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Biomedical subjects

J Izsak

Publications and source records attributed to J Izsak.

8 recordsLinked to original sources
PubMed1991

Effect of aging on cold tolerance and thyroid activity in CBA/Ca inbred mice.

Relationships between cold tolerance, serum levels of thyroxine (T4), thyronine (T3), and thyrotropine (TSH), and thyroid morphometry have been investigated in male CBA/Ca inbred mice at various ages through their life span. From the data obtained it appeared that there was an age-related decrease in cold tolerance up to 18 months of age which was followed by an increase, the age effect being most apparent in relation to cold resistance and cold tolerance during the recovery period following cold exposure. The age-related changes in cold tolerance appeared to be associated with changes in the serum concentrations of T3, T4, and TSH. In contrast to the T3 serum levels which showed a decrease at 36 months, the thyroxine contents showed a perceptible decrease from the age of 12-18 months onwards. A similar pattern was observed for the TSH levels, with a peak at 21 months, followed by a decline at 30 months. A relationship with age between serum T4 level and thyroid weight was indicated together with structural changes in the thyroid gland, particularly during senescence, for example the size and number of thyroid epithelial cells had become enlarged by 30 months of age.

Acclimatization↗
PubMedDate not supplied

Comparative analysis of death cause diversity curves in various countries.

"We used diversity indices to quantify the dominance conditions of death cause frequencies [in England, Finland, Hungary, Japan, and Norway]. Plotting age-diversity values, the curves exhibit large changes in the death cause diversity/concentration by age.... The differences are mostly attributed to the site and value of the characteristic maximum. In both studied sections (Neoplasms and Circulatory Diseases) the Japan diversity curves differ considerably from corresponding curves of the European countries. Characteristic departures are observable between the diversity graphs of the male and female groups." (SUMMARY IN ITA)

Age Factors↗