Classification of agents

Fermentation products have played a rather minor role in the control of plant diseases. Table VI gives a classification of agents used on plants. These are divided into pesticides and growth modulators. The pesticides are classified as bactericides, fungicides, insecticides, miticides, nematicides and herbicides. There are fermentation products in each of these categories, and these are listed in Table VII. 

The penicillins [pen i SILL in] are the most widely effective antibiotics and are among the least toxic drugs known the major adverse reaction to penicillins is hypersensitivity. The members of this family differ from one another in the R substituent attached to the 6-aminopenicillanic acid residue. The nature of this side chain affects their antimicrobial spectrum, stability to stomach acid, and susceptibility to bacterial degradative enzymes (P-lactamases). Figure 30.1 shows the main structural features of the penicillins. Figure 30.2 shows the classification of agents affecting cell wall synthesis. 

A classification of agents causing occupational pigment loss is listed in Table 6. 

LOW RISK Classification of AGENTS having a minimal effect on personnel, other animals, or plants, under ordinary conditions of exposure and health. 

MODERATE RISK Classification of AGENTS having a proven PATHOGENICITY in an uncompromised host, agent used at high concen-... 

Proteins are the agents of biolo ealfunction. Virtually every cellular activity is dependent on one or more particular proteins. Thus, a convenient way to classify the enormous number of proteins is by the biological roles they fill. Table 5.3 summarizes the classification of proteins by function and gives examples of representative members of each class. 

An imidazoquinazoline constitutes still another compound that does not fall in the classification of a nonsteroid antiinflammatory agent yet shows good platelet anti aggregating activity. Condensation of benzyl chloride 128 with the ethyl ester of glycine gives alkylated product... 

The hazards of a rigid classification of substances which may modify the course of a free radical polymerization are well illustrated by the examples of inhibitors and retarders which have been cited. The distinction between an inhibitor or retarder, on the one hand, and a co-monomer or a transfer agent, on the other, is not sharply defined. Moreover, if the substance is a free radical, it is potentially either an initiator or an inhibitor, and it may perform both functions as in the case of triphenylmethyl. If the substance with which the chain radicals react is a molecule rather than a radical, three possibilities may arise (i) The adduct radicals may be completely unreactive toward monomer. They must then disappear ultimately through mutual interaction, and we have a clear-cut case of either inhibition or retarda-... 

Before proceeding further it is well to consider the term cement, for its definition can be the source of some confusion. Both the Oxford English Dictionary and Webster give two alternative definitions. One defines a cement as a paste, prepared by mixing a powder with water, that sets to a hard mass. In the other a cement is described as a bonding agent. These two definitions are quite different. The first leads to a classification of cements in terms of the setting process, while the second lays emphasis on a property. In this book the term cement follows the sense of the first of these definitions. 

WC Griffin. Classification of surface-active agents by HLB . J Soc Cosmet Chem 1 311-326, 1949. 

Griffin, W.C. (1949). Classification of Surface-Active Agents by HLB. J. Soc. Cosmetic Chemists 1, 311. 

This chapter includes four indices the Alphabetical index, the Chemical Abstract Service (CAS) numbers index, the International Classification of Diseases, 10th Revision (ICD-10) numbers index, and the Organization for the Prohibition of Chemical Weapons key (OPCW) numbers index. OPCW numbers are found in the "Handbook on Chemicals, version 2002," Appendix 2 in Declaration Handbook 2002 for the Convention on the Prohibition of the Development, Production, Stockpiling, and Use of Chemical Weapons and on their Destruction. OPCW numbers were developed to provide an easy method for tracking chemical warfare agents and precursors if CAS numbers were not available. 

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