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C G Moreira

Publications and source records attributed to C G Moreira.

5 recordsLinked to original sources
PubMed2000

Invasive medullary thymoma associated with Myasthenia gravis: an unusual case.

Thymomas are tumors characterized by a remarkable morphological heterogeneity and variable clinical behavior. This tumor has unique clinical associations, most notably with hematological abnormalities and myasthenia gravis. According with the Müller-Hermelink criteria, there are significant differences between the histological types of thymomas and the association with myasthenia gravis. Among the different histological types, medullary thymoma is the least frequent variant associated with this autoimmune disease. In this report we describe a case of medullary thymoma presenting in a 71-year- old woman with a myasthenic syndrome.

Aged↗
PubMed1997

[Gorlin's syndrome].

The major features of the nevoid basal-cell carcinoma syndrome are epidermal multiple cell carcinomas, cysts of the jaws and skeletal abnormalities, mainly in the ribs. The authors have reviewed the literature concerning multiple anomalies which are associated to this syndrome, and report a clinical case, emphasizing the advantages of early diagnosis, mainly for dermal and maxillary lesions.

Adolescent↗
PubMed1977

The inotropic memory of amphibian myocardium.

(1) Experimentally observed changes of contractile force induced by changes in the pattern of stimulation of frog ventricular myocardium were compared with predictions computed on the basis of a model for the contractile conditioning, proposed in a previous paper. (2) For this purpose, two functions (Potentiation and Inhibition) which describe in the model the effect of previous contractions, were determined experimentally. (3) It is shown that the model adequately predicts : force-frequency curve Inotropic Effect Curves at different basal frequencies, effect of the suppression of a contraction in a sequence of definite frequency, frequency-staircases, and strength-interval curves. (4) The formal characteristics of the model are discussed, and it is suggested that the potentiation mechanism results from the recirculation of activator calcium in two types of compartments, from which calcium passes to the myofilaments during the contractions or is lost to the exterior with first order kinetics during the rest period. Possible locations for these compartments are proposed. Various hypothesis on the nature of the inhibitory mechanism are considered.

Animals↗
PubMed1975

The inotropic memory of amphibian myocardium. I.-Identification of two stimultaneous mechanisms and statement of a model.

(1) The effects of previous contractions on the actual contractile strength is studied in strips of toad ventricle. The inotropic effect is quantified by superposing a conditioning contraction to a rhythm of definite frequency, its measure being the difference in strength between a rhythm contraction in the presence and in the absence of the conditioning one. (2) The inotropic effect is studied as a function of the interval between the actual and conditioning contractions. Depressed sections of the curve, associated to shortened action potentials, are detected and excluded. (3) The inotropic effect is always positive at low frequencies, but at higher frequencies and long intervals it becomes negative. (4)In high calcium concentration the inotropic effect is always negative and does not depend on frequency. Morever, the joint effect of two previous contractions is equal to the sum of the individual effects of each one. (5) The results are interpreted in terms of two independent elementary processes, one of which potentiates whereaas the other inhibits the strength of contraction. The former disappears in high calcium. Assuming some simple properties for these processes a mathematical expression has been achieved. This expression describes the inotropic effect of any sequence of contractions as a function of intervals involved.

Action Potentials↗