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排序方式: 共有5083条查询结果,搜索用时 15 毫秒
1.
Kazuma Nakano Akino Shiroma Makiko Shimoji Hinako Tamotsu Noriko Ashimine Shun Ohki Misuzu Shinzato Maiko Minami Tetsuhiro Nakanishi Kuniko Teruya Kazuhito Satou Takashi Hirano 《Human cell》2017,30(3):149-161
PacBio RS II is the first commercialized third-generation DNA sequencer able to sequence a single molecule DNA in real-time without amplification. PacBio RS II’s sequencing technology is novel and unique, enabling the direct observation of DNA synthesis by DNA polymerase. PacBio RS II confers four major advantages compared to other sequencing technologies: long read lengths, high consensus accuracy, a low degree of bias, and simultaneous capability of epigenetic characterization. These advantages surmount the obstacle of sequencing genomic regions such as high/low G+C, tandem repeat, and interspersed repeat regions. Moreover, PacBio RS II is ideal for whole genome sequencing, targeted sequencing, complex population analysis, RNA sequencing, and epigenetics characterization. With PacBio RS II, we have sequenced and analyzed the genomes of many species, from viruses to humans. Herein, we summarize and review some of our key genome sequencing projects, including full-length viral sequencing, complete bacterial genome and almost-complete plant genome assemblies, and long amplicon sequencing of a disease-associated gene region. We believe that PacBio RS II is not only an effective tool for use in the basic biological sciences but also in the medical/clinical setting. 相似文献
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T Nimura M Okada M Shimizu M Kawabe T Itoh M Iwasaki H Kimura T Takeuchi 《The Annals of physiological anthropology》1990,9(4):329-333
Motorcyclists who work in some offices sometimes complained of coldness, pain and numbness of upper limbs. We studied how to discriminate between vibration syndrome and local fatigue of the motorcyclists. Subjects are 42 motorcyclists of an office in Aichi prefecture. 25 of them held several letters in their left hand when they delivered the letters. They complained of coldness, pain and numbness in the left upper limbs more than in the right limbs (p less than 0.01). We think that it is the local fatigue rather than the disorder of vibration syndrome that causes such symptoms. So it is very important to recognize the existence of local fatigue in order to know how to discriminate between vibration syndrome and local fatigue of the motorcyclists. 相似文献
4.
The defatted sclerotia powder was partially hydrolyzed with dilute acid, and the material obtained was fractionated by carbon column chromatography, separated into two disaccharides, three trisaccharides and three tetrasaccharides, respectively. In these hydrolyzates α, α-trehalose, Iaminaribiose, and gentiobiose were identified. 相似文献
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In this paper we consider the stability property of single-species patches connected by diffusion with a within-patch dynamics
of Volterra type and with continuous time delays. We prove that this system can only have two kinds of equilibria: the positive
and the trivial one. By the assumption that the delay kernels are convex combinations of suitable non-negative and normalized
functions, the linear chain trick gives an expanded system of O.D.E. with the same stability properties as the original integro-differential
system. Homotopy function techniques provide sufficient conditions for the existence of the positive equilibrium and for its
global stability. We also prove the local stability of any positive equilibrium and the local instability both of positive
and trivial equilibria. The biological meanings of the results obtained are compared with known results from the literature.
This work was performed under the auspices of G.N.F.M., C.N.R. (Italy) and within the activity of the Evolution Equations
and Applications group, M.P.I. (Italy).
I thank the Department of Applied Mathematics, Shizuoka University, Japan, which enabled me to visit Urbino. 相似文献
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Using the cornea of macaque monkey, we demonstrated the relationship between cell density and growth of endothelial cells in vitro. Corneal endothelial cells in a cell sheet grow most actively in regions with cell density of 1000 to 1800 cells/mm2, in explant cultures and cell sheets and in concentrated inocula dissociated cells. Cell morphology was well sustained in these cultures. Cells cultured at a higher cell density retained their potential to proliferate actively, showing clear contrast to cells cultured at a density lower than 200 cells/mm2. When dissociated cells were cultured at a low density and maintained for more than 4 weeks, they gradually lost their growth potential, altered into polymorphonuclear giant cells and eventually dedifferentiated. In addition, cells with no contact with each other did not express growth potential. Density dependent growth was confirmed by measuring the mitotic index against the cell density per square mm from the center to the peripheral regions in cultured explants. It is concluded that the growth pattern of corneal endothelial cells is closely related to cell density, and that growth of these cells might be regulated through intercellular communications. 相似文献
9.
Yukio Ishimi Masatoyo Kojima Fujio Takeuchi Terumasa Miyamoto Masa-Atsu Yamada Fumio Hanaoka 《Experimental cell research》1987,169(2):458-467
Human skin fibroblasts from embryo, 16-, 30- and 60-year-old adults were cultivated and passaged in vitro. Their chromatin structures were examined by the sensitivity to micrococcal nuclease and by electron microscopy. When the mode of DNA degradation by the nuclease was analysed during in vitro aging of the embryo skin fibroblasts, the discrete ladder of nucleosomal DNA became obscure in old cells. Analogous change of chromatin structure was also observed even in young cells as their donor ages increased. From the observation with electron microscopy, it became clear that chromatin of fibroblasts from 30-year-old adults does not have regularly spaced nucleosomes, compared with chromatin from embryo. These results suggest that the length of the linker DNA which connects core particles becomes to be heterogeneous by aging, both in vivo and in vitro in human skin fibroblasts. 相似文献
10.
Y Takeuchi T Okumura J Sugatani K Saito 《Archives of biochemistry and biophysics》1987,252(1):206-217
Two types of phospholipase B of Penicillium notatum, the native type and the modified type that is thought to be generated by the introduction of some nicks into the native type of enzyme by the endogenous protease(s), were distinguished on a slab sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis under a nonreducing condition. The native form migrated with a rate corresponding to 95K Da, whereas the modified form migrated more slowly, corresponding to 106K Da, presumably because of its more extended conformation. That the "106K" protein was indeed a nicked product of the "95K" protein was confirmed by amino acid analysis, peptide mapping, N- and C-terminal sequence analyses, and immunoblotting. The peptide fragments (70K and 37K + 32K) comprising the modified protein were isolated by gel filtration in the presence of SDS and 2-mercaptoethanol (the 32K peptide was suggested to be a partial proteolytic product of the 37K peptide). When the "95K" protein was subjected to the same treatment under denaturing condition, it retained a low, but significant, enzymatic activity; in contrast, the separated peptide fragments did not show any significant activity. By a coincubation of these fragments, however, a restoration of enzymatic activity was observed through a reformation of the active complex, corresponding to the original modified protein. The enzymatic activity of this complex was further increased by a treatment with guanidine X HCl, followed by dialysis. The association of peptide fragments appears to occur through the formation of interpeptidal disulfide bonds. 相似文献