Penicillin 青霉素.ppt

* A medical milestone -- Penicillin Penicillin The discovery, development and subsequent use of penicillin can be considered to be one of the most important breakthroughs in medical history. Penicillin has the ability to kill the disease-causing bacteria without being toxic to healthy cells. Antibiotics are natural substances that are released by bacteria and fungi into the their environment, as a means of inhibiting other organisms The discovery of Penicillin Alexander Fleming discovered the first antibiotic penicillin in 1928 by accident. In 1928, Fleming observed that the bacterium Staphylococcus aureus could be destroyed by the mold Penicillium notatum, proving that there was an antibacterial agent there in principle. This principle later lead to medicines that could kill certain types of disease-causing bacteria inside the body. Penicillin saved millions of lives The discovery of penicillin has often been described as a miracle drug. Prior to the discovery of penicillin, death could occur in very trivial injuries and diseases. It could occur from minor wounds that became infected, or diseases such as Strep Throat, and venereal diseases such as syphilis and gonorrhea. By the end of the World War II, enough penicillin was produced to treat seven million patients/year. (During WWI, death rate from pneumonia in the American Army totaled 18%. In WWII, it fell to less than 1%.) Penicillin-- the milestone in the history of antibiotics The discovery of penicillin makes people find a strong medicine to fight disease-causing bacteria, it ended the era of no treatment for infections and rose the climax to research new antibiotics. People entered a period to compound new drug. A number of previously incurable diseases were eradicated. Penicillin developed new antibiotics Since the mid-1940s, a number of new classes of antibiotics were developed. In 1945, Bejamin Duggar discovered aureomycin. Discoveries of new an