PubMed Health⌕ Search

Biomedical subjects

E Christoffersen

Publications and source records attributed to E Christoffersen.

3 recordsLinked to original sources

Adsorption-induced step formation.

Through an interplay between density functional calculations, Monte Carlo simulations and scanning tunneling microscopy experiments, we show that an intermediate coverage of CO on the Pt(110) surface gives rise to a new rough equilibrium structure with more than 50% step atoms. CO is shown to bind so strongly to low-coordinated Pt atoms that it can break Pt-Pt bonds and spontaneously form steps on the surface. It is argued that adsorption-induced step formation may be a general effect, in particular at high gas pressures and temperatures.

Journal Article↗

Assessment of verapamil in the treatment of angina pectoris.

A brief review is given of the pharmacological data of verapamil, which chemically shows a certain similarity to papaverine. The effect of the drug (80 mg) 3 times daily, on angina pectoris, as compared with placebo, was evaluated in a double-blind cross-over therapeutic trial with 4-wk periods in 47 patients. The incidence of attacks and the nitroglycerine consumption decreased in the second fortnight of the verapamil period by approximately 25% compared with the placebo period. An ergometer test showed a prolongation of the exerice time of 20%. The mean blood pressure and the heart rate fell under verapamil treatment if the patients had values which were relatively high in the placebo period. The increase in heart rate during exercise from two different resting levels showed a tendency to become more pronounced under treatment with verapamil than under placebo. The length of the P-Q intervals were not affected by verapamil. The mechanism of action in angina pectoris is discussed, but it is concluded that it is still not possible to explain it. Twelve Danish medical departments took part in the trial.

Aged↗