ラット(ウイスター系,オス)を次のようにA(正常飼糧,正常水),B (PCB 200ppm飼糧,正常水),C (PCB 500ppm飼糧,正常水),D (PCB 500ppm飼糧,ABS 1,000ppm水),E(正常飼糧,ABS 1,000ppm水),の5群に分け6週間飼育し,その後取り出した肝臓の切片を用いて,コレステロールの酢酸からの合成,胆汁酸への分解及び燐脂質へのリノール酸の取り込みを調べた。またラットの血漿,赤血球,肝臓の脂質及び血漿中のアスコルビン酸を測定した。
PCBを投与したラットの肝臓では,酢酸からのコレステロール合成およびコレステロールの胆汁酸への分解が対照群に比べて低下していた。しかしPCB 500ppmの飼糧とABS 1,000ppmの水を投与された群でのコレステロールの胆汁酸への分解は対照群と有意差はなかった。リノール酸の燐脂質への取り込みは各群差はなかった。
PCB 200ppmの飼糧投与により,血漿コレステロール,肝臓コレステロール,肝臓トリグリセライド上昇し,PCB 500ppmの飼糧では血漿の遊離コレステロール,燐脂質もさらに上昇した。またPCBを投与されたラットでは,赤血球中の燐脂質の減少がみられ,コレステロールも減少したが対照群と有意差は示されなかった。さらにPCB投与群では対照群に比較して約3倍量の血漿アスコルビン酸が検出された。
ABSの影響については,それ単独では血漿,肝臓の各脂質に影響しなかったが,ABS 1,000ppmの水とPCB 500ppmの飼糧を同時に与えると,肝臓のコレステロール,燐脂質はPCB 500ppmの飼糧のみを与えたものより有意に増加した。またさらにABSの投与により,赤血球中のコレステロール,燐脂質の減少が観察された。

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In vibration disease there is the peripheral circulatory and neurological disorders of fingers. As one of the means to diagnose these disorders, vibratory sense threshold (VST) is measured.
This paper describes the difference of the VST between chain saw operators with and without vibration induced white finger (VWF), the change of the VST before and after immersion of the fingers in cold water at 10°C, and the relationship between the VST and skin temperature. The VST was measured on the right index and right middle fingers of 168 male chain saw operators for the test at frequencies of 100 and 200Hz.
The results were as follows:
1. The VST of four fingers (from index to little finger) individually and collectively was measured in 13 normal subjects. At a frequency of 100Hz, the VST in each finger was higher than that in collective four fingers, but at a frequency of 200Hz there was no difference of the VST between the two measurements.
2. The VST in the chain saw operators was higher than that in the normal subjects at frequencies of 100 and 200Hz. In the chain saw operators there was statistically significant difference of the VST between no VWF numbness group and the VWF group, or between the numbness group and the VWF group.
3. There was no statistically significant difference of the VST between index and middle fingers of the chain saw operators.
4. The VST increased with age.
5. The VST showed no change, while the experience with a chain saw prolonged.
6. The VST at a frequency of 200Hz became high, as the skin temperature became low.
7. The VST after immersion at the hand in cold water at 10°C in the VWF group was higher than that in the normal group.

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It is well known that most dust in the lecture room is chalk dust. Dust concentrations were measured at intervals of 3 minutes on a horizontal plane and a vertical plane, after wiping the blackboard for 20 seconds on which many letters were written. Also particle size distributions were measured. The state of dispersing and floating dust in the lecture room can therefore be determined. The results are discussed as a guide to the measurement of dust described in “Requirements for a healthful school environment”.
The following results were obtained:
1) The dust environment in the lecture room is separated into three sections by dust isoconcentration curves, that is, a position less than 2.5m distant from the blackboard shows the highest dust concentration, and a position farther than 5.0m distant from the blackboard shows the lowest dust concentration.
2) Each dust concentration appears similar to a damped oscillation decreasing during 7 to 8 minutes after wiping the blackboard. After this, the dust concentration does not change but shows the floating dust concentration.
3) The dust concentration at 10 minutes after wiping the blackboard is almost the same at all heights, but the farther the distance from the blackboard, the lower the concentration of dust.
4) All particle sizes of chalk dust are shown to be below 7.0μ diameter (by 1-b) and the greater part are below 5.0μ diameter (by 1-b). The proportion of particles below 0.9μ diameter (by 1-b) shows no change at distances farther than 4 to 5m from the blackboard.
5) In order to evaluate correctly the dust environment in the lecture room, dust concentrations should be measured at 10 minutes after wiping the blackboard. Measurements should be taken at more than three positions on the center line of the lecture room, including the teacher's desk, 2.5 to 5.0m distant and more than 5.0m from the blackboard.

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新潟市の1948∼1955年,および1963∼1970年の人口動態統計から,双胎出産頻度の季節的変動解析を行なった。
双胎出産頻度の季節的変動を受胎月でみると,気候の温和な春・秋に高く,stressfulな夏・冬に低い,年間二峰性の変化であった。
また,この両者の間には有意の差が認められた。
双胎出産頻度からみた双胎受胎率の季節的変動と,下垂体前葉ホルモン,とくにgonadotrophic hormoneの分泌量の季節的変動とは何らかの関係があると思われる。以上の点について,若干の考察を加えた。

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Presuming that records of absence in primary schools can be used for the evaluation of health state of a school child or a group of school children, records of absence from April 1971 to March 1972 on 3, 021 children in a school in Kyoto city and in two schools in the suburbs of Kyoto city were statistically analyzed. The following results were obtained.
The frequency distribution of the number of days of absence of each child during a year was positively skewed on both boys and girls in every grade and in every school. The arithmetic mean or the median of the distribution differed among grades, between boys and girls and among schools. The threshold number of days of absence during a year for the detection of vulnerable children was calculated from every grade.
The frequency distribution of absentees on each day fiitted well to the frequencies given by Poisson distribution in every grade and in every school when the observation was limited to the absence due to non-infectious diseases during one term. The upper limit of the normal range of the rate of absentees on one day was calculated for various average rates of absence.
Moreover, in order to look for the causes of daily variations of absentees, the difference of average absentees among days of week and the relation between the number of absentees one day and various meteorological conditions were investigated during the winter term.

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沖縄県の最近における平均出生時体重の推移を観察すると全国値と比較して絶対値は低いが,逆に年間増加率はかなり高いことが指摘されている。本論文ではこの現象をさらに詳しく検討する目的で那覇市内某医療機関における過去20年間(1955∼74年)の分娩記録延11,504例について,その中から必要事項に関する記載が不備のもの,複産,胎児死亡,早期新生児死亡,著しい先天奇型のあるものなどを除外した計9,080例を研究対象とし,男女,初産・経産および在胎週別に各年度および1957∼59年,1962∼64年,1967∼69年,1972∼74年の3年ごとの4時期について平均出生時体重とその標準偏差を算出して,これに検討を加えた。
その結果当該期間において男女,初産・経産とも在胎38∼41週あたりで平均出生時体重が著明に増加していることが確認された。考察においてこの出生時体重の増加現象が当該期間における沖縄県の社会生活環境条件の著しい改善・向上に起因するものであると推論した。

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