The changes that have occurred within medical science originated in the rapid developments that took place in the applied sciences(chemistry,physics,engineering,microbiology,physiology,pharmacology,etc.) at the turn of the century.This process of development was characterized by intense interdisciplinary cross-fertilization,which provided an environment in which medical research was able to take giant strides in developing techniques for the diagnosis and treatment of disease.For example,in 1903,Willem Einthoven,a Dutch physiologist,devised the first electrocardiograph to measure the electrical activity of the heart.In applying discoveries in the physical sciences to the analysis of the biologic process,he initiated a new age in both cardiovascular medicine and electrical measurement techniques.

New discoveries in medical sciences followed one another like intermediates in a chain reaction.However,the most significant innovation for clinical medicine was the development of x-rays.These "new kinds of rays,"as their discoverer W.K.Roentgen described them in 1895,opened the "inner man" to medical inspection.Initially,x-rays were used to diagnose bone fractures and dislocations,and in the process,x-ray machine(medical equipments) became commonplace in most urban hospitals.Separate departments of radiology were established,and their influence spread to other departments throughout the hospital.By the 1930s,x-ray visualization of practically all organ systems of the body had been made possible through the use of barium salts and a wide variety of radiopaque materials.

X-ray technology gave physicians a powerful tool that,for the first time,permitted accurate diagnosis of a wide variety of diseases and injuries.Moreover,since x ray machines for sale were too cumbersome and expensive for local doctors and clinics,they had to be placed in health care centers or hospitals.Once there,x-ray technology essentially triggered the transformation of the hospital from a passive receptacle for the sick to an active curative institution for all members of society.