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The purpose of this research was to examine the distribution of the tooth size in a large sample. The objective teeth were the left upper and lower fourteen teeth except the third molar. The tooth size of 1,000 dental casts from the Japanese female orthodontic patients was measured. On each of them, a histogram and a set of statistics (mean, standard deviation, coefficient of variation, skewness, kurtosis, Geary value) are given in order to examine the distribution. The findings are as follows: 1) Each tooth may be classified into the following four types of distribution except the congenitally missing data. TYPE I: A normal distribution was observed in the upper and lower central incisors, the lower lateral incisor, the lower canine, the upper and lower first premolars, the upper second premolar, the upper and lower first molars and the lower second molar., Type Ii: A positively skewed distribution was observed in the lower second premolar. TYPE III: A negatively skewed and leptokurtic distribution was observed in the upper canine and the upper second molar. TYPE IV: An extremely negatively skewed and leptokurtic distribution was observed in upper lateral incisor. 2) With the four teeth which were classified into TYPE II, TYPE III and TYPE IV, the distribution of the lower second premolar was concluded to be of normal distribution by logarithmic transformation. The distribution of the upper canine and the upper second molar was judged to be of lognormal distribution and the upper lateral incisor also was judged to be of three parameter lognormal distribution and four parameter lognormal distribution. 3) The distribution of thirteen teeth except the upper lateral incisor was judged to be of normal distribution, by considering the congenitally missing data and the outlier in statistical data of the tooth.

Limiting reduction of boar sperm nuclei revealed that disulfide cross-links of the boar protamines complexed with DNA were classifiable into five groups from the differences in their sensitivity toward the reduction. A feature of cross-linkings in boar sperm chromatin and that of bull is discussed.

We established an enzyme labelled immunoassay for the determination of alpha 2 macroglobulin (alpha 2M). The assay range was from 2 to 140 ng/ml and the within-assay coefficient of variation (CV) were 5.2% at 31.2 ng/ml and 6.4% at 62.5 ng/ml. Between-day CV ranged from 6.9% to 15.4%. Using this method, alpha 2 M was determined in the bronchoalveolar lavage fluid (BALF) from patients with interstitial lung diseases. Those diseases were active and inactive sarcoidosis, hypersensitivity pneumonitis and idiopathic pulmonary fibrosis (IPF, including collagen disease). We divided the IPF patients into two groups, 'acute type' and 'chronic type', judging from the prognosis. alpha 2 M/Albumin ratio in BALF in the active sarcoidosis and acute type IPF groups is significantly higher than that in the inactive sarcoidosis and chronic type IPF. These findings suggest that alpha 2 M in BALF can be a sensitive marker of the interstitial lung disease.

The objective of this study was to investigate the stress distribution in the mandible induced by occlusal forces in a various different horizontal mandibular positions identified as neutroclusion, distoclusion, mesioclusion, and laterally shifted occlusion. A three dimensional Finite Element Method (3D-FEM) was applied to an artificial model of a simulated mandible constructed as a homogeneous, isotropic and elastic body. This model was divided into 480 elements with 785 nodes. The right and left heads of the mandibular condyles and the occlusal surfaces of the posterior teeth of the model were restrained. These restraints acted against the loading of the masticatory forces which consisted of a pair of masseter, temporal, and also the lateral and medial pterygoid muscles. The stress distributions analyzed by 3D-FEM were graphically demonstrated on a three dimensional display system. The data obtained were summarized as follows: I. Neutroclusion (1) Tensile stress appeared along the anterior border of the ramus, and compressive stress appeared along the angular portion of the ramus. (2) Compressive and tensile stress appeared on the external and the internal surfaces of the anterior portion of the mandibular body. II. Distoclusion and mesioclusion (1) As the position of the mandible was moved distally, the absolute values of the stress tended to increase on the same areas which is the external and the internal surfaces of the anterior portion of the mandibular body. (2) Compressive stress which appeared on the occlusal surfaces of the posterior teeth was very great in distoclusion. At the same time, the stress that appeared on the heads of the mandibular condyle was also great in mesioclusion. III. Right laterally shifted occlusion (1) Tensile stress appeared along the left sides of both of the left and right rami, and compressive stress appeared along the right side of both of the left and right rami. (2) A great amount of stress appeared on the left occlusal surfaces of the posterior teeth and on the left portion of the mandibular body. From these results, it was determined probably that the mandibular morphogenesis was influenced by a series of stress factors which were induced by the forces of the masticatory muscles.