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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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Surface antigens of Saccharomyces cerevisiae protoplast were visualized immunocytochemically with protein A-gold or ferritin conjugated antibodies. Ferritin particles were densely distributed at the surface of yeast protoplast after treatment with rabbit anti-protoplast serum and ferritin conjugated antibody against rabbit IgM. Control experiments demonstrated that the binding of these ferritin markers was specific for surface antigens. The composition of these surface antigens, however, remain to be investigated.  相似文献   
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T Hirano  K Oka  M Akiba 《Life sciences》1989,45(12):1111-1117
A comparative study was made of the effects of 15 synthetic and naturally occurring flavonoids on the hydrolytic activity of Na+, K+-adenosine triphosphatase (ATPase). Twelve of the flavonoids examined were mono-hydroxy or mono-methoxy derivatives. All inhibited Na+, K+-ATPase from dog kidney cortex when present at concentrations from 40-1000 microM. Flavones possessing cyclohexyl instead of the phenyl group (i.e., 2-cyclohexyl-benzopyran-4-one derivatives), were the most potent with IC50 at 257-320 microM. Structure-activity relationships were observed among the following mono-substituted flavones as: i) 2-cyclohexyl-benzopyran-4-one much greater than 2-phenyl-benzopyran-4-one; ii) 2-cyclohexyl-7-hydroxybenzopyran-4-one greater than 2-cyclohexyl-6-hydroxybenzopyran-4-one greater than 2-cyclohexyl-5-hydroxybenzopyran-4-one. Some flavonoids showing potent inhibitory activity were also examined for ouabain-displacement activity on human erythrocytes. Hardly any of the flavonoids were able to block [3H]ouabain binding to erythrocytes. These results suggest that the mechanism by which flavonoid block Na+, K+-ATPase is not related to the cardiac glycoside-specific binding site(s) of this enzyme.  相似文献   
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The mechanism of placental alkaline phosphatase (PLAP) induction by prednisolone in a uterine cervical epidermoid cancer cell line SKG-IIIa was investigated in vitro by enzyme-cytochemistry, enzyme immunoassay, Northern and Southern blot analysis, and in situ hybridization. Enzyme-cytochemical alkaline phosphatase (ALP) staining and immunoassay revealed increased levels of PLAP (heat-stable ALP) in prednisolone-treated cells. Northern blot analysis and in situ hybridization showed increased amounts of PLAP mRNA. Southern blot analysis indicated that PLAP was not a product of an amplified or rearranged gene. These findings suggest that the induction of PLAP mRNA in SKG-IIIa cells by prednisolone in turn increased the levels of PLAP.  相似文献   
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The syntheses of copper, zinc-superoxide dismutase (Cu,Zn-SOD) and manganese-superoxide dismutase (Mn-SOD) in vitro were studied. Both Cu,Zn-SOD and Mn-SOD were preferentially synthesized by free polysomes. Mn-SOD was synthesized as a large precursor (26,000 daltons), which was processed to the mature size (22,500 daltons) by in vitro incubation with a rat liver mitochondrial fraction. On the other hand, Cu,Zn-SOD was synthesized as the mature size product. It was shown that Cu,Zn-SOD and Mn-SOD synthesized in vitro represented 0.018% and 0.016% of the total translation products of free polysomes, respectively.  相似文献   
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Fasting for 3?days leads to reduction in the expression of GLUT5 and SGLT1 genes in jejunum. Re-feeding a high-sucrose diet in fasted rats enhanced mRNA levels and histone H3 acetylation on transcribed region of GLUT5 gene within 24?h, but not in SGLT1. Responsiveness of jejunal GLUT5 gene is associated with changes in histone H3 acetylation on transcribed region.  相似文献   
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