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Activating mutations in the beta-catenin gene is thought to be responsible for the excessive beta-catenin signaling involved in the majority of colon carcinomas in rodent models. Our recent study which indicated that beta-catenin mutations are present frequently in early dysplastic lesions of rat colon induced by a colon-specific carcinogen, azoxymethane led us to perform more specifically a comparative study regarding types of the beta-catenin mutation as well as K-ras mutations between such early appearing lesions and colon tumors. Male F344 rats, 6 weeks old, received s.c. injections of azoxymethane (15 mg/kg body weight) once a week for 3 weeks, and were killed at 16 and 46 weeks of age. Colons of animals killed at 16 weeks of age were processed for early altered lesions. Colon tumors from animals killed at 46 weeks of age were evaluated histopathologically. Laser capture microdissection system was used to obtain DNA of epithelial cells in both intramucosal lesions and colon tumors. After amplification of exon 3 of the beta-catenin gene and exon 1 of the K-ras gene, the products were then sequenced directly in both directions. Mutations in the exon 3 of beta-catenin gene were detected in 22 of 56 early lesions (39.3%) and 21 of 37 colon cancers (56.8%). Remarkably, all beta-catenin mutations detected in the colon tumors converged at codons encoding functionally important residues that may directly mediate beta-catenin degradation, whereas mutations in the early appearing lesions were found to be scattered in the exon 3 of the gene. K-ras mutations were also detected in 24 of 56 early lesions (42.9%) and 11 of 37 colon cancers (29.7%). All K-ras mutations converged at codon 12 and codon 13, even in the early lesions. The results of this study provide evidence for the first time that beta-catenin mutation is selected during the colon carcinogenesis. Our results also suggest that the activation of beta-catenin signaling pathway is not only an initiating event, but also plays a pivotal role in the promotion stage of colorectal carcinogenesis.  相似文献   
43.
Although most patients who have cutaneous T-cell lymphoma have an indolent clinical course, patients who have cutaneous tumors, lymph node or visceral involvement, or peripheral blood involvement generally have rapidly progressive disease with shorter survival. In those patients with poor prognostic features, conventional combination chemotherapy is usually ineffective. High-dose chemotherapy with autologous hematopoietic stem cell transplant (HSCT) results in high remission rates, but the recurrence is inevitable and rapid. Allogeneic HSCT, in contrast, provides durable long-term remissions and is currently the only potentially curative therapy.  相似文献   
44.
In 1991, a carcinoid tumor of the duodenum with metastasis in the regional lymph nodes was resected in a 39-year-old-man. A metastasis in the mediastinum was found and was resected in 1996. In 1999, a metastasis in the left lung was discovered and was excised. In 2001, he noticed right-sided diplopia, and a computed tomography (CT) scan disclosed a tumor of 2 cm diameter in the right orbit with infiltration to the frontal sinus. The tumor was resected, and was diagnosed metastatic carcinoid tumor. An orbital metastasis of carcinoid tumor is rare, and only about 30 cases have been reported in the English literature. The rarity metastasis of carcinoid tumors in the orbit prompted us to report this case.  相似文献   
45.
Clitoral reduction, especially in an adult, is a rare procedure which often leaves the glans clitoris without the capacity for tactile sensation. We present the case of a 34-year-old woman with symptomatic clitoromegaly since puberty who underwent a clitoral reduction procedure designed to preserve the neurovascular supply of the glans clitoris. The surgical technique presented here removes the corpora cavernosa of the clitoris, but conserves important neurovascular attachments. While this procedure was done on an adult, it could just as easily be performed on children or adolescents with clitoromegaly, typically the at-risk group for this condition.  相似文献   
46.
The ischial region is a common site of pressure sore. The ischial pressure sore with a large subcutaneous bursa is resistant to conservative treatment and tends to require radical surgical treatment. In this article the authors describe their experience with a simple surgical treatment on 8 ischial pressure sores in 7 patients with subcutaneous bursa by means of sclerotherapy using absolute ethanol. This method involves causing the bursa to become scarred and closing it up by sterilizing, fixing, and denaturing by the pharmacologic effect of absolute ethanol instead of surgical excision of the bursa. This alternative method has a possibility of treating pressure sores as well as other fistulous diseases in various areas.  相似文献   
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The aim of the study was to evaluate the outcome of a community-based prevention program against suicides among the elderly aged 65 and over in the Japanese rural town of Joboji (population 7,010), using a quasi-experimental design with two neighboring control areas. During the 10-year implementation of the program based on strategies including screening for depression, follow up with mental health care or psychiatric treatment and health education on depression, the relative risks estimated by the age-adjusted odds ratios for both males and females were reduced to almost one quarter more than a regional historical trend, with a better response to education for females than for males. A community-based management for later-life depression with mental health care supported by the psychiatric treatment can be effective against suicide among the elderly for both males and females.  相似文献   
50.
A 52-year-old man was admitted with anemia and slight fever, which he had for the last 2 months. He had undergone replacement of the ascending aorta for acute aortic dissection 10 years previously. Echocardiography demonstrated a flailing thin structure in the anterior wall of the ascending aorta corresponding to the proximal portion of the prosthetic graft. This abnormal echocardiographic finding led us to repeat blood cultivation. We finally detected Enterococcus facium and Staphilococcus epidermidis in his blood sample. We diagnosed this as a graft infection and prepared for surgical re-replacement of the infected graft. While he was waiting for the operation, an infectious aneurysm of a tibialis posterior artery ruptured and an emergency operation was done. Replacement of the infected ascending aorta graft was done thereafter. In surgery, 2-cm-long vegetation was found. It stuck to the graft wall near the former hole used for air removal in the first surgery. The patient recovered fully and left our hospital after 3 months of postoperative antibiotics therapy. This rare case of aortic graft infection long after the original replacement surgery suggests the importance of thorough echocardiographic investigation of prosthetic graft infection as a possible cause of fever of unknown origin.  相似文献   
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