Twelfth lunar month twenty (Gengxu year), January 21, 1911, American Rolls for the first time, cancer tumors are caused by viruses.


1911 January 21, 2010, Francis - Payton - Rolls-published medical reports proposed that cancer tumors are caused by viruses, this formulation is the first time in medical history.
"virus" is the word comes from the Latin, originally referred to an animal source of toxins. The virus can be proliferation, genetics and evolution, and thus has the basic characteristics of life, but so far it has not accepted definition. Originally used to identify the virus traits, such as the individual small, generally can not be seen under an optical microscope, by the bacteria can not pass through the filter, in the artificial medium, can not grow, and pathogenic, are still practical significance. But essentially distinguish between viruses and other biological characteristics: �� genome and protein shell containing a single kind of nucleic acid (DNA or RNA), no cell structure; �� in infected cells at the same time or later release its nucleic acid, and then to the nucleic acid replication ways proliferation, rather than binary fission proliferation; the �� strict intracellular parasitic. Viruses lack independent metabolism capacity, only in living host cells, uses the cell's biosynthetic machinery to replicate their nucleic acids and the synthesis of the protein encoded by its nucleic acid, and finally assembled into a complete infectious virus units, i.e. virions. The virion is the main form of virus spread from cell to cell or from host to host.
before the discovery of the virus, people have already begun unconsciously use viruses to serve mankind. China in the 16th century, before and after vaccination to healthy people with smallpox patients abscess slurry leaving of acquired immunity. Almost at the same time, growers in the Netherlands with a grafting method tulip infected out beautiful broken color flowers; 1796 E. Jenner invented the vaccinia vaccine; 1885 L. Louis Pasteur's first rabies vaccine.
1892 ��.��. Ivanov Sharansky found suffering from tobacco mosaic disease of tobacco juice through the filter bacteria retention, remains infectious; the 1898 MW Baiyelinke found this For a fact, and that the disease is caused by a class of pathogens and bacteria. This is the beginning of the understanding of the virus. Later have been found in many humans, plants and animals, the disease is caused by a virus. FAJ Le Fule and P. volts Luo Shi in 1898 found that bovine foot-and-mouth disease virus; 1915 the FW Te Wote 1917 F. Erel were found in bacteria and viruses that phage. the virus
since the 1930s began to explore the physical and chemical properties, M. Schlesinger purified phage and pointed out that it is constituted by proteins and DNA; 1935 WM Stanley crystallization of tobacco mosaic virus; 1936 was first seen under the electron microscope that the virus is a rod-shaped particles. After many viruses succession is purified, their morphology and chemical composition, to provide a basis for the Taxonomy of Viruses. (History TodayOnHistory.com)
simple structure and components of the virus, some viruses are easy to cultivate and quantitative, since the 1940s, the virus is always important materials for molecular biology research. The late 1930s, represented by M. Delbr��ck school scholars began with E. coli even number of T phage research replication and genetic mechanisms, to lay the foundation of molecular genetics. In the 1970s, the research focus to gradually shift the animal virus. Important progress in the development of molecular biology, such as DNA and RNA is the genetic material of conclusive evidence, the doctrine of the formation of the triplet code, elucidation of nucleic acid replication mechanism, the central dogma of genetic information flow proposed reverse transcriptase gene duplication and The discovery of continuity, as well as the rise of genetic engineering and the development of the theory of carcinogenicity, almost without exception, with the virus. The primary structure of proteins and nucleic acids analysis, and are often the first virus for the completion of the Materials Research. Molecular biology research, in turn, promote understanding of the virus structure, replication and genetic virology developed into an independent branch of disciplines.
in practice, virus prevention and treatment of viral disease of humans, plants and animals have made an important contribution. Virus vaccine development, effective measures to provide for the control of human diseases such as smallpox, yellow fever, polio, measles and poultry diseases (such as rinderpest, classical swine fever, Newcastle disease, etc.); comprehensive prevention and disease resistance breeding such as the use of measures to control the potato degenerative diseases, crop diseases of wheat soil-borne mosaic virus, cabbage, turnip mosaic virus; insect viruses as pesticides, also vigorously and has entered a practical stage .