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1.
We examined the effect of interruption of pulmonary arterial flow and inadequate ventilation on the development of pulmonary infarction in rats. Pulmonary arterial flow was blocked by the injection of agar into the inferior vena cava and inadequate ventilation was produced by obstructing the left main bronchus with a polypropylene tip. Histological and angiographic examination of the lung demonstrated that: pulmonary artery embolism alone does not induce pulmonary infarction; obstruction of a bronchus does not induce significant changes, but that pulmonary infarction develops when pulmonary artery embolism and obstruction of a bronchus occur simultaneously. It has been thought that pulmonary infarction is caused by acute obstruction of a pulmonary artery, however, the alveolar walls are supplied with oxygen by both the pulmonary circulation and by ventilation. Interruption of pulmonary arterial flow alone is probably not sufficient to induce pulmonary infarction, which is probably caused by deficiency of oxygen supply to the alveolar walls by a synergy between interruption of pulmonary arterial flow and inadequate ventilation.  相似文献   
2.
We previously reported that the Guardian Bio-Threat Alert (BTA) system could detect (detection limit: about 0.1 μg/ml) staphylococcal enterotoxin B (SEB), botulinum toxins (BTX) A and B, and ricin, with no interference by white-powdered materials or colored matrices. In this study, the capability of the BTA system was further assessed. With 10 min of preheating at 60°C, all toxins could be detected, but with preheating at 80°C, BTX A and B and ricin became undetectable. About 20% SEB could be detected after heating at 80°C, but this detection ability was completely removed after heating at 100°C. The effects of chemicals usually used for decontamination, such as sodium hypochlorite, hydrogen peroxide, formaldehyde, and sodium nitrite, on the detectability of SEB, BTX A, or ricin in the BTA system were also tested. The concentrations giving 50% line intensity for SEB, BTX A, and ricin were 3.1, 11, and 15 μM for sodium hypochlorite and 88, 210, and 60 mM for formaldehyde, respectively. The addition of hydrogen peroxide or sodium nitrite did not decrease the detectability even when used at high concentrations.  相似文献   
3.
BACKGROUND: Cytomegalovirus (CMV) diseases commonly occur in allograft recipients in the early post-transplant period. However, factors responsible for the high incidence of CMV diseases during this period are not yet fully defined. METHODS: Wistar-Furth (WF; RT-1(u)) rats were inoculated with 10(4) plaque-forming units (PFU) of rat CMV (RCMV) intraperitoneally, and then transplanted with allogeneic lungs from Dark Agouti (DA; RT-1avl) rats or stimulated with 10(7) mitomycin C-treated spleen cells from DA rats by daily sub-cutaneous injections for 2 weeks. No immunosuppressive agent was used. Naive WF rats and WF rats grafted with syngeneic lungs or cells were used as controls. The level of RCMV replication in rats was assessed by infectious virus titers in tissues. RESULTS: The virus titers in salivary glands of allogeneic and syngeneic lung graft recipients were significantly higher than in naive WF rats. The level of RCMV replication in rats stimulated with allogeneic spleen cells was significantly higher than in the syngeneic recipient rats: virus titers in the salivary gland of allogeneic and syngeneic recipients reached 4.61 +/- 0.33 and 4.00 +/- 0.37 log(10) PFU/g tissue, respectively, at 14 days post-infection (p = 0.015). The augmented viral replication in allogeneic recipients was confirmed by an increase in the number of RCMV antigen-positive macrophages present in tissue sections of the salivary gland. CONCLUSIONS: Acute lung allograft rejection and allogeneic spleen cell stimulation enhance CMV replication in the salivary gland of rats. Various responses to allogeneic antigens occurring in the process of acute allograft rejection could be risk factors for post-transplant CMV replication and infection.  相似文献   
4.
5.
Elderly onset rheumatoid arthritis (RA) is difficult to diagnose definitively when the patients note their first symptoms of arthritis above the age of 75 years old. In this report, we reviewed the clinical features of elderly onset RA and its diagnosis. The subjects included 4 females, aged 78, 83, 84 and 93 years, respectively. The onsets were abrupt in 2 cases and more slowly arriving in the other 2. Shoulder joints and wrist joints were involved in all cases. Knee joints, finger joints and foot joints were involved in 3 cases and the elbow was involved in one case. Anti-RA treatment quickly attenuated the acute and severe arthritis and brought down the high CRP level associated with vivid inflammatory activity of RA. The RAPA value was very high in all but one of the cases. Severe destructive findings in radiography was undetectable in the major joints (e.g. shoulder, hip and knee joints). Radiographic findings in wrist and finger joints were also very difficult to differentiate from arthrosis and osteoporosis. On the other hand, RA involvement in the cervical spine was certain in the radiographs; 1 case had anterior atlantoaxial subluxation and 2 cases had subaxial intervertebral erosion. Pathological radiographic findings in the cervical spine are useful for the diagnosis of elderly onset RA.  相似文献   
6.
201Tl myocardial SPECT was performed in cases of dilated cardiomyopathy and valvular heart disease with left ventricular eccentric hypertrophy, and the two groups were compared from the standpoint of the mechanism of onset of myocardial disorders. Significant coefficients of correlation were seen between the Tl score and LVDd (r = 0.792, r = 0.785) and Tl score and LVEF (r = -0.634, r = -0.555) in both dilated cardiomyopathy and valvular heart disease. In cases of valvular heart disease, significant correlation coefficients (r = -0.756, r = -0.720) between LVDd and r-WR (relative-washout rate), and Tl score and r-WR were observed, but no such correlation was seen in dilated cardiomyopathy. In valvular heart disease, a decrease in myocardial perfusion associated with enlargement of the left ventricle appeared, while in dilated cardiomyopathy, there was a marked decrease in LVEF in proportion to the thallium defect. Therefore, it was assumed that left ventricular wall disorders occur due to myocardial metabolic disorders and coronary microcirculation disorders.  相似文献   
7.
Hepatoblastoma is the most common malignant liver tumor in children. Recently, liver transplantation has been indicated for unresectable hepatoblastoma. We retrospectively reviewed 14 children with a diagnosis of hepatoblastoma who had undergone living-donor liver transplantation (LDLT) at Kyoto University Hospital. During the period from June 1990 to December 2004, 607 children underwent LDLT. Of these interventions, 2.3% were performed for hepatoblastoma. Based on radiological findings, the pre-treatment extent of disease (PRETEXT) grouping was used for pre-treatment staging of the tumor. There were grade III in seven patients and grade IV in seven patients. Thirteen patients received chemotherapy, and seven underwent hepatectomy 11 times. Immunosuppressive treatment consisted of tacrolimus monotherapy in 11 patients. Actuarial 1- and 5-year graft and patient survival rates were 78.6% and 65.5%. The poor prognostic factors were macroscopic venous invasion and extrahepatic involvement with 1-year and 5-year survival rates of 33.0% and 0%. Pediatric patients without these factors showed an acceptable 5-year survival rate of 90.9%. LDLT provides a valuable alternative with excellent results in children with hepatoblastoma because it allows optimal timing of the liver transplantation, given the absence of delay between the completion of chemotherapy and planned liver transplantation.  相似文献   
8.
Summary A case of multiple osteonecrosis including both shoulders, hips, and knee joints and the right fourth metatarsophalangeal joint is reported.  相似文献   
9.
This study examines the pulmonary hemodynamics during reimplantation and rejection following unilateral lung transplantation in dogs. Nineteen mongrel dogs were divided into three groups according to the method of treatment used: group 1 (n = 6) underwent modified autotransplantation of the left lung; group 2 (n = 6), allotransplantation without immunosuppression; and group 3 (n = 7), allotransplantation with immunosuppression. The pulmonary arterial blood flow and ventilation scores, assessed by chest X-rays, were measured for 2 weeks postoperatively. Pulmonary blood flow to the transplanted lung decreased slightly in group 1, whereas in group 2, it decreased sharply from the 3rd postoperative day (POD) and was almost completely absent by the 14th POD. In group 3, it decreased by 28% on the 1st POD but recovered gradually to 37% by the 14th POD. Ventilation scores were the same among the three groups on the 1st POD but in group 2, they decreased rapidly from the 3rd POD. This change correlated well with that of the pulmonary arterial (PA) flow, although the ventilation score changed after the PA flow did. In conclusion, rejection was reflected earlier and more distinctly by the changes in PA flow than by chest X-rays.  相似文献   
10.
Morphological alterations in the lungs of rats deficient in either or both of vitamin E and essential fatty acids were investigated after exposure to hyperoxia for 48h. In rats deficient in both vitamin E and essential fatty acids, there was damage to type-2 alveolar cells observed as swollen mitochondria and bleb formation in the cytoplasm. None of these changes was found in rats deficient in only one of these substances. Hyperoxia in rats deficient in both substance also caused destruction of the capillary endothelial cells and edema in the interstitium. The lungs of rats deficient in only one of the substances showed some edema in the capillary endothelial cells, but not destruction, and less interstitial edema. These findings suggest that simultaneous deficiency in vitamin E and essential fatty acids facilitates lung damage in rats exposed to hyperoxia.(Murakami R, Obara H, Momota T et al.: The effect of hyperoxia on the lungs of rats deficient in essential fatty acids. J Anesth 3: 149–154, 1989)  相似文献   
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