It is time to move from the nursing process to critical thinking

As we reflect on the concept of critical thinking in perioperative nursing practice, we should ask ourselves whether we think critically. If not, we must learn the principles of critical thinking and apply them in our clinical practice settings. Our perioperative nurse managers and directors must demonstrate critical thinking in leading other nurses in the delivery of quality, cost-effective, service-oriented patient care. They also must identify peers who use critical thinking skills to support and sustain them in their quest.     

Nalidixic acid and macromolecular metabolism in Tetrahymena pyriformis: effects on protein synthesis

A study on the effect of nalidixic acid on macromolecular metabolism, particularly of protein, in Tetrahymena pyriformis was performed. It was shown that the compound is a potent inhibitor of deoxyribonucleic acid, ribonucleic acid, and protein synthesis for this organism. A conspicuous breakdown of polysomes, accompanied by the accumulation of 80S ribosomes, occurred in cells incubated for 10 min with the drug; polysome formation was prevented. The accumulating 80S particles were shown to be run-off ribosomal units. The incorporation of amino acids by a cell-free system is not affected by nalidixic acid. In nonproliferating cells the incorporation was also not prevented, unless the cells were previously incubated with the drug. These results are discussed in terms of the possible mechanism of action of nalidixic acid in T. pyriformis.     

Distribution of HEOD (dieldrin) in mammals: III. Transport--transfer

A mathematical model simulating the blood transport and tissue residue distributions of the highly toxic and highly lipid soluble pesticide dieldrin in mammals is presented. This model is a significant improvement over our previously published preliminary model for dieldrin distribution in mammals. The assumptions and working hypotheses of the model are presented and used in generating a set of differential equations based upon mass balance principles. Two simulation cases are examined. The first simply demonstrates the gross features of: 1) Transport limiting conditions; 2) equal transport-equal membrane transfer conditions, and 3) membrane transfer limit conditions. The second studies a single tissue (the blood-brain barrier case) example of the above mentioned conditions. All simulations made were conducted for a hypothetical mature male rate of the average Wistar type eating food ad lib.     

Effect of EGb 761, a ginkgo biloba extract, on early arrhythmia induced by coronary occlusion and reperfusion in dogs

EGb 761 is a preparation of Ginkgo biloba extract, which has complex biologic actions including free radical scavenging activity. To examine the anti-arrhythmic effect of EGb 761, a canine preparation of coronary artery occlusion-reperfusion was tested. Under intravenous anesthesia and open chest conditions, 32 dogs were subjected to 30 min of coronary occlusion, followed by reperfusion. Twelve received EGb 761 by intravenous injection, 1 mg/kg five minutes before coronary occlusion, followed by a continuous infusion of 0.1 mg/kg/min until five minutes after reperfusion. Immediately prior to reperfusion, an additional bolus dose of EGb 761 (1 mg/kg) was again injected (group A). The remaining 20 dogs received saline injection, and served as the control (group B). The electrocardiographic changes were recorded during the whole experimental course. The results showed that, during coronary occlusion, group A dogs had a lower count of ventricular premature beats than group B dogs. However, there was no difference in the incidence of ventricular tachycardia (VT) between the two groups. The duration of VT of the treated dogs was similar to that of the control dogs. The incidence of ventricular fibrillation (VF) was also similar. Upon reperfusion, the treated dogs were shown to be protected from VF. The duration of VT was also shorter in the treated group, although the incidence of VT was not different between the two groups. EGb 761 is effective in preventing early VF induced by coronary reperfusion while ineffective in protecting the ischemic VT and VF.