Tetramethylurea
Mostrando 1-12 de 21 artigos, teses e dissertações.
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1. Pure solvents and their mixtures solvation: relevance to chemistry and creen chemistry / Solvatação por solventes puros e suas misturas: relevância para química e química verde
In the present work, solvatochromic probes were employed in the study of pure solvents, binary mixtures of water with protic and aprotic solvents, ionic liquids and their aqueous binary mixtures The probes studied are classified in two series: (i) RPMBr2; where R = methyl to 1-octyl allowed increasing the hydrophobicity while maintaining the pKa constant. (i
Publicado em: 2008
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2. Transição sol-gel em soluções orgânico-aquosas de lisozima e o efeito indutor do solvente: caracterização cinética e estrutural / Sol-gel transition in aqueous-organic solutions of lysozyme and the solvent-inducing effect: a kinetic and structural characterization
Lysozyme sol-gel transition in tetramethylurea/water was investigated in depth. These dispersions produced highly viscous systems, which evolved to physical gels, i.e., systems where the gel backbone is maintained by van der Walls forces and hydrogen bonding. The work was conducted in two fronts: a) the study of lysozyme dispersions in binary mixtures; b) th
Publicado em: 2006
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3. Sintese, caracterização e termoquimicade adutos entre metil, N, N -dimetil e tetrametilureia com haletos de zinco, cadmio e mercurio-II
The reactions of zinc, cadmium and mercury halides with the ligands methylurea (MU), N,N´-dimethylurea (DMU) and tetramethylurea (TMU) yielded the following adducts: ZnL2X2, MLX2 (M = Cd, Hg) (X = Cl, Br and L = MU, DMU and TMU), M(TMU)2I2 (M = Zn, Cd), Cd(DMU)3Br3 and Hg(DMU)2Cl2. These adducts were characterized by elemental analyses, melting points, cond
Publicado em: 1980
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4. Primary Dysbetalipoproteinemia: Predominance of a Specific Apoprotein Species in Triglyceride-Rich Lipoproteins
Lipoproteins of very low density that are unusually rich in cholesteryl esters accumulate in blood plasma in a characteristic primary form of human hyperlipoproteinemia. These lipoproteins, which are thought to be products of the initial catabolic step in the metabolism of normal triglyceride-rich lipoproteins, have beta rather than pre-beta mobility on elec
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5. Comparison of immunoturbidimetric and Lowry methods for measuring concentration of very low density lipoprotein apolipoprotein B-100 in plasma.
To assess whether the Lowry-tetramethylurea method for measuring apolipoprotein B-100 (apo-B) in very low density lipoprotein (VLDL) could be replaced by direct assay of VLDL apo-B using a highly practicable immunological method. Seventy five fasting blood samples were collected from patients attending the lipid clinic at this hospital. Plasma was separated
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6. Radioimmunoassay of Human Apolipoprotein CII: A STUDY IN NORMAL AND HYPERTRIGLYCERIDEMIC SUBJECTS
A specific, precise, and sensitive double-antibody radioimmunoassay for the measurement of human apolipoprotein CII (apoCII) was developed. ApoCII was labeled with 125I (chloramine-T) and monospecific antibody was raised in rabbits. No appreciable cross-reactivity with apolipoproteins CI, CIII, AI, AII, low density lipoproteins, and lipoprotein-free plasma w
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7. Burkholderia (basonym Pseudomonas) cepacia binding to lipid receptors.
Piliated Burkholderia (formerly Pseudomonas) cepacia from sputa of cys tic fibrosis patients in Toronto, Canada, were shown earlier to bind to purified mucins and to a protein receptor on epithelial cells via a 22-kDa adhesin located on unique cable pili. However, a second receptor, thought to be lipid in nature, was also identified on cells and appeared to
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8. Binding of nonmucoid Pseudomonas aeruginosa to normal human intestinal mucin and respiratory mucin from patients with cystic fibrosis.
Lung infections due to Pseudomonas aeruginosa and Pseudomonas cepacia are common in patients with cystic fibrosis. Initial colonization is due to nonmucoid P. aeruginosa, while later mucoid variants emerge and are associated with chronic infection. P. cepacia colonization tends to be more prevalent in older patients. The present study was conducted to discov
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9. Hydroxyl radical scavengers inhibit lymphocyte mitogenesis.
Agents that are known to be scavengers of hydroxyl radicals inhibit lymphocyte mitogenesis induced by phorbol myristate acetate (PMA) to a greater extent than they inhibit mitogenesis induced by concanavalin A or phytohemagglutinin. These agents include dimethyl sulfoxide, benzoate, thiourea, dimethylurea, tetramethylurea, L-tryptophan, mannitol, and several
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10. Interactions between Campylobacter jejuni and lipids.
We previously showed that motility plays several key roles in Campylobacter jejuni pathogenesis, including increasing the efficiency of C. jejuni attachment to host epithelial cells. To further characterize C. jejuni attachment, we first examined the role of carbohydrates. Experiments with Chinese hamster ovary (CHO) cell mutants with defined defects in comp
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11. Metabolism of apoprotein B of plasma very low density lipoproteins in the rat.
As an extension of metabolic studies of the cholesteryl ester component of rat very low density lipoproteins, we have studied the metabolism of the B apoprotein component labeled by intravenous injection of [3H]lysine. The B apoprotein separated from other apoproteins by delipidation and selective precipitation with tetramethylurea could not be distinguished
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12. Apolipoprotein is responsible for neutralization of xenotropic type C virus by mouse serum
We have shown that the circulating lipoproteins of the mouse contain a potent inhibitor of infectivity of the xenotropic type C virus. This virus neutralization does not involve immunoglobulins or complement. After fractionation of the lipoproteins on the basis of particle size, flotation properties, and electrostatic charge, virus neutralizing activity is f