PubMed Health⌕ Search

Biomedical subjects

E F Crocker

Publications and source records attributed to E F Crocker.

27 records · Page 2Linked to original sources

Grey scale ultrasonic examination of the thyroid gland.

High resolution grey scale echography is an accurate, non-invasive means of investigating thyroid lesions. The structural information which it provides complements that of the functional status of the gland obtained from radionuclide scanning. The principles and practice of the technique are discussed and clinical examples are presented.

Adenoma↗

The effect of steroids on the extravascular distribution of radiographic contrast material and technetium pertechnetate in brain tumors as determined by computed tomography.

The effect of dexamethasone on the accumulation of iothalamate and 99mTc pertechnetate in cerebral tumors was investigated in 6 patients over a five-month period. Patients were examined by x-ray (transmission) computed tomography (CT) and by radionuclide (emission) computed tomography (RCT) prior to and during a course of dexamethasone therapy. Stenosis diminished the degree of accumulation of both agents but did not change the boundaries of their distribution.

Adult↗

Effects of hyperventilation on the circulatory response of the rabbit to arterial hypoxia.

1. The circulatory effects of artificial hyperventilation with air and low oxygen mixtures were studied in rabbits anaesthetized with chloralose-urethane and given decamethonium iodide. The role of vagal afferents in the response to hypoxia was also assessed in spontaneously breathing unanaesthetized and anaesthetized animals.2. In the anaesthetized rabbit artificial hyperventilation inhibited all the changes in autonomic activity to the heart and peripheral circulation resulting from stimulation of the arterial chemoreceptors, and also reduced vagal efferent tone. In animals with section of the carotid sinus and aortic nerves the changes in autonomic activity observed during hypoxia and hyperventilation were much smaller than in normal animals and affected only cardiac autonomic activity.3. The effects of hyperventilation during hypoxia were mediated chiefly through vagal afferents rather than through the effects of hypocapnia. In the absence of changes in autonomic activity (e.g. during artificial hyperventilation with air) the circulatory effects were small and less clearly related to afferent vagal activity.4. In the spontaneously breathing anaesthetized and unanaesthetized rabbit vagal afferent activity resulting from the respiratory response to hypoxia inhibits sympatho-adrenal activity in the same way as during hypoxia with artificial hyperventilation.5. The importance of the vagal afferent input in the rabbit is discussed in relation to the qualitative differences in circulatory response with increasing severity of hypoxia, and in relation to the effects of anaesthesia.

Anesthesia, Intravenous↗