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Mochizuki and Fukui (Jpn J Ichthyol 30 ( 1983 ) 27–36) studied the development and replacement of the upper jaw teeth in a Japanese fish species, Sicyopterus japonicus (Gobioidei: Sicydiinae), and they reported that worn‐out functional teeth in the upper jaw were not shed outside the skin but were taken into the soft tissue of the upper jaw and completely resorbed there. To date, however, this phenomenon appears poorly documented. Furthermore, the mechanism for the resorption of these teeth remains to be determined. In this study, we examined this phenomenon by using 3D microcomputed tomography (m‐CT), scanning electron microscopy (SEM), and various techniques of light (LM) and electron (EM) microcopy. This study demonstrated that the upper jaw dentition of this fish was more or less simultaneously replaced with the replacement occurring during short time periods and that the lingual movement of the replacement teeth to the functional tooth position advanced simultaneously in a given row. Furthermore, our study also revealed that many worn‐out functional teeth were engulfed by the oral epithelium, invaginated into the lingual shallow ditch of the premaxilla, and were resorbed/degraded completely by numerous foreign body giant cells rather than by odontoclasts during periods of at least three intervals of tooth replacement. The complete resorption/degradation of worn‐out functional teeth in the soft tissue of the upper jaw suggests the possibility of the reuse of their components (minerals such as Ca and P, including Fe) for rapid and successional production of new replacement teeth in the upper jaw of adult S. japonicus. Anat Rec, 2017. © 2017 Wiley Periodicals, Inc. Anat Rec, 301:111–124, 2018. © 2017 Wiley Periodicals, Inc.  相似文献   
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European Radiology - To assess the performance of an advanced “first-reader” workflow for computer-aided detection (CAD) of colorectal adenomas ≥ 6 mm at computed tomographic...  相似文献   
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To minimize the adverse effects of high-dose administration of steroids and cyclophosphamide in patients with myeloperoxidase (MPO) antineutrophil cytoplasmic antibody (ANCA), granulocytapheresis (GCAP) or leukocytapheresis (LCAP) was performed to reduce inflammation. Four patients with rapidly progressive glomerulonephritis (RPGN) and one patient with pulmonary hemorrhage due to MPO-ANCA-associated vasculitis were treated by cytapheresis. The prednisolone (PSL) dose was 0.28 +/- 0.15 mg/kg/day (mean +/- SD) (range 0.18-0.50 g/kg/day). In the 4 RPGN patients, the peak serum creatinine level was 3.7 +/- 1.9 mg/dl (range 1.7 to 5.6 mg/dl). GCAP was performed in 3 RPGN patients and in 1 pulmonary hemorrhage patient. LCAP was performed in 1 RPGN patient. In the 4 RPGN patients, renal function improved after combined therapy with cytapheresis and corticosteroids. In the pulmonary hemorrhage patient, evidence of pulmonary hemorrhage on chest computed tomography scanning diminished after combined therapy with cytapheresis and corticosteroids. Cytapheresis, when combined with a low-dose or intermediate-dose PSL regimen, is effective in the treatment of ANCA-associated vasculitis.  相似文献   
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Quercetin is a promising food component, which can prevent lifestyle related diseases. To understand the dietary intake of quercetin in the subjects of a population-based cohort study and in the Japanese population, we first determined the quercetin content in foods available in the market during June and July in or near a town in Hokkaido, Japan. Red leaf lettuce, asparagus, and onions contained high amounts of quercetin derivatives. We then estimated the daily quercetin intake by 570 residents aged 20–92 years old in the town using a food frequency questionnaire (FFQ). The average and median quercetin intakes were 16.2 and 15.5 mg day−1, respectively. The quercetin intakes by men were lower than those by women; the quercetin intakes showed a low correlation with age in both men and women. The estimated quercetin intake was similar during summer and winter. Quercetin was mainly ingested from onions and green tea, both in summer and in winter. Vegetables, such as asparagus, green pepper, tomatoes, and red leaf lettuce, were good sources of quercetin in summer. Our results will help to elucidate the association between quercetin intake and risks of lifestyle-related diseases by further prospective cohort study and establish healthy dietary requirements with the consumption of more physiologically useful components from foods.  相似文献   
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Previous studies have demonstrated that transplantation of neural stem/progenitor cells (NS/PCs) into the lesioned spinal cord can promote functional recovery following incomplete spinal cord injury (SCI) in animal models. However, this strategy is insufficient following complete SCI because of the gap at the lesion epicenter. To obtain functional recovery in a mouse model of complete SCI, this study uses a novel collagen‐based microfiber as a scaffold for engrafted NS/PCs. We hypothesized that the NS/PC–microfiber combination would facilitate lesion closure as well as transplant survival in the transected spinal cord. NS/PCs were seeded inside the novel microfibers, where they maintained their capacity to differentiate and proliferate. After transplantation, the stumps of the transected spinal cord were successfully bridged by the NS/PC‐laden microfibers. Moreover, the transplanted cells migrated into the host spinal cord and differentiated into three neural lineages (astrocytes, neurons, and oligodendrocytes). However, the NS/PC‐laden scaffold could not achieve a neural connection between the rostral end of the injury and the intact caudal area of the spinal cord, nor could it achieve recovery of motor function. To obtain optimal functional recovery, a microfiber design with a modified composition may be useful. Furthermore, combinatorial therapy with rehabilitation and/or medications should also be considered for practical success of biomaterial/cell transplantation‐based approaches to regenerative medicine. © 2015 Wiley Periodicals, Inc.  相似文献   
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