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991.
Katsuhiko Kondo Takehisa Nakamura Twesukdi Piyakarnchana Wina Mechvichai 《Plant Species Biology》1991,6(2):105-109
Abstract The bird species Hypsipetes amaurotis and Zosterops palpebrosa var. yonakuni , but no insects, were recorded regularly feeding on flower-nectar of Bruguiera gymnorrhiza in the Miyara River Biological Preserve, Ishigaki Island, Japan, at 7:00-9:15 a.m. during the investigation from December 20, 1987, to January 19, 1988. In contrast, Anthreptes malacensis foraged for nectar from 7:00 a.m. to 17:00 p.m. Oriolus chinensis visited the flowers mainly between 6:30 and 7:30 a.m. in Phangnga, Thailand, during the investigation from November 30 to December 19, 1986. Pollen grains were sprayed onto the birds'faces and bills and into the air. The highest mean volume of 0.24 pollen grains/ l /minute was triggered in calm air by the most frequent nectarivore between 6:45 and 7:00 a.m. at a height of 1.5m under a tree-branch carrying 145 fresh flowers in the Miyara River population, Japan. The highest mean volume of 0.27 pollen grains/ l /minute under the same conditions in the Phangnga population, Thailand. Bruguiera gymnorrhiza is bird-pollinated but with the possibility of some pollination indirectly by wind. 相似文献
992.
Two children with juvenile rheumatoid arthritis (JRA) were given photosensitive dye Platonin in combination with prednisolone. Analysis of clinical and laboratory data showed that Platonin was efficacious in the improvement of the clinical symptoms and the severity of inflammation, or in the maintenance of the remission state. There were no adverse side effects during long-term administration of medication. 相似文献
993.
Phylogenetic affiliation of ancient and contemporary humans inferred from mitochondrial DNA. 总被引:4,自引:0,他引:4
S Horai R Kondo K Murayama S Hayashi H Koike N Nakai 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》1991,333(1268):409-16; discussion 416-7
Nucleotide sequence analysis of the major non-coding region of human mitochondrial DNA (mtDNA) from three major races was extended with data from 27 contemporary Mongoloids (20 from southeast Asia, seven from America) and 11 Ancient Japanese bones (five from Jomon Age; 3000-6000 years BP, six from the early modern Ainu; 200-300 years BP). In both cases, the sequence was determined directly from the polymerase chain reaction products. Based on a comparison of the 482 base pair sequences from a total of 128 contemporary humans, the nucleotide diversity is estimated to be 1.46%, which is three times higher than the corresponding value estimated from restriction-enzyme analysis of the whole mtDNA genome. The phylogenetic tree revealed that all lineages are classified into at least five clusters designated as C1-C5. C1 consists exclusively of Africans, and most Asians and Europeans formed C2, C3, C5 and C4, respectively. Phylogenetic analysis also indicated that part of the Asians, including the Japanese, subsequently diverged from the majority of Africans, and that Asians can therefore be separated into two distinct groups. Native Americans, however, appeared only in C3 and C5, suggesting that the size of the founder population was not so large during the peopling of American. Nucleotide sequences derived from ancient bones in a highly polymorphic region were also compared with those of contemporary humans. The nucleotide diversity among the 139 sequences in the region was estimated to be 2.26%. A group of ancient Japanese, including both Jomon peoples and the Ainu, showed a close phylogenetic affiliation with one group of contemporary Japanese and southeast Asians.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
994.
995.
Hideki Ohno Takahito Kondo Yutaka Fujiwara Sei-ichi Tagami Akihiro Kuroshima Yoshikazu Kawakami 《International journal of biometeorology》1991,35(2):111-113
Effects of acute and chronic cold stress on glutathione and related enzymes in rat erythrocytes were investigated. Blood from both cold-acclimated (CA) and cold-adapted (CG) rats had significantly lower concentrations of glutathione than blood from control animals. Superoxide dismutase activity was increased significantly in CA rats and tended to rise in CG rats. Activity of glutathione peroxidase in erythrocytes was inconsistent in that it tended to increase in CA rats but decreased significantly in CG rats. The results may imply that CG rats suffered deleterious effects of hydrogen peroxide. On the other hand, there were marked decreases in glutathione peroxidase and glutathione reductase activities in acutely cold-exposed rats in conjunction with unchanged levels of glutathione. In all treatments the state of riboflavin metabolism was estimated to be adequate, since no increases were observed in the erythrocyte glutathione reductase activity coefficient. 相似文献
996.
Suppression of lipoprotein lipase in 3T3-L1 cells by a mediator produced by SEKI melanoma, a cachexia-inducing human melanoma cell line 总被引:1,自引:0,他引:1
M Kawakami Y Kondo Y Imai M Hashiguchi H Ogawa A Hiragun S Aotsuka S Shibata T Oda T Murase 《Journal of biochemistry》1991,109(1):78-82
Production of a cachexia-inducing factor(s) by the SEKI melanoma cell line, established from a human melanoma, has been well documented. Conditioned medium from cultures of this melanoma cell line contains a factor(s) that inhibits the activity of lipoprotein lipase (LPL) in fully differentiated 3T3-L1 adipocytes. The mode of inhibition of this enzyme by the factor, i.e. its dose-dependency and time course, is very similar to that of LPL-inhibition by a macrophage-derived cachexia-inducing factor, cachectin/tumor necrosis factor (cachectin/TNF). However, the conditioned medium of SEKI melanoma cells does not contain any immuno-reactive substances reactive in enzyme-linked immunosorbent assay (ELISA) with anti-cachectin/TNF antibody, or with anti-interleukin 1 alpha or beta antibodies. This LPL-suppression factor present in the conditioned medium seems to be a peptide because of its heat-lability and apparent molecular weight of more than 25,000. The conditioned media from cultures of four other different cell lines were found to show no significant suppression of LPL activity. These results imply that SEKI melanoma cells produce a cachexia-inducing factor(s) similar to cachectin/TNF but that the molecule involved is different. 相似文献
997.
Detection of lipopolysaccharide-binding proteins on membranes of murine lymphocyte and macrophage-like cell lines 总被引:3,自引:0,他引:3
998.
A coat-color mutant was found in the wild musk shrew (Suncus murinus, Insectivora). Five musk shrews with gray pelage, the common coat color of this species, were captured in the village of Tambum near Jakarta, Indonesia. Two males and two females were transported to Japan and mated. Matings between one male and two females segregated several cream-colored offspring, a color that had never been seen before in this species. From the pedigree record and data on mating experiments, it was confirmed that this mutant coat color was expressed in the homozygote by an autosomal recessive gene designated cr, and at least three of the four wild shrews examined were carriers of this gene. The cr gene was associated with failure of normal pigmentation in the pelage and skin. The mutant shrews also showed some behavioral abnormalities. 相似文献
999.
S Nakao M Harada K Kondo K Odaka M Ueda K Matsue T Mori K Hattori 《Journal of immunology (Baltimore, Md. : 1950)》1984,132(1):160-164
We studied the effects of alloantigen-stimulated lymphocytes in the regulation of hematopoiesis. Alloantigen-stimulated lymphocytes were harvested on days 2 to 3, days 6 to 7, or days 9 to 10 of MLC and were tested for their effects on granulocyte/macrophage progenitor cells (CFU-C). Dose-dependent suppression of CFU-C was observed when alloantigen-stimulated lymphocytes from days 6 to 7 and days 9 to 10 MLC were added to the cultures of autologous or allogeneic bone marrow cells for CFU-C assays. Suppressive activity was detected in the T cell fraction but not in the non-T cell fraction. For further characterization of these CFU-C/suppressor cells, alloantigen-stimulated lymphocytes were treated with radiation (2000 rad) or with monoclonal antibodies against T cell subsets and complement (C) before culture. Suppressive activity was completely abolished by treatment with OKT8 or OKIa1 antibodies and C whereas suppression was retained after radiation treatment. These observations suggest that CFU-C/suppressor cells can be induced by alloantigen stimulation in MLC and that they are radioresistant OKT8+ and Ia+ T cells. 相似文献
1000.
Plasmid transformation of Streptococcus lactis protoplasts: optimization and use in molecular cloning 总被引:17,自引:0,他引:17
The parameters affecting polyethylene glycol-induced plasmid transformation of Streptococcus lactis LM0230 protoplasts were examined to increase the transformation frequency. In contrast to spreading protoplasts over the surface of an agar medium, their incorporation into soft agar overlays enhanced regeneration of protoplasts and eliminated variability in transformation frequencies. Polyethylene glycol with a molecular weight of 3,350 at a final concentration of 22.5% yielded optimal transformation. A 20-min polyethylene glycol treatment of protoplasts in the presence of DNA was necessary for maximal transformation. The number of transformants recovered increased as the protoplast and DNA concentration increased over a range of 3.0 X 10(6) to 3.0 X 10(8) protoplasts and 0.25 to 4.0 micrograms of DNA per assay, respectively. With these parameters, transformation was increased to 5 X 10(3) to 4 X 10(4) transformants per microgram of DNA. Linear and recombinant plasmid DNA transformed, but at frequencies 10- to 100-fold lower than that of covalently closed circular DNA. Transformation of recombinant DNA molecules enabled the cloning of restriction endonuclease fragments coding for lactose metabolism into S. lactis LM0230 with the Streptococcus sanguis cloning vector, pGB301. These results demonstrated that the transformation frequency is sufficient to clone plasmid-coded genes which should prove useful for strain improvement of dairy starter cultures. 相似文献