Detection of various antigens was performed on the formalin-fixed, paraffin-embedded sections by indirect peroxidase-labelled antibody technique after pretreatment with trypsin digestion. It was revealed that the optimal condition for trypsin digestion of the paraffin sections differed according to the character of antigen and type of tissue, and, under the optimal condition, this method was easily applicable to the regular paraffin sections obtained in the laboratories for routine examinations. This method was also recommended for the detection of the antigens which were usually stained even without trypsin digestion, since it could not only remove the background staining but also uncover the otherwise masked antigen.
The change of the dentinal tubules by acid-etching and the morphology and the adhering state of new adhesive composite resin tags penetrating the tubules were obse1ved by SEM, comparing with the representative conventional composite resin.
When the fractured surfaces of the unetched floor dentin were observed, all tubule entrances were closed by blocking with cutting debris up to 10 to 20 µm depth. Etching opened them by dissolving the debris and further widened the tubule entrances up to 10 to 20 µm depth by dissolving the peritubular dentin near the apertures.
Resin tags penetrated 10 to 20 µm in vital teeth, 60 to 100 µm in freshly extracted teeth and several hundred µm in old extracted teeth.
The tags of the new resin penetrating the tubules copied exactly the shape of the tubule walls, producing hollow depressions at the ends, indicating that the resin polymerized, adhering tightly to the walls, while those of the conventional resin produced highly tapered side walls with pointed ends, indicating that the resin shrank separating from the tubule walls on polymerization.
The new resin did not produce any gap at the resin-dentin interface unlike the conventional resm.
The IP-Checker type MS capable of measuring the height of a crown at the intercuspal position (IP) was invented. The following observations were obtained.
1. The intercuspal position is stable within 5 µm
2. The intercuspal position shows a higher stability under slight biting than under heavy biting Under this condition, the teeth show a displacement of about 20 µm by the distortion of the periodontal membrane.
3. The crown made by the ordinary procedure is about 300 µm higher at the intercuspal position. Therefore, an occulusal adjustment is always necessary.
4. With the current method of occlusal adjustment adjustment of the crown to a definite height with the maximum error of 10 µm is possible in the oral cavity.
Surgical materials of gastric carcinoma were studied immunohistochemically in terms of the distribution of immunoglobulin-containing cells and the localization of secretory component (SC).
There was no convincing evidence suggesting that the secretory immune system surrounding carcinoma was responding to the carcinoma. But in some cases, increase of IgG-containing cells was observed in the stroma of carcinoma suggesting the presence of some kind of tumor immunity.
In the non-carcinomatous mucosa, SC was observed strongly in cells of intestinal metaplasia except for the goblet cells, but weakly in the normal foveolar epithelium.
The presence of SC in carcinoma cells was observed in 45 percent of the total cases of gastric carcinoma [36/80] and was especially porminent in signet-ring cell carcinoma [78%]. IgA was observed in about 50 percent of these SC-positive carcinoma cases. SC was also frequently positive in group III atypical epithelium.