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141.
Hepatocyte transplantation is a potential therapeutic modality for overcoming the shortage of liver donors, and the clinical application of allogeneic hepatocyte transplantation has been considered. However, there are two major problems with allogeneic hepatocyte transplantation: protection of transplanted hepatocytes from rejection and stimulation of the rapid proliferation of surviving cells. Without immunosuppression, allogeneic hepatocytes are rapidly rejected within a few days after transplantation, even though it is relatively easy to induce immunotolerance after allogeneic whole liver transplantation. Accordingly, different rejection mechanisms seem to operate after allogeneic hepatocyte transplantation and whole liver transplantation. To overcome the rejection of transplanted hepatocytes, induction of donor-specific unresponsiveness to graft without compromising the host immune system would be ideal. We previously reported that the Fas-Fas ligand system plays a critical role in the CD28-independent pathway of hepatocyte rejection. Therefore, blockade of rejection using CTLA4 immunoglobulin (CTLA4Ig) or anti-CD80/86 monoclonal antibodies and anti-FasL monoclonal antibody may prolong the survival of transplanted allogeneic hepatocytes. Furthermore, administration of hepatocyte growth factor (HGF) can promote the proliferation of allogeneic hepatocytes and this may lead to the development of a functioning liver substitute.  相似文献   
142.
Summary. Chromosomal translocations involving band 3q27 are recently described common specific cytogenetic abnormalities in B-cell neoplasms, and the BCL-6 gene, identified on 3q27, was shown to be disrupted and over-expressed in lymphoma cells having these chromosomal translocations. In the present study we found rearrangements within the BCL-6 gene in seven out of 3 5 cases with B-cell non-Hodgkin's lymphoma (NHL). Further analysis revealed that three of these patients with BCL-6 abnormality had multiple rearranged bands hybridized with probes from a single restriction fragment within the major translocation cluster (MTC). suggesting that independent DNA rearrangements would occur on both alleles. Additionally, Southern blot analysis indicated that three patients carry deletions encompassing the area containing the first exon of the BCL-6 gene. Our results suggest that biallelic DNA rearrangements and deletions would occasionally occur in NHL patients with BCL-6 abnormality.  相似文献   
143.
Abstract Using a sleep log for 28 days in the summer vacation, 89 autistic children living in a suburb of Tokyo were examined. Only one girl of 13 years showed a tendency of non-24 h Sleep-wake syndrome. Most autistic children showed a large variation of total sleep time. Forty per cent of subjects showed 10% or more on coefficient of variation of total sleep time. In the retiring and rising time, many subjects tended to show late retiring and early rising.  相似文献   
144.
Abstract— In the present study, we examined the mode of action of KRN2391 (N-cyano-N′-(2-nitroxyethyl)-3-pyridinecarboximida-mide monomethanesulphonate) in isolated canine renal artery compared with those of nicorandil and cromakalim. KRN2391 (10?8-3 × 10?5 m ), nicorandil (10?7-3 × 10?4 m ) and cromakalim (10?8-3 × 10?5 m ) relaxed renal arteries contracted by 25 Mm KCl in a concentration-dependent manner. KRN2391-induced relaxation was inhibited by methylene blue (10?5 m ) and glibenclamide (10?6 m ). Nicorandil-induced relaxation was inhibited by methylene blue, but not by glibenclamide. The concentration-relaxation curve for cromakalim displayed a rightward parallel shift in the presence of glibenclamide. In the control observation, KRN2391 and nicorandil also produced full relaxation, but cromakalim did not. The present results suggest that KRN2391 acts as both a nitrate and a potassium channel opener, and nicorandil acts only as a nitrate and only in canine renal artery.  相似文献   
145.
Primary soft tissue sarcoma of the adrenal gland is very rare and aggressive. In right adrenal tumors, because of direct venous drainage into inferior vena cava, the tumor may invade the vena caval wall toward the right atrium. We present a case of adrenal leiomyosarcoma extending into the right atrium.  相似文献   
146.
Abstract— The present study was performed to determine whether KRN2391 (N-cyano-N′-(2-nitroxyethyl)-3-pyridinecarboximidamide monomethanesulphonate), a novel vasodilator, shows different effects on porcine isolated coronary arteries of different sizes. The vasodilating effects of KRN2391 on porcine large (2·5–3·0 mm outer diam.) and small (0·8–1·0 mm) coronary arteries were also compared with those of cromakalim, nicorandil, nifedipine, nitroglycerin and adenosine. The relaxant effects of these drugs were examined in coronary arteries contracted by 25 Mm KCl. Nitroglycerin caused greater relaxation in large vessels than in small vessels. In contrast, adenosine, nifedipine and cromakalim caused greater relaxation in small vessels. However, there was no difference between large and small vessels in the relaxing effects of KRN2391 and nicorandil. These unique features of KRN2391 and nicorandil appear to be beneficial in ischaemic heart disease.  相似文献   
147.
Recovery from viral myocarditis is usually excellent and completealthough it occasionally results in sudden death during itsacute stage. While neurohormonal mechanisms play an importantrole in the adaptation to heart diseases, little is known aboutthe alteration of the neurohormonal system in viral myocarditis.Therefore, we examined the myocardial ß-adrenergicreceptor and cardiac angiotensin I and II concentrations ina murine model of viral myocarditis induced by an encephalomyocarditisvirus. The down-regulation of the ß1-adrenergic receptorsubtype was observed on day 10. The heart weight, heart weight/bodyweight ratio and myocardial necrosis were significantly increasedat this stage. On day 30, the ß2-adrenergic receptorsubtype was up-regulated without up-regulation of the totalß-adrenergic receptor. Both angiotensin I and II concentrationswere significantly increased with myocardial hypertrophy inthe left ventricle on day 30. The up-regulation of the totalß-adrenergic receptor and ß2-subtype wasobserved on day 120, but neither the angiotensin I nor II concentrationwas increased. Therefore, the up-regulation of the ß2-adrenergicreceptor density and the temporal increase of the angiotensinI and II concentrations in the murine ventricle during viralmyocarditis may play an important role in the pathophysiologyof post-viral myocarditis.  相似文献   
148.
149.
A case of sclerosing cholangitis is presented. The patient was a 65 year-old male and visited a hospital because symptoms of a biliary tract infection suddenly appeared. These symptoms improved in the short term with antibiotic therapy. As a high level of serum CA19–9 was found and the double wall structure of the intrahepatic bile duct and a portal thrombus were observed during an abdominal ultrasonography, the patient was transferred to our clinic for further examination of his hepatobiliary system. A malignant lesion was suspected from an endoscopic retrograde cholangiography and celiac angiography, although the patient's serum CA19–9 level rapidly decreased after admission. A liver with a smooth surface, some focal wide depressions, and an increase of white markings was observed laparoscopically. An adenomyomatosis-like lesion was observed in the gallbladder. Bile duct destruction with periductar fibrosis was histologically proven. This is a case of histologically diagnosed sclerosing cholangitis but without the typical findings usually found during an endoscopic retrograde cholangiography.  相似文献   
150.
We report here two cases of submucosal ectopic gastric mucosa which grew with pedunculation. A lesion 23 mm in size was located in the posterior wall of the upper gastric body in a 61-year-old female. A 58-year-old female had a lesion 12 mm in size in the anterior wall of the upper gastric body. Both were elevated lesions expressed as Yamada's type IV and were endoscopically diagnosed as submucosal tumors. For the purpose of total biopsy, endoscopic polypectomy was performed in both cases. Histological examination of the polypectomized specimens showed gastric mucosa in the submucosal layer. These two cases were unique in that ectopic gastric mucosa was pedunculated and diagnosed after endoscopic polypectomy, not by postoperative pathological examination.  相似文献   
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