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51.
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We examined cell loss (apoptosis) and proliferation in a histopathological spectrum of epidermal squamous cell neoplasia, including 11 cases of solar keratosis (SK), 18 Bowen's diseases (BD) and 19 invasive squamous cell carcinomas (SCC). Apoptotic and proliferative cells were determined by terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-digoxigenin nick end labeling (TUNEL) and by the detection of nuclear antigen Ki-67, respectively. Few apoptotic cells were observed in normal epidermis, while TUNEL index (TI; percentage of TUNEL-positive cells) was highest for SCCs, followed by BDs and SKs, in the order given. Although the mean Ki-67 index did not differ between SCCs and BDs. both disease types showed a significantly higher index than the SKs. Of SCCs, both TI and Ki-67 index values were significantly higher in poorly than in well differentiated carcinomas. TI was significantly higher in SCCs without P53 immunohistochemical expression than in SCCs with P53 expression, while TI and Ki-67 indices did not correlate with P53 expression in the SKs and BDs. These results suggest that apoptosis reflects not only cell loss, but also proliferative activity in the epidermal neoplastic lesions.  相似文献   
53.
Smartphones have become essential devices in modern society. The coverage rate of smartphones in 2017 in Japan was 75% according to the Ministry of Internal Affairs and Communications. The iPhone is one of the most well-known smartphone brands. According to the manufacturer of iPhones (Apple), more than 200 million iPhones had been sold worldwide by 2017. These devices are often charged at night-time, especially while being used in bed. There are only three reports of smartphone charger-induced skin damage. We present two new cases of skin ulcers induced by an iPhone charger. The iPhone’s “lightning cable” has electrodes outside, and we found that this can present a higher risk of causing a skin injury compared with other types of phone chargers. We also investigated the mechanism of the skin ulcers caused by the iPhone charger. The results indicated that these ulcers were chemical burns rather than an electrical injury or heat-induced burn.  相似文献   
54.
OBJECTIVE: Since the majority of the key elements such as trigeminal nerves, parasympathetic nerves, nasal glands, and blood vessels targeted by histamine and leukotrienes are found in the lamina propria of the nasal mucosa, its selective electrocautery has a rationale to improve the symptoms of allergic rhinitis with preservation of epithelial layer. To achieve the above goal, we performed the submucous electrocautery of the lamina propria (SECLP) following the submucous resection of the inferior turbinate bone (submucous turbinectomy: SMT). This paper discusses the efficacy of this procedure for the patients with persistent perennial allergic rhinitis. METHODS: An intranasal initial incision was made along the piriform aperture. The mucoperiosteum was elevated from the inferior turbinate bone followed by its complete resection. The SECLP was performed by applying a high-frequency coagulation current with a ball tip electrode, which was inserted into the mucoperiosteal sack after the completion of the SMT and was drawn forward on the medial surface of the mucoperiosteum with drawing a wavy line. We performed this surgery in 43 patients with perennial allergic rhinitis who were refractory to pharmacotherapy or were reluctant to take medicine. Symptoms, macroscopic intranasal findings, the results of allergic tests, nasal resistance, mucociliary function with saccharin, and the number of mast cells were compared pre- and postoperatively. RESULTS: The patients exhibited satisfactory improvement in symptoms only with a few crust formations. The macroscopic intranasal findings and allergic tests improved after surgery. Saccharin transport time remained normal. The number of anti-tryptase positive mast cells significantly decreased in the epithelial layer and in the superficial layer of the lamina propria of the postoperative inferior turbinate mucosa. CONCLUSION: The SECLP following the SMT is evaluated to be a useful surgical modality for allergic rhinitis with preservation of the nasal mucosal function.  相似文献   
55.
We report a 54-year-old Japanese woman who developed liver tumors 102 months after hepatic resection for hepatocellular carcinoma (HCC) and percutaneous transluminal angioplasty (PTA) for membranous obstruction of the inferior vena cava (MOVC), which is one form of Budd-Chiari syndrome. In the present admission workup showed no evidence of co-infection with hepatitis B and C viruses. Dynamic computed tomography (CT) and magnetic resonance imaging showed an enhanced lesion, 1.5cm in diameter, in segment 3 of the liver, and no obstruction of the inferior vena cava after PTA. CT during both arterial portography and hepatic arteriography revealed another lesion, showing different hemodynamics, in segment 2. The patient therefore underwent hepatic resection, and the tumors were diagnosed histologically as HCC. The two tumors differed in their morphological features, one containing abundant fibrous stroma, whereas the other did not. The nontumorous liver tissue showed central zonal fibrosis, i.e., reversed lobulation, and partial expansion of nodule-like formations, indicating lack of progression since the situation seen at the initial hepatectomy. The presence of nontumorous liver tissue showing the above features suggests that, even after successful treatment for relief of congestion, patients who have had MOVC should be followed closely for as long as possible because of the risk of HCC recurrence. This is the first reported case of HCC recurrence after successful treatment of MOVC.  相似文献   
56.
A rare case of systemic vasculitis with second component of complement (C2) deficiency was documented in a patient who developed colonic ulcerations, jejunal edema and dilatation, cutaneous ulcers, peripheral neuropathy, and psychosis. Colonoscopy revealed typical features of ischemic colitis and radiological examination showed ischemic changes in the jejunum and ileum. Histopathological examination of the cutaneous biopsy revealed typical necrotizing vasculitis. It is very likely that multiorgan involvement, including ischemic changes of the intestine, developed secondary to vasculitis associated with C2 deficiency.  相似文献   
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Journal of Gastroenterology - Following liver transplantation (LT), allograft liver failure can be developed by various causes and requires re-LT. Hence, this study aimed to clarify the...  相似文献   
59.
The cell-cycle status of hematopoietic stem and progenitor cells (HSPCs) becomes activated following chemotherapy-induced stress, promoting bone marrow (BM) regeneration; however, the underlying molecular mechanism remains elusive. Here we show that BM-resident group 2 innate lymphoid cells (ILC2s) support the recovery of HSPCs from 5-fluorouracil (5-FU)–induced stress by secreting granulocyte-macrophage colony-stimulating factor (GM-CSF). Mechanistically, IL-33 released from chemo-sensitive B cell progenitors activates MyD88-mediated secretion of GM-CSF in ILC2, suggesting the existence of a B cell–ILC2 axis for maintaining hematopoietic homeostasis. GM-CSF knockout mice treated with 5-FU showed severe loss of myeloid lineage cells, causing lethality, which was rescued by transferring BM ILC2s from wild-type mice. Further, the adoptive transfer of ILC2s to 5-FU–treated mice accelerates hematopoietic recovery, while the reduction of ILC2s results in the opposite effect. Thus, ILC2s may function by “sensing” the damaged BM spaces and subsequently support hematopoietic recovery under stress conditions.  相似文献   
60.
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