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1.
Science ; 258(5089): 1742-7, 1992 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-17831654

RESUMO

Changes in the federal budget over the last several decades have raised current consumption at the expense of the investment needed for stronger economic growth. These changes have occurred in the budget's fiscal policy, which has reduced national saving and private investment; in its expenditure policy, which has emphasized short-term benefits rather than public investments; and in its transfer policy, which has not adequately addressed the increasing child poverty that threatens the productivity of our future labor force.

2.
Clin Nephrol ; 65(2): 138-40, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16509465

RESUMO

Hypertensive brain stem encephalopathy is a rare disorder that can be seen in severe hypertensive encephalopathy. Patients with chronic renal failure are more prone to develop this disorder because a mild elevation of the blood pressure can already induce brain changes. It is important to diagnose this entity as soon as possible because the symptoms and brain stem lesions are reversible following treatment and because it is important to exclude brain stem ischemia in the diagnostic work-up. Brain MRI and particularly diffusion weighted images are crucial for this purpose.


Assuntos
Tronco Encefálico/patologia , Encefalopatia Hipertensiva/etiologia , Falência Renal Crônica/complicações , Idoso , Diagnóstico Diferencial , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Encefalopatia Hipertensiva/diagnóstico
3.
J Agric Food Chem ; 47(5): 1794-800, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10552454

RESUMO

Thermal and pressure inactivation of myrosinase from broccoli was kinetically investigated. Thermal inactivation proceeded in the temperature range 30-60 degrees C. These results indicate that myrosinase is rather thermolabile, as compared to other food quality related enzymes such as polyphenol oxidase, lipoxygenase, pectinmethylesterase, and peroxidase. In addition, a consecutive step model was shown to be efficient in modeling the inactivation curves. Two possible inactivation mechanisms corresponding to the consecutive step model were postulated. Pressure inactivation at 20 degrees C occurred at pressures between 200 and 450 MPa. In addition to its thermal sensitivity, the enzyme likewise is rather pressure sensitive as compared to the above-mentioned food quality related enzymes. By analogy with thermal inactivation, a consecutive step model could adequately describe pressure inactivation curves. At 35 degrees C, pressure inactivation was studied in the range between 0. 1 and 450 MPa. Application of low pressure (<350 MPa) resulted in retardation of thermal inactivation, indicating an antagonistic or protective effect of low pressure.


Assuntos
Brassica/enzimologia , Glicosídeo Hidrolases/química , Estabilidade Enzimática , Glicosídeo Hidrolases/antagonistas & inibidores , Temperatura Alta , Cinética , Pressão , Termodinâmica
4.
J Agric Food Chem ; 47(6): 2404-9, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10794643

RESUMO

Degradation of chlorophyll in broccoli juice occurred at temperatures exceeding 60 degrees C. Chemical analysis revealed that degradation of chlorophyll a and b to pheophytin a and b, respectively, followed first-order kinetics and that chlorophyll a was more heat sensitive than chlorophyll b. Temperature dependencies of chlorophyll a and b degradation rate constants could be described by Arrhenius equations with activation energies (E(a)) of 71.04 +/- 4.89 and 67.11 +/- 6.82 kJ/mol, respectively. Objective greenness measurements, using the -a value as the physical property, together with a fractional conversion kinetic analysis, indicated that green color degradation followed a two-step process. Kinetic parameters for the first degradation step were in accordance with the kinetic parameters for pheophytinization of the total chlorophyll content, as determined by chemical analysis (E(a) approximately 69 kJ/mol). The second degradation step, that is, the subsequent decomposition of pheophytins, was characterized by an activation energy of 105.49 +/- 4.74 kJ/mol.


Assuntos
Bebidas/análise , Brassica/química , Clorofila/química , Clorofila A , Cor , Temperatura Alta , Cinética
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