Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Health is the greatest gift of life. To watch out one's health means to avoid health problems; sufferings. However, there are many victims who suffer from diabetes, heart failures, cancer among other health problems. Fortunately, experts have discovered a new way for treating people - the replacing of some cells by other human cells from the body itself. The process allows medical researchers to alter some human cells into heart muscle cells for instance...