“virus”的概念、定义、翻译、参考文献-科学参考

virus

Chemistry

A biological entity that reproduces inside the cells of a living host, causing it to produce thousands of copies of the virus. A virus consists of genes made of DNA or RNA and a ‘coat’ of protein that protects the genes. Sometimes there is a layer of lipid around the protein. The smallest viruses have a size of about 20 nm, with the biggest having a size of about 300 nm. The structures of viruses have been extensively studied using electron microscopes. It has been found that many viruses have the shape of a helix or an icosahedron, but more complex structures are known.

Computer

Program code written to replicate by attaching copies of itself to other objects within the system, and normally also having a detrimental effect. This may range from generation of irritating messages, through denial of service, to corruption or complete destruction of data. A program virus will seek out and copy itself into other program files whenever a previously infected program is run. A boot sector virus copies itself into that sector of a disk and spreads whenever a system is boot loaded from an infected disk. Viruses are spread when infected programs or disks are transferred to previously clean systems. See also logic bomb, Trojan horse, worm.

Internet

A computer program which enters a computer, usually via a network connection, and carries out a malicious act. This can range from the less serious, such as displaying a splash screen with an obscene message, to the potentially disastrous, such as deleting all the files on an enterprise’s hard drive.

Electronics and Electrical Engineering

A program or piece of code that is loaded onto a computer without the user’s knowledge and runs against the user’s wishes. All computer viruses are man-made and can replicate themselves. Recently many antivirus programs have become available. These programs periodically check the computer systems on which they are installed for known types of viruses and can disinfect the system if a virus is found.

Biology

A particle that is too small to be seen with a light microscope or to be trapped by filters but is capable of independent metabolism and reproduction within a living cell. Outside its host cell a virus is completely inert. A mature virus (a virion) typically ranges in size from 20 to 600 nm in diameter. It consists of a core of nucleic acid (DNA or RNA) surrounded by a protein coat (see capsid). Some (the enveloped viruses) bear an outer envelope consisting of proteins and lipids. Inside its host cell the virus initiates the synthesis of viral proteins and undergoes replication. The new virions are released when the host cell disintegrates. Viruses are parasites of animals, plants, and some bacteria (see bacteriophage). Viral diseases of animals include the common cold, influenza, AIDS, herpes, hepatitis, polio, and rabies (see adenovirus; arbovirus; herpesvirus; hiv; myxovirus; papovavirus; picornavirus; poxvirus); some viruses are also implicated in the development of cancer (see retrovirus). Plant viral diseases include various forms of yellowing and blistering of leaves and stems (see tobacco mosaic virus). Antiviral drugs are effective against certain viral diseases and vaccines (if available) provide protection against others. See also interferon; nucleocytoplasmic large DNA virus; pandoravirus. See Feature.

单词	virus
释义	virus Chemistry A biological entity that reproduces inside the cells of a living host, causing it to produce thousands of copies of the virus. A virus consists of genes made of DNA or RNA and a ‘coat’ of protein that protects the genes. Sometimes there is a layer of lipid around the protein. The smallest viruses have a size of about 20 nm, with the biggest having a size of about 300 nm. The structures of viruses have been extensively studied using electron microscopes. It has been found that many viruses have the shape of a helix or an icosahedron, but more complex structures are known. Computer Program code written to replicate by attaching copies of itself to other objects within the system, and normally also having a detrimental effect. This may range from generation of irritating messages, through denial of service, to corruption or complete destruction of data. A program virus will seek out and copy itself into other program files whenever a previously infected program is run. A boot sector virus copies itself into that sector of a disk and spreads whenever a system is boot loaded from an infected disk. Viruses are spread when infected programs or disks are transferred to previously clean systems. See also logic bomb, Trojan horse, worm. Internet A computer program which enters a computer, usually via a network connection, and carries out a malicious act. This can range from the less serious, such as displaying a splash screen with an obscene message, to the potentially disastrous, such as deleting all the files on an enterprise’s hard drive. Electronics and Electrical Engineering A program or piece of code that is loaded onto a computer without the user’s knowledge and runs against the user’s wishes. All computer viruses are man-made and can replicate themselves. Recently many antivirus programs have become available. These programs periodically check the computer systems on which they are installed for known types of viruses and can disinfect the system if a virus is found. Biology A particle that is too small to be seen with a light microscope or to be trapped by filters but is capable of independent metabolism and reproduction within a living cell. Outside its host cell a virus is completely inert. A mature virus (a virion) typically ranges in size from 20 to 600 nm in diameter. It consists of a core of nucleic acid (DNA or RNA) surrounded by a protein coat (see capsid). Some (the enveloped viruses) bear an outer envelope consisting of proteins and lipids. Inside its host cell the virus initiates the synthesis of viral proteins and undergoes replication. The new virions are released when the host cell disintegrates. Viruses are parasites of animals, plants, and some bacteria (see bacteriophage). Viral diseases of animals include the common cold, influenza, AIDS, herpes, hepatitis, polio, and rabies (see adenovirus; arbovirus; herpesvirus; hiv; myxovirus; papovavirus; picornavirus; poxvirus); some viruses are also implicated in the development of cancer (see retrovirus). Plant viral diseases include various forms of yellowing and blistering of leaves and stems (see tobacco mosaic virus). Antiviral drugs are effective against certain viral diseases and vaccines (if available) provide protection against others. See also interferon; nucleocytoplasmic large DNA virus; pandoravirus. See Feature.
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