Medical Dictionary Definitions A-Z List
Medical Dictionary Definitions A - Z - «R»:
Receptor, T-cell: A molecule on the surface of T-lymphocytes (T-cells) for recognizing specific antigens (foreign substances or microbes such as viruses)....
Receptor, visual: The layer of rods and cones, the
visual cells, of the retina....
Recessive: A condition that appears only in individuals who have received two copies of a mutant gene, one copy from each parent. The individuals with a double dose of the mutated gene are called homozygotes. Their parents, each with a single dose of the mutated gene, appear normal and are called he...
Recessive, autosomal: A genetic condition that appears only in individuals who have received two copies of an autosomal gene, one copy from each parent. The gene is on an autosome, a nonsex chromosome. The parents are carriers who have only one copy of the gene and do not exhibit the trait because t...
Recessive, X-linked: A gene on the X chromosome that
expresses itself only when there is no different gene present at that locus (spot on the
chromosome). For example, Duchenne muscular dystrophy (DMD) is an X-linked recessive
disorder. A DMD boy has the DMD gene on his sole X chromosome (and so is ...
Recipient: In medicine, a recipient is someone who
receives something like a blood transfusion or an organ transplant. The recipient is
beholden to the donor....
Reciprocal translocation: A type of chromosome rearrangement involving the exchange of
chromosome segments between two chromosomes that do not belong to the same pair of chromosomes.
A specific reciprocal translocation might, for example, involve the swap of material between chromosomes 1 and 19....
Recombinant: A person with a new combination of genes,
a combination of genes not present in either parent, due to parental recombination of
Recombinant clones: Clones containing recombinant DNA
Recombinant DNA Advisory Committee (RAC)
Recombinant DNA Advisory Committee (RAC): The National Institutes of Health (NIH) panel that oversees gene-therapy research in the U.S....
Recombinant DNA molecules
Recombinant DNA molecules: A combination of DNA
molecules of different origin that are joined using recombinant DNA technology....
Recombinant DNA technology
Recombinant DNA technology: A series of procedures used
to join together (recombine) DNA segments. A recombinant DNA molecule is constructed
(recombined) from segments from 2 or more different DNA molecules. Under certain
conditions, a recombinant DNA molecule can enter a cell and replicate there, a...
Recombinant tPA: Recombinant tissue plasminogen activator. See: Tissue plasminogen activator....
Recombination: The trading of fragments of genetic
material between chromosomes before the egg and sperm cells are created. Key features of
recombination include the point-to-point association of paired chromosomes (synapsis)
followed by the visible exchange of segments (crossing over) at X-shaped c...
RECOMBIVAX-HB: A vaccine against hepatitis B (hep B) to
stimulate the body's immune system to produce antibodies against the hep B virus....