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31.
In this study, the effect of combining anti-CD4 monoclonal antibody (mAb) and cyclosporin (CyA) therapy at the time of transplantation was examined. A mouse cardiac allograft model was used. Anti-CD4 mAb administered perioperatively induces long-term survival. The addition of a short course of CyA given subcutaneously in a regimen of either a high-dose treatment or a standard dose treatment to the anti-CD4 mAb treatment protocol did not have a detrimental effect on graft survival. Despite having no significant effect on graft survival, the addition of CyA to the treatment protocol did result in a significant decrease in the level of IL-2 present in the hearts 7 days after transplantation. The decrease in IL-2 production was directly related to the presence of CyA in vivo. When CyA treatment was continued throughout the period during which unresponsiveness to the graft is induced by anti-CD4 mAb therapy, 50 % of the grafted hearts were rejected once the CyA was discontinued. In conclusion, the combined use of anti-CD4 mAb therapy and CyA did not have a negative effect on graft survival in this model when the two agents were used concurrently at the time of transplantation. Received: 2 October 1996 Received after revision: 31 January 1997 Accepted: 5 February 1997  相似文献   
32.
A 45-year-old man was referred to our department in March of 1989. Physical examination showed erythroderma, palmo-plantar hyperkeratosis, generalized lymphadenopathy, hepatosplenomegaly, and leukemic manifestation. The lymphocyte count in the peripheral blood before treatment was 1.7 × 104 cells/mm3. Atypical lymphocytes such as flower cells and lobulated cells were seen in the peripheral blood. A sample excised from a lymph node showed immunoblastic, pleomorphic T cells by a modified classification scheme of the Working Formulation. A high level of serum LDH was detected (2.1 times the upper normal limit). Anti HTLV-1 antibody was also detected in the serum. The atypical lymphocytes were positive for CD3, CD4, CD5, CD7 and HLA-DR, and negative for CD8. Thus, the clinical, pathologic and immunologic features were those of typical acute-type ATL. The patient was treated with VEPA-M for three months starting in March of 1989. Because of poor response, the patient was then treated with MACOP-B, M-FEPA, and VEPP-B for about one year from June of 1989 and has been free of disease up to the time of writing, March of 1993.  相似文献   
33.
1. We previously reported that angiotensin II release from the mesenteric arteries of Wistar-Kyoto (WKY) and spontaneously hypertensive rats (SHR) increased in a time-dependent manner as a result of the isolation of the arteries and perfusion. This phenomenon appeared to be due to the withdrawal of circulating angiotensin II (AII). 2. The purpose of the present study was to test the hypothesis that vascular AII generation may be negatively regulated by circulating AII in WKY and SHR, and to clarify the role of this vascular angiotensin II in the sustained hypertension of SHR following nephrectomy. 3. The mesenteric arteries from kidney-intact and nephrectomized WKY and SHR were perfused and the amount of AII released into the perfusate was measured. The effects of the angiotensin converting enzyme inhibitor, captopril, and the effects of supplementation of renal renin and circulating angiotensins to nephrectomized rats, by blood exchange between kidney-intact and nephrectomized rats, on AII release were examined to clarify the pathway of vascular AII generation after nephrectomy. 4. Nephrectomy caused augmentation of vascular AII release both in WKY and SHR in spite of the abolishment of circulating renin. Captopril reduced this enhanced release of AII, but blood exchange did not affect it. There was no significant difference in these responses between WKY and SHR. 5. These results suggest that WKY and SHR have in common a potent pathway for production of vascular AII in response to the withdrawal of circulating AII, although this pathway is not responsible for the sustained hypertension of SHR after nephrectomy. The precise pathophysiological role of this pathway remains to be elucidated.  相似文献   
34.
Spontaneous photon emission (chemiluminescence, CL) as a monitor of free radical evolution in Drosophila melanogaster which had been maintained at 25 or 30 degrees C for 5 days after emergence was measured. When maintained at 30 degrees C the fly CL intensity was stronger than at 25 degrees C. Under the condition of the higher temperature, the fly life span was shorter (mean life span = 29 days at 30 degrees C and 63 days at 25 degrees C), and oxygen consumption (3.7 microliters/mg.h at 25 degrees C, 4.9 microliters/mg.h at 30 degrees C) and the mobility (movement distance = 25 mm/min at 25 degrees C, 700 mm/min at 30 degrees C) increased, together with augmentation of phospholipid hydroperoxide in the fly total lipids. The CL spontaneously emitted from fly homogenate was decreased by the free radical scavengers both in experiments in vivo and in vitro. The hypothesis is proposed that as the oxygen metabolism grows active, the chemiluminescent reactions that involve oxygen-dependent free radical metabolism, including membrane phospholipid hydroperoxidation, contribute to the acceleration of senescence of fly bodies.  相似文献   
35.
A head fixation system using four carbon fiber head pins and modified pin supporting devices is described. The fixation system was developed for intraoperative computed tomographic scanning and provides artifact-free images during open-field neurosurgery.  相似文献   
36.
37.
We have developed an implant heating system (IHS) for interstitial hyperthermia of brain tumors. IHS consists of three compartments: ferromagnetic implant with low Curie point, induction coil and generator to produce high frequency magnetic field. The device works as follows: It is heated up to a Curie temperature (Tc) by Eddy current under the magnetic field. Heat generated in the implant is conducted to the tumor tissue into which it has been implanted. To evaluate the effect of this hyperthermia, a brain tumor model was produced by innoculation of VX2 tumor cells and treated either by hyperthermia with IHS alone, chemotherapy with ACNU alone, or with a combination of both. The longest survival was obtained by the combined treatment, and significant prolongation of survival was found in the single treatment groups. In the Phase I clinical trial, one or several implants (1.8 mm X 15 mm, Tc = 68 degrees C) made of Fe-Pt alloy were placed in the tumor by CT guided stereotactic procedure, or manually during craniotomy. Hyperthermia of above 42 degrees C for 30 to 60 minutes twice a week was brought about in ten cases of malignant brain tumor. CT evaluation was made in nine cases treated for more than ten times in this way. Five out of the nine cases responded to this hyperthermia with irradiation. In conclusion, a safe, repeated and longterm treatment was possible without significant side effects. The hyperthermia with IHS may also be applicable to benign intracranial tumors and neoplasms in other part of body as well.  相似文献   
38.
39.
A 14-year-old junior high school boy was admitted to our institute. Previously he had been diagnosed as having peripheral pulmonary stenosis (Gay's classification, type IV) at the age of 2 years and 10 months. On this occasion, however, a diagnosis of supravalvular aortic stenosis was made, with a pressure gradient of about 120 mmHg, and all examinations showed spontaneous remission of peripheral pulmonary stenosis. He underwent a successful standard aortoplasty. This is the first reported case of spontaneous remission of peripheral pulmonary stenosis.  相似文献   
40.
The absorption and excretion and clinical effectiveness of cefixime (CFIX) granules, a new oral cephalosporin, were studied with pediatric patients with tonsillitis and urinary tract infection (UTI). Peak serum concentrations in 3 children given orally a single dose of 3 mg/kg on fasting were 0.545 micrograms/ml at 2 hours in 1 patient, and 1.56 and 1.26 micrograms/ml at 4 hours in the other 2. The half-lives in the 3 patients were 3.21-3.42 hours, with an average of 3.29 hours. The urinary concentration during the first 6 hours was 36.5 micrograms/ml in 1 patient showing the low serum level, and the first 6-hour urinary recovery rate was 7.3%. In the other 2 patients, urinary concentrations and recovery rates up to 6 hours were 87 and 62 micrograms/ml, and 17.0 and 15.1%, respectively. The second 6-hour urinary concentrations and recovery rates were 35.5 and 20.8 micrograms/ml, and 12.7 and 8.8%, respectively. The urinary recovery rates up to 12 hours were 29.7 and 23.9%, respectively. CFIX was given orally to 19 children with 20 diseases in daily doses of 6.4-12.9 mg/kg in 2 or 3 divided portions for 3 to 12 days. Clinical evaluations were made on 18 diseases. Clinical effects of CFIX were excellent in 4, good in 7 and poor in 1 of the 12 patients with tonsillitis, and excellent in 5 and good in 1 of the 6 patients with UTI. The overall clinical effectiveness rate was 94.4%. No side effects were observed in any of the 19 patients. Hematological tests, showed slight elevation of blood platelet counts in 2 patients.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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