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Summary A case of ring chromosome 15 passed on to the index patient's two children is reported, and possible reasons for the infrequent records of inheritance of ring chromosome are suggested.  相似文献   
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Summary We have previously reported the transformation by Rous sarcoma virus of a cloned epithelial cell line (BRL) established from Buffalo rat liver by H. Coon. The nontransformed (BRL) and transformed (RSV-BRL) cells grew at comparable rates in culture, whereas only the transformed cells were tumorigenic in vivo. We report here on the existence in rat and mouse sera of a growth inhibitor for the nontransformed BRL cells. The transformed BRL cells (RSV-BRL) were insensitive to this inhibitor. The inhibitory activity was not prominent in sera from other species of animals tested except for rabbit; this serum inhibited the growth of RSV-BRL cells more strongly than that of BRL cells. The growth inhibitor was partially purified from rat serum. It is a protein free of lipid and has a molecular weight of about 220 000. The inhibitor could be separated into three components of pI 4.6, 5.2 (major) and 5.6 by isoelectric electrophoresis. EDITOR'S STATEMENT Although compelling theoretical arguments sometimes can be made for the likely existence of growth-inhibitory substances of physical relevance in the control of cell proliferation, experiments aimed at identifying and studying such factors often are difficult to design and interpret, and little strong data exists to suggest that growth-inhibitory substances are important regulatorsin vivo. The information presented in this paper represents a start toward developing a useful system for studying growth-inhibitory factor. David W. Barnes  相似文献   
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Dispersion capabilities of new queens were studied in the two haplometrotic paper wasps Polistes riparius and P. snelleni. New queens were marked on the nests in the late summer and located in the next spring. Dispersion distances greatly varied among queens: although a large part of recovered queens nested in close proximity to their natal sites, some did disperse over 100–300 m. This suggests that queens' emigration from and immigration into the censused areas occurred to a substantial extent. On the whole, these species exhibited a weaker “philopatric” tendency than those so far studied for dispersion distance, and seem to have the potential for a long-distance dispersion.  相似文献   
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The noncoding region between tRNAPro and the large conserved sequence block is the most variable region in the mammalian mitochondrial DNA D-loop region. This variable region (ca. 270 bp) of four species of Equus, including Mongolian and Japanese native domestic horses as well as Przewalskii's (or Mongolian) wild horse, were sequenced. These data were compared with our recently published Thoroughbred horse mitochondrial DNA sequences. The evolutionary rate of this region among the four species of Equus was estimated to be 2–4 × 10–8 per site per year. Phylogenetic trees of Equus species demonstrate that Przewalskii's wild horse is within the genetic variation among the domestic horse. This suggests that the chromosome number change (probably increase) of the Przewalskii's wild horse occurred rather recently.Correspondence to: N. Ishida  相似文献   
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The late-glacial logistic decline of spruce (Picea) populations (the intrinsic growth rate,r in yr?1=?0.0015) was progressively delayed toward cooler sites in Japan; spruce populations expanded asymptotically (r=0.0040?0.0045) in Sakhalin early in the Holocene. Such a time-transgressive range shift in spruce distribution, covering a wide latitudinal range (ca. 35–50°N), implies that the regional temperature rise was not instantaneous, but was rapid, being 0.0015–0.0025 C yr?1 from 13,000 to 10,000 years B.P. Spruce populations increased in response to Neoglacial cooling only at the margin of its distribution (r=0.0036), but then declined logistically 1,000 years B.P. (r=?0.0022).  相似文献   
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The activity of 3-deoxy-D-arabino-heptulosonate 7-phosphate (DAHP) synthase (DS-Mn, DS-Co), phenylalanine ammonia-lyase (PAL), and chalcone synthase (CHS) was monitored at various light intensities (dark, 8.88 μmol m−2 s−1, 88.8 μmol m−2 s−1) using a strawberry cell suspension culture. DS-Mn, PAL, and CHS were found to increase significantly (p>0.05) under light intensitie of 88.8 μmol m−2 s−1 compared to those of 8.88 μmol m−2 s−1 and dark. The activity of DS-Mn, PAL, and CHS were maximum at 88.8 μmol m−2 s−1. Anthocyanin content reached a maximum after 48–60 h of culturing at 88.8 μmol m−2 s−1. DS-Co showed greater activity than DS-Mn during cell culturing, but showed no correlation with anthocyanin production and light intensity. The CHS gene expression was continuous at a light intensity of 88.8 μmol m−2 s−1. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
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We identified and characterized a gene encoding a protein that was 92% identical to human ribosomal protein L39. This gene was located on the long arm of chromosome 3, and was composed of three exons and two long introns. Analysis of mRNA expression in 16 types of normal human tissues showed that this gene was expressed specifically in the testis, in sharp contrast to the ubiquitous expression of the ribosomal protein L39 gene. Surprisingly, the new gene was expressed in 19 out of 24 human cancer samples of various tissue origins. When the new gene was expressed in the cell, a translated product was observed by immunofluorescence microscopy in the nucleus, especially strongly in the nucleolus, and in the cytoplasm. Association of this protein with the large subunit of cytoplasmic ribosomes was detected by polyacrylamide-agarose composite gel electrophoresis followed by immunodetection. These immunochemical data suggest a relationship between the new gene and the ribosome.  相似文献   
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