Restriction Ring
Mostrando 1-12 de 34 artigos, teses e dissertações.
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1. Investigação da reação de Morita-Baylis-Hillman em reator de micro-ondas usando aldeídos aromáticos e isatina como eletrófilos: avaliação da atividade citotóxica em linhagem de células de leucemia promielocítica humanas (HL-60). / Investigation of Morita-Baylis-Hillman Reaction on Microwave Reactor using Aromatic Aldehydes and Isatin as Eletrophiles: Evaluation of Cytotoxic Activity in cell line human promyelocytic leukemia (HL-60).
In this work, we describe the investigation of the Morita-Baylis-Hillman reaction in microwave reactor, under closed vessel conditions to prepare 40 adducts, six novel, using 30 aromatic aldehydes and isatin as electrophiles and acrylonitrile (62a) , methyl acrylate (2), hydroxyethyl acrylate (62b), 2,2-dimethyl-1 ,3-dioxalyl acrylate (62c) and 2,3-dihydroxy
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 14/11/2012
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2. Nitretação em plasma com gaiola catódica: caracterização e avaliação do desempenho da camada nitretada em facas de corte
Atualmente, na indústria de plásticos são utilizados moinhos que realizam a reciclagem dos resíduos gerados na produção de seus componentes. Esses moinhos contêm lâminas de corte que sofrem desgaste acelerado, uma vez que são constantemente submetidas a esforços tribológicos, diminuindo sua vida útil. Para amenizar este problema, são utilizados
Publicado em: 2007
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3. Um estudo topologico sobre aneis de valorização de Dubrovin
Dubrovin valuation rings in simple artinian rings are studied topologically. The motivation is the Theorem due to Kowalski and Dürbaum which ensures that any V-topology over a field is generated by means of a valuation ring or an absolute value of the field. Beginning from Dubrovin valuation ring R in the simple artinian ring Q, a topology namely R-ideal to
Publicado em: 1998
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4. Detection and characterization of a ring chromosome in the fission yeast Schizosaccharomyces pombe.
NotI and SfiI genomic restriction maps were used to detect and characterize a ring chromosome II in a Schizosaccharomyces pombe strain with a meiotic defect on chromosome II. The ring chromosome was formed by an intrachromosomal fusion near, or at, the very ends of chromosome II.
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5. Recombination by resolvase to analyse DNA communications by the SfiI restriction endonuclease.
The SfiI endonuclease differs from other type II restriction enzymes by cleaving DNA concertedly at two copies of its recognition site, its optimal activity being with two sites on the same DNA molecule. The nature of this communication event between distant DNA sites was analysed on plasmids with recognition sites for SfiI interspersed with recombination si
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6. The McrBC restriction endonuclease assembles into a ring structure in the presence of G nucleotides
McrBC from Escherichia coli K-12 is a restriction enzyme that belongs to the family of AAA+ proteins and cuts DNA containing modified cytosines. Two proteins are expressed from the mcrB gene: a full-length version, McrBL, and a short version, McrBS. McrBL binds specifically to the methylated recognition site and is, therefore, the DNA-binding moiety of the M
Oxford University Press.
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7. DNA flexibility studied by covalent closure of short fragments into circles.
The ring closure probability, or j factor, has been measured for DNA restriction fragments of defined sequence bearing EcoRI cohesive ends and ranging in size from 126 to 4361 base pairs (bp). The j factor is defined as the ratio of the equilibrium constants for cyclization and for bimolecular association via the cohesive ends. The end-joining reactions are
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8. SURVEY AND SUMMARY: Difference in conformational diversity between nucleic acids with a six-membered ‘sugar’ unit and natural ‘furanose’ nucleic acids
Natural nucleic acids duplexes formed by Watson–Crick base pairing fold into right-handed helices that are classified in two families of secondary structures, i.e. the A- and B-form. For a long time, these A and B allomorphic nucleic acids have been considered as the ‘non plus ultra’ of double-stranded nucleic acids geometries with the only exception o
Oxford University Press.
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9. Investigation of restriction-modification enzymes from M. varians RFL19 with a new type of specificity toward modification of substrate.
The characterization of MvaI restriction-modification enzymes, isolated from Micrococcus varians RFL19, is reported. Both enzymes recognize the 5'CC decreases (A/T)GG nucleotide sequence. The endonuclease cleaves the sequence at the position indicated by the arrow, whereas the methylase modifies the internal cytosine, yielding N4-methylcytosine. This type of
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10. Chromatin structure of a hyperactive secretory protein gene (in Balbiani ring 2) of Chironomus.
We examined the chromatin structure of a Balbiani ring (secretory protein gene) in the salivary glands of Chironomus larvae in its hyperactive state after stimulation with pilocarpine. For the inactive state of the gene an established tissue culture cell line, not expressing the gene, was used. Electron microscopy showed an RNA polymerase density of approxim
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11. Oxybuprocaine keratopathy: a preventable disease.
Topically applied anaesthetics may lead to a serious keratopathy. Three patients presented to us with disciform keratitis, peripheral corneal ring, and stromal infiltration following the topical use of oxybuprocaine. All three patients developed marked decrease in vision secondary to corneal scarring. In all three patients oxybuprocaine was dispensed over th
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12. The Giardia lamblia trophozoite contains sets of closely related chromosomes.
Size variations in homologous chromosomes from six Giardia lamblia isolates have been demonstrated. Four or five intensely stained (major) bands as well as a variable number of lightly stained (minor) bands are present in pulsed field gradient separations. Southern blot analysis with total chromosomal DNA as well as chromosome specific probes indicates that