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21.
Transrectal hyperthermia was performed on 30 patients with benign prostatic hyperplasia twice a week for a total of ten times with the temperature of the prostatic tissue set at 43.0 degrees C. In our in vitro experiment using an agar phantom, the highest temperature was observed at approx. 1.5 cm from the point where the 915-MHz microwave was generated. Our histopathological study of the prostatic tissue, resected at open surgery after three days of hyperthermia, indicated that the effect of hyperthermia first occurred in the interstitial tissues, and then extended to the epithelial cells. Subjective symptoms and objective findings were evaluated. In almost all cases, improvement was observed in subjective symptoms after completion of the treatment. The residual urine volume improved significantly. Also, significant improvement was observed in our urodynamics study. In 16 out of 30 cases (53%), both subjective symptoms and objective findings were still improved after six months.  相似文献   
22.
Endoscopic placement of metal stents are used widely for patients with esophageal obstruction and fistula due to progressive esophageal cancer, but cause high rate of severe complications associated with the immediate causes of death. To determine severe complications caused by stents, we studied clinical data and autopsy of six patients who had been treated with stents for inoperable progressive esophageal cancer. Occording to the clinical records only two patients had severe complications due to stents. But at autopsy, three patients had massive hemorrhage in the stent placement, one patient had mediastinitis, and one patient were in imminent danger of perforation whose stent had been incorporated into the adventitia of the wall. More severe complications were revealed than those expected clinically. Endoscopic placement of metal stents have a great deal for the improvement of quality of life. But we should carefully decide the indication because endoscopic placement of metal stents could cause severe complications associated with the immediate causes of death.  相似文献   
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Leukotriene B4 (LTB4) production in polymorphonuclear leucocytes (PMN) was examined in ten children with steroid-responsive nephrotic syndrome (SRNS) before, during, and after steroid administration. Comparison of LTB4 production was made in 14 children with non-inflammatory disease who were not receiving steroid therapy. No significant change was noted in PMN LTB4 biosynthesis in children with SRNS throughout any phase of the disease. Furthermore, there was no significant difference in LTB4 biosynthesis in PMN between SRNS patients before steroid therapy and patients with non-inflammatory disease. These findings suggest that inhibition of LTB4 production is not involved in the mechanism underlying steroid action in SRNS.  相似文献   
25.
The reductive retention of62Cu-PTSM was comparatively studied in the brain and Ehrlich ascites tumor cells by electron spin resonance spectrometry and nonradioactive Cu-PTSM. In the brain, only the mitochondrial fraction showed the ability to reduce Cu-PTSM, and the other subcellular fractions did not. In contrast, the cytosolic fraction of Ehrlich ascites tumor cells was the specific site of Cu-PTSM reduction. It was therefore considered that the retention of Cu-PTSM in the brain is closely related to mitochondrial reduction, most probably involving the mitochondrial electron transport system.  相似文献   
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Many reports about the increase of renal cell carcinoma patients have been published in Japan recently, however, the real fluctuations in the total number of patients in relation to the change of population have not been reported yet. Most of the patients with renal cell carcinoma in the last 10 years were examined in Chiba prefecture, which has a population of about five million and 25 active urological offices. Histologically confirmed cases were investigated by sending questionnaire letters. The items were as follows; sex, age, address, occupation, family history, past history, symptoms, examination methods that first detected the tumor, operation date, tumor diameter and clinical stage. Twenty two offices returned answers and 560 cases who lived in Chiba were found to have renal cell carcinoma from 1980 to 1989. Yearly incidence rates per 100,000 persons demonstrated a significant increase from 0.32 to 2.07. Small, asymptomatic and low stage cancers have been increasing rapidly, however, the rate of metastatic disease has not shown any decrease. The main cause of rapid increase seems to be attributed to progress in diagnostic methods and increase of early detection, but the possibility of an increase in some carcinogenic factors can not be ruled out.  相似文献   
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We have already developed an arterial thrombosis model in the rat femoral artery which utilized photochemical reaction between systemically injected rose bengal and transillumination of a green light with 540 nm wave length from the outside of the vessel. In the present study, we applied this model to guinea-pigs in order to produce a more suitable thrombus model for evaluation of antithrombotic drugs which act on the prostaglandin cascade. In the guinea-pigs, the irradiated femoral artery was completely occluded in 7 min after the injection of rose bengal (10 mg/kg) in a similar manner to the rats. The processes of primary endothelial injury and the subsequent formation of thrombus during this manipulation were observed by the electron microscopy. Pretreatment with aspirin and Y-20811, a thromboxane synthetase inhibitor, significantly prolonged the time required for occlusion in the guinea-pigs, while these drugs were ineffective in the rats. The antithrombotic effect of vapiprost, a thromboxane A2 receptor antagonist, was more pronounced in the guinea-pigs than the rats. In conclusion, this model in guinea-pigs is more suitable for evaluating antithrombotic drugs, particularly, the action of which is exerted involving the prostaglandin cascade.  相似文献   
30.
The purpose of this communication was to find out the factors influencing the late patency ratio of coronary artery bypass grafts of 42 patients in our institution. The following results were obtained: 1. The size of the measured diameters of coronary arteries and the graft flow rates were correlated well to the late patency ratio (p less than 0.05). 2. The regular physical exercise trainings were significantly important to keep patent grafts (p less than 0.01). 3. In blood serum studies, serum uric acid levels were significantly lower (p less than 0.05), the average mean HDL cholesterol levels were much higher (p less than 0.001) and the ratio of total cholesterol to HDL cholesterol were significantly lower in the group with late patent grafts than with grafts occluded. Therefore, we found out the variables affecting graft patency ratio which were examined by a stepwise method were the diameter of the coronary artery, regular physical exercise training, the average of lower serum uric acid levels and higher HDL cholesterol levels. The multiple coefficient for these four variables was 0.562 (p less than 0.001) and the contribution was 31.6%. According to the base of this studies, we have concluded that postoperative regular physical exercise, low fat and restricted calorie intake were very important to keep the late patent grafts in long-term follow up period after coronary bypass surgery.  相似文献   
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