Teste Repositóri
2014-01-01
Resultados de pesquisa
Foram encontrados 47 registos.
Problems related to the left ventricular outflow tract are not always amenable to conventional surgical methods, and in some cases may be solved with the creation of a double outlet left ventricle, using a composite rigid pyrolite left ventricular apex outlet prosthesis and a fabric valve-containing conduit. The primary indication for apico-aortic conduits is severe left ventricular outlet obstruction that is not correctable by conventional surgical techniques. Failure to relieve ventricular hypertension causes persistent physiologic derangements that include increased left ventricular work and oxygen consumption. decreased cardiac output, and compromise of coronary perfusion. Our clinical experience in excess of 18 months with valved apicoaortic conduits for primary or recurrent left ventricular outflow tract obstructions has been pro...
Studies testing the ‘‘immunocompetence
handicap hypothesis’’ have focussed on the immunosuppressive
effects of androgens. Several recent studies have
reported that mounting a humoral immune response might
also result in a decrease in circulating androgen levels via
a ‘‘negative feedback’’ on the hypothalamus–pituitary–
gonadal axis (HPG). The aim of this correlative study was
to analyse these immunosuppressive and HPG-suppressive
interactions in reproductively active males of the peafowl.
We collected blood samples of free living birds before and
after challenging the immune system with a non-pathogenic
antigen (sheep erythrocytes), and analysed immune
parameters and plasma levels of the two main androgens in
birds, testosterone and dihydrotestosterone. Males displaying
larger versions of the main secondary sexual trait,
...
