1. The soluble phospholipase D of cabbage was purified by heat treatment, acetone precipitation and electrophoresis on a density gradient of aqueous glycerol. 2. The purified enzyme slowly attacked a lecithin suspension whereas ultrasonically treated lecithin was hydrolysed more rapidly. 3. Diethyl ether stimulated the hydrolysis of both the lecithin suspension and ultrasonically treated lecith...

Ultrasonically-enhanced mass transport was exploited to increase preconcentration efficiency in anodic stripping voltammetry. We developed a Nafion-coated mercury thin-film working electrode which is stable under ultrasonic irradiation, making it possible to achieve very low limits of detection for relatively short preconcentration times. This allows the investigation of a variety of biological...

Gassy and degassed aqueous solutions of DNA were treated ultrasonically while monitoring the field for discrate cavitation events. At irradiation intensities greater than about 500 W/cm 2, transient cavitation is shown to be responsible forthe observed reduction i molecular weight. At intensifies of200 to 288 W/cm 2, degradation of DNA was observed which did not depend upon transient cavitation.

The relevant investigations and management of a case of alpha-thalassaemia major suspected antenatally is discussed. The value of ultrasonically guided cordocentesis in the definite diagnosis of this condition is emphasised in the management of this pregnancy. We believe that this is the first time such a procedure has been done in this country.