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11.
We compared the antitumour effects of glycosylated LT (gLT), nonglycosylated LT and TNF against a solid tumour in mice. We found that: (a) The systemic administration of gLT showed significant antitumour activity. These effects were, however, quite small in nude mice. Nonglycosylated LT and TNF attained the same degree of effectiveness as gLT, but at a 5-times higher dose. The serum half-life of gLT was 3-fold longer than that of nonglycosylated LT and 22-fold longer than that of TNF. (b) The effect of gLT was significantly blocked by pretreatment with anti-asialo GM1 antibody. Treatment with gLT produced a significant reduction in numbers of tumour-regional mononuclear cells, which in turn, produced increases intensive necrosis. (c) Mononuclear cells in the tumour tissues before gLT-injection were predominantly IL-2 receptor +/CD3- cells and CD3+ cells. Pretreatment with the anti-asialo GM1 antibody produced a drastic reduction of IL-2 receptor +/CD3- cells. These findings suggest that the efficient antitumour effect of gLT is due to a longer serum half-life than that of nonglycosylated LT or TNF in vivo, and its function is largely mediated by IL-2 receptor +/CD3- cells.  相似文献   
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13.
Surgical technique of experimental lung transplantation in rabbits.   总被引:1,自引:0,他引:1  
BACKGROUND: Although rabbits have often been used as an experimental model for the analysis of lung preservation, there are no reports of long-term survival after rabbit lung allotransplantation. The purpose of this study was to establish a lung allotransplantation model for the evaluation of acute lung rejection in the rabbit and to investigate the transplantation techniques in the rabbit. METHODS: Left unilateral lung allotransplantations were performed in 10 pairs of Japanese white male rabbits, weighing from 2.8 to 3.7 kg. Rabbits were divided into two groups. Group A rabbits (n=5) received Cyclosporine A (CsA) (20 mg/kg/day) orally for 5 days postoperatively, while Group B rabbits (n=5) received no CsA. All rabbits were sacrificed at the fifth postoperative day for histological examinations. RESULTS: Anastomoses of the pulmonary vein were achieved by using the atrial cuff technique. Satisfied blood flow was obtained in all arterial and venous anastomosis sites. Bronchial anastomosis was also well healed and all rabbits could maintain adequate spontaneous ventilation. In Group A, histopathology revealed that three cases were grade A0, one was grade A1 and the other was A2. In Group B, three cases lived for five days, and histopathology showed two cases were grade A2 and one case was grade A3. CONCLUSION: We established a left unilateral lung allotransplantation model in the rabbit and observed suppression of acute rejection of the transplanted lung by CsA. This study suggests that the rabbit is also an experimental model suited for the analysis of lung preservation as well as lung allotransplant rejection.  相似文献   
14.
Malignant peripheral nerve sheath tumors (MPNSTs; malignant schwannomas) rarely occur in the anterior mediastinum, and their prognosis is poor. A 75-year-old man was referred to our hospital for examination of an anterior mediastinal tumor. A computed tomography-guided percutaneous needle biopsy revealed only fibrosis. The tumor was completely excised via a median sternotomy with partial resection of the pericardium and right upper lobe of the lung. Thereafter, the tumor was diagnosed as a storiform-pleomorphic type of malignant fibrous histiocytoma. At 1 year after the surgery, a distant metastasis was found in the interlobular space between the right middle and lower lobes. The tumor was completely excised via a right posterolateral thoracotomy. Reexamination of the primary and secondary tumors revealed an MPNST. No recurrence was found up to 5 years after the second surgery without adjuvant chemotherapy or radiation therapy. However, he died from multiple lung metastases after 6 years.  相似文献   
15.
Efficacy of Intraoperative Cooling Methods   总被引:3,自引:0,他引:3  
Background: Patients may require perioperative cooling for a variety of reasons including treatment of a malignant hyperthermia crisis and induction of therapeutic hypothermia for neurosurgery. The authors compared heat transfer and core cooling rates with five cooling methods.

Methods: Six healthy volunteers were anesthetized with desflurane and nitrous oxide. The cooling methods were 1) circulating water (5 [degree sign] Celsius, full-length mattress and cover), 2) forced air (10 [degree sign] Celsius, full-length cover), 3) gastric lavage (500 ml iced water every 10 min), 4) bladder lavage (300 ml iced Ringer's solution every 10 min), and 5) ice-water immersion. Each method was applied for 40 min or until the volunteers' core temperatures approached 34 [degree sign] Celsius. The volunteers were rewarmed to normothermia between treatments. Core cooling rates were evaluated using linear regression.

Results: The first volunteer developed abdominal cramping and diarrhea after gastric lavage. Consequently, the technique was not again attempted. Bladder lavage increased heat loss 10 [nearly =] 10 W and decreased core temperature 0.8 +/- 0.3 [degree sign] Celsius/h (r2 = 0.99 +/- 0.002; means +/- SD). Forced-air and circulating-water cooling comparably increased heat flux, [nearly =] 170 W. Consequently, core cooling rates were similar during the two treatments at 1.7 +/- 0.5 [degree sign] Celsius/h (r2 = 0.99 +/- 0.001) and 1.6 +/- 1.1 [degree sign] Celsius/h (r2 = 0.98 +/- 0.02), respectively. Immersion in an ice water slurry increased heat loss [nearly =] 600-800 W and decreased core temperature 9.7 +/- 4.4 [degree sign] Celsius/h (r sup 2 = 0.98 +/- 0.01). Immersion cooling was associated with an afterdrop of [nearly =] 2 [degree sign] Celsius.  相似文献   

16.
Abstract: To prevent side effects from a silicone shim in Isshiki thyroplasty type I, we used a ceramic shim in 10 patients with unilateral recurrent laryngeal nerve paralysis. No published reports have described the use of ceramic in this type of surgery. According to the degree of glottic insufficiency, ceramic shims of various heights were inserted into the fenestration made in the thyroid ala. All patients experienced subjective improvement of voice postoperatively. Laryngoscopies in most cases showed that glottic insufficiency improved postoperatively. In the postoperative examination, the maximum phonation time improved an average of 3.7 s, and the mean flow rate improved an average of 331 ml/s. We have analyzed the relationship of these improvements to the degree of glottic insufficiency and have compared our results with those of other investigators.  相似文献   
17.
Summary The dynamics of paraquat in the stomach and esophagus of rats were demonstrated using immunohistochemical techniques. The Rats were killed 3 h, 12 h, 24 h, 3 days, 7 days and 10 days after intravenous administration of paraquat. In the stomach, paraquat was localized in the epithelial cells between 24h and 10 days after injection, whereas in the esophagus, paraquat was localized in epithelial cells and the lamina propria mucosa between 12 h and 10 days after administration. Although these findings were similar to those observed in the intestine of rats, no clear changes in the distribution of paraquat with time were observed; suggesting that the stomach and esophagus are important reservoirs for the redistribution of paraquat.  相似文献   
18.
Eighteen patients with serious pleuritis carcinomatosa with remarkable pleural effusion were treated with a new pleurodesic therapy, and all the patients treated obtained favorable results. After removing pleural effusion, fibrinogen solution was intrapleurally instilled and then, our newly devised material, G.T.XIII and an anticancer drug, Adriamycin (ADM), were administered as chemosclerosing agents in an attempt to prevent recurrence of the effusion and also to provide locoregional antineoplastic effects. Recurrence of pleural effusion was nil in all patients treated, and subjective complaints of the patients were remarkably relieved. There were 14 patients evaluable, and all the response of these patients resulted in partial response (PR) according to the World Health Organization (WHO) criteria. Improvement of performance status (PS) was observed in 61% (11/18). Eight patients could be discharged. Three patients have remained alive. Fifteen patients died after the therapy, and their median survival was 67 days. Eight patients were autopsied. The postmortem examinations confirmed that fibrous adhesion in the pleural cavity with these materials was significant, and evidence of recurrence of pleural fluid was not seen. Topical oncolytic effects of the ADM were histologically remarkable. This pleurodesis was called "Bio-adhesio-chemo (BAC) therapy."  相似文献   
19.
To determine the levels of maturation and differentiation ofmurine CD4 single-positive (SP) T cells, we compared the secondaryresponses of staphylococcal enterotoxin A (SEA)-induced neonatalthymic, adult thymic and adult splenic CD4 SP T cell blastsprepared from whole or heat-stable antigenlow CD4 SP T cells.Proliferative responses upon re-stimulation with SEA were strongin adult splenic CD4 SP T cell blasts, but quite weak in neonatalthymic and adult thymic CD4 SP T cell blasts. SEA-induced IL-2production was weaker in neonatal thymic blasts than in theadult splenic CD4 SP T cell blasts. In contrast, SEA-inducedIL-4 production was high in neonatal thymic CD4 SP T cell blasts,and low in adult splenic and thymic CD4 SP T cell blasts. Expressionof GATA-3, that directs production of IL-4 in T cells, examinedat protein and mRNA levels, was higher in neonatal thymic cellsthan in adult thymic and splenic cells. These results suggestthat neonatal and adult thymic CD4 SP T cells in the final stageof maturation are relatively immature compared with adult splenicCD4 SP T cells. The cytokine production profile of neonatalthymic CD4 SP T cells suggests that they are inclined towardsa Th2 response.  相似文献   
20.
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