On the development of mammalian diaphragm it is generally accepted that the muscle of diaphragm was derived from lower cervical myotomes. In the recent, however, it was described on the diaphragm of xenopus, which was consisted of pars ventralis and pars dorsalis, that the latter one was derived developmentally from the mesoderms of forelimb bud.
To compare the origin and migration of muscle of mammalian diaphragm with those of xenopus, the author has investigated the development of mouse diaphragm by means of light and electron microscopy on the embryos aged from 9.25 through 12.5 gestational days. The graphic reconstructions traced from photomicrographs taking from the tinctorially examined serial sections are available for the present study.
From these observations the following results are obtained;
1) The most part of diaphragmatic premuscle mass arises from the ventral edges of 4th and 5th cervical myotomes at early limb bud period (9.75-10.25 gestational days), and secondarily it migrates ventrolaterally toward the dorsal part of transverse septum during at early to late limb bud periods (9.75-11.5 g.d.).
2) Only at the late limb bud period (10.5-11.5 g.d.) the diaphragmatic premuscle mass, which was just mentioned in 1), comes into contacts with the proximal border of the mesoderms of forelimb bud, and it appears that the former premuscle mass has received some part of the latter mesoderms during this period. With further development, the diaphragmatic premuscle mass after receiving some part of mesoderms from forelimb bud has migrated far ventral to the transverse septum; thus the contribution of the mesoderm of forelimb bud to the development of diaphragm has been demonstrated in mouse embryos as in xenopus.
3) During the process of migrations, the diaphragmatic premuscle mass has mainly consisted of presumptive myoblasts which were characterised by its spindle shapes and numerous free ribosomes with no detectable myofibrils in their cytoplasms.
Appearance of myoblasts containing myofibrils is proven in the transverse septum firstly at the later stage (12.5 g.d.) when the premuscle mass has arrived its definitive sites.

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In view of the complicated manner of growth hormone secretion we tried to observe changes in the secretion profiles as well as GH, thyrotropin and corticosterone in the plasma from normal and thyroidectomized rats, which were obtained not in a single but sequential blood collections. These fluctuations date were analyzed by power spectral analysis.
The most conspicuous change after thyroidectomy was a decrease in pituitary growth hormone contents. Pulsatile GH secretions were observed every 2.3 or 3.5 hr in normal rats, while thyroidectomy 3 weeks prior to experiments abolished the growth hormone burst. Corticosterone profiles from normal rats showed also pulsatile fashions which were more often observed in the night-time experiment. The episodic secretion of corticosterone seemed to inhibit the following growth hormone burst but not vice versa. Interrelation between integrated concentrations of growth hormone and corticosterone showed a negative correlation although the coefficient was not statistically significant. After thyroidectomy, the basal level of corticosterone decreased and the pulsatile secretion was blunched. There was no nyctohemeral variation in plasma thyrotropin level in normal rats except small and slow fluctuations. Thyroidectomy caused about ten times elevation in basal thyrotropin level.
Power spectral analysis revealed that small components in growth hormone secretion in normal rats, which had period of 60, 40, and 36 min beside the hormone burst. The spectral analysis also made it clear that there were small and frequent components (40 or 36 min periods) in corticosterone secretion.
By being expressed as the percentage of total power of each secretion profiles in the day experiments, the percentage of total variance accounted for by each period of interest can be directly estimated. With this management, it is suggested that these three hormones have the same spectral patterns on the episodic secretion profiles. Moreover, the effect of thyroidectomy on the spectral patterns was similar between these hormones.
It is indicated that retarded growth in hypothyroid rats is due to decreased integration of the growth hormone secretion.

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An autopsy case of volcanic H₂S intoxication was reported in a 39 year-old man, who had inhaled volcanic gases to fall into coma and died 7 days after his accident. Autopsy disclosed local irritation signs on the menbranes of the eyes and the respiratory tract. The conjunctiva and cornea were strongly injected. The tracheobronchial tree was found also congested and containing mucopurulent exudate. The lungs showed slight congestion and edema. Multiple acute ulcers were found.in the stomach and duodenum. The other organs were not remarkable. Microscopic examinations of sections of the brain and spinal cord revealed diffuse loss and degeneration of nerve cells. They showed the picture typical of ischemic, homogeniging, or Nissle's acute and severe degeneration. The regions especially affected were the cerebral cortex, thalamus, Purkinje cells of the cerebellum, cranial nerve nuclei and anterior horn cells of the spinal cord. In the cerebral cortex the change were found almost confined in the 3rd layer. An associated gliomesenchymal reaction was generally not conspicuous. Examinations of sections of the other organs and tissues disclosed multifocal areas of necrosis of the myocardium, degeneration of skeletal muscle fibers and marked fatty changes of the liver.
It is considered that changes in the nervous systems, heart, skeletal muscle and the liver were caused by respiratory failure with consequent asphyxia and anoxemia following exposure to volcanic gases with high concentrations of H₂S.

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There were 115 cases which were performed surgical treatment at the department of thoracic surgery, Gunma Cancer Center Hospital in the past 3 years from 1974 to 1976. These 115 cases consisted of 41 cases (37.5%) of lung cancer, 28 cases (24.3 %) of pulmonary tuberculosis and 19 cases (16.5%) of mediastinal tumor.
From 1974, we applied the mass survey technic to detect lung cancer and 78 cases of lung cancer were detected in this 3 years from 485, 145 inhabitants' X-ray films in the east district of Gunma. The incidence of lung cancer occurence for a population of 100, 000 in this district was 17. On the other hand, lung cancer detected in the outpatients was 99 cases.
In these 177 cases of lung cancer, the resected cases were 30 (16.9%) and 21 cases were in the mass survey, and 9 cases were in the outpatients. The incidence of lung resection was 26.9%, and 9.1%, respectively. In the resected cases, the survival rate over 3 years was 73.3% in the mass survey, and 50%, in the outpatients.
These data suggested that the mass survey was useful to detect lung cancer in its early stage.

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Sodium lactate in water solution is almost fully ionized above pH of 7.0 unit, however, it is ionized only 70% in lactate-ringer (Hartmann's) solution at the pH of 7.4 unit being calculated by conduction-metry in vitro in temperature range between 25°C and 37°C.
This depressed ionization of sodium lactate is caused by sodium ion's interference of coexisted strong electrolytes, saline. Partly an unexpected hypotonicity of lactate-ringer is due to this reduced ionization of sodium lactate. As plasma and extracellular fluid composed by a higher concentration of sodium chloride than that in Hartmann's solution, sodium lactate molecule will invade into cellular compartment in vivo more than 30% of its contents.
It causes a retension of free water when secretion of ADH, antidiuretic hormone, is increased. This fact may explain that hypertonic lactated ringer, HLS, is advantageous with cardiopulmonary resuscitation in severely burned victims.

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