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71.
Sadao Ii Hiroyuki Tsuchiya Koutaro Takazawa Hiroshi Minato Katsuro Tomita 《Journal of orthopaedic science》2004,9(2):152-156
Adamantinoma is a rare low-grade malignant bone tumor with an indolent course. The tibia is involved in 85%–90% of long-bone cases. We encountered a patient with primary adamantinoma of the proximal femur. A 60-year-old woman fell and fractured her proximal left femur in the area of a cystic lesion. She underwent an osteosynthesis procedure, and bone union was obtained. After 3 years she developed pain in the left thigh, and a radiographic abnormality was found at the fracture site. A metastatic bone tumor was suspected, and curettage and cementing were carried out. Histologically, we found an epithelial component but failed to detect any primary cancer. Local recurrence became evident after another 6 years. A marginal excision was performed and a bipolar femoral prosthesis was implanted. We finally diagnosed the patient with adamantinoma. In this report we describe the characteristics of this tumor and discuss the reasoning concerning the differential diagnosis and therapeutic plan. 相似文献
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Abstract – Though the use of mouthguards (MGs) has increased with the increase in sporting activities, little is known about the influence of their fabrication methods on longitudinal dimensional stability. The objective of this study was to compare the difference in the longitudinal dimensional stability between single and laminated MGs. Single-layer MGs were made from a 4.0 mm thick ethylene vinyl acetate (EVA) sheet and laminated MGs were made from two 2.0 mm thick sheets of EVA. MGs were kept in a 37°C water bath for 60 h, equivalent to the time period of 3-months inter-oral use. MG deformation was analyzed by measuring designated points on the MG border using a profile projector (J-12, Nikon Inc., Tokyo, Japan) before and after the water immersion. A finite-element model was also created to examine the time course of stress accumulation during the sheet forming process using Finite Element software. Longitudinal deformation was smaller in the laminated MGs than in the single-layer MGs in the anterior area ( P < 0.05). Finite element method (FEM) analysis also showed the largest stress accumulation in the anterior incisal area where deformations were mainly observed. Laminated double layer MGs have advantages over single-layer MGs in terms of longitudinal stability due to lower stress accumulation during the fabrication process. 相似文献
75.
H Nakanishi T Monden H Morimoto T Kobayashi T Shimano T Mori 《British journal of cancer》1991,64(2):239-242
Perforin (PFP) is a cytotoxic protein released from killer cells. PFP immunoreactivity in human peripheral blood lymphocytes (PBL) and tumour infiltrating lymphocytes (TIL) was investigated immunocytochemically with the aid of an anti-PFP monoclonal antibody. PFP was detected in the cytoplasm of 10% of PBL. We performed a double staining of PFP+ cells with Leu11b/CD16, Leu2a/CD8, or Leu3a/CD4 and showed that PFP was produced by 9% of CD8+ cells and 18% of CD16+ cells but not by CD4+ cells. In 28 colorectal cancer tissues, PFP immunoreactivity was observed in the lymphocytes infiltrating to the tumour stroma. The PFP+ cells were most numerous in Dukes A and decreased in number according to the progression of tumours. The PFP+ cells in TIL exhibited the same phenotypes as those in PBL but the PFP+ cells were more numerous in CD8+ cells than in CD16+ cells at all stages. This study represents the first evidence that PFP is mainly secreted from CD8+ cells in tumour tissues. It is hypothesised that the decrease in the number of PFP+ cells in accordance with tumour progression may reflect the suppression of the hosts local immunity. 相似文献
76.
S Kobayashi 《Nihon Geka Gakkai zasshi》1987,88(6):715-726
Among the patients with liver cirrhosis (LC) who undergo the operation, the postoperative complications are not infrequent and sometimes prove fatal. The impaired hepatic function, especially the impaired reticuloendothelial system (RES) function, has been claimed to be a possible pathogenic factor for these complications. The present experimental and clinical studies were undertaken to investigate the RES function and the effect of preoperative OK-432 administration as an RES potentiator in LC. The results are as follows: 1) CCl4-induced LC rats were evaluated for RES global phagocytic function, Kupffer cell phagocytic function, plasma opsonic activity and plasma opsonic substances such as fibronectin, C3 and IgG. All parameters except IgG showed significant depression compared to those values in normal rats. However, the administration of OK-432 (0.1 KE/rat, ip) improved all these depressed parameters. The OK-432 administration also significantly improved the survival following panperitonitis in LC rats. 2) Among 18 LC patients with hepatocellular carcinoma undergoing partial hepatectomy, the RES global phagocytic function, plasma opsonic activity and plasma opsonic substances were evaluated. Same as the experimental study, all parameters except IgG were significantly depressed among the LC patients compared to those values in the patients with normal liver. However, the preoperative OK-432 administration (5 KE/day sc for 4 days) significantly improved these parameters and consequently decreased the postoperative complications. These results indicate that the preoperative RES activation by the OK-432 was effective and useful for the prevention of the postoperative complications in the LC patients. 相似文献
77.
78.
Shiro Oka Shinji Tanaka Iwao Kaneko Hiroyuki Kanao Kazuaki Chayama 《Digestive endoscopy》2007,19(Z1):S30-S33
Endoscopic submucosal dissection (ESD) for colorectal tumors is steadily being developed. Safety and standardization of ESD for colorectal tumors have not been yet established because of the technical difficulties and the unsuitable anatomical characteristics of the colon and rectum. The authors mainly use a Flex knife for mucosal incision and a Hook knife for submucosal dissection to perform ESD safely. Skillful colonoscopic control, selection of scope, distal attachment tip hood, adequate high‐frequency generator and correct approach strategy should all be considered for safe performance of ESD. However, the incidence of indicative lesions is rare because the majority of colorectal tumors are adenomatous large laterally spreading tumors, which can be cured by intentional endoscopic piecemeal resection. At present, ESD for colorectal tumors should be performed only at central facilities that have expert colonoscopists. With the development of new devices and associated techniques, technical standardization of ESD for colorectal tumors is expected in the near future. 相似文献
79.
Novel SCN5A mutation (Q55X) associated with age-dependent expression of Brugada syndrome presenting as neurally mediated syncope. 总被引:1,自引:0,他引:1
BACKGROUND: An association between Brugada syndrome and neurally mediated syncope has been described. Although mutations in SCN5A have been identified in Brugada syndrome, the genetic link between Brugada syndrome and neurally mediated syncope has not been determined. OBJECTIVES: The purpose of the study was to clinically and genetically characterize a man with recurrent syncope that originally was diagnosed as neurally mediated syncope at age 8 years but subsequently manifested as Brugada syndrome at age 17 years. METHODS: The proband underwent clinical examination, which included head-up tilt test, sodium channel provocation test, and electrophysiologic study. Genetic screening of SCN5A was performed for the proband and his family members. The biophysical properties of a mutant SCN5A channel in a heterologous expression system were studied using whole-cell, patch clamp technique. RESULTS: The proband showed positive head-up tilt test, coved-type ST elevation recorded from the third intercostal space, and positive pilsicainide provocation test. Ventricular fibrillation was inducible at programmed electrical stimulation, consistent with characteristics of both Brugada syndrome and neurally mediated syncope. A novel nonsense SCN5A mutation (Q55X) was identified in the proband, his mother, and his asymptomatic brother. The heterologously expressed mutant channel was nonfunctional. CONCLUSION: We genetically determined an SCN5A mutation in a patient showing the combined phenotype of neurally mediated syncope and Brugada syndrome. Neurally mediated syncope and Brugada syndrome may share, at least in part, a common pathophysiologic mechanism. 相似文献
80.
K. Kim T. Mizunari N. Mizutani S. Kobayashi K. Takizawa H. Kamiyama Y. Murai A. Teramoto 《Acta neurochirurgica》2006,148(3):353-357
Summary We describe a giant aneurysm of the anterior communicating artery (ACoA) which was treated with a STA-RA graft-A3 bonnet bypass
and A3–A3 side-to-side anastomosis. A giant and partially thrombosed ACoA aneurysm was partially coated 3 years before his
current presentation, its gradual increase producing visual field disturbances. An A3–A3 side-to-side anastomosis and STA-RA
graft-A3 bonnet bypass were performed. The aneurysm was dissected, and the thrombus removed under transient parent-artery
occlusion. The aneurysmal neck was successfully clipped without encountering ischemic changes. This strategy may be useful
for treating giant or thrombosed aneurysms in the region of the ACoA. 相似文献