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971.
972.
Spleen and portal lymphnode sections from 86 drug addicts submitted for medico-legal autopsy at the Institute of Forensic Medicine in Copenhagen in the year 1979 were studied together with tissue sections from 24 "normal" persons. In 70% of the drug addicts the spleen weight was more than 200 g, and in 71% portal lymphnode hyperplasia was found. Birefringent foreign material was found in spleen tissue of drug addicts in 72% and in portal lymphnode tissue in 44%. Signs of antigen stimulation in both spleen and portal lymphnode tissue evaluated by the number of germinal centre and plasma cells were found in more than 80% of the drug addicts compared with about 20% of the "normal" persons. The results were related to anamnestic information of duration of drug abuse, to the spleen weight, to the occurrence of birefringent material and to the liver changes. Examination of lysozyme and immunoglobulin containing cells using the indirect preoxidase technique was performed in a total of 72 cases of spleen tissue, 59 cases of portal lymphnode tissue from drug addicts, 24 cases of spleen tissue and 18 of portal lymphnode tissue from "normal" persons. Lysozyme, IgM and IgG containing cells were found significantly more often among drug addicts than "normal" persons. The results indicate that the splenomegalia and the portal lymphnode hyperplasia often found in drug addicts are caused by continuous antigen stimulation due to repeated injections of various antigens.  相似文献   
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977.
The attention paid by the social work profession to ethical issues has waxed and waned since the formal inauguration of the profession in the late 19th century. For the first half century of the profession's life, relatively little attention was devoted to problems of professional ethics, though social work's literature was filled with discussions of value-laden issues that arise in practice. In recent years, interest in professional ethics has increased substantially. This article discusses the growth of interest in professional ethics, the formulation of the social work code of ethics, the adjudication of grievances in social work, and the strengths and limitations of the profession's code.  相似文献   
978.
Health care financing has undergone numerous structural changes over the years. Change continues while extreme growth seriously affects the health care focus. The author examines the multiclass system and health financing trends. Restructuring techniques are also discussed.  相似文献   
979.
The traditional separation of health care delivery and financing systems is breaking down as various new types of health care facilities are established and as payment continues to be a major concern. Group Health Cooperative of Puget Sound (GHC) was organized as a prepaid group practice system responsive to consumers. Costs, methods of payment and delivery of care are interrelated and are all influenced by consumer ownership. GHC has been refining its benefit programs since 1945. Strategies for controlling use and costs focus on improved provider management and on flexibility. This article explains how the structure of GHC benefits the consumer.  相似文献   
980.
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