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1.
neurogenetics - Mediator (MED) is a key regulator of protein-coding gene expression, and mutations in MED subunits are associated with a broad spectrum of diseases. Because mutations in MED17...  相似文献   
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Immunosuppressive activities of the newly discovered FK506, isolated from Streptomyces tsukubaensis, were examined by using cardiac allotransplantation in the rat, and the mechanisms underlying induction and maintenance of FK506-induced long-term allograft survival were studied. Male rats of WKA (RT1k) and F344 (RT1lvl) strains were used as recipients and donors, respectively, and those of BN (RT1n) strain were used as third-party donors. Treatment with FK506, beginning from the day of allografting for 14, 10, or as few as 4 days, prolonged allograft survival significantly across the major histocompatibility barrier. The minimum doses for prolonging graft survival were 0.1 mg/kg/day by intramuscular treatment and 1.0 mg/kg/day by oral treatment. Treatment with FK506 at a dose of 0.32 mg/kg/day from day 4 until day 10 resulted in all the grafts surviving indefinitely and from days 5 to 10, half the grafts survived indefinitely, suggesting that the agent inhibited ongoing rejection. On the other hand, cyclosporine treatment at a dose of 20 mg/kg/day from day 2 did not prolong graft survival time statistically significantly. Induction of prolonged graft survival was not obtained by pretreatment of the prospective donor or recipient; prolonging effects were observed only when the agent was administered after allografting. Thus, the primary effect of the agent is exerted on responder lymphocytes reacting to the donor antigens in the induction phase of long-term graft acceptance. The mechanisms underlying the maintenance of long-term grafts were analyzed by testing the capacity of lymphocytes or serum of long-term graft-bearing rats to inhibit graft rejection in irradiated grafted hosts. Transfer of 2 x 10(8) lymphocytes from FK506-induced long-term F344 graft-bearing WKA rats resulted in indefinite survival of F344 heart allografts, but it did not prolong survival of third-party BN hearts. Transfer of 2.5 ml serum from long-term graft-bearing rats also prolonged graft survival of F344 hearts, but not BN hearts. These results suggest that donor strain-specific suppressor cells and humoral factor(s) are induced by treatment with FK506 in the presence of allografts, and that they play at least partial roles in the maintenance of long-term allograft acceptance.  相似文献   
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Recently an essential role of interstitial cells of Cajal (ICC) within myenteric plexus (ICC-MY) was suggested in ascending contraction and descending relaxation in the mouse ileum. The role of ICC in these neural reflexes was examined in the distal colonic segments prepared from the wild type and c-kit mutant, W/W(V) mice, in the present study. Localized distension of the segments from the wild type mice by using a small balloon resulted in ascending contraction and descending relaxation. In the segments from the mutant mice, localized distension also induced these neural reflexes similar to those observed in the wild type mice. Immunohistochemical examination demonstrated that ICC-MY and ICC present in muscle layers (ICC-IM) were severely disrupted in the mutant mouse, but only ICC, present within submucosal plexus (ICC-SMP), remained unchanged. In the small strips with ICC-SMP absent prepared from the mutant mouse, electrical field stimulation induced contraction or relaxation in the absence or presence of atropine, respectively. It was suggested that ICC have no important role in the ascending and descending neural reflexes in the mouse distal colon, this is in direct contrast to the role of ICC-MY in the ileum.  相似文献   
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Minimum incision endoscopic nephrectomy for giant hydronephrosis   总被引:1,自引:0,他引:1  
Five consecutive patients with symptomatic giant hydronephrosis underwent minimum incision endoscopic nephrectomy. The originally huge renal specimen was retroperitoneally mobilized using both of endoscopy and direct vision, without the use of trocar ports or gas insufflation, via a single minimum incision that narrowly permitted extraction of the specimen. The specimen was successfully extracted from the incision in all patients. Technically, proper deflation of the hydronephrotic sac facilitates mobilization and enables extraction of the specimen. Median (range) size of incision, operative time, and estimated blood loss were 4 cm (3-5), 205 min (156-222), and 210 mL (110-350), respectively. No patient required blood transfusion or encountered operative complications. Postoperative convalescence was short and uneventful; all patients resumed oral intake and ambulance on the day following surgery, and were physically dischargeable from hospital after 2-3 postoperative days. Thus, this technique is a feasible, minimally invasive and safe procedure for symptomatic giant hydronephrosis.  相似文献   
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Renal cell carcinoma (RCC) causes many kinds of symptoms such as hypercalcemia, hypertension, polycythemia and fever. Here we describe a rare case of RCC presenting with a persistent cough. After radical nephrectomy, the obstinate cough disappeared. When the tumor recurred locally, the cough also recurred. Furthermore, the cough disappeared completely again after the removal of the recurrent tumor. Although all the clinical findings suggested that the RCC caused the cough, we could not identify a specific humoral substance responsible for the cough.  相似文献   
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Since 1998, we have performed minimum incision endoscopic surgery (MIES) for renal cell carcinoma (RCC). For seven dialysis patients with bilateral RCC, we have performed sequential bilateral MIES radical nephrectomy. It was carried out by retroperitoneal approach through a single minimum incision that narrowly permitted extraction of the specimen using endoscopy and direct stereovision, without trocar ports, without gas insufflation and without the insertion of the hands of operators into the operative field. Although six of the seven patients had multiple complications in addition to chronic renal failure (CRF), bilateral kidneys were successfully removed by sequential MIES radical nephrectomy without major operative complication. Postoperative recovery was prompt with all patients resuming oral feeding and walking by the second postoperative day. Sequential bilateral MIES radical nephrectomy, leaving the peritoneal cavity intact and without imposing circulatory stress caused by gas insufflation, is a feasible treatment for bilateral RCCs in dialysis patients.  相似文献   
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A case of an odontogenic tumor which invaded the intracranial space from the mandible is reported. Judging from the radiographic images it was similar to a malignant tumor. The patient died 17 years after the first visit. According to the final pathological diagnosis, it was malignant odontogenic mixed tumor of low grade which did not belong to any of the WHO classification.  相似文献   
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