RESUMO
An optimized FT Raman microscope (inverted microscope with high throughput of radiation) was developed that allows minimal sample preparation and Raman spectroscopy without fluorescence. A quantitative determination of the mineralization of bone tissue and hydroxyapatite (HA) coatings of hip and knee prostheses was performed. The lateral resolution reached down to 10 microm. The distribution of the HA content in the coatings investigated was found to be similar all the time. This result was independent of the composition of the coatings and the history of the whole prosthesis. In the immediate vicinity of the prosthesis a large HA content could be observed that decreased to a minimum towards the periphery of the coating and increased at the site of the ongrown bone. For the interface between bone and HA coating a transitional zone was observed at a lateral distance of 30-40 microm to the implant.
Assuntos
Osso e Ossos/química , Durapatita/análise , Microscopia/métodos , Análise Espectral Raman/métodos , Animais , Osso e Ossos/metabolismo , Calcificação Fisiológica , Tecido Conjuntivo/metabolismo , Cães , Durapatita/metabolismo , Membro Posterior , Prótese de Quadril , Humanos , Prótese do Joelho , Fosfatos/análiseAssuntos
Benzofuranos/análise , Braquiúros/química , Nephropidae/química , Dibenzodioxinas Policloradas/análise , Poluentes Químicos da Água/análise , Animais , Peso Corporal/efeitos dos fármacos , Pesqueiros , Cromatografia Gasosa-Espectrometria de Massas , Fígado/química , Biologia Marinha , Músculos/química , New Jersey , New York , Pâncreas/químicaRESUMO
When tobacco (Nicotiana tabacum L. var. Virginia Gold) plants were pretreated with Na ((22)Na) several days before detopping, from 2.3 to 4.9% of Na previously accumulated in roots appeared in the xylem exudate in 7 days after detopping. Na from the external medium, however, was readily transported to the exudate. Moreover, the amount of the pretreatment Na that was transported to the exudate was not influenced by the presence of Na in the external medium. When Na was present in the external medium after detopping, about 4% (with an NaNO(3) post treatment) to 10% (with an NaCl post treatment) of the Na transported to the xylem in the 7 days following detopping originated in the vacuoles. Nitrate salts of K or Na in the external medium after detopping resulted in transport of large quantities of the respective cation to the exudate, but not in increased transport of the pretreatment Na. A much larger percentage of the K that was accumulated after detopping than of the Na similarly accumulated was transferred to the xylem exudate.
