China 
Africa 
Explore chapters and articles related to this topic
The Medlars Pricing Algorithm
Published in M. Sandra Wood, Cost Analysis, Cost Recovery, Marketing, and Fee-Based Services, 2013
Carolyn B. Tilley, David Kenton
In a letter sent in June 1983 to NLM domestic searchers notifying them of Registry of Toxic Effects of Chemical Substances and Toxicology Data Bank database price changes, NLM included a brief note about the forthcoming change in the online MEDLARS system pricing.2 Also, at the 1983 NLM Online Users Meeting, held as an unofficial meeting each year at the annual meeting of the Medical Library Association, NLM staff discussed the new pricing algorithm in terms of its three components. These components are connect hour use (which was reduced from previous connect hour charges), work performed by the computer, and characters sent to the user's terminal. Other charges, such as offline processing, page charges, and the monthly minimums for each access code, were not changed.
Prevention of poisoning
Published in Bev-Lorraine True, Robert H. Dreisbach, Dreisbach’s HANDBOOK of POISONING, 2001
Bev-Lorraine True, Robert H. Dreisbach
A sizable part of the present incidence of cancer appears to be the result of chemical carcinogenesis; estimates range from 4 to 60% or more. The Occupational Safety and Health Administration (OSHA) has established zero tolerance levels for working atmospheres for the following substances suspected of being carcinogens in humans: 2-acetylaminofluorene, 4-aminodiphenyl, benzidine (and its salts), 3,3′-dichlorobenzidine (and its salts), 4-dimethylaminoazobenzene, alpha-naphthylamine, beta-naphthylamine, 4-nitro-biphenyl, N-nitrosodimethylamine, beta-propiolactone, bis-chloromethyl ether, methylchloromethyl ether, 4,4′-methylene(bis)-2-chloroaniline, ethyleneimine (see NIOSH: Registry of Toxic Effects of Chemical Substances). Table 1.3 lists a number of suspected or confirmed environmental carcinogens. Some substances are considered possible carcinogens based on their structural similarity to vinyl chloride: bromoprene, epibromohydrin, epichlorohydrin, perbromoethylene, perchloroethylene, tribromoethylene, styrene (vinyl benzene), vinyl bromide, vinylidene bromide, and vinylidene chloride.
Searching for drug leads targeted to the hydrophobic cleft of dengue virus capsid protein
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2022
Liliane O. Ortlieb, Ícaro P. Caruso, Nathane C. Mebus-Antunes, Andrea T. Da Poian, Elaine da C. Petronilho, José Daniel Figueroa-Villar, Claudia J. Nascimento, Fabio C. L. Almeida
The toxicity risk calculations search for substructures within the chemical structure being indicative of specific toxicity according to a reference database (Registry of Toxic Effects of Chemical Substances database – RTECS), which covers compounds of different toxicity classes49,63. The absence of risky fragments suggests a low risk concerning the toxicity class under investigation63. For these studies, the toxicity classes related to mutagenic, tumorigenic, or irritant effects or being associated with reproductive effects are considered. The results for all compounds showed they do not present any toxicological risks for those classes. It is important to emphasise that these results do not eliminate the need for traditional toxicological tests.