.. t 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 its principal basis the use of ionizing radiation. Increasingly common, however, is the use in conjunction with radiation therapy of other forms of treatment, such as hyperthermia. all these radioactive procedures are same they just vary in the intensity of radiation they use.
chemoteraphy for example is letting the patient be bombarded with radiation to treat cancerus cells that have invaded a persons body. the CT scaner and the MRI scaner are both machines use to diagnose people to find out whats wrong with there body. for some deseases can’t be detected by just looking at a persons physical aspect. these desises are internal and must be diagnosed and trated with radiation for them to be seen. Weapons and Defense: Handguns, or pistols, as they are also known, were not popular until after the development of the wheel lock, the first practical mechanical ignition device, in the first half of the 16th century.
Most early handguns were too cumbersome to be carried in a holster by anyone on foot, and the short barrels limited their accuracy and the distance they could propel bullets. As a result, handguns were primarily used by cavalry troops in what amounted to hit-and-run tactics. As ignition systems were improved, it became possible to reduce the overall size and weight of handguns, until during the 18th century they became equally popular for use by foot soldiers. From the last half of the 17th century to the first quarter of the 19th century, most European and United States military handguns had flintlock. and barrels 23 to 30 cm.
in length; smaller pocket handguns were also made for civilian use. No significant improvements were made, however, until after 1836, when the American inventor Samuel Colt patented a revolver design combining the metal percussion cap, interchangeable mass-produced parts, and the revolving cylinder, which rotated and locked automatically when the hammer was cocked. Improvements in ammunition were introduced with the development of the self-primed metallic cartridge in the mid-19th century. Minor improvements in revolver design continued until the beginning of the 20th century, when emphasis in development was redirected to the magazine-loaded semiautomatic handgun. Since then, the semiautomatic has steadily gained in popularity and is now the primary military handgun of the world.
It is gradually replacing the revolver for police use. Modern semiautomatic handguns carry two or three times more ammunition than revolvers and are faster to reload. Their flat configuration generally makes them easier to conceal. Even with the increased ammunition capacity, using newly developed lightweight materials makes their loaded weight about the same as that of older designs. Proponents of revolvers claim greater accuracy, reliability, and safety, however, so it is unlikely that semiautomatics will totally replace revolvers.
In fact, muzzle-loading pistols and revolvers continue to be used for sport and specialized worldwide competition. also bombs are used in todays world to protect nations from invading ones. and thus came the invention In the early 1970s new types of conventional bombs, the so-called smart or guided bombs, were developed for precision bombing in Vietnam. Maneuverable bombs guided by a laser beam directed from the aircraft and reflected from the target can destroy such targets as tanks or emplacements on contact. Other types can be designed to guide themselves to targets radiating heat, such as power plants, or can be guided to the target from the delivery aircraft.
In the latter case the bomb transmits a picture of the target picked up by an on-board television camera. Remote operating devices can then guide the bomb into direct contact with a bridge, for example, or other objective. Laser-guided bombs can be used at night; television-camera guided weapons are limited to daylight use, however. and The A-bomb was developed, constructed, and tested by the Manhattan Project, a massive United States enterprise that was established in August 1942, during World War II.
Many prominent American scientists including the physicists Enrico Fermi and J. Robert Oppenheimer, and the chemist Harold Urey, were associated with the project, which was headed by a U.S. Army engineer, Major General Leslie Groves. these forms of weaponry may be destructive in most cases but they do play a vital role in protecting ones self in the society we live in. The advantages and disadvantages of technology: Technology plays a vital role in our society.
without it we can’t evolve and cope up with the ever changing world we live in. some of its advantages are the increase in efficiency and productivity of how we do and manage things. we can do things twice as fast and twice more efficient than we did a century ago. and this makes up for the growing population of the world, so that everyone may have enough to support themselves and satisfy there needs. Technology gives us larger possibilities by giving us ideas that we havent thought about in the past.
we can do more things now that technology has helped us evolve. it further enhances our perspective in the things we do. and makes simpler solutions in the problems we face everyday. it also gives us easier accessibility and mobility. it makes production move faster.
communication more efficient and cost worthy. we can now get information almost anywhere and with these information we get, we use them in our daily lives. but not everything that technology has to offer is good. for every advantages technology gives us it also comes with a subsequent disadvantages.
some of them are the complexities of society. not everyone can cope with the advancements of technology. these people can get left behind. everything becomes more complicated and what is expected of us also grows.
life was more simple in the old days. but due to technology everything has become more complex. another is the increase of indolence in our society. since everything has become more accessible and more convenient people tend to log off and become lazy. this is a very big problem to us. it decreases our morality and soon we will be so engulfed in it we cant get out from its grip.
with better solutions and easier work load comes the over dependence of people to technology. the tend not to think for them selves anymore and let technology take over there lives. this is bad for its makes us the slaves of technology instead of us controlling them they are the ones that control us. technology is important in every society. but if we insist on using and depending on it a lot it can also destroy us.
so we must think for ourselves if it is worth it and use it as we see fit.
