetates of HMPC analogues indicated that hydrophobic substituents in the HMPC molecule were essential for the strict enantioselectivity.Biological preparation of an optically active alcohol. Part II 相似文献
16.
Tadao Arinami Takeki Hirano Kimiko Kobayashi Yasuko Yamanouchi Hideo Hamaguchi 《Human genetics》1990,85(1):39-40
Summary The XmnI genotype at the apolipoprotein A-I locus was heterozygous in a boy with partial deletion of the long arm of chromosome 11, del(11)(q23.3qter). The apolipoprotein A-I gene, previously assigned to chromosome region 11q23q24, has been more specifically localized to 11q23 by excluding the region 11q24qter. 相似文献
17.
The effects of different light regimes on the survival, growth and morphology ofQuercus serrata seedlings were studied in canopies ofMiscanthus sinensis. The seedlings of various ages (0–3 yr) were grown in three light regimes: under a denseM. sinensis canopy (TG plot) receiving 2.5%–8.7% of full sunlight, under a relatively sparse canopy (SG plot) receiving 3.8%–16.1% of
light and in an adjacent open site (NG plot). There was a little difference in the survival ofQ. serrata seedlings among the three plots. Height and diameter of stem and total leaf area of the seedlings were significantly lower
in the shadier plots. However, the first (bottom) flush of the stem was significantly longer in the TG plot than in the NG
and SG plots. Total dry weights of individual 1- and 2-yr-oldQ. serrata seedlings in the TG plot were reduced to about one-twelfth of those in the NG plot. Although the relative proportion in dry
weight of each organ did not differ significantly among the plots, leaf area ratio, specific leaf area and stem height per
unit dry weight were significantly higher in shadier plots. The leaf area per unit stem height was increased considerably
in the sunnier plots. 相似文献
18.
Human T cells are stimulated with an autologous mixed leukocyte reaction (AMLR) and can be propagated in interleukin-2. Staining of the cultured cells with the combination of two monoclonal antibodies was evaluated by two-dimensional flow cytometry at weekly intervals. AMLR activation resulted in an initial preservation of the CD4+ (helper/inducer T) subset predominance over the CD8+ (suppressor/cytotoxic T) cells, noted on normal circulating blood lymphocytes. However, during culture in interleukin-2, there was a progressive increase in the percentages of CD8+ Leu 15- cytotoxic T, CD4+ Leu 8- helper T, and CD3+ HLA-DR+ activated T cells, and a concomitant decrease in those of CD4+ Leu 8+ suppressor inducer T and CD8+ Leu 15+ suppressor T cells if the responder sheep red blood cell (SRBC)-rosetting T cells were made up by tris ammonium chloride, but not by hypotonic shock treatment to lyse SRBC. The significant difference between hypotonic shock-T cells and ammonium chloride-T cells in the phenotypic changes of T cell subsets after long-term culture in an interleukin-2 medium may suggest a regulatory role of the ammonium chloride-sensitive T cells in the AMLR. 相似文献
19.
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
20.
The molybdenum-iron component of nitrogenase (Mo-Fe component)was purified from soybean nodule bacteroids and antibody wasraised against it in rabbits. Antibody raised against the 53kDa polypeptide which was the major protein in the Mo-Fe componentfraction of soybean nitrogenase was confirmed to be specificto the nitrogenase by immunodiffusion and immunotitration. Thenitrogenase from root nodules of Elaeagnus pungens cross-reactedwith the antibody and appeared from the results of the immunodiffusionto be partially identical to soybean nitrogenase. Using the antibody, we examined intracellular localization ofnitrogenase in root nodules of Elaeagnus pungens, in which Frankiais present as a symbiont, by immuno-gold labelling. Thin sectionsof nodules of Elaeagnus pungens were first treated with anti-nitrogenasespecific antibody and then with colloidal gold-protein A asa marker. The gold particles were observed to be concentratedin the vesicles of the endophyte Frankia. This provides strongsupport for the existence E of nitrogenase in the vesicles.Furthermore, our results suggested that nitrogenase localizesin the hyphae of the endophyte Frankia in Elaeagnus pungensnodules.
1Present address: Iwata Experiment Station, Japan Tobacco Inc.,Iwata-gun, Shizuoka 438, Japan. (Received March 9, 1988; Accepted July 28, 1988) 相似文献