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Thermoluminescent Characteristics of Li2B4O7 Doped with Mn2+ and Eu3+ Ions
Analysis of thermoluminescent properties were made for two samples; Li2B4O7, Li2B4O7:Mn2+:Eu3+. These samples were prepared by melt quenching method. The glow curves of the samples show two broad peaks at 160º C and 245 ºC, and a high peak at 130ºC for Li2B4O7 doped. The response of the materials were analyzed according to the doses (0.2-80 Gy), fading (0-72 hours) and reproducibility of the experiment (10 times). To determine how the glow curve is formed, thermal bleaching for a dose of 5 Gy were made from room temperature to 300º C. Besides, X-ray diffraction patterns were recorded to identify the structure and grain size of the samples
EFICÁCIA DE COLOIDES VS CRISTALOIDES NA REPOSIÇÃO VOLÉMICA A NÍVEL HEPÁTICO EM PACIENTES HEMORRÁGICOS
Apesar dos avanços na sua abordagem terapêutica, a hemorragia severa continua a ser a principal causa de morbilidade e mortalidade em animais vítimas de trauma ou sujeitos a intervenção cirúrgica. A causa das lesões decorrentes, ou da morte consequente, deve-se ao deficit de volume de fluidos intravasculares e subsequente desenvolvimento do estado hipovolémico.O controlo da hipovolémia passa pela resolução da hemorragia e pela correção do deficit de volume intravascular causado e envolve, obrigatoriamente, o recurso à administração de fluidos intravenosos. A escolha do tipo de fluido mais adequado para a terapia intravenosa (IV), em cada ocorrência, é uma tarefa que exige reflexão e ponderação. O objetivo deste trabalho consistiu na avaliação do tipo de fluido mais adequado e eficiente para efetuar a reposição volémica em pacientes hemorrágicos, em particular no respeitante a qual deles acarreta menor comprometimento da função hepática. As lesões histopatológicas avaliadas nos diferentes grupos deste estudo não revelaram diferenças estatisticamente significativas entre os 3 grupos, o que validou a possibilidade de se usar qualquer um dos fluidos testados. Contudo, foi notória uma maior intensidade da gravidade das lesões no grupo 2. Assim, foi possível concluir que o uso do hidroxietilamido 130/0,4, em detrimento do lactato de Ringer em situações de hipovolémia, contribui para a preservação da integridade histológica e fisiológica hepática.COMPETE - FCOMP-01-0124-FEDER-009525; FCT/CI&DETS (PEst-
OE/CED/UI4016/2011
Milho com alto potencial produtivo e lucrativo.
bitstream/item/84224/1/Milho-alto-potencial.pd
The impact of silent vascular brain burden in cognitive impairment in Parkinson's disease
White matter hyperintensities (WMHs) detected by magnetic
resonance imaging (MRI) of the brain are associated with dementia and cognitive
impairment in the general population and in Alzheimer's disease. Their effect in
cognitive decline and dementia associated with Parkinson's disease (PD) is still
unclear. METHODS: We studied the relationship between WMHs and cognitive state in
111 patients with PD classified as cognitively normal (n = 39), with a mild
cognitive impairment (MCI) (n = 46) or dementia (n = 26), in a cross-sectional
and follow-up study. Cognitive state was evaluated with a comprehensive
neuropsychological battery, and WMHs were identified in FLAIR and T2-weighted
MRI. The burden of WMHs was rated using the Scheltens scale. RESULTS: No
differences in WMHs were found between the three groups in the cross-sectional
study. A negative correlation was observed between semantic fluency and the
subscore for WMHs in the frontal lobe. Of the 36 non-demented patients
re-evaluated after a mean follow-up of 30 months, three patients converted into
MCI and 5 into dementia. Progression of periventricular WMHs was associated with
an increased conversion to dementia. A marginal association between the increase
in total WMHs burden and worsening in the Mini Mental State Examination was
encountered. CONCLUSIONS: White matter hyperintensities do not influence the
cognitive status of patients with PD. Frontal WMHs have a negative impact on
semantic fluency. Brain vascular burden may have an effect on cognitive
impairment in patients with PD as WMHs increase overtime might increase the risk
of conversion to dementia. This finding needs further confirmation in larger
prospective studies
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