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Metformin, a drug for type 2 diabetes mellitus, has shown therapeutic effects for various cancers. However, it had no beneficial effects on the survival rate of human malignant mesothelioma (HMM) patients. The present study was performed to elucidate the underlying mechanism of metformin resistance in HMM cells. Glucose‐starved HMM cells had enhanced resistance to metformin, demonstrated by decreased apoptosis and autophagy and increased cell survival. These cells showed abnormalities in mitochondria, such as decreased ATP synthesis, morphological elongation, altered mitochondrial permeability transition pore and hyperpolarization of mitochondrial membrane potential (MMP). Intriguingly, Mdr1 was significantly upregulated in mitochondria but not in cell membrane. The upregulated mitochondrial Mdr1 was reversed by treatment with carbonyl cyanide m‐chlorophenyl hydrazone, an MMP depolarization inducer. Furthermore, apoptosis and autophagy were increased in multidrug resistance protein 1 knockout HMM cells cultured under glucose starvation with metformin treatment. The data suggest that mitochondrial Mdr1 plays a critical role in the chemoresistance to metformin in HMM cells, which could be a potential target for improving its therapeutic efficacy.  相似文献   
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In this paper, we introduce a new type of troubled-cell indicator to improve hybrid weighted essentially non-oscillatory (WENO) schemes for solving the hyperbolic conservation laws. The hybrid WENO schemes selectively adopt the high-order linear upwind scheme or the WENO scheme to avoid the local characteristic decompositions and calculations of the nonlinear weights in smooth regions. Therefore, they can reduce computational cost while maintaining non-oscillatory properties in non-smooth regions. Reliable troubled-cell indicators are essential for efficient hybrid WENO methods. Most of troubled-cell indicators require proper parameters to detect discontinuities precisely, but it is very difficult to determine the parameters automatically. We develop a new troubled-cell indicator derived from the mean value theorem that does not require any variable parameters. Additionally, we investigate the characteristics of indicator variable; one of the conserved properties or the entropy is considered as indicator variable. Detailed numerical tests for 1D and 2D Euler equations are conducted to demonstrate the performance of the proposed indicator. The results with the proposed troubled-cell indicator are in good agreement with pure WENO schemes. Also the new indicator has advantages in the computational cost compared with the other indicators.  相似文献   
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ABSTRACT

Purpose

Work-related eye injuries have been reported with a variety of epidemiologic and clinical characteristics. We aimed to identify epidemiologic characteristics of work-related eye injuries and risk factors associated with severe injury in a large metropolitan city.  相似文献   
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Scrub typhus usually presents as acute undifferentiated fever. This cross-sectional study included adult patients presenting with acute undifferentiated fever defined as any febrile illness for ≤ 14 days without evidence of localized infection. Scrub typhus cases were defined by an antibody titer of a ≥ fourfold increase in paired sera, a ≥ 1:160 in a single serum using indirect immunofluorescence assay, or a positive result of the immunochromatographic test. Multiple regression analysis identified predictors associated with scrub typhus to develop a prediction rule. Of 250 cases with known etiology of acute undifferentiated fever, influenza (28.0%), hepatitis A (25.2%), and scrub typhus (16.4%) were major causes. A prediction rule for identifying suspected cases of scrub typhus consisted of age ≥ 65 years (two points), recent fieldwork/outdoor activities (one point), onset of illness during an outbreak period (two points), myalgia (one point), and eschar (two points). The c statistic was 0.977 (95% confidence interval = 0.960–0.994). At a cutoff value ≥ 4, the sensitivity and specificity were 92.7% (79.0–98.1%) and 90.9% (86.0–94.3%), respectively. Scrub typhus, the third leading cause of acute undifferentiated fever in our region, can be identified early using the prediction rule.  相似文献   
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A classic pilomatricoma, which usually presents with an asymptomatic, solitary, firm, subcutaneous nodule in the head, neck, or extremities of the paediatric population, is easily diagnosed based on its characteristic clinical and histopathological features. However, its variants often pose particular diagnostic challenges to clinicians due to their rarity and diverse clinicopathological features. We present a new pseudocystic variant, manifesting as solid lesions floating in a fluid‐filled sac.  相似文献   
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