Cerebral hemodynamic crisis. Physiology, pathophysiology, and approach to therapy.

The physiology and pathophysiology of the cerebral circulation have been discussed in relation to treatment of the cerebral hemodynamic crisis. Data are presented to show how cerebral vascular resistance, the intracranial compartments, and brain metabolic demand may be manipulated to effect internal decompression and raise local perfusion pressures. It is quite apparent that irreversibility occurs rapidly in cases of complete ischemia and therapeutic success is often limited by this fact.

Plasma LH levels in the mare during the oestrous cycle.

Plasma levels of LH were determined by heterologous radioimmunoassay utilizing highly purified equine LH as standard. Samples were taken regularly from eleven mares for twenty-six oestrous cycles over a period of 10 weeks. The mean cycle length was 20-5 +/- 3-1 (S.