Seventeen goats were used and bodys measurements of the mandibles and lower teeth were taken and a macroscopic morphological observation was made. An examination from the comparative anatomical viewpoint with other mammals was then made. The results were as follows : 1. In the occlusal form, the lower molar teeth were selenodont teeth peculiar to herbiborous animals. The anterior teeth were present only in the mandible. Eight teeth with three incisors and a canine on each side were positioned in a fan-shape. 2. There were three pairs of the lower premolars. P_1 was already regressed and disappeared and P_2 was small showing a regressive tendency. More mesially positioned a premolar was, the smaller its size was ; P_4 was the largest followed by P_3 and P_4 in descending order. 3. There were three pairs of the lower molars. More mesially positioned a molar was, the smaller its size was ; M_3 was the largest followed by M_2 and M_1 in descending order. Especially, the mesiodistal diameter of M_3 was larger in comparison with those of M_1 and M_2. The number of cusps was four for M_1 and M_2 and five for M_3. 4. The length of the cheektooth row was 76.58mm. The ratio of the molar row to the premolar row was about 67 : 33. The former was twice as long as the latter. The diastema between the canine and second premolar was 46.87mm, which was nearly twice the length of the premolar row. 5. The coronid process was higher than the condylar process with the ratio of about 4 : 3. The mandibular notch index was 51.86 and the notch depth was deeper than that for carnivora. These findings differ among various mammals. The difference is attributable to the difference in their food habits. 6. The height of the mandibular body was the highest, 38.59mm, at M_3 positioned most posteriorly. The height became lower toward the anterior side. The height was 14.51mm at the mental foramen. 7. The index for the ramus of the mandible was 28.62, indicating that the height is comparatively greater as compared with the width of the ramus. 8. The index for the head of the mandible was 36.27, indicating that the head thickness is greater in comparison with its length. This form, long in the right and left directions, appears to be a suitable morphology for masticatory movement for herbivora. 9. There was one mental foramen positioned on the outer surface of the mandibular body between the canine and second premolar. Its diameter was 3.17mm. In the vertical direction, it was positioned slightly higher than the center of the mandibular body. 10. The mandible foramen was 11.35mm in diameter and was positioned lower than the center of the mandibular ramus and close to the base of the mandible.

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Ten extracted human teeth have been used to find the effect of the root canal filling treatment using TCM ang Obtura after ultrasonic root canal cleaning. The evaluation was made by observing the state of root canal obturation and gutta-percha arrival to the apical seat using radiography and scanning electron microscopy. According to the radiographic observation, the state of filling by the use of TCM was good in all cases in the middle of root ; at the apex and the apical third the state was good except one case each. The use of Obtura showed about the same results as TCM. With respect to the arrival of gutta-percha to the apical seat in the use of TCM, all cases were evaluated as Flush. In the use of Obtura, the reslts varied, such as Flush, Under and Over. According to the observation using SEM, the root canal filling by the use of TCM were good in the middle of the root, and at apical third and at apex the state of filling was good except one case each. In the use of Obtura, in the middle of root and at apical third the state of filling was good ; and at the root apex the root canal filling was good in 2 cases out of 5 and the other 3 cases were fair or poor.

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The peroxisomal core was rapidly isolated from rat liver and identified as uricase itself as follows. Rat liver peroxisomes were broken by pyrophosphate treatment or sonication followed by sucrose-density gradient centrifugation. In each case, the cores with uricase activity and without catalase activity were recovered in the bottom frcations. Sodium dodecyl sulfate polyacrylamide gel electrophoresis of the cores yielded a single protein band in each case. These data show that the peroxisomal core is uricase itself in rat liver. This rapid isolation method of the peroxisomal core would be also usable for other mammalian.

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The acute toxicity of glutaraldehyde (G) was compared with that of formaldehyde (F) in ddY strain male mice, weighing 18-22g. After 25% G and formalin (about 37% F solution) diluted in olive oil were separately administered orally at the dose level of 0.1 ml/10g body weight, toxic symptoms and an increase of body weight of the survivors were observed and the number of deaths was recorded for 7 days. In each case, LD_<50> with 95% confidence limits was calculated by the Litchfield-Wilcoxon's method. The results were as follows : (1) Formalin presented more serious symptoms of the acute toxicity than 25% G. (2) Restraint of the growth was observed in all the survivors after the administration of 25% G and formalin, and this tendency was more remarkable in the mice administered 25% G. (3) The oral LD_<50> was 1300 (1090-1550) mg/kg and 660 (550-790) mg/kg for 25% G and formalin, respectively. (4) Since methyl alcohol is added in formalin to prevent polymerization, it is considered that the acute toxicity of G is roughly equal to that of F.

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Lactate dehydrogenase activity was detected in the lysosome-enriched fraction of chicken liver by the differential centrifugation method. By Metrizamide density gradient centrifugation, the half of the activity in this fraction was recovered in the lysosomal fraction free from peroxisomes and mitochondria. The enzyme activity in the isolated lysosomes was solubilized by Triton X-100 but scarecely by KCl. The solubilized profile of the enzyme from the isolated lysosomes by digitonin was nearly identical to that of acid phosphatase. The isolated lysosomes contained all of five lactate dehydrogenase isoenzymes. These results suggest that lactate dehydrogenase is located in the lysosomes and the cytosolic isoenzymes were uptaken by the lysosomes.

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In 1980, prevalence of dental caries and gingivitis, and oral hygiene condition were surveyed in 194 Yami children (107 boys and 87 girls) between 10 and 15 years of age. The mean number of DMF teeth was 1.43 (boys) and 1.67 (girls) in the 10-to 11-year-olds. The number increased with age and reached 2.85 (boys) and 3.55 (girls) in the 14- to 15-year-olds. However, the DMF score in Yami children was lower than that in Japanese children. The Yami children had extremely high OHI values (2.86-4.60), and the fact revealed that a half of every tooth surface was covered with dental plaque. PMA Index of Yami children was 3.67 (12- to 13-year-old girls) to 10.90 (14- to 15-year-old boys). These findings indicate that the dental plaque in the Yami children may be injurious to their gingival tissue but low in caries activity to their teeth.

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Anatomy of the tongue and floor of the mouth is readily discernible by ultrasound (US). This report describes a new method of monitoring movements of the tongue and the hyoid bone in three dimentions with a B-mode ultrasonographic transducer. Ultrasonographic examinations of masses in the oral cavity and the floor of the mouth can be a valuable diagnostic aid. It has the advantages of being noninvasive, rapid, easily repeated and relatively inexpensive. This tool may take the place of X-ray cinematography.

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