The urinary excretion of hydroxyproline, the amino acid specifically existent in collagen, is considered to be a reliable indicator of metabolic status of collagen, including bone matrix turnover (Prockop and Kivirikko, 1967). The increase of hydroxyproline in the daily output is found in various diseases, which influence the bone formation or resorption (Platt et al., 1964; Basu et al., 1974; Yumita, 1983). It has been proved that, for breast and prostatic cancers, the urinary excretion of hydroxyproline is not only an accurate index of skeletal involvement, but also a useful indicator to evaluate the evolution of metastatic bone disease while the patient is on therapy (Bishop· and Fellow, 1977; Niell et al., 1983). Iguchi and Sano reported an increase of the urinary hydroxy proline excretion in patients with ItaiItai disease (1974). However, it is not yet clear whether or not, the urinary hydroxyproline excretion really increase in the stage prior to the development of chronic cadmium poisoning. This paper shows the urinary levels of hydroxyproline among the inhabitants of the present area, Annaka City, where their urinary levels of cadmium was higher than those of non-polluted area. But no serious effects were observed due to the environ mental cadmium exposure.
In order to know the cause of difference in the expectation of life (ex) by prefecture, relationships between ex (e0, e20, e40, e65) by prefecture in every five years from 1965 to 1980 and constituent of river water (19 items) were examined by simple correlation, partial correlation, multiple correlation and multiple regression analysis, and the following results were obtained. 1) Correlation coefficients between ex and pH, Ca, Mg, CO2, Ca/SO4, Ca-Na were positive and significant, and those between eX and SiO2, SO4, SO4/CO3, Na/CO were negative and significant in one or some age of year. These correlations, excepting PH, were relatively strong in female and old age and showed tendencies of getting weaker year by year. 2) Of the partial correlation coefficients excluded influences of the items whose simple correlation coefficients were significant, those between ex and SO4/CO3 were chiefly significant among others until 1975, so were those between ex and PH in 1980. 3) In the multiple regression analyses of ex on items by forward selection proce dure, SO4/CO3 were selected for the first variables in the most cases until 1975, so were pH in 1980. Above results suggest that the relation of SO4/CO3 to the difference in ex by prefecture was strong, especially for female and old age, getting weaker every year, and making stronger that of pH recently.
Using the male data in 1965, the authors investigated the validity of life lost as a health indicator in eighteen countries and each prefecture of Japan. Moreover, we deviced a new health indicator "Life Gained" meaning age-corrected life gained and investigated the validity of the new indicator as a health indicator. The procedure for calculating the crude life gained is as follow : Crude Life Gained=Σ The results obtained were as follows : 1) The relationships between life lost and life span, infant death rate and corrected PMI were markedly high, but the relationships of life lost to corrected death rate and average death age were not so high. 2) The difference of corrected life lost and crude life lost was not so remarked. 3) The age of 80 years or so was adequate for the target years of age for life lost. 4) The new health indicator "Life Gained" proposed here, was very valid for the estimation of health level in the areas.
Perinatal mortality rates have been markedly reduced in Japan (Ministry of Health and Welfare, 1986). Perinatal deaths were most closely related to fetal age and weight. The infants of short gestational duration and lowbirth weight have been found to show high perinatal mortality rates (Erhardt et al., 1964; Yerushalmy 1970; Behrman et al., 1971). The reduction in perinatal mortality rates was greatest for large birth weight infants(Makino et al., 1985). Birth weight was as sociated with gestational age (Erhardt et al., 1964). Perinatal mortality by gestational age differed according to cause of death. Therefore, it is considered to be important to observe the changes in cause specific Perinatal mortality rates by gestational age. The purpose of this paper is to study the association between decrease in perinatal mortality rates and gestational age.
The present study was designed to compare the epidemiological features of habu bites among the three study areas ; Amamioshima, Tokunoshima and Okinawa. Results are as follows : 1) During the period of 8 years from 1977 to 1984, the annual incidence of habu bites showed a tendency to decrease on both Tokunoshima and Okinawa but not on Amamioshima. 2) The incidence rate of habu bite per 1000 of local population differed greatly among the study areas. However, the rate per 1000 farming population or per 100 ha farm land did not so widely differ among the areas. 3) Patterns for the monthly distribution of habu bite differed significantly among the study areas, the highest incidence was in June on Amamioshima and Tokunoshima but in October on Okinawa. 4) The incidence of habu bite increased with a rise in temperature and reached a peak at 24°C to 26°C, after which it tended to decrease. The incidence also increased steadily with an increase in humidity. 5) The distribution for the frequency of habu bite per day conformed to the negative binomial distribution on the yearly basis but to the poisson series on a monthly basis. 6) Assuming that the frequency of habu bite per head for those who have at least one bite was a truncated poisson distribution, the size of the population at risk was estimated by trial and error. The value obtained was 12, 757 or 15% of the total population for Amamioshima. Corresponding values for Tokunoshima and Okinawa were 15, 873 or 46% and 9, 877 or 1%, respectively.