By recording the electrocardiogram and phonocardiogram simultaneously using three abbreviated leads, 23,216 (6 and 7 years of age) elementary school children were screened for heart diseases. One hundred and one cases (0.44%) with congenital heart diseases, ten cases (0.04%) with acquired heart diseases and 100 cases (0.43%) with electrocardiographic abnormalities were discovered. From these observations, we conclude that this screening method applied on school children is useful in discovering the previously unrecognized heart diseases, especially atrial septal defect, primary myocardial disease and arrhythmia.

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Flies from different geographical parts of Thailand were collected to study their medical importance as well as making a zoogeographical study. After examination, 32 species of 10 genera, Orthellza, Mitroplatia, Morellia, Pyrellia, Rypellia, Haematobia, Haematobosca, Stygeromyia, Haematostoma and Stomoxys, belonging to Muscidae were identified and these are reported in this paper. Some of these are newly recorded ones from this country. This study is based on the specimens available in the authors’ collection.

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After devising remote-controlled angle to gastrofiberscope in 1964, the authors invented a swan-type double bending gastrofiberscope in 1967. The double-bending gastrofiberscope does not require any change in a patient’s position, for the motion of the tip is sufficient to observe every part of the stomach on supine position. In order to relax the patient both physically and men tally, relaxation of the patient is obtained by taking off this excessive attention on the endoscopic examination. Clear visual field can be obtained at the moment when the fiberscope passes the cardia, by stopping the scope just above the cardia and inflating sufficient air, and then, inserting the scope with the lens directed to the anterior wall of the greater curvature. Several marks are put on the body of the scope, as a functional scale, which makes its handling easier.

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The effect of parathyroid hormone (PTH) on the spongiosa of the proximal tibia and the alveolar bone in immature rats was studied using a time marker by the injection of lead acetate. 1) When intact rats were fed on a low calcium diet, the promotion of the apposition of the alveolar bone and the longitudinal formation as well as the reso1ption of the spongiosa were observed, but no change was detected in the serum calcium level. The resorption was more remarkable than the formation. 2) By parathyroidectomy (PTX) or thyroparathyroidectomy (TPTX) the effect described in 1) disappeared completely, but there subsequently occurred a fall of the serum calcium level and a marked inhibition of the formation and resorption. The decrease in the appositional f01mation was stronger than in the longitudinal formation. 3) When PTH was injected into the rats having undergone PTX or TPTX, all of the effects in 2) were reversed with the recovery of the apposition being at an extremely high rate. All the foregoing results indicate that PTH has an evident anabolic action in addition to the action of increasing the bone resorption and that the sensitivity to PTH is stronger in the periosteal bone than in the spongiosa.

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The effect of parathyroid hormone (PTH) on the formation of the incisor in the rats was investigated using a time marker by the injection of lead acetate. 1) When intact immature rats were fed on a low calcium diet, the rate of the longitudinal and appositional formation of the incisal dentin was increased. 2) Both formations were inhibited by parathyroidectomy (PTX) or thyro-parathyroidectomy (TPTX), the inhibition being stronger in the appositional than in the longitudinal formation. The mechanism generating the characteristic responses (thin dentin and irregularity of dentin formation) which appeared after the operations was made clear. 3) All of the effects in 2) were reversed by the injection of PTH. However, the restoration in the appositional formation was faster in appearance and higher in rate than in the longitudinal formation. The results of 1) to 3) indicate that PTH has an anabolic effect on the hard tissues. 4) The sensitivity of the tissues to PTH varies according to their embryological origin.

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The effect of parathyroid hormone (PTH) on mineralization and matrix formation was studied on the incisal dentin of immature rats by using a time marker as well as the histochemical method. 1. When the hypersecretion of PTH was caused by a low calcium diet, mineralization and matrix formation were both accelerated. 2. Both mineralization and matrix formation were clearly inhibited by parathyroidectomy or thyro-parathyroidectomy which brought about a widening of the predentin (dentinoid) as a result of the conspicuous inhibition of mineralized matrix formation. The maturation of the matrix seemed to be inhibited also. 3. Demineralization was lower and slower in the labial than in the lingual dentin. 4. The inhibitory effect disappeared totally by the PTH injection, but the restoration of matrix formation was faster compared with that of mineralization. 5. The increase or decrease in mineralization did not necessarily occur in parallel with that in matrix formation. 6. Acid mucopolysaccharide formation in the dentin depended clearly on the quantity of PTH.

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Three types of implant were simulated by the two-dimensional finite element method using the mechanical properties of human mandible and implant material as input data. Type 1 was a blade implant, type 2 was blade implant with subperiosteal wings in buccolingual direction, and type 3 was subperiosteal implant with no blade. The effect of buccolingual subperiosteal wings in decreasing the stress concentration around the neck portion of the blade implant was investigated under three kinds of occlusal force. In conclusion, the greatest stress concentration was observed at the cortical bone around the neck portion of T-1 blade implant. It was effective in decreasing the stress concentration at this neck portion to change the implant design from T-1 to T-2 or T-3.

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The present study was an attempt to investigate the effects of colchicine on the ultrastructure of rat osteoblasts with special reference to the microtubular function in vivo. Rats were killed at intervals of 2, 4, 8, 12 and 24 hours after the colchicine injection (0.1mg per 100g of body weight, subcutaneously). At 2 and 4 hours after the injection, the secretory granules and small vesicles accumulated in the Golgi area of the osteoblasts. The dilated spherical cisterna of the rough endoplasmic reticulum and the large vacuoles appeared, being located in the periphery of the cell. Microtubules were rarely found in the cytoplasm. Small masses of microfilaments of 80 to 110 A in diameter were found also in the cytoplasm. According to the special staining for collagen, it was indicated that the contents of the secretory granules might be collagen-like materials. At 8 hours after the injection, the shape of the osteoblasts transformed to a round profile and the autophagic vacuoles increased in the cytoplasm. At 12 and 24 hours after the injection, the osteoblasts seemed to be destroyed by the breakdown of the plasma membrane and by the increase of the autophagic vacuoles. It is suggested that colchicine affects the secretory process of the bone matrix and the cytoskeletal system of the osteoblasts by interfering with the structure and the function of the microtubules and colchicine also interferes with the function of the plasma membrane followed by the destruction of the osteoblasts.

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