Onset of dynamic activity in globally coupled excitable and oscillatory units.

The onset of dynamic activity is studied in heterogeneous populations of globally coupled units such that each unit is either excitable or oscillatory depending on its parameter. By varying the mean of the parameter distribution as well as coupling strength, we show that all or part of the populations studied have common features: similar phase diagrams, hysteresis near or at the onset of dynamic activity, and a fractional power law obeyed by an order parameter. A simplified model is proposed to explain these results.

[The effect of preoperative epidural morphine on postoperative pain].

Postoperative analgesia was assessed by examining nurses' records of 421 gynecological operative cases between January, 1989 and November, 1990. The criterion used in the analysis was the need for analgesics for pain within 24 hours postoperatively. After receiving morphine (2 mg, 4 mg, 5 mg, 6 mg) with local anesthetics or physiological saline solution into the epidural space (lower thoracic, lower lumbar, or both regions), the patient was intubated with thiopental, diazepam, and a muscle relaxant (vecuronium or pancuronium).

Safety of ablation of the sigmoid and transverse sinuses: an experimental study.

If the sigmoid and transverse sinuses could be divided safely, surgeons could broaden their access during skull base surgery without retracting the brain extensively. We undertook this study in monkeys to assess the risk of sacrificing these sinuses. We learned that when bilateral transverse sinuses were occluded, the sinus pressure measured in the superior sagittal sinus increased significantly as blood was purged from sinus venules.

[A successful treatment of spontaneous carotid cavernous fistula causing hemorrhagic infarction treated by detachable balloon].

A rare case of hemorrhagic infarction associated with carotid-cavernous fistula is reported. The patient was a 74-year-old female. CT scan showed hemorrhagic infarction of the left superior temporal gyrus, irregular vascular enhancement of the bilateral front-temporal lobe, and dilatation of the cavernous sinus.

[A simple method of extracorporeal membrane oxygenation (ECMO)--3. The effects of pumpless ECMO (arterio-venous shunt) on arterial blood gas measured for 24 hours].

In eight anesthetized mongrel dogs, the pumpless ECMO applied between the femoral artery and vein was performed under the condition of hypoventilation for 24 hours. The methods were same as the first and second reports, except the pumpless ECMO was used. The abnormal parameters in the cardiovascular and respiratory system (blood gas analysis and end expiratory gas analysis), induced by hypoventilation, recovered to almost normal ranges, by operation of the pumpless ECMO for 24 hours.