Quaternary Ammonium Compounds: Derivatives of ammonium compounds, NH4+ Y-, in which all four of the hydrogens bonded to nitrogen have been replaced with hydrocarbyl groups. These are distinguished from IMINES which are RN=CR2.Benzalkonium Compounds: A mixture of alkylbenzyldimethylammonium compounds. It is a bactericidal quaternary ammonium detergent used topically in medicaments, deodorants, mouthwashes, as a surgical antiseptic, and as a as preservative and emulsifier in drugs and cosmetics.Disinfectants: Substances used on inanimate objects that destroy harmful microorganisms or inhibit their activity. Disinfectants are classed as complete, destroying SPORES as well as vegetative forms of microorganisms, or incomplete, destroying only vegetative forms of the organisms. They are distinguished from ANTISEPTICS, which are local anti-infective agents used on humans and other animals. (From Hawley's Condensed Chemical Dictionary, 11th ed)Trimethyl Ammonium Compounds: QUATERNARY AMMONIUM COMPOUNDS containing three methyl groups, having the general formula of (CH3)3N+R.Iodine Compounds: Inorganic compounds that contain iodine as an integral part of the molecule.Ammonium Compounds: Inorganic compounds that include a positively charged tetrahedral nitrogen (ammonium ion) as part of their structure. This class of compounds includes a broad variety of simple ammonium salts and derivatives.Cetylpyridinium: Cationic bactericidal surfactant used as a topical antiseptic for skin, wounds, mucous membranes, instruments, etc.; and also as a component in mouthwash and lozenges.Cetrimonium Compounds: Cetyltrimethylammonium compounds that have cationic detergent, antiseptic, and disinfectant activities. They are used in pharmaceuticals, foods, and cosmetics as preservatives; on skin, mucous membranes, etc., as antiseptics or cleansers, and also as emulsifiers. These compounds are toxic when used orally due to neuromuscular blockade.Anti-Infective Agents, Local: Substances used on humans and other animals that destroy harmful microorganisms or inhibit their activity. They are distinguished from DISINFECTANTS, which are used on inanimate objects.Glutaral: One of the protein CROSS-LINKING REAGENTS that is used as a disinfectant for sterilization of heat-sensitive equipment and as a laboratory reagent, especially as a fixative.Chlorhexidine: A disinfectant and topical anti-infective agent used also as mouthwash to prevent oral plaque.Drug Resistance, Bacterial: The ability of bacteria to resist or to become tolerant to chemotherapeutic agents, antimicrobial agents, or antibiotics. This resistance may be acquired through gene mutation or foreign DNA in transmissible plasmids (R FACTORS).Microbial Sensitivity Tests: Any tests that demonstrate the relative efficacy of different chemotherapeutic agents against specific microorganisms (i.e., bacteria, fungi, viruses).Ammonium Sulfate: Sulfuric acid diammonium salt. It is used in CHEMICAL FRACTIONATION of proteins.Choline: A basic constituent of lecithin that is found in many plants and animal organs. It is important as a precursor of acetylcholine, as a methyl donor in various metabolic processes, and in lipid metabolism.Staphylococcus: A genus of gram-positive, facultatively anaerobic, coccoid bacteria. Its organisms occur singly, in pairs, and in tetrads and characteristically divide in more than one plane to form irregular clusters. Natural populations of Staphylococcus are found on the skin and mucous membranes of warm-blooded animals. Some species are opportunistic pathogens of humans and animals.Drug Resistance, Microbial: The ability of microorganisms, especially bacteria, to resist or to become tolerant to chemotherapeutic agents, antimicrobial agents, or antibiotics. This resistance may be acquired through gene mutation or foreign DNA in transmissible plasmids (R FACTORS).Ammonium Chloride: An acidifying agent that has expectorant and diuretic effects. Also used in etching and batteries and as a flux in electroplating.Anti-Bacterial Agents: Substances that reduce the growth or reproduction of BACTERIA.Staphylococcus aureus: Potentially pathogenic bacteria found in nasal membranes, skin, hair follicles, and perineum of warm-blooded animals. They may cause a wide range of infections and intoxications.Bacterial Proteins: Proteins found in any species of bacterium.Escherichia coli: A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.Ammonium Hydroxide: The hydroxy salt of ammonium ion. It is formed when AMMONIA reacts with water molecules in solution.Ammonia: A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as AMMONIUM HYDROXIDE.Molecular Structure: The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.Nitrogen: An element with the atomic symbol N, atomic number 7, and atomic weight [14.00643; 14.00728]. Nitrogen exists as a diatomic gas and makes up about 78% of the earth's atmosphere by volume. It is a constituent of proteins and nucleic acids and found in all living cells.