See Also: Divine Providence Health Center Avera Health(health)
Dells Area Health Center Avera Health(health)
Hegg Memorial Health Center Avera Health(health)
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Sun Health(health)
Health Net(finance)
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IMS Health(finance)
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Compression (health) and DNA (sh)


Compression (health)


1. The act of pressing together. As in a compression fracture, nerve compression, or spinal cord compression. 2. To shorten in time. In embryology, there may be compression of development with some stages even omitted.





DNA (sh)




or deoxyribonucleic acid

One of two types of nucleic acid (the Other is RNA); a complex organic compound found in all living cells and many viruses.

It is the chemical substance of genes. Its structure, with two strands wound around each Other in a double helix to resemble a twisted ladder, was first described (1953) by Francis Crick and James D. Watson. Each strand is a long chain (polymer) of repeating nucleotides: adenine (A), guanine (G), cytosine (C), and thymine (T). The two strands contain complementary information: A forms hydrogen bonds (see hydrogen bonding) only with T, C only with G. When DNA is copied in the cell, the strands separate and each serves as a template for assembling a new complementary strand; this is the key to stable heredity. DNA in cells is organized into dense protein-DNA complexes (see nucleoprotein) called chromosomes. In eukaryotes these are in the nucleus, and DNA also occurs in mitochondria and chloroplasts (if any). Prokaryotes have a single circular chromosome in the cytoplasm. Some prokaryotes and a few eukaryotes have DNA outside the chromosomes in plasmids. See also Rosalind Franklin; genetic engineering; mutation; Maurice Wilkins.