Abstract:
:We have carried out a study of large malignant skin tumors (squamous cell carcinomas) and other lesions in hairless mice (groups of 38-45) intermittently exposed to ultraviolet light over a period of 15 weeks, beginning when the mice were about 10 weeks old. The several groups were given a standard diet with 0%, 0.3%, 5%, and 10% added L-ascorbic acid (vitamin C) throughout the study. No lesions developed in unirradiated control groups. The lesions were counted every 14 days for 4 months, beginning 4 weeks before the end of the period of irradiation. The observed incidence of lesions of several sizes during successive time periods was analyzed by the statistical method recommended by a committee of the International Agency for Research on Cancer. A pronounced effect of vitamin C in decreasing the incidence and delaying the onset of the malignant lesions was observed with high statistical significance.
journal_name
Proc Natl Acad Sci U S Aauthors
Dunham WB,Zuckerkandl E,Reynolds R,Willoughby R,Marcuson R,Barth R,Pauling Ldoi
10.1073/pnas.79.23.7532subject
Has Abstractpub_date
1982-12-01 00:00:00pages
7532-6issue
23eissn
0027-8424issn
1091-6490journal_volume
79pub_type
杂志文章abstract::Mineralogical processes taking place close to equilibrium, or with very slow kinetics, are difficult to quantify precisely. The determination of ultraslow dissolution/precipitation rates would reveal characteristic timing associated with these processes that are important at geological scale. We have designed an advan...
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