In human populations

Epidemiology is a discipline within the health sciences that deals with the study of the occurrence of disease in human populations. Epidemiologists arc generally concerned with groups of people who share certain characteristics. 

There is no evidence that maternal consumption of caffeine, even in relatively large amounts, has any long-term effects on the offspring. However, it must be remembered that such studies are very difficult to carry out in human populations. Therefore, in my judgment, the lack of evidence linking maternal caffeine consumption with long-term consequences to the offspring does not mean that such an association does not exist. 

The health effect side of the diagram shows that unit risk estimates result from interactive analyses of health-affecting processes in the human body and observed effects in human populations (epidemiology). Health effects are identified by integrating clinical studies on humans or animals with studies of physical and chemical responses to pollutant agents in the human body. 

Maizels, R.M., Bundy, D.P., Selkirk, M.E., Smith, D.F. and Anderson, R.M. (1993) Immunological modulation and evasion by helminth parasites in human populations. Nature 365, 797-805. 

The biosphere includes ecological niches where microbes peacefully co-exist with their eukaryotic host in the human this includes the concept of the micro-biome [14], which is defined as the totality of microbial organisms that co-habit with human beings. On the other hand, microbial colonization of human mucosal surfaces or prosthetic devices, often results in the development of biofilms, with significant deleterious effects on human health [15]. These are some of the challenges in infectious diseases that reflect the need to maximally utilize genomic sequence information and related sciences to better control microbial disease in human populations, and to develop anti-microbial agents with a better therapeutic index. 

Hall D, Ybazeta G, Destro-Bisol G et al. Variability at the uridine diphosphate glucuronosyltransferase 1A1 promoter in human populations and primates. Pharmacogenetics 1999 9 591-599. 

The strategy we suggest is not the only one that could be adopted, and it is clear that it will need refinement as more is learned about patterns of variation in human populations, and especially about the genetic basis of both common dis-... 

There may be similar incidences of tumors in aging people, but the real prevalence of tumors in human populations is uncertain. In the United States, where autopsies are uncommon, over one-third reveal previously undiagnosed cancers when they are conducted (Silverberg, 1984). A single type of neoplasm, renal adenoma, is present in 15-20% of all adult kidneys (Holm-Nielson and Olsen,... 

Cancer. No studies have been conducted in human populations to determine whether mirex or chlordecone causes cancer. However, studies in mice and rats have demonstrated the ability of mirex to cause liver tumors (Innes et al. 1969 NTP 1990 Ulland et al. 1977a), pheochromocytomas (NTP 1990), and rare renal tumors (NTP 1990). A study in mice and rats also showed the ability of chlordecone to increase liver tumors (NC11976). As indicated above, available data on the genotoxicity of mirex and chlordecone indicate that these chemicals do not cause cancer by a mutagenic mechanism but rather by tumor promotion. Both mirex and chlordecone are considered by the DHHS to be substances that may reasonably be anticipated to be carcinogens and by IARC to be possible human carcinogens. EPA has not classified mirex or chlordecone as to their carcinogenicity. 

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