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Biomedical subjects

M A Gouveia

Publications and source records attributed to M A Gouveia.

15 recordsLinked to original sources
PubMed1994

Intercomparison of techniques available at INETI in the analysis of two IAEA candidate research materials.

Under contract with the IAEA, the epiphytic lichen Evernia prunastri was collected to prepare a multielement lichen reference material for quality assurance of environmental studies. An intercomparison run on trace and minor elements in this candidate research material (IAEA-336) was organized in which six analytical groups of the National Institute of Engineering and Industrial Technology (INETI) took part. INAA, PIXE, XRF, AAS, and ICP-ES were applied. The results obtained by different methods are compared, and their complementarity is discussed. As a quality control, the IAEA cabbage research material (IAEA-359) was analyzed. The results agree quite well with the estimated values given by the IAEA.

Environmental Monitoring↗
PubMed1991

Factor for correcting the ruthenium interference in instrumental neutron activation analysis of barium in uraniferous samples.

The fission spectral interference of ruthenium on the instrumental neutron activation analysis of barium in samples containing uranium is extensively discussed. In particular the dependence of the correction factor on the phi epi/phi th ratio is studied. An excellent agreement between experimental and calculated values is achieved. A procedure is suggested for the resolution of multiple interferences in the general case where uranium, barium and/or ruthenium are present in samples to be analysed.

Barium↗
PubMed1987

The significance of female sex steroids on the vascular permeability of the traumatised uterine serosa of rats.

Using experiments with conjugated hormones, and their influence on vascular permeability assessed by the colloidal carbon technique, we have investigated the effect of female sex steroids on the microcirculation of the uterine horn of virgin rats. We found that oestrogen inhibited vascular permeability in inflammatory conditions. Progesterone increased vascular permeability.

Animals↗
PubMed1985

Influence of antigen charge in the pathogenicity of immune complexes in rats.

Immune complexes (IC) formed in the presence of excess antigen with native human anionic (AA) or cationic (CA) albumin and anti-human albumin rabbit gamma globulin were administered to 51 female Wistar rats. In animals injected with IC formed with CA, IC deposition in the renal glomeruli (glomerular capillary walls and mesangium) occurred as early as 5 min after injection. These animals also showed slight alterations in renal structure and albuminuria, whereas in the animals injected with IC formed with AA there was no IC deposition in the renal glomeruli nor any alteration in renal structure or albuminuria. The serum complement levels of animals injected with IC formed with CA were significantly lower than those observed in animals treated with similar doses of IC formed with AA. In vitro experiments also showed that the IC formed with CA fixed more complement than those formed with AA.

Albuminuria↗
PubMed1984

Effect of urinary alkalinization on renal changes produced by cationic albumin.

40-mg doses of human cationic (CA) or anionic (AA) albumin were administered intravenously to 48 normal female rats. Sodium bicarbonate (NaHCO3) was administered to 8 of these animals before CA or AA. Urine alkalinization caused increased renal CA excretion in CA-injected animals, which also showed marked reduction of the intensity of the renal changes produced by CA.

Albumins↗
PubMedDate not supplied

The testes in cadmium intoxication: morphological and vascular aspects.

Cadmium toxicity was tested on young male Wistar rats by injecting 1 mg/ml of cadmium chloride (CdCl2) intra-peritoneally. Post-mortem examination was done 4 hours, 24 hours and 14 days after cadmium administration to observe time-sequence cadmium-induced alterations in vascular permeability of the mesothelium in the pleura, peritoneum and tunica vaginals. This paper mainly reports the alterations observed in the testes. Vascular permeability was assessed by the colloidal carbon technique. Vascular labelling was evidenced as early as 4 hours after CdCl2, injection; 24 hours later severe oedema with leakage of particles to the interstitium and also into the tubules was patent. Fourteen days after CdCl2 administration atrophy of the testes with necrosis of the tubules, fibrosis of the interstitium and vascular thrombosis was found, compatible with chemical castration.

Animals↗