Technology Essay Research Paper Introduction Technology What — страница 3

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keep track of personnel and supplies. Medical Drugs: The use of immunization to prevent disease predated the knowledge of both infection and immunology. In China in approximately 600 BC, smallpox material was inoculated through the nostrils. Inoculation of healthy people with a tiny amount of material from smallpox sores was first attempted in England in 1718 and later in America. Those who survived the inoculation became immune to smallpox. American statesman Thomas Jefferson traveled from his home in Virginia to Philadelphia, Pennsylvania to undergo this risky procedure. A significant breakthrough came in 1796 when British physician Edward Jenner discovered that he could immunize patients against smallpox by inoculating them with material from cowpox sores. Cowpox is a far

milder disease that, unlike smallpox, carries little risk of death or disfigurement. Jenner inserted matter from cowpox sores into cuts he made on the arm of a healthy eight- year-old boy. The boy caught cowpox. However, when Jenner exposed the boy to smallpox eight weeks later, the child did not contract the disease. The vaccination with cowpox had made him immune to the smallpox virus. Today we know that the cowpox virus antigens are so similar to those of the smallpox virus that they trigger the body’s defenses against both diseases. In 1885, Louis Pasteur created the first successful vaccine against rabies for a young boy who had been bitten 14 times by a rabid dog. Over the course of ten days, Pasteur injected progressively more virulent rabies organisms into the boy,

causing the boy to develop immunity in time to avert death from this disease. Another major milestone in the use of vaccination to prevent disease occurred with the efforts of two American physician-researchers. In 1954 Jonas Salk introduced an injectable vaccine containing an inactivated virus to counter the epidemic of poliomyelitis. Subsequently, Albert Sabin made great strides in the fight against this paralyzing disease by developing an oral vaccine containing a live weakened virus. Since the introduction of the Sabin vaccine in 1961, polio has been nearly eliminated in many parts of the world. As more vaccines are developed, a new generation of combined vaccines are becoming available that will allow physicians to administer a single shot for multiple diseases. Work is also

under way to develop additional orally administered vaccines and vaccines for sexually transmitted diseases. Possible future vaccines may include, for example, one that would temporarily prevent pregnancy. Such a vaccine would still operate by stimulating the immune system to recognize and attack antigens, but in this case the antigens would be those of the hormones that are necessary for pregnancy. The German chemist Felix Hoffman synthesized the acetyl derivative of salicylic acid also called aspirin in 1893 in response to the urging of his father, who took salicylic acid for rheumatism. Aspirin is currently the first-choice drug for fever, mild to moderate pain, and inflammation due to arthritis or injury. Of the few anesthetic agents known to the ancients, opium and hemp were

the most important. Both were taken by ingestion or by burning the drug and inhaling the smoke. Nitrous oxide, discovered by the British chemist Sir Humphry Davy about 1800, was first used as an anesthetic in 1844 by the American dentist Horace Wells. In 1842 the American surgeon Crawford Long successfully used ethyl ether as a general anesthetic during surgery. He failed to publish his findings, however, and credit for the discovery of the anesthetic properties of ether was given to the American dentist William Morton, who in 1846 publicly demonstrated its use during a tooth extraction. In 1847 the British physician Sir James Simpson discovered the anesthetic properties of chloroform. Many other general anesthetics have since been discovered. without these medicines it would be

hard for us to cope with the deseases that come our way. Radioactive Therapy and Diagnosis: (Radiology) Radiology had its origin in the discovery of X rays by the German physicist Wilhelm Conrad Roentgen in 1895. Roentgen was awarded the first Nobel Prize in physics for his work. Medical images have subsequently been produced by means of other forms of radiant energy. Thus, ultrahigh-frequency sound waves may be so used and in the technique called magnetic resonance imaging, the images are obtained by recording the difference in relaxation time of tissue nuclei in an electromagnetic field. For this reason the term medical imaging has been proposed as more accurate than the traditional term diagnostic radiology. Therapeutic radiology, also referred to as radiation oncology, has as