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Antibiotics Essay Research Paper AntibioticsAn antibiotic is

Antibiotics Essay, Research Paper

Antibiotics

An antibiotic, is defined to be a drug produced by certain microbes.

Most doctors use antibiotics to help fight the germs in a patient. Antibiotics

are obtained from plants, fungi, air, water, soil, just about anything on earth.

Antibiotics kill and attack the germ or virus in the body, but do not hurt the

human cells, ordinarily. The antibiotics are used to treat many various types of

diseases, such as tuberculosis, syphilis, and several kinds of infections.

People have been using antibiotics for more than 2,500 years. They used

molds to help cure some skin infections and rashes. It was in the late 1800’s

that the real study of medicine began. Louis Pasteur discovered that bacterium

was the cause of disease, and proved wrong the theory of spontaneous generation.

After him there was Robert Koch, who developed a method of isolating and growing

bacteria. Scientists tried developing drugs that could kill microbes, but they

proved to be either dangerous or ineffective.

In 1928 there was a discovery by Alexander Fleming. He detected that a

substance he called “penicillin” destroyed bacteria. Then in the late 1930’s,

two British scientists invented a method of extracting penicillin from the mold.

This was the start of developing new drugs to treat diseases and bacteria.

Over the years, numerous thousands of antibiotic material have been

found in nature as well as produced chemically but, there are few that are safe

and useful. However the ones that are safe and effective have saved many lives

and have helped extend life expectancy.

Right now, there is more than 70 different kinds of antibiotics in use.

Most antibiotics are used to treat infections, some for fungi and protozoa, but

antibiotics are not usually effective against viruses. So they have developed

other methods such as vaccines against viruses.

Antibiotics work by one of three ways, they can one, prevent the cell

wall from growing; two, obstruct the cell membrane; or three disrupt the

chemical processes. When the antibiotic prevents the cell wall from forming, the

antitoxin surrounds the bacteria’s membrane, and then it forms a rigid wall that

stops the cell wall from splitting open, which would produce another cell. The

humans’ cells are not hurt by this because human cells do not have cell walls.

If the antibiotic obstructs the cell membrane, which controls the flow

of items in and out of the cell, then essential nourishment can escape the cell.

Then a toxic substance could enter the cell killing it. Human cells are not

effected by this method because the antitoxin only effects the microbial cells.

If the antitoxin disrupted the chemical process, then the microbe cannot

survive. The cells need the proteins and nucleic acids, that they produce to

survive, and by interfering with this process, the cell cannot persevere. Human

cells are immune to this method because, both kinds of cells produce proteins

and acids to survive, but the methods of making the proteins in each cell differ

enough for the antibiotic to be able to decipher the different methods.

Antibiotics are the safest kinds of drugs when properly used, but misuse

could lead to dangerous side effects or even death. There are three main

dangerous reactions to the antibiotics are one is allergic reactions, two is the

eradication of good microbes, and three is the damage of organs and tissues.

Most allergic reactions are not that bad. It could be a rash or a fever,

but if a person is highly allergic to what they were exposed to, they could die.

Every antibiotic made can produce an allergic reaction, but the most commons are

penicillins. Approximately 10% of people in the U.S. have an allergic reaction

to penicillins.

The antibiotic could also hurt or damage the helpful microbes. In a body,

there is sometimes some good microbes living near the bad ones. When they are

both alive, they are competing for the food. However, antibiotics could kill

more good microbes than bad ones, resulting in a higher level of multiplication.

This could also cause a new infection called a suprainfection. In this case, the

doctor will usually prescribe a secondary drug to clear up this infection.

The last side effect that an antibiotic could have is that it could

damage the organs or tissues. This kind of side effect is the least likely to

happen because the antibiotics usually only attack the microbial cells.

Sometimes, as a last resort a doctor may use such a drug as streptomycin, used

to treat tuberculosis. The overuse of such a drug could result in deafness,

kidney damage and other side effects.

Resistance to antibiotics has grown more common in recent years.

Resistance can happen in two ways. One is, when the reproduction of cells is

occurring the genetic material may get changed causing a mutation in the new

cells. These cells then become immune to the antibiotic. New research shows that,

in mutation, the cells can become immune to germs that they have never faced.

The second way is, the resistance microbes, may transfer the genetic material

to another non-resistance cell, in turn, producing a resistance cell. When

antibiotics are being used the non-resistance cells are killed, but the

resistance cells, keep multiplying, which is bad if a germ is a resistance cell.

Scientists are always trying to find new antibiotics. They test many

thousands of natural plants and chemicals. They must first test these drugs in

test tubes and then on laboratory animals. If they still show no harmful side

effects, then they are tested on humans. The human testing must first be

approved by the FDA. Then if it passes all tests on humans and is approved by

the FDA the drug may go on sale.

Antibiotics are a great invention, perhaps one of the best. They help

people survive through diseases and infections, that would otherwise kill them.

Antibiotics save lives, and there aren’t many other inventions that can do that.

Bibliography

CD-ROM Reference

“Antibiotics.” Microsoft Bookshelf. 1995 ed. Encyclopedias

“Antibiotics.” World Book Encyclopedia. 1992 ed. Magazines

“The end of antibiotics.” Newsweek 28 Mar. 1994: 47-51.




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