Probe

(1) In surgery, a probe is a slender flexible rod with a blunt end used to explore, for example, an opening to see where it goes. (2) In molecular genetics, a probe is a labeled bit of DNA or RNA used to find its complementary sequence or locate a particular clone like homing in on a needle in a haystack.

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1. A slender rod of rigid or flexible material, with a blunt bulbous tip, used for exploring sinuses, fistulas, other cavities, or wounds. 2. A device or agent used to detect or explore a substance; e.g., a molecule used to detect the presence of a specific fragment of DNA or RNA or of a specific bacterial colony. 3. To enter and explore, as with a p.. [L. probo, to test] Probes are essential tools for DNA analysis. Every DNA molecule possesses some unique nucleotide sequences that differentiate it from all others. A p. is a relatively short fabricated fragment of DNA that matches, in lock-and-key fashion, a nucleotide sequence unique to the material that is being sought. Probes are used to test for the presence of cloned genes in bacterial or yeast colonies, for specific nucleotide sequences in samples of DNA, or for specific genes on chromosomes.

- Bowman p. a double-ended p. for the lacrimal duct.

- nucleic acid p. a nucleic acid fragment, labeled by a radioisotope, biotin, etc., that is complementary to a sequence in another nucleic acid (fragment) and that will, by hydrogen binding to the latter, locate or identify it and be detected; a diagnostic technique based on the fact that every species of microbe possesses some unique nucleic acid sequences that differentiate it from all others, and thus can be used as identifying markers or “fingerprints.”

- periodontal p. a calibrated instrument used to measure the depth and topography of periodontal pockets.

- radioactive p. nucleic acid p..

- vertebrated p. a p. made up of a series of short sections hinged together for flexibility in penetrating convoluted tracts.

- viral p. nucleic acid p..

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Prospective, Randomized, Open Blinded Endpoint Trial; Prospective, Randomized, Open Trial with Blinded Endpoint Evaluation

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probe 'prōb n

1) a surgical instrument that consists typically of a light slender fairly flexible pointed metal instrument like a small rod that is used typically for locating a foreign body (as a bullet embedded in a part of the body), for exploring a wound or suppurative tract by prodding or piercing, or for penetrating and exploring bodily passages and cavities

2) a device (as an ultrasound generator) or a substance (as radioactively labeled DNA) used to obtain specific information (as detection of a virus or location of specific segments of a nucleic acid) for diagnostic or experimental purposes <the radioactive \probe revealed the distribution of molecules in the membrane>

probe vb, probed; prob·ing vt to examine with or as if with a probe <\probe a wound> vi to search by using a probe <\probe for a bullet>

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n.

1. a thin rod of pliable metal, such as silver, with a blunt swollen end. The instrument is used for exploring cavities, wounds, fistula, and sinus channels.

2. (gene probe) a radioactively labelled cloned section of DNA that is used to detect identical sections of nucleic acid by means of pairing between complementary bases. See Northern blot analysis, Southern blot analysis.

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(prōb) [L. proba; probare to test] 1. a slender, flexible instrument designed for introduction into a wound, cavity, or sinus tract for purposes of exploration. 2. a single-stranded DNA or RNA sequence that is labeled, as by radioactivity, and used to detect the presence of a complementary nucleic acid sequence by nucleic acid hybridization (q.v.).