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31.
Over 100 mutations in the presenilin‐1 gene (PSEN1) have been shown to result in familial early onset Alzheimer disease (EOAD), but only a relatively few give rise to plaques with an appearance like cotton wool (CWP) and/or spastic paraparesis (SP). A family with EOAD, seizures and CWP was investigated by neuropathological study and DNA sequencing of the PSEN1 gene. Aβ was identified in leptomeningeal vessels and in cerebral plaques. A single point mutation, p.L420R (g.1508T > G) that gives rise to a missense mutation in the eighth transmembrane (TM8) domain of PS1 was identified in two affected members of the family. p.L420R (g.1508T > G) is the mutation responsible for EOAD, seizures and CWP without SP in this family.  相似文献   
32.
Objective: Impacts of mediastinal lymph node dissection on a patient’s course after pulmonary resection is unclear in octogenarians with non-small cell lung cancer. Methods: Retrospectively identified subjects included 39 octogenarians and 1 nonagenarian, with grades according to the Charlson Comorbidity Index ranging from only 0 to 2. We performed mediastinal lymph node dissection in 19 patients (D group), and just lymph node sampling biopsy in the other 21 (S group). We compared clinicopathologic features and outcome after surgery between both groups. Results: Deterioration of performance status at the time of discharge, evident in 17 patients overall, was significantly more frequent in the D group. Postoperative complications occurred in 27 patients overall and there was no significant difference between the two groups. Survival rates in younger patients at 1, 3, and 5 years were 86, 59, and 49%, respectively; in octogenarians these were 83, 58, and 42% (no significant difference). Nor did survival differ significantly by surgical management of mediastinal lymph nodes; 1-, 3-, and 5-year survival rates were 94, 63, and 40%, respectively in the D group and 78, 66, and 43%, respectively in the S group. Conclusion: Octogenarians with non-small cell lung cancer should be treated by urgent pulmonary resection whenever possible. Since mediastinal lymph node dissection has little effect on long-term survival or the carried risk of worsening performance status at discharge, pulmonary resection without complete mediastinal lymph node dissection should be considered.  相似文献   
33.
Living donor liver transplantation (LDLT) for patients with portal vein thrombosis (PVT) involves technical difficulty. The aim of this research was to analyze their preoperative diagnosis of PVT, operative procedures, and postoperative courses of patients with preoperative PVT. Thirty-nine patients of 404 adult patients (9.7%) undergoing LDLT in our hospital from 1996 June to 2004 December had PVT at their transplantation. Twenty-nine patients had intractable ascites, 21 had gastrointestinal bleeding, and 18 had encephalopathy. The thrombus was located in the portal trunk in 23, in the portal trunk and superior mesenteric vein (SMV) in 7, and developed into the SMV and the splenic vein in 8. The occlusive grade was partial in 29, and complete in 10 patients. The thrombus was removed by a simple technique, and eversion and/or incision technique, or total removal of the portal vein (PV). The PV was reconstructed with the thrombectomized native PV, with an interposed vein graft, or porto-caval hemitransposition. Advanced PVT had a significant impact on blood loss and hospital mortality. Three out of 10 patients with residual PVT required radiological and/or surgical intervention after transplantation. In conclusion, thorough planning is essential for a successful LDLT outcome for patients with preexisting PVT.  相似文献   
34.
Background: Olfactory neuroblastoma is a rare sino‐nasal tumor arising from the olfactory epithelium and is often characterized by local invasion or metastasis. The role of chemotherapy in the treatment of this tumor is unclear. The purpose of this study was to review our institution’s experience of chemotherapy for advanced or recurrent olfactory neuroblastoma. Methods: Twenty‐one patients with histologically proven olfactory neuroblastoma were treated at our institution between 1992 and 2002. Twelve of these patients received chemotherapy in the setting of unresectable or recurrent disease and were retrospectively reviewed for clinical characteristics, treatment outcome or survival. Results: Eight patients of the 12 patients received cisplatin‐based chemotherapy and the remaining four patients received chemotherapy consisting of docetaxel plus irinotecan (three patients) or cyclophosphamide, doxorubicin, and vincristine (1 patient). A partial response was achieved in five patients, with an overall response rate of 42%, although the chemotherapeutic regimens were heterogeneous. Two partial responses were obtained among the three patients who received docetaxel plus irinotecan. The response rate to chemotherapy was 83% in the younger age group (<40 years), as opposed to 0% in the older age group (≥40 years), and the difference between the two groups was statistically significant (P = 0.02). Conclusion: Our study indicated that olfactory neuroblastoma would be sensitive to chemotherapy, especially with young patients. Docetaxel plus irinotecan has the possibility of showing favorable response, and warrants further investigation.  相似文献   
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The effects of spironolactone (5% SYC-201G, a preparation developed for clinical use in acne vulgaris by Searle Yakuhin K.K.), which is known to have antiandrogenic effects by competitively inhibiting dihydrotestosterone at androgen receptor sites, was topically applied to the androgen stimulated sebaceous glands of adult female golden hamsters. Androgen stimulation, induced by intramuscular injection of testosterone propionate (TP) every other day over a two week period, resulted in a 2.5 to 2.7 time increase in the size of the sebaceous glands of the hamster pinna. Once-daily treatment with 5% SYC-201G or matching placebo was applied to androgen-stimulated hamsters on one pinna only during the same period as TP injection. Comparison between the treated and untreated sides revealed a significant suppression in the sebaceous gland size (p<0.05) by 5% SYC-201G; no such effect was observed with placebo. The difference in the suppression rate of the sebaceous gland size between 5% SYC-201G (23%) and matching placebo (–4.7%) was significant (p<0.01).  相似文献   
38.
A combination of Photo Radiation Therapy (PRT) using Argon-Dye Laser with hematoporphyrin derivatives (HpD) was used experimentally on a cytogenetically highly malignant neuroblastoma xenograft, which exhibited a homogeneously staining region and caused DNA amplifications in chromosomes. The tumor tissue was treated with 500 joules/cm2 of laser. The dosage of HpD was 50 mg per kg body weight. Necrosis of over 50% of the tumor was observed in half the specimens. Swollen cytoplasmic organelles and ruptured cell and nuclear membranes were observed by electron microscopy after PRT. PRT may be used with other treatment modalities for the removal of residual and metastatic tumors.  相似文献   
39.
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   
40.
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