Generic substances

A generic substance represents more than one substance or a set of specific substances. This set of substances can be represented by a generic or Markush structure. An important use of generic structures in the literature is that they provide a compact representation of a set of specific substances. They are also commonly used to show the way the value of a particular physical or biological property varies as a particular... 

Elixir is a Ferment of which the smallest quantity will amalgamate a large mass of any generic substance, or substance with which it has affinity, into a confection like unto itself Here the confection signifies the spirit of the life of man, and the internal balsam of life. It is that internal conserver which preserves the body in a fitting condition. Elixir is also an external balsam, extracted and prepared from external things into a Spagyric ferment. Or ... 

Some substances of interest are described in generic terms only. These generic substances may be composed of a finite number of isomeric forms, where the potential number of different individual isomers can range from two (e.g. endosulfan) to more than 200 (e.g. polybrominated diphenyl ethers), of which only a few are of environmental relevance. Moreover, it is often difficult or impossible to analyse all these isomers. 

This second option is usually adopted in simple reference price systems where each category of drugs comprises only products based on the same generic substance. 

For brevity we use parenthesis, e.g., (CsSb), to denote a generic substance without specifying its exact chemical composition by, for example. CsjSb. 

Substance information such as chemical structures, molecular formulas, and chemical names Is stored in the REGISTRY database. This is the largest collection of chemical substance Information worldwide (see Section 3,1,2), While REGISTRY contains information on specific substances, generic substances are covered by MARPAT, Generic structures are called Markush structures after the American chemist Eugene Markush, who introduced these structures in the patent literature in 1924, MaRPAT comprises generic structures from the patent literature since 1988 (see Structure Representation). Chemical reactions or molecular transformations are covered by CASREACT (see also Reaction Databases). CASREACT has been indexed since 1985 and currently holds 2.9 million chemical reactions from the chemical and patent literature,... 

The controversy seemed then to be closed. In 1890 Hantzsch had already started his work on the structure of oximes, and his synthetic work on heterocycles was practically ended. However, 27 years later, in July 1919, Tcherniac published a new paper entitled TTiiocyanoacetone and its derivatives as isomerides (33), where, after the description of improved and generalized methods for the preparation of thiocyanoacetone he came to the explosive conclusion that the substance which has been known since 1887 as hydroxymethylthiazole is not a thiazole at all. It might be called 2-imino-4-methylthioxole, but for the sake of simplicity, and in view of the now proved existence of two other isomerides of thiocyanoacetone, it seems preferable to adopt the generic... 

A widely prescribed drug for the treatment of gastric ulcers with the generic name cimetidine is a synthetic imidazole derivative Firefly luciferm is a thiazole derivative that IS the naturally occurring light emitting substance present m fireflies... 

The Textile Eiber Product Identification Act (TEPIA) requires that the fiber content of textile articles be labeled (16). The Eederal Trade Commission estabhshed and periodically refines the generic fiber definitions. The current definition for a polyester fiber is "A manufactured fiber ia which the fiber-forming substance is any long-chain synthetic polymer composed of at least 85% by weight of an ester of a substituted aromatic carboxyUc acid, including but not restricted to terephthalate units, and para substituted hydroxyben2oate units."... 

Asphalt [8052-42-4] is defined by the American Society for Testing and Materials (ASTM) (1) as a dark brown to black cementitious material in which the predominating constituents are bitumens that occur in nature or are obtained in petroleum processing. Bitumen is a generic term defined by ASTM as a class of black or dark-colored (soHd, semisoHd, or viscous) cementitious substances, natural or manufactured, composed principally of high molecular weight hydrocarbons, of which asphalts, tars, pitches, and asphaltites are typical. 

STRATEGY Suppose that the concentration of a substance A is increased but no other concentrations change. From the generic rate law, Rate = felA] , B 6, we know that as the concentration of A increases by the factor f, the rate increases by fa. To isolate the effect of each substance, if possible, compare experiments that differ in the concentration of only one substance at a time. 

It is seen that to identify the impurities, the column appeared to be significantly overloaded. Nevertheless, the impurities were well separated from the main component and the presence of a substance was demonstrated in the generic formulation that was not present in the Darvocet . The mobile phase was 98.5% dichloromethane with 1.5% v/v of methanol containing 3.3% ammonium hydroxide. The ammoniacal methanol deactivated the silica gel but the interaction of the solutes with the stationary phase would still be polar in nature. In contrast solute interactions with the methylene dichloride would be exclusively dispersive. 

The generic term carbohydrate includes monosaccharides, oligosaccharides and polysaccharides as well as substances derived from monosaccharides by reduction... 

Bioavailahility studies are used to compare different formulations of the drug product, or different batches of the same formulation and, as discussed in Chapter 8, generic copies of a reference drug. Their comparative value is based on the premise that, if similar amounts of identical active substance are delivered to the site of action at similar rates, then a similar biological response can be expected, which leads to the conclusion that the two preparations are bioequivalent. 

The EU will accept applications without supporting pre-clinical and clinical data, if it can be demonstrated that the active substances have been in well-established medical use in the Community for at least 10 years, with recognised efficacy and an acceptable level of safety. This route would be appropriate for many common over-the-counter (OTC) products. Safety and efficacy is supported by providing copies of published scientific literature as part of the submission that is, the submission relies on safety and efficacy data available in the public domain, as opposed to confidential data from authorised applications that is the cornerstone of generic applications. 

Regulatory and advisory bodies publish methods for ambient air analysis such as those issued by the British Standards Inshtute and the US Environment Protechon Agency (Tables 10.24 and 10.25, respectively). Methods for assessment of workplace air are published by the Health and Safety Executive. Some of these are generic methods (Table 10.26) whilst others are compound specihc (Table 10.27). Examples of other official methods for moihtoring workplace air quality are those published by the British Standards Inshtute (Table 10.28), and the US Nahonal Institute of Occupational Safety and Health (Table 10.29). Table 10.30 provides addihonal guidance on analytical techniques for a selection of substances. 

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