Protein separations on tentacle ion exchangers

This study was undertaken to introduce new tentacle ion exchange materials to the biochromatographer. The differences in the bioseparation media have been shown with a four-component protein mixture. By controlling the sample loading and the flow rate, each material can be made to perform satisfactorily, according to the demands of the biochromatographer, whether for high resolution or high sample capacity. The controlled manufacturing techniques of the Fractogel and LiChrospher DEAE materials make any analytical or process separations equivalent and reproducible. When even higher capacities are required, the biochromatographer need only use the wider diameter Superformance glass columns packed with the equivalent Fractogel.

[Prognosis of chronic non-dystrophic and surgically treated aortic insufficiency]

Between January 1972 and March 1983, 123 patients with isolated non dystrophic aortic insufficiency underwent aortic valve replacement. During a mean follow-up period of 4.3 years per patient, 25.6 p. 100 of the patients died, including a 4.1 p. 100 hospital death rate. The actuarial survival rate was 74 p. 100 at 5 years and 62 p. 100 at 10 years. The main causes of mortality were heart failure, dysrhythmias and sudden death. A study of prognostic factors based on the preoperative data showed that clinical, radiological, electrocardiographic and haemodynamic signs were informative. In agreement with other authors, we found that preoperative cardiac dilatation and left ventricular dysfunction were predictive of a poor prognosis.