The advertising of doctors' services.

Medicine is unique among professions and trades, offering a 'product' which is unlike any other. The consequences for patients of being attracted by misleading information to an inappropriate doctor or service are such as to demand special restrictions on the advertising of doctors' services. Furthermore, health care in the UK is organised around the 'referral system', whereby general practitioners refer patients to specialists when necessary rather than have specialists accept patients on self-referral. But this need not inhibit the provision of helpful factual information to those who need it. Recent policy changes by the General Medical Council considerably broaden the scope for general practitioners to make factual information of their services available to local people, while safeguarding the public against promotional activities which are designed to increase demand for certain kinds of specialist service by playing upon individuals' fears and lack of medical knowledge.

Network regulation of the immune response: alternative control points for suppressor modulation of effector lymphocytes.

The network theory of the immune response proposed by Jerne has stimulated considerable interest, and a large body of evidence supporting this theory has been produced. However, the structure and function of the immune network have not been precisely defined. In this paper we develop several criteria to compare alternative systems on the basis of function and then examine mathematically the functional significance of two interactions involving suppressor regulation of effector lymphocytes in normal immune responses. The interactions examined in detail are suppressor regulation of the production of effector lymphocytes and suppressor regulation of the clearance of effector lymphocytes. The approach is one that has been used previously to predict and characterize function and design in biochemical and genetic control systems. The results of our analysis suggest that an immune system with suppressor regulation of the production of effector lymphocytes is equal or superior to a system without this form of regulation on the basis of all of the criteria examined in this study. Also, a system with regulation of the clearance of effector lymphocytes can be equal or superior to a system without this form of regulation on the basis of six criteria, but it is inferior to such a system on the basis of one criterion. Furthermore, a system with regulation of both production and clearance of effector lymphocytes is equal or superior to a system without regulation of production on the basis of all of the criteria and can be equal or superior to a system without regulation of clearance on the basis of six criteria, but it is inferior to such a system on the basis of one criterion. Similar conclusions hold for the comparison of systems in which regulation is exerted upon the production or clearance of effector molecules, such as antibodies or free radicals.

Network regulation of the immune response: modulation of suppressor lymphocytes by alternative signals including contrasuppression.

In the preceding paper we demonstrated that comparison of alternative designs for the immune network can be used to examine the functional significance of specified interactions in normal immune responses. In this paper we examine mathematically the functional significance of three interactions affecting the production of suppressor lymphocytes involved in regulation of normal immune responses. The interactions examined in detail are 1) antigenic stimulation of the production of suppressor lymphocytes, 2) idiotypic stimulation of the production of suppressor lymphocytes, and 3) antigenic inhibition of the production of suppressor lymphocytes (i.e., contrasuppression). The results of our analysis suggest that an immune system with only antigenic stimulation of suppressor production is less effective than a system with both antigenic and idiotypic stimulation of suppressor production on the basis of all of the criteria examined in this study. In turn, the latter system is less effective than a system with only idiotypic stimulation of suppressor production. Furthermore, a system with both idiotypic stimulation and antigenic inhibition of suppressor production can be equal or superior to a system with only idiotypic stimulation of suppressor production on the basis of the same criteria. Similar conclusions hold for the comparison of systems in which regulation by the suppressor lymphocytes of interest is exerted upon production of effector molecules rather than upon production of effector lymphocytes, and also for the comparison of systems in which interactions affecting the production of suppressor factors are of interest.

The doctor's dilemma.

The close relationship between expenditure on health care and the countless individual judgements made by doctors for their patients means that any discussion about rationing must involve the process of clinical decision-making. Increasingly, doctors are being drawn into rationing by two powerful forces. Firstly, through the corporate responsibilities of those working within a managed health care system in which organisational objectives and budgetary constraints are agreed and specified in a much more explicit way than ever before. Secondly, by the professionally-led movement towards more clinically effective practice. These, in combination, are leading towards a fundamental review of the nature and ethical basis of clinical practice in which the duty of doctors to individual patients must be balanced against the wider considerations.