文档介绍：Section I. Basic Principles
Chapter 1. Introduction
Definitions
Pharmacology can be defined as the study of substances that interact with living systems through
chemical processes, especially by binding to regulatory molecules and activating or inhibiting
normal body processes. These substances may be chemicals administered to achieve a beneficial
therapeutic effect on some process within the patient or for their toxic effects on regulatory
processes in parasites infecting the patient. Such deliberate therapeutic applications may be
considered the proper role of medical pharmacology, which is often defined as the science of
substances used to prevent, diagnose, and treat disease. Toxicology is that branch of pharmacology
which deals with the undesirable effects of chemicals on living systems, from individual cells to
complex ecosystems.
History of Pharmacology
Prehistoric people undoubtedly recognized the beneficial or toxic effects of many plant and animal
materials. The earliest written records from China and from Egypt list remedies of many types,
including a few still recognized today as useful drugs. Most, however, were worthless or actually
harmful. In the 2500 years or so preceding the modern era there were sporadic attempts to introduce
rational methods into medicine, but none were essful owing to the dominance of systems of
thought that purported to explain all of biology and disease without the need for experimentation
and observation. These schools promulgated bizarre notions such as the idea that disease was
caused by excesses of bile or blood in the body, that wounds could be healed by applying a salve to
the weapon that caused the wound, and so on.
Around the end of the 17th century, reliance on observation and experimentation began to replace
theorizing in medicine, following the example of the physical sciences. As the value of these
methods in the study of disease became clear, physicians in Great B