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A vaccine is a biological preparation that provides active acquired immunity to a particular infectious or malignant disease. [1] [2] The safety and effectiveness of vaccines has been widely studied and verified. [3] [4] A vaccine typically contains an agent that resembles a disease-causing microorganism and is often made from weakened or ...
e. The Oxford–AstraZeneca COVID‑19 vaccine, sold under the brand names Covishield [31] and Vaxzevria [1] [32] among others, is a viral vector vaccine for the prevention of COVID-19. It was developed in the United Kingdom by Oxford University and British-Swedish company AstraZeneca, [33] [34] [35] using as a vector the modified chimpanzee ...
Human papillomavirus infection ( HPV infection) is caused by a DNA virus from the Papillomaviridae family. [5] Many HPV infections cause no symptoms and 90% resolve spontaneously within two years. [1] In some cases, an HPV infection persists and results in either warts or precancerous lesions. [2] These lesions, depending on the site affected ...
In a DNA double helix, each type of nucleobase on one strand bonds with just one type of nucleobase on the other strand. This is called complementary base pairing.Purines form hydrogen bonds to pyrimidines, with adenine bonding only to thymine in two hydrogen bonds, and cytosine bonding only to guanine in three hydrogen bonds. . This arrangement of two nucleotides binding together across the ...
Biology is the scientific study of life.[1][2][3] It is a natural science with a broad scope but has several unifying themes that tie it together as a single, coherent field.[1][2][3] For instance, all organisms are made up of cells that process hereditary information encoded in genes, which can be transmitted to future generations. Another ...
Polytetrafluoroethylene is a fluorocarbon solid, as it is a high- molecular-weight polymer consisting wholly of carbon and fluorine. PTFE is hydrophobic: neither water nor water-containing substances wet PTFE, as fluorocarbons exhibit only small London dispersion forces due to the low electric polarizability of fluorine.
3LR12 (4.5-volt), D, C, AA, AAA, AAAA (1.5-volt), A23 (12-volt), PP3 (9-volt), CR2032 (3-volt), and LR44 (1.5-volt) batteries. This is a list of the sizes, shapes, and general characteristics of some common primary and secondary battery types in household, automotive and light industrial use. The complete nomenclature for a battery specifies ...
