Monitoring the cardiovascular system

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Natural history and clinical significance of arrhythmias after acute cardiac infarction

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Effect of atropine on bradycardia and hypotension in acute myocardial infarction

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The inhibition of enzymes by beryllium

1. The action of beryllium on the following enzymes has been examined: alkaline phosphatase (Escherichia coli and kidney), acid phosphatase, phosphoprotein phosphatase, apyrase (potato), adenosine triphosphatase (liver nuclei, liver mitochondria, brain microsomes), glucose 6-phosphatase, polysaccharide phosphorylases a and b, phosphoglucomutase, hexokinase, phosphoglyceromutase, ribonuclease, A-esterase (rabbit serum), cholinesterase (horse serum), chymotrypsin. Alkaline phosphatase and phosphoglucomutase are inhibited by 1mum-beryllium sulphate whereas the other enzymes are largely unaffected by 1mm-beryllium sulphate. 2. Possible mechanisms for the inhibition of phosphoglucomutase and alkaline phosphatase are discussed.

The inhibition of phosphoglucomutase by beryllium

1. The inhibition of phosphoglucomutase by beryllium has been examined. 2. Inhibition by beryllium does not occur unless a complex-forming agent such as cysteine or imidazole is present. It is therefore similar to activation by magnesium. 3. The inhibition is progressive and the rate follows first-order kinetics, which may be defined by a bimolecular rate constant. 4. In the presence of magnesium the rate of inhibition is less. By using a fixed time for inhibition competition between beryllium and magnesium may be demonstrated. After inhibition has taken place, the addition of magnesium does not reverse it.

Haemodynamic effects of morphine in patients with acute myocardial infarction

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Growth-promoting and luteotrophic activities of human growth hormone

Human growth hormone prepared by Raben's (1959) method was chromatographed on various ion exchangers and the resulting fractions were assayed for growth-promoting, luteotrophic and immunological activity. A critical quantitative study of the biological activities of the fractions showed that there were significant differences between their ratios of growth-promoting to luteotrophic potency. The luteotrophic activity of some of the preparations was slightly higher than that of the 2nd International Ovine Prolactin Standard.