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41.
Inbred rabbits of B/Jas strain were found to be highly susceptible to herpes simplex virus type 1 encephalitis, following i.v. injection of the virus, while Chbb:HM strain rabbits were not susceptible. The susceptibility trait seemed to be inherited recessively, involving multiple genes, because (B/Jas x Chbb:HM)Fl hybrids were as resistant as Chbb:HM rabbits, and because more than 90% of backcrosses of (B/Jas x Chbb: HM)FI to B/Jas were resistant to viral inoculation. The encephalitis in B/Jas rabbits resembled human herpes simplex encephalitis, in that the temporal lobe as well as the brain stem were affected preferentially, leading to the development of various types of seizures, such as circling, loss of balance leading to a fall, and tonic and clonic convulsions. The disease could be diagnosed by magnetic resonance imaging (MRI) analysis before onset of seizures, and diseased rabbits showed a marked lymphopenia at onset of seizures. © 1995 Wiley-Liss, Inc.  相似文献   
42.
We have obtained the good result about tricuspid annular constriction (TAC) for secondary tricuspid insufficiency. The purpose of this study is to investigate the effectiveness of TAC for the experimental model of tricuspid annular dilatation. First of all, tricuspid annular dilatation was made surgically in 8 mongrel dogs by placing 8 incisions to tricuspid annulus except septal cusp under the condition of heart-lung preparation. On clinical evaluation, septal annulus was kept to be intact in many cases compared with the two other areas. This experimental model of tricuspid annular dilatation was considered to be substituted to the clinical model of tricuspid annular dilatation. TAC suture was surrounded circumferentially around the dilated tricuspid annulus. And then, TAC suture was pulled out from the right atrial wall, and the circumferential length of tricuspid annulus was completely accommodated by pulling the TAC suture. The hemodynamic status was observed by right atrial pressure (V wave and mean) and right ventricular end-diastolic pressure (RVEDP). After heart resuscitation and gradual increase of preload, right atrial pressure was significantly elevated especially right atrial pressure (V wave) compared with control values. When 2 cm of circumferential length of tricuspid annulus on an average was constricted by shortening of TAC suture, right atrial pressure was significantly decreased, and then RVEDP tended to decrease. It was shown that TAC was an effective operative technique for the secondary tricuspid annular dilatation and tricuspid insufficiency from the standpoint of experimental aspect as well as clinical results.  相似文献   
43.
There is a growing body of evidence that the cytokine, tumor necrosis factor-α (TNF-ga), plays an important role in the development of hepatic ischemia/reperfusion injury. We found that the immunosuppressants, cyclosporine-A (CsA), azathioprine, and FK506, have protective effects on such injury. The purpose of the present study was to elucidate mechanisms involved in these beneficial effects of the immunosuppressant, CsA, on liver injury following cold preservation and transplantation, with special reference to the suppression of TNF-α release. Rat livers were stored in Euro-Collins solution (EC) at 4°C for 6h and orthotopically transplanted. The animals allotted to two groups: group A (untreated controls) and group B (CsA pretreatment of recipients). CsA (10 mg/kg, p.o.) was given for 3 consecutive days preoperatively. CsA pretreatment of the recipients significantly improved the 2-week survival rate (0/6 for group A, 3/6 for group B;P<0.05) and this was associated with a significant decrease in serum TNF-α levels 2h posttransplantation (group A, 69.8±15.7 pg/ml; group B, 22.8±6.8; mean±SEM;n=12 each;P<0.05) and amelioration of sinusoidal endothelial injury, assessed by electron microscopy. Plasma endotoxin levels following reperfusion of the grafts were not altered by the CsA therapy. Morphologically, CsA pretreatment of the recipients did not alter activation of Kupffer cells. CsA pretreatment of the recipient aids in preventing cold preservation/reperfusion injury of the liver graft, possibly by modulating effects of TNF-α.  相似文献   
44.
We investigated the temporal and spatial expression of transforming growth factor-β in the healing patellar ligament of the rat by immunohistochemistry. The mid-portion of the medial half of the patellar ligament in 14-week-old male Wistar rats was cut transversely with a scalpel. On day 1 after ligament injury, diffuse staining for transforming growth factor-β was observed in the extracellular matrix filling the wound, and the staining in the adjacent ligament tissue was as weak as it was in the normal ligament. On day 3, the intensity of the diffuse extracellular staining decreased, and the staining was observed in correspondence with the cellular distribution in the wound site and in the adjacent uninjured ligament tissue. On day 7, the intense staining was widely distributed over the whole length of the ligament tissue. On day 28, the staining for transforming growth factor-β was still observed at the wound site and in the adjacent uninjured ligament tissue, where the staining was reduced in intensity but still stronger than it was in the normal ligament. On day 56, the expression of transforming growth factor-β was still detectable at the wound site: however, in the adjacent uninjured ligament tissue, it had almost subsided to the normal level. The results of the present study suggest that ligament healing may be accompanied by extensive changes in the expression of transforming growth factor-β over the whole length of ligament tissue.  相似文献   
45.
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   
46.
A 32-year-old man had been suffering from dyspnea on exertion and stridor, which were due to stenosis of the left main bronchus as a complication of bronchial tuberculosis. A three-connection stent, 1.2 cm in diameter and 4.5 cm in length was placed at the site of the bronchial stenosis. Dyspnea disappeared 2 days after the procedure, and the pulmonary function 3 weeks later showed considerable improvements in %FVC, FEV1 and MMF.  相似文献   
47.
A 68-year-old woman was admitted with cough and dyspnea. Her chest X-ray showed right pleural effusion and a mediastinal tumor. She underwent mediastinotomy following a preoperative diagnosis of invasive thymoma. A tumor originating from the thymus had invaded the right middle lobe and pericardium, and multiple pleural dissemination was also found. Therefore, considering the patient's age and pulmonary function, we performed only subtotal resection of the tumor. The pathological diagnosis was poorly differentiated squamous cell carcinoma. The patient received irradiation and chemotherapy including Cisplatin after surgery, but she died 1 year later because of rapid progression of distant metastases.  相似文献   
48.
Sodium valproate was administered to Jcl:ICR mice in order to evaluate teratogenicity in the cardiovascular system. A single dose of 600mg/kg of sodium valproate was injected intraperitoneally on gestational day 6, 7, 8 or 9. On day 18 of gestation, dams were laparotomized to observe incidence and type of cardiovascular abnormality in live fetuses. Cardiovascular abnormalities were found most frequently in the group treated on day 7, being recognized in 86% of litters (19/22) and in 29% of live fetuses (70/238). Among these, there were 28 cases of transposition of the great arteries, 13 of double outlet right ventricle, 11 of endocardial cushion defect, 9 of ventricular septal defect, 5 of tricuspid atresia, and 4 of hypoplastic left heart syndrome.  相似文献   
49.
Thymolipoma is a very rare mediastinal tumor. We reported a case of 52-year-old female with thymolipoma which was located in the cervicomediastinal area. The chest X-ray film revealed an abnormal shadow in the superior mediastinum. Computed Tomography (CT) clearly showed the existence of a large mass in the left side of the trachea. The angiogram showed that there was a stenosis on the left brachiocephalic vein. On June 13, 1988, median sternotomy was performed. A large tumor, about 5.5 x 13 x 5.5 cm, was found arising from the left cervical area. This tumor was excised completely and thymolipoma was diagnosed histopathologically. The post-operative course was very satisfactory.  相似文献   
50.
We report a case of an anterior interosseous nerve palsy after closed reduction and percutaneous pinning of open fractures of the radius and ulna in an adult. Operative findings showed that the anterior interosseous nerve was trapped between the distal and proximal part of the fractured radius. Treatment by neurorrhaphy gave a satisfactory result.  相似文献   
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