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1.
Toshitaro Morinaga 《American journal of botany》1926,13(2):126-140
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A fibroblast-derived tumor cytotoxic factor/F-TCF (hepatocyte growth factor/HGF) has multiple functions in vitro. 总被引:2,自引:0,他引:2
N Shima Y Itagaki M Nagao H Yasuda T Morinaga K Higashio 《Cell biology international reports》1991,15(5):397-408
We previously demonstrated that a tumor cytotoxic factor(F-TCF) purified from the culture broth of human embryonic lung diploid fibroblast, IMR-90 cells was one of the human hepatocyte growth factors (hHGFs). In the present report, we demonstrate its biological functions. F-TCF showed moderate cytotoxicity on human tumor cell lines KB, BG-1, MCF-7 and Hs913 T, and strong cytotoxicity on mouse tumor cell lines Sarcoma 180, Meth A sarcoma and P388. On the contrary, F-TCF was a potent mitogen not only for adult rat hepatocytes, but also for human endothelial cells, HUVEC and human melanocytes. Moreover, F-TCF induced the differentiation of premyelocyte leukemia, HL-60 cells into morphologically granulocyte-like cells. These biological functions suggest that F-TCF is an effector molecule responsible for inflammation and repair in injured tissues including tumor and liver. 相似文献
4.
The human alpha-fetoprotein gene. Sequence organization and the 5' flanking region 总被引:12,自引:0,他引:12
M Sakai T Morinaga Y Urano K Watanabe T G Wegmann T Tamaoki 《The Journal of biological chemistry》1985,260(8):5055-5060
The human alpha-fetoprotein (AFP) gene was isolated into three overlapping clones in bacteriophage lambda vectors and its sequence organization analyzed by restriction endonuclease mapping and nucleotide sequencing. The human AFP gene is about 20 kilobase pairs long and contains 15 exons and 14 introns. The overall organization of the human AFP gene is similar to that of the mouse AFP gene, with all but two exons showing identical sizes. Nucleotide sequences at all exon/intron junctions display similarity to the consensus boundary sequence (Breathnach, R., and Chambon, P. (1981) Annu. Rev. Biochem. 50, 349-383), with the GT-AG rule applied to the splicing point. The cap site maps 44 nucleotides upstream from the translation initiation site. The "TATA box" is located 27 nucleotides upstream from the putative cap site and is flanked by sequences with dyad symmetry. The TATA box can thus be placed in the loop portion of a possible stem-loop structure formed by intrastrand base-pairing. Other characteristic nucleotide sequences in the 5' flanking region include a CCAAC pentamer, a 14-base pair (bp) enhancer-like sequence, and a 9-bp sequence homologous to the glucocorticoid responsive element. A long (90 bp) direct repeat and several alternating purine/pyrimidine sequences are also present in the 5' flanking region. A 736-bp sequence of the 5' flanking region adjacent to the cap site of the human AFP gene shows a 61% similarity with the corresponding region of the mouse AFP gene. There are two Alu family sequences and two poly(dT-dG) repeats in the human AFP gene that show different distribution patterns from those in the mouse AFP gene. 相似文献
5.
Masanori Kasahara Toshinao Takenouchi Kazumasa Ogasawara Hitoshi Ikeda Tsuguyo Okuyama Naoshi Ishikawa Junko Moriuchi Akemi Wakisaka Yuko Kikuchi Miki Aizawa Takehisa Kaneko Noboru Kashiwagi Yasuharu Nishimura Takehiko Sasazuki 《Immunogenetics》1983,17(5):485-495
To study the gene products of the HLA complex, we produced two monoclonal antibodies, termed HU-18 and HU-23. They were active in complement-dependent cytotoxicity and detected B-cell alloantigens encoded by a locus (or loci) linked to HLA. When three types of HLA-DR4 homozygous B-cell lines with different HLA-D specificities were tested for reactivity with HU-18 and HU-23, they displayed distinct reaction patterns depending on the HLA-D specificities they possessed: EBV-Wa (HLA-DYT homozygous), negative for both HU-18 and HU-23; KT2 and KOB (HLA-DKT2 homozygous), positive only for HU-18; and ER (HLA-Dw4 homozygous), positive for both. These differential reaction patterns were further confirmed by testing against a panel of 17 HLA-DR4-positive peripheral blood lymphocytes with known HLA-D specificities. Thus, these monoclonal antibodies allow us to identify HLA-DYT, HLA-DKT2, and HLA-Dw4 solely by serologic methods. This is the first clearcut serologic identification of these three HLA-DR4-associated HLA-D specificities, which have been indistinguishable by conventional serology and identified only by cellular techniques. It is hoped that immunochemical investigations using HU-18 and HU-23 will advance our understanding of the HLA-D region on a molecular level. 相似文献
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Akira Nomura Yuko Yamazaki Takashi Tsuji Yukishige Kawasaki Shoji Tanaka 《Experimental cell research》1996,227(2):256
For all biological particles such as cells or cellular organelles, there are three-dimensional coordinates representing the centroid or center of gravity. These coordinates and other numerical parameters such as volume, fluorescence intensity, surface area, and shape are referred to in this paper as geometric properties, which may provide critical information for the clarification ofin situmechanisms of molecular and cellular functions in living organisms. We have established a method for the elucidation of these properties, designated the three-dimensional labeling program (3DLP). Algorithms of 3DLP are so simple that this method can be carried out through the use of software combinations in image analysis on a personal computer. To evaluate 3DLP, it was applied to a 32-cell-stage sea urchin embryo, double stained with FITC for cellular protein of blastomeres and propidium iodide for nuclear DNA. A stack of optical serial section images was obtained by confocal laser scanning microscopy. The method was found effective for determining geometric properties and should prove applicable to the study of many different kinds of biological particles in three-dimensional space. 相似文献
8.
Takeshi Minami Masayo Ichii Yoshiyuki Tohno Setsuko Tohno Masako Utsumi Masa-oki Yamada Yuko Okazaki 《Biological trace element research》1996,55(1-2):199-205
The purpose of this study was to determine the extent of aluminum (Al) accumulation in the human aorta and cerebral arteries.
The Al contents in the aortae and in the cerebral arteries from 23 human subjects was determined by inductively coupled plasma
atomic emission spectrophotometry (ICP-AES). The subjects' age range was 45–99-yr-old; 15 of the subjects were males and 8
were females. Al was detected in twelve aortae and in six cerebral arteries, when the entire specimen was analyzed. Two specimens
where Al was found in the cerebral arteries contained no Al in the aorta. No relationship to the subject's sex was found.
When related to age, two groups were established. Group L (45–75 yr old) and group H (>75 yr old), which exhibited aortal
Al concentrations of 33.3 and 72.7%, respectively. When the aortic wall was dissected into the tunica intima, media, and adventitia,
Al was found mainly in the tunica media. In the aorta, significant relationships were found between Al and phosphorus (P)
levels (r=0.801,p<0.01) and between Al and calcium (Ca) (r=0.661,p<0.05). We have concluded that Al accumulation is age-dependent and that it occurs both in the aorta and in the cerebral artery.
In the aorta, accumulation occurs mainly in the tunica media. Both P and Ca appear to enhance aortal Al accumulation. 相似文献
9.
A smut fungus onPrimula sieboldii was newly found in Japan and identified asUrocystis tranzscheliana by comparative morphology. This species causes systemic infection ofP. sieboldii and produces sori in its ovaries.Contribution No. 121, Laboratories of Plant Pathology and Mycology, Institute of Agriculture and Forestry, University of Tsukuba. 相似文献
10.
The fungal succession on pine cones on the floor ofPinus densiflora forest was investigated in the early decomposition process (within ca. 30% decrease in dry weight). The fungal flora was examined by both washing and surface-sterilization methods on artificially placed cones and naturally fallen cones. The decomposition rates of artificially placed cones were 0.081–0.082 yr–1. On withered cones still attached to the tree,Pestalotiopsis spp. were dominant. These fungi also occurred with higher frequencies after cones had lain on the floor and on cones in the L and FH horizons.Xylaria sp. andPhomopsis sp., which seem to colonize the interior of the tissue, occurred with higher frequencies on the cones on the tree, but their occurrence frequencies decreased after cones had lain on the forest floor. Conversely,Mortierella spp. andTrichoderma spp. newly occurred or their occurrence frequencies increased on lying cones. Of these,Trichoderma koningii increased rapidly and showed high occurrence frequencies.Thysanophora penicillioides, which prefers coniferous substrates, showed higher occurrence frequencies in the early stages of lying on the forest floor. On cones lying on the floor, the fungal flora did not significantly change during the investigation period. 相似文献