NEC nex 2600 Manuale Proprietario

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When 20 types of glioma were considered separately, however, 
an association was found between mobile phone use and one 
rare type of glioma, neuroepithelliomatous tumors. It is possi-
ble with multiple comparisons of the same sample that this 
association occurred by chance. Moreover, the risk did not 
increase with how often the mobile phone was used, or the 
length of the calls. In fact, the risk actually decreased with 
cumulative hours of mobile phone use. Most cancer causing 
agents increase risk with increased exposure. An ongoing study 
of brain cancers by the National Cancer Institute is expected to 
bear on the accuracy and repeatability of these results.
1
2.
Researchers conducted a large battery of laboratory tests to 
assess the effects of exposure to mobile phone RF on genetic 
material. These included tests for several kinds of abnormalities, 
including mutations, chromosomal aberrations, DNA strand 
breaks, and structural changes in the genetic material of blood 
cells called lymphocytes. None of the tests showed any effect of 
the RF except for the micronucleus assay, which detects struc-
tural effects on the genetic material. The cells in this assay 
showed changes after exposure to simulated cell phone radia-
tion, but only after 24 hours of exposure. It is possible that 
exposing the test cells to radiation for this long resulted in heat-
ing. Since this assay is known to be sensitive to heating, heat 
alone could have caused the abnormalities to occur. The data 
already in the literature on the response of the micronucleus 
assay to RF are conflicting. Thus, follow-up research is neces-
sary.
2
FDA is currently working with government, industry, and 
academic groups to ensure the proper follow-up to these 
industry-funded research findings. Collaboration with the 
Cellular Telecommunications Industry Association (CTIA) in 
particular is expected to lead to FDA providing research rec-
ommendations and scientific oversight of new CTIA-funded 
research based on such recommendations.
1.
Muscat et al. Epidemiological Study of Cellular 
Telephone Use and Malignant Brain Tumors. 
In: State of the Science Symposium;1999 June 
20; Long Beach, California.
2.
Tice et al. Tests of mobile phone signals for 
activity in genotoxicity and other laboratory 
assays. In: Annual Meeting of the 
Environmental Mutagen Society; March 29, 
1999, Washington, D.C.; and personal 
communication, unpublished results.