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In a variety of human malignancies, alteration of the p53 tumour suppressor gene is known as a significant indicator of late progression events including invasion and metastasis, with a possible close relationship to genetic instability. Mutational analysis of the p53 and H-ras genes was performed for 10 pairs of N-butyl-N-(4- hydroxybutyl)nitrosamine-induced invasive mouse urinary bladder carcinomas and metastatic foci. p53 Mutations were found in nine of 10 (90%) primary carcinomas and seven of 10 (70%) metastatic foci. A total of eight p53 mutations in primary carcinomas were common in metastatic foci in six pairs. Additional p53 or H-ras mutations which were not identified in the primary carcinomas were found in three metastatic foci. Evaluation of the allelic distribution of the p53 mutations using RT-PCR, PCR and subcloning, further indicated possible intra-tumour genomic heterogeneity or excess copy numbers of the p53 gene due to genetic instability. Overall, p53 alterations were frequent in mouse urinary bladder carcinomas demonstrating progression. The results suggest that genetic instability might underlie generation of additional genetic alterations in this animal model.   相似文献   
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The purpose of this study was to apply an electronic nose system for evaluation of unpleasant odor in tablets containing L-cysteine, an unpleasant odor drug, and demonstrate the odor masking ability of thin-layer sugarless coated tablets, which we have newly developed, by both electronic nose system and sensory evaluations. We demonstrated the qualitative evaluation of the unpleasant odor using air as a reference indicator and the quantitative evaluation of the unpleasant odor using the distances between air and samples in the electronic nose system evaluation. The electronic nose system evaluation was positively and well-correlated with the sensory evaluation by volunteers. We suggest that the electronic nose system evaluation is appropriate as an alternative or a support method for sensory evaluation by volunteers. As the results of both electronic nose system and sensory evaluations, we demonstrated that the thin-layer sugarless coated tablets have excellent masking ability of the unpleasant odor, equivalent to that of sugar-coated tablets due to the dense coating layers.  相似文献   
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The association between congenital duodenal obstruction and concomitant choledochal cyst has not been reported, although duodenal obstruction is known to be associated with many other anomalies. The authors describe 2 patients with choledochal cyst with duodenal obstruction. In 1 patient, a diverticulum type of choledochal cyst was found within an annular pancreas. Cyst excision, choledochojejunostomy, and side-to-side duodeno-duodenostomy were performed. The other patient showed separated duodenal atresia and other multiple anomalies including imperforate anus. A choledochal cyst was noted at the time of duodeno-duodenostomy and sigmoid colostomy. Cyst-enterostomy was performed at the age of 8 months, but the patient died of multiple anomalies. Intraoperative cholangiography indicated an anomalous pancreatobiliary ductal junction (APBDJ). In both patients the bile in the cyst contained high levels of amylase, suggesting the presence of an APBDJ. An APBDJ is considered to play an etiologic role in the development of the choledochal cysts associated with duodenal obstruction.  相似文献   
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The issue of proper use of postmortem computed tomography (PMCT) in forensic fields is currently being actively discussed. The PMCT image has specific findings that differ from the antemortem image, and it is essential to understand and interpret postmortem changes in order to utilize PMCT properly. In this article, we present two cases of acute subdural hematoma (ASDH) in which images were obtained both ante- and postmortem. These images showed marked reduction of hematoma and diminishing midline shift between the agonal and postmortem periods, without evacuation of the hematoma. Attention should be paid to this phenomenon because key findings in determining cause of death could disappear if investigating the cause of death takes too long in cases that prove to be ASDH. In other words, this phenomenon potentially becomes a risk for misdiagnosis when we decide the cause of death without knowing the details of the circumstances of death.  相似文献   
77.
Lichen aureus is a rare, chronic, persistent purpuric dermatosis clinically characterized by striking yellow‐ to bronze‐colored lesions. Histologically, lichen aureus differs from other pigmented purpuric dermatoses in containing dense, band‐like infiltrates closely associated with the epidermis. This report describes 2 patients with lichen aureus, a 20‐year‐old woman with a lesion on her right arm and a 51‐year‐old man with a lesion on the right side of his groin. Skin biopsy specimens revealed almost identical findings in both patients, including dense band‐like infiltrates containing lymphocytes, histiocytes with hemosiderin deposits scattered extravasated red blood cells and nerve alterations at the dermo‐epidermal interface. The nerves within the lesions were filled with granules, which stained positive with antibody to microtubule‐associated protein 1A/1B‐light chain 3, suggesting autophagy within the nerves. These altered nerves were present only in areas of band‐like dermal lymphocytic infiltration. Electron microscopy of the lesions showed the accumulation of autophagosomes in Schwann cells.  相似文献   
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The Physiological and Operative Severity Score for the Enumeration of Mortality and Morbidity (POSSUM) is widely used to predict surgical complications affecting various organs. However, there are few reports about objective evaluation methods for head and neck surgery. In this study, we retrospectively examined the association between POSSUM score and actual surgical complications of head and neck reconstruction surgery. In total, 711 patients who underwent head and neck reconstruction after cancer extirpation between January 2007 and January 2015 were studied. The predicted risk of complications was calculated using the POSSUM score and compared with the actual rate of perioperative complications. Perioperative complications occurred in 178 (25%) patients, comprising systemic complications in 52 (7%) patients, surgical site infection of the head and neck area in 78 (11%) patients and failure of the free flap in 55 (8.8%) patients. When patients were divided into a perioperative complication group and a no-complication group, a significant difference between the two groups was observed in the predicted postoperative rate calculated from the POSSUM score (p?相似文献   
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