RESUMO
Thirty-six patients with ruptured membranes and absent or infrequent uterine contractions underwent breast stimulation. The intensity and frequency of contractions were measured by an intrauterine pressure catheter. Unilateral breast stimulation produced uterine contractions with an average intensity of 48 mmHg and frequency of 3.6 minutes. In patients with previously infrequent contractions, unilateral breast stimulation significantly increased the frequency of contractions without changing the intensity. During breast stimulation, half of the patients experienced tachysystole (ie, contractions more frequently than two minutes apart), and five of 36 had prolonged contractions (ie, lasting more than 90 seconds). However, tachysystole and prolonged contractions rarely produced fetal heart rate decelerations.
Assuntos
Mama/fisiologia , Contração Uterina , Cateterismo/instrumentação , Feminino , Ruptura Prematura de Membranas Fetais/fisiopatologia , Frequência Cardíaca Fetal , Humanos , Estimulação Física , Gravidez , Estudos Prospectivos , Fatores de Tempo , Transdutores de PressãoRESUMO
Adaptation to ozone in respiratory tract mucociliary clearance was investigated in this study. Eighty rats inhaled insoluble radioactively labeled particles in order to permit monitoring of clearance. The respiratory tract and the feces were counted for radioactivity at fixed intervals to determine clearance rates. A brief challenge to 1.2 ppm of ozone following particle deposition caused a substantial delay in rapid (mucociliary) clearance. This delay (or "ozone effect") however, was eliminated by brief pre-exposure to 0.8 ppm of ozone 3 days prior to deposition of particles. When a 13-day period intervened between the ozone pre-exposure and challenge, a substantial delay (or "ozone effect") was again seen. Thus, the pre-exposure to ozone appeared to afford essentially complete protection at 3 days, and no protection by 13 days.