Дайте ответы на английском языке по тексту ниже.

1. Where can the problem of discovering new antibiotics be solved?
2. What has been established experimentally?
3. When has modern medicine been making extensive use of various antibiotics?
4. What doses can the tatracyclines be given orally in ordinary use?
5. How many drugs had Russia produced before new generation of antibiotics made its appearance?
1. What are powerful agents in combating infections?
2. Which fields of medicine has non-toxic preparation found wide application in?
3. When was chlortetracycline isolated from biomycin?
4. Why was it marked as auremucin?
5. What advantages does tetracycline possess over its sister compounds?

Since the end of the twentieth century modern medicine has been making an extensive use of various antibiotics. It should be noted that antibiotics are powerful agents in combating infections. The problem of discovering new antibiotics can be most successfully solved at special research institutes which may have a small experimental plant producing preparations of new antibiotics.
Russia has several research institutes working in this field. Before new generation of antibiotics made its appearance Russian science had produced a series of new effective drugs, such as albomycin, etc. This practically non-toxic preparation has found wide application in the treatment of pneumonia in newborn and small children. It is also successfully used in obstetric and gynecological practice. Surgeons have to use it during the treatment of the septic processes caused by staphylococci which can resist other antibiotics. It has been established experimentally that the composition of its molecule includes iron and it has a peculiar mechanism of affecting the bacteria.
Mention must also be made of tetracyclines, such as chlortetracycline. It was introduced after chlorphenol had been discovered. Therefore chlortetracycline was considered the second broad – spectrum antibiotic developed for therapeutic purposes. It was isolated in 1948 from biomycin. Because of its yellow colour it was marked as auremycin. Another antibiotic of this series is tetracycline. It has been found that it possesses great advantages over its sister compounds. It may produce less toxic effect and penetrate the cerebrospinal fluid to a much greater extent. It has been stated that in ordinary use the tetracyclines can be given orally in doses of 250 mg.