Vitamin E (50mg/kg/day, as DL-α -tocopherol acetate), Selenium (0.2066mg/kg/day, as sodium selenite) and Methylmercury (0.30mg/kg/day, as methylmercuric chloride) were administered per os. Methylmercuric chloride (MMC) and VE were administered to six cats (Group A) for 100 days with pretreatment of VE for 100 days, MMC and Se were administered to six cats (Group B) for 100 days with pretreatment of Se for 50 days, MMC, VE and Se were administered to six cats (Group C) for 100 days with pretreatment of VE for 100 days and Se for 50 days, MMC was administered solely to four cats (Group D) for 100 days without pretreatment. Four other cats (Group E) were the control.
Treatment with VE+Se or VE along with MMC clearly decreased mortality but treatment with Se along with MMC produced no statistical evidence for a decrease in mortality.
Treatment with VE+Se along with MMC statistically restrained a loss in weight due to the toxicity of MMC, but the graph of body weight showed the effectiveness of VE+Se and VE in the first half as well as Se in the latter half of the treatment period. Continual examination with a mathematical model devised by me showed the effectiveness of VE+Se and VE (VE+Se: VE=3:1), but did not clearly show the effectiveness of Se. The treatments were more effective in the latter than in the first half during the treatment periods for all groups.
No symptoms appeared in histological sections from the cerebrum and kidney of each group. VE prevented the toxicity of MMC to a degree as did Se. VE+Se almost completely prevented the toxicity of MMC in the cerebellum, and VE prevented the toxicity of Se in the liver.
VE increased the concentration of MeHg in the cerebrum. Se decreased the concentration of T-Hg and MeHg but VE tended to interfere with the effect of Se in the cerebellum. VE, Se and VE+Se caused excretion of T-Hg and VE the excretion of MeHg into the hair. VE tended to conserve Se in the organs and in the blood by itself or with Hg.
We hypothesized that the administration of VE and Se, and the intensification of Se, qualitatively or quantitatively, by VE, might increase the critical concentration for the toxicity of Hg or the upper limit for the accumulation of Hg.

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Epidemiological features of habu-bite in the Amami Islands were investigated. Over a period of 5 years (1972 to 1976) 1285 cases of habu-bite, including 11 deaths, were recorded on Tokunoshima and Amamioshima. The total number of victims was 1265, of which 1246 were attacked once, 18 twice and 1 three times during the 5 year period. Assuming that the frequency of habu-bite per head is a truncated Poisson distribution, the size of the hypothetical population risking habu-bite was estimated by the maximum likelihood method. We obtained the value of 41993, which was approximately 35% of the total population and roughly equal to the size of the farming population. The incidence rate of habu-bite per unit of local population differed greatly according to the community unit (village, town or city), but the rates for the farming population and farming land did not differ greatly among the local communities. Patterns for the seasonal and diurnal distribution of habu-bite clearly indicated that the incidence of bites reflects the activities of both humans and habu.

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The increase of urinary δ-aminolevulinic acid in man and animals exposed to high concentration of mercury is studied, but the mechanism of the increase has not been clearly explained. In this paper, the content of 5β type steroid, inducing δ-aminolevulinic acid synthetase, was studied by noticing the activities of steroid 5β-reductase, which is the rate limiting enzyme in metabolism of steroid hormones, 3α- and 3β-hydroxysteroid dehydrogenase. For measurement of these activities, 105, 000×g supernatant of rat liver was used.
The testosterone and Δ⁴-androstene-3, 17-dione 5β-reductase activities decreased on either the fourth or eleventh day after either intraperitoneal or subcutaneous administration of mercuric acetate, respectively, and the adrenosterone 5β-reductase activity increased on the eleventh day after the subcutaneous administration of mercuric acetate. These changes mentioned above, however, were not significant.
The progesterone and 17α -hydroxy progesterone 5β-reductase activities decreased on either the fourth or eleventh day after either intraperitioneal or subcutaneous administration of mercuric acetate, but there were no significant changes. The Δ⁴-pregnen-20β-ol-3-one 5β-reductase activity decreased significantly on the fourth day after the intraperitoneal administration of mercuric acetate.
The 3α -hydroxysteroid dehydrogenase activity on etiocholanolone decreased significantly on the fourth day after the intraperitoneal administration of mercuric acetate, but that on androsterone and epipregnanolone did not show any significant change after administration of mercuric acetate. No significant change was observed in the 3β-hydrogysteroid dehydrogenase activity on epiandrosterone with the administration of mercuric acetate.
From these results, it was said that in mercury poisoning the increase of 5β type steroids was not verified and δ-aminolevulinic acid synthetase activity in heme synthesis was little affected by 5β type steroids.

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In this study we attempted to investigate the intrauterine growth curves in O. public hospital in Naha during the past ten years (1966-75), in comparison with those of A. private clinic in Naha and those reported in Japan and other various countries.
1) Although the obstetric service in O. hospital was established in November 1962, the birth records and the list of births with a sufficient description for this study are available since January 1966. The minimum unit of the balance used in its delivery room is 1 gram.
The number of single live births subjected to this study accounted for 6, 627 cases. The other 946 cases were excluded on account of the incomplete description on sex, parity, the commencing date of the L. M. P., or the estimated date of the delivery, and of multiple births, fetal deaths, early neonatal deaths or major congenital malformations (Table 1-2).
2) In the preliminary investigation it was found that the trends in the mean birth weigh increased significantly during this period (1966-75), and therefore we made three kinds of the intrauterine growth curves (1966-70, 1971-75 and 1966-75), by computing the mean, standard deviation, 10, 25, 50, 75 and 90 percentiles of the birth weight by sex, parity (primiparous and multiparous groups) and gestational age in weeks. The mean birth weights of 1971-75 is about 45-80 grams higher than those of 1966-70, especially between 38-43 gestational weeks (Fig. 2, Table 5).
3) The comparisons were made with the various intrauterine growth curves reported in Japan and from various countries (Table 11, Fig. 4). In comparison with the data of A. clinic in Naha during corresponding period, the intrauterine growth curves of O. hospital were about 50-60 grams lower at 39-40 gestational weeks. This was probably due to the differences in the distribution of the socio-economical classes of the mothers delivering in the two establishments in Naha. It is suggested that there may be some biases in the data Funakawa and Takano reported in 1976 (Ref. 4). In the international comparisons our data of the two establishments in Naha are situated between those in Taipei and in Great Britain, and is gradually approaching to that of Great Britain.
4) Based on these results we emphasized the importance, at first, of the random sampling for the preparation of the national standards of the intrauterine growth curves, taking into consideration the differences in the mean birth weight by area (at the regional and prefectural level) and by obstetric establishment; and secondly, of further investigations on the national and international comparisons of intrauterine growth curves in order to clarify the significance of the “birth weight” as a community health indicator in public health.

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For the purpose of studying the influence of air pollution that causes pulmonary tuberculosis, the authors investigated the relationship between the level of pollution by area in Yokkaichi on the one hand, and prevalence, incidence, the visit rate to the physician and death rate of pulmonary tuberculosis on the other hand.
Prevalence and incidence showed a similar pattern and were influenced greatly by economic factors of the area as observed in the relationship with the on-relief rate, but the influence of air pollution was not found under the level of the pollution as shown in Table 1.
The visit rate to the physician taken by those insured by the National Health Insurance Plan was influenced more or less by social factors such as the density of medical institutions and density of population in addition to the above-mentioned economic factor, but had nothing to do with the air pollution.
Death due to pulmonary tuberculosis was caused by sulphur dioxide; when the mean concentration for three consecutive days surpassed 60ppb, the probability of the death on the last day became higher, the differrence being statistically significant at 5 per cent compared with days on which the concentrations were 19ppb or less.

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This study was undertaken to investigate the level of basal metabolic rate (BMR) and its seasonal variation in people living in Okinawa. Determination of BMR was conducted in summer and winter during 1972 and 1973 on the same subjects consisting of 39 natives of Okinawa and 22 natives of the Japanese mainland. The results obtained were as follows:
1) It was observed that the skinfold thickness and fat tissue mass were lower in the subjects native of Okinawa than in those native of the Japanese mainland (Table 1, 2). Whereas, BMR in natives of Okinawa was almost the same as that in natives of the mainland, and both were compatible with the Japanese BMR standard reported by the Ministry of Health and Welfare (Fig. 1).
2) In agreement with the results of past experimental studies on Japanese, BMR of residents in Okinawa showed seasonal variations, being low in summer and high in winter (Fig. 1, Table 3). The mean variation rate of all the subjects in terms of the annual mean of BMR was 3.2%.
3) Seasonal variation rate was higher in office workers with uncomplete cooling system than in those who worked and lived in airconditioned rooms (Maritime Self-Defence Force personnel) or in those receiving hard physical training (Police school students). (Table 6).
4) The seasonal variation range of the outdoor temperature was about 27.99°C∼16.76°C in Okinawa and 27.16°C∼6.43°C in the Japanese mainland according to the data of the Weather Bureau. The seasonal variation range in the present study was compared to those obtained in mainland as follows;
From the results reported recently in Sasebo and Nagasaki, both in mainland, by Yosida and Chen, respectively, the variation range of BMR in two months with the temperature comparable to the summer mean (27°C)and the winter mean (17°C) in Okinawa, was calculated by the present auther as ±2.6% This figure is almost the same as the value of 3.2% in summer and winter for the residents in Okinawa, obtained by the author.
In view of the results of the present study, it is suggested that the range of seasonal variation of BMR for the Southwest Japanese people is controlled by the annual range of the outdoor temperature and their living environmental temperature, irrespective of Okinawa and the Japanese mainland.

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Granules of active carbon (average diameter 1mm) coated with silver, named silver carbon (SC), were examined regarding a decreasing fatal action of mouse hepatitis virus (MHV) to ICR mouse. It was performed by injecting into abdominal cavities of 3 ICR mice in each group with 0.2ml of a MHV infected liver suspension. The number of mice dying and an average period until death were noted. The results were as fellows.
(1) A suspension of mouse hepatitis virus (10^-6 or 10^-8 dilution) after shaking with 5g of SC or granules of active carbon not coated with silver (CC), reduced the number of mice dying in comparison with that using a suspension of MHV did not mix with SC or CC.
(2) A suspension of MHV filtrated through a filter layer of SC or CC (3g) in a glass column showed the same tendency as (1) toward ICR mouse. The effect of SC was excellent as compared with that of CC in some conditions.
(3) Filter layers made of SC of various weights (6, 9 or 12g) were examined for decreasing a fatal action of MHV to ICR mouse. The thickest filter layer of SC. (12g) was the most excellent to obtain the effect among the other 3 layers. Further examinations were required on that the effect of SC to MHV was reduced gradually, while the suspensions of MHV was filtrated continuously through the SC filter layer.

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In previous papers (Ref. 3, 4), it was reported that the maximum growth age in height (MGA) was influenced by great social changes. The percent of calories from starchy foods (PCSF), what is called “the second Engel's coefficent”, is generally considered to be the indicator not only of nutrition level but also of the level of living. The annual changes of MGA were compared with those of PCSF in Japan after World War II. The results were as follows:
1) Annual changes in PCSF as well as in MGA were found to be in agreement with Gompertz and logistic curves. Considering the similar tendency shown by the two, MGA may be considered to be a useful social indicator.
2) Time lag of 20 years was observed between inflexion points of regression curves of MGA and of PCSF. From this fact, it was considered that the changes of the nutrition level such as PCSF were not directly connected with the growth acceleration in height.
3) Annual changes in intakes of eggs, milk and milk products showed Gompertz or logistic curves inverse to that of MGA. However, just as seen in PCSF, time lags were observed between the inflexion points of regression curves of MGA and of eggs, milk and milk products intake: 17-18 years' lag in the case of eggs intake curve, and 22-23 years' lag in the case of milk and milk products intake. Accordingly, it was considered that eggs, milk and milk products intake were not directly connected with MGA.
From the above-mentioned considerations, it may be concluded that various social changes in Japan i.e., modernization, urbanization, industrialization and so on, have simultaneously influenced on and brought about the changes in the growth and dietary life of school children.

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