FIELD T-Z 

 Columns 58, 59, 60, and 61 



845 Karyolysis or karyorrhexis 



418F Muclnoid degeneration 



418G Fibrinoid degeneration 46 



418H Demyellnation 



418J Necrosis, hemorrhagic 



418K Necrosis, caseus 



2724 Fibrosis; the formation of fibrous tissue 



2725 Fibrosis specifically for adhesion 



2726 Replacement fibrosis, specifically 



replacing fatty tissue 



2727 Replacement fibrosis, tissue replaced 



unspecified 

 421 Casts, concretions, unspecified. Use 

 Symbol 421 only if specific casts or 

 concretions are not identified (Symbols 47 



FA2-, FA3-, or FA4-, for mineral 

 deposits, calcifications, urate or 

 cholesterol deposits). 



43 Neoplasia (the formation of a new, 



abnormal growth [neoplasm] the compo- 

 nent cells increasing in number and 

 being altered from a normal character 

 though they may retain some similarity 

 to the normal cells from which they are 

 derived). Use Symbol 413 for hyperplasia 5 

 (enlargement of a part due to increase 

 of cells which retain their normal 

 character, not a neoplasm). Use 51 



Symbol 43 only with Symbol 7 (or 8, 9, 

 A, or C) in Field T-1 and identify the 

 tumor or tumor type produced in Field E; 

 i. e. , use Symbol 43 only when the test 

 compound produces (or is tested to 

 produce) a tumor (indicating carcino- 

 genic action). If a pre-existing tumor 

 is treated with the test compound, use 

 Symbol 44, 45, or 46. 



44 Tumor growth; size of a pre-existing 



tumor (treated by the test compound) or 511 



rate of tumor growth. Use Symbol 44 

 only with Symbol 1, 2, or 3 (or 8, 9, A, 

 or C) of Field T-1. Code Field E with 

 the tumor identity, if known, or the 

 tumor type or with Symbol S. (Use only 512 



Symbol 43 for tumor production by the 

 test compound. ) Acceleration or retar- 

 dation of a lethal tumor is always 

 evaluated in Field Y by Criterion 12 or 

 57, using Symbol 44 in Field T-2 and 

 Symbol 1, 2, or 3 In Field T-1. 



45 Tumor regression; reduction in size of a 



pre-existing tumor treated by the test 513 



compound. Symbol 45 will ordinarily 



be reasonably used only with Symbol 7 



(or 8, 9, A, or C) in Field T-1. Its use 5131 



with Symbol 1 or 2 of Field T- I to code 



slowing or speeding of a naturally 



regressing tumor is improbable. Code 



Field E with the tumor identity, if 



known, or tumor type, or with Symbol S. 



(Use only Symbol 43^ for tumor 

 production by the test compound. ) 



Tumor metastasis ( process of ); spread of 

 a pre-existing tumor treated by the test 

 compound (not the growth rate of any 

 one secondary growth). Use Symbol 46 

 with Symbol 7, 1, 2, or 3 (or 8, 9, A, 

 or C) in Field T-1. Code Field E with 

 the tumor identity, if known, or tumor 

 type, or with Symbol S. Code the 

 primary site of the tumor in Field H-1; 

 do not code the site of metastasizing. 

 (Use only Symbol 43 for tumor produc- 

 tion by the test compound. ) 



Tumor incidence; incidence of spontane- 

 ously occurring tumors or incidence of 

 tumors induced by physical factors 

 other than the test compound . Use 

 Symbol 47 only with Symbol 1 or 2 (or 

 8, 9, A, or C) of Field T-1. Code 

 Field E with the tumor identity, if known, 

 or tumor type, or with Symbol S. (Use 

 only Symbol 43 for tumor production by 

 the test compound. ) 



Adaptive effects. (Symbol 5 is of im- 

 probable use; specific adaptive effects 

 are indicated by 51, 511, 512, etc.) 



Tolerance; resistance; refractoriness; 

 lack of sensitivity. Use Symbol 51 

 only when it is not known whether the 

 phenomenon occurs in an individual of 

 the test organism species during its 

 lifetime (Symbol 512 or 513) or occurs 

 to the species due to selection over 

 several generations (Symbol 511). 

 Consult the Key for an explanation of 

 the use of Symbol 51 and the coding of 

 Field T-1 when this symbol is in Field T-2. 



Inheritable tolerance; production of a 

 race tolerant to the test compound due 

 to exposure to the test compound. Con- 

 sult the Key for an explanation of the 

 use of Symbols 51, 511, and 512. 



Individual tolerance (physiological 

 tolerance); increase in tolerance to the 

 test compound during the lifetime of 

 the individual of the test organism 

 species due to administration of the 

 test compound. Consult the Key for 

 an explanation of the use of Symbols 

 51, 511, and 512. 



Tolerance by tachyphylaxis. Consult 

 Key for an explanation of the use of 

 Symbols 51, 511, 512, and 513. 



Cross -tachyphylaxis; tolerance to a 

 secondary compound (Field D) due to 

 tachyphylaxis by the test compound. 

 Consult the Key. 



151 - 



