The dopamine transfer deficit model of attention deficit hyperactivity disorder (ADHD) is compared and contrasted with the existing dynamic developmental theory and the extended temporal difference (TD) model. The first two both identify learning deficits as a key problem in ADHD, but this mechanism would seem at least as likely to cause other…

Hormonal and metabolic changes, an essential part of the body's response to endurance exercise, are described. (Author/MT)

Discusses the physiology and biochemistry of the vitamin D endocrine system, including role of biological calcium and phosphorus, vitamin D metabolism, and related diseases. A 10-item, multiple-choice test which can be used to obtain continuing medical education credit is included. (JN)

Describes 16 mutagens/carcinogens found in plant food and coffee as well as several anticarcinogens also found in such food. Speculates on relevant biochemical mechanisms, particularly the role of oxygen radicals and their inhibitors in the fat/cancer relationship, promotion, anticarcinogenesis, and aging. (JN)

Reviews current findings that explain RNA's function as an enzyme in addition to being an informational molecule. Highlights recent research efforts and notes changes in the information base on RNA activity. Includes models and diagrams of RNA activity. (ML)

Cytoplasmic proteins form a highly structured yet changeable matrix that affects cell shape, division, motion, and transport of vesicles and organelles. Types of microfilaments, research techniques, actin and myosin, tumor cells, and other topics are addressed. Evidence indicates that the cell matrix might have a bearing on metabolism. (DH)

Discusses the chemical nature of gallstones and theories related to their formation. Also discusses experimental procedures used to identify chemical constituents of gallstones, indicating that cholesterol is found in almost 75 percent of stones examined. (JN)

This syllabus reviews information concerning calcium and phosphate regulation. Topics of interest include the following: calcium metabolism, phosphorus metabolism, bone, parathyroid hormone, calcitonin, and vitamin D. (CS)

Provides background information for teachers on the nature and role of sulfur in the biological and physical environments. Problems of sulfur in the air and in rain water are also considered. (JN)

New research suggests that personalities prone to extreme violence can be predicted by analysis of chemical elements found in human hair. Methodology employed and results obtained are highlighted and discussed. Relationships between diet and human behavior are also discussed. (JN)