941 resultados para METAL-ION IMPLANTATION
Resumo:
The green alga Pseudokirchneriella subcapitata has been widely used in ecological risk assessment, usually based on the impact of the toxicants in the alga growth. However, the physiological causes that lead algal growth inhibition are not completely understood. This work aimed to evaluate the biochemical and structural modifications in P. subcapitata after exposure, for 72 h, to three nominal concentrations of Cd(II), Cr(VI), Cu(II) and Zn(II), corresponding approximately to 72 h-EC10 and 72 h-EC50 values and a high concentration (above 72 h-EC90 values). The incubation of algal cells with the highest concentration of Cd(II), Cr(VI) or Cu(II) resulted in a loss of membrane integrity of ~16, 38 and 55%, respectively. For all metals tested, an inhibition of esterase activity, in a dose-dependent manner, was observed. Reduction of chlorophyll a content, decrease of maximum quantum yield of photosystem II and modification of mitochondrial membrane potential was also verified. In conclusion, the exposure of P. subcapitata to metals resulted in a perturbation of the cell physiological status. Principal component analysis revealed that the impairment of esterase activity combined with the reduction of chlorophyll a content were related with the inhibition of growth caused by a prolonged exposure to the heavy metals.
Resumo:
Disserta ção apresentada para obten ção do Grau de Mestre em Engenharia Química e Bioquímica
Resumo:
Dissertação para obtenção do Grau de Doutor em Engenharia Química, especialidade de Engenharia Bioquímica
Resumo:
Dissertação para obtenção do Grau de Mestre em Engenharia Química e Bioquímica
Resumo:
J Biol Inorg Chem (2011) 16:51–61 DOI 10.1007/s00775-010-0700-8
Resumo:
J Biol Inorg Chem (2008) 13:1185–1195 DOI 10.1007/s00775-008-0414-3
Resumo:
J Biol Inorg Chem (2006) 11: 548–558 DOI 10.1007/s00775-006-0104-y
Resumo:
Dissertação para obtenção do Grau de Doutor em Engenharia Física
Resumo:
The classic transvenous implantation of a permanent pacemaker in a pectoral location may be precluded by obstruction of venous access through the superior vena cava or recent infection at the implant site. When these barriers to the procedure are bilateral and there are also contraindications or technical difficulties to performing a thoracotomy for an epicardial approach, the femoral vein, although rarely used, can be a viable alternative. We describe the case of a patient with occlusion of both subclavian veins and a high risk for mini-thoracotomy or videothoracoscopy, who underwent implantation of a permanent single-chamber pacemaker via the right femoral vein.
Resumo:
Dissertação para obtenção do Grau de Mestre em Arte e Ciência do Vidro
Resumo:
Dissertation presented to Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa for obtaining the master degree in Membrane Engineering
Resumo:
Dissertation to obtain a Master degree in Biotechnology
Resumo:
Dissertação para obtenção do Grau de Doutor em Química Sustentável
Resumo:
Dissertação para obtenção do Grau de Doutor em Engenharia Química
Resumo:
Dissertação para obtenção do Grau de Mestre em Engenharia Física