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In this paper, thermodynamic considerations are applied to two biological processes, phagocytosis and platelet adhesion, the latter being an important step in thrombosis formation. Simple thermodynamic models in terms of changes of the Helmholtz free energy are presented for the engulfment of bacteria by phagocystic cells, as well as for the attachment of platelets to biomaterial surfaces. The interfacial tensions contained in the expressions for the Helmholtz free energy may be obtained from contact angles, by means of an equation of state approach. The in vitro phagocytosis tests show that hydrophobic bacteria are more readily phagocytized than hydrophilic ones, and the thermodynamic model elucidates the reason for this pattern of behaviour. Preliminary results for two types of platelet adhesion tests are presented. Although there is, in terms of simple thermodynamic considerations, a strong similarity between platelet adhesion and the early stages of phagocytosis, we anticipate that specific interactions will play a larger role in platelet adhesion than in phagocytosis.

This survey covers the use of statistical methods in three areas of medicine: (1) the obligatory instruction of students in statistics, (2) the statistical consulting of clinicians and their candidates for a doctor's degree and (3) the modification and creation of statistical methods by the statisticians in the departments of medical statistics and documentation. Moreover some factors are discussed that reduce the effectiveness of statistical consulting, may it be service, advisory work or collaboration. Other sections of this paper cover the calamity of utilization and evaluation of old clinical records, the avoidance of fallacies and of errors committed by the inappropriate and incorrect application of statistical methods in medicine. Supplementary questions are given as a "first help" in tackling problems in medicine.

This paper reports on a method which allows the separation of proteins of non concentrated CSF by means of the microzone technic. Pherograms of high quality were possible when the CSF contained more than 10 mg/dl total protein. Protein separation is completed in 16 min when one cellulose acetate strip with 150 V and 2 mA or when 150 V and 4 mA with two strips are used. Proteins were stained with nigrosine. The theoretical basis, technical details and error range of this method of protein separation are discussed.

In five volunteers fibrinolytic activity has been measured five times over a period of six weeks during increasing values of circadian rhythm. Euglobulinlysis-time, paper fibrinolysis, fibrinogen, plasminogen, alpha1-antitrypsin, alpha2-makroglobulin, thrombino-coagulase-time and fibrin-split-products were used in one study. An increase of fibrinolytic activity in the mooning was observed in all volunteers. Intraindividual variation of values is considerable but less than variation of values compared interindividually. Moreover variation was smaller at noon than in the time before noon. In clinical trial of the short-time effect of drugs the period of the plateau of the fibrinolytic activity should be used because of its smaller variation of values. Furthermore, in this period the intraindividual variation of the fibrinolytic activity is smaller than during increasing slope of the circadian rhythm of fibrinolysis. Intraindividual control should be granted.