Effects of prostaglandin E₁ (PGE₁) on platelet function were investigated both in vitro and in vivo, and the following results were obtained :
1. PGE₁ was a powerfull inhibitor of in-vitro platelet aggregation induced by ADP, thrombin or collagen. The inhibitory effect of PGE₁ on ADP induced aggregation was 100-1, 000 times greater than that of adenosine.
2. Theophylline inhibited the platelet aggregation induced by ADP and enhanced the inhibitory effect of PGE₁. Exogeneous cyclic AMP also inhibited the ADP-and collagen induced aggregation. From these results, it was suggested that the effect of PGE₁ on platelets might be mediated by an increase in the amount of cyclic AMP in platelets.
3. PGE₁inhibited the release of platelet factor 3 or serotonin from platelets.
4. PGE₁ produced a similar shape change in platelets by ADP.
5. In experimental rabbits, PGE₁ also inhibited the in-vivo aggregation of platelets, although there was no effect on the formation rate of stasis thrombus in the jugular vein or thrombus formation on the femoral artery with stenosing ligature by ellagic acid.

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The effects of prostaglandin E₁ on coronary and systemic circulations were studied in anesthetized open chest dogs.
The prostagiandin E₁ showed a potent dilatatory effect on the coronary as well as the peripheral vessels. Following the intravenous injection, the aortic blood flow was markedly increased, while the aortic pressure was significantly decreased. The coronary blood flow was markedly increased following the intracoronary injection of the prostaglandin E₁. The increase in the diastolic coronary flow was more prominent than in the systolic coronary flow. Although the coronary blood flow was slightly increased immediately following the intravenous injection of the prostaglandin E₁, the flow returned soon to the control level as the aortic pressure was decreased.
A direct chronotropic effect of prostaglandin E₁ could not be demonstrated in the present study. The heart rate remained unchanged following the intracoronary injection, although a slight but significant increase in the heart rate was observed when the prostaglandin E₁ was injected intravenously.
It was postulated that a significant increase in maximum dp/dt of the left ventricle following the intracoronary injection of the prostaglandin E₁ might suggest the direct positive inotropic effect.

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This paper is concerned with the statistical studies on the 99 cases of the maternal death in Gunma prefecture during the period of 5 years (from 1965 to 1969).
Results were as follows :
1. The mean value of maternal mortality per year was 19.8 ± 5.54. More than 60% of total cases was observed in the group aged over 30, and the number of the cases in the group of ages over 35 years was unexpectedly high.
2. Concerning with the causes of death, when compared with those of previous study (from 1957 to 1960), toxaemia and bleeding were decreased, while those of postabortal death and others were increased. The number of death from infection and ectopia is not significantly changed. Over all the cases of maternal death were decreased in the prefecture.
3. As for the place of death, the number of the cases other than medical clinic was decreased. However, the cases of death in the group of home confinement were still observed in aged pregnancy, indicating the direction to be stressed in maternal and child health.
4. Little changes were observed in the rank order of the number of the cases in the district of each territorial health center when compared with that of previous study (from 1957 to 1960). No community in the prefecture had maternal death every year, and maximum number of occurrence of the case in one community was three throughout 5 years. There was no consistency in the occurrence of the case in any special district. The result might suggest that the maternal deaths in the prefecture were caused by some arbitrary factors.
5. In spite of above results, the data suggested the need of precaution for toxaemia in mountain area and some part of town area, and that for bleeding in the districts near border of the prefectures.
The results of the study indicate that the intensive precautions for the maternal death are still needed, especially for toxaemia and bleeding. The paper also emphasizes the need of emergency care system to reduce the maternal deaths in the prefecture.

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Clinical course of Hirschsprung's diasease (aganglionosis) is fairly variable depending upon its length of the aganglionic segment and accompanying enterocolitis. Cremin and co-workers subdivided it into five groups.
Case histories and x-ray findings of two cases of the long segment aganglionosis were presented. The first case showed rather typical x-ray findings and its diagnosis was readily established. A transverse colostomy was made successfully, but he died of a fulminant attack of enterocolitis about a year later. The second case had normal calibered aganglionic segment without showing irregular bizarre contraction. The site of caliber change was also not apparent, but there was a caliber difference between the ascending colon and the descending colon. The diagnosis was made as a stenosis in the splenic flexure and a side-to-side anastomosis between the dilated transverse colon and the collapsed sigmoid colon was carried out. His postoperative course was complicated with continuous vomiting, increasing abdominal distention, wound infection and entero-cutaneous fistulas. He succumed on 15th postoperative day. Autopsy revealed the long segment aganglionosis extending to the left half of the transverse colon.

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