The influence of daily physical exercise on oxygen utilizing capacity of working muscle investigated by means of measureing lactate threshold (LT) during progressive treadmill running from the comparison between soccer group (S group: N=12, 11.9±0.1 years of age) and control group (C group ; N=14, 11.8±0.1 years of age) . LT₁ was determined as the point where blood lactate concentration (La) increased from rest level, and LT₂ was determined by the gradient, La/VO₂. body weight^-1 (2 mM/10 ml. kg^-1, min^-1) .
LT₁ and LT₂ in S group were significantly higher than those in C group expressed with absolute and relative values of VO₂ (1. min^-1, ml. kg^-1. min^-1, % VO₂max) . No significant differences in La, ventilation responses, and heart rate at the point of LT₁ and LT₂ were observed between S and C group, La showed slight decrease and was kept at lower level in S group with increase of VO₂, compared with C group. On the contrary, La in C group began to increase at lower level of VO₂. From our previous longitudinal study of LT in non-athletic children, we observed that LT shifted to lower level with growth. It was sugesed that La curve of S group, such shift had not occurred. Differences of these patterns in VO₂ and La between athletic children and non-athletic children were similar to those observed in adults athletes and non-athletes.
In conclusion it was supposed that sufficient daily physical training in 10-12 year of age might increase oxygen utilizing capacity of leg working muscle during running exercise.

Patient 1 was a 62-year-old woman who had been treated for hypertension for three years. Stanford A type acute aortic dissection occurred accompanied by right coronary ischemia. CABG and graft replacement of the ascending aorta were performed 8 hours after the onset of coronary ischemia, but after cardiopulmonary bypass the patient could not be weaned from the RVAD because of right ventricular infarction. On the 8th day after operation, she died due to right heart failure. Patient 2 was a 72-year-old male. Stanford A acute aortic dissection occurred and right coronary ischemia appeared during UCG examination in the ICU. CABG and graft replacement of the ascending aorta and the aortic arch were carried out less than 1 hour from the onset of coronary ischemia. The postoperative course was satisfactory and uncomplicated. If the dissection extends to the aortic root, it is important to monitor the ECG carefully to detect myocardial ischemic changes. In cases with coronary ischemia, early operation and CABG are mandatory.

A 47-year-old woman complained of dyspnea on exertion. Ultrasonic cardiography revealed coronary sinus type atrial septal defect. At operation, the drainage veins to the left atrium from the coronary arteries were observed but no anomalies of the vena cave or any other veins were observed. The defect was closed with a pericardial patch under cardiopulmonary bypass. The post-operative course was uneventful. Coronary arteriography performed on the 14th post operative day confirmed that the coronary veins drained individually into the corresponding atria. Unroofed coronary sinus is rare and difficult to diagnose prior to operation. Ultrasonic cardiography and coronary arteriography are considered useful for preoperative diagnosis.

We investigated sports disorders in 112 (82 men, 30 women) members of Field and Track Club, University of Tsukuba.
Before acupuncture treatment, they entered their painful and fatigued areas in our chart and were tested by Cornel Medical Index.
After six months, we questioned 51 (38 men, 13 women) members treated by acupuncture on effects.
The following results were obtained.
1. The painful areas varied with athletic events, that were muscles and joints they moved frequently.
The painful areas were mostly low backs and thighs in a short distance and hurdle race, hips and legs in a middle and long distance, low backs and legs in a jumping event, elbows and low backs in a throwing event.
2. As a result of Cornel Medical Index, it was proved that many members had more mental than physical symptoms.
3. Most of members treated by acupuncture could still go on with training in spite of pains.
4. The effects of treatment continued for 2-3 days.
5. The effects were rated as follows: better 78.4%, no change 14%, worse 6%.

The relationships between running performances (200 m running time and 5-min run) and VO₂max, Lactate Threshold (LT), or percent fat were investigated on 11-12-year old boys. Subjects were 21 control boys (group C) and 21 soccer boys (group S) . Mean 200 m running time in group S was significantly better than that in group C. Mean distance of 5-min run in group S was significantly longer than that in group C. No significant difference was found between mean running speed of 5-min run and mean speed at exhaustion in LT experiment. In group C, 200 m running time correlated significantly with VO₂max. In group S, faster runners showed higher peak post 200 m run lactate concentration. 5-min run correlated significantly with VO₂max for group C, group S and all subjects combined. LT correlated significantly with 200 m running time and 5-min run. No significant relation was found between running petformances and percent fat. It is suggested that VO₂max and LT determine, in part, boy's running performances, but percent fat do not.

The patient was a 52-year-old man with a history of antiphospholipid syndrome (APS), renal dysfunction and myasthenia gravis (MG). On May 2, 1998, he had sudden chest pain while sleeping. Enhanced computed tomography revealed acute aortic dissection (DeBakey type I). We performed emergency graft replacement of the ascending aorta and the aortic arch under extracorporeal circulation. Because of perioperative anuria, we used peritoneal dialysis (PD) just after the operation. Two days after the operation, we performed re-intubation nine hours after the extubation of the tracheal tube, and performed re-extubation three days later. For a while, his postoperative course was uneventful, but because of gradual worsening of APS, we administered more prednisolone, but 74 days after the operation, he died of multiple organ failure caused by an opportunistic infection, sepsis, and disseminated intravascular coagulation. This was very rare case of acute aortic dissection with MG and APS. After administration of more glucocorticoids, it is important to be wary of opportunistic infections.

The patient was a 63-year-old man with a history of multiple mononeuritis with hypergammaglobulinemia since 1980. The symptoms gradually worsened, and he had been bed-ridden since 1992. On February 28, 1997, he had sudden dyspnea after defecation. Echocardiography demonstrated a large thrombus in the right atrium and the right ventricle. Enhanced chest computed tomography revealed thrombi in the bilateral pulmonary arteries. The patient was considered to have acute pulmonary thromboembolism, and an emergency operation was indicated. Thrombectomy was performed under extracorporeal circulation through a median sternotomy. No thrombi were found in the right atrium or the right ventricle, and thrombi in the bilateral pulmonary arteries were removed completely. Four days after the operation, a Greenfield filter was implanted in the vena cava inferior because venography detected a thrombus in the right common iliac vein. The postoperative course was uneventful. No pulmonary rethromboembolisms were noticed after the operation. The long duration of being bed-ridden seemed to be the chief cause of thrombosis in the deep veins, and hyperviscosity due to hypergammaglobulinemia may have caused hyperthrombogenicity.

We evaluated bedside learning in the department of pediatric surgery by conducting a questionnaire survey of senior medical students at Chiba University School of Medicine. We obtained responses from 70 of 95 students (74%). Although 84% of students responded by making lists of patients' problems. Many students indicated insufficient knowledge about diseases and insufficient technical skills for medical treatment as the reasons they could not solve these problems. This finding indicates that students do not have sufficient basic knowledge and clinical skills for bedside learning. These skills must be acquired and evaluated before bedside learning can be started.