quellung reaction
Học thuậtThân thiện
Definition
- Noun:
- A specific immunological reaction: The "quellung reaction" is a laboratory phenomenon where the capsule surrounding certain bacteria visibly swells when exposed to specific antibodies. This swelling is used to identify the bacterial species or serotype.
Usage
- The "quellung reaction" is a technical term used primarily in microbiology, immunology, and medical diagnostics.
- It describes a confirmatory test result. One observes to identify an organism.
- It is often used with the name of the bacterium being identified (e.g., pneumococcus quellung).
Examples
- Noun:
- The laboratory confirmed the presence of Streptococcus pneumoniae by observing a positive quellung reaction.
- The quellung reaction forms the basis of the Neufeld test for typing pneumococci.
Advanced Usage
- "To demonstrate a quellung reaction": This phrase is used to describe the action of performing the test and obtaining a positive result.
- The antiserum caused the capsule to swell, demonstrating a clear quellung reaction.
Variants and Related Words
- Quellung (noun): Sometimes used alone as a shorter form to refer to the same swelling phenomenon.
- Capsular quellung is a key diagnostic feature.
- Neufeld reaction (noun): A synonym, named after the bacteriologist who described it.
- Capsular swelling test (noun): A descriptive synonym for the procedure.
Synonyms
- Capsular swelling reaction: A more descriptive synonym.
- Neufeld test: Specifically refers to the test procedure that relies on the quellung reaction.
Notes on Meaning
- The term is highly specific to a single laboratory technique and result. It does not have general or figurative meanings.
- The core concept is the visible, antibody-induced swelling ( is German for "swelling") of a bacterial capsule, which allows for microscopic identification.
Noun
- the swelling of the capsule surrounding a microorganism after reaction with an antibody; the basis of certain tests for identifying microorganisms
- pneumococcus quellung