Word: medulla
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Dates: during 1940-1949
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...electrophrenic respirator, which looks like a small horn radio, is designed to aid patients suffering from bulbar poliomyelitis. In this type of the disease, the phrenic nerve, running from the medulla to the breathing-control muscles of the diaphragm, is unharmed...
When circulation to the cortex is impeded, the blood bypasses the cortex and flows through bigger blood vessels in the kidney's medulla or interior (see cut). The cortex, starved for blood and oxygen, deteriorates. Results: 1) the production of urine slows or stops altogether; 2) the anemic cortex apparently secretes a substance (perhaps a hormone) that raises blood pressure throughout the body...
...certain hormones (e.g., adrenalin, pituitrin), and injections of the poison secreted by staphylococcus germs. All of these stimuli, the investigators decided, activate nerves which constrict the kidneys' blood vessels and divert the blood flow from the small vessels in the cortex to the larger ones in the medulla. Lack of blood in the cortex, in turn, raises blood pressure (an automatic adjustment of the body trying to force more blood intp the cortex...
...during the poliomyelitis season (summer and fall), even though the disease "is not notably prevalent in a community." Probable connection between tonsillectomies and poliomyelitis: nerves injured by surgery are more susceptible to polio infection, so that the latent virus could travel readily from the injured throat nerves to the medulla oblongata, where the spinal cord enters the brain...
...normal air, breathing is controlled by the respiratory centre in the medulla, which is part of the brain. But this centre is itself enfeebled by oxygen lack, passes control to secondary centres, the carotid bodies in the neck and the aortic body near the heart. Lack of oxygen stimulates instead of enfeebling these secondary centres, and they send out stronger and stronger impulses to the respiration muscles. If the lungs suddenly get more oxygen, the carotid and aortic bodies rest, turn back control to the centre in the medulla. But that stupefied centre may not be in shape to take...